Localization of transforming growth factors, TGFbeta1 and TGFbeta3, in hypothalamic magnocellular neurones and the neurohypophysis.

The distribution of transforming growth factor beta (TGFbeta) in the rat and human hypothalamus and neurohypophysis was investigated by immunocytochemical techniques using rabbit polyclonal antisera against TGFbeta(1) and TGFbeta(3). Colocalization of TGFbeta(1) or TGFbeta(3) and arginine vasopressin (AVP) in the rat hypothalamus was studied by double immunolabelling in light microscopy, while their subcellular localization in the rat neurohypophysis was investigated by immunoelectron microscopy. TGFbeta(1) and TGFbeta(3) immunoreactivity was demonstrated in the cell bodies and processes of neurones in the supraoptic nucleus (SON) and paraventricular nucleus (PVN).

Polysialylated neural cell adhesion molecules expressed in human pituitary tumors and related to extrasellar invasion.

Object: Pituitary adenomas are usually benign tumors; however, some behave aggressively and metastasize. Until now, no specific marker of aggressive behavior or malignancy has been found. The polysialylated neural cell adhesion molecule (NCAM), which is highly expressed in embryonic tissues such as the brain and pituitary, is detected in some and neuroendocrine tumors.

[Prolactinoma in man: clinical and histological characteristics].

Prolactinoma usually occurs a small intrasellar tumor in women or as a large tumor in men. To determine whether the predominance of macroprolactinomas in men is due to a delay in diagnosis as has been suggested, or whether there is a sex-related difference in growth rate we conducted a retrospective study in 45 men and 51 women with prolactinomas. Preoperative prolactin level (PRL) was 2,789 573 ng/ml and mean tumor size was 26 2 mm.

Angulate lysosomes in skin biopsies of patients with degenerative neurological disorders: high frequency in neuronal ceroid lipofuscinosis.

Angulate lysosomes with intralysosomal trilamellar structures were first described in patients with metabolic peroxisomal disorders. In this ultrastructural study of skin biopsies of 139 patients with degenerative neurological disorders and 45 patients with static encephalopathies, we observed angulate lysosomes with similar ultrastructure exclusively in degenerative neurological disorders. They were found in only a few cases (8%), but especially in patients with degenerative metabolic disorders (72%).

Mono- and plurihormonal thyrotropic pituitary adenomas: pathological, hormonal and clinical studies in 12 patients.

In a series of 12 patients (eight women and four men, aged between 20 and 62 years), operated on for a pituitary adenoma shown to be thyrotropic by immunocytochemistry, we performed a retrospective and comparative analysis of clinical and biological data, tumor studies including immunocytochemistry with double labeling, and proliferation marker (proliferative cell nuclear antigen (PCNA) and Ki-67) detection, electron microscopy and culture. Our study leads us to confirm that thyrotropic tumors are rare (12 of 1174 pituitary adenomas: 1%). The main points arising were that: (1) high or normal plasma TSH associated with an increase in plasma alpha-subunit and high thyroid hormone levels is the best criterion for diagnosis; (2) the failure of TSH to respond to TRH or Werner's test is not a reliable criterion for diagnosis; (3) thyrotropic adenomas may be 'silent', without clinical signs of hyperthyroidism and with only slight increase in TSH, tri-iodothyronine and thyroxine concentrations; (4) mitoses and nuclear atypies are frequently detected in large tumors, which are invasive in more than 50% of cases - the first analysis of two proliferation markers (PCNA and Ki-67) bears out the relative aggressiveness of thyrotropic adenomas; (5) thyrotropic adenomas are frequently plurihormonal.