RESUMEN
Amyloid-beta (Aß)-related alterations, similar to those found in the brains of patients with Alzheimer's disease, have been observed in the retina of patients with glaucoma. Decreased levels of brain-derived neurotrophic factor (BDNF) are believed to be associated with the neurotoxic effects of Aß peptide. To investigate the mechanism underlying the neuroprotective effects of BDNF on Aß1-40-induced retinal injury in Sprague-Dawley rats, we treated rats by intravitreal administration of phosphate-buffered saline (control), Aß1-40 (5 nM), or Aß1-40 (5 nM) combined with BDNF (1 µg/mL). We found that intravitreal administration of Aß1-40 induced retinal ganglion cell apoptosis. Fluoro-Gold staining showed a significantly lower number of retinal ganglion cells in the Aß1-40 group than in the control and BDNF groups. In the Aß1-40 group, low number of RGCs was associated with increased caspase-3 expression and reduced TrkB and ERK1/2 expression. BDNF abolished Aß1-40-induced increase in the expression of caspase-3 at the gene and protein levels in the retina and upregulated TrkB and ERK1/2 expression. These findings suggest that treatment with BDNF prevents RGC apoptosis induced by Aß1-40 by activating the BDNF-TrkB signaling pathway in rats.
RESUMEN
BACKGROUND: To assess the quality of endodontic record-keeping and root canal obturation performed by undergraduate final year dental students during the COVID-19 pandemic. MATERIALS AND METHODS: Dental records and dental radiographs of patients who received endodontic treatments between March 2020 and March 2022 by undergraduate students during the COVID-19 pandemic were included. The audit data were collected based on the European Society of Endodontology guidelines retrospectively via assessing the patient's clinical records and intraoral periapical radiograph. Root canal obturation quality was evaluated based on the following parameters: adaptation, length, taper, and mishap. A root filling is defined as satisfactory only when all four parameters were graded as acceptable. Subsequently, the data were recorded and analysed using Chi-Square test with the level of significance set at p = 0.05. RESULTS: A total of 111 patient records with 111 root canal-treated teeth were evaluated. The highest percentage of documented evidence was noted in the patient's general records, while the endodontic treatment records showed the lowest percentage of documented evidence. 78 (70.3%) of root canal-treated teeth were deemed satisfactory with acceptable adaptation, length, taper, and absence of mishap. Moreover, no statistical significance in terms of root canal filling quality was noted between anterior and posterior teeth, and between maxillary and mandibular arch. CONCLUSIONS: Although patient records and root canal fillings quality were deemed satisfactory in most cases, strict documentation requirements and continuing dental education in audit training are necessary for quality assurance.