Organochlorine pesticides in Muraena helena L. 1758 from the Eastern Adriatic Sea

This work examines the bioaccumulated organochlorine compounds in Muraena helena to draw attention to this species as a potential bioindicator organism. The morays were caught in the East Adriatic Sea, Elaphite Islands, near Dubrovnik, Croatia (lat: 42°45′38.8″; long: 17°45′53.6″) at the same location in summer (August, 2009) and winter (January, 2010), at depths from 5 to 10 m. Nine fish were caught by longline hooks per each field trip (total in summer and winter, N = 18). No single fish was free of organochlorines (OC), but not all pesticides were present in every fish. The concentration level was: Endrin > ppDDE > Heptachlor epoxide > Heptachlor > Aldrine > Lindane > βHCH > δHCH > Endrin aldehyde). Endrin was the only pesticide approaching the maximum concentrations proposed by the European Union and Croatia (summer max. concentration = 14.75 μg kg^?1; winter max. concentration = 8.35 μg kg^?1). All other pesticides ranged from 0.1 to 0.7 μg kg^?1. Heptachlor was absent in winter and δ‐HCH and Endrin aldehyde in summer, while Lindane and pp‐DDE had higher (P ≤ 0.05) concentrations in summer. Other residues had similar seasonal concentration levels. The p‐DDT was similar as in other biota from the Adriatic or Mediterranean. HCH concentrations corresponded to those found in organisms from the Italian area of the Adriatic. The endocrine and reproductive disrupting potential of the detected OCs are bases for future studies. Results show that morays are a good bioindicator model, with slight interspecies and seasonal variability in OC bioaccumulation as a consequence of diverse food consumption.     

Different susceptibility of prefrontal cortex and hippocampus to oxidative stress following chronic social isolation stress

Chronic oxidative stress plays an important role in depression. The aim of present study was to examine the stress-induced changes in serum corticosterone (CORT) levels, cytosolic protein carbonyl groups, malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO) and total superoxide dismutase (SOD) activity in the prefrontal cortex versus hippocampus of male Wistar rats exposed to acute (2 h of immobilization or cold), chronic (21d of social isolation) stress, and their combination (chronic + acute stress). The subcellular distribution of nuclear factor-κB (NF-κB) and cytosolic cyclooxygenase 2 (COX-2) protein expressions were also examined. Depressive- and anxiety-like behaviors were assessed via the forced swim, sucrose preference, and marble burying tests in chronically isolated rats. Although both acute stressors resulted in elevated CORT, increased MDA in the prefrontal cortex and NF-κB activation accompanied by increased NO in the hippocampus were detected only following acute cold stress. Chronic isolation resulted in no change in CORT levels, but disabled appropriate response to novel acute stress and led to depressive- and anxiety-like behaviors. Increased oxidative/nitrosative stress markers, likely by NF-κB nuclear translocation and concomitant COX-2 upregulation, associated with decreased SOD activity and GSH levels, suggested the existence of oxidative stress in the prefrontal cortex. In contrast, hippocampus was less susceptible to oxidative damage showing only increase in protein carbonyl groups and depleted GSH. Taken together, the prefrontal cortex seems to be more sensitive to oxidative stress than the hippocampus following chronic isolation stress, which may be relevant for further research related to stress-induced depressive-like behavior.     

Uranium distribution in broiler organs and possibilities for protection

The aim of the present study was to investigate the distribution of uranium (uranyl nitrate hexahydrate, UN) in muscle and organs (kidney, liver, and brain) of broilers, after a 7-day contamination with UN and administration of two different adsorbents (organobentonite and organozeolite). The birds were contaminated during 7 days with 25 mg/UN per day. Adsorbents were given via gastric tube, immediately after contamination with UN. In group 1 that did not receive any adsorbents, histopathological changes in the contaminated broilers were observed in small intestine, liver, and kidney in the form of necrosis of intestinal villi, oedema and cytoplasmic vacuolation of hepatocytes, and dystrophic changes in the kidney tubules epithelium. Organobentonite administered via gastric tube (group 2) reduced uranium distribution by 66 % in kidney, 81 % in liver, and 34 % in brain. In group 3, administration of organozeolite reduced uranium distribution by 67 % in kidney, 68 % in liver, and 49 % in brain. In groups 2 and 3, where the broilers received adsorbents immediately after the UN contamination, no histopathological lesions were observed.     

Diarylheptanoids from Green Alder Bark and Their Potential for DNA Protection

Nine diarylheptanoids, 1 – 9 , catechin ( 11 ), and a phenolic glucoside, 10 , were isolated from the bark of green alder (Alnus viridis). Four of the isolated compounds, i.e., 2, 5, 8, 10 , are new. The structures of 1 – 11 were determined on the basis of spectroscopic data. All isolated compounds were evaluated for their in vitro protective effects on chromosome aberrations in peripheral human lymphocytes using cytokinesis‐block micronucleus (CBMN) assay. Almost all of them exerted a pronounced effect of decreasing DNA damage of human lymphocytes, acting stronger than the known synthetic protector amifostine.     

Leaf n‐Alkanes as Characters Differentiating Coastal and Continental Juniperus deltoides Populations from the Balkan Peninsula

The composition of the cuticular n‐alkanes isolated from the leaves of nine populations of Juniperus deltoides R.P.Adams from continental and coastal areas of the Balkan Peninsula was characterized by GC‐FID and GC/MS analyses. In the leaf waxes, 14 n‐alkane homologues with chain‐lengths ranging from C₂₂ to C₃₅ were identified. n‐Tritriacontane (C₃₃) was dominant in the waxes of all populations, but variations between the populations in the contents of all n‐alkanes were observed. Several statistical methods (ANOVA, principal component, discriminant, and cluster analyses) were used to investigate the diversity and variability of the cuticular‐leaf‐n‐alkane patterns of the nine J. deltoides populations. This is the first report on the n‐alkane composition for this species. The multivariate statistical analyses evidenced a high correlation of the leaf‐n‐alkane pattern with the geographical distribution of the investigated samples, differentiating the coastal from the continental populations of this taxon.     

Composition, antimicrobial and antioxidant activity of the extracts of Eryngium palmatum Pančić and Vis. (Apiaceae)

The chemical composition, antimicrobial and antioxidant activity of Eryngium palmatum, an endemic plant species from the Balkan Peninsula, were investigated. The flavonoids apigenin (9.5±0.3 mg g^?1) and apigenin 7-O-glucoside (2.4±0.1 mg g^?1) were determined in a methanol extract of aerial parts using HPLC analysis. The methanol extract of roots contained catechin (5.0±0.1 mg g^?1), epicatechin (2.9±0.1 mg g^?1), chlorogenic acid (1.6±0.0 mg g^?1), gallic acid (0.9±0.0 mg g^?1) and rosmarinic acid (0.9±0.2 mg g^?1). GC-FID and GCMS analysis of a chloroform extract of aerial parts showed that the main volatile constituents were falcarinol, linoleic acid, hexadecanoic acid and methyl linoleate (comprising 32.6%; 24.4%; 19.9; 13.2% of the volatile fraction, respectively), while octanoic acid, tetradecanol and dodecanol dominated in the chloroform extract of the roots (34.9%; 25.8%; 22.2% of the volatile fraction, respectively). Investigation of antimicrobial activity by broth microdilution showed that the methanol and chloroform extracts of aerial parts and roots exerted a significant effect (MIC 3.5–15.6 μg mL^?1) against tested Gram-positive and Gram-negative bacteria. The methanol extracts of aerial parts or roots exerted moderate ferric reducing antioxidant power, DPPH radical scavenging activity and hydroxyl radical scavenging activity.     

Genetic variation and relationship of alfalfa populations and their progenies based on RAPD markers

The aim of investigation was to evaluate genetic variation and relationship among alfalfa populations and their offspring, with minimal cost, by using DNA marker analysis. RAPD analysis was performed on bulked DNA samples of five alfalfa parental populations and their progenies: 20 F1 populations from reciprocal diallel crosses and five S1 populations from self-pollination. Twenty primers generated 217 bands, ranging in size from 300 to 6000 bp, with the average number of bands per primer of 10.85 and polymorphism information content of 0.246. Percentage of polymorphic loci, effective number of alleles, expected heterozygosity and Shannon’s information index were used to estimate genetic variation. Higher diversity was observed in F1 progeny populations, while genetic variation in parental populations and S1 progenies remained similar. The genetic relatedness of alfalfa populations was analysed by UPGMA and Bayesian model-based clustering approach. In both types of analysis selfpollinated progenies were grouped. Furthermore, the hybrid offspring where Zuzana, and RSI 20 were maternal parents were placed in separate groups. The results indicate that use of RAPD markers on bulked DNA samples can be fast and cost-effective way for differentiation of alfalfa parental populations and their offspring, as well as for evaluation of their genetic relationships.     

Methylation-specific PCR: four steps in primer design

Methylation-specific PCR (MSP) is still the method of choice for a single gene methylation study. The proper design of the primer pairs is a prerequisite for obtaining reliable PCR results. Despite numerous protocols describing the rules for MSP primer design, none of them provide a comprehensive approach to the problem. Our aim was to depict a workflow for the primer design that is concise and easy to follow. In order to achieve this goal, adequate tools for promoter sequence retrieval, MSP primer design and subsequent in silico analysis are presented and discussed. Furthermore, a few instructive examples regarding a good versus a poor primer design are provided. Finally, primer design is demonstrated according to the proposed workflow. This article aims to provide researchers, interested in a single gene methylation studies, with useful information regarding successful primer design.