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1.
Fish Physiol Biochem ; 48(6): 1449-1462, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36480096

RESUMEN

The objective of this work was to develop a food additive for the sex reversal of Nile tilapia (Oreochromis niloticus) based on a simple oil in water (O/W) nanoemulsion with testosterone propionate for incorporation into commercial feed. Oil screening and evaluation of the organoleptic and physicochemical characteristics were carried out to determine the best formulation. A palatability test was also performed. Sex reversal test was assayed using 5 experimental groups: negative control - macerated feed without hormone; free testosterone - macerated feed with 60 mg/kg of testosterone propionate diluted in ethanol; and macerated feed with testosterone propionate nanoemulsion at a concentration of 30, 60, and 90 mg/kg. Stable nanoemulsions (size 76-210 nm) with testosterone propionate were produced. All nanoemulsion-added feed was palatable to tilapia. We obtained sex reversal values of ≈65, 75, and 72% in the groups of 30, 60, and 90 mg/kg, respectively. We can conclude that the nanoemulsion showed promising results; it is capable of inducing sex reversal in tilapia, is suitable as a commercial product, and has the potential to promote safety for rural staff and reduce the environmental impact of hormones.


Asunto(s)
Cíclidos , Propionato de Testosterona , Tilapia , Animales , Testosterona , Alimentación Animal
2.
Fish Physiol Biochem ; 45(3): 1177-1187, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30941630

RESUMEN

The toxic effects of thyroxine (T4F), levothyroxine (L-T4), and thyroxine complexed into ß-cyclodextrin (ß-CD-T4) on the biological parameters of tambaqui (Colossoma macropomum) were evaluated. The animals were exposed to a chronic toxicity test based on concentrations of influent (60 ng/L) for 2 months. Weight, total length, animal behavior, oxygen consumption, photopic electroretinogram (ERG), and the Flicker exam were evaluated. No significant differences were observed (p > 0.05) on the weight and total length measurements between all groups studied. Behavioral observations of the animals exposed to L-T4 and ß-CD-T4 complex showed a reduction (p < 0.05) in slow swimming and an increase in staying motionless events. The animals exposed to the ß-CD-T4 complex presented the highest O2 consumption. L-T4 and ß-CD-T4 promoted a reduction in the ability of the animals to respond to stimuli in the photoreceptors according to the photopic ERG examination. Data from the experimental Flicker exam showed no significant differences (p > 0.05) in all groups studied. It can be concluded that the complexation of T4 into ß-CD and L-T4 modified the toxicity of this hormone, promoting changes in the behavior, oxygen consumption, and electrophysiological responses of the exposed animals, suggesting that inclusion complexes should be submitted to new toxicity tests to ensure higher safety.


Asunto(s)
Conducta Animal/efectos de los fármacos , Characiformes , Ciclodextrinas/química , Electrorretinografía/veterinaria , Consumo de Oxígeno/efectos de los fármacos , Tiroxina/toxicidad , Animales , Esquema de Medicación , Tiroxina/administración & dosificación , Pruebas de Toxicidad
3.
Curr Diabetes Rev ; 13(6): 566-572, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27324876

RESUMEN

INTRODUCTION: Diabetes Mellitus (DM) is a chronic hyperglycemic condition with major health concern on a global scale. DM is a heterogeneous metabolic disorder stemming from defective insulin secretion and/or resistance to action of insulin. Diabetes is recognized cause of male sexual dysfunction and affects reproductive function in humans and animal models, including the endocrine control of spermatogenesis, erectile dysfunction and ejaculation disorder. Testicular disorder is characteristically marked by reductions of testicle weight, sperm count and motility, as well as changes in the morphology of the seminiferous epithelium. Altered testosterone level is another characteristic of diabetic animals. Studies have demonstrated that DM increases apoptosis in germ cells and lead to the interruption of spermatogenesis, mainly by exerting an influence on Bcl-2 protein and cysteinedependent aspartate-directed proteases. DM also increases oxidative stress in testicular cells and excessive production of radical oxygen species has been demonstrated. Several strategies can be used as means of prevention and/or treatment for diverse types of damage to testicles by DM such as regular physical exercise, stress reduction and food intake of substances with antioxidant potential. A hypoglycemic and antioxidant potential diet, in particular, the seafood, can be a valuable instrument of guard against damage caused by DM, both the systemic level as testicular level. The objective of this review is to summarize evidences that study the antioxidant, anti-inflammatory and anti-apoptosis role of seafood in testicles morphology damages induced by diabetes mellitus. CONCLUSION: The seafood plays an antioxidant, anti-inflammatory and anti-apoptosis role in testicles morphology damages induced by diabetes mellitus. This relation seems to be associated with Omega-3 and carotenoids (astaxanthin) levels.


Asunto(s)
Antioxidantes/uso terapéutico , Complicaciones de la Diabetes/fisiopatología , Dieta , Alimentos Marinos , Enfermedades Testiculares/prevención & control , Enfermedades Testiculares/fisiopatología , Animales , Apoptosis , Diabetes Mellitus Experimental/complicaciones , Disfunción Eréctil/etiología , Humanos , Masculino , Estrés Oxidativo , Espermatozoides/metabolismo , Enfermedades Testiculares/etiología , Testículo/fisiopatología
4.
J Cancer ; 5(2): 143-50, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24563668

RESUMEN

Natural products contain important combinations of ingredients, which may to some extent help to modulate the effects produced by oxidation substrates in biological systems. It is known that substances capable of modulating the action of these oxidants on tissue may be important allies in the control of neovascularization in pathological processes. The aim of this study was to evaluate the antioxidant and antiangiogenic properties of an ethanol extract of Caesalpinia echinata. The evaluation of antioxidant properties was tested using two methods (DPPH inhibition and sequestration of nitric oxide). The antiangiogenic properties were evaluated using the inflammatory angiogenesis model in the corneas of rats. The extract of C. echinata demonstrated a high capacity to inhibit free radicals, with IC50 equal to 42.404 µg/mL for the DPPH test and 234.2 µg/mL for nitric oxide. Moreover, it showed itself capable of inhibiting the inflammatory angiogenic response by 77.49%. These data suggest that biochemical components belonging to the extract of C. echinata interfere in mechanisms that control the angiogenic process, mediated by substrates belonging to the arachidonic acid cascade, although the data described above also suggest that the NO buffer may contribute to some extent to the reduction in the angiogenic response.

5.
Zootaxa ; 3636: 421-38, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26042302

RESUMEN

We report the discovery of a new species of Coendou (Rodentia, Erethizontidae), here designated Coendou speratus sp. nov. This small porcupine, locally known as coandumirim, is found in the Pernambuco Endemism Centre in the Atlantic coast of northeastern Brazil north of the São Francisco river, one of the most important known biodiversity hotspots. The geographic range of C. speratus overlaps with that of the larger, widespread C. prehensilis, but not with that of C. insidiosus from the southeastern Atlantic forest, nor with that of C. nycthemera, an eastern Amazonian species. Coendou speratus is a small-bodied, long-tailed species that appears to be completely spiny because it lacks long dorsal fur. The dorsal quills have conspicuously brownish red tips that contrast with the blackish dorsal background color. The new species is overall similar to C. nycthemera, but the dorsal body quills are typically tricolored in the former and bicolored in the latter. The new species is externally very distinct from C. insidiosus, especially because the latter has bicolored dorsal quills that are almost completely hidden beneath longer and homogeneous pale or dark hairs.


Asunto(s)
Puercoespines/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Brasil , Femenino , Bosques , Masculino , Datos de Secuencia Molecular , Tamaño de los Órganos , Filogenia , Puercoespines/anatomía & histología , Puercoespines/genética , Puercoespines/crecimiento & desarrollo
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