73 research outputs found
Nonsense-mediated decay mechanism is a possible modifying factor of clinical outcome in nonsense cd39 beta thalassemia genotype
Nonsense-mediated mRNA decay (NMD) is a surveillance system to prevent the synthesis of non-functional proteins. In β-thalassemia, NMD may have a role in clinical outcome. An example of premature translation stop codons appearing for the first time is the β-globin cd39 mutation; when homozygous, this results in a severe phenotype. The aim of this study was to determine whether the homozygous nonsense cd39 may have a milder phenotype in comparison with IVS1,nt110/cd39 genotype. Genotypes have been identified from a cohort of 568 patients affected by β-thalassemia. These genotypes were compared with those found in 577 affected fetuses detected among 2292 prenatal diagnoses. The nine most common genotypes, each with an incidence rate of 1.5% or over, and together accounting for 80% of genotype frequencies, underwent statistical analysis. Genotype prevalence was calculated within the overall group. Results are expressed as proportions with 95% confidence intervals; P≤0.05 was considered statistically significant. A binomial distribution was assumed for each group; z-tests were used to compare genotype frequencies observed in the patient group with frequencies in the affected fetus group. In the absence of selecting factors, prevalence of these two genotypes was compared between a cohort of 568 β-thalassemia patients (PTS) and 577 affected fetuses (FOET) detected during the same period. IVS1,nt110/cd39 was significantly more prevalent in FOET than PTS (P<0.0001), while there was no significant difference in prevalence of cd39/cd39 in FOET compared with PTS (P=0.524). These results suggest a cd39 genotype NMD mechanism may be associated with improved clinical outcomes in thalassemia major
Potential roles of extracellular vesicles in brain cell-to-cell communication
Potential roles of extracellular vesicles in brain cell-to-cell communication
Extracellular vesicles (EVs) are released into thè extracellular space from both cancer and normal
brain cells, and are probably able to modify thè phenotypic properties of receiving cells1. EVs
released from astrocytes and neurons contain FGF2 and VEGF2'3 and induce a 'blood-brain
barrier' (BBB) phenotype in cultured brain capillary endothelial cells (BCECs, unpublished results),
On thè other hand, EVs from G26/24 oligodendroglioma induce apoptosis in neurons and
astrocytes4-5. These effects are probably due to Fas Ligand and TRAIL, present in G26/24
vesicles4-5. Moreover, G26/24 EVs contain extracellular matrix remodeling proteases (such as
ADAMTS)6, H1.0 histone protein, and H1.0 mRNA7. In particular, we previously hypothesized that
G26/24 cells, and tumor cells in generai, can escape differentiation cues, and continue to
proliferate by eliminating proteins, such as thè H1° linker histone (and its mRNA)7, which could
otherwise block proliferation.
To study vesicle release in a System that can better resemble in vivo conditions, astrocytes and
BCECs were cultured on poly-L-lactic acid (PLLA) scaffolds and tested for their ability to grow and
survive on this three-dimensional structures. We analyzed in parallel thè celi growth in 2D and 3D
culture systems and observed thè differences in celi morphology by fluorescence analysis: threedimensional
scaffolds have thè ability to guide celi growth, provide support, encourage celi
adhesion and proliferation. Astrocytes8 and BCECs (unpublished results) adapted well to these
porous matrices, not only remaining on thè surface, but also penetrating inside thè scaffolds.
EVs released by astrocytes in these scaffolds are probably exosomes, as suggested by
transmission electron microscopy pictures, and by thè presence of intracellular structures
resembling multivesicular bodies. This 3D celi culture System could be further enriched to host
different brain celi types, in order to set, for example, an in vitro model of BBB, that may be useful
for drug delivery studies, and for thè formulation of new therapeutic strategies for thè treatment of
neurological diseases.
References
[1] Schiera, G., Di Liegro, C.M., Di Liegro I. Int J Mol Sci. 2017, 18(12). pii: E2774.
[2] Schiera, G., Proia, P., Alberti, C., Mineo, M., Savettieri, G., Di Liegro, I., 2007. J Celi Mol Med. 2007,
111(6), 1384-94.
[3] Proia, P., Schiera, G., Mineo, M., Ingrassia, A.M. Santoro, G., Savettieri, G., Di Liegro, I. Int J Mol Med.
2008, 21(1), 63-7.
[4] D'Agostino, S., Salamene, M., Di Liegro, I., Vittorelli, ML, Int J Oncol. 2006, 29(5), 1075-85.
[5] Lo Cicero, A., Schiera, G., Proia, P., Saladino, P., Savettieri, G., Di Liegro, C.M., Di Liegro, I. Int J Oncol.
2011,39(6): 1353-7.
[6] Lo Cicero, A., Majkowska, I., Nagase, H., Di Liegro, I., Troeberg, L., Matrix Biol. 2012, 31(4), 229-33.
[7] Schiera, G., Di Liegro, C.M., Saladino, P., Pitti, R., Savettieri, G., Proia, P., Di Liegro, I. Int J Oncol. 2013,
43(6), 1771-6.
[8] Carfì Pavia, F., Di Bella, M.A., Brucato, V., Blanda, V., Zummo, F., Vitrano, I., Di Liegro, C.M., Ghersi, G.,
Di Liegro, I., Schiera, G. Mol Med Rep. 2019 [Epub ahead of print].
[9] Di Bella MA, Zummo F., Carfì Pavia F., Brucato V., Di Liegro I., Schiera G. 2017, In: Microscopy and
Imaging Science: practical approaches to applied research and education, pp 260-264. Ed: A. MĂ©ndez-Vilas
Publisher, Formatex Research Center (Spain), ISBN-13, 978-84-942134-9-6
RP1 Dominant p.Ser740* Pathogenic Variant in 20 Knowingly Unrelated Families Affected by Rod–Cone Dystrophy: Potential Founder Effect in Western Sicily
: Background and Objectives. Retinitis pigmentosa (RP) is the most common inherited rod-cone dystrophy (RCD), resulting in nyctalopia, progressive visual field, and visual acuity decay in the late stages. The autosomal dominant form (ADRP) accounts for about 20% of RPs. Among the over 30 genes found to date related to ADRP, RP1 pathogenic variants have been identified in 5-10% of cases. In a cohort of RCD patients from the Palermo province on the island of Sicily, we identified a prevalent nonsense variant in RP1, which was associated with ADRP. The objective of our study was to analyse the clinical and molecular data of this patient cohort and to evaluate the potential presence of a founder effect. Materials and Methods. From 2005 to January 2023, 84 probands originating from Western Sicily (Italy) with a diagnosis of RCD or RP and their relatives underwent deep phenotyping, which was performed in various Italian clinical institutions. Molecular characterisation of patients and familial segregation of pathogenic variants were carried out in different laboratories using Sanger and/or next-generation sequencing (NGS). Results. Among 84 probands with RCD/RP, we found 28 heterozygotes for the RP1 variant c.2219C>G, p.Ser740* ((NM_006269.2)*, which was therefore significantly prevalent in this patient cohort. After a careful interview process, we ascertained that some of these patients shared the same pedigree. Therefore, we were ultimately able to define 20 independent family groups with no traceable consanguinity. Lastly, analysis of clinical data showed, in our patients, that the p.Ser740* nonsense variant was often associated with a late-onset and relatively mild phenotype. Conclusions. The high prevalence of the p.Ser740* variant in ADRP patients from Western Sicily suggests the presence of a founder effect, which has useful implications for the molecular diagnosis of RCD in patients coming from this Italian region. This variant can be primarily searched for in RP-affected subjects displaying compatible modes of transmission and phenotypes, with an advantage in terms of the required costs and time for analysis. Moreover, given its high prevalence, the RP1 p.Ser740* variant could represent a potential candidate for the development of therapeutic strategies based on gene editing or translational read-through therapy for suppression of nonsense variants
Long-term treatment with deferiprone enhances left ventricular ejection function when compared to deferoxamine in patients with thalassemia major
Transfusion and iron chelation treatment have significantly reduced morbidity and improved survival of patients with thalassemia major. However, cardiac disease continues to be the most common cause of death.
We report the left-ventricular ejection fraction, determined by echocardiography, in one hundred sixtyeight
patients with thalassemia major followed for at least 5 years who received continuous monotherapy with
deferoxamine (N = 108) or deferiprone (N = 60). The statistical analysis, using the generalized estimating
equations model, indicated that the group treated with deferiprone had a significantly better left-ventricular
ejection fraction than did those treated with deferoxamine (coefficient 0.97; 95% CI 0.37; 1.6, p = 0.002).
The heart may be particularly sensitive to iron-induced mitochondrial damage because of the large number of
mitochondria and its low level of antioxidants. Deferiprone, because of its lower molecular weight, might cross
into heart mitochondria more efficiently, improving their activity and, thereby, myocardial cell function.
Our findings indicate that the long-term administration of deferiprone significantly enhances left-ventricular
function over time in comparison with deferoxamine treatment. However, because of limitations related to
the design of this study, these findings should be confirmed in a prospective, randomized clinical trial
HE-LHC: The High-Energy Large Hadron Collider – Future Circular Collider Conceptual Design Report Volume 4
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries
FCC-ee: The Lepton Collider: Future Circular Collider Conceptual Design Report Volume 2
In response to the 2013 Update of the European Strategy for Particle Physics, the Future Circular Collider (FCC) study was launched, as an international collaboration hosted by CERN. This study covers a highest-luminosity high-energy lepton collider (FCC-ee) and an energy-frontier hadron collider (FCC-hh), which could, successively, be installed in the same 100 km tunnel. The scientific capabilities of the integrated FCC programme would serve the worldwide community throughout the 21st century. The FCC study also investigates an LHC energy upgrade, using FCC-hh technology. This document constitutes the second volume of the FCC Conceptual Design Report, devoted to the electron-positron collider FCC-ee. After summarizing the physics discovery opportunities, it presents the accelerator design, performance reach, a staged operation scenario, the underlying technologies, civil engineering, technical infrastructure, and an implementation plan. FCC-ee can be built with today’s technology. Most of the FCC-ee infrastructure could be reused for FCC-hh. Combining concepts from past and present lepton colliders and adding a few novel elements, the FCC-ee design promises outstandingly high luminosity. This will make the FCC-ee a unique precision instrument to study the heaviest known particles (Z, W and H bosons and the top quark), offering great direct and indirect sensitivity to new physics
FCC Physics Opportunities: Future Circular Collider Conceptual Design Report Volume 1
We review the physics opportunities of the Future Circular Collider, covering its e+e-, pp, ep and heavy ion programmes. We describe the measurement capabilities of each FCC component, addressing the study of electroweak, Higgs and strong interactions, the top quark and flavour, as well as phenomena beyond the Standard Model. We highlight the synergy and complementarity of the different colliders, which will contribute to a uniquely coherent and ambitious research programme, providing an unmatchable combination of precision and sensitivity to new physics
HE-LHC: The High-Energy Large Hadron Collider: Future Circular Collider Conceptual Design Report Volume 4
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries
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