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M Codina

Publications and source records attributed to M Codina.

26 records · Page 2Linked to original sources
PubMedDate not supplied

Ultrastructural study of cholinergic neurons in the medial septal nucleus and vertical limb of the diagonal band of broca in the basal forebrain of the rat.

The morphology, ultrastructure and synaptic relationships of the cholinergic and non-cholinergic neurons in the medial septal nucleus (MS) and vertical limb of the diagonal band of Broca (VDB) in the basal forebrain of the rat were studied at the light and electron microscopic levels. The cholinergic neurons were localized immunocytochemically using a monoclonal antibody against choline acetyltransferase (ChAT). Morphometric and statistical analyses showed that ChAT-labelled cells presented a predominantly oval morphology in both nuclei. The sizes of the neurons were significantly larger in the VDB nucleus. Within the two nuclei, two populations of cholinergic neurons were differentiated. One of the large immunolabelled neurons presented deep indentations and prominent nucleoli in their non-immunoreactive nuclei. Their cytoplasm contained a well-organized endomembrane system composed of short cisternae of rough endoplasmic reticulum (RER). One or two lamellar bodies with a peculiar ultrastructure were frequently found intercalated in this system. The Golgi areas presented numerous coated vesicles, sequestration and multivesicular bodies, which was indicative of an intense metabolic activity in these cells. The second population of small immunolabelled neurons exhibited reduced cytoplasm with a poorly developed endomembrane system and apparent absence of lamellar bodies. The neighbouring non-immunolabelled neurons presented a different type of organization of the endomembrane system which was composed of scattered and loosely arranged elongated cisternae of RER and infrequent lamellar bodies, with a structure different from that seen in the large cholinergic neurons. We propose that the structural differences in composition of the endomembrane system and lamellar bodies observed in the three types of neurons in this study indicate different metabolic activities. Symmetrical and asymmetrical synaptic contacts were observed on somata and dendrites of labelled neurons, the latter being more frequent. ChAT-labelled axon boutons were never seen. The absence of immunolabelled axon terminals and the presence of immunolabelled myelinated axons leads us to suggest that the majority of neurons in these areas are of the long projecting type.

Animals↗
PubMedDate not supplied

Plasma immunoreactive somatostatin is elevated in diabetic ketoacidosis and correlates with plasma non-esterified fatty acid concentration.

In experimental diabetes and after the administration of beta-hydroxybutyrate and non-esterified fatty acids (NEFA), an increase in circulating immunoreactive somatostatin (IRS) has been described. Both ketones and NEFA are raised in diabetic ketoacidosis. Therefore, we decided to investigate 10 patients in diabetic ketoacidosis by measuring, on admission and throughout the initial 24 hours of therapy, circulating levels of IRS, beta-hydroxybutyrate, acetoacetate, triglycerides, blood glucose, pH and NEFA. Fluids and insulin were administered IV following a previously established protocol. Nine patients showed abnormally high levels of circulating IRS. When compared with a group of controlled insulin-dependent diabetic patients, basal IRS was high (111 +/- 15 vs 28 +/- 3 pmol/l), and remained elevated for at least 24 h despite clear improvement of metabolic status. On admission we also found elevated levels of NEFA (1.04 +/- 0.2 mmol/l), triglycerides (4.7 +/- 1.1 mmol/l), beta-hydroxybutyrate (22.1 +/- 4mmol/l), and acetoacetate (4.8 +/- 1.1 mmol/l). A significant correlation was found initially between IRS and NEFA (p less than 0.01). We conclude that circulating IRS is high in most cases of diabetic ketoacidosis. The mechanism behind this hypersomatostatinaemia could be related to the abnormalities of lipid metabolism which occur in diabetic ketoacidosis.

3-Hydroxybutyric Acid↗
PubMedDate not supplied

[Idiopathic generalised epilepsy. The value of semiology and EEG scanning in its classification].

INTRODUCTION: The different syndromes included in the idiopathic generalized epilepsies present an important overlapping of their electroclinical characteristics. AIM: To compare the two actual classifications (International classification of epileptic syndromes: ILAE of 1989 and of 2001) in a sample of patients with idiopathic generalised epilepsy (IGE) and to evaluate which electro-clinical factors were more useful in order to classify a patient into a syndrome. PATIENTS AND METHODS: 70 patients (44 women/26 men). Neurological examination and neuro-radiological examination were normal in all cases. The EEG (standard or sleep deprived) showed generalised epileptiform discharges in all patients. Clinical findings included a median age of onset 12.3 years. Most frequent first type of seizure was tonic-clonic (71%). Seizures during awakening were the most frequent (37%) and lack of sleep was the most important precipitating factor (44.7%). Generalized epileptiform discharges were present in 62.9% of the basal sleep deprived EEG, on the other hand, only 22.3% of the basal standard EEG showed epileptiform discharges, p = 0.048. 28% of patients were unclassifiable according to the 1989 ILAE classification, 7% were unclassifiable according to the 2001 ILAE classification. EEG during intermittent photic stimulation (p = 0.007), at awakening (p = 0.015) and the timetable of the seizures (seizures generalised at awakening) (p = 0.053) differentiated between idiopathic generalised syndromes of adolescence. CONCLUSION: The 2001 ILAE classification is more useful in order to classify patients with IGE because includes patients previously considered unclassifiable in the syndrome of generalised epilepsy with different phenotypes.

Adult↗