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Rey-Suarez P.,University of Antioquia | Nunez V.,University of Antioquia | Saldarriaga-Cordoba M.,Ibero-American University of Science and Technology of Chile | Saldarriaga-Cordoba M.,Bernardo O'Higgins University | Lomonte B.,University of Costa Rica
Biochimie | Year: 2017

Snake venom phospholipases A2(PLA2) share high sequence identities and a conserved structural scaffold, but show important functional differences. Only a few PLA2s have been purified and characterized from coral snake (Micrurus spp.) venoms, and their role in envenomation remains largely unknown. In this report, we describe the isolation, sequencing and partial functional characterization of two Micrurus PLA2s: MmipPLA2from Micrurus mipartitus and MdumPLA2from Micrurus dumerilii, two species of clinical importance in Colombia. MmipPLA2consisted of 119 amino acid residues with a predicted pI of 8.4, whereas MdumPLA2consisted of 117 residues with a pI of 5.6. Both PLA2s showed the conserved 'group I' cysteine pattern and were enzymatically active, although MdumPLA2had higher activity. The two enzymes differed notably in their toxicity, with MmipPLA2being highly lethal to mice and mildly myotoxic, whereas MdumPLA2was not lethal (up to 3 μg/g body weight) but strongly myotoxic. MdumPLA2displayed higher anticoagulant activity than MmipPLA2in vitro and caused more sustained edema in the mouse footpad assay. Neither of these enzymes was cytolytic to cultured skeletal muscle C2C12 myotubes. Based on their structural differences, the two enzymes were placed in separate lineages in a partial phylogeny of Micrurus venom PLA2s and this classification agreed with their divergent biological activities. Overall, these findings highlight the structural and functional diversity of Micrurus venom PLA2s. © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM)


Sanchez R.C.,Ibero-American University of Science and Technology of Chile | Obregon E.B.,University of Chile | Rauco M.R.,University of Chile
International Journal of Morphology | Year: 2011

Vertebral Column Deformity (VCD) is a common pathology in Chilean salmon farms, lowering the quality and commercialization of the product. Hypoxia has been related to other musculoskeletal deformities, but not to VCD. This work analyzes the morphology of the vertebral column of Salmo salar alevins, cultured under hypoxic conditions (60% O2 saturation in the water tanks) for different time periods after hatching (2, 4, 6 and 8 days). They are compared with their normoxic controls (100% O2 saturation). Using histological (H/E), and morphometric techniques, it was found that the time of exposure to hypoxia is inversely proportional to the body length, notochordal diameter and thickness of its sheath. The organic response to hypoxia was quantified by immunohistochemistry for HIF-1a as the sensor of hypoxia. Its expression increased significantly (p<0.05) in the experimental groups that exhibit VCD. Although etiology for VCD is probably multifactorial, this study allows for the conclusion that hypoxia by itself, produces VCD.


Moya S.A.,University of Santiago de Chile | Araya J.C.,Ibero-American University of Science and Technology of Chile | Gajardo J.,Ibero-American University of Science and Technology of Chile | Guerchais V.,CNRS Chemistry Institute of Rennes | And 3 more authors.
Inorganic Chemistry Communications | Year: 2013

A series of novel complexes of the Ru(L)2(CO)2 L = 2-(3′ methoxyphenyl)-1,8-naphthyridine (complex 1), and type Ru(acac) 2(L)(CO) with L = 2-(3′ methoxyphenyl)-1,8-naphthyridine (complex 2), 2-(2′-bromophenyl)-1,8-naphthyridine (complex 3) and 2-phenyl-1,8-naphthyridine (complex 4) was synthesized and characterized. We found that the complexes 2, 3, and 4 can be directly synthesized from Ru 3(CO)12. The complex Ru(acac)2(L)(CO) L = 2-(3′ methoxyphenyl)-1,8-naphthyridine (2) was characterized by X-ray single crystal analysis which confirms the monodentate coordination mode of the 1,8-naphthyridine derivate and the cis arrangement of the acac ligands. Preliminary studies in transfer hydrogenation of acetophenone in the presence of 2-propanol show the good catalytic activity of complex 2 with 92% conversion. © 2012 Elsevier B.V. All rights reserved.


Bustos-Obregon E.,University of Chile | Castro-Sanchez R.,Ibero-American University of Science and Technology of Chile | Ramos-Gonzalez B.,Autonomous University of Nuevo León | Torres-Diaz L.,University of Valparaíso
International Journal of Morphology | Year: 2010

At present it is not clear if male fertility is affected by intermittent hypobaric hypoxia (IHH). This is an important issue since a large human population works over 3000 masl. This study analyzes testicular changes in adult Sprague Dawley rats after five cycles of IHH (7 day exposure to 4200 masl in a hypobaric chamber / 7 day at 500 masl). The animals were separated into groups of 8, one group was exposed to hypoxia (7 days), and the others to IHH for one to five cycles. Controls (500 masl) were examined at the beginning and at the end of the 70 experimental days. A duplicate set of rats treated with melatonin (supposedly protecting from hypoxia) was also examined, as were their controls, injected with 0,03% ethanol (melatonin solvent).Immunohistochemical and histometric analysis of testicular tissue were performed. Damage caused by IHH increases with time. Morphometry reveals an increase in tubular and luminal diameters and a reduction in epithelial height. Inmunohistochemistry for HIF-1alpha shows an increase with time, however the opposite happens with HSP-70. Spermatogenic cells submitted to comet assay present an increase of (+) cells. Melatonin counteracts all this damage, possibly due to its high efficiency as a reactive oxygen species scavenger. In conclusion, IHH exposure damages male reproductive function.


Gonzalez C.R.,Metropolitan University of Educational Sciences | Llanos L.,Ibero-American University of Science and Technology of Chile | Saldarriaga-Cordoba M.,Ibero-American University of Science and Technology of Chile
Neotropical Entomology | Year: 2016

The terrestrial larva of the austral horsefly, Parosca latipalpis (Macquart), identified by molecular techniques, is described. The larva of P. latipalpis resembles Scaptia auriflua (Donovan), Copidapha vicina (Taylor), Myioscaptia muscula (English), and Osca lata (Guérin-Meneville) in many morphological characters, as well as in their terrestrial habitats. Some characters that are shared between these species are unique among Tabanidae and provide evidence of their monophyletic origin, suggesting a typical Gondwanaland group. Larvae of P. latipalpis were found 2–3 cm below of the soil surface and associated with larvae of Coleoptera, Lepidoptera, and Diptera in southern Chile. © 2016, Sociedade Entomológica do Brasil.


Illanes G.,Ibero-American University of Science and Technology of Chile | Espinoza C.,Ibero-American University of Science and Technology of Chile | Escarate P.,Ibero-American University of Science and Technology of Chile
International Journal of Morphology | Year: 2015

Ultrasound is one of the most widely used methods for gestational diagnosis, allowing the detection of early pregnancy and evaluation of fetal growth and development. Ten pregnant cats (aged 10 months to-6 years) were used in this study, with known dates of mating. Serial ultrasound testings were performed on days 15th (stage 1), 18th (stage 2), 21st (stage 3), 38th (stage 4) and 45th (stage 5) of gestation, to measure biometric parameters (Chorionic vesicle: transverse diameter (DTVC), longitudinal diameter (DLVC); Placenta: thickness (GP); Fetus: cephalocaudal length (LCC), thoraco-abdominal diameter (DTA), cephalic diameter (DC). Photographic records were made at each stage. In stage 1, it was impossible to visualize the embryo. In stage 2, the embryo was observed near the wall measuring 4.7 mm on average LCC, and the endocardial tube was functioning. In stage 3, the umbilical cord was observed, but it was difficult to distinguish different organs, with the exception of the heart, which was detected by heartbeat movements. In stage 4, the fetus begins to move. Organs, such as the brain, lungs, heart septation, diaphragm, liver, stomach, bowel, bladder and bone ossification were observed. In the forelimbs, fingers apart with claws and footpads were visualized. In stage 5, in addition to the features observed in the previous stage, the kidneys show the cortex and medulla, and the heart chambers are clearly visualize. A linear correlation analysis among the biometric parameters was performed. Results were statistically significant for most parameters studied (p<0.0001). We characterized the gestational stages studied. Out of the ten cats studied, seven cats had a normal pregnancy. One cat showed one congenitally malformed fetus, and one fetal death occurred in the other two cats. © 2015, Universidad de la Frontera. All rights reserved.


Estrada-Gomez S.,University of Antioquia | Vargas Munoz L.J.,Co-operative University of Colombia | Saldarriaga-Cordoba M.,Ibero-American University of Science and Technology of Chile | Quintana Castillo J.C.,Co-operative University of Colombia
Acta Tropica | Year: 2016

We report the first biochemical, biological, pharmacological and partial proteomic characterization studies of the Opisthancanthus elatus venom (Gervais, 1844) from Colombia. The Reverse Phase High-Performance Liquid Chromatography venom profile showed 28 main well-defined peaks, most eluting between 20 and 45min (18-30% of acetonitrile, respectively). High-resolution mass analysis indicates the presence of 106 components ranging from 806.59742Da to 16849.4139Da. O. elatus venom showed hemolytic activity and hydrolyzed the specific substrate BapNa suggesting the presence of proteins with serine-protease activity. Collected RP-HPLC fractions eluting at 52.6, 55.5, 55.8, 56.2, and 63.9min (PLA2 region between 33 and 40% of acetonitrile), showed hemolytic activity and hydrolyzed the synthetic substrate 4-nitro-3-octanoyloxy-benzoic acid, indicating the presence of compounds with phospholipases A2 activity. These RP-HPLC fractions, showed molecular masses values up to 13978.19546Da, corroborating the possible presence of the mentioned enzymes. Tryptic digestion and MS/MS analysis showed the presence of a phospholipase like fragment, similar to on described in other Opisthacanthus genus studies. No coagulant activity was observed. No larvicidal or antimicrobial activity was observed at concentrations evaluated. Lethal and toxic activity is expected at doses above 100mg/kg, no neurotoxic effects were detected at lower doses. In conclusion, O. elatus exhibits a venom with a predominant phospholipase A2 activity than thought; mammal's neurotoxic activity is expected above the 100mg/kg, which is very high compared to the venom from other neurotoxic scorpions. © 2015 Elsevier B.V.


Llanos L.,Ibero-American University of Science and Technology of Chile | Gonzalez C.R.,University of Santiago de Chile | Saldarriaga-Cordoba M.,Ibero-American University of Science and Technology of Chile
Zootaxa | Year: 2015

The New World species of the genus Pelecorhynchus Macquart, all of which are only known from Chile, are revised. Two new species are described, Pelecorhynchus hualqui sp. nov. and Pelecorhynchus toltensis sp. nov. All nine New World species in the genus are redescribed and illustrated, and a key to the species is provided. Copyright © 2015 Magnolia Press.


PubMed | Ibero-American University of Science and Technology of Chile, Co-operative University of Colombia and University of Antioquia
Type: | Journal: Acta tropica | Year: 2015

We report the first biochemical, biological, pharmacological and partial proteomic characterization studies of the Opisthancanthus elatus venom (Gervais, 1844) from Colombia. The Reverse Phase High-Performance Liquid Chromatography venom profile showed 28 main well-defined peaks, most eluting between 20 and 45min (18-30% of acetonitrile, respectively). High-resolution mass analysis indicates the presence of 106 components ranging from 806.59742Da to 16849.4139Da. O. elatus venom showed hemolytic activity and hydrolyzed the specific substrate BapNa suggesting the presence of proteins with serine-protease activity. Collected RP-HPLC fractions eluting at 52.6, 55.5, 55.8, 56.2, and 63.9min (PLA2 region between 33 and 40% of acetonitrile), showed hemolytic activity and hydrolyzed the synthetic substrate 4-nitro-3-octanoyloxy-benzoic acid, indicating the presence of compounds with phospholipases A2 activity. These RP-HPLC fractions, showed molecular masses values up to 13978.19546Da, corroborating the possible presence of the mentioned enzymes. Tryptic digestion and MS/MS analysis showed the presence of a phospholipase like fragment, similar to on described in other Opisthacanthus genus studies. No coagulant activity was observed. No larvicidal or antimicrobial activity was observed at concentrations evaluated. Lethal and toxic activity is expected at doses above 100mg/kg, no neurotoxic effects were detected at lower doses. In conclusion, O. elatus exhibits a venom with a predominant phospholipase A2 activity than thought; mammals neurotoxic activity is expected above the 100mg/kg, which is very high compared to the venom from other neurotoxic scorpions.


PubMed | Ibero-American University of Science and Technology of Chile and Metropolitan University of Educational Sciences
Type: Journal Article | Journal: Neotropical entomology | Year: 2016

The terrestrial larva of the austral horsefly, Parosca latipalpis (Macquart), identified by molecular techniques, is described. The larva of P. latipalpis resembles Scaptia auriflua (Donovan), Copidapha vicina (Taylor), Myioscaptia muscula (English), and Osca lata (Gurin-Meneville) in many morphological characters, as well as in their terrestrial habitats. Some characters that are shared between these species are unique among Tabanidae and provide evidence of their monophyletic origin, suggesting a typical Gondwanaland group. Larvae of P. latipalpis were found 2-3cm below of the soil surface and associated with larvae of Coleoptera, Lepidoptera, and Diptera in southern Chile.

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