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N A Azambuja

Publications and source records attributed to N A Azambuja.

7 recordsLinked to original sources

[Pituitary adenomas: immunohistochemical study of 167 cases].

One hundred and sixty seven cases of pituitary adenoma were analysed using the immunocytochemical method of the Avidin-Biotin Complex (ABC), described by Hsu et al. (1981). Six pituitary anti-hormones were utilized: anti-prolactin (aPRL) at a 1:1,500 dilution; anti-growth hormone (aHGH) at a 1:4,000 dilution: anti-adrenocorticotrophic hormone (aACTH) at a 1:3,000 dilution; anti-thyrothrophic hormone (aTSH) at a 1:3,000 dilution; anti-luteinizing hormone (aLH) at a 1:1,000 dilution; and a anti-follicle-stimulating hormone (aFSH) at a 1:300 dilution. Incubation period was 14 to 16 hours at 4 degrees C. The survey of clinical, laboratory and radiological data of cases of pituitary adenomas was performed after reading the stained slides using the immunocytochemical method. Of the 167 cases of pituitary adenomas, 136 (81.4%) disclosed a positive immunoreaction to one or more anti-hormones, and the positivity index of neoplastic cells varied from 1 to 90%. The immunoreaction was positive exclusively to one anti-hormone in 80 cases (58.8%) and to two or more anti-hormones in 56 cases, and the association most frequently found was between both aPRL and aHGH. The positivity to the immunoreaction was distributed as follows: -100 cases were positive for aPRL, exclusively in 4 cases; -65 cases were positive for aHGH, exclusively in 22 cases; -31 cases were positive for aACTH, exclusively in 8 cases; -5 cases were positive for aTSH, exclusively in one case; -one patient presented an adenoma positive to aLH and another patient to aFSH.

Adenoma↗

A technique for collecting cerebrospinal fluid using an intraventricular cannula in rats.

The difficulty in obtaining cerebrospinal fluid (CFS) in an efficient and simple manner in rats prompts us to introduce a new technique that makes use of a cannula placed in the lateral ventricle. The cannula is implanted with a stereotaxic apparatus and the CSF is collected with a glass capillary tube. The technique has proved to work well for experiments in which the CSF must be free of blood. It also permits the collection of volumes of CSF sufficient for radioimmunoassays, and may be used in chronic experiments.

Animals↗

Acetylcholinesterase activity in the human subfornical organ.

The acetylcholinesterase activity (AChE) in the human subfornical organ (SFO) was detected by the method of Koelle and Friedenwald in 16 human brains collected between 6 and 12 hrs postmortem. The only AchE-positive structures found were neuronal cell bodies and processes, morphologically classified as stellate and fusiform neurons of large, medium and small size. Large ones prevailed in the dorsal zone. The neurons were homogeneously distributed in the rostral area of the SFO. The penetration and ramification of large blood vessels produced a decreasing neuronal density in the medium-caudal area. The architecture of the SFO in sagittal sections comprised a central zone with neurons juxtaposed to the walls of the vascular plexus, whose dendritic and axonal processes showed an intricate pattern without a special arrangement. This neuronal zone of the SFO was surrounded by a peripheral layer of neurons with axonal projections to the rostral area. This layer was thicker in the dorsal zone of the SFO, where axonal fibers "climbing-up" from the central perivascular neurons could be demonstrated. In coronal sections some neurons with prolongations of arcuate distribution connected the dorsal and ventral zones.

Acetylcholinesterase↗