Long-term biomonitoring of lichen and bryophyte biodiversity at Burnham Beeches SAC and global environmental change

Long-term monitoring began 20 years ago at Burnham Beeches Site of Special Interest (SSSI), National Nature Reserve (NNR) and European Special Area of Conservation (SAC) lying 40 km west of London as a consequence of the authorization of an application to extract gravel from an adjacent site lying north of Slough Trading Estate. Dust monitoring (sticky pads) and photographic monitoring, recording and image analysis was instigated in 1992 on Parmelion communities to assess changes in lichen growth, health and community composition. Long-term monitoring identifies that the lichen flora on free-standing trees has undergone rapid expansion from a near dominance by the SO₂-tolerant ‘acidophyte’ species Lecanora conizaeoides and Hypogymnia physodes following reductions in SO₂ concentrations. Long-term influences of low levels of eutrophication, gaseous pollutants (particularly globally rising background ozone concentrations) on lichen and bryophyte communities and succession under changing climatic conditions are unknown. Soil–plant relationships, lichen–invertebrate interactions and a pollution legacy must also be considered.     

A potentiated cooperation of carbonic anhydrase IX and histone deacetylase inhibitors against cancer

Abstract

The emergence of tumour recurrence and resistance limits the survival rate for most tumour-bearing patients. Only, combination therapies targeting pathways involved in the induction and in the maintenance of cancer growth and progression might potentially result in an enhanced therapeutic efficacy. Herein, we provided a prospective combination treatment that includes suberoylanilide hydroxamic acid (SAHA), a well-known inhibitor of histone deacetylases (HDACs), and SLC-0111, a novel inhibitor of carbonic anhydrase (CA) IX. We proved that HDAC inhibition with SAHA in combination with SLC-0111 affects cell viability and colony forming capability to greater extent than either treatment alone of breast, colorectal and melanoma cancer cells. At the molecular level, this therapeutic regimen resulted in a synergistically increase of histone H4 and p53 acetylation in all tested cell lines. Overall, our findings showed that SAHA and SLC-0111 can be regarded as very attractive combination providing a potential therapeutic strategy against different cancer models.     

Application of Semipermeable Membrane Devices (SPMDs) and Benthic Mussels to Evaluate the Bioavailability of Sediment-associated DDTs

Bioavailability of dichlorodiphenyltrichloroethanes (DDTs) in surface sediments was evaluated with semipermeable membrane devices (SPMDs) and two different sediment-dwelling benthic mussels, Bellamya aeruginosa (B. aeruginosa) and Corbicula fluminea (C. fluminea). After 28d laboratory exposure, the positive correlations of DDT concentrations between both SPMDs and benthic mussels with sediments documented that the bioavailability of DDTs was mainly affected by surrounding sediments, while the observed differences of DDT concentrations and congener proportions between B. aeruginosa and C. fluminea were due to the specific physiological characteristics of organisms and different physico-chemical properties of contaminants. Comparisons between SPMDs and benthic mussels showed higher values of biota-sediment accumulation factors (BSAF, 0.63-3.61 for B. aeruginosa and 2.19-17.08 for C. fluminea) than device accumulation factors (DAF, 1.00-1.74). This indicated that living organisms bioaccumulated much more DDTs from sediments than SPMDs due to the different exposure and uptake routes. Strong positive associations between DDTs in SPMDs and benthic mussels indicated SPMDs could mimic the bioaccumulation of DDTs, especially in C. fluminea. However, given the distinct differences observed for both concentrations and congener proportions of DDTs in SPMDs and B. aeruginosa, future study should be directed to develop reliable models with various sediment-dwelling organisms before SPMDs are routinely used in field study.     

Biomarker responses and accumulation of hazardous substances in mussels (Mytilus trossulus) transplanted along a pollution gradient close to an oil terminal in the Gulf of Finland (Baltic Sea)

Baltic Sea blue mussels (Mytilus trossulus) were used as sentinel organisms to detect the biological effects of chemical contamination in the low salinity environment. Mussels naturally adapted to a salinity of ca. 6.0 PSU were caged for 30 days at four sites along an assumed pollution gradient (salinity ca. 4.5 PSU) in the vicinity of Finland's largest oil refinery and harbor Kilpilahti in the Gulf of Finland. Tissue concentrations and accumulation rates of especially organic contaminants (PAHs, PCBs and organotins) were clearly elevated at the innermost coastal stations near the harbor area. Biological effects of contaminant exposure on caged mussels were evaluated by measuring a suite of biomarkers including catalase, glutathione S-transferase, superoxide dismutase, glutathione reductase, lipid peroxidation, acetylcholinesterase activity and lysosomal membrane stability. Mussels transplanted near the harbor area were able to elevate their antioxidant defense in response to environmental contamination. Reduced morphometric condition index and soft tissue growth rate together with increased lipid peroxidation and low lysosomal membrane stability were also observed at the most contaminated site. The results suggest that caging of M. trossulus for four weeks at lower salinity is a feasible method for the detection of environmental pollution also in low salinity areas of the Baltic Sea.     

Peroxisomal proteomic approach for protein profiling in blue mussels (Mytilus edulis) exposed to crude oil

Peroxisomal proteomic protein profiles of exposure to marine pollution have been recently introduced in biomonitoring experiments. However, laboratory experiments to study the independent effect of common pollutants are needed to define a minimal protein expression signature (PES) of exposure to a specific pollutant. The aim of this study was to obtain PESs in blue mussels (Mytilus edulis) exposed to two different crude oil mixtures for future application in biomonitoring areas affected by oil spills. In the study, peroxisome-enriched fractions from digestive gland of M. edulis (L., 1758) were analysed by two-dimensional fluorescence difference electrophoresis (DIGE) and mass spectrometry (MS) after 3 weeks of exposure to crude oil mixtures: crude oil or crude oil spiked with alkylated phenols (AP) and extra polycyclic aromatic hydrocarbons (PAH) in a laboratory flow-through system. A minimal PES composed by 13 protein spots and unique PESs of exposure to the two different mixtures were identified. A total of 22 spots from the two-dimensional maps that had shown a significant increase or decrease in abundance in each of the exposed groups exposed were analysed. The hierarchical clustering analysis succeeded in discriminating the exposed groups from the control groups based on the unique PES. The PESs obtained were consistent with protein patterns obtained in previous field experiments. The results suggest that the protein profiles obtained by peroxisomal proteomics could be used to assess oil exposure in marine pollution assessments.     

Nitrogen and carbon contents and δ15N and δ13C signatures in six bryophyte species: assessment of long‐term deposition changes (1980–2010) in Spanish beech forests

In this study we used recent (2010) and herbarium material (1980) of six bryophyte species to assess long‐term atmospheric deposition in natural forested areas in northern Spain. For this purpose, tissue nitrogen and carbon content, as well as δ¹³C and δ¹⁵N signatures of samples of Hypnum cupressiforme, Polytrichastrum formosum, Leucobryum juniperoideum, Rhytidiadelphus loreus, Homalothecium lutescens and Diplophyllum albicans were analysed and comparisons made between years and species. In addition, the usefulness of each of the six species was evaluated. The range of values observed was similar to that in other studies carried out in rural areas. Significantly lower values were found in 2010 for N (H. cupressiforme), δ¹⁵N (R. loreus and D. albicans), C (R. loreus) and δ¹³C (all except L. juniperoideum). Our natural areas are thus now less influenced by atmospheric pollutants than they were, most probably due to changes in some traditional local activities. Differences were observed between species for all the four parameters studied, so different species must not be analysed together. Finally, R. loreus and H. lutescens seem to be good bioindicators, sensitive even with a few samples, although further studies are needed to corroborate their usefulness.     

Responses of serum chemokines to dramatic changes of air pollution levels,a panel study

Abstract

Background: Despite the in vitro and in vivo evidence, studies are limited in evaluating whether chemokines are potential inflammatory mediators in response to air pollution exposure in humans.

Methods: We conducted a panel study coinciding with the Beijing Olympics, when temporary air pollution controls were implemented. We measured a suite of serum chemokines among healthy adults before, during and after the Olympics, respectively. Linear mixed-effect models were used to evaluate changes in chemokine levels over the three time periods.

Results: In response to the 50% drop in air pollution levels during the games, levels of RANTES, MCP-2, and TARC decreased by 25.8%, 20.9% and 35.3%, respectively (p?<?0.001) from pre-Olympics, and then increased by 45.8%, 34.9% and 61.5%, respectively (p?<?0.001) after the games when air pollution levels went up again. Similar patterns were observed in subgroup analyses by sex, age, smoking and body mass index. GRO-α and IL-8 decreased significantly during the games (22.5% and 30.4%), and increased non-significantly after the games. Eotaxin-1 only increased significantly from during- to post-games.

Conclusions: The strongest associations with air pollution levels were observed among RANTES, TARC and MCP-2. Those chemokines may play important roles in the air pollution-induced inflammatory pathway.     

Heavy metal pollution negatively correlates with anuran species richness and distribution in south‐eastern Australia

Heavy metal pollution has likely played an important role in global biodiversity decline, but there remains a paucity of information concerning the effects of metals on amphibian diversity. This study assessed anuran species richness and distribution in relation to sediment metal content and water chemistry in wetlands located along the Merri Creek corridor in Victoria, south‐eastern Australia. Anurans were present in 60% (21/35) of study sites, with a total of six species detected: the eastern common froglet (Crinia signifera), the eastern sign‐bearing froglet (Crinia parinsignifera), the southern brown tree frog (Litoria ewingii), the growling grass frog (Litoria raniformis), the eastern banjo frog (Limnodynastes dumerilii) and the spotted marsh frog (Limnodynastes tasmaniensis). Mean species richness was 1.77 ± 0.32 per site, and species richness ranged from zero to six species per site. Across sites, species richness correlated negatively with sediment concentrations of six heavy metals: copper, nickel, lead, zinc, cadmium and mercury. Species richness also correlated negatively with wetland water electrical conductivity (a proxy for salinity) and concentrations of orthophosphate. Distributions of the three most commonly observed frog species (C. signifera, L. tasmaniensis and L. ewingii) were significantly negatively associated with the total level of metal contamination at individual sites. The study is the first to provide evidence for an association between metal contamination and anuran species richness and distribution in the southern hemisphere, adding to a small but growing body of evidence that heavy metal pollution has contributed to global amphibian decline.     

High prevalence of asthma symptoms in Warao Amerindian children in Venezuela is significantly associated with open-fire cooking: a cross-sectional observational study

Background

The International Study on Asthma and Allergies in Childhood (ISAAC) reported a prevalence of asthma symptoms in 17 centers in nine Latin American countries that was similar to prevalence rates reported in non-tropical countries. It has been proposed that the continuous exposure to infectious diseases in rural populations residing in tropical areas leads to a relatively low prevalence of asthma symptoms. As almost a quarter of Latin American people live in rural tropical areas, the encountered high prevalence of asthma symptoms is remarkable. Wood smoke exposure and environmental tobacco smoke have been identified as possible risk factors for having asthma symptoms.

Methods

We performed a cross-sectional observational study from June 1, 2012 to September 30, 2012 in which we interviewed parents and guardians of Warao Amerindian children from Venezuela. Asthma symptoms were defined according to the ISAAC definition as self-reported wheezing in the last 12 months. The associations between wood smoke exposure and environmental tobacco smoke and the prevalence of asthma symptoms were calculated by means of univariate and multivariable logistic regression analyses.

Results

We included 630 children between two and ten years of age. Asthma symptoms were recorded in 164 of these children (26%). The prevalence of asthma symptoms was associated with the cooking method. Children exposed to the smoke produced by cooking on open wood fires were at higher risk of having asthma symptoms compared to children exposed to cooking with gas (AOR 2.12, 95% CI 1.18 - 3.84). Four percent of the children lived in a household where more than ten cigarettes were smoked per day and they had a higher risk of having asthma symptoms compared to children who were not exposed to cigarette smoke (AOR 2.69, 95% CI 1.11 - 6.48).

Conclusion

Our findings suggest that children living in rural settings in a household where wood is used for cooking or where more than ten cigarettes are smoked daily have a higher risk of having asthma symptoms.