47 research outputs found
Freshwater ecotoxicity characterisation factor for metal oxide nanoparticles: A case study on titanium dioxide nanoparticle
The Life Cycle Assessment (LCA) methodology is widely applied in several industrial sectors to evaluate the environmental performance of processes, products and services. Recently, several reports and studies have emphasized the importance of LCA in the field of engineered nanomaterials. However, to date only a few LCA studies on nanotechnology have been carried out, and fewer still have assessed aspects relating to ecotoxicity. This is mainly due to the lack of knowledge in relation on human and environmental exposure and effect of engineered nanoparticles (ENPs). This bottleneck is continued when performing Life Cycle Impact Assessment, where characterization models and consequently characterization factors (CFs) for ENPs are missing. This paper aims to provide the freshwater ecotoxicity CF for titanium dioxide nanoparticles (nano-TiO2). The USEtox⢠model has been selected as a characterisation model. An adjusted multimedia fate model has been developed which accounts for nano-specific fate process descriptors (i.e. sedimentation, aggregation with suspended particle matter, etc.) to estimate the fate of nano-TiO2 in freshwater. A literature survey of toxicity tests performed on freshwater organism representative of multiple trophic levels was conducted, including algae, crustaceans and fish in order to collect relevant EC50 values. Then, the toxic effect of nano-TiO2 was computed on the basis of the HC50 value. Thus, following the principle of USEtox⢠model and accounting for nano-specific descriptors a CF for the toxic impact of freshwater ecotoxicity of 0.28 PAF day m3 kgâ 1 is proposed
Precocious Puberty and Covid-19 Into Perspective: Potential Increased Frequency, Possible Causes, and a Potential Emergency to Be Addressed
A significant increase in precocious puberty, rapidly progressive puberty and precocious menarche has been reported in Italy since the initial lockdown because of the pandemic, and this could represent a new emergency to be addressed during this pandemic. There is a need, therefore, for further understanding and research. Many causes could account for this. Initially, it was thought that the changes in life-style, in screen time, and sleeping habits could be the cause but if considered individually these are insufficient to explain this phenomenon. Likely, changes in central nervous mediators, and an increase in catecholamines could contribute as a trigger, however, these aspects are poorly studied and understood as well as the real perceptions of these children. Finally, staying more indoors has certainly exposed these children to specific contaminants working as endocrine disruptors which could also have had an effect. It would be of utmost importance to compare this phenomenon worldwide with appropriate studies in order to verify what is happening, and gain a new insight into the consequences of the covid-19 pandemic and into precocious puberty and for future prevention
Brain angioarchitecture and intussusceptive microvascular growth in a murine model of Krabbe disease
Abstract Defects of the angiogenic process occur in the
brain of twitcher mouse, an authentic model of human
Krabbe disease caused by genetic deficiency of lysosomal
b-galactosylceramidase (GALC), leading to lethal neurological
dysfunctions and accumulation of neurotoxic psychosine
in the central nervous system. Here, quantitative
computational analysis was used to explore the alterations
of brain angioarchitecture in twitcher mice. To this aim,
customized ImageJ routines were used to assess calibers,
amounts, lengths and spatial dispersion of CD31? vessels
in 3D volumes from the postnatal frontal cortex of twitcher
animals. The results showed a decrease in CD31
immunoreactivity in twitcher brain with a marked reduction
in total vessel lengths coupled with increased vessel
fragmentation. No significant changes were instead
observed for the spatial dispersion of brain vessels
throughout volumes or in vascular calibers. Notably, no
CD31? vessel changes were detected in twitcher kidneys in
which psychosine accumulates at very low levels, thus
confirming the specificity of the effect. Microvascular
corrosion casting followed by scanning electron microscopy
morphometry confirmed the presence of significant
alterations of the functional angioarchitecture of the brain
cortex of twitcher mice with reduction in microvascular
density, vascular branch remodeling and intussusceptive
angiogenesis. Intussusceptive microvascular growth, con-
firmed by histological analysis, was paralleled by alterations
of the expression of intussusception-related genes in
twitcher brain. Our data support the hypothesis that a
marked decrease in vascular development concurs to the
onset of neuropathological lesions in twitcher brain and
suggest that neuroinflammation-driven intussusceptive
responses may represent an attempt to compensate
impaired sprouting angiogenesis
Specific miRNAs Change After 3 Months of GH treatment and Contribute to Explain the Growth Response After 12 Months
Context: There is growing evidence of the role of epigenetic regulation of growth, and miRNAs potentially play a role.
Objective: The aim of this study is to identify changes in circulating miRNAs following GH treatment in subjects with isolated idiopathic GH deficiency (IIGHD) after the first 3 months of treatment, and verify whether these early changes can predict growth response.
Design and methods: The expression profiles of 384 miRNAs were analyzed in serum in 10 prepubertal patients with IIGHD (5 M, 5 F) at two time points before starting GH treatment (t-3, t0), and at 3 months on treatment (t+3). MiRNAs with a fold change (FC) >+1.5 or <-1.5 at t+3 were considered as differentially expressed. In silico analysis of target genes and pathways led to a validation step on 8 miRNAs in 25 patients. Clinical and biochemical parameters were collected at baseline, and at 6 and 12 months. Simple linear regression analysis and multiple stepwise linear regression models were used to explain the growth response.
Results: Sixteen miRNAs were upregulated and 2 were downregulated at t+3 months. MiR-199a-5p (p = 0.020), miR-335-5p (p = 0.001), and miR-494-3p (p = 0.026) were confirmed to be upregulated at t+3. Changes were independent of GH peak values at testing, and levels stabilized after 12 months. The predicted growth response at 12 months was considerably improved compared with models using the common clinical and biochemical parameters.
Conclusions: MiR-199a-5p, miR-335-5p, and miR-494-3p changed after 3 months of GH treatment and likely reflected both the degree of GH deficiency and the sensitivity to treatment. Furthermore, they were of considerable importance to predict growth response.Context: There is growing evidence of the role of epigenetic regulation of growth, and miRNAs potentially play a role.
Objective: The aim of this study is to identify changes in circulating miRNAs following GH treatment in subjects with isolated idiopathic GH deficiency (IIGHD) after the first 3 months of treatment, and verify whether these early changes can predict growth response.
Design and methods: The expression profiles of 384 miRNAs were analyzed in serum in 10 prepubertal patients with IIGHD (5 M, 5 F) at two time points before starting GH treatment (t-3, t0), and at 3 months on treatment (t+3). MiRNAs with a fold change (FC) >+1.5 or <-1.5 at t+3 were considered as differentially expressed. In silico analysis of target genes and pathways led to a validation step on 8 miRNAs in 25 patients. Clinical and biochemical parameters were collected at baseline, and at 6 and 12 months. Simple linear regression analysis and multiple stepwise linear regression models were used to explain the growth response.
Results: Sixteen miRNAs were upregulated and 2 were downregulated at t+3 months. MiR-199a-5p (p = 0.020), miR-335-5p (p = 0.001), and miR-494-3p (p = 0.026) were confirmed to be upregulated at t+3. Changes were independent of GH peak values at testing, and levels stabilized after 12 months. The predicted growth response at 12 months was considerably improved compared with models using the common clinical and biochemical parameters.
Conclusions: MiR-199a-5p, miR-335-5p, and miR-494-3p changed after 3 months of GH treatment and likely reflected both the degree of GH deficiency and the sensitivity to treatment. Furthermore, they were of considerable importance to predict growth response
Stereocontrolled synthesis of new iminosugar lipophilic derivatives and evaluation of biological activities
Iminosugars' similarity to carbohydrates determines the exceptional potential for this class of polyhydroxylated alkaloids to serve as potential drug candidates for a wide variety of diseases such as diabetes, lysosomal storage diseases, cancer, bacterial and viral infections. The presence of lipophilic substituents has a significant impact on their biological activities. This work reports the synthesis of three new pyrrolidine lipophilic derivatives O-alkylated in C-6 position. The biological activities of our iminosugars' collection were tested in two cancer cell lines and, due to the pharmaceutical potential, in the model yeast system Saccharomyces cerevisiae to assess their toxicity
Predicting needlestick and sharps injuries in nursing students: Development of the SNNIP scale
Š 2020 The Authors. Nursing Open published by John Wiley & Sons Ltd. Aim: To develop an instrument to investigate knowledge and predictive factors of needlestick and sharps injuries (NSIs) in nursing students during clinical placements. Design: Instrument development and cross-sectional study for psychometric testing. Methods: A self-administered instrument including demographic data, injury epidemiology and predictive factors of NSIs was developed between October 2018âJanuary 2019. Content validity was assessed by a panel of experts. The instrument's factor structure and discriminant validity were explored using principal components analysis. The STROBE guidelines were followed. Results: Evidence of content validity was found (S-CVI 0.75; I-CVI 0.50â1.00). A three-factor structure was shown by exploratory factor analysis. Of the 238 participants, 39% had been injured at least once, of which 67.3% in the second year. Higher perceptions of âpersonal exposureâ (4.06, SD 3.78) were reported by third-year students. Higher scores for âperceived benefitsâ of preventive behaviours (13.6, SD 1.46) were reported by second-year students
N-Bromosuccinimide-Induced Lactonization of Bicyclo[3.2.0]hept-3-en-6-ones
Lactonization of Bicyclo[3.2.0]hept-3-en-6-one