Copper Dependent Modulation of α-Synuclein Phosphorylation in Differentiated SHSY5Y Neuroblastoma Cells.

Copper (Cu) dyshomeostasis plays a pivotal role in several neuropathologies, such as Parkinson's disease (PD). Metal accumulation in the central nervous system (CNS) could result in loss-of-function of proteins involved in Cu metabolism and redox cycling, generating reactive oxygen species (ROS). Moreover, neurodegenerative disorders imply the presence of an excess of misfolded proteins known to lead to neuronal damage. In PD, Cu accumulates in the brain, binds α-synuclein, and initiates its aggregation. We assessed the correlation between neuronal differentiation, Cu homeostasis regulation, and α-synuclein phosphorylation. At this purpose, we used differentiated SHSY5Y neuroblastoma cells to reproduce some of the characteristics of the dopaminergic neurons. Here, we reported that differentiated cells expressed a significantly higher amount of a copper transporter protein 1 (CTR1), increasing the copper uptake. Cells also showed a significantly more phosphorylated form of α-synuclein, further increased by copper treatment, without modifications in α-synuclein levels. This effect depended on the upregulation of the polo-like kinase 2 (PLK2), whereas the levels of the relative protein phosphatase 2A (PP2A) remained unvaried. No changes in the oxidative state of the cells were identified. The Cu dependent alteration of α-synuclein phosphorylation pattern might potentially offer new opportunities for clinical intervention.

Chemotrophic profiling of prokaryotic communities thriving on organic and mineral nutrients in a submerged coastal cave.

The geothermal system of the Salento peninsula (Italy) is characterized by the presence of many hydrogen sulfide-rich underground waters and thermal springs. We focused our attention on the submerged section of Zinzulùsa (Castro, Italy), a cave of both naturalistic and archaeological interest. In pioneer studies, some hypotheses about the origin of the sulfurous waters of this area were proposed. The most accredited one is that sulfate-enriched waters of marine origin infiltrate deep along bands with greater permeability, and warm-up going upwards, due to the geothermal gradient. During their route, marine waters interact with organic deposits and generate hydrogen sulfide as a result of sulfate reduction. To date, no studies have been conducted to elucidate the hydrogen sulfide origin in this site. The nature of reducing power and energy sources supporting microbial life in this submerged habitat is currently unknown. Here we present a multidisciplinary experimental approach aimed at defining geochemical features and microbiological diversity of the submerged habitat of Zinzulùsa cave. Our integrated data provide strong evidence that the sulfate content of the marine water and the activity of sulfate-reducing bacteria may account for the hydrogen sulfide content of the thermal springs. Anaerobic, sulfate-reducing, thermophilic Thermodesulfovibrio and hyperthermophilic Fervidobacterium genera show a high percentage contribution in 16S rRNA gene metabarcoding analyses, despite the mesophilic conditions of the sampling site. Besides, supported by PICRUSt functional analysis, we propose a chemotrophic model in which hydrocarbon deposits, entrapped in the stratifications of the seafloor, may be exploited by anaerobic oil-degrading bacteria as carbon and energy sources to sustain efficient hydrogen, sulfur, and nitrogen biogeochemical cycles. The Zinzulùsa hydrothermal site represents an ecosystem useful to obtain new insights into prokaryotic mutual interactions in oligotrophic and aphotic conditions, which constitute the largest environment of the biosphere.

Investigations of byzantine wall paintings in the abbey of Santa Maria di Cerrate (Italy) in view of their restoration.

In this paper, diagnostic analyses on 12th-13th century byzantine wall paintings in the abbey of Santa Maria di Cerrate (Southern Italy) were carried out preparatory to restoration work promoted by FAI (Fondo Ambiente Italiano). Both the pigments and the areas with a bleaching alteration in the frescoes were analysed using the energy dispersive X-ray fluorescence, the Raman spectroscopy and the scanning electron microscopy equipped with energy dispersive X-ray spectrometer. In particular, ED-XRF analyses were performed in situ on wall paintings, while Raman spectroscopy and SEM-EDX were accomplished on frescoes fragments. The results obtained allowed to determine the chemical composition of the pigments, helping to identify the original parts of the frescoes from the retouched ones. The work also provided important information about the historical-artistic context of the abbey. Archaeometric investigations have indeed revealed the pictorial technique used for the wall paintings of the abbey, as well as the presence of some very valuable pigments, such as lapis lazuli blue.

A silver nanoparticle-poly(methyl methacrylate) based colorimetric sensor for the detection of hydrogen peroxide.

A colorimetric sensor based on nanoparticles was developed for the detection of hydrogen peroxide. Nanoparticles were made using small sheets of poly(methyl methacrylate) (PMMA) and silver nitrate. The optical properties of the solution were characterized by spectrophotometer using the localized surface plasmon resonance (LSPR) phenomenon. The shape and size of the nanoparticles were obtained using a transmission electron microscope (TEM). Silver-poly(methyl methacrylate) nanoparticles solution (AgNP-PMMA) proved to be particularly sensitive to hydrogen peroxide compared to other analytes. This sensor provided a quick, practical and easy tool to detect hydrogen peroxide.

Ethane-Bridged Bisporphyrin Conformational Changes As an Effective Analytical Tool for Nonenzymatic Detection of Urea in the Physiological Range.

Conformational switching induced in ethane-bridged bisporphyrins was used as a sensitive transduction method for revealing the presence of urea dissolved in water via nonenzymatic approach. Bisporphyrins were deposited on solid quartz slides by means of the spin-coating method. Molecular conformations of Zn and Ni monometalated bis-porphyrins were influenced by water solvated urea molecules and their fluorescence emission was modulated by the urea concentration. Absorption, fluorescence and Raman spectroscopies allowed the identification of supramolecular processes, which are responsible for host-guest interaction between the active layers and urea molecules. A high selectivity of the sensing mechanism was highlighted upon testing the spectroscopic responses of bis-porphyrin films to citrulline and glutamine used as interfering agents. Additionally, potential applicability was demonstrated by quantifying the urea concentration in real physiological samples proposing this new approach as a valuable alternative analytical procedure to the traditionally used enzymatic methods.

Colloidal solution of silver nanoparticles for label-free colorimetric sensing of ammonia in aqueous solutions.

Silver nanoparticles were synthesized in the presence of saccharides and ammonia (NH3) in the concentration range from 10-2 to 103 ppm to develop an optical sensor for NH3 in aqueous solutions. Ammonia affects the features of the nanoparticles obtained in a concentration-dependent manner as determined by UV-vis absorption analysis and TEM observations. Structural and morphological analysis provides the basis for the production of a colorimetric label-free sensor for ammonia. Overall, surface plasmon resonance increases when ammonia concentration rises, although the functional trend is not the same over the entire investigated ammonia concentration range. Three different ranges have been identified: very low ammonia concentrations from 0.01 to 0.2 ppm, high ammonia concentrations from 20 to 350 ppm and, most importantly, the intermediate or physiological range of ammonia from 0.5 to 10 ppm.

Synthesis and Characterization of Mixed Iron-Manganese Oxide Nanoparticles and Their Application for Efficient Nickel Ion Removal from Aqueous Samples.

Mixed iron-manganese oxide nanoparticles, synthesized by a simple procedure, were used to remove nickel ion from aqueous solutions. Nanostructures, prepared by using different weight percents of manganese, were characterized by transmission electron microscopy, selected area diffraction, X-ray diffraction, Raman spectroscopy, and vibrating sample magnetometry. Adsorption/desorption isotherm curves demonstrated that manganese inclusions enhance the specific surface area three times and the pores volume ten times. This feature was crucial to decontaminate both aqueous samples and food extracts from nickel ion. Efficient removal of Ni2+ was highlighted by the well-known dimethylglyoxime test and by ICP-MS analysis and the possibility of regenerating the nanostructure was obtained by a washing treatment in disodium ethylenediaminetetraacetate solution.

Enhanced electrical conductivity of collagen films through long-range aligned iron oxide nanoparticles.

The development of biocompatible collagen substrates able to conduct electric current along specific pathways represent an appealing issue in tissue engineering, since it is well known that electrical stimuli significantly affects important cell behaviour, such as proliferation, differentiation, directional migration, and, therefore, tissue regeneration. In this work, a cheap and easy approach was proposed to produce collagen-based films exhibiting enhanced electrical conductivity, through the simple manipulation of a weak external magnetic trigger. Paramagnetic iron oxide nanoparticles (NPs) capped by a biocompatible polyethylene-glycol coating were synthetized by a co-precipitation and solvothermic method and sprayed onto a collagen suspension. The system was then subjected to a static external magnetic field in order to conveniently tune NPs organization. Under the action of the external stimulus, NPs were induced to orient along the magnetic field lines, forming long-range aligned micropatterns within the collagen matrix. Drying of the substrate following water evaporation permanently blocked the magnetic architecture produced, thereby preserving NPs organization even after magnetic field removal. Electrical conductivity measurements clearly showed that the presence of such a magnetic framework endowed collagen with marked conductive properties in specific directions. The biocompatibility of the paramagnetic collagen films was also demonstrated by MTT cell cytotoxicity test.

High ordered biomineralization induced by carbon nanoparticles in the sea urchin Paracentrotus lividus.

A surprising and unexpected biomineralization process was observed during toxicological assessment of carbon nanoparticles on Paracentrotus lividus (sea urchin) pluteus larvae. The larvae activate a process of defense against external material, by incorporating the nanoparticles into microstructures of aragonite similarly to pearl oysters. Aiming at a better understanding of this phenomenon, the larvae were exposed to increasing concentrations of carbon nanoparticles and the biomineralization products were analyzed by electron microscopy, x-ray diffraction and Raman spectroscopy. In order to evaluate the possible influence of Sp-CyP-1 expression on this biomineralization process by larvae, analyses of gene expression (Sp-CyP-1) and calcein labeling were performed. Overall, we report experimental evidence about the capability of carbon nanoparticles to induce an increment of Sp-CyP-1 expression with the consequent activation of a biomineralization process leading to the production of a new pearl-like biomaterial never previously observed in sea urchins.

Role of the cellular prion protein in the neuron adaptation strategy to copper deficiency.

Copper transporter 1 (CTR1), cellular prion protein (PrP(C)), natural resistance-associated macrophage protein 2 (NRAMP2) and ATP7A proteins control the cell absorption and efflux of copper (Cu) ions in nervous tissues upon physiological conditions. Little is known about their regulation under reduced Cu availability, a condition underlying the onset of diffused neurodegenerative disorders. In this study, rat neuron-like cells were exposed to Cu starvation for 48 h. The activation of Caspase-3 enzymes and the impairment of Cu,Zn superoxide dismutase (Cu,Zn SOD) activity depicted the initiation of a pro-apoptotic program, preliminary to the appearance of the morphological signs of apoptosis. The transcriptional response related to Cu transport proteins has been investigated. Notably, PrP(C) transcript and protein levels were consistently elevated upon Cu deficiency. The CTR1 protein amount was stable, despite a two-fold increase in the transcript amount, meaning the activation of post-translational regulatory mechanisms. NRAMP2 and ATP7A expressions were unvaried. The up-regulated PrP(C) has been demonstrated to enhance the cell Cu uptake ability by about 50% with respect to the basal transport, and so sustain the Cu delivery to the Cu,Zn SOD cuproenzymes. Conclusively, the study suggests a pivotal role for PrP(C) in the cell adaptation to Cu limitation through a direct activity of ion uptake. In this view, the PrP(C) accumulation observed in several cancer cell lines could be interpreted as a molecular marker of cell Cu deficiency and a potential target of therapeutic interventions against disorders caused by metal imbalances.

Stress response induced by carbon nanoparticles in Paracentrotus lividus.

Members of the 14-3-3 protein family are involved in many important cellular events, including stress response, survival and apoptosis. Genes of the 14-3-3 family are conserved from plants to humans, and some members are responsive to UV radiation. Despite the high rate of pollution generated by nano-pollutants, up to now their toxic effect on development is totally obscure. Embryos treated with carbon nanoparticles, RNA preparation, retro-transcription and quantitative real-time PCR. In response to carbon nano-particles exposure, the embryos collected 24 h later showed a 3,07-fold at 5x10(12) p and a 1,58-fold at 2.5x10(13) p and a 1,92-fold at 2.5x10(14) p increase in Pl14-3-3ε transcript levels compared with controls. The Pl14-3-3ε mRNA delocalization parallels the failure in archenteron elongation observed morphologically, as well as the lack of specific endoderm markers. Here, we report the isolation of the complete cDNA encoding the 14-3-3 epsilon isoform from Paracentrotus lividus sea urchin embryos, referred to as Pl14-3-3ε. Pl14-3-3ε mRNA levels were measured by RT-PCR during development and found to increase from the mesenchyme blastula to the prism stage. Our results confirm the involvement of 14-3-3ε in the stress response elicited by carbon nano-particles.

Monitoring of total and bioavailable heavy metals concentration in agricultural soils.

The aim of this paper is to evaluate total and bioavailable concentration of heavy metals in agricultural soils in order to estimate their distribution, to identify the possible correlations among toxic elements and the pollution sources, to distinguish the samples in relation to sampling site or to sampling depth, and to evaluate the available fraction providing information about the risky for plants. In particular, we reinvestigated total concentrations of As, Be, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, V, and Zn and available concentrations of As, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, and Zn in soil from Apulia (Southern Italy). Analytical results showed that total concentrations, for all soils, are in the range permitted by regulations in force in Italy, but some soils evidence slight enrichment of Cd, Cr, Cu, Pb, and Zn. All the heavy metals in the available fraction were below the detection limits of the analytical techniques used except Cu, Ni, Pb, and Zn.

Investigation of paroxysmal dystonia in a patient with multiple sclerosis: a transcranial magnetic stimulation study.

OBJECTIVE: To study the pathogenesis of paroxysmal dystonia affecting the right body side in a patient with a demyelinating lesion in the descending motor pathways, also involving the basal ganglia. METHODS: Single-pulse transcranial magnetic stimulation (TMS) was applied to study motor evoked potentials (MEPs) and the following silent periods (SPs) in the first dorsal interosseous muscle (FDI) of both sides and in the right extensor carpi radialis muscle (ECR) during voluntary contractions performed outside the dystonic attacks. During the dystonic paroxysms, single-pulse TMS was used to investigate the time course of MEPs and SPs in both FDI and ECR of the right side. Furthermore, paired-pulse TMS was applied at rest to investigate short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) in both FDI muscles. RESULTS: At rest SICI and ICF were normal in both motor cortices. During voluntary contraction the MEP was smaller and the SP was longer in the affected FDI than in the contralateral. During the paroxysms, the MEPs and SPs were suppressed in comparison with the responses elicited during voluntary contraction. CONCLUSIONS: These results fit well with the theory of ephaptic excitement of corticospinal axons for the pathogenesis of paroxysmal dystonia due to a demyelinating lesion. SIGNIFICANCE: Identification of the mechanisms underlying paroxysmal dystonia in demyelinating disorders extends our knowledge on the pathophysiology of dystonia.

Organic pollutants (PAHs, PCBs) in sediments from the Mar Piccolo in Taranto (Ionian Sea, Southern Italy).

Polychlorinated biphenyls (PCBs) and 17 parent polycyclic aromatic hydrocarbons (PAHs) were determined in surface sediments from nine stations in the Mar Piccolo of Taranto (Ionian Sea, Southern Italy). Total PAH concentrations ranged from 380 to 12,750 microg/kg d.w., while total PCB levels ranged from 2 to 1684 microg/kg d.w.; this values were higher than those found in others marine coastal areas of the Mediterranean Sea. For PAHs, low molecular weight/high molecular weight, phenanthrene/anthracene and fluoranthene/pyrene ratio were used for discriminating between pyrolitic and petroleum origin. Results showed that PAHs were mainly of pyrolitic origin. PCB and PAH levels in sediments were compared with Sediments Quality Guidelines (ERM-ERL, TEL-PEL indexes) for evaluation probable toxic effects on marine organism. Finally, ERM and PEL quotients were used to evaluate the degree to which chemicals exceed guidelines. Results suggest an ecotoxicological risk for benthic organisms mainly in the first inlet, where high concentrations of PCBs were found in sediments influenced by harbour activities.

Testing the photosynthetic bacterium Rhodobacter sphaeroides as heavy metal removal tool.

We present some preliminary results relevant to the ability of the purple non-sulphur bacterium Rhodobacter sphaeroides strain R26.1 to sequester heavy metals from contaminated growth media. The microorganism was chosen because of its significant tolerance to relatively high concentrations of the investigated ions Ni2+, Co2+, CrO4(2-), and MoO4(2-). In this paper the optimized conditions for the bacterial growth and the sample preparation used to infer the ability of the microorganism to cope with metal pollutants are presented. Elemental analysis has been performed by inductively coupled plasma atomic emission spectrometry previous mineralization of samples by a microwave system.

Natural sources and heavy metals.

PTS, PM10 and PM2.5 samples have been collected at a rural site of south-east Italy (40 degrees 20' 13" N; 18 degrees 6' 47" E) from June to October, 2004 to investigate natural and anthropogenic contributions on particulate matter and heavy metal mass concentrations. It is shown that sharp-peak particulate-matter concentrations have been recorded during most African dust outbreaks occurred over south-east Italy. In particular, PM10 concentrations exceeding the 24-hour limit value of 50 microg/m3 have been monitored during dust events. Al, Cd, Cr, Cu, Fe, Mn, V, Ni, Pb, and Zn metal concentrations have been evaluated by an inductively coupled plasma atomic emission spectrometer and Al mass concentrations >500 ng/m3 have been observed in PTS and PM10 samples during the advection of African dust particles. Accordingly to geochemical calculations Al, Fe, and Mn, have a significant crustal origin while, Cd, Cu, Pb, and Zn are of anthropogenic origin. Moreover, Fe resulted predominant in the coarse particle fraction, while Ni, Pb, V, and Zn were predominant in the fine particle fraction. It is also shown that Cd, Mn, Ni, Pb, and V concentrations never exceeded guide and/or limit values recommended by the World Health Organization and the European Council Directives.

Heavy metals in PM10 sampled in the urban area of Campi Salentina (Apulia, southern Italy).

The following paper shows results of PM10 level and Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn concentrations present in this fraction for filters collected in the urban area of Campi Salentina (Apulia, Southern Italy) in 2004 in order to inquire into air quality. PM10 and lead concentrations did not exceed the standard values sanctioned by Italian Legislature with average values equal to 36.54 +/- 14.57 microg x m(-3) and 9.19 +/- 5.24 ng x m(-3) respectively. Significant correlations have been found between the pairs Fe-Mn, Ni-V, Cr-Ni and Cd-Cr. This suggests that these metals have a similar pollution source probably due to metallurgical activity. Multivariate statistical analysis showed that it is possible to distinguish the PM10 samples collected in sampling periods with different meteorological conditions. Indeed, metals concentration increases for samples characterized by scarce rains or by winds prevailing from North or North-West and is reduced due to different meteorological conditions, although there are some exceptions.

Distribution and occurence of polycyclic aromatic hydrocarbons (PAHs) in sediments from the Mar Grande and Gulf of Taranto (Ionian Sea, southern Italy).

Marine sediments from the Mar Grande and Gulf of Taranto were analysed for 17 parent PAHs, with molecular weight from 128 to 278 Daltons. The analyses were performed by gas chromatography coupled to mass spectrometry (GC-MS). Total PAHs content in sediments ranged from 464 to 12522 microg kg(-1) dry wt for Mar Grande and from 593 to 72275 microg kg(-1) dry wt for Gulf of Taranto. The analytical results were compared with the published results for other coastal areas in the Mediterranean Sea. PAHs levels in the Gulf of Taranto sediments were the highest in the Mediterranean sea, while PAHs concentrations in Mar Grande were higher than the ones reported in the Adriatic and Cretan Sea and with the same order of magnitude of the ones known for coastal areas of the Western and the Eastern Mediterranean Sea. PAHs concentration ratios were consistent with the main source of these compounds, in most areas, being pyrolysis. Based on the comparison of both the individual and the total PAHs concentrations with proposed sediment quality guidelines, the acute biological effects on the marine organisms were probable, especially for the Gulf of Taranto, in which almost all PAHs concentrations in sediments were higher than the guidelines limit values. The statistical analysis effected by HCA and PCA methods was used in order to classify sediment samples and to identify accumulation areas.

Bilateral impairment of intracortical inhibition in delayed-onset posthemiplegic dystonia: pathophysiological implications.

OBJECTIVE: To study short interval intracortical inhibition (SICI) in a rare patient with segmental dystonia of the left upper limb due to a vascular lesion in the contralateral putamen without corticospinal tract involvement. METHODS: Paired-pulse transcranial magnetic stimulation (TMS) was applied to both hemispheres in a conditioning-test paradigm. Six interstimulus intervals (ISIs) and 4 conditioning stimulation intensities were investigated in two separate sessions. RESULTS: Motor evoked potentials upon single-pulse TMS were within the normal range, whereas paired-pulse TMS revealed major changes in cortical excitability, proving that SICI was bilaterally absent. CONCLUSIONS: The bilateral impairment of SICI cannot be considered the cause of dystonic contractions, but just a predisposing factor. SIGNIFICANCE: The absence of SICI might be regarded as a condition able to promote maladaptive plastic changes triggered by focal lesions in the putamen.

Botulinum toxin changes intrafusal feedback in dystonia: a study with the tonic vibration reflex.

To investigate the possible role of botulinum toxin (BT-A) injection in reducing muscle afferent feedback, we evaluated electrophysiologically 10 right-handed patients with writer's cramp before and 3 weeks after treatment. The ratio between pre- and postinjection values of maximal M-wave (M-max), maximal voluntary contraction (MVC), and tonic vibration reflex (TVR) were measured in the injected muscles (wrist flexors or extensors). In all the subjects, BT-A injection reduced the TVR more than the M-max and MVC (mean ratio +/- SD: TVR, 0.24 +/- 0.22; MVC, 0.59 +/- 0.32; M-max, 0.68 +/- 0.24; P = 0.003). Long-term evaluation of 2 patients disclosed that, after 7 months, when some clinical benefits persisted, M-max and MVC had fully recovered, whereas the TVR was still depressed. This special sensitivity of the TVR to suppression by BT-A injection could be mediated by the chemodenervation of intrafusal muscle fibers, leading to a reduction in spindle inflow to the central nervous system during vibration. The action on intrafusal fibers could alter sensorimotor integration, thus contributing to the clinical benefits of BT-A injection.