AREAS COVERED: This review presents a summary of the adenosine receptor distribution in retina and the cellular functions mediated by them. The major pathophysiological mechanisms such as excitotoxicity, vascular dysregulation, loss of neurotrophic signaling, and inflammatory responses involved in glaucomatous RGC loss are discussed. The literature showing the role of adenosine receptors in modulating these pathophysiological mechanisms is discussed. The literature search was conducted using Pubmed search engine using key words such as 'RGC apoptosis,' 'adenosine,' adenosine receptors' 'retina' 'excitotoxicity,' 'neurotrophins,' 'ischemia', and 'cytokines' individually and in various combinations.
EXPERT OPINION: Use of adenosine receptor agonists and antagonists, for preservation of the RGCs in glaucomatous eyes independent of the level of intraocular pressure seems a very useful strategy. Future application of this strategy would require appropriate designing of drug formulation for tissue and disease-specific receptor targeting. Furthermore, the modulation of physiological functions and potential adverse effects need further investigations.
AREAS COVERED: Herein, the authors discuss the various factors that contribute to the quality of studies using animal models based on the evaluation of studies published in 2022. The factors affecting the quality of studies using animal models, such as the animal species, age, and sex, are discussed, along with various methods and outcomes of studies involving different animal models of glaucoma.
EXPERT OPINION: Translating animal research data to clinical applications remains challenging. Our observations in this review clearly indicate that many studies lack scientific robustness not only in their experiment conduct but also in data analysis, interpretation, and presentation. In this context, ensuring the internal validity of animal studies is the first step in quality assurance. External validity, however, is more challenging, and steps should be taken to satisfy external validity at least to some extent.
Materials and Methods: This randomized controlled trial was conducted on 40 healthy children aged between 10 and 12 years of age who were randomly assigned to either of the groups: Group I--Chewable Toothbrushes and Group II--Manual Toothbrushes. Following oral prophylaxis, baseline records of oral hygiene indices (Simplified oral hygiene index (OHI-S) in indexed teeth and Turesky modification of Quigley Hein plaque index (TMQHI) were taken. Baseline Saliva samples were collected and sent for Streptococcus mutans counts. Children were then instructed to use their respective toothbrush twice daily for a week. Oral hygiene indices and S. mutans counts were repeated after 1 week.
Results: Differences in pre-brushing and post-brushing plaque scores and salivary S. mutans counts were statistically significant when compared using paired-sample t test and independent-sample t test. There was a significant reduction in salivary S. mutans counts after using both chewable and manual toothbrushes. However, there was no statistically significant difference between the two groups (P = 0.08).
Conclusion: Chewable toothbrushes are equally effective in plaque control when compared to manual toothbrushes. These can be a reliable alternative for children who lack manual dexterity.
MATERIALS AND METHODS: A total of 60 subjects were selected for this study. 40 subjects presented with periodontitis, which included 20 snuff users (SP) and 20 nonsnuff users (NS). 20 periodontally healthy patients formed the controls (healthy control: HC). The clinical parameters recorded were gingival index (GI), plaque index, calculus index, bleeding on probing (BOP), probing depth (PD), recession (RC), and clinical attachment level (CAL). The IL-1 β and IL-8 levels were assessed through enzyme-linked immunosorbent assay (Quantikine(®)). Analysis of variance (ANOVA), post-hoc Tukey's, Kruskal-Walli's ANOVA and Mann-Whitney test was used for comparison among groups and P > 0.05 was considered statistically significant.
RESULTS: No significant difference was seen in levels of IL-1 β and IL-8 between SP and NS groups (P = 0.16, 0.97). However, both the periodontitis groups (SP and NS) had increased IL-β levels when compared to HC group (P = 0.01, 0.001). The snuff users showed significant increase in GI, BOP, RC, and CAL when compared with NS (P = 0.002, 0.001, 0.012, 0.002) whereas NS group had significant increase in PD (P = 0.003).
CONCLUSION: Within the limitations of this study, use of snuff does not affect the host inflammatory response associated with periodontitis and leads to RC and increased CAL due to local irritant effect.