Recently an increasing number of new adenovirus types associated with type-dependent pathogenicity have been identified. However, identification of these clinical isolates represents the very first step to characterize novel pathogens. For deeper analyses, these adenoviruses need to be further characterized in basic virology experiments or they could be applied in translational research. To achieve this goal, it is essential to get genetic access and to enable genetic modification of these novel adenovirus genomes (deletion, insertion, and mutation). Here we demonstrate a high-throughput approach to get genetic access to new adenoviruses via homologous recombination. We first defined the cloning conditions regarding homology arm-length and input adenoviral genome amounts. Then we cloned four naturally occurring adenoviruses (Ad70, Ad73, Ad74, and Ad75) into easy-to-manipulate plasmids and genetically modified them by reporter gene insertion. Three recombinant adenoviruses (Ad70, Ad73, and Ad74) containing a reporter cassette were successfully reconstituted. These novel reporter-labeled adenoviruses were further characterized using the inserted luciferase reporter with respect to receptor usage, presence of anti-adenovirus antibodies, and tropism in vitro. The identified receptor usage, the relatively low prevalence of anti-adenovirus antibodies, and the various cancer cell line transduction pattern are important features of these new pathogens providing essential information for their therapeutic application.
Chipping of veneering is the most common clinical complication for zirconia restorations. Veneering composite could be a promising alternative to renew restorations. Zirconia discs (3-YSZ) were prepared with varying surface treatments and bonded to indirect composite as follows: air abrasion and Scotchbond Universal (A/SU); air abrasion and Clearfil Ceramic Primer (A/C); air abrasion and MKZ Primer (A/M); air abrasion and Monobond Plus (A/MP); silica-coating and Scotchbond Universal (S/SU); air abrasion (AP/SU), additional cold atmospheric plasma treatment, and Scotchbond Universal. An indirect composite material was then applied to the zirconia specimens. Specimens were divided into subgroups for short-term (14 days storage at 37 °C and 5000 thermal cycles) and long-term (250 days storage and 37,500 thermal cycles) artificial aging. Shear bond strength measurement (SBS) was performed, and data were analyzed by Kruskal–Wallis-test and multiple comparison testing with Dunn’s correction (p ≤ 0.05). The median SBS values (MPa) of short- and long-term artificial aging were: 3.09/1.36 (A/SU); 0.77/1.43 (S/SU); 2.82/2.15 (AP/SU); 1.97/1.80 (A/C); 2.01/1.58 (A/M); and 1.70/1.68 (A/MP). For short-term artificial aging A/SU showed the highest median SBS values, whereas in the long-term trial, AP/SU showed the highest values and the difference was significant. A prolonged artificial aging decreased SBS in all groups, except S/SU. In summary, treatment with CAP can improve SBS in the long-term.
Applying antibacterial coatings to dental implant materials seems reasonable but can have negative influences on desired cell adhesion and healing. In this study, zirconia abutment specimens interacting with gingival tissue were used. The aim was to compare the influence of machined or coated zirconia surfaces on the adhesion and proliferation of human gingival fibroblasts (HGF-1). Surface modifications were performed using atmospheric plasma coating with hydroxyapatite, zinc, and copper. Zirconia specimens were divided into four groups: hydroxyapatite, hydroxyapatite with zinc oxide (ZnO), hydroxyapatite with copper (Cu), and an untreated machined surface. After the characterization of the surface conditions, the morphology of adhered HGF-1 was determined by fluorescence staining and subjected to statistical evaluation. The visual analysis of cell morphology by SEM showed flat, polygonal, and largely adherent fibroblast cells in the untreated group, while round to partially flat cells were recorded in the groups with hydroxyapatite, hydroxyapatite + ZnO, and hydroxyapatite + Cu. The cell membranes in the hydroxyapatite + ZnO and hydroxyapatite + Cu groups appeared porous. The results show that HGF-1 adhere and proliferate well on machined zirconia, while plasma coating with hydroxyapatite or hydroxyapatite mixtures does not lead to increased adhesion or proliferation.
Previous studies reported on the broad-spectrum antiviral function of heparin. Here we investigated the antiviral function of magnesium-modified heparin and found that modified heparin displayed a significantly enhanced antiviral function against human adenovirus (HAdV) in immortalized and primary cells. Nuclear magnetic resonance analyses revealed a conformational change of heparin when complexed with magnesium. To broadly explore this discovery, we tested the antiviral function of modified heparin against herpes simplex virus type 1 (HSV-1) and found that the replication of HSV-1 was even further decreased compared to aciclovir. Moreover, we investigated the antiviral effect against the new severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and measured a 55-fold decreased viral load in the supernatant of infected cells associated with a 38-fold decrease in virus growth. The advantage of our modified heparin is an increased antiviral effect compared to regular heparin.
This study investigates the surface quality and bacterial adhesion properties of various dental materials, including indirect composites, veneering composites, direct composites, polyether ether ketone (PEEK), and two millable polymethyl methacrylate (PMMA). Material specimens were processed following manufacturer instructions, initially evaluated for surface roughness and Streptococcus sanguinis (S. sanguinis) adhesion. Subsequently, toothbrushing simulation was employed to simulate aging, and changes in material surfaces were assessed via roughness measurements and bacterial adhesion testing. Prior to simulated aging, direct and indirect composites exhibited the lowest roughness values. However, after the simulated toothbrushing, veneering composites displayed the highest roughness levels. Both PMMA materials demonstrated the highest S. sanguinis adhesion levels, both before and after artificial aging. Interestingly, the indirect composite material showed a reduction in bacterial adhesion following toothbrushing simulation. Surprisingly, this study did not reveal a clear correlation between roughness and bacterial adhesion.
16 February 2024 in The Journal of Prosthetic Dentistry