Search

BACKGROUND: Investigate if the tyrosinase mRNA expression may be predictive of the outcome on ultra-thin, thin, and thick melanoma patients. AIM: In our study, we sought to correlate tyrosinase mRNA expression to the outcome in a group of 71 patients with thick, thin and ultra-thin melanomas. MATERIALS AND METHODS: 71 patients with melanomas underwent a SLNB (sentinel lymph node biopsy) at the "Sapienza" University of Rome. Among these, 38 patients had thin melanomas, while the other 33 patients had thick melanomas. In every patient's sample histology, immunohistochemistry and reverse transcriptase- polymerase chain reaction (RT-PCR) was completed. We then correlated tyrosinase mRNA expression to the statistical analysis of the outcome of patients. RESULTS: Positivity of histology was found in one patient (1.4%), immunohistochemistry in five patients (7%), and tyrosinase in 52/71 (73.2%). Thickness and tyrosinase positivity were predictive for disease progression (p < 0.05). The median follow-up was 58.24 months. There were recurrences and/or deaths in both groups of patients. CONCLUSIONS: Nodal metastasis in melanoma is uncommon, especially in patients with thin melanomas. In this study, histology and immunohistochemistry were found to be non predictive for the risk of nodal metastases, while instead, tyrosinase m-RNA expression appeared to play a role in highlighting those patients with a risk of disease progression. Moreover, no differences among the thin melanoma groups of patients (0.30-0.75 mm and 0.76-1.00 mm) were observed. [ABSTRACT FROM AUTHOR]

The morphological changes of murine hematopoietic 32D Cl3-A cell line, in which apoptosis was induced by deprivation of interleukin-3 (IL-3) from the culture medium, were studied through air operating atomic force microscopy. The subtraction of IL-3 determines the appearing of blebs on plasma membrane and cell fragmentation in several residual bodies. Areas of strong contrast in the friction images, which are nearly absent in control and necrotic cells, were detected with percentage that peaks at 6 h of IL-3 deprivation. These are the results revealing that transient modification of the plasma membrane accompanies the first steps of apoptosis pathway. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Apoptotic cell death represents an important mechanism for the precise regulation of cell numbers, and a defence mechanism against tumoral cell. bcl-2 and bax genes are known to be involved in the control of apoptotic pathways; in particular, the ratio between bcl-2 and bax represents a cell rheostat that is able to predict a cell's response toward life or death to an apoptotic stimulus. In the present study we investigated the role of bcl-2 and bax gene expression in a panel of 37 low-grade tumours of the urinary bladder, and correlated the expression of these genes to the prognosis of patients in a follow-up of more than one year. We found that levels of bax expression higher than bcl-2 in bladder tumours well correlates to a better outcome for patients. Early relapses are much more frequently observed in those patients whose tumours express more bcl-2 than bax mRNA. We conclude that the bcl-2/bax expression ratio may be considered as a marker for disease progression in low grade bladder tumours, independently of clinical staging and histological grading.

The antigenic cross-reactivity between intestinal treponemes of human and swine origin (T. hyodysenteriae and T. innocens) was studied by sodium-dodecylsulfate-polyacrylamide gel electrophoresis and western blotting techniques. Several distinct peptides, ranging in molecular weight from 14,400 to about 150,000 daltons, were recognized by SDS-PAGE analysis of twelve human and two swine hemolytic intestinal treponemes. Thirty antigenic bands were develope by homologous antiserum against treponeme D87, one of 12 human intestinal hemolytic treponemes isolated in our laboratory. An identical number of cross-reacting antigens was found when Western blots of human treponemes D87 were tested with antisera against ten other human treponemes or with antisera against swine treponemes (T. hyodysenteriae, T. innocens). Similar results were obtained when Western blots of swine T. hyodysenteriae were tested for cross-reactivity with antisera against all human intestinal treponemes.

Serum and cerebrospinal fluid of patients with multiple sclerosis, subacute sclerosing panencephalitis and other neurological disease have been tested by the indirect fluorescent antibody method for immunoglobulin M specific for measles. Only sera of three patients were positive. This feature is of little statistical importance. Nevertheless the authors emphasize the role of a possible viral infection in the pathogenesis of multiple sclerosis.