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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. Source

Morales M.A.,University of Chile | Ahumada F.,Ibero-American University of Science and Technology of Chile | Castillo E.,Austral University of Chile | Burgos R.,Austral University of Chile | And 3 more authors.
Zeitschrift fur Naturforschung - Section C Journal of Biosciences | Year: 2013

The relative lack of specificity of atropine as a competitive antagonist of muscarinic receptors is a frequent cause of undesirable parasympathetic side effects. Consequently, new tropane alkaloids with potentially greater selectivity are usually seen with real interest. The cholinergic antagonistic effects of a purified mixture of tropane alkaloids extracted from Schizanthus hookeri were evaluated in rat ileum. For this purpose, ileal segments were obtained from randomly selected male Sprague-Dawley rats, and the effect of 1 · 10-4, 1 · 10-3, and 1 · 10-2 mg/mL of the purified mixture of alkaloids on the contractile response of the ileum induced with increasing doses of carbachol (5 · 10-8 - 8 · 10-4 M) was determined. The results were compared with those obtained in the presence of 3.46 · 10-7, 3.46 · 10-6, and 3.46 · 10-5 mg/mL atropine as an agonist. Tropane alkaloids extracted from Schizanthus hookeri competitively antagonized acetylcholine muscarinic receptors. © 2013 Verlag der Zeitschrift für Naturforschung, Tübingen. Source

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. Source

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 Leon | Torres-Diaz L.,University of Valparaiso
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. Source

Gonzalez C.R.,Metropolitan University of Educational Sciences | Gonzalez C.R.,Institute Salud Publica Of Chile | Reyes C.,Institute Salud Publica Of Chile | Rada V.,Ibero-American University of Science and Technology of Chile
Zootaxa | Year: 2015

Male and female adults of Culex (Culex) articularis Philippi are redescribed, and the 4th-instar larva and pupa are described and illustrated for the first time. Culex articularis is compared with other species of the subgenus Culex. Illustrations of diagnostic characters of the female, male genitalia, 4th-instar larva, and pupa are also provided. Copyright © 2015 Magnolia Press. Source

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