Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
Browse
Search Results
- Digital PCR analysis of ALS plasma miRNA biomarkers: towards analytical consistency and pathogenic relevance(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2025-06-10) Muñoz Arteaga, José Antonio; Díaz Durán, Raquel Cuevas; emipsanchez; Paul, Sujay; Pérez Martínez, Leonor; Fajardo Ramírez, Oscar Raúl; Escuela de Medicina y Ciencias de la Salud; Campus MonterreyAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease marked by motor neuron degeneration without properly standardized molecular biomarkers for early diagnosis or disease monitoring. Diagnosis remains primarily clinical, often involving lengthy exclusion processes and significant delays, highlighting the need for minimally invasive, accessible, and disease-specific molecular tools. Circulating microRNAs (miRNAs) are promising biomarker candidates due to their stability in plasma/serum and roles in gene regulation. This study aimed to quantify the expression of selected ALS-associated plasma miRNAs using digital PCR (dPCR) and compare them against those in healthy controls to validate their efficacy as early ALS biomarkers. Plasma samples were collected from eight ALS patients and four age-and-sex-matched healthy controls. Four candidate target miRNAs (hsa-miR-93-5p, hsa-miR-181a-5p, hsa-miR-206, hsa-miR-7111-3p) and one endogenous control (hsa-miR-191-5p) were selected via systematic review. Total miRNA concentration did not significantly differ between ALS patients and controls, suggesting global miRNA levels are not altered in ALS. Hsa-miR-206 was consistently upregulated across all analysis strategies, supporting its role as a robust biomarker. Hsa-miR-93-5p also showed significant differential expression, though results were dependent on normalization approach. Correlation analysis with ALS Functional Rating Scale-Revised (ALSFRS-R) scores revealed moderate but non-significant trends for both miRNAs. Target prediction analysis linked both miRNAs to ALS-associated genes, suggesting potential involvement in disease pathways. The study concludes that miR-206 is a promising candidate for clinical translation as a diagnostic and prognostic biomarker. It also emphasizes the importance of methodological standardization in miRNA research to ensure reproducibility and clinical applicability. Further validation in larger cohorts is necessary to confirm these findings.
- Quality assessment and validation of digital PCR (dPCR) for grapevine virus diagnosis(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2024-12-11) Hernández Pérez, Daniella María Joselyn; Díaz Lara, Alfredo; emipsanchez; Carrillo Tripp, Jimena; Rodríguez García, Manuel; School of Engineering and Sciences; Campus MonterreyGrapevine is a highly economically important crop in Mexico. However, it can be affected by several pathogens, including viruses that can cause significant crop losses. It is important to identify early the infected plants to manage the disease correctly and prevent economic losses. Traditional detection methods have drawbacks, such as limited sensibility and accuracy. Digital PCR (dPCR) is an innovative method that claims to be more sensitive and reproducible than the routine method for virus identification: quantitative PCR (qPCR). This study assesses reverse transcription dPCR (RT-dPCR) as a method for the detection and quantification of RNA grapevine viruses focusing on grapevine virus A (GVA), grapevine fanleaf virus (GFLV), grapevine leafroll-associated virus 3 (GLRaV-3), and grapevine Pinot gris virus (GPGV). This assessment was performed using positive controls and comparing the limit of detection (LoD) results of RT-dPCR against the results obtained by RT-qPCR. ANOVA results showed that the PCR technique (RT-dPCR or RT-qPCR) and the virus (GVA, GLFV, GPGV, and GLRaV-3) were statistically significant in the results of the comparison of LoD. Furthermore, the replicates were non-significant according to ANOVA, showing high repeatability in both RT-qPCR and RT-dPCR. Tukey test demonstrated that RT-dPCR is significantly more sensitive than RT-qPCR, with a statistically reliable difference of 95% trust, especially in low-viral-load viruses such GPGV, which detection showed also to be statistically different than the other viruses. Additionally, a field study was performed to identify the presence or absence of each virus in 45 grapevine samples evaluated with RT-qPCR and RT-dPCR. Several false negative results were generated by RT-qPCR, which only reported positive results to 62.5% of the GVA infected samples, 85.7% of the samples contaminated with GLRaV-3, 38.9% of GPGV positive samples and for GFLV only 12.5% of the infected samples were identified. These results confirm the effectiveness of RT-dPCR as a sensitive method for RNA virus detection in grapevine, enabling early diagnosis and optimal management of viral infections in grapevine crops.