Chemical Characterisation of Silanised Zirconia Nanoparticles and Their Effects on the Properties of PMMA-Zirconia Nanocomposites
AuthorsZidan, Saleh; email: email@example.com
Silikas, Nikolaos; orcid: 0000-0003-4576-4584; email: firstname.lastname@example.org
Al-Nasrawi, Suhad; orcid: 0000-0003-3045-7389; email: email@example.com
Haider, Julfikar; orcid: 0000-0001-7010-8285; email: firstname.lastname@example.org
Alshabib, Abdulrahman; email: Abdalshabib@ksu.edu.sa
Alshame, Alshame; email: Als.email@example.com
Yates, Julian; email: firstname.lastname@example.org
MetadataShow full item record
AbstractObjectives: The objective of this study was to investigate the mechanical properties of high-impact (HI) heat-cured acrylic resin (PMMA) reinforced with silane-treated zirconia nanoparticles. Methods: Forty-five PMMA specimens reinforced with zirconia were fabricated and divided into three groups: Pure HI PMMA (control group), PMMA reinforced with 3 wt.% of non-silanised zirconia nanoparticles and PMMA reinforced with 3 wt.% of silanised zirconia nanoparticles. Silanised and non-silanised zirconia nanoparticles were analysed with Fourier Transform Infrared (FTIR) Spectroscopy. For measuring the flexural modulus and strength, a Zwick universal tester was used, and for surface hardness, a Vickers hardness tester were used. Furthermore, raw materials and fractured surfaces were analysed using Scanning Electron Microscopy (SEM). A one-way ANOVA test followed by a post-hoc Bonferroni test was employed to analyse the data. Results: The results showed that the mean values for flexural strength (83.5 ± 6.2 MPa) and surface hardness (20.1 ± 2.3 kg/mm2) of the group containing 3 wt.% treated zirconia increased significantly (p 0.05) in comparison to the specimens in the group containing non-treated zirconia (59.9 ± 7.1 MPa; 15.0 ± 0.2 kg/mm2) and the control group (72.4 ± 8.6 MPa; 17.1 ± 0.9 kg/mm2). However, the group with silanised zirconia showed an increase in flexural modulus (2313 ± 161 MPa) but was not significantly different (p > 0.05) from the non-silanised group (2207 ± 252 MPa) and the control group (1971 ± 235 MPa). Conclusion: Silane-treated zirconia nano-filler improves the surface hardness and flexural strength of HI PMMA-zirconia nanocomposites, giving a potentially longer service life of the denture base.
CitationMaterials, volume 14, issue 12, page e3212
DescriptionFrom MDPI via Jisc Publications Router
History: accepted 2021-06-08, pub-electronic 2021-06-10
Publication status: Published
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Gene-Environment Interactions Relevant to Estrogen and Risk of Breast Cancer: Can Gene-Environment Interactions Be Detected Only among Candidate SNPs from Genome-Wide Association Studies?Park, JooYong; email: email@example.com; Choi, Ji-Yeob; email: firstname.lastname@example.org; Choi, Jaesung; email: email@example.com; Chung, Seokang; email: firstname.lastname@example.org; Song, Nan; orcid: 0000-0002-9182-1060; email: email@example.com; Park, Sue K.; orcid: 0000-0001-5002-9707; email: firstname.lastname@example.org; Han, Wonshik; email: email@example.com; Noh, Dong-Young; email: firstname.lastname@example.org; Ahn, Sei-Hyun; email: email@example.com; Lee, Jong Won; email: firstname.lastname@example.org; et al. (MDPI, 2021-05-14)In this study we aim to examine gene–environment interactions (GxEs) between genes involved with estrogen metabolism and environmental factors related to estrogen exposure. GxE analyses were conducted with 1970 Korean breast cancer cases and 2052 controls in the case-control study, the Seoul Breast Cancer Study (SEBCS). A total of 11,555 SNPs from the 137 candidate genes were included in the GxE analyses with eight established environmental factors. A replication test was conducted by using an independent population from the Breast Cancer Association Consortium (BCAC), with 62,485 Europeans and 9047 Asians. The GxE tests were performed by using two-step methods in GxEScan software. Two interactions were found in the SEBCS. The first interaction was shown between rs13035764 of NCOA1 and age at menarche in the GE|2df model (p-2df = 1.2 × 10−3). The age at menarche before 14 years old was associated with the high risk of breast cancer, and the risk was higher when subjects had homozygous minor allele G. The second GxE was shown between rs851998 near ESR1 and height in the GE|2df model (p-2df = 1.1 × 10−4). Height taller than 160 cm was associated with a high risk of breast cancer, and the risk increased when the minor allele was added. The findings were not replicated in the BCAC. These results would suggest specificity in Koreans for breast cancer risk.
No Difference in Penetrance between Truncating and Missense/Aberrant Splicing Pathogenic Variants in MLH1 and MSH2: A Prospective Lynch Syndrome Database StudyDominguez-Valentin, Mev; orcid: 0000-0001-7856-0057; email: Mev.Dominguez.Valentin@rr-research.no; Plazzer, John-Paul; orcid: 0000-0001-5114-4301; email: email@example.com; Sampson, Julian R.; email: Sampson@cardiff.ac.uk; Engel, Christoph; orcid: 0000-0002-7247-282X; email: firstname.lastname@example.org; Aretz, Stefan; orcid: 0000-0002-5228-1890; email: email@example.com; Jenkins, Mark A.; email: firstname.lastname@example.org; Sunde, Lone; email: email@example.com; Bernstein, Inge; email: firstname.lastname@example.org; Capella, Gabriel; orcid: 0000-0002-4669-7320; email: email@example.com; Balaguer, Francesc; orcid: 0000-0002-0206-0539; email: firstname.lastname@example.org; et al. (MDPI, 2021-06-28)Background. Lynch syndrome is the most common genetic predisposition for hereditary cancer. Carriers of pathogenic changes in mismatch repair (MMR) genes have an increased risk of developing colorectal (CRC), endometrial, ovarian, urinary tract, prostate, and other cancers, depending on which gene is malfunctioning. In Lynch syndrome, differences in cancer incidence (penetrance) according to the gene involved have led to the stratification of cancer surveillance. By contrast, any differences in penetrance determined by the type of pathogenic variant remain unknown. Objective. To determine cumulative incidences of cancer in carriers of truncating and missense or aberrant splicing pathogenic variants of the MLH1 and MSH2 genes. Methods. Carriers of pathogenic variants of MLH1 (path_MLH1) and MSH2 (path_MSH2) genes filed in the Prospective Lynch Syndrome Database (PLSD) were categorized as truncating or missense/aberrant splicing according to the InSiGHT criteria for pathogenicity. Results. Among 5199 carriers, 1045 had missense or aberrant splicing variants, and 3930 had truncating variants. Prospective observation years for the two groups were 8205 and 34,141 years, respectively, after which there were no significant differences in incidences for cancer overall or for colorectal cancer or endometrial cancers separately. Conclusion. Truncating and missense or aberrant splicing pathogenic variants were associated with similar average cumulative incidences of cancer in carriers of path MLH1 and path_MSH2.
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