mTOR Activation by PI3K/Akt and ERK Signaling in Short ELF-EMF Exposed Human Keratinocytes

Several reports suggest that ELF-EMF exposures interact with biological processes including promotion of cell proliferation. However, the molecular mechanisms by which ELF-EMF controls cell growth are not completely understood. The present study aimed to investigate the effect of ELF-EMF on keratinocytes proliferation and molecular mechanisms involved. Effect of ELF-EMF (50 Hz, 1 mT) on HaCaT cell cycle and cells growth and viability was monitored by FACS analysis and BrdU assay. Gene expression profile by microarray and qRT-PCR validation was performed in HaCaT cells exposed or not to ELF-EMF. mTOR, Akt and MAPKs expressions were evaluated by Western blot analysis. In HaCaT cells, short ELF-EMF exposure modulates distinct patterns of gene expression involved in cell proliferation and in the cell cycle. mTOR activation resulted the main molecular target of ELF-EMF on HaCaT cells. Our data showed the increase of the canonical pathway of mTOR regulation (PI3K/Akt) and activation of ERK signaling pathways. Our results indicate that ELF-EMF selectively modulated the expression of multiple genes related to pivotal biological processes and functions that play a key role in physio-pathological mechanisms such as wound healing.     

Notes on Scleroderma,Puff balls and Geastrum of Azad Jammu and Kashmir,Pakistan

Six species of mushrooms allied to the Family Sclerodermataceae, Lycoperdaceae and Geastraceae have been described for the first time from Azad Jammu and Kashmir. These are Scleroderma aurantium, Calvatia verrucosia sp. nov., Lycoperdon pedicellaton sp. nov. L. sphaericon sp. nov., L. echinulaton sp. nov., and Geastrum heptaplex sp. nov.     

Regulation of calcium-activated nonselective cation channel activity by cyclic nucleotides in the rat insulinoma cell line,CRI-G1

The regulation of a calcium-activated nonselective cation (Ca-NS⁺) channel by analogues of cyclic AMP has been investigated in the rat insulinoma cell line, CRI-G1. The activity of the channel is modulated by cyclic AMP in a complex way. In the majority of patches (83%) tested concentrations of cyclic AMP of 10 μm and above cause an inhibition of channel activity which is immediately reversible on washing. In contrast, lower concentrations of cyclic AMP, between 0.1 and 1.0 μm, produce a transient activation of channel activity in most patches (63%) tested. One group of analogues, including N⁶-monobutyryl cyclic AMP and N⁶, 2′-O-dibutyryl cyclic AMP reduced the activity of the Ca-NS⁺ channel at all concentrations tested and 2′-O-Monobutyryl cyclic AMP produced inhibition in all patches tested except one, at all concentrations. A second group produced dual concentration-dependent effects on Ca-NS⁺, low concentrations stimulating and high concentrations inhibiting channel activity. 6-Chloropurine cyclic AMP and 8-bromo cyclic AMP produced effects similar to those of cyclic AMP itself. In contrast, 8-[4-chlorophenylthio] cyclic AMP also showed a dual action, but with a high level of activation at all concentrations tested up to 1mm. Ca-NS⁺ channel activity was also predominantly activated by low concentrations of S_p-cAMPS. The activating effects of both S_p-cAMPS and cyclic AMP are antagonized by R_p-cAMPS, which by itself only produced a weak inhibition of Ca-NS⁺ channel activity even at concentrations of 10 μm and above. The results are discussed in terms of a model in which cyclic AMP, and other cyclic nucleotides, modulate the activity of the Ca-NS⁺ channel by binding to two separate sites.     

SNP-based markers for discriminating olive (Olea europaea L.) cultivars.

A set of 11 polymorphic markers (1 cleaved amplified polymorphic sequence (CAPS), 2 sequence-characterized amplified regions (SCARs), and 8 single-nucleotide polymorphism (SNP)-derived markers) was obtained for olive cultivar identification by comparing DNA sequences from different accessions. Marker development was more efficient, using sequences from the database rather than cloning arbitrary DNA fragments. Analyses of the sequences of 3 genes from 11 diverse cultivars revealed an SNP frequency of 1 per 190 base pairs in exons and 1 per 149 base pairs in introns. Most mutations were silent or had little perceptible effect on the polypeptide encoded. The higher incidence of transversions (55%) suggests that methylation is not the major driving force for DNA base changes. Evidence of linkage disequilibrium in 2 pairs of markers has been detected. The set of predominantly SNP-based markers was used to genotype 65 olive samples obtained from Europe and Australia, and was able clearly to discriminate 77% of the cultivars. Samples, putatively of the same cultivar but derived from different sources, were revealed as identical, demonstrating the utility of these markers as tools for resolving nomenclature issues. Genotyping data were used for constructing a dendrogram by UPGMA cluster analysis using the simple matching similarity coefficient. Relationships between cultivars are discussed in relation to the route of olive's spread.     

Analysis of a genome-wide association study-linked locus (CCR6) in Asian rheumatoid arthritis

A genome-wide association study in Japan identified the C-C chemokine receptor type 6 gene (CCR6) as associated with rheumatoid arthritis (RA). This finding has not been validated in other Asian populations. A case-control study involving 996 subjects, comprising 440 controls and 556 RA patients, was done to determine their anticyclic citrullinated peptide (anti-CCP) antibody status and CCR6 polymorphism (rs3093024) genotype. Three hundred eighty-seven patients were anti-CCP positive and 153 anti-CCP negative. Logistic regression showed that allele A was likely to increase the risk of developing RA among females via a recessive model (odds ratio [OR]=1.55, 95% confidence interval [CI]=1.01, 2.39), whereas the risk effect appeared to be reduced among males via an additive model (OR=0.60, 95% CI=0.42, 0.85). Considering only subjects who are anti-CCP positive, allele A increased RA risk among females via a recessive model (OR=1.68, 95% CI=1.07, 2.64) but decreased the risk among males via an additive model (OR=0.59, 95% CI=0.39, 0.89). We showed that CCR6 polymorphism was a risk factor among females but a protective factor among males. Functional studies are warranted to unravel the pathophysiological relevance of the gene variant and other linked variants with RA.     

Astronomical calibration of the Paleocene time

The first complete cyclic sedimentary successions for the early Paleogene from drilling multiple holes have been retrieved during two ODP expeditions: Leg 198 (Shatsky Rise, NW Pacific Ocean) and Leg 208 (Walvis Ridge, SE Atlantic Ocean). These new records allow us to construct a comprehensive astronomically calibrated stratigraphic framework with an unprecedented accuracy for both the Atlantic and the Pacific Oceans covering the entire Paleocene epoch based on the identification of the stable long-eccentricity cycle (405-kyr). High resolution X-ray fluorescence (XRF) core scanner and non-destructive core logging data from Sites 1209 through 1211 (Leg 198) and Sites 1262, 1267 (Leg 208) are the basis for such a robust chronostratigraphy. Former investigated marine (ODP Sites 1001 and 1051) and land-based (e.g., Zumaia) sections have been integrated as well. The high-fidelity chronology is the prerequisite for deciphering mechanisms in relation to prominent transient climatic events as well as completely new insights into Greenhouse climate variability in the early Paleogene. We demonstrate that the Paleocene epoch covers 24 long eccentricity cycles. We also show that no definite absolute age datums for the K/Pg boundary or the Paleocene–Eocene Thermal Maximum (PETM) can be provided by now, because of still existing uncertainties in orbital solutions and radiometric dating. However, we provide two options for tuning of the Paleocene which are only offset by 405-kyr. Our orbitally calibrated integrated Leg 208 magnetostratigraphy is used to revise the Geomagnetic Polarity Time Scale (GPTS) for Chron C29 to C25. We established a high-resolution calcareous nannofossil biostratigraphy for the South Atlantic which allows a much more detailed relative scaling of stages with biozones. The re-evaluation of the South Atlantic spreading rate model features higher frequent oscillations in spreading rates for magnetochron C28r, C27n, and C26n.     

End-of-life modelling in life cycle assessment—material or product-centred perspective?

Purpose

End-of-life (EoL) modelling in life cycle assessment has already been broadly discussed within several studies. However, no consensus has been achieved on how to model recycling in LCA, even though several approaches have been developed. Within this paper, results arising from the application of two new EoL formulas, the product environmental footprint (PEF) and the multi-recycling-approach (MRA) ones, are compared and discussed. Both formulas consider multiple EoL scenarios such as recycling, incineration and landfill.

Methods

The PEF formula has been developed within the PEF programme whose intent is to define a harmonized methodology to evaluate the environmental performance of products. The formula is based on a 50:50 allocation approach, as burdens and benefits associated with recycling are accounted for a 50% rate. The MRA formula has been developed to change focus from products to materials. Recycling cycles and material losses over time are considered with reference to material pools. Allocation between systems is no longer needed, as the actual number of potential life cycles for a certain material is included in the calculation. Both the approaches have been tested within two case studies.

Results and discussion

Methodological differences could thereof be determined, as well as applicability concerns, due to the type of data required for each formula. As far as the environmental performance is concerned, impacts delivered by MRA are lower than those delivered by PEF for aluminium, while the opposite happens for plastic and rubber due to the higher share of energy recovery accounted in PEF formula. Stainless steel impacts are almost the same.

Conclusions and recommendations

The application of the two formulas provides some inputs for the EoL dilemma in LCA. The use of a wider perspective, better reflecting material properties all over the material life cycle, is of substantial importance to properly represent recycling situations. In MRA, such properties are treated and less data are required compared to the PEF formula. On the contrary, the PEF model better accommodates the modelling of products whose materials, at end of life, can undertake the route of recycling or recovery (or landfill), depending on country-specific EoL management practices. However, its application requires more data.

     

Patterns of cell division and expansion in developing petals of Petunia hybrida

The definition of the patterns of cell division and expansion in plant development is of fundamental importance in understanding the mechanics of morphogenesis. By studying cell division and expansion patterns, we have assembled a developmental map of Petunia hybrida petals. Cycling cells were labelled with in situ markers of the cell cycle, whereas cell expansion was followed by assessing cell size in representative regions of developing petals. The outlined cell division and expansion patterns were related to organ asymmetry. Initially, cell divisions are uniformly distributed throughout the petal and decline gradually, starting from the basal part, to form a striking gradient of acropetal polarity. Cell areas, in contrast, increased first in the basal portion and then gradually towards the petal tip. This growth strategy highlighted a cell size control model based on cell-cycle departure time. The dorso-ventral asymmetry can be explained in terms of differential regulation of cell expansion. Cells of the abaxial epidermis enlarged earlier to a higher final extent than those of the adaxial epidermis. Epidermal appendage differentiation contributed to the remaining asymmetry. On the whole our study provides a sound basis for mutant analyses and to investigate the impact of specific (environmental) factors on petal growth.