193 research outputs found
Nanoparticles and higher plants
Abstract Nanomaterials and nanotechnology have been widely applied in the world in this last decade. Nanotechnology provides the tool and the technological platforms for the study and transformation of biological systems. Few studies have focused on the effects and mechanisms of nanomaterials on plants. The results of these studies have been reported with the aim to provide further insight into connections between plants and nanomaterials
Toxicological assays with Vicia faba L. for monitoring bioremediation processes of soils contaminated by polycyclic aromatic hydrocarbons and total petroleum hydrocarbons
The ecotoxicological assays are used both in the assessment of the toxicity of various matrices and to estimate the effectiveness of the remediation of a matrix over time.
Several organisms can be employed in eco-toxicological tests in the lab, or can be observed in their natural environment representing indicators of specific environmental conditions.
Higher plants can be exploited as good indicators of the quality of different matrices and used both as a standard during remediation processes of contaminated soil but also in the evaluation of soil quality. In fact, the only chemical characterization of a polluted soil does not allow to predict the real toxicity of the matrix, that may depend on the original pollutants, on degradations intermediates, often unknown, and on the synergic actions of the different toxicants.
The aim of this research was to evaluate the efficacy of the process abatement of the initial concentration, in a contaminated soil, of polycyclic aromatic hydrocarbons (PAHs, 6480 ppm) and of total petroleum hydrocarbons (TPHs, 18347 ppm) by means of a biopile in terms of reduction of the final matrix toxicity. For this reason soil samples at different time intervals from the beginning of treatment in biopile were collected and chemically characterized, for the monitoring and assessment of the possible phyto-genotoxic effects on the model system Vicia faba L. The biopile treatment determined the depletion of PAHs and TPHs below 10 and 100 ppm respectively. Biological parameters such as germination and root elongation were also evaluated as well as the possible genotoxic effects by means of cytological analysis of mitotic behaviour of root meristem, based on detection of chromosomal aberrations in mitotic cells, and of micronuclei formation, detectable in interphase cells. As additionally genotoxicity endpoint, cytohistochemical detection of in situ DNA fragmentation in root apices was achieved by TUNEL reaction, that allows to recognize both single and double-strand breaks at cellular and tissue level.
Comparing the obtained results it was found that the phyto-genotoxic effect of contaminated soil was completely depleted after treatment in biopile and Vicia faba was found to be a good approach for monitoring the biodegradation processes and the toxicity of these solid matrices at the end of a bio-based decontamination approach.
Keywords: genotoxicity, phytotoxicity, polycyclic aromatic hydrocarbons, total petroleum hydrocarbon
Impact of TiO2 nanoparticles on Vicia narbonensis L.: potential toxicity effects
This work was aimed to provide further information about toxicology of TiO2 nanoparticles (NPs) on Vicia narbonensis L., considering different endpoints. After exposure to TiO2 nanoparticle suspension (mixture of rutile and anatase, size <100 nm) at four different concentrations (0.2, 1.0, 2.0 and 4.0 ‰), the seeds of V. narbonensis were let to germinate in controlled environmental conditions. After 72 h, the extent of the success of the whole process (seed germination plus root elongation) was recorded as the vigour index, an indicator of possible phytotoxicity. After the characterisation of the hydric state of different materials, oxidative stress and enzymatic and nonenzymatic antioxidant responses were considered as indicators of possible cytotoxicity and to assess if damage induced by TiO2 NPs was oxidative stress-dependent. Cytohistochemical detection of in situ DNA fragmentation as genotoxicity endpoint was monitored by TUNEL reaction. The treatments with TiO2 NPs in our system induced phytotoxic effects, ROS production and DNA fragmentation. The nonenzymatic and enzymatic antioxidant responses were gradually and differentially activated and were able to maintain the oxidative damage to levels not significantly different from the control. On the other hand, the results of DNA fragmentation suggested that the mechanisms of DNA repair were not effective enough to eliminate early genotoxicity effects
Aging, Cognitive Decline and Hearing Loss: Effects of Auditory Rehabilitation and Training with Hearing Aids and Cochlear Implants on Cognitive Function and Depression among Older Adults
A growing interest in cognitive effects associated with speech and hearing processes is spreading throughout the scientific community essentially guided by evidence that central and peripheral hearing loss is associated with cognitive decline. For the present research, 125 participants older than 65 years of age (105 with hearing impairment and 20 with normal hearing) were enrolled, divided into 6 groups according to their degree of hearing loss and assessed to determine the effects of the treatment applied. Patients in our research program routinely undergo an extensive audiological and cognitive evaluation protocol providing results from the Digit Span test, Stroop color-word test, Montreal Cognitive Assessment and Geriatric Depression Scale, before and after rehabilitation. Data analysis was performed for a cross-sectional and longitudinal study of the outcomes for the different treatment groups. Each group demonstrated improvement after auditory rehabilitation or training on shortand long-term memory tasks, level of depression and cognitive status scores. Auditory rehabilitation by cochlear implants or hearing aids is effective also among older adults (median age of 74 years) with different degrees of hearing loss, and enables positive improvements in terms of social isolation, depression and cognitive performance
Phytoremediation for improving the quality of effluents from a conventional tannery wastewater treatment plant
In the present study, the quality of effluents from a conventional wastewater treatment plant in Italy has been analyzed. Residual level of contamination by 4-nnonylphenol, mono- and di-ethoxylated nonylphenols has been recorded in the effluents that resulted to be also phytotoxic and genotoxic. The possibility of exploiting phytoremediation as a sustainable tertiary treatment for the depletion of the priority pollutants and for the reduction in the residual toxicity has been verified at mesocosm scale.
The phyto-based treatment has been performed by the exploitation of Phragmites australis by either a bacterialassisted and not assisted approach. In relation to the bacterial-assisted approach, two new bacterial strains, capable of using the nonylphenols as a sole carbon source, have been isolated. One was identified as a plant growth-promoting rhizobacteria (PGPR) belonging to the Stenotrophomonas species, and the second one was classified as a Sphingobium species strain. Both strains were independently bioaugmented in the P. australis rhizosphere. In relation to the not assisted approach, the phyto-based process determined 87, 70 and 87 % for 4-n-nonylphenol, mono-ethoxylated nonylphenols and di-ethoxylated nonylphenols, respectively. The toxicological assessment of the process evidenced the complete depletion of either the phytotoxicity or the genotoxicity of the treated effluents.
With reference to the bacterial-assisted approach, the PGPR Stenotrophomonas species strain resulted to be capable of significantly increasing the efficiency of the phyto-based process in nonylphenol depletion up to 88 % for the 4-n-nonylphenol, 84 % for the mono-ethoxylated nonylphenol and 71 % for the di-ethoxylated nonylphenol
Chromatin organisation and computer aided karyotyping of Triticum durum Desf. cv. Timilia
Abstract The tribe Triticeae includes three cereal genera Secale, Hordeum and Triticum and because of their economical and agronomical importance, the relationships among species on the tribe have been extensively investigated. The wild wheat relatives are an important source of genetic variation for cultivated species and wheat is an important crop of the mediterranean region. Banding pattern of metaphase chromosomes and nuclear DNA content in root meristematic cells of an old sicilian landrace "Timilia" were determined. Microdensitometric evaluation of nuclear absorption at different thresholds of optical density indicates the organization of chromatin in the interphase nuclei. Chromosome morphometric data, karyotype simmetry, the TF% values and Syi indices were determined. The results are compared with the data of other durum wheat varieties as Capeiti and Simeto
Karyological and molecular characterisation of subgenus Vicia (Fabaceae)
In the present report, we have analysed the subgenus Vicia by karyological and molecular approaches with the aim to clarify
the relationships among Vicia species included in this subgenus by previously evidenced morphological investigations.
Multivariate analysis using several karyomorphological parameters in addition to symmetry indices has allowed the
construction of a dendrogram of linkage distances very useful to compare and to include in a phylogenetic tree obtained by
internal transcribed spacer (ITS) rDNA sequences. Moreover, a separate analysis was performed combining our molecular
data on ITS sequences with those reported in the literature for the section Vicilla. Our analyses partly confirm the
monophyletic status of the various sections in which the subgenus Vicia has been divided, however questioning, in some
cases, the real need to maintain all the nine sections so far accepted and the placement of some individual species in the two
subgenera Vicia and Vicilla
Polycyclic aromatic hydrocarbon-contaminated soils: bioaugmentation of autochthonous bacteria and toxicological assessment of the bioremediation process by means of Vicia faba L.
Two bacterial strains, Achromobacter sp. (ACH01) and Sphingomonas sp. (SPH01), were isolated from a heavily polycyclic aromatic hydrocarbon (PAH)-contaminated soil (5431.3 ± 102.3 ppm) for their capacity to use a mixture of anthracene, pyrene, phenanthrene and fluorene as sole carbon sources for growth and for the capacity to produce biosurfactants. The two strains were exploited for bioaugmentation in a biopile pilot plant to increase the bioavailability and the degradation of the residual PAH contamination (99.5 ± 7.1 ppm) reached after 9 months of treatment. The denaturing gel gradient electrophoresis (DGGE) profile of the microbial ecology of the soil during the experimentation showed that the bioaugmentation approach was successful in terms of permanence of the two strains in the soil in treatment. The bioaugmentation of the two bacterial isolates positively correlated with the PAH depletion that reached 7.9 ± 2 ppm value in 2 months of treatment. The PAH depletion was assessed by the loss of the phyto-genotoxicity of soil elutriates on the model plant Vicia faba L., toxicological assessment adopted also to determine the minimum length of the decontamination process for obtaining both the depletion of the PAH contamination and the detoxification of the soil at the end of the process. The intermediate phases of the bioremediation process were the most significant in terms of toxicity, inducing genotoxic effects and selective DNA fragmentation in the stem cell niche of the root tip. The selective DNA fragmentation can be related to the selective induction of cell death of mutant stem cells that can compromise offsprings
Transrectal ultrasonography in infertile patients with persistently elevated bacteriospermia
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