cag Pathogenicity island-dependent upregulation of matrix metalloproteinase-7 in infected patients with Helicobacter pylori.

Helicobacter pylori (H. pylori) infection has been involved in the pathogenesis of most important gastroduodenal diseases. Matrix metalloproteinases (MMPs) are a large family of zincendopeptidases which play important roles in degradation of extracellular matrix (ECM) and various inflammatory diseases. Therefore, we examined MMP-7 mRNA levels in the gastric mucosa of patients with H. pylori infection and evaluated the effects of virulence factors, such as vacA (vacuolating cytotoxin A) and cagA (cytotoxin-associated gene), in H. pylori-infected patients upon the MMP-7 mRNA mucosal levels. We also determined the correlation between mucosal MMP-7 mRNA levels and the types of disease. Total RNA was extracted from gastric biopsies of 50 H. pylori-infected patients and 50 uninfected individuals. Mucosal MMP-7 mRNA expression level in H. pylori-infected and non-infected gastric biopsies was determined by real-time polymerase chain reaction (PCR). The presences of cagA and vacA virulence factors was evaluated using PCR. MMP-7 expression was significantly higher in biopsies of patients infected with H .pylori compared to uninfected individuals. In addition, mucosal MMP-7 mRNA expression in H. pylori-infected patients significantly associated with the cagA status and the types of disease. Our results suggest that MMP-7 might be involved in the pathogenesis of H. pylori. Peptic ulcer was associated with cag pathogenicity island-dependent MMP-7 upregulation.

Anticorrosion and Antimicrobial Tannic Acid-Functionalized Ti-Metallic Glass Ribbons for Dental Abutment.

In this study, a recently reported Ti-based metallic glass (MG), without any toxic element, but with a significant amount of metalloid (Si-Ge-B, 18 atom %) and minor soft element (Sn, 2 atom %), was produced in ribbon form using conventional single-roller melt-spinning. The produced Ti60Zr20Si8Ge7B3Sn2 ribbons were investigated by differential scanning calorimetry and X-ray diffraction to confirm their amorphous structure, and their corrosion properties were further investigated by open-circuit potential and cyclic polarization tests. The ribbon's surface was functionalized by tannic acid, a natural plant-based polyphenol, to enhance its performance in terms of corrosion prevention and antimicrobial efficacy. These properties can potentially be exploited in the premucosal parts of dental implants (abutments). The Folin and Ciocalteu test was used for the quantification of tannic acid (TA) grafted on the ribbon surface and of its redox activity. Fluorescent microscopy and ζ-potential measurements were used to confirm the presence of TA on the surfaces of the ribbons. The cytocompatibility evaluation (indirect and direct) of TA-functionalized Ti60Zr20Si8Ge7B3Sn2 MG ribbons toward primary human gingival fibroblast demonstrated that no significant differences in cell viability were detected between the functionalized and as-produced (control) MG ribbons. Finally, the antibacterial investigation of TA-functionalized samples against Staphylococcus aureus demonstrated the specimens' antimicrobial properties, shown by scanning electron microscopy images after 24 h, presenting a few single colonies remaining on their surfaces. The thickness of bacterial aggregations (biofilm-like) that were formed on the surface of the as-produced samples reduced from 3.5 to 1.5 µm.

Multi-Directional Universal Energy Harvesting Ball.

This paper discusses the development of a multi-directional, universal, electromagnetic energy harvester. The device is a ball consisting of two parts: a rigid spherical core with internal tubes, coils and magnets, and a flexible silicone-based shell holding a carrier fluid. The multi-directional aspect of the design comes from the device's spherical shape. The harvester generates energy when subject to compressive force, by moving fluid through a tube, pushing a permanently magnetized ball through a coil wound around the tube. A combination of 3-D printed PLA plastic and molded silicone was used to produce a prototype. The energy harvester can be utilized in applications where there is an oscillating compression and it is not limited to certain applications due to its universal ball shape. It was tested at five different frequencies between 4-15 Hz on its four different outer sides producing electricity at a range of 17 to 44 mV.