ABSTRACT
El artículo presenta una revisión de las investigaciones realizadas a la fecha en Colombia relacionadas con la aplicación de los análisis de isótopos en la identificación humana. En especial, hace énfasis en la utilidad de las relaciones isotópicas de estroncio (87Sr/86Sr) para rastrear el lugar de origen de un cuerpo en condición no identificada (CNI). Dentro de la revisión se resalta la importancia de la variabilidad geológica colombiana, la cual puede incidir en la diversidad del estroncio biodisponible, en un espacio y un periodo determinados. Esta diversidad del estroncio biodisponible puede verse reflejada en la distribución espacial de la composición isotópica de estroncio en diferentes tejidos humanos (dientes, huesos, cabello y uñas) de los pobladores del territorio colombiano. Esto es debido a la transferencia de la señal isotópica del estroncio biodisponible a los tejidos humanos. Dentro de las conclusiones de la revisión bibliográfica realizada se menciona la importancia del uso del estroncio (Sr) en la identificación humana en el contexto colombiano, su aplicación forense y sus posibles limitantes respecto al uso de esta metodología en el país.
Subject(s)
Calcium Isotopes , Victims Identification , Forensic MedicineABSTRACT
Potassium depolarization of cultured muscle cells was employed to study cellular responses linked to calcium signaling. Events occurring after depolarization include i) A transient increase of the IP3 mass (2-10s); ii) A slow calcium transient (5 to 25s) that propagates as a low concentration wave along the myotube showing a distinct calcium transient at the level of cell nuclei. Due to the presence of IP3 receptors both in the SR (A-band region) and in the nuclear envelope, these two events appear to be related; iii) Phosphorylation of mitogen activated kinases (ERK 1/2) and of the transcription factor CREB (30 s-10 min), as well as expression of the early genes c-fos, c-jun and egr-1 mRNA (5-15 min). Several independent pieces of evidence, including results obtained using inhibitors specific for individual steps, allowed us to connect these in a sequential manner. As the same type of signaling cascade can be triggered by oxidants, neurotransmitters and hormones, the ensemble of results allows us to propose a general model to describe signaling events that link membrane stimulation to regulation of gene transcription in skeletal muscle cells
Subject(s)
Humans , Animals , Calcium Channels , Calcium Signaling , Gene Expression Regulation , Muscle, Skeletal , Calcium , Calcium Channels , Calcium Isotopes , Cells, Cultured , Cyclic AMP Response Element-Binding Protein , RNA, Messenger , Ryanodine Receptor Calcium Release Channel , Transcription, GeneticABSTRACT
1. Brain micro-slices from guinea pig, mouse and rat were incubated in Krebs-Ringer Na- HEPES buffered medium containing [32P]-phosphate and characterized by immunoblotting with polyclonal antibody to glial fibrillary acidic protein (GFAP). 2. GFAP presented small differences in two-dimensional electrophoretic mobility. 3. The phosphorylation of GFAP was dependent on Ca2+ in the incubation medium in adult animals. 4. Both the immunocontent and level of phosphorylation of GFAP were higher in hippocampus than in cerebral cortex of all the three species