Chronic stress and its effects on adrenal cortex apoptosis in pregnant rats.

The model of chronic intermittent stress by immobilization during pregnancy may produce alterations in the mechanisms that maintain adrenal gland homeostasis. In earlier investigations using this model, significant variations in plasma prolactin and corticosterone levels, and adrenal gland weights were observed. We hypothesized that chronic stress causes changes in apoptosis in the adrenal glands of pregnant rats.

Effects of differential pulse frequencies of chicken gonadotrophin-releasing hormone-I (cGnRH-I) on laying hen gonadotrope responses in vitro.

The aim of this work was to determine the effects of cGnRH I pulse frequencies on FSH and LH release and the changes in features and number of cultured laying hen FSH-cells and LH-cells in vitro. Primary adenohypophyseal cell cultures taken from laying hens were stimulated by four 5 min pulses using 1 or 10 nM cGnRH, administered with interpulses between pulses at 15, 30 or 60 min. Pulse frequencies and dose dependent effects were examined in six separate experiments including two controls.

Chronic stress effects on the apoptotic index of the adrenal cortex of pregnant rats.

Chronic stress by immobilization during gestation can alter several mechanisms that maintain homeostasis in adrenal gland. The aim of this work was to quantify the apoptotic index of adrenal cortex during mid-pregnancy and to prove cytological characteristics by electron microscopy. The apoptotic index did not present significant differences between the adrenal cortex areas of control and experimental rats in any of the three ages studied.

15-Deoxy-Delta12,14-prostaglandin J2 and peroxisome proliferator-activated receptor gamma (PPARgamma) levels in term placental tissues from control and diabetic rats: modulatory effects of a PPARgamma agonist on nitridergic and lipid placental metabolism.

15-Deoxy-Delta(12,14)-prostaglandin J2 (15dPGJ2) is a peroxisome proliferator-activated receptor (3) (PPAR(3)) ligand that regulates lipid homeostasis and has anti-inflammatory properties in many cell types. We postulated that 15dPGJ2 may regulate lipid homeostasis and nitric oxide (NO) levels in term placental tissues and that alterations in these pathways may be involved in diabetes-induced placental derangements. In the present study, we observed that, in term placental tissues from streptozotocin-induced diabetic rats, 15dPGJ2 concentrations were decreased (83%) and immunostaining for nitrotyrosine, indicating peroxynitrite-induced damage, was increased.

Modulatory effect of leptin on nitric oxide production and lipid metabolism in term placental tissues from control and streptozotocin-induced diabetic rats.

Leptin production by placental tissues contributes to its circulating levels and functions. The diabetic pathology induces alterations in leptin levels. In the present study, leptin levels were evaluated in placental tissue from control and neonatal streptozotocin-induced (n-STZ) diabetic rats during late gestation.

[Acute infectious gastroenteritis in Rio Cuarto: clinic, diagnosis and epidemiology with special reference to viral infections].

The objectives of the present study are to describe the clinics view of acute infectious gastroenteritis (GE) at the community, in primary and secondary attention health centers, with special references to viral aetiology (VIGE); to correlate with drinkable water and excrete treatment; to develop for the first time a fast diagnostic using electron microscopy in Río Cuarto, Córdoba, Argentina, considering the university and community collaboration in the viral diagnostic. It has been during one year, 122 cases of acute GE, over its clinics epidemiology and diagnostic aspects (1999-2000). With conventional laboratory methods, it has been determined the bacteria and micotic aetiology (NOVIGE); the virology diagnostic with electron microscopy; and the use of the statistics for the data analysis.

Characterisation of glycoconjugate sugar residues in the vomeronasal organ of the armadillo Chaetophractus villosus (Mammalia, Xenarthra).

Conventional carbohydrate histochemistry and the binding patterns of 21 lectins were analysed to characterise the glycoconjugate content in the components of the vomeronasal organ of the armadillo Chaetophractus villosus. The mucomicrovillous complex of the sensory epithelium bound most of the lectins studied. No reaction was observed with Con A, PSA, S-Con A and SBA, and the sustentacular cells were-stained with UEA-I, DSL, LEL, STL and Con A.

[Effects of parathion on acetylcholinesterase activity in rat kidney].

In this work the effects of parathion (a competitive acetylcholinesterase inhibitory agent) on the enzyme activity was studied by cytochemical methods in the kidney of rats; being the doses used not inhibitory of red blood cells acetylcholinesterase (subtoxic dose). Two groups of rats were used: control (CR) and parathion-treated (TR) groups, both submitted to a water deprivation period of 24 h. for induction of primary thirst.