Gaceta medica de Mexico最新文献

Background: Protein interactions participate in many molecular mechanisms involved in cellular processes. The human TATA box binding protein (hTBP) interacts with Antennapedia (Antp) through its N-terminal region, specifically via its glutamine homopeptides. This PolyQ region acts as a binding site for other transcription factors under normal conditions, but when it expands, it generates spinocerebellar ataxia 17 (SCA17), whose protein aggregates in the brain prevent its correct functioning.

Objective: To determine whether the hTBP glutamine-rich region is involved in its interaction with homeoproteins and the role it plays in the formation of protein aggregates in SCA17.

Material and methods: We characterized hTBP interaction with other homeoproteins using BiFC, and modeled SCA17 in Drosophila melanogaster by targeting hTBPQ80 to the fly brain using UAS/GAL4.

Results: There was hTBP interaction with homeoproteins through its glutamine-rich region, and hTBP protein aggregates with expanded glutamines were found to affect the locomotor capacity of flies.

Conclusions: The study of hTBP interactions opens the possibility for the search for new therapeutic strategies in neurodegenerative pathologies such as SCA17.

Background: Suicidal behavior in adolescents is a growing public health problem. Knowing its risk factors is key for reducing it.

Objective: To identify the relationship between two suicidal behaviors (ideation and attempt) and eight mental health problems (MHPs) in Mexican adolescents.

Material and methods: Through an online survey of adolescent students from 20 states, the following information was screened: symptomatology of six MHPs (affective problems/depression, behavioral problems, somatic problems, inattention and hyperactivity problems, oppositional defiant problems and anxiety problems) and suicidal behavior (suicidal ideation and suicide attempts). MHP and suicidal behavior frequencies and percentages were analyzed, and associations were sought using binary logistic regression.

Results: Six-thousand seven hundred sixty-six adolescents completed the survey, out of whom 61.02% were females, with ages ranging between 11 and 19 years (16.38 ± 1.33); 10% reported suicidal behavior, and between 3 and 5%, MHPs. The predictors (χ²₍₈₎ = 387.13, p < 0.001) of suicidal behavior were affective problems/depression, behavioral problems, somatic problems, oppositional defiant problems and anxiety problems.

Conclusion: Five mental health problems increased the risk of reporting suicidal behaviors.

Background: Specific dietary compounds are essential for cognitive health.

Objective: To examine differences in the consumption of macronutrients and inorganic nutrients between people with a higher and lower risk of cognitive impairment.

Material and methods: Cross-sectional analysis of the 3Ollin study. Minimal Mental State Examination determined cognitive status. Two groups were obtained from the median of the score: higher and lower risk of cognitive deterioration. Diet was assessed using two 24-hour recalls. Descriptive statistics and comparison analysis of medians using Mann-Whitney U and Spearman correlation analysis were performed between nutrients and MMSE scores. The results were considered statistically significant when p ≤ 0.05.

Results: Data from 425 people were analyzed; the median age was 71 years (P25-P75 = 65-77). In the group with a lower risk of cognitive impairment, a higher consumption of calories, protein, carbohydrates, fiber, folate, phosphorus, ascorbic acid, vitamin E, alpha-tocopherol, vitamin B₆, vitamin B₁₂, zinc, selenium, and lycopene were observed. Also, a greater consumption of fruits and vegetables (p < 0.005).

Conclusions: There are significant differences in diet between groups at risk for cognitive impairment.

Background: Frailty has been related to adverse outcomes, but evidence on its association with the use of health services is still scarce.

Objective: The purpose of this work was to determine the association of frailty with the use of health services in Mexican adults older than 60 years.

Material and methods: Analysis of the Mexican Health and Aging Study for the years 2015 (baseline) and 2018 (follow-up). Frailty was defined with the frailty index. The following outcomes were included: hospitalization, medical visits, major surgery, minor surgical procedures, and dental visits. Competing risk and count analyses (negative binomial regression) were performed.

Results: A total of 8,526 individuals were included, whose average age was 70.8%; 55.8% corresponded to the female gender. According to the results, hospitalization days and the number of minor procedures were associated with frailty.

Conclusions: Frailty could be useful in the planning of health services for older adults. On the other hand, its evaluation would allow prioritizing care for those who are at higher risk of adverse outcomes.

Introduction: Dysphagia and cognitive impairment are common in older people. It is linked to alterations in brain areas related to swallowing.

Objective: To explore the characteristics of dysphagia using fluoroscopy in patients with mild cognitive impairment (MCI) and dementia.

Material and methods: 158 participants from a memory clinic. Specific criteria for MCI and dementia were used. Dysphagia was assessed with EAT-10 (≥ 3). Those who accepted completed a fluoroscopy study with a barium swallow to evaluate the phases of swallowing; the presence of bronchoaspiration supported the diagnosis of dysphagia. A logistic regression analysis was performed to test the probability between dysphagia and MCI.

Results: According to EAT-10, 86 (54.4 %) were at risk of dysphagia, confirmed in 84 by fluoroscopy, 53.8 % MCI group and 46.2 % dementia. An inverse association was observed in the MCI oral phase group (OR 0.23, p < 0.025), and a positive association; in protection phase against regurgitation (OR 3.76, p < 0.056) and laryngeal muscle contraction (OR 3.22, p < 0.045) versus dementia group.

Conclusions: The study showed a high frequency of dysphagia in patients with MCI, this highlights the importance of its early detection to improve complications associated with dysphagia.

Background: The usefulness of circulating free DNA (cfDNA), nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) as potential biomarkers in cancer remains controversial.

Objective: To determine the concentration of cfDNA and plasma nDNA and mtDNA levels in breast cancer (BC) patients.

Material and methods: This study included a total of 86 women (69 patients with BC and 17 women as a control group). The cfDNA was determined using fluorometry, and the levels of mtDNA and nDNA were quantified using real-time polymerase chain reaction (qPCR).

Results: The concentration of cfDNA was higher in patients with BC compared to the control group (p = 0.001). A higher concentration of cfDNA was also associated with patients over 50 years old (p = 0.001). The level of nDNA was higher in patients with CM compared to the control group (p = 0.004). Levels of mtDNA did not show significant differences (p > 0.005). The concentration of cfDNA and nDNA showed significant discriminatory power (AUC = 0.968, CI = 0.93-1.00, p = 0.001; and AUC = 0.724, CI = 0.59-0.85, p = 0.004, respectively.

Conclusions: The concentration of cfDNA and the combination of cfDNA and nDNA are useful biomarkers for diagnosing patients with BC.

Humans are exposed every day to innumerable external stimuli, both environmental and microbial. Immunological memory recalls each specific stimulus and mounts a secondary response that is faster and of a larger magnitude than the primary response; this process constitutes the basis for vaccine development. The COVID-19 pandemic offers a unique opportunity to study the development of immune memory against an emergent microorganism. Memory T cells have an important role in the resolution of COVID-19, and they are key pillars of immunological memory. In this review, we summarize the main findings regarding anti-SARS-CoV-2 memory T cells after infection, after vaccination, and after the combination of these two events ("hybrid immunity"), and analyze how these cells can contribute to long-term protection against the infection with SARS-CoV-2 variants.