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R Nano

Publications and source records attributed to R Nano.

85 records · Page 5Linked to original sources

Immunohistochemical evaluation of minichromosome maintenance protein 7 in astrocytoma grading.

The minichromosome maintenance (MCM) proteins, which play an important role in eukaryotic DNA replication, represent a group of proteins that are currently under investigation as novel diagnostic tumor markers. Several studies have proved a greater reliability of MCM proteins to stain proliferating cells compared to Ki67 protein, a routinely used proliferation marker in histopathology. In the present study, the expressions of MCM7 and Ki67 were estimated in 66 primary human astrocytomas in relation to tumor grade (Grade I-IV, WHO). MCM7 significantly stained more nuclei compared to Ki67 in all the histopathological grades investigated. In addition, a stronger increase of the MCM7 labelling index, in relation to the tumor aggressiveness, was observed.

Astrocytoma↗

DNA-protein cell content of lymphokine activated killer (LAK) and target cells in coculture.

An extensive study of the interactions between LAK-target cells in cocultures was performed by means of cytometric (relative DNA and protein content) and morphological parameters. The aim was to obtain new information about the cell cycle stage of tumor target cells (Chang line) during the attack of LAK cells. Specimens obtained from cocultures at 0, 24, 48 hours were processed for electron microscopy, flow cytometry, immunocytochemistry (anti-BrdU reaction) and light microscopy (L.I., M.I., cell-cell interaction). The most intense activity of LAK cells against the target was found at 24 hours of coculture independently of the proliferative stage of the tumor cells. These results suggest that the high affinity between killer and target cells was not affected by the molecular changes of the Chang cell surface during the cell cycle.

Cell Communication↗

Morphofunctional characterization of lymphokine activated killer (LAK) cells in vitro.

In order to characterize the cellular subsets of peripheral blood lymphocytes cultured with interleukin-2 (IL-2), a study in vitro was developed. Both conditioned medium from PHA-stimulated lymphocytes and recombinant IL-2 (rIL-2) were employed. The following aspects were examined: the morphological pattern of IL-2 stimulated lymphocytes; the ability of these cells to recognize, bind, attack and destroy tumoral lines; their cytochemical and immunological (CD) feature. The results suggest that, in our experimental conditions, these cells showed a characteristic "hand mirror shape", cytotoxic antitumor activity, lack of hydrolytic enzymes and CD3+, CD4+ phenotype.

Cells, Cultured↗

Cell activation and death (apoptosis) induced by IL-2: ultrastructural evidence.

Peripheral blood cells of cancer patients with advanced renal carcinoma and treated with interleukin-2 by intravenous application were studied by electron microscopy at different intervals from the beginning of rIL-2 administration. Morphofunctional modifications of lymphocytes, circulating hystiocytes containing phagocitated bodies and polimorphonucleated cells undergoing phagocytosis were observed with a time dependent increase of altered cells. The analysis of blood cells cultured in the presence of recombinant IL-2 confirmed the in vivo results. Our data suggest that IL-2 induces apoptotic phenomena in the peripheral blood cells of treated patients.

Apoptosis↗

Activated lymphoid cells in human gliomas: morphofunctional and cytochemical evidence.

To study defensive infiltrating cells, smear preparation from 20 fresh gliomas and autologous normal peritumoural brain tissue, used as control, were analysed. May-Grünwald Giemsa staining and cytochemical reaction markers of cellular functions [acid phosphatase (AP), dihydrofolate reductase (DHFR), dipeptidilpeptidase (DAP IV) and serine esterase BLT-dependent (SE)], were employed to characterize the cells. The extent of the leukocytic infiltration and the percentage of activated lymphocytes ("hand mirror" shape lymphocytes: HMS; lymphocytes binding tumor: LBT) were also studied. In addition serum levels of T cell growth factor interleukin-2 (IL-2) and of the soluble IL-2 receptor (sIL-2R) were determined in the affected patients. In tumoural imprints, mostly in astrocytomas, we observed an increased percentage of DHFR and DAP IV positive lymphocytes, of HMS lymphocytes and of lymphocytes binding tumoral cells. Serum levels of IL-2 were significantly increased in all patients whilst sIL-2R levels, were high only in glioblastoma. These findings indicate that in malignant gliomas there is stimulation of the immune system as witnessed by the presence of activated cells inside tumor tissue and soluble activating factors in serum.

Acid Phosphatase↗

Cytochemical demonstration of nitric oxide synthase and 5' nucleotidase in human glioblastoma.

Both nitric oxide (NO), formed from L-arginine by the enzyme nitric oxide synthase (NOS), and adenosine, which is produced by 5' nucleotidase (5' N) acting on adenosine 5' monophosphate (5' AMP) are implicated in several neurophysiological processes. In addition, 5' N is a linker protein involved in cell motility. Alterations of both enzyme activities seem to be responsible for some pathological states of the central nervous system (CNS). In the present report, we have studied the cytochemical demonstration of NOS and 5' N activities in human glioblastoma cells. Enzyme activity of both was observed in tumor cells; moreover, the coincidence of enzyme histochemistry and immunohistochemistry for NOS was noted in most cases. The findings were interpreted on the basis of the cytotoxic effects due to NO production by tumor cells, and on the non-catalytic role of membrane 5' N which acting as an adhesive molecule can favour tumor invasiveness.

5'-Nucleotidase↗

Effects of interleukin-2 for the treatment of malignant mesothelioma.

The hematological profile, and clinical parameters in mesothelioma affected patients undergoing a clinical trial to evaluate the efficacy of IL-2 treatment were investigated. Six patients were monitored for 6 weeks following therapy. Blood cell count, morphological and immunophenotypical analysis were performed, as well as clinical evaluations of the patients before and after therapy. Activation of the immune system (increase in lymphocytes, monocytes, eosinophils and HMS lymphocytes) induced by IL-2 was observed. The treatment was well tolerated: our patients had only mild adverse reactions controlled by symptomatic therapy. Eosinophilia represented the most evident negative effect. A slight decrease in CD4-positive subset of lymphocytes was observed after rIL-2 treatment. The therapy did not induce significant changes in the progression of the disease. In one patient necrosis at the tumoral site was observed after loco-regional rIL-2 administration.

Blood Cell Count↗