Browsing by Subject "AgNOR"

Now showing 1 - 4 of 4
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    Argyrophilic nucleolar organizer region (AgNOR) counting in astrocytic gliomas: prognostic value
    (Murcia : F. Hernández, 1996) Cardesa, Antonio; Ferreres, Joan-Carles; Figols, J.; Val-Bernal, José Fernando; Cruz Sánchez, F.F.
    In 87 astrocytic gliomas the number of AgNORs/nucleus was retrospectively studied and data correlated with the histological type of the tumors and survival. Al1 patients were treated by the same surgical team and with uniform criteria. Statistically significant differences (p<0.01) were found in relation with the AgNOR averages among the histological types of tumors. A statistically significant linear correlation (p<0.05) between the AgNOR values and survival of the patients was also found. Patients with mean AgNOR values higher than 2.23 and lower than 2.9 survived an average of 11.5I9.1 months vs. a sumival in average of 24.4I34.1 months with mean AgNOR values under 2.23 (p<0.05). Patients with AgNOR values higher than 2.9 survived, on average, 7.7I3.9 months. AgNOR counting in astrocytic gliomas is a reproducible, easy, quick method with prognostic value. AgNORs may be successfully applied in routine material to assess the growth potential of astrocytic gliomas.
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    Cellular proliferation andlor differentiation can condition modifications in the expression of AgNORs in rat anterior pituitary cells during growth
    (Murcia : F. Hernández, 1993) Carbajo, S.; Carvajal, J.C.; Rodríguez, J.; Carbajo-Pérez, E.
    The expression of argyrophilic nucleolar organizer regions (AgNORs) was studied in the anterior lobe of the hypophysis of 1-, 7-, 14-, 28- and 80-day-old rats. Mean area and numbers of AgNORs per nucleus decreased during this period with a simultaneous increase of both nuclear area and mean AgNOR-particle area. Comparison of our data on AgNOR expression with previously reported data on the proliferative activity and cell maturation and differentiation of anterior pituitary cells during a similar period led us to conclude that, at least in our experimental model, variations in the expression of AgNORs are more related to phenomena of cellular maturation than to proliferative activity.
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    Expression of argyrophilic nucleolar organizer regions (AgNORs) in the Harderian gland of male and female hamsters during postnatal development
    (Murcia : F. Hernández, 1997) Fernández-Suárez, A.; Carbajo, S.; López, J.M.; Carbajo-Pérez, E.
    The expression of argyrophilic nucleolar organizer regions (AgNORs) was studied in the different secretory cell types of the Harderian gland of male and female Syrian hamsters during postnatal development. Mean AgNOR area was calculated for each cell type in paraffin sections from 7-, 14-, 21-, a-4,5- and 90-dayold animals. AgNOR content was similar in male type Icells and in female cells, decreasing in both cell types from the 7th to the 14th day, increasing afterwards at the 21st day, and remaining at relatively stable levels from that point to the end of the study. AgNOR content of male type 11-cells was greater than in any other cell type studied, and was greater in 45- and 90-day-old animals than in 28-day-olds. Changes of AgNOR content in type 1-cells of male and female hamsters during the first two weeks seem to be related to changes in proliferative activity while metabolic activity might be responsible for changes taking place later on. Our results also support that male type 1- and type 11-cells have a different biological behaviour and that type 11-cells are far from being degenerating cells.
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    Multiparameter analysis of AgNOR in thyroid lesions: comparison with PCNA expression
    (Murcia : F. Hernández, 2004) Slowinska-Klencka, D.; Klencki, M.; Popowicz, B.; Sporny, S.; Lewinski, A.
    The aim of the study was to examine numerous features of argyrophilic proteins related to nucleolar organizer regions (AgNORs) in thyroid tumors, relate them to PCNA expression and evaluate which of these features might be useful in the diagnosis of thyroid lesions. Paraffin sections of 100 thyroid tumors were silver-stained and divided into 9 groups: nodular goiter (NG), simple adenoma (SA), microfollicular adenoma (MFA), follicular carcinoma (FC), follicular variant of papillary carcinoma (PC-F), classical variant of papillary carcinoma (PC-C), Hürthle cell adenoma (HA), Hürthle cell carcinoma (HC), and anaplastic carcinoma (AC). The slides were analyzed with the computerized system for image analysis. A weak correlation was found between PCNA expression and AgNOR size. AC differed significantly from all other examined groups in many features of AgNOR dots. Hürthle cell neoplasms were characterized by the presence of a usually single and relatively large dot. With respect to diagnosing follicular lesions, we found that the evaluation of the total area of dots in the nucleus seemed to be the most useful for discrimination: the assumption of 4.9 µm2, as a cut-off value, allowed a correct classification of 77% of FC cases. Computeraided morphometric analysis of AgNORs may be useful in the diagnostics of thyroid lesions.