Eliud Alfredo Garcia Montalvo

Background/Objectives: Depression ranks among the most prevalent mental health disorders worldwide. Numerous studies have linked the C-1019G (rs6295) polymorphism in the serotonin 1A (5-HT1A) receptor gene to increased susceptibility to depression. In this study, sociodemographic variables and clinical characteristics were integrated with targeted genotyping of the C-1019G polymorphism to identify risk factors associated with depressive symptoms in a Mexican cohort. Methods: Sociodemographic and clinical data were collected from 257 volunteers (202 healthy controls, 55 with depressive symptoms). Genotyping for C-1019G was performed using polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP). Sociodemographic variables, clinical characteristics, and genotype frequencies were analyzed relative to Beck Depression Inventory II (BDI-II) scores. Results: BDI scores were significantly lower among males, participants aged < 40 years, unmarried individuals, and those with a high school education (p < 0.05). Females were three times more likely to exhibit depressive symptoms than males (p = 0.004; OR = 3.08). Compared with participants aged < 40 years, those aged 40–65 and >65 years were two (p = 0.026; OR = 2.19) and five times (p < 0.001; OR = 5.71) more likely to report depressive symptoms, respectively. Participants with type 2 diabetes mellitus had twice the odds of depressive symptoms (p = 0.025; OR = 2.38). Odds increased twelvefold among those with diabetes plus arterial hypertension (p < 0.001; OR = 12.25). Among males, the C/C genotype was observed exclusively in controls (p = 0.010). Furthermore, the genotypic distribution of this study population differed from that of European and Asian populations. Conclusions: These findings advance the understanding of depressive symptoms’ multifactorial etiology and may inform targeted screening and prevention strategies.

In this study, 104 purified water samples were collected from vending machines in the three main cities of Michoacan, Mexico, to assess microbiological quality and the occurrence of diarrheagenic Escherichia coli pathotypes (DEP) and nontuberculous mycobacteria (NTM). Aerobic mesophilic bacteria were detected in all samples, with concentrations ranging from 0.95 to 3.71 log₁₀ CFU/mL. A total of 62, 34, and 25 samples tested positive for total coliforms, fecal coliforms, and E. coli, respectively. Sixty-two samples exceeded Mexico’s official guideline. None of the 58 E. coli strains isolated from the 25 E. coli-positive samples belonged to DEP. NTM species were recovered from 47 samples, including M. mucogenicum (n = 18), M. abscessus (n = 11), M. chelonae (n = 7), M. porcinum (n = 3), M. fortuitum (n = 2), M. septicum (n = 1), M. phocaicum (n = 1), and M. brisbanense (n = 1). Three additional isolates could not be identified. All NTM strains produced biofilm and exhibited sliding motility. These findings highlight significant microbiological risks associated with vending machine water and underscore the need for manufacturers to ensure regular maintenance to provide safe and reliable purified water to consumers.

Background: Depression is one of the most prevalent mental health disorders worldwide, affecting a significant proportion of the global population. Its etiology is complex and influenced by the interaction of environmental factors and genetic variations. In Mexico, it has been reported that 41.3% of the population exhibits depressive symptoms. Previous studies have suggested that susceptibility to depression may be associated with the C-1019G (rs6295) polymorphism in the serotonin 1A (5-HT1A) receptor gene. Objective: In this study, we aimed to evaluate the association between the C-1019G polymorphism and depressive symptoms in a rural Mexican population. Methods: Using polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP), we examined the effect of C-1019G on depression symptoms, as evaluated by the Beck Depression Inventory. Data were obtained from 83 volunteers; individuals with depressive symptoms and those with a healthy mood were compared. Results: The results showed that the homozygous C/C genotype was found significantly more frequently in the control group than in individuals with depressive symptoms, particularly among men, and is thus associated with a decreased risk of depressive symptomatology. Conclusions: The C/C genotype could protect against susceptibility to developing depressive symptoms in a rural population in Mexico.

Selenium (Se) is an essential component of several major metabolic pathways and controls immune function. Arsenic (As) is a human carcinogen with immunotoxic and genotoxic activities, functioning mainly by producing oxidative stress. Due to the ability of Se to interact with As and to possibly block its toxic effects, we investigated the impact of dietary Se-methionine (Se-Met) supplementation on the toxicity of As exposure in vivo in a mouse model. Sufficient and excess levels of Se-Met (0.2 and 2 ppm, respectively) were fed to C57BL/6N female mice exposed to sodium arsenite (3, 6 and 10 mg/kg) in tap water for 9 days. We observed that As exposure increased Se-Met excretion in the urine. Se-Met supplementation increased the relative liver weight and decreased the concentration of total liver proteins in animals exposed to 10 mg/kg of As. Se-Met supplementation maintained a normal pool of glutathione in the liver and increased glutathione peroxidase concentration, although the lipoperoxidation level was increased by Se-Met even without As exposure. Se-Met supplementation helped to maintain the CD4/CD8 ratio of lymphocytes in the spleen, although it increased the proportion of B cells. Se-Met supplementation prior to As exposure increased the secretion of interleukin-4, IL-12 and interferon-γ and the stimulation index of the spleen cells in in vitro assays. Se-Met intake improved the basal immunological parameters but did not reduce the damage caused by oxidative stress after low-dose As exposure.

The study was aimed at determining the prevalence of overweight and obesity in indigenous nahuas from Ixtaczoquitlán, Veracruz, Mexico. For this purpose, a cross-cut study was conducted between 2010 and 2011, in which the body mass index (BMI) was calculated. To define overweight and obesity, the categories of the World Health Organization (WHO) and the Mexican Official Standard (NOM, Spanish acronym) were used. 227 nahuas (77,5% women) were included. According to WHO’s guidelines, the rate for overweight among nahuas was 41%, and 36.5% for obesity; according to NOM, it was 11.4 and 69.2% respectively. In conclusion, the prevalence of overweight and obesity among indigenous nahuas is high. Studies should be conducted to determine the prevalence and risk factors in order to develop prevention strategies based on this information to improve the health quality of these populations.

Inorganic arsenic (iAs) exposure has been associated with the increased risk of various forms of cancer and of non-cancerous diseases. Metabolic conversions of iAs that yield highly toxic and genotoxic methylarsonite (MAs^III) and dimethylarsinite (DMAs^III) may play a significant role in determining the extent and character of toxic and cancer-promoting effects of iAs exposure. However, in vivo research involving the production of MAs^III and DMAs^III remains an area of ongoing investigation and debate. The results of metabolic and toxicity studies using mice have been entirely applicable to other species including humans. The goal of this study was to investigate the phenotype for the trivalent and pentavalent arsenic metabolites in relation to arsenite dose via immediate analysis of fresh urine samples, while preventing the oxidation of unstable methylated As^III-containing metabolites. Female mice (C57BL/6) received sodium arsenite by gavage at doses of 0, 3, 6 or 10 mg As/kg/day for 9 days, after which trivalent methylated arsenicals were detected in 100% of urine samples; these arsenicals were not detected in the urine of control mice. The amount of DMAs^III detected in urine depended on the dose of arsenite administered and was determined to be 50.2%, 31.4% and 16.5% of the total urinary arsenic in mice exposed to 3, 6, or 10 mg/kg/day, respectively. This relationship is consistent with the hypothesis of inhibition or saturation of iAs methylation. Understanding the in vivo production of MAs^III and DMAs^III in mice exposed to iAs could aid in developing a biologically based dose-response model for iAs.