Burden of upper gastrointestinal cancers in the east of Golestan province (Golestan cohort study).

BACKGROUND: Cancers, especially Upper Gastrointestinal Cancers (UGCs), pose a substantial burden on society, particularly in developing nations. Golestan province, Iran, is known for its high UGC rates globally. AIMS: This study delves into the disease burden of UGCs in the eastern part of Golestan province. METHODS AND RESULTS: This study was conducted using the results of the Golestan cohort study. 2711 patients participating in this cohort, who visited Atrak Clinic during 2001-2020, participated in this study. After excluding patients with incomplete records, 2481 patients were included in the study. To compute the metrics of years of life lost (YLL), years of life lived with disability (YLD), and disability-adjusted life years (DALY), we utilized the World Health Organization's standard life table, stratified by age and gender. The majority of UGC patients in our study were married (81.8%), had limited formal education (82.6%), and were predominantly male (61.1%). A substantial proportion resided in suburban areas (85.8%), and over half of the patients (52%) reported a history of drug addiction. The mean age at diagnosis for men was 65.76 years with a standard deviation of 11.34, while for women, it was 64.38 years with a standard deviation of 11.66. Regarding disease impact, YLL, YLD, and DALY for men were 21 240, 1956, and 23 196 (307.8 per 100 000), respectively. For women, these figures were 15 609 for YLL, 1367 for YLD, and 16 976 (223.1 per 100 000) for DALY. CONCLUSION: After the increasing trend of the burden of UGCs in Golestan province in the early years of the study, this rate has been decreasing in recent years. Effective strategies necessitate collaborative efforts across various sectors to alleviate this burden, focusing on preventive measures, timely diagnosis, and well-coordinated therapeutic interventions.

Inorganic Bottlebrush and Comb Polymers as a Platform for Supersoft, Solvent-Free Elastomers.

Due to their unique rheological and mechanical properties, bottlebrush polymers are inimitable components of biological and synthetic systems such as cartilage and ultrasoft elastomers. However, while their rheological properties can be precisely controlled through their macromolecular structures, the current chemical spectrum available is limited to a handful of synthetic polymers with aliphatic carbon backbones. Herein we design and synthesize a series of inorganic bottlebrush polymers based on a unique combination of polydimethylsiloxane (PDMS) and polyphosphazene (PPz) chemistry. This non-carbon-based platform allows for simple variation of the significant architectural dimensions of bottlebrush-polymer-based elastomers. Grafting PDMS to PPz and vice versa also allows us to further exploit the unique properties of these polymers combined in a single material. These novel hybrid bottlebrush polymers were cured to give supersoft, solvent-free elastomers. We systematically studied the effect of architectural parameters and chemical functionality on their rheological properties. Besides forming supersoft elastomers, the energy dissipation characteristics of the elastomers were observed to be considerably higher than those for PDMS-based elastomers. Hence this work introduces a robust synthetic platform for solvent-free supersoft elastomers with potential applications as biomimetic damping materials.

Cytotoxicity Comparison of a Calcium Silicate-Based Resin Cement versus Conventional Self-Adhesive Resin Cement and a Resin-Modified Glass Ionomer: Cell Viability Analysis

Abstract Objective: To compare the cytotoxicity level of a new calcium silicate-based resin cement (TheraCem) with two commonly used cements, including a conventional self-adhesive resin cement (Panavia SA) and a resinmodified glass ionomer cement (FujiCem2), on the human gingival fibroblast cells after 24 and 48 hours. Material and Methods: Twelve discs of each cement type were fabricated. The extract of cement disks was made by incubating them in the cell medium. Human gingival fibroblast cells were cultured and exposed to cement extracts for 24 h and 48 h. MTT assay was performed on extracts and optical density and cell viability rates were calculated by the spectrophotometer device at 570 nm. Data were analyzed using ANOVA and Tukey HSD tests. Results: The cell viability rates after 24 hours and 48 hours were as follows: TheraCem: 89.24% and 85.46%, Panavia SA: 49.51% and 46.57% and FujiCem2: 50.63% and 47.36%. TheraCem represented the highest cell viability rate. However, no significant difference was noted between Panavia SA and FujiCem2. Time had no significant effect on cell viability. Conclusion: TheraCem exhibited the best results among three tested cements and was considered non-toxic. Panavia SA and FujiCem2 were not significantly different regarding the cell viability rate. Time had no significant effect on the cytotoxicity level of cements (AU).

Interfacial Fracture Toughness Comparison of Three Indirect Resin Composites to Dentin and Polyether Ether Ketone Polymer.

OBJECTIVES: Advances in laboratory composites and their high wear resistance and fracture toughness have resulted in their growing popularity and increasing use for dental restorations. This study sought to assess the fracture toughness of three indirect composites bonded to dental substrate and polyether ether ketone (PEEK) polymer. MATERIALS AND METHODS: This in vitro study was conducted on two groups of dental and polymer substrates. Each substrate was bonded to three indirect composite resins. Sixty blocks (3 × 3 × 12 mm) were made of sound bovine anterior teeth and PEEK polymer. Sixty blocks (3 × 3 × 12 mm) were fabricated of CRIOS (Coltene, Germany), high impact polymer composite (HIPC; Bredent, Germany), and GRADIA (Indirect; GC, Japan) composite resins. Composites were bonded to dentin using Panavia F 2.0 (Kuraray, Japan). For bonding to PEEK, Combo.lign (Bredent) and Visio.Link (Bredent) luting cements were used. In all samples, a single-edge notch was created by a no. 11 surgical blade at the interface. The samples were subjected to 3,500 thermal cycles, and their fracture toughness was measured in a universal testing machine (Zwick/Roell, Germany) by application of four-point flexural load. STATISTICAL ANALYSIS: Data were analyzed using one-way analysis of variance, Kruskal-Wallis. RESULTS: The fracture toughness of CRIOS-PEEK interface was significantly higher than HIPC-PEEK. The fracture toughness of GRADIA-PEEK was not significantly different from that of HIPC and CRIOS. The fracture toughness of GRADIA-dentin was significantly higher than HIPC-dentin. CONCLUSION: Considering the limitations of this study, GRADIA has the highest bond strength to dentin, while CRIOS shows the highest bond strength to PEEK.

Degree of conversion and water sorption of self-adhesive and conventional flowable composites: an in vitro study

Aim: Self-adhesive flowable composite resins have been recently introduced to the market. Degree of conversion (DC) and water sorption (WS) are two important parameters affecting the properties of restorative materials. This study aimed to assess the DC and WS of a self-adhesive flowable composite resin in comparison with two conventional flowable composite resins. Methods: Vertise Flow (VF) self-adhesive and Tetric-N Flow (TF) and Grandio Flow (GF) conventional flowable composites were evaluated in this in vitro, experimental study. The DC (n=3) was determined by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The WS (n=7) was measured after 7 days of immersion in artificial saliva accordingto ISO 4049specifications. Data were analyzed by one-way ANOVA and a post-hoc test (p<0.05). Results: VF showed the highest DC percentage (84.3%) followed by GF (72.79%) and TF (68.7%). The latter two had no significant difference (p=0.8). WS was the highest in VF (55.2 µg/mm3), and the two conventional flowable composites had a significant difference in WS (19.5 µg/mm3 in TF and 11 µg/mm3 in GF; p<0.001). Conclusions: Flowable composite resins had significant differences in DC and WS, and VF demonstrated the highest DC and WS