MARS Bulletin Vol. 20, No. 12

MARS BulletinJRC.H.4-Monitoring Agricultural Resource

MARS Bulletin Vol.22 No 1 (2014)

Crop Monitoring in EuropeJRC.H.4-Monitoring Agricultural Resource

MARS Bulletin Vol. 23 No 1 (2015) - Weakly hardened winter cereals in Europe

Crop monitoring in EuropeJRC.H.4-Monitoring Agricultural Resource

MARS Bulletin Vol.22 No 2 (2014) - Exceptional mild winter and very wet in western Europe

Crop Monitoring in EuropeJRC.H.4-Monitoring Agricultural Resource

MARS Bulletin Vol.21 No. 12

MARS Bulletin Vol.21 No. 12JRC.H.4-Monitoring Agricultural Resource

Early heat waves over Italy and their impacts on durum wheat yields

In the last decades the Euro-Mediterranean region has experienced an increase in extreme temperature events such as heat waves. These extreme weather conditions can strongly affect arable crop growth and final yields. Here, early heat waves over Italy from 1995 to 2013 are identified and characterised and their impact on durum wheat yields is investigated. As expected, results confirm the impact of the 2003 heat wave and highlight a high percentage of concurrence of early heat waves and significant negative yield anomalies in 13 out of 39 durum wheat production areas. In south-eastern Italy (the most important area for durum wheat production), the percentage of concurrent events exceeds 80%.JRC.H.4-Monitoring Agricultural Resource

Leptin’s and antigen-presenting cells’ functions in periodontitis – an overview / Leptin e as funções das células que apresentam antigénios na periodontite - uma visão geral

Leptin is a hormone synthesized predominantly by white adipose tissue. Its production levels are directly proportional to the total mass of this tissue in an individual’s body. Apart from its classic role in the regulation of hunger and satiety, it also plays an important part in scenarios involving innate and adaptive immune responses. It has been discovered that leptin levels are altered in a variety of inflammatory responses, such as periodontitis, a condition which derives from a persistent inflammatory immune response from a host facing bacterial infection. The initial trigger for this reaction is the recognition of the pathogens by antigen presenting cells, such as macrophages and dendritic cells, whose actions can be influenced by leptin. This review aims to present the relationship between leptin, dendritic cells and macrophages in the context of periodontal disease. Thus, we have assembled the most important findings related to leptin’s role in the modulation of the immune response carried out by these cells in periodontitis

First Morphological and Molecular Evidence of the Negative Impact of Diatom-Derived Hydroxyacids on the Sea Urchin Paracentrotus lividus.

Oxylipins (including polyunsaturated aldehydes PUAs, hydoxyacids and epoxyalcohols) are the end-products of a lipoxygenase/hydroperoxide lyase metabolic pathway in diatoms. To date very little information is available on oxylipins other than PUAs, even though they represent the most common oxylipins produced by diatoms. Here, we report, for the first time, on the effects of two hydroxyacids, 5-and 15-HEPE, which have never been tested before, using the sea urchin Paracentrotus lividus as a model organism. We show that HEPEs do induce developmental malformations but at concentrations higher when compared to PUAs. Interestingly, HEPEs also induced a marked developmental delay in sea urchin embryos, which has not hitherto been reported for PUAs. Recovery experiments revealed that embryos do not recover following treatment with HEPEs. Finally, we report the expression levels of 35 genes (involved in stress, development, differentiation, skeletogenesis and detoxification processes) to identify the molecular targets affected by HEPEs. We show that the two HEPEs have very few common molecular targets, specifically affecting different classes of genes and at different times of development. In particular, 15-HEPE switched on fewer genes than 5-HEPE, up-regulating mainly stress-related genes at a later pluteus stage of development. 5-HEPE was stronger than 15-HEPE, targeting twenty-four genes, mainly at the earliest stages of embryo development (at the blastula and swimming blastula stages). These findings highlight the differences between HEPEs and PUAs and also have important ecological implications because many diatom species do not produce PUAs but rather these other chemicals derived from the oxidation of fatty acids

MARS Bulletin Vol. 20, No. 11

BulletinJRC.H.4-Monitoring Agricultural Resource

Teratogenic Effects of Diatom Metabolites on Sea Urchin Paracentrotus lividus Embryos

The diatom-derived polyunsaturated aldehydes (PUAs), 2-trans,4-trans-decadienal, 2-trans,4-trans-octadienal, 2-trans,4-trans,7-octatrienal, 2-trans,4-trans-heptadienal, as well as tridecanal were tested on early and later larval development in the sea urchin Paracentrotus lividus. We also tested the effect of some of the more abundant diatom polyunsaturated fatty acids (PUFAs) on development, in particular 5,8,11,14,17-eicosapentaenoic acid (EPA), one of the main precursors of diatom PUAs, as well as 4,7,10,13,16,19-docosahexaenoic acid (DHA), 6,9,12,15-octadecatetraenoic acid (stearidonic acid), 6,9,12-octadecatrienoic acid (γ-linolenic acid) and 9,12-octadecadienoic acid (linoleic acid). PUAs blocked sea urchin cell cleavage in a dose dependent manner and with increasing chain length from C7 to C10 PUAs, with arrest occurring at 27.27 μM with heptadienal, 16.13 μM with octadienal, 11.47 μM with octatrienal and 5.26 μM with decadienal. Of the PUFAs tested, only EPA and stearidonic acid blocked cleavage, but at much higher concentrations compared to PUAs (331 μM for EPA and 181 μM for stearidonic acid). Sub-lethal concentrations of decadienal (1.32–5.26 μM) delayed development of embryos and larvae which showed various degrees of malformations depending on the concentrations tested. Sub-lethal concentrations also increased the proportion of TUNEL-positive cells indicating imminent death in embryos and larvae. Using decadienal as a model PUA, we show that this aldehyde can be detected spectrophotometrically for up to 14 days in f/2 medium