Biomedical subjects

M J Madariaga

Publications and source records attributed to M J Madariaga.

5 recordsLinked to original sources

PubMed2001

Morphological study of 5-HT neurons and astroglial cells on brain of adult rats perinatal or chronically exposed to 2,4-dichlorophenoxyacetic acid.

2,4-D is a chlorophenoxyherbicide used worldwide. We have studied the morphological alterations of 5-HT neurons and glial cells in the mesencephalic nuclei of adult rats exposed to 2,4-D both perinatally (during pregnancy and lactation) and chronically (during pregnancy, lactation and after weaning) with quantitative methods. Pregnant rats were daily exposed to 70 mg/kg of 2,4-D from gestation day (GD) 16 to post-natal day (PND) 23 through diet. After weaning, pups were assigned to one of two sub-groups: T1 (fed with untreated diet until PND 90) and T2 (maintained with 2,4-D diet until PND 90). Brain sections were immunocytochemically stained using polyclonal anti-5-HT, anti-GFAP and anti-S-100 protein antibodies as cells markers. 2,4-D exposure during pregnancy and lactancy (T1 group) produced an increase in 5-HT neuronal area and immunoreactivity (IR) in the mesencephalic nuclei studied. However, with the chronical 2,4-D exposure (T2 group) only the 5-HT neuronal area from the dorsal raphe nucleus (DRN) was increased, suggesting an adaptable response of 5-HT neurons in median raphe nucleus (MRN). The presence of reactive astrocytes in mesencephalic nuclei and in hippocampus were also different for the two 2,4-D exposure designs, showing the existence of a correspondence between neuronal changes and astrogliosis. Results support evidences that 2,4-D alters the serotoninergic system and that 5-HT neurons of each mesencephalic nuclei show different responses to the 2,4-D exposure designs which are parallel to astrogliosis.

2,4-Dichlorophenoxyacetic Acid↗

PubMed1999

Intoxication by non-protein nitrogen compounds in rat feed.

Last year our white rats (Wistar origin) showed acute behavioral and physiological changes followed by death in 70% of the animals. We detected that the malfunctions could be attributed to the new batch of laboratory rat pellets provided two weeks before. High levels of urea (260 mg/kg) and ammonia (540 mg/kg) were found in the feed while usual values in other similar feed were 48 mg/kg and 82 mg/kg respectively. Suspecting an ammonia intoxication, concentrations of ammonia and urea were determined in blood, brain and liver. Brain neurotransmitters and blood tryptophan and serotonine (5-HT) were also determined. Blood ammonia in rats fed the contaminated feed was about 100% higher than those fed the normal feed while liver and brain ammonia were three and four fold high respectively. Liver and brain urea were four to five fold and about 100% higher in the exposed group than in the group fed the control diet respectively. Blood 5-HT increased 62.33% in females and 99% in males whereas brain 5-HT increased 83.13% in females and 70.47% in males. But, we detected a 59.8% decrease in brain dopamine levels in females and a 38.65% decrease in males. Liver histology showed small droplets of fat stores mainly in centrolobular hepatocyte. No differences in blood or liver cholesterol concentrations were observed whereas liver triacylglycerides were significantly higher in intoxicated females. This study illustrates a problem of food borne intoxication that justifies the need for exhaustive analyses of even not usual compounds in every feed batch; moreover, it is demonstrated that rat behavior appears to be the earliest biomarker of ammonia exposure.

Ammonia↗

PubMed1995

Intraoperative anaphylaxis caused by a hydatid cyst.

The incidence of the hydatid disease is still high in some regions of the Mediterranean. A serious, but rare, peroperative complication is IgE-mediated anaphylaxis, as a result of passing of the highly antigenic hydatid cyst content into the bloodstream. We present here a case of anaphylactic reaction in a patient who underwent surgical treatment of hydatid cyst.

Adult↗

PubMedDate not supplied

2,4-Dichlorophenoxyacetic acid in developing rats alters behaviour, myelination and regions brain gangliosides pattern.

Neonate rats were exposed to 100 mg/kg from the PND 7 to PND 25 or at 70 mg/kg from PND 12 to PND 25. Treated and control pups were subjected to several behavioral tests (righting reflex, negative geotaxy, forelimbs support and open field) during the period of treatment. At PND 25 the regional effects of 2,4-D on gangliosides composition and myelin deposition were determined. The results indicate that the first design of exposure to 2,4-D produces significant diminutions in body and brain weight from PND 21. Furthermore, these pups showed decrease in GM1 level, diminution in myelin deposition and alterations in all behavioral tests. On the other hand, when treatment was not too severe (minor dose and shorter period of treatment), pups showed alterations in forelimb support and in open field tests without body or brain weight modifications. They also presented diminutions in GM1, mayoritary ganglioside of myelin, and in myelin deposition. These results suggest that in this latter 2,4-D exposure design, undernutrition could not be involved.

2,4-Dichlorophenoxyacetic Acid↗

PubMedDate not supplied

[Intraoperative hydatid anaphylactic shock].

Certain parts of Spain continue to have a high incidence of hydatid disease. Anaphylaxis mediated by IgE, due to the high concentration of antigens in the blood stream, is a serious but fortunately infrequent complication of surgery. We present two cases of anaphylactoid reaction in patients undergoing surgery for excision of hydatid cysts and one case of a patient scheduled for cholecystectomy with unsuspected hydatid disease. This represents three cases presenting vascular collapse accompanied by metabolic acidosis, from among a total of 53 surgical patients handled by our department between January 1992 and May 1993. Early, essentially clinical, diagnosis and immediate start of treatment with adrenaline, suspension of inhaled anesthetics, administration of 100% oxygen, and restoration of intravascular volume with colloids or crystalloids were decisive in assuring the favorable outcome for these patients. Hydatid disease must be considered as a differential diagnosis in cases of shock during surgery in areas where it is endemic. Although infrequent, the possibility of anaphylaxis must be kept in mind whenever there is sudden hemodynamic deterioration during surgery for removal of a hydatid cyst. Early diagnosis and appropriate treatment are essential for a favorable outcome.

Adult↗