Genetics and epigenetics of Pinus nigra populations with differential exposure to air pollution

Forest species in the course of their evolution have experienced several environmental challenges, which since historic times include anthropogenic pollution. The effects of pollution on the genetic and epigenetic diversity in black pine (Pinus nigra) forests were investigated in the Amyntaio - Ptolemais - Kozani Basin, which has been for decades the largest lignite mining and burning center of Greece, with a total installed generating capacity of about 4.5 GW, operating for more than 70 years and resulting in large amounts of primary air pollutant emissions, mainly SO₂, NOx and PM10. P. nigra, a biomarker for air pollution and a keystone species of affected natural ecosystems, was examined in terms of phenology (cone and seed parameters), genetics (283 AFLP loci) and epigenetics (606 MSAP epiloci), using two populations (exposed to pollution and control) of the current (mature trees) and future (embryos) stand. It was found that cone, seed, as well as genetic diversity parameters, did not show statistically significant differences between the exposed population and the control. Nevertheless, statistically significant differences were detected at the population epigenetic level. Moreover, there was a further differentiation regarding the intergenerational comparison: while the epigenetic diversity does not substantially change in the two generations assessed in the control population, epigenetic diversity is significantly higher in the embryo population compared to the parental stand in the exposed population. This study sheds a light to genome dynamics in a forest tree population exposed to long term atmospheric pollution burden and stresses the importance of assessing both genetics and epigenetics in biomonitoring applications.

Ecophysiological responses of some maquis (Ceratonia siliqua L., Olea oleaster Hoffm. & Link, Pistacia lentiscus and Quercus coccifera L.) plant species to drought in the east Mediterranean ecosystem

The objective was to examine the adaptation strategies of four maquis species to drought prone environments; typical of the east Mediterranean area in degraded and healthy sites in Turkey. A comparison made between sites for Pistacia lentiscus and Quercus coccifera shows higher net daily photosynthesis in the degraded site, when compared with the healthy site; but Ceratonia siliqua and Olea oleaster exhibited no difference in their photosynthetic activity in environmentally contrasting conditions. The pattern of daily transpiration shows higher values in the degraded site in the case of P. lentiscus and Q. coccifera, while no site effect was observed for C. siliqua and O. oleaster. In the case of Q. coccifera, a behavior similar to C. siliqua was observed. A comparison made between C. siliqua and O. oleaster to observe seasonal differences in daily patterns of net photosynthesis and transpiration reveals that Q. coccifera had the highest water use efficiency (slope= 2.88; r2 = 0.61), followed by C. siliqua (slope = 2.74; r2 = 0.7), P. lentiscus (slope = 2.56; r2 = 0.52) and O. oleaster (slope = 2.40; r2 = 0.78). Olea oleaster and P. lentiscus performed as a drought tolerant species, being more resistant to aridity and thus indicative of the degradation state of the site. Ceratonia siliqua and Q. coccifera were found avoiding drought by adopting first a water-spending strategy, and then a water-saving strategy.

Dermatofibrosarcoma protuberans occuring in a child

Dermatofibrosarcoma protuberans (DFSP) usually occurs in adults, however it can also occur in infancy and childhood. Diagnosis of DFSP in children is quite difficult given the rarity of the tumor and its variegated appearance. The behavior of this neoplasm is of borderline or intermediate malignancy with a high rate of recurrence but limited metastatic potential. We present the case of an eleven-year old boy who presented with a slightly raised, not tender lesion on his right shoulder. It had appeared two years before as a red-brown plaque and since then it had gradually grown to a nodule. An excisional biopsy was performed, and the diagnosis of DFSP was made based on the histological and immunohistochemical findings.

Separation of plant membrane lipids by multiple solid-phase extraction

Plant membrane lipids were separated by multiple solid-phase extraction (SPE) in a single run. Elution was performed continuously through the modulated stationary phase employing only non-aqueous solvent systems. At the different stages of the glycerolipid separation the SPE manifold combined arninopropyl, arninopropyl/silica gel and silica gel/aminopropyl weak anion exchanger columns. The glycerolipid extract of pigment-containing plant tissues was cleared from the pigments onto the aminopropyl column. The aminopropyl column with the glycerolipid extract was then connected to a silica gel column from which monogalactosyldiacylglycerol, phosphatidylethanolamine, phosphatidylglycerol and digalactosyldiacylglycerol were eluted as individual fractions. The elution was performed under polarity, pH and temperature gradient conditions. To continue the separation, the aminopropyl column was discarded and the silica gel column containing the remaining glycerolipid extract was connected to an aminopropyl anion exchanger column. Individual fractions of sulfoquinovosyldiacylglycerol, phosphatidylcholine and phosphatidylinositol were now eluted. The separation process was supported by ammonium counter ions and by the polarity gradient of the elution systems used. The membrane lipids were isolated from pigment-containing (rice and maize leaves and rice leafy stems) and pigment-free (rice roots) tissues. The repeatability for a standard glycerolipid mixture was 2-6% (n=7), and for rice leaf lipid extracts, 3-7% (n=5). Glycerolipid recovery was 87-95%.

Determination of glycerolipid composition of rice and maize tissues using solid-phase extraction

Currently available techniques for the separation and characterization of different glycerolipids are complicated and/or time consuming. By modulating the stationary phase in a solid-phase extraction (SPE) manifold, efficient and rapid separation of plant membrane lipids was achieved. The glycerolipids from rice and maize tissues were separated into seven classes (monogalactosyldiacylglycerol, digalactosyldiacylglycerol, phosphatidylethanolamine, phosphatidylcholine, sulphoquinovosyldiacylglycerol, phosphatidylinositol and phosphatidylglycerol). The pigments present in the rice and maize leaves and rice stems were successfully removed from the total lipid extracts. Pigment-free plant tissue (rice roots) was also analysed. The fatty acid profile of each lipid class isolated by SPE agreed well with those obtained by other separation techniques. The recovery of glycerolipids was at least 87%.