Consulta: creatorFacets:"Bustos-Obregón,Eduardo"
Registros recuperados: 20
Data/hora: 10/06/2024 12:21:50

Protective Role of Melatonin in Mouse Spermatogenesis Induced by Sodium Arsenite
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Poblete,Daniel; Catriao,Roberto; Fernandes,Fábio Henrique.
Arsenic is a testicular environmental toxic. Melatonin (Me), being a potent antioxidant, may reduce the damage caused by arsenic in male fertility. The effects of daily oral exposure of Sodium Arsenite (As; 7.0 mg/kg/bw); Melatonin (Me, 10.0 mg/kg/bw); Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw), and Negative Control (NaCl 0.9%) in male CF-1 adult mice were assessed in acute (8.3 days), chronic (33.2 days) and recovery (66,4 days) of testicular damage. We evaluated changes in testicular weight and histopathological, morphometric measurements, expression of COX-2 and Androgen Receptor (AR) antigens and lipid peroxidation levels. Treatment resulted in decreased tubular diameter and AR expression, and increased: interstitial area, luminal diameter, COX-2...
Tipo: Journal article
Palavras-chave: Mouse; Arsenic; COX-2; Androgen receptor; Oxidative stress; Melatonin.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022013000300012

Hermafroditismo Funcional de la Gónada de Fissurella crassa (Mollusca: Fissurellidae)
Provedor de dados: 77
Autores: Olivares Paz,Alberto; Jofré Madariaga,David; Alvarez Mazú,Carlos; Bustos-Obregón,Eduardo.
La costa del Pacífico sudoriental es el hábitat de las 13 especies de lapas descritas del subgénero Fissurella Brugière. En estas especies no existe dimorfismo sexual, los animales son dioicos, el sexo se reconoce explorando directa o indirectamente las gónadas y no tienen procesos de reversión sexual. La presencia de un organismo de Fissurella crassa con gónada formada por porciones de ovario y otras de testículo con capacidad para generar óvulos y espermatozoides, evidencia la potencialidad que los organismos de Fissurella poseen para desarrollar el hermafroditismo funcional. Sin embargo, el presente hallazgo no permite inferir si el agente desencadenante del desarrollo sincrónico funcional de la gónada hermafrodita es un factor endógeno y/o asociado a...
Tipo: Journal article
Palavras-chave: Mollusca; Fissurella crassa; Hermafrodita; Gónada; Gametos.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022009000200034

Boron as Testicular Toxicant in Mice (Mus domesticus)
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Olivares,Christopher.
It has been reported that boron causes changes in various systems, including the male reproductive system. Residents in some towns in northern Chile were consuming a few years ago in the drinking water 20 times more than the amount established as permissible limit by WHO. This study evaluates the effects in an animal model of high intake of boron on the testis. Boron was administered in the drinking water. Twenty male mice (Mus domesticus), sexually mature, were used, divided into 2 groups: the experimental group was given Boron at a dose of 12 mg/L, and the control group 0.6 mg/L, for 42 days. Sections of testis were obtained for: HE staining (Morphometry and Histopathology), Immunohistochemistry (Cox-2), Mallory and Picrosirious stain (evaluation of...
Tipo: Journal article
Palavras-chave: Boron; Mouse; Testicular structure; Collagen I/III; Infertility.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022012000300057

Rat Spermatogenesis Damage in Intermittent Hypobaric Hypoxia and the Protective Role of Melatonin: I Cauda Epididymal Spermatozoa
Provedor de dados: 77
Autores: Hartley,Ricardo; Castro-Sánchez,Rodrigo; Ramos-Gonzalez,Benito; Bustos-Obregón,Eduardo.
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 epididymal sperm, in adult Sprague Dawley rats after five cycles of IHH (7 days exposure to 4200 masl in a hypobaric chamber / 7 days 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). Epididymal...
Tipo: Journal article
Palavras-chave: Sperm quality; Intermittent hypobaric hypoxia; Melatonin protection.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022009000400049

MICE TESTICULAR DAMAGE ELICITED BY MALATHION
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; González-Hormazábal,Patricio.
Organophosphorous pesticides are a healh problem worldwide, mostly for agroworkers, which are around 2600 millions of person in the year 2001. Little is known about male reproductive damage elicited by these chemicals. The acute effects of malathion (single intraperitoneal injection), 1/12 the LD50 to mice were analyzed at 1, 8, 16, 35 and 40 days after injection, in terms of spermatogenic cell proliferation and apoptosis and of Sertoli cell compromise as revealed by immunocytochemical detection of CK-18 (cytokeratin). The micronuclei test was done to assess for genotoxic activity of the agropesticide. The results showed decreased germ cell number followed by compensatory spermatogonial proliferation by 16 days (as shown by thymidine-H3 testicular uptake),...
Tipo: Journal article
Palavras-chave: Spermatogenesis; Organophosphorous agropesticides; Proliferation; Apoptosis.
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022003000200010

Effects of Chronic Simulated Hypobaric Hypoxia on Mouse Spermatogenesis
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Esveile,Christian; Contreras,Julio; Maurer,Inge; Sarabia,Luis.
Reduction of O2 delivery to tissues damage them, including the seminiferous epithelium. Recently, population working in high altitude has increased, so that the study of hypobaric hypoxia on spermatogenesis becomes of interest. In this study we used two groups of male, sexually mature mice Control (C) (540 meters above sea level (masl)) and chronic simulated hypobaric hypoxia (CSHH) (4,600 masl) exposed during 8, 16, 24 or 33 days. Hematocrit; reticulocytosis; testicular, epididymal and seminal vesicle weight; seminiferous epithelium height, tubular diameter, sperm count and morphology and testicular parenchyme and spermatozoa membranes lipoperoxidation were measured. Weight of testis, epididymis and seminal vesicle were reduced but they recuperate at 33...
Tipo: Journal article
Palavras-chave: Hypoxia; Lipoperoxidation; Mouse; Testis.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022006000400030

Rat Spermatogenesis Damage in Intermittent Hypobaric Hypoxia and the Protective Role of Melatonin. II: Testicular Parameters
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Castro-Sánchez,Rodrigo; Ramos-González,Benito; Torres-Díaz,Leandro.
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...
Tipo: Journal article
Palavras-chave: Spermatogenesis; Intermittent hypobaric hypoxia; Melatonin protection.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022010000200034

Melatonin Protective Role in Mouse Cauda Epipidymal Spermatozoa Damage Induced by Sodium Arsenite
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Poblete,Daniel; Catriao,Roberto; del Sol,Mariano; Fernandes,Fábio Henrique.
We evaluated the sperm parameters such as cauda epididymis weight, sperm count, sperm morphology and sperm DNA stability of adult CF-1 male mice treated daily (oral exposure) with the toxic sodium arsenite (As, 7.0 mg/kg/body weight); Melatonin (Me, 10.0 mg/kg/bw), Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw) and Negative Control (NaCl 0.9%) to assess acute (8.3 days), chronic (33.2 days) and recovery of testicular damage (66.4 days). Arsenic decreases the number of sperm from chronic treatment (33.2 days) and this effect continued until 66.4 days of treatment. The toxic effect of As also altered the morphology of spermatozoa in all treatment periods when compared to the negative control group. However, Metalonin induced protective effects in periods of 33.2...
Tipo: Journal article
Palavras-chave: Mouse; Melatonin; Arsenic; Sperm; DNA stability.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022013000400017

Morphometric Analysis of Mice Testicular Tubules after Administration of Malathion and Maca
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; del Río,Fernando Costa; Sarabia,Luis.
Organophosphoric (OP) agropesticidas are amply used to increase food production. However, it has been verified that they induce alterations at testicular level related to the diminution of fertility in humans as in animals. On the other hand, different studies have been made to develop chemical or natural compounds that can induce an antagonistic effect to OP. In previous studies an extract from a plant, from the Peruvian Andes (Maca) has been recognized by its stimulating action on spermatogenesis. In the present study the effects of both external agents were evaluated on testicular sections of testis of adult male mice on a population of 52 mice CF1, divided at random in 4 groups (Control, Malathion, Maca, Malathion-Maca), with sacrifice intervals of...
Tipo: Journal article
Palavras-chave: Testis; Morphometry; Mice; Malathion; Maca.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022007000200001

Effect of Flutamide in Mouse Spermatogenesis and on the Function of Seminal Vesicle and Prostate
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Esponda,Pedro; Sarabia,Luis.
The spermatogenesis is regulated by the hypotalamus-hypophysis gonadal axis, and the androgens play a fundamental role in their last stages. The administration of the antiandrogen flutamide interferes with the function of androgen dependent organs (Prostate (P) and Seminal Vesicle (VS)). In this study flutamide (10mg/Kg b.w.) was injected to 10 mice and vehicle to the controls (n=6). The mice were sacrificed at 24 (n=5) and 72 (n=5) hours. In testicular sections the tubular diameter (TD) and height of seminiferous epithelium (EH) were measured. P and VS were macerated, and concentrations of fructose (VS) and zinc (P) were determined. No significant difference exists in the DT among the groups. However, the 72 hrs group showed EH higher than the control (p...
Tipo: Journal article
Palavras-chave: Flutamide; Mouse; Spermatogenesis; Seminal vesicles; Prostate.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022006000300008

AGEING INDUCES APOPTOSIS AND INCREASES HSP70 STRESS PROTEIN IN THE EPIDIDYMIS OF Octodon degus
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Esponda,Pedro.
Apoptosis has been largely analyzed in the testis. Nevertheless, the epididymis has been scarcely studied. We analyzed the number of apoptotic cells in the different regions (caput, corpus and cauda) of the epididymis of the South American rodent Octodon degus both young and senile. Apoptosis was identified using the TUNEL method which detects in situ DNA fragmentation. Apoptosis was detected in the principal cells of the epididymal epithelium. The caput epididymis was the region more affected. The caput of young animals showed that 0.32/1000 cells were apoptotic in contrast to 5.1/1000 of senile animals. Also in the cauda epididymis apoptosis is increased with age, appearing 0.14/1000 and 3.9/1000 in young and senile animals, respectively. On the other...
Tipo: Journal article
Palavras-chave: Androgens; Apoptosis; Epididymis; Ageing; Heat Shock Proteins.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022004000100005

Histopathological Effects of Boron on Mouse Liver
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Hartley Belmar,Ricardo; Catriao-Gálvez,Roberto.
Boron is a non-metal element, commonly found in Nature as borates in sedimentary rocks, charcoal, oceans and soils. In Chile, it is found in high concentrations in the drinkable water of the XV region, in Arica city, in concentrations that exceed the WHO normative. The present work evaluates the effect of boron at a dose of 12 mg/L of water (equivalent to 0.0686 g of boric acid) given orally for 8,42 and 49 days to 3 experimental groups of 10 mice each. Liver sections were stained with PAS-hematoxyline (to evaluate glycogen), Mallory (to identify collagen fibers) and Picrosirius red with polarizing light to classify collagen fibers. Results indicate that boron evokes diverse effects in liver. Binucleated cells were evaluated and counted and results were...
Tipo: Journal article
Palavras-chave: Boron; Mouse liver; Glycogen Deposition; Collagen quality.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022008000100026

Effect of Methamidophos on the Morphology and Male Reproductive Parameters of the Earthworm Eisenia foetida
Provedor de dados: 77
Autores: Espinoza-Navarro,Omar; Ferreira,Carolina; Bustos-Obregón,Eduardo.
The earthworm Eisenia foetida (Annelida, Oligochaeta) is an excellent biosentinel model organism for assessing potential toxicological risks by xenobiotics in terrestrial ecosystems. Methamidophos is an organophosphorous insecticide widely used to control agricultural pests. Its main action is due to inhibition of the enzyme acetylcholinesterase. The aim of this study was to evaluate the toxicity of methamidophos on the morphology and male parameters in Eisenia foetida. After determining the LD50 for methamidophos (85.34 mg/kg soil), five groups were formed, including control subjects, and sprayed with tap water. Methamidophos treated groups were subjected to doses of 1/10, 1/6, 1/3 and 2/3 of the LD50. Each group was analyzed at day 1, 6, 14 and 30...
Tipo: Journal article
Palavras-chave: Reproduction; Eisenia foetida; Methamidophos; Cytotoxicity.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022013000300051

VARIACIONES DEL FUNCIONAMIENTO TESTICULAR Octopus mimus ADULTOS
Provedor de dados: 77
Autores: Olivares Paz,Alberto; Bustos-Obregón,Eduardo; Castillo Alvarez,Vivian; Zúñiga Romero,Oscar.
Octopus mimus macho madura precozmente. En general, sobre 200 g son maduros y permanecen en dicha condición hasta la muerte. En consideración a que no hay antecedentes de la fisiología testicular de los machos adultos, fueron estudiadas la función gamética mediante análisis histológico de los túbulos seminíferos y la función endocrina, cuantificando en el testículo, progesterona y testosterona, en conjunto con el crecimiento y funcionalidad de los órganos blancos del andrógeno. Se detectaron tres categorías de machos adultos: maduros jóvenes, de madurez máxima y en regresión. Los animales en regresión producen menor cantidad de ambas hormonas y muestran regresión de la función espermatogénica. La declinación de ambas funciones del testículo indica el...
Tipo: Journal article
Palavras-chave: Cefalópoda; Octopus mimus; Función testicular.
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022003000400010

Ecotoxicology and Testicular Damage (Environmental Chemical Pollution): A Review
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Hartley B,Ricardo.
This review briefly considers the testicular damage elicited by environmental chemical pollution. It includes a short comment on environmental toxicology as an introduction to environmental chemical pollution, highlighting the importance of this current field of study and its impact on male reproductive health. Furthermore an experimental animal model addressing the effect of organophosphorated agropesticides as a testicular toxicant is presented. Moreover two relevant chemical contaminants and their effect on the testis, such as the classical case of lead and the rarely reported case of Boron on spermatogenesis, are considered. Additionally, the subject of biosentinel species and their relevance for the monitoring of pollution in aquatic and/or...
Tipo: Journal article
Palavras-chave: Environmental chemical pollution-testicular damage.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022008000400009

Organophosphorous Pesticides: Their Effects on Biosentinel Species and Humans. Control and Application in Chile
Provedor de dados: 77
Autores: Espinoza-Navarro,Omar; Ponce-LaRosa,Carlos; Bustos-Obregón,Eduardo.
The environment is negatively affected by the increasing accumulation of both natural and man-made waste and by-products. Organophosphorous pesticides -malathion, diazinon and methamidophos- are used worldwide in pest control. The aim of this report is to review the effects of organophosphates on the male reproductive tract of mice, rats and earthworms, and to evaluate their projection into the human population. Assessing failures in the male reproductive system is an excellent in vivo biomarker to determine the level of toxicity of suspected pollutants. In rodents organophosphates cause decreased testicular weight and sperm density, abnormal tubular plugging and increased teratozoospermia. In earthworms they cause a significant decrease in body weight and...
Tipo: Journal article
Palavras-chave: Organophosphates; Cytotoxicity; Biomonitoring; Reproductive Health; Occupational Exposure.
Ano: 2017
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022017000300041

Octopus mimus (MOLLUSCA: CEPHALOPODA) EMBRYO MISDEVELOPMENT DUE TO CHRONIC EXPOSURE TO THE ORGANOSPHOSPHORUS PESTICICE PARATHON
Provedor de dados: 77
Autores: Gutiérrez-Pajares,Jorge L.; Olivares,Alberto; Bustos-Obregón,Eduardo.
Pesticides are of ample worldwide use. At present there is a growing concern about seawater contamination by these chemicals. Developing aquatic organisms are particularly at risk. For this reason, early development of Octopus mimus embryos under exposure to commercial Parathion was examined. Concentrations over 0.4 mM of the pesticide altered formation of the embryonic disc at the blastula stage, resulting in abnormal gastrulation and arrest of further development. This toxic effect may be due to the blockade of DNA synthesis elicited by organophosphoric pesticides causing diminished number of blastodermic cells at the time of epiboly, thus hindering the start of invagination. Seawater contamination seems, therefore, of relevance for survival of exposed...
Tipo: Journal article
Palavras-chave: Octopus mimus; Parathion; Early embryo development.
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022003000300011

SUBLETHAL DOSES OF MALATHION ALTER MALE REPRODUCTIVE PARAMETERS OF Eisenia foetida
Provedor de dados: 77
Autores: Espinoza-Navarro,Omar; Bustos-Obregón,Eduardo.
Malathion is an organophosphorate insecticide whose main acute poisonous effect is the inhibition of the enzyme acetylcholinesterase. This pesticide is widely used and has been reported to damage mice spermatogenesis. The objective of this work was to evaluate the toxic risk of malathion, earthworm Eisenia foetida (Annelida, Oligochaeta) like biological model was used and testicles and spermatozoa of animal controls and treaties were analyzed. Earthworms with developed clitellum were used and they were dewed with sublethal single doses of 0, 80, 150, 300 and 600mg of malathion for kilogram of soil (LD50 = 880mg/kg dry soil). Control groups were added only distilled water. Each group was analyzed 1, 5, 15 and 30 days post treatment. The results observed in...
Tipo: Journal article
Palavras-chave: Eisenia foetida; Malathion; Cytotoxicity; Spermatozoa; Reproductive organs.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022004000400010

Efecto de la Maca Peruana (Lepidium meyenii) y de la Melatonina Sobre el Desarrollo Testicular del Ratón Expuesto a Hipoxia Hipobárica Continua
Provedor de dados: 77
Autores: Valenzuela-Estrada,Mario; Parra,Roberto; Velasco-Martín,Juan P; Núñez,Hipólito; Regadera,Javier; Bustos-Obregón,Eduardo.
El estudio de la hipoxia hipobárica (HH) determina un problema de salud pública y laboral en poblaciones que habitan en zonas de altura. La disminución del oxígeno afecta a diferentes órganos, incluyendo el testículo. El organismo responde frente a la hipoxia estimulando la angiogénesis, el flujo sanguíneo testicular e incrementa la temperatura intraescrotal, lo cual produce un daño de la espermatogénesis. Nuestro estudio valoró el efecto que produce la HH sobre el testículo del ratón. Se utilizó una cámara hipobárica regulada a 4.200 metros sobre el nivel del mar (msnm), en periodos de hipoxia durante 8,3; 16,6 y 24,9 días, en comparación a un grupo control en normoxia (500 msnm). En estos tres grupos, a unos ratones se administró melatonina, a otros maca...
Tipo: Journal article
Palavras-chave: Hipoxia; Testículo; Maca; Melatonina; Poblaciones de Altura.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022014000100012

Effects of hypoxia on epididymal sperm parameters and protective role of ibuprofen and melatonin
Provedor de dados: 48
Autores: Vargas,Álvaro; Bustos-Obregón,Eduardo; Hartley,Ricardo.
Hypobaric hypoxia is of interest due to an increase of human populations working at high altitude. Testicular damage is related to the physiological response (neoangiogenesis) to increased intrascrotal blood flow as temperature rises. Hypoxia is a stress factor with overproduction of reactive oxygen species (ROS). The effect of hypoxia in mice reproductive parameters is analyzed. Animals were exposed to simulated hypoxia of 4,200 meters above sea level (m.a.s.l.) in a chamber for 33.2 days, both to continuous (HH) or intermittent hypoxia (HI) with an intermittency period of 4 days hypoxia /4 days normoxia (500 m.a.s.l.). The anti-inflammatory drug Ibuprofen was administered to a group of mice to control vasodilation and increased blood flow. Melatonin was...
Tipo: Journal article
Palavras-chave: Epididymal sperm; Mouse; Ibuprofen; Melatonin.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000200008