University of Siena

About: University of Siena is a education organization based out in Siena, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 12179 authors who have published 33334 publications receiving 1008287 citations. The organization is also known as: Università degli studi di Siena & Universita degli studi di Siena.

Efficacy of periodontal plastic surgery procedures in the treatment of localized facial gingival recessions. A systematic review.

Abstract: Background The aim of this Systematic Review (SR) was to assess the clinical efficacy of periodontal plastic surgery procedures in the treatment of localized gingival recessions (Rec) with or without inter-dental clinical attachment loss (iCAL). Material and Methods Electronic and hand searches were performed to identify randomized clinical trials (RCTs) on treatment of single gingival recessions with at least 6 months of follow-up. Primary outcome variable was complete root coverage (CRC). Secondary outcome variables were recession reduction (RecRed) and keratinized tissue (KT) gain. To evaluate treatment effect, Odds Ratios were combined for dichotomous data and mean differences in continuous data using a random-effect model. Results Fifty-one RCTs (53 articles) with a total of 1574 treated patients (1744 recessions) were included in this SR. Finally, 30 groups of comparisons were identified and a total of 80 meta-analyses were performed. Coronally Advanced Flap (CAF) was associated with higher probability of CRC and higher amount of RecRed than Semilunar Coronal Positioned Flap (SCPF). The combination CAF plus Connective Tissue Graft (CAF+CTG) or CAF plus Enamel Matrix Derivative (CAF+EMD) was more effective than CAF alone in terms of CRC and RecRed. The combination CAF plus Collagen Matrix (CAF+CM) achieved higher RecRed than CAF alone. In addition, CAF+CTG achieved CRC more frequently than CAF+EMD, SCPF, Free Gingival Graft (FGG) and Laterally Positioned Flap (LPS). CAF+CTG was also associated with higher RecRed than Barrier Membranes (CAF+GTR), CAF+EMD and CAF+CM. GTR was not able to improve the clinical efficacy of CAF. Studies adding Acellular Dermal Matrix (ADM) under CAF showed a large heterogeneity and not significant benefits compared with CAF alone. Multiple combinations, using more than a single graft/biomaterial under the flap, usually provide similar or less benefits than simpler, control procedures in term of root coverage outcomes. Conclusions CAF procedures alone or with CTG, EMD are supported by large evidence in modern periodontal plastic surgery. CAF+CTG achieved the best clinical outcomes in single gingival recessions with or without iCAL.

Protein and mRNA expression of autophagy gene Beclin 1 in human brain tumours.

Abstract: Beclin 1 is is an autophagy gene, the role of which as a tumour suppressor has recently been recognized in a few studies. We examined the expression of Beclin 1 protein in 212 primary human brain tumours, including 97 high-grade glial tumours, 29 low-grade glial tumours, 4 grade III meningiomas, 19 grade II meningiomas, 52 grade I meningiomas, and 11 medulloblastomas. In 94 cases, including 56 glial tumours, 35 meningiomas, and 3 medulloblastomas we also assessed Beclin 1 mRNA expression by real-time RT-PCR. In most high-grade astrocytic, ependymal neoplasms and atypical meningiomas we found a decrease of cytoplasmic protein expression that was, instead, high in the majority of low-grade tumours and in medulloblastomas. The expression level of Beclin 1 mRNA was significantly lower in glioblastomas than in grade II (p=0.04) and grade I (p=0.01) astrocytomas; in grade III than in grade I astrocytomas (p=0.01); in grade II than in grade I meningiomas (p=0.03); and in all glial tumours when compared to all meningiomas (p<0.0001). Cytoplasmic expression is thought to be linked to the functional protein. Our observations are in line with studies that demonstrated decreased expression of Beclin 1 in human breast, ovarian, prostate and ovarian cancer and furtherly support its involvement also in brain tumours, which had previously been demonstrated in a few experimental studies, both in spontaneous and in therapy-induced autophagy. Furthermore, our study suggests possible differences of Beclin 1 involvement and its role among the different histotypes of brain neoplasms. Further studies are needed to highlight Beclin 1 function in tumour suppression and/or in tumour survival through autophagy and other related programmed cell death processes in brain tumours.

Cryptic deletions are a common finding in “balanced” reciprocal and complex chromosome rearrangements: a study of 59 patients

Abstract: Using array comparative genome hybridisation (CGH) 41 de novo reciprocal translocations and 18 de novo complex chromosome rearrangements (CCRs) were screened. All cases had been interpreted as "balanced" by conventional cytogenetics. In all, 27 cases of reciprocal translocations were detected in patients with an abnormal phenotype, and after array CGH analysis, 11 were found to be unbalanced. Thus 40% (11 of 27) of patients with a "chromosomal phenotype" and an apparently balanced translocation were in fact unbalanced, and 18% (5 of 27) of the reciprocal translocations were instead complex rearrangements with >3 breakpoints. Fourteen fetuses with de novo, apparently balanced translocations, all but two with normal ultrasound findings, were also analysed and all were found to be normal using array CGH. Thirteen CCRs were detected in patients with abnormal phenotypes, two in women who had experienced repeated spontaneous abortions and three in fetuses. Sixteen patients were found to have unbalanced mutations, with up to 4 deletions. These results suggest that genome-wide array CGH may be advisable in all carriers of "balanced" CCRs. The parental origin of the deletions was investigated in 5 reciprocal translocations and 11 CCRs; all were found to be paternal. Using customized platforms in seven cases of CCRs, the deletion breakpoints were narrowed down to regions of a few hundred base pairs in length. No susceptibility motifs were associated with the imbalances. These results show that the phenotypic abnormalities of apparently balanced de novo CCRs are mainly due to cryptic deletions and that spermatogenesis is more prone to generate multiple chaotic chromosome imbalances and reciprocal translocations than oogenesis.

Target or barrier? The cell wall of early- and later-diverging plants vs cadmium toxicity: differences in the response mechanisms

Abstract: Increasing industrialization and urbanization result in emission of pollutants in the environment including toxic heavy metals, as cadmium and lead. Among the different heavy metals contaminating the environment, cadmium raises great concern, as it is ecotoxic and as such can heavily impact ecosystems. The cell wall is the first structure of plant cells to come in contact with heavy metals. Its composition, characterized by proteins, polysaccharides and in some instances lignin and other phenolic compounds, confers the ability to bind non-covalently and/or covalently heavy metals via functional groups. A strong body of evidence in the literature has shown the role of the cell wall in heavy metal response: it sequesters heavy metals, but at the same time its synthesis and composition can be severely affected. The present review analyzes the dual property of plant cell walls, i.e., barrier and target of heavy metals, by taking Cd toxicity as example. Following a summary of the known physiological and biochemical responses of plants to Cd, the review compares the wall-related mechanisms in early- and later-diverging land plants, by considering the diversity in cell wall composition. By doing so, common as well as unique response mechanisms to metal/cadmium toxicity are identified among plant phyla and discussed. After discussing the role of hyperaccumulators’ cell walls as a particular case, the review concludes by considering important aspects for plant engineering.