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J P Diaz

Publications and source records attributed to J P Diaz.

5 recordsLinked to original sources
PubMed1998

Insulin during the early postembryonic development of the gilt-head sea bream, Sparus aurata: ultrastructural, immunohistochemical, and biochemical studies.

Insulin was sought during the early postembryonic development of gilt-head sea bream, Sparus aurata, using ultrastructural, immunohistochemical and biochemical techniques. The endocrine pancreas appeared at hatching (Day 0) as a single cluster of morphologically similar cells. Secretory granules formed from Day 1 onwards but the cells could only be identified as insulin-producing B cells at the end of the endotrophic period (Day 3-Day 4). Insulin-immunoreactive cells were detected in the pancreatic primordium from hatching onwards and their number increased after the end of the endo-exotrophic period. Early insulin production was also found using an ELISA method on homogenates of prelarvae and larvae. Insulin levels were fairly high during the endotrophic period, decreased strongly at mouth opening, and then increased at the end of the endo-exocrine period. The origin and role of the large amount of hormone detected during the strictly endotrophic phase of ontogenesis are discussed in light of data on other vertebrates.

Animals↗
PubMed1990

Maturation of the endocrine pancreas in the sea bass, Dicentrarchus labrax L. (Teleostei): an immunocytochemical and ultrastructural study. I. Glucagon-producing cells.

The structure of the endocrine pancreas in the sea bass (Dicentrarchus labrax L.) was studied with special reference to glucagon-immunoreactive cells. As described in most of the teleosts, the sea bass was found to have a diffuse pancreas. In the adult, endocrine cells were clustered in a principal islet and numerous accessory islets where the glucagon A cells were localized peripherally. Under electron microscopy, the A cells displayed a clear hyaloplasm with granules having typical spherical or polyhedral cores, as in other vertebrates. The maturation of the endocrine pancreas was monitored under rearing conditions. The endocrine pancreas appeared during the prelarval stage, 3 days after hatching, and consisted of a single cluster of morphologically similar cells, containing very small cytoplasmic granules. During the larval stage, cytodifferentiation resulted in modifications of cell shape and increased granule size. Typical granules appeared in 8-mm-long larvae. Cells immunoreactive with mammalian glucagon antibodies appeared only at the beginning of the juvenile stage (3 months/20 mm). Electron microscope observations revealed that the storage of hormone in numerous cytoplasmic granules began at this stage.

Animals↗
PubMed1980

[An integrated program for psychosis].

The reciprocal balance between the cognitive normal awareness of reality and the cognitive psychotic awareness of reality in schizophrenia, is proposed, on the basis of the structural psychopathological theory of psychoses of the author. This balance points to the dominance of the operant conditioning of psychotic reality over normal reality during the invasion period of the disease, an equilibrium of both aspects during the steady period, and a dominance of normal reality during the residual period. A comprehensive program for secondary and terciary prevention of schizophrenia is outlined, with five levels of function delegation: D1, psychiatrists and psychologists; D2, nurses and social workers; D3, auxiliary nurses; D4, family co-therapist; D5, patients and other relatives. The functions delegated to D5 include the recognition of symptoms, causes and course, and attitudes conducing to secondary handicaps in patients. To D4, are delegate the administration of psychotropic drugs at home and technique for reinforcing normal reality. To D3, are delegated notions on epidemiology, the supervision of the psychopharmacological treatment and of reinforcement programs for normal reality, attitudes and its change, and notions of urgencies in psychosis. The D2 and D1 levels indicate treatment at all levels and treat the more complicated cases in institutions. The efficacy of the program in 36 cases, after a year, indicates a reduction of acute psychotic productivity from 72 to 6% of the patients, and a rate of hospitalization of only 8%.

Adult↗