Heavy metal bioaccumulation in honey bee matrix, an indicator to assess the contamination level in terrestrial environments.

The most significant risk factor for organisms living in an environment contaminated by heavy metals is the metal bioavailability. Therefore, an efficient ecotoxicological approach to metal contamination is the measure of bioaccumulation level in target organisms. In this work, we characterized the heavy metal bioaccumulation in honey bees, Apis mellifera ligustica, collected at 35 sites from Umbria (Central Italy). The comparison of our data with selected Italian investigations revealed metal bioaccumulation in honey bee matrix of the same order of magnitude, with Cd showing a higher variability. To generalize the results, we developed a Honeybee Contamination Index (HCI) based on metal bioaccumulation in honey bees. An application of the HCI to the present dataset revealed cases of low (sixteen sites), intermediate (eighteen sites), and high (one site) metal contaminations. The comparison of HCI values from the Umbrian dataset with values calculated for other Italian and European metadata showed that most of the Umbrian sites fell in the portion of low and intermediate contamination conditions. HCI represented a reliable tool that provided a piece of concise information on metal contamination in terrestrial environments. Parallel to this effort, we have determined, the metal concentrations in the airborne particulate matter (PM10) at three regional background-monitoring stations in Umbria. These stations are representative of the average air quality of the areas of the investigated apiaries. A comparative analysis of metal enrichment factors in PM10, and honey bees suggested that the contamination in the bees was related to the PM10 values only to a minor extent. On the other side, a clear enrichment of metals such as Cd, Mn, Zn, and Cu in the honey bees appeared to depend on very local conditions and was probably related to the use of pesticides and fertilizers, and the resuspension of the locally contaminated soils and agriculture residues.

Heavy metals bioaccumulation in selected tissues of red swamp crayfish: An easy tool for monitoring environmental contamination levels.

In this paper we explored the heavy metal bioaccumulation (Cd, Cu, Pb and Zn) in Procambarus clarkii, a crayfish recently suggested as a potential bioindicator for metals pollution in freshwater systems. The present study is focused on crayfishes populations caught in a heavily polluted industrial and in a reference sites (Central Italy), though the results are generalized with a thorough analysis of literature metadata. In agreement with the literature, the hepatopancreas (Hep, detoxification tissues) of the red swamp crayfish showed a higher concentration of heavy metals in comparison to the abdominal muscle (AbM, not detoxification tissues) in the sites under scrutiny. Hep/AbM concentration ratio was dependent on the specific metal investigated and on its sediment contamination level. Specifically we found that Hep/AbM ratio decreases as follows: Cd (11.7)>Cu (5.5)>Pb (3.6)>Zn (1.0) and Pb (4.34)>Cd (3.66)>Zn (1.69)>Cu (0.87) for the industrial and reference sites, respectively. The analysis of our bioaccumulation data as well as of literature metadata allowed to elaborate a specific contamination index (Toxic Contamination Index, TCI), dependent only on the bioaccumulation data of hepatopancreas and abdominal muscle. In the industrial site, TCI expressed values much higher than the unit for Cd and Cu, confirming that these metals were the main contaminants; in contrast for lower levels of heavy metals, as those observed in the reference site for Cu, Zn and Pb, the index provided values below unit. TCI is proposed as a useful and easy tool to assess the toxicity level of contaminated sites by heavy metals in the environmental management.

Diagnostic and prognostic value of circulating microRNAs in patients with acute chest pain.

OBJECTIVES: To address the diagnostic value of circulating microRNAs (miRNAs) in patients presenting with acute chest pain. DESIGN: In a prospective, international, multicentre study, six miRNAs (miR-133a, miR-208b, miR-223, miR-320a, miR-451 and miR-499) were simultaneously measured in a blinded fashion in 1155 unselected patients presenting with acute chest pain to the emergency department. The final diagnosis was adjudicated by two independent cardiologists. The clinical follow-up period was 2 years. RESULTS: Acute myocardial infarction (AMI) was the adjudicated final diagnosis in 224 patients (19%). Levels of miR-208b, miR-499 and miR-320a were significantly higher in patients with AMI compared to those with other final diagnoses. MiR-208b provided the highest diagnostic accuracy for AMI (area under the receiver operating characteristic curve 0.76, 95% confidence interval 0.72-0.80). This diagnostic value was lower than that of the fourth-generation cardiac troponin T (cTnT; 0.84) or the high-sensitivity cTnT (hs-cTnT; 0.94; both P < 0.001 for comparison). None of the six miRNAs provided added diagnostic value when combined with cTnT or hs-cTnT (ns for the comparison of combinations vs. cTnT or hs-cTnT alone). During follow-up, 102 (9%) patients died. Levels of MiR-208b were higher in patients who died within 30 days, but the prognostic accuracy was low to moderate. None of the miRNAs predicted long-term mortality. CONCLUSION: The miRNAs investigated in this study do not seem to provide incremental diagnostic or prognostic value in patients presenting with suspected AMI.

Role of MicroRNAs in Endothelial Progenitor Cells: Implication for Cardiac Repair.

Endothelial progenitor cells (EPC) are mobilized after myocardial infarction (MI) from the bone marrow to injured sites of the heart where they participate in cardiac repair by revascularization of ischemic tissues. Endothelial progenitor cells have been actively studied, but their exact phenotype and regenerative properties are still controversial. Small trials with progenitor cells of different origins showed modest clinical benefits. It is assumed that a better understanding of the biology of EPC will contribute to improve their therapeutic potential. MicroRNAs (miRNAs) are small single-stranded non-coding RNAs that modulate gene expression by interacting post transcriptionally with protein-coding RNAs. MicroRNAs regulate multiple biological processes involved in cardiac development and disease. While many studies addressed the role of miRNAs in cardiac cells, less is known of the effect of miRNAs in EPC. Recent studies showed that miRNAs indeed regulate the biology of EPC. Since novel technologies to enhance or blunt the functions of miRNAs have been recently developed, it is conceivable that miRNAs may become promising new therapeutic tools. This article will review the recent advances in the knowledge of the effects of miRNAs in EPC and will discuss how miRNAs could be manipulated to improve the regenerative capacities of EPC in the diseased heart.

Deformities of chironomid larvae and heavy metal pollution: from laboratory to field studies.

Mouthpart deformities of Chironomus riparius larvae (Diptera) have been investigated to evaluate the toxic effects of contamination by heavy metals in the Genna Stream (Central Italy), situated in an area subjected to intensive swine farms (40000 heads). The livestock farming (fertirrigation) contributes to metal pollution of the Genna Stream with an increase of copper, zinc, cadmium, chromium and nickel in the sediments of the downstream stations. The incidence of mentum deformities was very high at all sampling stations, about 56%. The highest values of deformities were found in the intermediate river reach (St. 3: 65%) and in March (66%), mainly due to an increase in severe deformities. The high incidence of severe deformities (30%) is attributed to the high pollution level by heavy metals in the sediments, in particular to copper and zinc, which showed the highest average value at St. 3 and in March. This field study reflected the relationships between sediment metal concentrations and chironomid mouthpart deformities, previously observed in laboratory tests, and highlighted these deformities as toxicity endpoints. This feature paves the way for their use as an effective tool in freshwater bioassessment monitoring programs to evaluate the toxic effects of metal contamination in freshwater ecosystems.

Regulation of endothelial progenitor cell function by micrornas.

After cardiac injury, endothelial progenitor cells (EPC) are mobilized from the bone marrow and participate in cardiac repair by increasing revascularization of injured tissues. These cells have been studied actively in the past few years, but their exact phenotype and function are still controversial. In clinical trials, injection of progenitor cells has shown modest benefits. A better understanding of the biology of EPC will allow improving their therapeutic potential. MicroRNAs (miRNAs) are tiny single-stranded non-coding RNAs that negatively regulate gene expression post transcriptionally. They are involved in multiple biological pathways regulating cardiac pathophysiology. Modern technologies using miRNA inhibitors and miRNA mimics have been developed and allow modifying the expression and hence the biological effects of miRNAs. The role of miRNAs in cardiac cells has been extensively investigated. Recent studies suggest that miRNAs play significant roles in EPC, and therefore might be used to improve the regenerative capacities of EPC. In this review, we will first provide a brief overview of the role of EPC in cardiovascular disease. Then, we will summarize current knowledge on the role of miRNAs in EPC and we will discuss how miRNAs may be used to enhance the capacity of EPC to repair the injured heart.

Actinosporean stages of Myxozoan parasites of oligochaetes from Nera River basin, Central Italy.

The aim of this study was to check the occurrence of actinosporean stages of Myxozoan parasites of oligochaetes in the Nera River basin (Central Italy). The investigation was conducted near twelve trout farms (rainbow and brown trout) along the Nera River and in the littoral of the Piediluco Lake. Four actinosporean types, belonging to the collective groups aurantiactinomyxon, triactinomyxon, raabeia and echinactinomyxon, were detected in some of the biotopes investigated (Piediluco Lake and Sordo River). Differential diagnosis, carried out on a sub-sample of spores, showed a complete fitting with forms previously described in literature, with the exception of the triactinomyxon type.