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Perez-Torres A.,National Autonomous University of Mexico | Vera-Aguilera J.,TTUHSC Permian Basin | Sahaza J.H.,Corporacion para Investigaciones Biologicas CIB | Vera-Aguilera C.,National Autonomous University of Mexico | And 4 more authors.
Cancer Biotherapy and Radiopharmaceuticals | Year: 2015

Objective: In a previous study, we demonstrated the therapeutic efficacy of a subcutaneous injection of GK1 peptide in a melanoma mouse model, effectively increasing the mean survival time by 42.58%, delaying tumor growth, and increasing intratumoral necrosis compared with the control. As a first approach to investigate the anti-melanoma effect of GK1, this study was carried out to determine the hematological effects along with both serum and lung cytokine profiles in a melanoma lung metastatic model. Materials and Methods: Thirteen C57BL6 female mice were transfected in the lateral tail vein with 2×105 B16-F0 melanoma cells. After 7 days, mice were separated in two different groups and treatments were initiated (day 0): The GK1-treated group (seven mice) were injected every 5 days intravenously with GK1 (10μg) in the lateral tail vein, and the control group (six mice) were injected every 5 days with intravenous saline solution. Blood samples were collected every 5 days from day 0; tumor samples were obtained for cytokine measurements on the day of sacrifice. Results: In the peripheral blood, mice treated with GK1 presented a statistically significant decrease in IFN-γ (p<0.05), and lymphocytes tended to be lower compared with the control mice (p=0.06). Lung metastatic analysis demonstrated a significant increase in IFN-γ and IL-12p70 (p<0.05); a significant decrease in IL-17, IL-4, IL-22, IL-23, and IL-12p40 (p<0.05); and a marginal decrease in IL-1β (p=0.07) compared with the control. Discussion: Our results suggest that an intratumoral increase of cytokines with antitumor activity along with an intratumoral decrease of cytokines with protumor activity could explain, in part, the anti-melanoma effects of GK1 in a lung metastatic melanoma mouse model. Further studies must be performed to elucidate the precise mechanisms of action for GK1 peptide against melanoma, and their eventual application in humans. © Mary Ann Liebert, Inc. 2015. Source

Garcia S.D.G.,Corporacion para Investigaciones Biologicas CIB | Garcia S.D.G.,University of Antioquia | Lorza A.R.,University of Tolima | Pelaez C.A.,University of Antioquia
Summa Phytopathologica | Year: 2014

Microorganisms for biological control are capable of producing active compounds that inhibit the development of phytopathogens, constituting a promising tool to obtain active principles that could replace synthetic pesticides. This study evaluated the ability of several potential biocontrol microorganisms to produce active extracellular metabolites. In vitro antagonistic capability of 50 bacterial isolates from rhizospheric soils of “criolla” potato (Solanum phureja) was tested through dual culture in this plant with different plant pathogenic fungi and bacteria. Isolates that showed signifcantly higher antagonistic activity were fermented in liquid media and crude extracts from the supernatants had their biological activities assessed by optical density techniques. Inhibitory effect on tested pathogens was observed for concentrations between 0.5% and 1% of crude extracts. There was a correlation between the antimicrobial activity of extracts and the use of nutrient-rich media in bacteria fermentation. Using a bioguided method, a peptidic compound, active against Fusarium oxysporum, was obtained from the 7ANT04 strain (Pyrobaculum sp.). Analysis by nuclear magnetic resonance and liquid chromatography coupled to mass detector evidenced an 11-amino acid compound. Bioinformatic software using raw mass data confrmed the presence of a cyclic peptide conformed by 11 mostly non-standard amino acids. © 2014, Universidade Estadual Paulista (UNESP). All rights reserved. Source

Benavides A.M.,Corporacion para Investigaciones Biologicas CIB | Wolf J.H.D.,University of Amsterdam | Duivenvoorden J.F.,University of Amsterdam
Journal of Tropical Ecology | Year: 2013

The contribution of vegetative recruitment by non-tree species to the regeneration of tropical forests in man-made clearings or tree-fall gaps tends to be ignored. In a series of field studies near Amacayacu, Colombian Amazonia, we tested if hemiepiphytic aroids quickly colonize such open habitats through seed dispersal, sprouting plant fragments, or lateral invasion of flagellar aroids from the closed forest nearby. A seed germination experiment applying two soil substrates and three shade levels showed that abundant light reduced the germination success of three Philodendron species. A total of 400 cuttings from five Philodendron species were placed in forest clearings and almost 12% of these sprouted within 14 wk. Monitoring more than 2000 aroid plants over 14 mo in different habitats showed that recruitment was low (0.3 plants per 10 m 2) compared with initial densities (3.1 plants per 10 m2). Flagellar aroids grew about 2.5 times faster than non-flagellar aroids. In forest edges they reached a mean apical growth of 98 cm in 14 mo. However, non-flagellar aroids were five to six times more abundant than flagellar individuals everywhere. It was concluded that hemiepiphytic aroids colonize open habitats mostly through a post-disturbance survival of plants or plant fragments. Copyright © 2013 Cambridge University Press. Source

Robledo J.A.,Corporacion para Investigaciones Biologicas CIB | Robledo J.A.,Pontifical Bolivarian University | Murillo A.M.,Corporacion para Investigaciones Biologicas CIB | Rouzaud F.,Corporacion para Investigaciones Biologicas CIB
IUBMB Life | Year: 2011

The production of pigments by bacterial colonies has sparked interest among bacteriologists since the 19th century, whether for taxonomy or, in the case of carotenoids for their association with antibiotics resistance. Mycobacteria have gained a very special place in the bacterial world due to their clinical importance. Alone, Mycobacterium tuberculosis is responsible for about two million deaths annually worldwide making tuberculosis one of the most influential diseases in the history of mankind. Almost half of the Nontuberculous Mycobacteria species identified are associated with opportunistic infections in animals and humans. Mycobacterial pigmentary characteristics started to be documented about 80 years ago; but to date, their main use has been only for limited taxonomic and identification purposes. While mycobacterial pigments, especially carotenoids have been clearly associated with cellular photoprotection and survival, the regulation of their production and their physiological role have been largely unstudied. Recent advances in deciphering mycobacterial genomes and characterization of carotenoid synthesis genes, combined with an urgent need for innovative approaches to understand Mycobacterium tuberculosis pathogenic properties open new avenues for exciting research opportunities that might lead to new therapeutic strategies against a devastating secular disease. © 2011 IUBMB. Source

Canteros C.E.,Instituto Nacional Of Enfermedades Infecciosas Inei Anlis Dr Carlos G Malbran | Velez H. A.,Hospital Pablo Tobon Uribe | Velez H. A.,Laboratorios Dinamica | Velez H. A.,Pontifical Bolivarian University | And 6 more authors.
Medical Mycology | Year: 2015

Coccidioides immitis and C. posadasii are the etiologic agents of coccidioidomycosis, an endemic fungal disease of the Americas. In Colombia, this mycosis is uncommon, and only five cases, two of them imported, have been documented. By means of DNA sequencing, C. immitis was identified in formalin-fixed, paraffin-embedded archival tissues samples from the 5th Colombian patient diagnosed in 1997. The patient was born in Pinto, Department of Magdalena, and had never visited other geographic regions, a reason to consider that the mycosis had been acquired locally. This species is primarily found in California although it has been occasionally reported in other geographic areas such as Mexico and Brazil. This is the first indigenous report of C. immitis-associated coccidioidomycosis in a Colombian patient. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. Source

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