ALBERT

Description: Little is known about the variability of response to heavy metal stress within tree species, although it could be a key for a better understanding of tolerance mechanisms and for breeding. The aim of the present study was to characterize the natural variation of response to cadmium (Cd) in Populus nigra L. in order to understand the mechanisms of Cd tolerance. For that, two P. nigra genotypes, originating from contrasting environments in northern (genotype 58-861) and southern (genotype Poli) Italy, were exposed to Cd stress in hydroponics for 3 weeks. The effect of stress was estimated by measuring biomass production, photosynthetic performance and accumulation and translocation of Cd at the end of the experiment. To better understand the mechanisms of Cd tolerance, the expression of some candidate genes involved in the ascorbate–glutathione cycle ( ascorbate peroxidase, glutathione reductase, glutathione S-transferase ) and in metal sequestration ( metallothioneins ) was analyzed in leaves. Biomass production and photosynthesis were affected by the treatment in both clones but the southern clone was markedly more tolerant to Cd stress than the other. Nevertheless, the Cd content in leaves was not significantly different between the two clones and was quite low compared to other species. The content of thiols and phytochelatins (PCs), associated with the transcription profile of the glutathione S-transferase gene, indicated relevant differences in the use of the PCs pathway under Cd stress, which could explain the different tolerance to Cd. The northern clone accumulated thiols but down-regulated the GST gene, whereas the southern clone accumulated PCs and up-regulated the GST gene, which can be useful to complex and detoxify Cd. These results suggest that the glutathione pathway is involved in the differential Cd tolerance of the two genotypes. The natural germplasm of P. nigra represents a valuable resource for understanding tolerance to Cd and for selection of plant material for phytoremediation.

Description: Iori V, Pietrini F, Bianconi D, Mughini G, Massacci A, Zacchini M ANALYSIS OF BIOMETRIC, PHYSIOLOGICAL, AND BIOCHEMICAL TRAITS TO EVALUATE THE CADMIUM PHYTOREMEDIATION ABILITY OF EUCALYPT PLANTS UNDER HYDROPONICS Abstract : Wastewater reclamation and reuse represent a feasible solution to meet the growing demand for safe water. An environmentally sustainable technology such as phytoremediation is targeted for the reclamation of polluted waters. To this end, the capability of different plant species to tolerate and accumulate pollutants has to be investigated. In this work, eucalypt plants were studied by analysing biometric, physiological, and biochemical parameters related to cadmium (Cd) tolerance and accumulation in two clones (“Velino ex 7” and “Viglio ex 358”) of Eucalyptus camaldulensis Dehnh. × E. globulus subsp. bicostata (Maiden, Blakely & J.Simm.) J.B. Kirkp exposed to 50 μM CdSO4 under hydroponics for three weeks. The results indicated that both eucalypt clones have a valuable tolerance to cadmium, expressed as the tolerance index (Ti). Biometric investigations showed that, regardless of the clone, the metal exposure affected most parameters related to biomass allocation and leaf growth. On the contrary, significant differences were found between the clones with respect to the chlorophyll content and the Chl a to Chl b ratio. These findings were also confirmed from the analysis of chlorophyll fluorescence transient (OJIP) using the JIP test. Cadmium accumulation occurred in both clones and in particular in the roots, with a poor amount of metal reaching the aerial parts, and the Velino clone showed the highest Cd accumulation. The metal uptake ratio and the phytoextraction efficiency highlight a good Cd phytoremoval ability, especially for the Velino clone. The results are discussed taking into account that, in wastewater phytoremediation systems, root biomass can be completely harvested allowing for the removal of the absorbed metal. Finally, the notable tolerance to submersion and the large environmental adaptability of eucalypt suggest that this plant species represents an interesting candidate for the phytoremediation of Cd-polluted wastewaters. Keywords : Heavy Metals, Metal Tolerance, Wastewater, Forest Plants, Chlorophyll Fluorescence, Rhizofiltration iForest 10 (2): 416-421 (2017) - doi: 10.3832/ifor2129-009 http://iforest.sisef.org/contents/?id=ifor2129-009

Description: Patients afflicted with melanoma show lower vitamin D serum levels (VDSL) than the healthy population. This hypothesis agrees with its well-known antiproliferative features. An observational study was carried out to collect VDSL in patients suffering from melanoma. Our aim was to identify a potential connection between low VDSL and the risk to incur melanoma. Furthermore, we studied the association between VDSL at the diagnosis of melanoma and other germane prognostic factors. The population held in regard was composed of 154 patients with a diagnosis of melanoma between 2016 and 2019. These patients were retrospectively collected from our follow-up storage. We compared VDSL to clinical and pathological parameters (age, sex, tumour location, Breslow’s depth, Clark’s level, histological subtype, ulceration, et aliqua). Moreover, we recruited a control group with negative melanoma history. Mean and median of VDSL were significantly lower in the melanoma group. Instead, we found a negative association between melanoma and VDSL 〉 30 ng/L (OR 0.11; p  1 mm) revealed a statistically significant difference (21.1 ± 8.2 ng/L vs 17.8 ± 8.1; p = 0.01). Moreover, VDSL were significantly lower in melanomas with mitotic rate ≥ 1/mm2 (22.1 ± 8.3 ng/L; p