Cadmium and arsenic-induced-stress differentially modulates Arabidopsis root architecture, peroxisome distribution, enzymatic activities and their nitric oxide content

In plant cells, cadmium (Cd) and arsenic (As) exert toxicity mainly by inducing oxidative stress through an imbalance between the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), and their detoxification. Nitric oxide (NO) is a RNS acting as signalling molecule coordinating plant development and stress responses, but also as oxidative stress inducer, depending on its cellular concentration. Peroxisomes are versatile organelles involved in plant metabolism and signalling, with a role in cellular redox balance thanks to their antioxidant enzymes, and their RNS (mainly NO) and ROS. This study analysed Cd or As effects on peroxisomes, and NO production and distribution in the root system, including primary root (PR) and lateral roots (LRs). Arabidopsis thaliana wild-type and transgenic plants enabling peroxisomes to be visualized in vivo, through the expression of the 35S-cyan fluorescent protein fused to the peroxisomal targeting signal1 (PTS1) were used. Peroxisomal enzymatic activities including the antioxidant catalase, the H2O2-generating glycolate oxidase, and the hydroxypyruvate reductase, and root system morphology were also evaluated under Cd/As exposure. Results showed that Cd and As differently modulate these activities, however, catalase activity was inhibited by both. Moreover, Arabidopsis root system was altered, with the pollutants differently affecting PR growth, but similarly enhancing LR formation. Only in the PR apex, and not in LR one, Cd more than As caused significant changes in peroxisome distribution, size, and in peroxisomal NO content. By contrast, neither pollutant caused significant changes in peroxisomes size and peroxisomal NO content in the LR apex

Jasmonic acid methyl ester induces xylogenesis and modulates auxin-induced xylary cell identity with NO Involvement

In Arabidopsis basal hypocotyls of dark-grown seedlings, xylary cells may form from the pericycle as an alternative to adventitious roots. Several hormones may induce xylogenesis, as Jasmonic acid (JA), as well as indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) auxins, which also affect xylary identity. Studies with the ethylene (ET)-perception mutant ein3eil1 and the ET-precursor 1-aminocyclopropane-1-carboxylic acid (ACC), also demonstrate ET involvement in IBA-induced ectopic metaxylem. Moreover, nitric oxide (NO), produced after IBA/IAA-treatments, may affect JA signalling and interact positively/negatively with ET. To date, NO-involvement in ET/JA-mediated xylogenesis has never been investigated. To study this, and unravel JA-effects on xylary identity, xylogenesis was investigated in hypocotyls of seedlings treated with JA methyl-ester (JAMe) with/without ACC, IBA, IAA. Wild-type (wt) and ein3eil1 responses to hormonal treatments were compared, and the NO signal was quantified and its role evaluated by using NO-donors/scavengers. Ectopic-protoxylem increased in the wt only after treatment with JAMe(10 μM), whereas in ein3eil1 with any JAMe concentration. NO was detected in cells leading to either xylogenesis or adventitious rooting, and increased after treatment with JAMe(10 μM) combined or not with IBA(10 μM). Xylary identity changed when JAMe was applied with each auxin. Altogether, the results show that xylogenesis is induced by JA and NO positively regulates this process. In addition, NO also negatively interacts with ET-signalling and modulates auxin-induced xylary identity

Nitric oxide alleviates cadmium- but not arsenic-induced damages in rice roots

Nitric oxide (NO) has signalling roles in plant stress responses. Cadmium (Cd) and arsenic (As) soil pollutants alter plant development, mainly the root-system, by increasing NO-content, triggering reactive oxygen species (ROS), and forming peroxynitrite by NO-reaction with the superoxide anion. Interactions of NO with ROS and peroxynitrite seem important for plant tolerance to heavy metal(oid)s, but the mechanisms underlying this process remain unclear. Our goal was to investigate NO-involvement in rice (Oryza sativa L.) root-system after exposure to Cd or As, to highlight possible differences in NO-behaviour between the two pollutants. To the aim, morpho-histological, chemical and epifluorescence analyses were carried out on roots of different origin in the root-system, under exposure to Cd or As, combined or not with sodium nitroprusside (SNP), a NO-donor compound. Results show that increased intracellular NO levels alleviate the root-system alterations induced by Cd, i.e., inhibition of adventitious root elongation and lateral root formation, increment in lignin deposition in the sclerenchyma/endodermis cell-walls, but, even if reducing As-induced endodermis lignification, do not recover the majority of the As-damages, i.e., enhancement of AR-elongation, reduction of LR-formation, anomalous tissue-proliferation. However, NO decreases both Cd and As uptake, without affecting the pollutants translocation-capability from roots to shoots. Moreover, NO reduces the Cd-induced, but not the As-induced, ROS levels by triggering peroxynitrite production. Altogether, results highlight a different behaviour of NO in modulating rice root-system response to the toxicity of the heavy metal Cd and the metalloid As, which depends by the NO-interaction with the specific pollutant

Cadmium and arsenic affect root development in Oryza sativa L. negatively interacting with auxin

Cadmium (Cd) and arsenic (As), non essential, but toxic, elements for animals and plants are frequently present in paddy fields. Oryza sativa L., a staple food for at least the half of world population, easily absorbs As and Cd by the root, and in this organ the pollutants evoke consistent damages, reducing/modifying the root system. Auxins are key hormones in regulating all developmental processes, including root organogenesis. Moreover, plants respond to environmental stresses, such as those caused by Cd and As, by changing levels and distribution of endogenous phytohormones. Even though the effects of Cd and As on the roots have been investigated in some species, it remains necessary to deepen the knowledge about the cross-talk between these toxic elements and auxin during root formation and development, in particular in agronomically important plants, such as rice. Hence, the research goal was to investigate the interactions between Cd and As, alone or combined, and auxin during the development of rice roots. To reach the aim, morphological, histological and histochemical analyses were carried out on seedlings, exposed or not to Cd and/or As, belonging to the wild type and transgenic lines useful for monitoring indole-3-acetic acid (IAA) localization, i.e., OsDR5:GUS, and IAA cellular influx and efflux, i.e., OsAUX1:GUS and OsPIN5b:GUS. Moreover, the transcript levels of the YUCCA2 and ASA2, IAA biosynthetic genes were also monitored in Cd and/or As exposed wild type seedlings. The results highlight that As and Cd affect cyto-histology and morphology of the roots. In particular, they alter the lateral root primordia organization and development with negative consequences on root system architecture. This is due to a disturbance of IAA biosynthesis and transport, as indicated by the altered expression of both ASA2 and YUCCA2 biosynthetic genes, and AUX1 and PIN5b transporter genes

Differential diagnoses and management strategies in patients with schizophrenia and bipolar disorder

Successful treatment of psychiatric disorders, including bipolar disorder and schizophrenia, is complicated and is affected by a broad range of factors associated with the diagnosis, choice of treatment and social factors. In these patients, treatment management must focus on accurate and early diagnosis, to ensure that correct treatment is administered as soon as possible. In both disorders, the treatment of the disease in the acute phase must be maintained long term to provide continuous relief and normal function; the treatment choice in the early stages of the disease may impact on long-term outcomes. In schizophrenia, treatment non-compliance is an important issue, with up to 50% of patients discontinuing treatment for reasons as diverse as efficacy failure, social barriers, and more commonly, adverse events. Treatment non-compliance also remains an issue in bipolar disorder, as tolerability of mood stabilizers, especially lithium, is not always good, and combination treatments are frequent. In order to achieve an optimal outcome in which the patient continues with their medication life-long, treatment should be tailored to each individual, taking into account treatment and family history, and balancing efficacy with tolerability to maximize patient benefit and minimize the risk of discontinuation. These case studies illustrate how treatment should be monitored, tailored and often changed over time to meet these needs

Improving efficiency of electrostatic spray-assisted vapor deposited Cu2ZnSn(S,Se)4 solar cells by modification of Mo/absorber interface

Electrostatic spray-assisted vapor deposition (ESAVD) is a non-vacuum, low cost and eco-friendly method to produce Cu(In,Ga)Se2 and Cu2ZnSn(S,Se)4 (CZTSSe) absorbers for thin film solar cells, and it is a very promising method for industrialization due to it is high deposition speed and close to unity deposition efficiency. In this work, in order to improve the efficiency of ESAVD deposited CZTSSe solar cells, an ultrathin ZnO (circa 10 nm) layer was employed as an intermediate layer between CZTSSe and Mo back contact to avoid the direct contact between Mo and CZTSSe and reduce the decomposition of CZTSSe during annealing process. XRF and EDX were used to characterize the chemical composition of CZTSSe before and after selenization respectively. SEM and Raman results showed the improved absorber morphology and the reduced direct interfacial reaction between CZTSSe and Mo. The improvement of the CZTSSe/Mo interface due to the intermediate layer was also reflected in the quality of the derived photovoltaic devices, leading to an improved efficiency of ESAVDdeposited kesterite solar cells from 3.25% to 4.03%

Caracterización superficial de pigmentos sobre artefactos paleolíticos de la zona de los Montes Albanos (Roma, Italia) por microscopía óptica y espectroscopía raman

Preliminary results of the characterization of red pigmentations on paleolithic artefacts from the southern area of Montes Albanos (Rome, Italy) are presented. The set of materials consists of three decorated rounded pebblestones and a cortical flint blade typologically attributable to the Upper Paleolithic (Final Epigravetense, 14,000-12,000 cal BP). The findings were observed with optical microscope Nikon SMZ 1000/800 with magnifications of 1x to 6.3x. In two pebblestones, one decorated with parallel engravings, residues of ocher were detected in association with traces of use. In the third one, stained red dye was observed to form geometric patterns. Finally, reddish pigmentations were located on the cortical dorsal surface of a flint blade. To characterize chemically the coloring agent detected, macro-microscopically, Raman spectroscopy was used, a technique that allowed the study of the nature of the residues and the detection of additional organic materials whose presence must be related to post-depositional contaminations produced by the manipulation or/and surface exposure of artifacts

Ion Channel Involvement in Tumor Drug Resistance

Over 90% of deaths in cancer patients are attributed to tumor drug resistance. Resistance to therapeutic agents can be due to an innate property of cancer cells or can be acquired during chemotherapy. In recent years, it has become increasingly clear that regulation of membrane ion channels is an important mechanism in the development of chemoresistance. Here, we review the contribution of ion channels in drug resistance of various types of cancers, evaluating their potential in clinical management. Several molecular mechanisms have been proposed, including evasion of apoptosis, cell cycle arrest, decreased drug accumulation in cancer cells, and activation of alternative escape pathways such as autophagy. Each of these mechanisms leads to a reduction of the therapeutic efficacy of administered drugs, causing more difficulty in cancer treatment. Thus, targeting ion channels might represent a good option for adjuvant therapies in order to counteract chemo-resistance development

Early assembly proteins of the large ribosomal subunit of the thermophilic archaebacterium Sulfolobus. Identification and binding to heterologous rRNA species.

Studies of ribosome structure in thermophilic archaebacteria may provide valuable information on (i) the mechanisms involved in the stabilization of nucleic acid-protein complexes at high temperatures and (ii) the degree of evolutionary conservation of the ribosomal components in the primary kingdoms of cell descent. In this work we investigate certain aspects of RNA/protein interaction within the large ribosomal subunits of the extremely thermophilic archaebacterium Sulfolobus solfataricus. The ribosomal proteins involved in the early reactions leading to in vitro particle assembly have been identified; it is shown that they can interact with the RNA in a temperature-independent fashion, forming a thermally stable "core" particle that can subsequently be converted into complete 50 S ribosomes. Among the protein components of the core particle, those capable of independently binding to 23 and 5 S RNA species have also been identified. Finally, we show that the early assembly proteins of Sulfolobus large ribosomal subunits are able to interact cooperatively with 23 S RNAs from other archaebacteria or from eubacteria, thereby suggesting that RNA/protein recognition sites are largely conserved within prokaryotic ribosomes. By contrast, no specific binding of the archaebacterial proteins to eukaryotic RNA could be demonstrated

Detection of honey bee viruses in larvae of Vespa orientalis

The Oriental hornet (Vespa orientalis) is native to the southeastern Mediterranean, north-eastern and eastern Africa, the Middle East, Central Asia and it is well established in southern Italy. However, recent reports in Liguria, Trieste and Tuscany show great expansion of its areal probably due to climate change or involuntary anthropic actions. Adults feed on carbohydrates collected from fruit and nectar while brood is fed by workers with animal proteins (grasshoppers, flies, yellowjackets and bees). The interaction between the two species could lead to possible spillover of pathogens in both directions. Previous studies have already reported the presence of honey bee pathogens (virus, fungi and bacteria), in Vespae and have underlined their role in disseminating pathogens which could represent a threat for honey bees. Aim of this study was to detect the presence in V.orientalis of six honey bee viruses, more precisely Acute Bee Paralysis Virus (ABPV), Black Queen Cell Virus (BQCV), Chronic Bee Paralysis Virus (CBPV), Deformed Wing Virus (DWV), Kashmir Bee Virus (KBV), Sac Brood Virus (SBV), and to investigate possible transmission route. 30 adults and 29 larvae of V.orientalis and 2 pools of 10 honey bees (Apis mellifera ligustica) each were collected from the managed nest and apiary located both at the Department of Agricultural, Food and Forest Sciences-University of Palermo, and sent to the Department of Veterinary Medicine and Animal Productions- University of Naples “Federico II”. Samples were observed by stereomicroscope to assess possible alterations which could be indicative of the action of viruses and then subjected to multiplex PCR to detect viruses. No morphological alterations were identified despite the biomolecular results showed 25/30 adults and 24/29 larvae were infected with at least one virus (DWV). Adult samples presented also ABPV (19/30), BQCV (13/30), SBV (1/30); while larvae presented SBV (10/29), ABPV (5/29), BQCV (5/29). No sample resulted positive for CBPV and only 1/30 adult resulted positive for KBV. Honey bees’ positivities reflected those of the hornets: 2/2 DWV, 2/2 SBV, 2/2 BQCV and 1/2 ABPV. The viruses detected in our study are the most prevalent in apiaries across Italy and the overlapping of positivities between hornets and honey bees collected in the same site suggests possible transmission of honey bee viruses through ingestion of infected honey bees