Context: Disease Modifying Anti-Rheumatic Drugs (DMARDs) are aimed to interfere with rheumatoid arthritis (RA) progression and reduce the joint damage; however, not all patients respond alike. Killer-cell immunoglobulin-like receptors (KIR) and their ligands, human leucocyte antigen class I (HLA-I), have been associated with RA pathology; therefore, KIR and HLA genes may influence the treatment response. Materials and methods: We evaluated the association of KIR genotype and their ligands HLA-C genes with the response to DMARDs in RA patients. We included 69 patients diagnosed with RA and 82 healthy individuals as the reference group. KIR and HLA-C genotyping was performed using SSP-PCR. RA patients were assessed at baseline and under treatment at 6 and 12 months; subsequently classified as responders and non-responders in each time period. We evaluated the association between DMARD response and genes using statistical analysis by using Fisher exact test with Bonferroni correction; results were regarded as statistically significant at p < 0.05. Results: Significant difference was observed in gene frequencies of patients and the reference group, KIR2DL2 was associated with RA (p = 0.031, OR = 2.119). We also observed an association between KIR2DS2 and the response to methotrexate (MTX), moreover, the combination KIR2DL2+/KIR2DS2+ was more frequent in responders to MTX (p = 0.043). Discussion and conclusions: In our results, responders and non-responders to DMARDs showed KIR2DS2 and KIR2DL2 different gene frequencies, therefore, these genes could be used as response predictors to DMARDs treatment. Thus, these genes were also associated with disease severity, as well as the treatment response possibly by the immunoregulatory function of NK cells.

Introduction: Epstein-Barr Virus (EBV) infection prevails in underdeveloped and developing countries. The tonsils seem to be candidate replication sites for EBV and some studies have exposed a close association among viral infections and chronic tonsillitis. The objective of this study was identifying the EBV prevalence in Mexican patients who had undergone tonsillectomy because of chronic tonsillitis. Methodology: Frozen tissues and medical records were obtained from 50 Mexican patients. DNA was extracted and subjected to PCR to amplify the EBER-2 region of EBV. Next, the patients were classified according to general and clinical characteristics searching a relation with the EBV-DNA positivity. Results: EBV genome was detected in 46% (23/50) of the analysed tonsil tissues. Trends were found regarding the relationship of viral presence with lower values in terms of age (6.1 ± 2.8 vs 7.6 ± 3.7) , a greater degree of hypertrophy (3.5 ± 0.4 vs 3.0 ± 0.6) and an increase in the number of episodes of tonsillitis (11 ± 7.4 vs 9 ± 6.5). Conclusions: The prevalence found of EBV-DNA positivity in tonsillar tissues from patients diagnosed with chronic tonsillitis , supports the fact that palatine tonsils can be occupied by EBV and highlights the importance of conducting future studies focused on understanding the role of the EBV infection in chronic inflammatory processes in the population involved in this study.

Objective: Rheumatoid Arthritis (RA) is an autoimmune and chronic inflammatory disease of unknown etiology. Killer cell immunoglobulin-like receptors are expressed on the surface of natural killer cells and CD28null T-cells, both present in synovial membrane of RA. Therefore we evaluated the associations of KIR genes with RA.Methods: 16 KIR genes were genotyped in 100 healthy subjects (HS) and 100 RA patients from Western Mexico using PCR-SSP. Differences in KIR genotypes and gene frequencies were assessed using the X² test.Results: Gene frequency of KIR2DL3 was lower in RA than in HS (p = 0.0019), whereas KIR2DL2 and KIR2DS2 were higher in RA than HS (p = 0.0004 and p = 0.0487, respectively). In addition were identified 38 genotypes (from G1-G38) in both studied groups, and the genotype frequencies of G1, G6 and G14 showed significant differences (p = 0.0001, p = 0.0208 and p = 0.0300, respectively).Conclusions: The presence of KIR2DL2, KIR2DS2 and absence of KIR2DL3 are associated with RA. Moreover, two genotypes BX are associated with RA. These results suggest that KIRs can be involved in RA susceptibility.

Academic stress arises from students facing academic demands and is linked to various academic and psychological factors. However, research has yet to explore its potential correlations with somatization, overall health issues, studying strategies, academic procrastination, academic performance, and intelligence scores. The objective of this study was to determine the potential correlations between such variables with academic stress in a sample of health sciences university students. University students of different bachelor’s programs were invited to participate; they fulfilled an electronic questionnaire with personal and psychological variables, including academic stress, and performed an intelligence test, which measures verbal and non-verbal intelligence. Finally, their academic achievement was measured with the grade point average (GPA). A total of 437 students were included, of which 296 (67.7%) were women, with a mean age of 20.36 ± 2.61 years old. Academic stress was higher in women than in men and showed moderate positive correlations with anxiety, depression, and somatization and a low positive correlation with the sum of diseases. It also showed a low negative correlation with sleep quality. In addition, academic stress correlated negatively with self-motivation, emotion perception, and emotion management as well as with active coping, positive relations with others, and the studying strategies (self-regulation, effort regulation, critical thinking, and time and study environment). We also observed a low positive correlation between academic stress and academic procrastination, which was higher in women than in men. No correlations were found with GPA or intelligence scores. In conclusion, academic stress was positively correlated with somatization, depression, anxiety, the sum of diseases, and academic procrastination; it was negatively correlated with emotional intelligence (mainly self-motivation), active coping, and specific studying strategies.

This study examined the association between tumour necrosis factor-alpha (TNF- α) (–308 G/A) polymorphism and gingivitis, and serum and salivary TNF- α levels, in a Mexican population.This study en...