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Biomedical subjects

G Campana

Publications and source records attributed to G Campana.

9 recordsLinked to original sources

Dynorphin A-(1-17) and dynorphin B are released from in vitro superfused rat hypothalami. Effects of depolarizing agents and ovariectomy.

We measured the release of immunoreactive (ir) dynorphin (dyn) A-(1-17) and dyn B from the rat hypothalamus by an in vitro superfusion technique. The system was validated on the basis of the recovery and stability of radiolabeled peptides added to the superfused hypothalami. These were detected as authentic peptides by reverse-phase high-performance liquid chromatography (rp-HPLC) only in the presence of a cocktail of peptidase inhibitors added to the superfusion medium. We observed spontaneous release of ir-dyn B, evaluated by a validated radioimmunoassay in the superfusates, that was increased by potassium and veratridine depolarization. It was calcium-dependent and tetrodotoxin-sensitive. We could not evaluate ir-dyn A-(1-17) directly in the superfusates, because the peptidase inhibitors added to the medium significantly altered the tracer-antibody reaction. To obviate this problem, pooled superfusate samples were purified on C18 cartridges and assayed by rp-HPLC. Rp-HPLC analysis of superfusates revealed two molecular forms with the same retention time as authentic dyn A-(1-17) and dyn B which were four times higher in K(+)-stimulated fractions. We could not detect dyn A-(1-32), comprising dyn A-(1-17) and dyn B, even though this peptide is recognized by the antibodies used in this study and is detected in acetic acid extracts of the rat hypothalamus. The spontaneous and K(+)-evoked release of ir-dyn A-(1-17) and ir-dyn B were significantly higher in 2-week ovariectomized rats, in parallel with the increase of their content in the anterior hypothalamus preoptic area.

Animals

[Salivary and serum beta 2-microglobulin in the diagnosis of primary Sjögren's syndrome].

beta 2-microglobulin (beta 2m) serum and salivary levels and total protein salivary levels were determined in 15 patients with primary Sjögren's syndrome (pSS), 14 patients with sicca syndrome and 11 healthy subjects. beta 2m serum and salivary levels were higher (p < 0.005) in the patients with pSS than in the healthy subjects and in the patients with sicca syndrome. The bioptic focus scores of minor salivary glands were correlated to beta 2m salivary levels with a high significance (p < 0.001) but were not correlated to beta 2m serum levels. The assessment of beta 2m serum and salivary levels is a non-invasive clinical investigation, which may be easily repeated. It is a very sensitive and highly specific test for the diagnosis of pSS. It may be therefore a useful mean to follow the natural course of pSS and to evaluate the effects of therapy.

Diagnosis, Differential

[Serum beta 2-microglobulin and HLA alloantigens in primary Gougerot-Sjögren syndrome. A possible relation with HLA-DR3 specificity].

The relationships between some allo-antigens of the HLA system and beta 2-microglobulin (beta 2m) serum level were examined in a group of 24 subjects with primitive Sjögren's syndrome (pSS). While the beta 2m serum level of all the patients with pSS were higher at the limits of significance (p congruent to 0.05), compared to the values of the 14 control subjects, the division of the patients into two sub-groups of 14 and 10 subjects, according to the presence or absence of the haplotypes DR2 and/or DR3, pointed up a beta 2m serum level which was significantly higher in the first compared to the second (p less than 0.02) and to the group of normal subjects (p less than 0.01). Among the individual haplotypes studied, only the DR3 was observed with a significantly greater frequency (p less than 0.01) in the patients compared to the control group. The haplotype DR3 and also the B8, although at a lesser level, were found to be correlated with a high value of the serum beta 2m: p less than 0.004 and p less than 0.05 respectively. A similar association was not found for the DR2 and DRW52 specificities.

Adult

[Ultrastructural observations on choroid melanoma].

Twelve melanoblastomas of the choroid of different histological types have been studied in the semi-thin sections and at transmission electron microscope. There have been also observed at scanning electron microscope. The ultrastructural findings show some differences in the main cellular types as observed at light microscope by Callender (spindle-shaped cells A and B and epithelioid). In the epithelioid and spindle-shaped B cells a higher number of ribosomes and of mitochondria and large, polymorphous, often multiple nucleoli with reticular structure are observed. There findings may be related to a greater metabolic activity and anaplastic tendency of these cells. Moreover in spindle B - and epithelioid - cell types atypical melanogenesis and nuclear bodies are particularly evident. Scanning electron microscope show well developed cytoplasmic extensions in spindle cells.

Choroid Neoplasms

[Study of uveal malignant melanoma with the electron microscope (author's transl)].

Twelve cases of uveal malignant melanoma, including the principal histologic types of this neoplasm according to Callender, were studied with the electron microscope. Nuclear inclusions were observed in each case, more frequently in epithelioid cells: they were probably correlated with nuclear hyperactivity. Melanogenesis in neoplastic cells was sometimes abnormal because of the granular structure of the premelanosomes, of the difference in size and in shape melanosomes, of the difference in size and in shape of the pigment granules and of the different stage of evolution of the premelanosomes in the cell. The size and the degree of reticulation of nucleoli and the number of free ribosomes and mitochondria increased from spindle A, to spindle B and epithelioid cells. This behaviour probably depends on an increasing metabolic activity which is related to the increasing degree of malignancy.

Adult

[Scanning electron microscopy in malignant uveal melanomas (author's transl)].

Four malignant uveal melanomas, of which two were of fascicular (subtype B) type one of epithelioid type and one of mixed-type, were examined under a scanning electron microscope. Within the tumors, we can distinguish cells having long cytoplasmatic processes and cells without processes, which correspond to the fusiform and epithelioid cells respectively. The cells also show a more or less marked development of the microvillosities of the cell surface.

Adult