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A temporary seismic network installed in September 2017 in La Primavera Caldera, next to the Guadalajara Metropolitan Zone (GMZ), recorded numerous events, ML ≤ 3.8, corresponding to background seismicity and swarms observed for four months. In this study, we located 188 tectonic microearthquakes from September 2017 to 1st January 2018, mainly in Tesistán Valley, north of GMZ. In addition, we identified 11 clusters of similar events from a spatio-temporal analysis and waveform cross-correlations. The microseismicity array suggests the possibility of synthetic faults; these are NE-SW and N-S oriented faults crossing Tesistán Valley, whose seismogenic depths are close to 10 km. Furthermore, most ML≥ 2.5 events and some clustered events are located in northeastern Tesistán, close to the NNE-SSW fault corresponding to the eastern edge of the Zapopan Graben, a structure evidenced by 2015-2016 seismicity. Moreover, seismicity recorded during 2020 by a recent local seismic network installed in Zapopan reaffirm that frequent microseismicity is related to active faults that cross Zapopan and Guadalajara cities. This seismicity in the northeast boundary of Jalisco Block is closely related to faults formed by Cenozoic deformation events that might be reactivated due to crustal arrangements. Our results demonstrate the existence of continuous seismicity in GMZ that, unfortunately, was not monitored for a more extended period. Active faults and the possibility of synthetic structures is a hypothesis that requires ongoing studies and seismic monitoring and thus contributes to assessing the seismic hazard in the GMZ, which is a crucial factor for urban planning.

The crustal structure around the Islas Marías Archipelago has been debated for a long time. An important unresolved question is where the Rivera-North American plate subduction ends and the Tamayo fracture zone begins, from SE to NW. Results from the TsuJal project have shed light on the northwesternmost part of the Jalisco block structure. It is now clear that Sierra de Cleofas and the Islas Marías Escarpment comprise the northwestern continuation of the Middle America trench. However, other questions remain. In this paper, we present the structure of the shallow and deep crust and the upper mantle of the Islas Marías western region through the integration of multichannel seismic reflection, wide-angle seismic bathymetric and seismicity data, including records of an amphibious seismic network, OBS, and portable seismic stations, purposely deployed for this project, providing an onshore-offshore transect of 310km length. Our findings disclose new evidence of the complex structure of the Rivera plate that dips 8°–9° underneath the NW Jalisco block as revealed by two seismic profiles parallel to the Islas Marías Escarpment. Moreover, we find five sedimentary basins and active normal faults at the edges of tectonic structures of the E-W oriented West Ranges and the N-S trending Sierra de Cleofas. Furthermore, the Sierra de Cleofas is the beginning of the active subduction of the Rivera plate beneath North America. The oceanic crust thickens and submerges towards the south while is coupled with the continental crust, from 6km at the northern ends of the seismic profiles to 15km in the contact region and 24km at the coast and southern ends of them. The continental Moho was not fully characterized because of the geometry of the seismic transects, but a low-velocity layer associated with Rivera Plate subduction was observed beneath the Jalisco Block. Our results constrain the complexity of the area and reveal new structural features from the oceanic to continental crust and will be pivotal to assess geohazards in this area.

The tectonic interaction between the Rivera and North American plates north of the Bahía de Banderas is poorly understood. The nature of the crust and where the subduction ends in the western part of the Islas Marias Archipelago are still controversial. Based on new geophysical data provided by the TsuJal project, we present the shallow and deep crustal structure of the Rivera–North American plate contact zone along two seismic transects, TS09b and RTSIM01b, and the bathymetry obtained across the northern region of María Madre Island. Detailed bathymetric analysis allowed mapping of a series of lineaments along the study region, with two main preferred tendencies (020–050° and 290–320°) associated with the evolution of the Pacific-Rivera rise and the transform faults of the Gulf of California, respectively. The shallow structure is characterized by five sedimentary basins without deformation, whose horizons are subparallel, suggesting that the sediment deposition occurred after the extension process ended. The deep structure corresponds to a transition between oceanic crust (Rivera Plate), with an average thickness of ∼10 km to the Islas Marías Escarpment, and a thinned continental crust, whose thickness increases toward the continent until it reaches 28 km, with a dip angle of 7–10°. The absence of an accretionary prism suggests that the subduction process of the Rivera Plate beneath the North American Plate to the north of Islas Marías has ceased. In this study, we determined that the morphological expression of the northern limit of the Rivera Plate corresponds to the Islas Marías Escarpment.

Objetivos: Describir las características clínico epidemiológicas, la calidad de los datos consignados y los tiempos de atención del servicio de emergencia de un hospital general durante el 2016. Material y métodos: estudio descriptivo, longitudinal. Se realizó seguimiento diario a los pacientes y se revisaron historias clínicas, registros de observación, trauma shock y tópico de medicina durante Setiembre y Octubre del 2016. Resultados: Hubieron 315 atenciones, 156 (49,5%) fueron mujeres; la mediana del tiempo de estancia en emergencia fue = 2,0 días, p25-75= 1-17 días; 76,85 % tuvieron estancia mayor de 24 horas; hubieron 2,2% reingresos y 11,7% fallecieron. Los datos con mayor frecuencia de no registro fueron: hora de egreso: 126 (40,1%), fecha de egreso: 104 (33,1%) y prioridad de ingreso: 101 (32%). Conclusiones: la frecuencia de estancia hospitalaria prolongada, de reingreso y de mortalidad en emergencia, fue elevada; se halló una considerable frecuencia de datos no registrados en las historias clínicas.

Objective: To characterize levels of pepsinogen and evaluate the discrimination ability of pepsinogen I (PGI) and the PGI/ pepsinogen II (PGII) ratio for the serological diagnosis of gastric atrophy in different Colombian populations. Methods: A total 600 subjects without gastric symptoms participated and 544 samples from patients with gastric symptomatology were analyzed from different populations with opposing risks to gastric cancer. A blood sample was taken from all participants; a gastric antrum and body biopsy for the initial diagnosis of gastroduodenal lesions was obtained from the patients. The levels of pepsinogen and Helicobacter pylori serology were estimated with ELISA. Statistical analyses included Kruskal -Wallis and Mann -Whitney test, ROC curve and diagnostic values. Results: The levels of PGI and PGI / PGII differ by risk area of origin. Levels of PGI, PGII and PGI / PGII decreased with increasing severity of histological diagnosis (P < .005), as with the severity of atrophy and multifocal localization (P ≤.001). The PGI ≤ 86.68 and PGI / PGII ≤ 3.19 with an area under the curve of 0.76 identified patients with severe multifocal atrophy, positive serology for H. pylori, and from the high risk area, with a sensitivity of 77.5% and specificity of 71.74%. Conclusion: The results suggest that PGI levels together with PGI / PGII ratios and positive serology for H. pylori could be considered for the detection of severe atrophy in high-risk areas. Further studies are needed in high-risk populations © 2014 Instituto Nacional de Cancerologia. Published by Elsevier Espana, S.L.U. All rights reserved.

Resumen Objetivo Detectar mutaciones del oncogen Ha-RAS en fibroblastos del estroma de biopsias de la zona de transformacion del cuello uterino. Metodos Se seleccionaron ocho muestras de tejido fresco congelado de pacientes diagnosticadas con neoplasia intraepitelial de cuello uterino, de tipo escamoso (NIC I, NIC II, NIC III), cancer in situ y carcinoma escamocelular infiltrante, tejido en el cual solo se encontraba representado el estroma, sin evidencia de componente epitelial tumoral residual, y para cada uno de los cuales se contaba con el tejido cervical de control incluido en parafina, que confirmaba la presencia de proceso neoplasico escamoso cervical. La deteccion de mutaciones Ha-RAS codon 12 fue realizada mediante un PCR-SSCP no radiactivo y analisis enzimatico de restriccion. Resultados La mutacion hallada para un cambio de una glicina por una valina en el codon 12 del oncogen Ha-RAS fue detectada en una sola muestra (12,5%), NIC III. Conclusiones La presencia de una alteracion molecular, mutacion puntual del oncogen Ha-RAS en el estroma de uno de estos casos analizados, representa un cambio importante, y sugiere una via alterna que podria involucrar inestabilidad genetica estromal en la generacion de neoplasias intraepiteliales y progresion del cancer de cuello uterino.

The stroma is maintained, renovated, and repaired by resident fibroblasts, supports and instructs the epithelium, and is essential for epithelial function. Now recognized that stromal changes are necessary for the establishment of cancer and previously considered as a spectator in front of the clonal expansion and acquisition of malignant characteristics of tumor cells. Most studies on the stroma and t its relationship with the generation, progression and metastasis of cancer in which involve multiple steps of tumorigenesis and the microenvironment, have focused especially on cancers such as breast and others as cancer of prostate, gastric, colorectal and cervical cancer. Reports of cervical cancer specifically address issues such as clonality and genomic features in cervical carcinogenesis. However, the presence of mutations Ha-RAS oncogen in stromal cells and their contribution to the generation and progression of cervical squamous neoplasia has not yet been reported. The aim of this study was detect and determine the frequency of mutations Ha-RAS in stromal fibroblasts from biopsies of the transformation zone of the uterine cervix. We selected eight samples of fresh frozen tissue of patients diagnosed with cervical intraepithelial neoplasia squamous (CIN I, CIN II, CIN III), cancer in situ and invasive squamous cell carcinoma, tissue in which it was represented only the stroma, without evidence of residual tumoral epithelial component, and each of whom had cervical tissue in paraffin-embedded control confirming the presence of cervical squamous neoplasia. The detection of Ha-ras mutations in codon 12 was performed using a nonradioactive PCR-SSCP and restriction enzyme analysis. The mutation found for a substitution of a glycine by a valine at codon 12 of Ha-RAS was detected in alone sample (12.5%), CIN III. The non-detection of the GTC mutation in the remaining seven samples could be due to somatic mutation that this represented only a small fraction (approximately 15%) of total DNA analyzed (33), as well as a topographical heterogeneity likely distribution of these mutations. The presence of a point mutation of Ha-RAS oncogene in the stroma of one case studied, represents an important change, this mutation prevents the conversion of active to inactive form, and suggest an alternative pathway involving stromal genetic instability in the generation of intraepithelial neoplasia and progression of the cervical cancer. Citation Information: Cancer Prev Res 2010;3(1 Suppl):B61.