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Background: Colon cancer in young patients is often associated with hereditary syndromes; however, in early-onset rectal cancer, mutations of these genes are rarely observed. The aim of this study was to analyse the features of the local immune microenvironment and the mutational pattern in early-onset rectal cancer. Methods: Commonly mutated genes were analysed within a rectal cancer series from the University Hospital of Padova. Mutation frequency and immune gene expression in a cohort from The Cancer Genome Atlas ('TCGA') were compared and immune-cell infiltration levels in the healthy rectal mucosa adjacent to rectal cancers were evaluated in the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 ('IMMUNOREACT') series. Results: In the authors' series, the mutation frequency of BRAF, KRAS, and NRAS, as well as microsatellite instability frequency, were not different between early- and late-onset rectal cancer. In The Cancer Genome Atlas series, among the genes with the most considerable difference in mutation frequency between young and older patients, seven genes are involved in the immune response and CD69, CD3, and CD8β expression was lower in early-onset rectal cancer. In the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 series, young patients had a lower rate of CD4+ T cells, but higher T regulator infiltration in the rectal mucosa. Conclusion: Early-onset rectal cancer is rarely associated with common hereditary syndromes. The tumour microenvironment is characterized by a high frequency of mutations impairing the local immune surveillance mechanisms and low expression of immune editing-related genes. A constitutively low number of CD4 T cells associated with a high number of T regulators indicates an imbalance in the immune surveillance mechanisms. [ABSTRACT FROM AUTHOR]

Masonry arch bridges are typically historical infrastructures that were often not designed to withstand the heavy truck traffic that they are currently carrying and therefore must be replaced by modern concrete or steel bridges. Usual methods of strengthening masonry bridges are neither simple nor economical. This paper investigates whether the application of composites in the form of either a fabric wrap or laminate strips to masonry constructions may increase the load-bearing capacity of these structures. This research project demonstrates how advanced composite materials can be used to strengthen existing masonry arch bridges in order to increase their load-bearing capacity. This paper details the methodology adopted to retrofit and repair the Castagnara masonry bridge in Padua (Italy) and the investigations related to the damage of the bridge, the retrofitting by fibre reinforced plastic (FRP) elements and the results of the consolidation. Retrofitting involves the insertion of a prestressed steel cable into the abutments, consolidating injections, bonding by FRP strips on the extrados of the deck and demolition and reconstruction of the reinforced concrete slab. Linear-elastic and non-linear dynamic analysis of the bridge have been performed. Detailed finite element models (FEM) and on-site dynamic acceleration measurements were used to evaluate retrofit performance. Results show that applying carbon fabric to the masonry bridges provides significant increases in bending and shear capacity. However, a statistically significant number of masonry structures strengthened with carbon fibres need to be tested to arrive at definitive stress modification factors. [ABSTRACT FROM AUTHOR]