Search Results (207)

Type 2 diabetes mellitus (T2DM) affects 90% of diabetes cases and worsens cardiovascular health by causing oxidative stress, which leads to oxidized LDL (oxLDL) and foam cell formation, contributing to atherosclerosis. This study examined the relationship between CD36 gene variants, soluble CD36 (sCD36), oxLDL, and MDA-LDL in T2DM and ST-segment elevation myocardial infarction (STE-T2DM) patients in western Mexico. The analysis included 400 T2DM patients, 400 STE-T2DM patients, and 400 healthy controls. Results showed that STE-T2DM patients were older, mainly male, and had higher rates of smoking, sedentarism, and hypertension. Both diabetic groups exhibited elevated triacylglycerols and low HDL, with significantly higher C-reactive protein in STE-T2DM (p < 0.0001). No significant differences in CD36 gene variant frequencies were found, but sCD36 levels were elevated in STE-T2DM, with associations to specific genotypes. oxLDL was higher in STE-T2DM compared to controls (p = 0.0268). Binary logistic regression analysis identified male sex, younger age, sedentarism, and rs3173798 T/T genotype as independent risk factors for myocardial infarction (AUC: 0.9267, p < 0.0001). Elevated sCD36 levels may reflect atherosclerosis progression in diabetes, indicating the need for further studies to clarify CD36’s role in cardiometabolic dysfunction. These findings highlight CD36’s involvement in oxidative stress responses through its interaction with oxLDL and MDA-LDL, suggesting its potential role as a molecular target in antioxidant defense mechanisms. Full article

Background/Objectives: Epstein–Barr virus (EBV) detection patterns in lymphoproliferative disorders (LPDs) show significant geographical variation worldwide. Regional epidemiological data are essential for understanding viral distribution patterns and developing appropriate clinical surveillance strategies. This study aimed to determine EBV detection frequency in LPDs using available molecular and immunohistochemical methods in Western Mexico. Methods: We conducted a cross-sectional study of 200 formalin-fixed paraffin-embedded tissue samples from patients diagnosed with LPDs (2015–2019) at Hospital Civil de Guadalajara. EBV detection combined with real-time PCR targeting the BNTp143 gene and immunohistochemistry for LMP-1 protein. Cases were classified following current WHO criteria. Statistical analysis included multivariate logistic regression, diagnostic concordance assessment, and age-stratified analysis. Results: EBV detection frequency reached 35.5% overall, with marked differences between neoplastic (53.9%) and reactive LPDs (24.2%) (OR: 3.515; 95% CI: 1.859–6.645, p < 0.001). Hodgkin lymphoma showed the highest detection rate (80.6%), significantly exceeding non-Hodgkin lymphoma (39.3%) (OR: 6.43; 95% CI: 2.08–19.41, p = 0.001). Age-stratified analysis revealed predominant adult involvement (49.1% vs. 22.0% in young adults, p = 0.025). We identified three epidemiological categories based on detection probability patterns. Conclusions: This study represents the first comprehensive molecular and immunohistochemical characterization of Epstein–Barr virus in lymphoproliferative disorders from Western Mexico, establishing distinct epidemiological patterns that align with Latin American regional characteristics. The validated methodology provides a reproducible framework for multi-center studies, while the epidemiological data serve as an essential baseline for future longitudinal research and resource optimization in similar healthcare settings. Full article

Objective: To evaluate the predictive risk factors associated with the prevalence of metabolic syndrome (MetS) in adolescents from the western region of Mexico. Materials and Methods: An analytical cross-sectional study was conducted with a sample of 516 adolescents. Anthropometric data, blood pressure, and biochemical determinations were obtained. The diagnosis of MetS was based on the criteria proposed by de Ferranti in 2004. The triglyceride–glucose index (TyG index) was calculated, where a value >4.68 indicates insulin resistance (IR). Risk factors associated with MetS were evaluated using a logistic regression model. The statistical analysis was performed with the level of statistical significance established was p < 0.05. Results: The MetS prevalence was 17.2% among adolescents. One out of every two adolescents with obesity presented with MetS. Abdominal obesity and dyslipidemia are the most common components. Predictors of MetS included male sex, early adolescence, waist-to-height ratio (WHtR) > 0.5, increased body fat percentage, and TyG Index > 4.68 (IR). In the sex-specific analysis, a WHtR > 0.5 and IR were associated with MetS in female adolescents. In male adolescents, IR and body fat percentage were associated with MetS. The WHtR was associated with IR, and hypertriglyceridemia was associated with elevated alanine aminotransferase. Conclusions: In this study, two out of ten adolescents presented with MetS. In boys, a high prevalence of abdominal obesity, hypoalphalipoproteinemia, insulin resistance and MetS was observed. The risk of developing MetS is greater in preadolescent boys with abdominal obesity, high levels of body fat, and a TyG index > 4.68. Full article

Background/Objectives: Cognitive impairment in older adults has emerged as a growing public health concern, particularly in relation to COVID-19 infection and its associated neuropsychiatric symptoms. The identification of modifiable risk factors may contribute to the development of targeted preventive strategies. This study aimed to assess predictors of cognitive impairment in older adults with and without recent SARS-CoV-2 infection. Methods: A prospective cohort study was conducted from June 2023 to March 2024 at a tertiary hospital in western Mexico. Adults aged 65 years or older with confirmed SARS-CoV-2 infection within the previous six months, along with uninfected controls, were enrolled. Cognitive function (Mini-Mental State Examination), depression (PHQ-9), anxiety (Geriatric Anxiety Inventory), insomnia (Insomnia Severity Index), functional status (Katz Index and Lawton–Brody Scale), and laboratory markers were evaluated at baseline, three months, and six months. The primary outcome was cognitive impairment at six months. Independent predictors were identified using a multivariable generalized linear mixed-effects model. Results: Among the 111 participants, 20 (18.8%) developed cognitive impairment within six months. Low serum magnesium (adjusted risk ratio [aRR] 2.73; 95% CI 1.04–7.17; p = 0.041) and depression (aRR 5.57; 95% CI 1.88–16.48; p = 0.002) were independently associated with a higher risk. A significant synergistic among COVID-19, depression, and hypomagnesemia was observed (RR 44.30; 95% CI 9.52–206.21; p < 0.001), corresponding to the group with simultaneous presence of all three factors compared to the group with none. Conclusions: Depression and hypomagnesemia appear to be independent predictors of cognitive impairment in older adults with recent COVID-19 infection. These findings suggest potential targets for prevention and support the implementation of routine neuropsychiatric and biochemical assessments in this population. Full article

Human exploitation has been a major driver of marine turtle population declines, particularly affecting naturally scarce species such as the pantropical hawksbill turtle. Although hawksbill sea turtles have been documented in the Gulf of California since the early 20th century, data on their historical demography during periods of high exploitation in this region are nonexistent. We investigated the size structure of hawksbill turtles from the Western Central Gulf of California by examining a unique sample of decorative taxidermies, corresponding to 31 specimens captured during fishing operations near Santa Rosalía, Baja California Sur, Mexico, between 1980 and 1990. An analysis of the curved carapace measures revealed a length range (nuchal notch to posterior of supracaudals) of 29.5–59.5 cm (mean = 38.75 ± 6.67 cm) and a width range of 25.0–51.5 cm (mean = 33.63 ± 5.66 cm), with 87% of specimens having lengths between 30 and 45 cm. Based on the carapace length measurements, we estimated the ages to be between 7 and 20 years, indicating that the population included juveniles. Our findings provide baseline data for an understudied period and region, suggesting that this area previously served as an important juvenile habitat. These results contribute essential historical demographic information for conservation planning. Full article

Anthropogenic disturbance alters macro- and microclimatic conditions, often increasing ambient temperatures. These changes can strongly affect insects, particularly those experiencing high thermal stress (i.e., large differences between body and environmental temperature), as prolonged exposure to elevated temperatures can reduce their energetic reserves due to increased metabolic demands and physiological stress. We evaluated thermal stress in 16 insect dragonfly species during two sampling periods (2019 and 2022) in preserved and disturbed sites within a tropical dry forest in western Mexico. Also, we compared energetic condition (lipid and protein content) and thoracic mass for the seven most abundant species between both habitat types. In preserved sites, insects showed higher thermal stress at lower maximum temperatures, which decreased as temperatures increased. Dragonflies in disturbed sites maintained consistent levels of thermal stress across the temperature gradient. Thermal stress was linked to lower lipid and protein content, and individuals from disturbed sites had reduced energy reserves. We also found a weak but consistent positive relationship between mean ambient temperature and protein content. In preserved sites, thoracic mass increased with thermal stress, but only at high mean temperatures. These findings suggest that although species can persist in disturbed environments, their energetic condition may be compromised, potentially affecting their performance and fitness. Preserving suitable habitats is essential for preserving both biodiversity and ecological function. Full article

The leafhopper genus Renonus is one of the rarest genera in the leafhopper tribe Athysanini. The Mexican endemic monotypic species, Renonus rubraviridis DeLong, is historically known from few localities, and since the original description, no additional data has been provided. During an ongoing survey conducted in western Mexico over the Seasonally Dry Tropical Forests, including the surroundings of the Estación de Biología Chamela (IB-UNAM), specimens of R. rubraviridis and others that do not morphologically fit with previously described species were collected. Herein, a new endemic species to Mexico, Renonus cuixmalensis sp. nov., is described and illustrated in detail. In addition, morphological notes of R. rubraviridis, the key to species, a map of distribution, a habitat description, and a discussion about the strong influence on distribution through the Seasonally Tropical Dry Forest are given. Full article

There is a need to evaluate Sentinel-2 (S2) fire severity spectral indices (SFSIs) for predicting vegetation and soil burn severity for a variety of ecosystems. We evaluated the performance of 26 SFSIs across three fires in seasonally dry oak–pine forests in central-western Mexico. The SFSIs were derived from composites of S2 multispectral images obtained with Google Earth Engine (GEE), processed using different techniques, for periods of 30, 60 and 90 days. Field verification was conducted through stratified random sampling by severity class on 100 circular plots of 707 m², where immediate post-fire effects were evaluated for five strata, including the canopy scorch in overstory (OCS)—divided in canopy (CCS) and subcanopy (SCS)—understory (UCS) and soil burn severity (SBS). Best fits were obtained with relative, phenologically corrected indices of 60–90 days. For canopy scorch percentage prediction, the indices RBR3c and RBR5n, using NIR (bands 8 and 8a) and SWIR (band 12), provided the best accuracy (R² = 0.82). SBS could be best mapped from RBR1c (using 11 and 12 bands) with relatively acceptable precision (R² = 0.62). Our results support the feasibility to separately map OCS and SBS from S2, in relatively open oak–pine seasonally dry forests, potentially supporting post-fire management planning. Full article

Dengue mortality has traditionally been associated with severe thrombocytopenia and hemorrhagic complications. However, during 2024, dengue virus serotype 3 (DENV-3) increased significantly in western Mexico, leading to the emergence of a distinct clinical pattern. We conducted a retrospective cohort study of hospitalized dengue patients at the General Hospital of Colima (January–August 2024). Clinical features, laboratory parameters, and outcomes were compared between survivors and non-survivors. Among 201 hospitalized patients, 6 (3.0%) died. All deceased patients presented with generalized seizures, polyserositis (pleural effusion and/or ascites), and required mechanical ventilation. Contrary to classical patterns, they did not have severe thrombocytopenia. Instead, they showed significantly higher white blood cell counts and notably increased levels of serum urea and BUN, suggesting early renal impairment. ROC analysis indicated that BUN (AUC 0.904) and urea (AUC 0.906) were good to excellent discriminators of mortality. During 2024, with an increase in DENV-3 circulation, mortality was associated with neurological and systemic complications, including seizures and polyserositis, as well as biochemical evidence of renal dysfunction—but not with severe thrombocytopenia. These findings challenge current paradigms and highlight the need for early recognition of atypical clinical patterns. Full article

The Placerias quarry is a dicynodont-dominated bonebed in Upper Triassic Chinle Group strata near St. Johns in east-central Arizona, USA. Though long identified as being in strata of the lower Chinle Group, recently published numerical ages apparently indicate a stratigraphically much higher (younger) position in the Chinle section for the Placerias quarry. Nevertheless, recent analysis of outcrop and subsurface (hydrologic) data in the vicinity of the Placerias quarry confirms its stratigraphic position very low in the Chinle Group section, close to the base of the Bluewater Creek Formation. A regional Upper Triassic lithostratigraphy has been established across east-central Arizona and west-central New Mexico by nearly a century of stratigraphic studies and geologic mapping by diverse workers, and is supported by biostratigraphy; in this lithostratigraphy the Placerias quarry is near the Chinle Group base. However, U/Pb ages on zircons from Upper Triassic strata in eastern Arizona/western New Mexico have been used to reorganize this lithostratigraphy to indicate intertonguing and dramatic lithofacies changes over relatively short lateral distances. But, if the well-established lithostratigraphy is followed, the U/Pb ages are problematic, particularly where younger ages (such as at the Placerias quarry) are stratigraphically below older ages. A handful of numerical ages should not be used to over-rule well-established understanding of lithostratigraphy and biostratigraphy, unless the lithostratigraphy and biostratigraphy need to be modified based on stratigraphic data. Numerical ages need to be used judiciously and evaluated critically with regard to established lithostratigraphy, biostratigraphy and other age constraints. Full article

Tuberculosis remains a significant health issue in Mexico, which has one of the highest incidence rates in the Americas. This study aimed to analyze the circulating sublineages, spoligotypes, drug resistance, and transmission patterns of Mycobacterium tuberculosis in Mexico’s Central Western region using whole-genome sequencing. Seventy-seven Mycobacterium tuberculosis strains underwent phenotypic drug susceptibility testing via MGIT. Genotypic resistance was assessed with TB-Profiler and Mykrobe, while phylogenetic relationships were reconstructed using Snippy and RaxML. SpoTyping identified circulating SITs and families, with a 5-SNP threshold defining genomic transmission clusters. The predominant sublineages were 4.1.1.3 (X-type, n = 19) and 4.1.2.1 (LAM, n = 11), with rare sublineages (EAI5, EAI2-Manila, and Beijing) also observed. Resistance to at least one first-line drug was found in 63.3% of strains, with streptomycin mono-resistance (24.5%) being notable. Multidrug-resistant TB was identified in 16.3% (n = 8) of strains. Five genomic clusters, involving 18.7% of strains, were identified. This study highlights the sublineage diversity in Mexico, emphasizing its importance in global databases and resistance research. The findings, such as SIT47 in GC1, underscore the value of localized genomic studies for effective TB control. Full article

This study investigated the spatial distribution and radiological risks of naturally occurring radionuclides (²²⁶Ra, ²³²Th, ⁴⁰K) in 37 soil samples from Zacatecas, located in north-central Mexico, using high-resolution gamma spectrometry. Results revealed ⁴⁰K concentrations (mean: 736.81 Bq kg⁻¹), nearly double the global average, while ²²⁶Ra (29.96 Bq kg⁻¹) and ²³²Th (29.72 Bq kg⁻¹) aligned with worldwide norms. Geoaccumulation indices identified moderate ⁴⁰K accumulation at 22 sites, with El Capulín classified as moderately contaminated (I_geo = 1.07). Radiological risk indices showed absorbed dose rates (62.52 nGy h⁻¹) and excess lifetime cancer risk (0.330 × 10⁻³) exceeding global thresholds by 4% and 14%, respectively. Multivariate analyses demonstrated strong Spearman correlations (ρ = 0.75–1.00) among risk indices, while spatial interpolation identified southern/western regions as high-risk zones. These findings emphasize the necessity of integrating spatial analysis with multivariate statistical techniques in environmental radioprotection frameworks. While most of the study area complies with international safety standards, the identified zones exceeding dose thresholds warrant prioritized management to mitigate potential cumulative health risks. Full article

Background/Objectives: A case-control study was conducted to determine the association of the −238 G>A and −308 G>A TNF-alpha (TNFA) promoter polymorphisms with mRNA and protein expression in 180 Systemic Lupus Erythematosus (SLE) patients and 186 control subjects (CS) from western Mexico. Methods: Genotyping was performed using the PCR-RFLP method. TNFA mRNA expression was assessed by real-time quantitative PCR, and soluble TNF-α (sTNF-α) levels were quantified by ELISA. For comparison groups, Chi-square, Mann–Whitney U, or Kruskal–Wallis tests were used. Spearman’s rank correlation coefficient determined the correlation between variables. The Area Under the Curve was used to determine the diagnosing performance of sTNF-α. Results: No differences were found in the genotype distribution of −238 G>A and −308 G>A TNFA polymorphisms between SLE patients and CS. However, the −238A allele was associated with increased SLE susceptibility (OR 1.18 CI 95% 1.02–3.50, p = 0.037). Also, logistic regression analysis showed that LN risk was significantly higher in carriers of the −308A allele (OR 3.11 IC95% 1.15–6.43; p = 0.002). On the other hand, the TNFA mRNA expression was 3.3-fold higher in SLE compared to CS. SLE patients with −308 GG genotype showed higher TNFA mRNA expression compared to GA+AA genotype carriers (p < 0.01). Regarding sTNFa levels, SLE patients showed higher concentration than CS, mainly in lupus nephritis (LN), with a weak negative correlation with estimated Glomerular Filtration Rate and an acceptable accuracy for diagnosing SLE and LN, with areas under the curve of 0.61 and 0.65, respectively. Conclusions: The −238 A allele and −308 A allele of the TNFA gene are linked to a higher risk of susceptibility to SLE and LN in the western Mexican population. Additionally, SLE patients exhibited increased TNF-alpha gene expression and sTNF-α, particularly in LN, demonstrating acceptable diagnostic performance. Full article

ACLF is a severe stage of liver cirrhosis, characterized by multiple organ failure, systemic inflammation, and high short-term mortality. The intestinal microbiota (IM) influences its pathophysiology; however, there are currently no studies in Latin American populations. Therefore, we analyzed IM and its relationships with sepsis, organ failure, and mortality. In parallel, we quantified serum lipopolysaccharides as a marker of bacterial translocation. Fecal samples from 33 patients and 20 healthy controls (HCs) were obtained. The IMs were characterized by 16S-rRNA amplicon sequencing, the metagenomic functional predictive profiles were analyzed by PICRUSt2, and LPS quantification was performed by ELISA. Patients with ACLF showed significant alterations in alpha and beta diversity compared to the HCs. A strong dominance index accurately predicted 28-day and 90-day mortalities. The IMs showed a polarization toward Proteobacteria associated with increased LPS. The LPS correlated with clinical severity, organ dysfunction, and higher pathogenic taxa. The Klebsiella/Faecalibacterium ratio showed good performance in identifying sepsis (AUROC = 0.83). Furthermore, Morganella, Proteus, and Klebsiella were enriched in patients with multiorgan failure. Lactobacillus, Escherichia/Shigella, Veillonella, and Ruminococcus gnavus exhibited potential in predicting 28- and 90-day mortalities. The IM alterations in ACLF may be useful as clinical biomarkers of poor prognosis, primarily for mortality and sepsis. These findings are representative of western Mexico. Full article

The Sierra Madre Occidental (SMO) is a biogeographic province of Mexico that serves as a corridor for the northward expansion of subtropical species, while also acting as a barrier for the movement of species between western and eastern Mexico. The SMO houses 57 species of amphibians and 160 species of reptiles, representing 19.4% of the total number of amphibian and reptile species found in Mexico. Ten amphibian and thirteen reptile species are endemic to the SMO, and >50% of amphibian and reptile species found in the SMO are endemic to Mexico. Five amphibian species and three reptile species are listed in a category of conservation concern in the IUCN Red List. Specific threats include habitat loss, logging, mining, pollution, and climate change. The SMO shares a significant percentage of its species with neighboring provinces. In the cluster analysis for amphibians, a group comprising the SMO, the Pacific Lowlands, and the Chihuahuan Desert is linked to the Transvolcanic Belt. For reptiles, two distinct groups emerge: one including the SMO and the Chihuahuan Desert and one including the Transvolcanic Belt and the Pacific Lowlands. In conclusion, the rich biodiversity of the SMO, along with its role as both a corridor and barrier for species distribution, highlights the importance of targeted conservation efforts to mitigate the various threats facing this biogeographically significant province. Full article