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Ramon Castilla, Peru

The evidence supports the hypothesis of the cancer stem cells, which postulate that they are responsible for the initiation, the recurrence, metastasis and the resistance to anti neoplasia treatments, creating the need for therapies aimed specifically at these subpopulations of cells with characteristics of stem cells within the most heterogeneous malignant tumors. Within tumors subsets of the cells transformed in neoplasia show the expression on its surface of molecules that are not typically present on the surface of the surrounding normal cells. In some cases, especially in the malignant melanomas, the lymphocytes T cytotoxic directed against these antigens associated with tumors have been isolated to create antibodies and somehow reduce the disease. The approach to vaccine against cancer therapy is based on the idea that the immune system could saddle a rejection response force against the conglomerate of the cells transformed neoplasia. The new markers that are safe and allow direct immunotherapy for eradication of the tumor, with the combination of many therapies, and thus have an efficient outcome in the treatment of this disease is currently looking for. Source

Mejia C.R.,Asociacion Medica de Investigacion y Servicios en Salud | Mejia C.R.,Ricardo Palma University | Quinones-Laveriano D.M.,Ricardo Palma University | Espinoza K.G.,Ricardo Palma University | Quezada-Osoria C.,National University of Piura
Revista Peruana de Medicina Experimental y Salud Publica

The aim of this study was to describe the concentration of lead in umbilical cord blood (UCB) of neonates born from primiparous women who live in northern Lima. A cross sectional study was carried out at Cayetano Heredia National Hospital, from July 2011 to January 2012. 100 neonates born from primiparous women who lived in northern Lima in the previous 5 years or more were included. Umbilical cord lead levels were measured by the atomic adsorption method, and the demographic information and risk factors of the neonates were filled in a patient record designed to this purpose. 30% of the neonates had concentration of lead in UCB that was considered as increased risk (≥ 3,0 μg/dL), 16% of the cases had had toxic concentration of lead in UCB (≥ 5 μg/dL). We conclude that there are a high percentage of neonates contaminated with lead in the northern Lima. Source

Tume-Farfan L.F.,National University of Piura
Gaceta Mexicana de Oncologia

The cells acquire different patterns of gene expression during differentiation to adapt to a changing environment. Epigenetic and genetic alterations are considered to be 2 independent mechanisms involved in the onset and progression of cancer. Epigenetic mechanisms may be important for biological events such as the genetic mechanisms that do not involve a change in DNA sequence, but if they have an important role in modifying gene expression. During the last decade, research in epigenetic alterations in cancer progression has been improved thanks to the emergence of new technologies, to find applications in the diagnosis and therapy of this disease. In this review is discussed the current evidence on the role of epigenetic mechanisms in the progression of various cancers highlighting the advantages of the investigation of epigenetics in future new treatments. 1665-9201 © 2014 Gaceta Mexicana de Oncología. Publicado por Masson Doyma México S.A. Todos los derechos reservados. Source

Tume Farfan L.F.,National University of Piura | Tume Farfan L.F.,Laboratorio Of Biotecnologia Molecular
Revista Venezolana de Oncologia

We know that our cells have gene expression patterns that can be on altered over and give rise lead to cancer. The epigenetic is the study of the changes in the gene expression without modifying the DNA sequence. The epigenetic and the genetic alterations are considered as two separate mechanisms involved in the onset and progression of the cancer. During the last decade have emphasized the field of the epigenetics to find applications in the diagnosis and therapy in this disease, along with microRNAs play an important role in the silencing of certain genes against certain conditions. In this review, we study and discussed the epigenetic changes and microRNAs that are notorious in the lung cancer and the importance of both in the early diagnosis of this disease and his therapy they are discussed. © 2015, Sociedad Venezolana de Oncologia. All rights reserved. Source

Manchester S.R.,University of Florida | Herrera F.,University of Florida | Herrera F.,Smithsonian Tropical Research Institute | Fourtanier E.,California Academy of Sciences | And 2 more authors.
Journal of Geology

The Belén flora, in north coastal Peru, is the most diverse fruit and seed assemblage yet known from the Paleogene of South America. Little original paleobotanical work has been performed on this assemblage since the pioneering treatments published by E. W. Berry in the 1920s, and the precise age has not been determined. Nevertheless, the flora has been regarded as a focal point in understanding the vegetational, orogenic, and climatic history of northern South America, and in recent literature it has been assumed to be early Eocene. In order to tighten this age assignment, which has varied from early Eocene to early Oligocene in the opinions of different authors, we revisited the Belén site, measured the stratigraphic section, and processed the fruit- and seed-containing sediment for age-diagnostic microfossils. Although pollen and foraminifera were not recovered, the sediment is rich in diatoms. The diatom assemblage includes Lisitzinia ornata and Rocella vigilans, among others, indicating a latest early Oligocene age (~30-28.5 Ma) for these deeper marine sediments, which we infer to have been subsequently reworked into the Belén environment. We also reevaluate the botanical identifications, which are based on the original museum specimens supplemented by more recently collected specimens. The Belén flora provides a window into extinct forests in South America that were present before the rising of the Andes in western Peru. © 2012 by The University of Chicago. Source

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