Multiple biomarkers of pollution effects in caged mussels on the Greek coastline.

A suite of biomarkers was measured in caged mussels at areas impacted by different anthropogenic activities along the Greek coastline to assess biological effects of environmental pollution. Mussels were caged at coastal sites in the vicinity of major cities, in areas influenced by major industries, agricultural practices and in islands away from known sources of pollution. Biomarkers indicative of neurotoxicity (acetylcholinesterase, AchE), oxidative stress (catalase, CAT), phase II biotransformation of xenobiotics (glutathione S-transferase, GST), metal exposure (metallothioneins, MTs) and protein synthesis (RNA:DNA ratio) were measured to assess effects of various types of pollutants. AchE activity proved to be the most responsive biomarker with decreased values at sites influenced by agricultural, urban and industrial activities. Decreased CAT and GST activities and increased MTs levels were recorded at a number of anthropogenic-impacted sites. RNA:DNA ratio showed a biphasic response as both high and low values were found at impacted sites. Principal component analysis clearly distinguished sites receiving pollution inputs from non-polluted sites. The combination of the selected biomarkers used in caged mussels resulted useful in the assessment of the effects of environmental pollution.

Ex vivo study of the efficacy of H-files and rotary Ni-Ti instruments to remove gutta-percha and four types of sealer.

AIM: To compare the efficacy of ProFile rotary Nickel-Titanium (Ni-Ti) instruments and Hedstroem-files (H-files) combined with Gates-Glidden (GG) drills during removal of gutta-percha root fillings used in combination with one of the four representative sealers. METHODOLOGY: Forty-eight single-rooted human teeth, with fully formed apices and straight root canals were used. The root canals were accessed and instrumented using a stepback technique with H-files. They were randomly assigned to four groups and subsequently filled with a combination of lateral and vertical condensation of gutta-percha and one of the following sealers: Roth 811, AH26, Endion and Roekoseal. The root fillings were removed 1 year later, using either H-files in combination with GG drills or the ProFile Ni-Ti system. Teeth were then grooved longitudinally and split. The amount of gutta-percha and sealer remaining on the root canal walls was traced and scored visually with the aid of a stereomicroscope. The scores were analysed and statistically compared with the Kruskal-Wallis test between the ProFile and H-file groups, as well as among the four sealer subgroups. Two samples from each group were studied under the scanning electron microscope to enhance inspection of canal walls and remaining material. RESULTS: Sealer remnants were observed with both techniques mainly in the middle and apical third of the root canal. The ProFile system and the H-files were associated with similar amounts of remaining filling material (P > 0.05). In the cervical third of the root canal all sealer remnants were removed with both techniques. In the middle and apical third AH26 was associated with a statistically significant greater quantity of remnants on the root canal walls with both removal techniques (P < 0.05). Endion, Roth 811 and Roekoseal were associated with approximately the same amount of filling material in the middle third of the root canal (P > 0.05), whereas in the apical third Endion was associated with significantly more remnants of filling material than the other two sealers with either ProFile or H-files (P < 0.05). CONCLUSIONS: None of the methods used for the removal of root fillings was totally effective, especially in the apical third of the root canal.

Isolation and characterization of a protein from Mendole (Spicara maena) eggs that binds to DNA and inhibits its replication as well as its acid precipitation.

Proteins that bind and protect nucleic acids from acid precipitation have been characterized from human and mouse plasma. In the present study, one protein from Mendole (Spicara maena) eggs was purified to homogeneity, by means of acetone fractionation and Sephadex G-100 gel filtration. The protein inhibited DNA replication, exerted by various DNA polymerases. Amino-acid sequence analysis in the amino terminus revealed a unique sequence. Its possible physiological role is discussed.