359 research outputs found
Polarization Effect on the Performance of On-Chip Wireless Optical Point-to-Point Links
Optical on-chip wireless interconnection is an emerging technology that aims to overcome the communication bottleneck in computing architectures and in which multiple processing units are exploited for data-intensive applications. In this work, we propose an integrated dielectric Vivaldi antenna, which exhibits the same gain performances for both TE and TM input polarizations. Point-to-point on-chip communication links between two Vivaldi antennas are analyzed. Moreover, the effect of wave polarization on the link performances is numerically studied in on-chip multilayer structures in connection with the multilayer characteristic parameters, i.e., cladding layer thickness and refractive index. The numerical results show that, with the same antenna gain, TM polarization is affected by lower propagation losses when suitable cladding layer thickness and refractive index are considered
The gustin (CA6) gene polymorphism, rs2274333 (A/G), as a mechanistic link between PROP tasting and fungiform taste papilla density and maintenance
Taste sensitivity to PROP varies greatly among individuals and is associated with polymorphisms in the bitter receptor gene TAS2R38, and with differences in fungiform papilla density on the anterior tongue surface. Recently we showed that the PROP non-taster phenotype is strongly associated with the G variant of polymorphism rs2274333 (A/G) of the gene that controls the salivary trophic factor, gustin. The aims of this study were 1) to investigate the role of gustin gene polymorphism rs2274333 (A/G), in PROP sensitivity and fungiform papilla density and morphology, and 2) to investigate the effect of this gustin gene polymorphism on cell proliferation and metabolic activity. Sixty-four subjects were genotyped for both genes by PCR techniques, their PROP sensitivity was assessed by scaling and threshold methods, and their fungiform papilla density, diameter and morphology were determined. In vitro experiments examined cell proliferation and metabolic activity, following treatment with saliva of individuals with and without the gustin gene mutation, and with isolated protein, in the two iso-forms. Gustin and TAS2R38 genotypes were associated with PROP threshold (p=0.0001 and p=0.0042), but bitterness intensity was mostly determined by TAS2R38 genotypes (p<0.000001). Fungiform papillae densities were associated with both genotypes (p<0.014) (with a stronger effect for gustin; p=0.0006), but papilla morphology was a function of gustin alone (p<0.0012). Treatment of isolated cells with saliva from individuals with the AA form of gustin or direct application of the active iso-form of gustin protein increased cell proliferation and metabolic activity (p<0.0135). These novel findings suggest that the rs2274333 polymorphism of the gustin gene affects PROP sensitivity by acting on fungiform papilla development and maintenance, and could provide the first mechanistic explanation for why PROP super-tasters are more responsive to a broad range of oral stimul
Hereditary ovarian cancer
Apoptosis is a form of cell death that permits the removal of damaged, senescent or unwanted cells in
multicellular organisms, without damage to the cellular microenvironment. Defective apoptosis represents
a major causative factor in the development and progression of cancer. The majority of chemotherapeutic
agents, as well as radiation, utilize the apoptotic pathway to induce cancer cell death. Resistance to standard
chemotherapeutic strategies also seems to be due to alterations in the apoptotic pathway of cancer cells.
Recent knowledge on apoptosis has provided the basis for novel targeted therapies that exploit apoptosis to
treat cancer. These new target include those acting in the extrinsic/intrinsic pathway, proteins that control the
apoptosis machinery such as the p53 and proteosome pathway. Most of these forms of therapy are still in
preclinical development because of their low specifity and susceptibility to drug resistance, but several of them
have shown promising results. In particular, this review specifically aims at providing an update of certain
molecular players that are already in use in order to target apoptosis (such as bortezomib) or which are still being
clinically evaluated (such ONYX-015, survivin and exisulind/aptosyn) or which, following preclinical studies,
might have the necessary requirements for becoming part of the anticancer drug programs (such as TRAIL/
Apo2L, apoptin/VP3).
Key words: apoptosis, TRAIL/Apo2L, apoptin/VP3, ONYX015, Bortezomib, exisulind, survivi
The Clinical Significance of Unknown Sequence Variants in BRCA Genes
Abstract: Germline mutations in BRCA1/2 genes are responsible for a large proportion of hereditary breast and/or ovarian cancers. Many highly penetrant predisposition alleles have been identified and include frameshift or nonsense mutations that lead to the translation of a truncated protein. Other alleles contain missense mutations, which result in amino acid substitution and intronic variants with splicing effect. The discovery of variants of uncertain/unclassified significance (VUS) is a result that can complicate rather than improve the risk assessment process. VUSs are mainly missense mutations, but also include a number of intronic variants and in-frame deletions and insertions. Over 2,000 unique BRCA1 and BRCA2 missense variants have been identified, located throughout the whole gene (Breast Cancer Information Core Database (BIC database)). Up to 10–20% of the BRCA tests report the identification of a variant of uncertain significance. There are many methods to discriminate deleterious/high-risk from neutral/low-risk unclassified variants (i.e., analysis of the cosegregation in families of the VUS, measure of the influence of the VUSs on the wild-type protein activity, comparison of sequence conservation across multiple species), but only an integrated analysis of these methods can contribute to a real interpretation of the functional and clinical role of the discussed variants. The aim of our manuscript is to review the studies on BRCA VUS in order to clarify their clinical relevance
A Practical Approach for Wall Shear Stress Topological Skeleton Analysis Applied to Intracranial Aneurysm Hemodynamics
The physiopathological role of Wall Shear Stress (WSS) in intracranial aneurysm development/rupture and the action of contraction/expansion played by shear forces on vessel wall make topological skeleton analysis of the WSS vector field of great interest. Here we present a practical way to analyze WSS topological skeleton through the identification and classification of WSS fixed points and manifolds. The method is based on the calculation of the WSS vector field divergence and Poincarè index, and it is here successfully applied to a dataset computational hemodynamic models of intracranial aneurysms
Influence of the MCT1 rs1049434 on Indirect Muscle Disorders/Injuries in Elite Football Players
The aim of this study was to investigate the association between MCT1 rs1049434 polymorphism and indirect muscle injuries in elite football players. One hundred and seventy-three male elite Italian football players (age = 19.2 ± 5.3 years) were recruited from a first-league football club participating at the Official National Italian Football Championship (Serie A, Primavera, Allievi, Giovanissimi). The cohort was genotyped for the MCT1 rs1049434 polymorphism, and muscle injuries data were collected during the period of 2009-2014 (five football seasons).Genomic DNA was extracted using a buccal swab, and genotyping was performed using PCR method. Structural-mechanical injuries and functional muscle disorder were included in the acute indirect muscle injury group.Participants with the MCT1 AA (AA = 1.57 ± 3.07, n = 69) genotype exhibit significantly higher injury incidents compared to participants with the TT genotype (TT = 0.09 ± 0.25, n = 22, P = 0.04).The MCT1 rs1049434 polymorphism is associated with the incidence of muscle injuries in elite football players. We anticipate that the knowledge of athletes' genetic predisposition to sports-related injuries might aid in individualizing training programs
Deciphering ascending thoracic aortic aneurysm hemodynamics in relation to biomechanical properties
The degeneration of the arterial wall at the basis of the ascending thoracic aortic aneurysm (ATAA) is a complex multifactorial process, which may lead to clinical complications and, ultimately, death. Individual genetic, biological or hemodynamic factors are inadequate to explain the heterogeneity of ATAA development/progression mechanisms, thus stimulating the analysis of their complex interplay. Here the disruption of the hemodynamic environment in the ATAA is investigated integrating patient-specific computational hemodynamics, CT-based in vivo estimation of local aortic stiffness and advanced fluid mechanics methods of analysis. The final aims are (1) deciphering the ATAA spatiotemporal hemodynamic complexity and its link to near-wall topological features, and (2) identifying the existing links between arterial wall degeneration and hemodynamic insult. Technically, two methodologies are applied to computational hemodynamics data, the wall shear stress (WSS) topological skeleton analysis, and the Complex Networks theory. The same analysis was extended to the healthy aorta. As main findings of the study, we report that: (1) different spatiotemporal heterogeneity characterizes the ATAA and healthy hemodynamics, that markedly reflect on their WSS topological skeleton features; (2) a link (stronger than canonical WSS-based descriptors) emerges between the variation of contraction/expansion action exerted by WSS on the endothelium along the cardiac cycle, and ATAA wall stiffness. The findings of the study suggest the use of advanced methods for a deeper understanding of the hemodynamics disruption in ATAA, and candidate WSS topological skeleton features as promising indicators of local wall degeneration
Is BRCA1-5083del19, identified in breast cancer patients of Sicilian origin, a Calabrian founder mutation?
Various studies have been published in Italy regarding the different BRCA1 mutations, but only the BRCA1-5083del19 mutation is recurrent and specific to individuals of Italian descent with a founder effect on the Calabrian population. In our previous study, BRCA1-5083del19 mutation carriers were found in four index cases of 106 Sicilian patients selected for familial and/or hereditary breast/ovarian cancers. The high frequency rate of this mutation identified in the Sicilian population led us to perform haplotype analysis in all family carriers. Five highly polymorphic microsatellite markers were used (D17S1320, D17S932, D17S1323, D17S1326, D17S1325) to establish whether or not all these families had a common ancestor. This analysis showed that all mutation carriers of these families had a common allele. None of the non-carriers of the mutation or of the 50 healthy Sicilian controls showed this haplotype. This allelotype analysis highlighted the presence of a common allele (ancestor), thus suggesting the presence of a founder effect in the Sicilian population. Our results are in contrast with other studies but only the allelotype analysis of all the BRCA1-5083del19 mutation carriers of two neighboring regions of the south of Italy (Calabria and Sicily) will make it possible to identify the real ancestor of this mutation
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