Search PubMed⌕ Search

Biomedical subjects

G Salvatore

Publications and source records attributed to G Salvatore.

At least 91 records · Page 5Linked to original sources
PubMedDate not supplied

Melaleuca alternifolia essential oil possesses potent anti-staphylococcal activity extended to strains resistant to antibiotics.

Melaleuca alternifolia Cheel essential oil (TTO) and its major component terpinen-4-ol were examined against a large number of clinical isolates of Staphylococcus aureus to establish their anti-staphylococcal activities. Classic and established procedures were used to study M.I.C., time-kill curves, synergism and mutational frequency. The anti-staphylococcal activity of terpinen-4-ol and TTO were superior to those of antibiotics belonging to the major families (all the tested drugs are for topical use or included in ointments, eye drops or used during surgery); terpinen 4-ol and TTO were active against strains resistant to mupirocin, fusidic acid, vancomycin, methicillin and linezolid. TTO and terpinen-4-ol were bactericidal as revealed by time-kill curves; the frequency of mutational frequency to TTO was < 2.9 x 10 9. The study demonstrates good anti-staphylococcal activity of TTO and terpinen-4-ol against a large number of S.aureus isolates and suggests the possible application of these agents for topical treatment of staphylococcal infections. This is the first extensive study on the anti-staphylococcal activity of TTO. The results suggest that this compound may have application as a topical agent for the control of superficial staphylococcal infections, including activity against organisms resistant to antibiotics which can be used, or are specific, for topical use.

Anti-Bacterial Agents↗
PubMedDate not supplied

Interaction between bcl-2 and P53 in neoplastic progression of basal cell carcinoma of the head and neck.

BACKGROUND: Basal cell carcinoma (BCC) is the most frequent tumor of the human skin and generally shows a favourable clinical behaviour. However, a percentage of BCC grows aggressively, infiltrating contiguous structures, sometimes giving distant metastases. MATERIALS AND METHODS: Bcl-2 and p53 protein expression was studied immunohistochemically in 60 cases of BCC (30 non-aggressive, BCC1 and 30 aggressive cases, BCC2) of the head and neck region with a complete clinical follow-up. RESULTS: All the BCC1 showed distinct cytoplasmic staining for bcl-2. The intensity of staining ranged from intermediate to high, with only three cases showing low positivity. Among BCC2, none of the 30 cases showed positivity for bcl-2. Bcl-2 expression was directly correlated with the BCC1 sub-type and a favourable clinical follow-up (p<0.01). Among BCC1, 27 cases were found negative for p53 protein expression while 3 exhibited only a low immunoreactivity. Among BCC2, 11 out of 30 cases showed an intermediate immunoreactivity, and 18 out of 30 exhibited high positivity for p53 protein. The expression of p53 protein correlated inversely with cellular differentiation (p<0.01). CONCLUSION: From the analysis of these results it is reasonable to consider bcl-2 and p53 protein expression as useful discriminating prognostic factors in the evaluation of BCCs of the head and neck region. In fact, the finding of clones expressing bcl-2 in a case of BCC may be indicative of an "indolent" cellular neoplastic phenotype. In other words, bcl-2 could be used as a "clonal marker" of a still favourable clinical behaviour. Conversely, the partial or complete loss of bcl-2-bearing neoplastic clones during histological transformation, with the appearance of clones expressing p53 protein in a BCC could be considered a hallmark of transition from a low-to high-grade malignancy, characterized by the emergence of cellular clones with a more aggressive phenotype, responsible for worse clinical behaviour.

Adult↗
PubMedDate not supplied

Tumor infiltrating lymphocytes in uveal melanoma: a link with clinical behavior?

Experimental and clinical evidence indicate that immunological mechanisms might be important in the clinical course of uveal malignant melanoma (UMM). We analyzed the amount and phenotype of tumor infiltrating lymphocytes (TIL) and the expression of the apoptosis-inducing molecule Fas and its ligand, FasL, on tumor cells and TIL in a selected series of UMM with the aim to establish if a correlation between their expression and the clinical behavior of UMM exists. TIL phenotype and Fas/FasL expression were evaluated by immunohistochemistry in 61 cases of formalin-fixed, paraffin-embedded UMM. Results were compared with the follow-up data of patients. Most of the UMM showed a prevalence of CD8+ CD3+ T lymphocytes, or CD4+ and CD8+ cells in equal amounts. UMM showed a variable expression of FasL, ranging from 0 to > 40% of neoplastic cells. Fas was always expressed in TIL, although with a variable extent. A subgroup of UMM showed in TIL a strongly reduced or even absent expression of TCR zeta-chain, involved in activation of T-lymphocytes. This subgroup was characterized by a worse outcome. We hypothesized that an impaired cytotoxic immune response due to the loss of the zeta-chain expression plays a primary role in the biological course of UMM. Our results indicate that the overcoming of the impairment of TCR function may represent a prerequisite for the development of new therapeutic strategies for managing UMM, suggesting that elimination of tumor cells may be possible by activation of cytotoxic cells present within ocular melanomas.

Adult↗