Maternal hypothyroxinemia impairs spatial learning and synaptic nature and function in the offspring.

Neurological deficits in the offspring caused by human maternal hypothyroxinemia are thought to be irreversible. To understand the mechanism responsible for these neurological alterations, we induced maternal hypothyroxinemia in pregnant rats. Behavior and synapse function were evaluated in the offspring of thyroid hormone-deficient rats. Our data indicate that, when compared with controls, hypothyroxinemic mothers bear litters that, in adulthood, show prolonged latencies during the learning process in the water maze test. Impaired learning capacity caused by hypothyroxinemia was consistent with cellular and molecular alterations, including: 1) lack of increase of phosphorylated c-fos on the second day of the water maze test; 2) impaired induction of long-term potentiation in response to theta-burst stimulation to the Schaffer collateral pathway in the area 1 of the hippocampus Ammon's horn stratum radiatum, despite normal responses for input/output experiments; 3) increase of postsynaptic density protein 95 (PSD-95), N-methyl-D-aspartic acid receptor subunit 1, and tyrosine receptor kinase B levels in brain extracts; and 4) significant increase of PSD-95 at the PSDs and failure of this molecule to colocalize with N-methyl-D-aspartic acid receptor subunit 1, as it was shown by control rats. Our findings suggest that maternal hypothyroxinemia is a harmful condition for the offspring that can affect key molecular components for synaptic function and spatial learning.

[Hyperfunctioning thyroid carcinoma. Description of a case]. / Carcinoma tiroideo iperfunzionante. Descrizione di un caso.

Differentiated thyroid cancers account for 1% of all neoplasias but only for 2.3% of thyroid nodules. A particular condition is represented by the association with hyperthyroidism, which is found in about 7% of cases. Even more rarely may be themselves cause of thyrotoxicosis. In the present paper, the case of a 66-year old male patient, bearing a recently appeared goiter, referred to us for suspicion of lung cancer and hyperthyroid symptoms, is reported. Among appropriate investigations, the finding of high titer of thyroglobulin in the aspiration needle and cytology examination suggested that thyroid lesion was primary and not metastatic, while scintiscan with J-131 isotope showed that excess of thyroid hormones was just due to it; histological diagnosis was of papillary carcinoma. As to the pathogenesis of the neoplasma during hyperthyroidism, a causal role of thyroid stimulating auto-antibodies has been suggested in the cases associated with Graves' disease, absent in our patient, which could elicitate cancer progression in the mean time. Interestingly, activating mutation of thyroid hormone receptor (TSH-r) gene has been demonstrated in a hyperfunctioning differentiated cancer. Notwithstanding the unexpected clinical behaviour may appear very rare, molecular biology studies on aspiration biopsies (FNAB) will allow, in the future, to better define the neoplastic nature of some hot nodules. In personal opinion, this particular pathology must be attently searched both for its implications in the prognosis and therapeutic strategy and because it could be less rare than generally considered up to now.

Hypopituitarism and antiphospholipid syndrome.

Vascular damage is a well known cause of hypopituitarism since Sheehan's report of postpartum pituitary necrosis; it has subsequently been reported that also sickle-cell anemia, eclampsia, pituitary apoplexy and other pathologies may induce failure of the anterior hypophysis through this mechanism. The antiphospholipid syndrome (APS) is characterized by widespread arterial and venous thrombosis with resulting different clinical features; Addison's disease due to adrenal thrombosis is the only endocrine involvement reported so far in this syndrome. We report here a case of global anterior pituitary insufficiency which developed soon after cerebral ischaemic stroke in a 62 year aged woman with Lupus aicoagulant activity (LAC) and large atrial thrombosis; underlying pathologies were excluded by appropriate investigations. Therefore in our opinion this is the first case in which anterior hypopituitarism is reported in the clinical constellation of APS and the second type of endocline involvement.