Seminario de Vinculación
Lunes 6 de diciembre, 2010
9:00-10:15 |
Biomolecular Computing for the Treatment of Liver Cirrhosis Ricardo Strauss |
10:15-11:30 |
Biomarkers Associated with H. Pylori in Early Gastric Cancer Gonzalo Castillo Rojas, Yolanda López Vidal
Gastric cancer is considered one of the most frequent malignancies, often associated to H. pylori. The presence of this microrganism induces alterations in the transduction processes that affect the genetic expression in gastric epithelial cells, through the over-expression of oncogenes, the inactivation of the expression of suppressor genes or those involved in DNA repair. Those events give place to apoptosis, alterations in the cell cycle and death cells that allow for the development of a cancer . These alterations can originate in any site of the cell so we hypothesize that determining the genetic expression of RAS, c-myc, p53, APC, HMLH1, HER-2, FHL2 y hTERT associated to the presence of H. pylori and its virulent factors in gastric biopsies could allow the association of diverse genetic profiles as potential biomarkers with diagnostic and prognostic value for the early identification of subjects with high risk for gastric cancer. We will use real time PCR with fluorescent Taq Man. For the positive control we will use RNA from AGS cells. Cellular damage will be determined through micronuclear assays and comet assay; apoptosis will be evaluated by TUNEL y anexin V. To determine the presence of H Pylori in the biopsies we will amplify the 16S RNAr gene, the characterization of the variable region 3’ of the gene cagA assessed by PCR, and the typification of the vacA. Mutations will be identified through a conformational analysis of reference chains (RSCA).
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11:30-12:45 |
Calorimetric Analysis as an Alternative for Liver Fibrosis Diagnosis Galileo Escobedo
Liver fibrosis/cirrhosis leads to local accumulation of extracellular matrix proteins including type I and III collagen. This compositional change triggers the alteration of liver structure and blood circulation, as well as modification in the serum level of hepatic metabolism-related proteins. Calorimetry is an experimental tool able to determine the accurate molecular composition of any organic material based on the analysis of thermal properties such as heat capacity, heat flow and transition temperature. Taking into account that fibrosis guide to compositional variations locally in the liver and also peripherally at the blood stream, we propose that we will be able to distinguish between both serum and liver samples from healthy and fibrotic patients by using a calorimetric approach. For that purpose, by means of modulated scanning calorimetry we will analyze the heat capacity, heat flow and transition temperature in 450 serum samples, and their corresponding liver specimens, from patients with F1, F2, F3 and F4 liver fibrosis of several etiologies, previously diagnosed by liver biopsy valuation. Serum and liver samples with no fibrosis (F0) will be obtained from healthy liver donors. Furthermore, all serum and liver specimens will be assessed by means of bidimensional electrophoresis in order to determine the specific proteomic pattern associated to mild, moderate and severe human liver fibrosis, through which we will separately analyze the heat capacity, heat flow and transition temperature in those proteins showing the highest variation level related to every stage of liver damage. Our preliminary results suggest that heat capacity,heat flow and transition temperatures from sera and liver of fibrotic rats are significantly different from those found in normal healthy animals, even at the initial stage of the pathology
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12:45-13:45 |
Lunch |
13:45-15:00 |
Balance Assesment Using a Force Plataform Clara Garza, Arturo Olvera, Ulises Perez
Force plataforms provide critical data for biomechanical analysis because they measure the interaction between the subject and the environment. The purpose of this work is to find a simple and inexpensive way to assess stability and level of sway in elderly people to try to predict and prevent falls.
We are testing the suitability of the Wii Balance Board for this purpose. The platform is connected via bluetooth to a computer and the information from the four sensors of the platform is analyzed in time and frequency domains. The results are being compared with the traditional tests performed by geriatricians.We are also working on a mathematical model to understand the results. |
15:00-16:15 |
Hematopoietic Stem Cells as a Source of Sinusoidal Endothelial Cells Joselin Hernandez
Liver fibrosis is characterized by capillarization with loss of fenestration in sinusoidal endothelial cells (SEC) and collagenization of the Disse space. Restoration of fenestration has proved to avoid or revert liver fibrosis. Maintenance of SEC phenotype induces quiescence of stellate cells and proliferation of hepatocytes. Currently, SEC are obtained from hepatic tissue as mature SEC and there is not an option to obtain autologous SEC from cirrhotic livers. We propose to use hematopoietic stem cells ( CD34 and CD 133) as a source of SEC in vitro through VEGF and misalkolkine in culture condition of shear stress over a nanotechnology constructed scaffold complemented with the necessary factors for differentiation and maintenance of an adequate phenotype for its eventual transplantation.
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