Biomedical subjects
Publications and source records attributed to G Nicoletti.
The seminal and plasmatic concentrations have been examined of testosterone, 5 alpha-dihydrotestosterone, and delta 4-androstenedione in normospermic and dysspermic subjects. The results obtained did not provide evidence of significant differences of androgen levels in fertile, hypofertile and sterile men.
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Explore the source record for details and available documents.
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The expression of steroid receptors and the in vitro responsiveness to steroids were used to investigate the cell heterogeneity of a BALB/c mammary carcinoma cell line (TS/A) by means of its high- and low-metastatic clones previously selected in vitro. All the clones studied contained appreciable levels of receptors for oestrogens and for glucocorticoids. The in vitro responses of clones to 17 beta-oestradiol were very poor and comparable; conversely, a heterogeneous pattern of responsiveness to glucocorticoids was observed. In the presence of dexamethasone, the in vitro growth of high-metastatic clones was either unaffected or stimulated and dome formation was significantly increased. Dexamethasone treatment of low-metastatic clones caused inhibition of in vitro proliferation and a morphological shift from a fibroblast-like growth pattern towards the epithelial phenotype. One out of the three low-metastatic clones tested acquired the ability to form domes in the presence of dexamethasone, albeit sporadically. The in vitro treatment with dexamethasone significantly increased the lung colonization ability of the two low-metastatic clones studied, whereas no significant effect was observed with high-metastatic clones. Data presented here suggest that TS/A cell line consists of heterogeneous populations with peculiar proliferative and differentiative responses to glucocorticoids.
The effects of recombinant tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) on B16 mouse melanoma experimental metastatic ability and major histocompatibility complex (H-2b) antigens expression were studied. B16 cells exposed in vitro to TNF-alpha had an increased H-2 expression and were more metastatic than untreated cells. The simultaneous treatment with TNF-alpha and IFN-gamma amplified the enhancement of experimental metastasis and all other effects obtained with TNF-alpha alone. The B16 clone B78H1, selectively resistant to H-2 induction and to enhancement of metastatic ability by IFN-gamma, was not affected by treatment with TNF-alpha and with TNF-alpha + IFN-gamma. These findings contribute to a better understanding of the pleiotropic effects of TNF, some of which can have opposing actions in the complex tumor-host relationships.
The relationship between major histocompatibility complex (MHC) antigens and metastasis was investigated on B16 melanoma variants. B16 cell lines express low amounts of murine MHC (H-2) antigens. A high expression can be induced in line B16-A by in vitro treatment with immune interferon (IFN-gamma) or by in vivo transplant in allogeneic mice. The increase of H-2 antigens correlated with an enhancement of lung colonization in young syngeneic mice. The higher metastatic capacity of B16-A cells with induced high levels of H-2 antigens was observed also in adult mice and in young mice pretreated with cyclophosphamide. These results were confirmed investigating the behaviour of a mutant B16 clone (B78H1) which was selectively resistant to the H-2-inducing action of IFN-gamma: lung colonization ability was not increased by IFN pretreatment. The study of variants derived from individual B16-A lung colonies revealed a wide range of H-2 levels. Variants with a low expression had a low colonization ability; one out of two variants with a high H-2 expression also was poorly colonizing. IFN-gamma-mediated H-2 expression appeared to act as an enhancer, rather than a determinant of B16 metastatic capacity.
A metastasizing mouse cell line (TS/A), originated from a mammary adenocarcinoma which arose spontaneously in a BALB/c female retired breeder, has been established in vitro. It displayed a remarkable morphologic heterogeneity, which is evident in plastic adherent cultures (cell types ranging from epithelial-like to fibroblast-like) as well as in semi-solid agar cultures. The TS/A line exhibited the presence of specific cytoplasmic estradiol receptor, with a binding activity of 16 fmoles/mg cytosol protein. The in vivo growth pattern was as follows: a s.c. inoculum of 105 cells caused a 100 per cent tumor take and kill in syngeneic animals; mean survival time was 54 +/- 1 days; it did not show significant transplant immunogenicity in syngeneic animals; it was able to give rise to both spontaneous lung metastases and artificial lung colonies; it had a high capacity to grow in H-2 matched, minor histocompatibility antigen incompatible hosts (10(6) cells killed 100 per cent DBA/2 mice in 58 +/- 2 days). This line of spontaneous mammary tumor cells is proposed as a useful model for studies on the heterogeneity of the neoplastic population in relation to metastatic spread, on tumor immunogenicity, and on therapy of mammary neoplasia.
The metastatic TS/A line has been recently derived from a spontaneous BALB/c mammary tumor. When TS/A cells were cultured in 0.33 per cent agar, two morphologically distinct types of colonies were observed from which two sets of clones were obtained. E clones were derived from small, transparent colonies, whereas F clones were from large, thick, actively growing colonies. All the clones were tumorigenic in syngeneic BALB/c females. However, E clones showed higher ability than F clones to metastasize spontaneously to the lung. Comparison between E and F clones shows that the high level of spontaneous metastasization to the lung is associated with epithelial-like in vitro growth pattern, spontaneous dome formation and growth pattern in 0.33 per cent agar cultures. The ability to give rise to lung colonies following intravenous inoculation is not a predictive parameter for the spontaneous metastatic potential.
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Three different methods of sedation or sedoanalgesia using remifentanil, Propofol, or midazolam to increase intra- and postoperative comfort and to reduce neuroendocrine stress in patients who had undergone typical ambulatory cosmetic surgery under local anesthesia were studied. A sample of 90 patients who underwent upper and lower eyelid blepharoplasty to correct baggy eyelids or otoplasty to correct protruding ears was selected according to standard criteria for the study. Remifentanil provided the best tolerability profile and the most effective perioperative pain control among the substances studied, demonstrating it to be a valid drug for modern sedoanalgesia aimed at increasing the well-being of patients undergoing ambulatory cosmetic surgery.
A randomized study was conducted to compare the effectiveness of aztreonam plus clindamycin with that of gentamicin plus clindamycin for prophylaxis of infection following colorectal surgery. A total of 138 patients undergoing elective colorectal surgery were randomized to treatment with clindamycin (600 mg) plus either aztreonam (1 g) or gentamicin (80 mg) 30 minutes before and 8 and 16 hours after surgery. The study included 122 patients (88.4%) with colorectal carcinoma. Samples from the abdominal cavity and from the subcutaneous tissues were taken for bacteriologic study. All samples from the abdominal cavity yielded microorganisms; both aerobic and anaerobic bacteria were isolated. Wound infections occurred in eight patients (12.1%) in the aztreonam group and in 12 patients (16.7%) in the gentamicin group. Escherichia coli, Bacteroides species, enterococci, and staphylococci were isolated most frequently from wounds and were often isolated from bacteriologic samples from the abdominal cavity of the same patients. The incidence of septic complications reflected the extent of nutritional and immunologic impairment. No significant differences were found between groups in the rate of urinary tract or lower respiratory tract infections. Aztreonam/clindamycin appears to be a valid alternative to gentamicin/clindamycin for the prophylaxis of infections following colorectal surgery.