Knowledge, Attitude, and Practice towards Chelating Agents in Endodontic Treatment among Dental Practitioners

The use of chelating agents (CAs) in the endodontic irrigation protocol is required to dissolve the inorganic components of the smear layer. We aimed to assess the knowledge, attitude, and practice of dental professionals regarding the use of CAs during root canal treatment. A cross-sectional anonymous online survey was conducted among specialized endodontists and general dentists who routinely perform endodontic treatment and work in government-funded or private clinics in Moscow. The 8 min survey consisted of four parts: basic demographic data, knowledge (five items), attitude (four items), and practice (five items). We collected 376 completed questionnaires; a majority of the respondents were general dentists (87.5%) and worked in private clinics (77.4%). Most respondents (83.5%) showed a fair knowledge of the CAs used in endodontics, while 16.5% showed a poor knowledge of the topic. Small yet significant differences were found between endodontists and general practitioners and between dentists employed by private and government-funded clinics. A majority of dental practitioners (83%) demonstrated a positive attitude towards the use of CAs in endodontic treatment, and there were no differences among the study subgroups. Almost a third of the respondents always used chelating solutions during endodontic treatment, while 17% of the respondents did not use them at all. There were significant differences in this parameter between dentists working in private and government-funded clinics. Practice significantly correlated with attitude towards chelating agents and with knowledge of the topic. In conclusion, dental practitioners demonstrated a fair knowledge of CAs. Despite a positive attitude, 71% of the respondents did not use CAs for all endodontic patients.

Creation of Polymer Hydrogel Dressings with Herbal Medicinal Substance "Alkhydin" and their Properties

New hydrogel dressings containing the herbal medicinal substance "Alkhydin", obtained from the Kirghiz (Alhagi kirghisorum Schrenk), grown in Kazakhstan, were obtained by radiation irradiation of the initial reaction mixture (IRM). Poly-<br />N-vinylpyrrolidone (PVP) with a molecular weight (MM) of 1 ppm was used to prepare hydrogel dressings as the main gelling polymer for IRM, agar-agar and lowmolecular polyethylene glycol MM = 600 were used as auxiliary substances. The main regularities of the formation of the three-dimensional structure of PVP under conditions of irradiation of IRM are investigated. It is shown that with increasing PVP in IRM, as well as irradiation dose, the yield of gel fraction increases and the degree of swelling decreases. Obviously, these effects are due to an increase in the degree of cross-linking of the polymer network formed. For the obtained hydrogel dressings containing the herbal medicinal substance Alkhydin, cytotoxic effects on the culture of mouse embryonic fibroblasts obtained by primary trypsinization were studied. The results obtained in this case testify to the absence of a cytotoxic effect on the cell culture. In conditions "in vivo" in rats using the model of thermal skin burn, the wound healing effect of hydrogel dressings with "Alkhydin" was studied. It is shown that such bandages show a pronounced wound-healing effect. This is evidenced by a higher rate of reduction in the area of the burn wound treated with a hydrogel dressing compared to the control.

RAC, a stable ribosome-associated complex in yeast formed by the DnaK-DnaJ homologs Ssz1p and zuotin

The yeast cytosol contains multiple homologs of the DnaK and DnaJ chaperone family. Our current understanding of which homologs functionally interact is incomplete. Zuotin is a DnaJ homolog bound to the yeast ribosome. We have now identified the DnaK homolog Ssz1p/Pdr13p as zuotin's partner chaperone. Zuotin and Ssz1p form a ribosome-associated complex (RAC) that is bound to the ribosome via the zuotin subunit. RAC is unique among the eukaryotic DnaK-DnaJ systems, as the 1:1 complex is stable, even in the presence of ATP or ADP. In vitro, RAC stimulates the translocation of a ribosome-bound mitochondrial precursor protein into mitochondria, providing evidence for its chaperone-like effect on nascent chains. In agreement with the existence of a functional complex, deletion of each RAC subunit resulted in a similar phenotype in vivo. However, overexpression of zuotin partly rescued the growth defect of the Delta ssz1 strain, whereas overexpression of Ssz1p did not affect the Delta zuo1 strain, suggesting a pivotal function for the DnaJ homolog.