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Role of root exudates on the sorption of arsenate by ferrihydrite
No full textIron oxy-hydroxides in soil are known to have a large affinity for arsenate (As(V)) inorganic species. At the soil–root interface such mineral components are embedded by mucilaginous material that is secreted from continuously growing root cap cells. In order to determine the role of plant mucilages in As(V) sorption by iron oxy-hydroxides, we layered a calcium (Ca)-polygalacturonate network (CaPGA) on to amorphous iron (Fe) (III) hydroxide (ferrihydrite, Fh) particles. The scanning electron micrographs of the CaPGA network coating the ferrihydrite (Fh–CaPGA) show a regular structure with a honeycomb-like pattern where interlacing fibrils form a porous system. The FT-IR spectra of Fh–CaPGA suggest that CaPGA fibrils are retained by the surface Fe(III) nuclei of Fh through electrostatic interactions. The sorption experiments carried out at pH 4.3 and 5.8 indicated a smaller amount of As(V) sorbed by Fh–CaPGA than by Fh alone, being less after 3 and 24 hours of reaction by about 70 and 30%, respectively. The sorption of As(V) by Fh was also studied in the presence of caffeic acid (CAF), an important root exudate. Simultaneous sorption kinetics show that As(V) sorption by Fh is almost independent of CAF concentration, indicating a greater affinity of arsenate ions towards the Fh surfaces. However, the amount of As(V) sorbed by the Fh coated by CaPGA, in the presence of 0.25, 0.5 and 1.0 mm CAF, is markedly smaller by about 20, 27 and 40%, respectively, than that found in the As(V)–CAF-Fh ternary systems. This is caused mainly by redox reactions involving CAF and the surface Fe(III) nuclei of Fh leading to the formation of CAF oxidation products which prevent As(V) sorption
Release of lungworm larvae from snails in the environment: potential for alternative transmission pathways
No full textBackground: Gastropod-borne parasites may cause debilitating clinical conditions in animals and humans following the consumption of infected intermediate or paratenic hosts. However, the ingestion of fresh vegetables contaminated by snail mucus and/or water has also been proposed as a source of the infection for some zoonotic metastrongyloids (e.g., Angiostrongylus cantonensis). In the meantime, the feline lungworms Aelurostrongylus abstrusus and Troglostrongylus brevior are increasingly spreading among cat populations, along with their gastropod intermediate hosts. The aim of this study was to assess the potential of alternative transmission pathways for A. abstrusus and T. brevior L3 via the mucus of infected Helix aspersa snails and the water where gastropods died. In addition, the histological examination of snail specimens provided information on the larval localization and inflammatory reactions in the intermediate host.
Methodology/Principal Findings: Twenty-four specimens of H. aspersa received ~500 L1 of A. abstrusus and T. brevior, and were assigned to six study groups. Snails were subjected to different mechanical and chemical stimuli throughout 20 days in order to elicit the production of mucus. At the end of the study, gastropods were submerged in tap water and the sediment was observed for lungworm larvae for three consecutive days. Finally, snails were artificially digested and recovered larvae were counted and morphologically and molecularly identified. The anatomical localization of A. abstrusus and T. brevior larvae within snail tissues was investigated by histology. L3 were detected in the snail mucus (i.e., 37 A. abstrusus and 19 T. brevior) and in the sediment of submerged specimens (172 A. abstrusus and 39 T. brevior). Following the artificial digestion of H. aspersa snails, a mean number of 127.8 A. abstrusus and 60.3 T. brevior larvae were recovered. The number of snail sections positive for A. abstrusus was higher than those for T. brevior.
Conclusions: Results of this study indicate that A. abstrusus and T. brevior infective L3 are shed in the mucus of H. aspersa or in water where infected gastropods had died submerged. Both elimination pathways may represent alternative route(s) of environmental contamination and source of the infection for these nematodes under field conditions and may significantly affect the epidemiology of feline lungworms. Considering that snails may act as intermediate hosts for other metastrongyloid species, the environmental contamination by mucus-released larvae is discussed in a broader context
Evaluation of the impact of vitrification on the actin cytoskeleton of in vitro matured ovine oocytes by means of Raman microspectroscopy
No full textPurpose: Investigation of the changes induced by vitrification on the cortical F-actin of in vitro matured ovine oocytes by Raman microspectroscopy (RMS).
Methods: Cumulus-oocyte complexes, recovered from the ovaries of slaughtered sheep, were matured in vitro and vitrified following the Minimum Essential Volume method using cryotops. The cortical region of metaphase II (MII) oocytes (1) exposed to vitrification solutions but not cryopreserved (CPA-exp), (2) vitrified/warmed (VITRI), and (3) untreated (CTR) was analyzed by RMS. A chemical map of one quadrant of single CPA-exp, VITRI and CTR oocytes was, also, performed. In order to identify the region of Raman spectra representative of the cortical F-actin modification, a group of in vitro matured oocytes were incubated with latrunculin—A (LATA), a specific F-actin destabilizing drug, and processed for RMS analysis. Thereafter, all the oocytes were stained with rhodamine phalloidin and evaluated by fluorescence confocal microscopy. Raman spectra of the oocytes were, statistically, analyzed using Principal Component Analysis (PCA).
Results: The PCA score plots showed a marked discrimination between CTR oocytes and CPA-exp/ VITRI groups. The main differences, highlighted by PCA loadings, were referable to proteins (1657, 1440 and 1300 cm−1) and, as indicated by LATA experiments, also included the changes of the F-actin. Analysis by confocal microscopy revealed a clear alteration of the cortical F-actin of CPA-exp and VITRI oocytes confirming RMS results.
Conclusions: Raman microspectroscopy may represent an alternative analytical tool for investigating the biochemical modification of the oocyte cortex, including the F-actin cytoskeleton, during vitrification of in vitro matured ovine oocytes
<i>Opuntia</i> spp. biodiversity conservation and utilization on the Cape Verde Islands
No full textCactus pear is the common name of Opuntia
ficus-indica (L.) Mill., the arid-resistant plant that is grown worldwide for its multifunctional proprieties.
The paper gives an overview of local genetic resources
of Opuntia spp. and describes the results of the recent introduction of some O. ficus-indica varieties, hybrids and other cactaceas on Fogo Island during a cooperation international project carried out by the Italian Universities of Torino and Sassari aimed to build a sustainable supply chain for the local growers, in order to fight their extreme poverty and malnutrition. The ten introduced genotypes were selected from a repository located
Sardinia (Italy) held by the University of Sassari. They
were selected for fruits and/or cladodes productivity,
and potential use as livestock feed, and no invasive
behaviour.The propagation test started inMay 2007 and
data on the emerging and the growth of new cladodes
were recorded until March 2008: propagation was
carried out by cloning via cutting. Once planted and
identified, usual agrotechniques for Opuntia cultivation were applied and data on growth were periodically collected. To evaluate and compare the growth of the different genotypes, a productivity index was used.
Cladodes of the Nopalea genotype were significantly
smaller in size than all the other genotypes, in length
(20.50 cm), width (11.25 cm), and thickness (0.98 cm).
In the present study, the active preservation of biodiversity has become a tool to enhance sustainable
agroforestry
Interaction between bottlenose dolphin (<i>Tursiops truncatus</i>) and trammel nets in the Archipelago de La Maddalena, Italy
No full textInteractions between bottlenose dolphins (Tursiops truncatus) and fisheries are an increasing problem in the Mediterranean and effective management measures are needed. In order to assess the impact of dolphin interactions on artisanal trammel nets, we examine 354 fishing operations performed in waters of the Archipelago de La Maddalena (Italy). We evaluate whether interactions were related to the species composition of the catch and, using the local commercial value of the target species, we assess whether there was a real economic loss for fishermen. Bayesian models and partial correspondence analysis were used to determine the extent to which dolphin interactions and habitat differences contributed to variation in the species composition of catches. CPUE for fishing operations with no dolphin interactions was significantly higher than that for operations with dolphin interactions, although clearly this does not confirm a direct causal link, and associated economic loss was estimated to be non-significant. Geographic location, season, depth of seabed, moon phase, and mesh size were all important factors affecting the amount and species composition of the catch. Our results suggest that it is likely that these differences in species composition are due to a mixture of habitat and dolphin-induced effects
I Sistemi idrici come organismi cibernetici: un approccio relazionale nella pianificazione di laghi artificiali e aree umide costiere
No full textThe research deals with river basin planning considering both the relations between water, wetlands, and landscape, and the crisis caused by a design approach still conceiving water infrastructure elements – i.e. dams, water supply and treatment, and flood prevention systems – as separate and unrelated to the receiving water system, to its wetlands, and to landscape with its environmental, cultural, historic, and human features.
Particular attention is given to artificial reservoirs and coastal wetlands insomuch as they represent nodal points of drainage basins, as they reflect territorial dynamics of water, and as they are cybernetic organisms representing a deeply interconnected socio-environment. The study examines two cases: the Boadella-Aiguamolls de l'Empordà system in Catalonia and the Cuga-Calich system in Sardinia.
The research centres on the processes of review and structuration of landscape-water infrastructure relation, organizing its content based on multiple territorial layerings, within which complex issues – like flood risk, poor quality of water, low efficiency of water supply network, degradation of environment and landscape, or social denial of waterscapes – become driving forces in the definition of potential planning strategies rather than being mere outcomes
Influenza della presenza di metalli e antiossidanti sullo sviluppo e decorso clinico della poliposi rinosinusale
No full textAim: Prevalence of nasal polyposis is about 4%, but its pathogenesis is still unknown. The aim of this work is to evaluate the presence of metals in nasal polyps tissues and to investigate the role of trace elements and antioxidants on nasal polyposis developing and clinic.
The metals and antioxidant enzyme levels measured in nasal polyps of 58 patients were compared with the levels measured in nasal biopsies of healthy patients.
Methods: 58 adult patients with nasal polyposis and 29 healthy patients were prospectively enrolled from June 2012 to August 2014. Clinical disease severity was measured by computed tomography and endoscopy (Stammberger score). Polyp samples and nasal mucosa were collected by outpatient biopsy during FESS and analysed through electron microscopy TEM and SEM to analyze ultra-structural morphology. In each sample we searched metals (cadmium, copper, aluminium, zinc, lead, manganese, selenium, cobalt and iron) through high resolution mass spectrometry (HR-ICP-MS).
Results: With electron microscopy we observed significant ultrastructural alterations in the samples of polyps compared to samples of healthy mucous. All metals have been detected in high concentrations in healthy samples compared to polyps samples (p< 0,001).
Conclusion: Results analyzed by the various methods used in the study may be a demonstration of an improvement of oxidative stress that can influence rhinosinusal polyposis developing and clinic
Indagini di base per l'impiego di <i>Entomophaga maimaiga</i> nel controllo di <i>Lymantria dispar</i> in ambiente mediterraneo
No full textLymantria dispar larvae were collected in 20 oak stands in Sardinia to evaluate mortality factors. Collected larvae were reared in the laboratory on artificial diet until they died or pupated. Larval mortality ranged from 17,5% to 100%. Parasitoids that killed larvae were identified and the remaining larvae were evaluated for presence of pathogens. The tachinid Blepharipa pratensis was the most frequently observed and caused up to 57% mortality. The viral pathogen LdNPV caused mortality up to 37,5%. We recorded the presence of Beauveria bassiana as well as the microsporidium Nosema portugal, which was previously identified as Nosema lymantriae. The fungal entomopathogen Entomophaga maimaiga was not collected from the host populations surveyed. This fungus is a virulent and very host specific pathogen of the gypsy moth. We started bioassays to verify the effectiveness against gypsy moth larvae from Sardinia and other parts of Italy. Two methodologies were followed: larvae were exposed to contaminated soil containing E. maimaiga azygospores; larvae were sunk in a water suspension containing the fungus azygospores. Mortality caused by fungus was 4,16% in 2012, 3% in 2013 and 2,06% in 2014 for the first method and 4.70% for the second method. In order to exclude negative effects for the environment and lay the foundations for the introduction of E. maimaiga in Sardinia we verified the action of the fungus against other lepidopteran larvae: none of them were killed by the fungus
Susceptibility to complex diseases in Sardinian population explained by Runs of Homozygosity and genomic regions under positive selection
No full textAim: 1)Confirm and detail the homogeneity of the Sardinian population at interregional level based on the analysis "genome-wide" through the use of "Runs of Homozygosity" (RoHS);2) infer the genetic history of the Sardinian population by estimating the level of genetic background of the common ancestry within the island and compare it to the Italian peninsula; 3)Identify indicators of positive selection.
Methods: About single nucleotide polymorphisms (SNPs) genotyped in 1077 Sardinian individuals were used to investigate the genetic population structure, as well as to estimate RoH and Extended Haplotype Homozygosity regions. We used four different methods: fixation index, inflaction factor, multi-dimensional scaling and ancestry estimation. we were able to highlight, as expected from a genetic isolate, the high internal homogeneity of the island. Comparing Sardinia to mainland Italy through several classes of RoH.
Conclusion: We confirmed the high genetic homogeneity of Sardinia and we have shown that the
genome of the Sardinians has mean inbreeding coefficients which are higher than those of mainland Italians. Furthermore, the Sardinian’s genome still preserves traces of the elaborate demographic history of the island. In addition, we observed that some genomic regions showing signs of positive selection
Effects of homeopathic mother tinctures on breath alcohol testing
No full textIn some countries, it is illegal to drive with any detectable amount of alcohol in blood; in others, the legal limit is 0.5 g/L or lower. Recently, some defendants charged with driving under the influence of alcohol and have claimed that positive breath alcohol test results were due to the ingestion of homeopathic mother tinctures. These preparations are obtained by maceration, digestion, infusion, or decoction of herbal material in hydroalcoholic solvent. A series of tests were conducted to evaluate the alcoholic content of three homeopathic mother tinctures and their ability to produce inaccurate breath alcohol results. Nine of 30 subjects gave positive results (0.11–0.82 g/L) when tests were taken within 1 min after drinking mother tincture. All tests taken at least 15 min after the mother tincture consumption and resulted in alcohol-free readings. An observation period of 15–20 min prior to breath alcohol testing eliminates the possibility of false-positive results