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A total of 550 oral streptococci: 270 Streptococcus mitis, 110 Streptococcus sanguis, 90 Streptococcus anginosus, 50 Streptococcus mutans, 30 Streptococcus salivarius, were isolated from dental plaque and gengival crevices of patients and tested for their susceptibility to 12 β-lactam antibiotics and to 5 non-β-lactam antibiotics, using the microdiluition method. Overall, a reduced susceptibility to penicillin was recorded in 13.4% of cases. The percentage of strains resistant to penicillin appeared significantly higher in S. mitis (24%) than in S. sanguis (19%), in S. mutans (14%) and in S. salivarius (10%). No levels of penicillin resistance were shown by 90 strains of S. anginosus. In susceptibility test to antibiotics, imipenem was the most active molecule tested, confirming its general good activity against oral streptococci. Also third generation cephalosporins such as ceftriaxone and fourth generation cephalosporins such as cefepime, showed good activity. Chinolones, glycopeptides and rifampicin confirmed a good activity against oral streptococci.

The presence of a sildenafil derivative, the thiosildenafil, in an herbal product has been evidenced first by HPTLC and later determined by isolation and analysis of spectroscopic data. The analyzed product is nowadays marketed as dietary supplement containing herbal extracts and claimed for male and female sexual improvement. This report is noteworthy since it is clear that adulterated materials can cause serious health problems if they are consumed as herbal "natural" products, generally considered deprived of toxicity by the consumers. The use of a simple and reliable method, based on HPTLC, to determine synthetic adulterations is reported in this paper.

The phytochemical study of Mimulus glabratus A.Gray allowed the isolation of two cyclohexenones: the new compound 6-chlorohalleridone 1 and halleridone 2. Halleridone was also identified in Mimulus luteus L., together with dihydroalleridone 3, the naphtoquinone alpha-dunnione 4, ursolic acid and beta-sitosterol.

A phytochemical profile of a botanical product (TM) from Iris tenax has been produced focused on flavonoids and iridals, leading to a useful fingerprint of the tested extract based on HPLC and NMR data.

Chlamydia pneumoniae persistent infection has been implicated in the pathogenesis of several chronic inflammatory diseases including atherosclerosis, and we hypothesized that modulation of the apoptosis of macrophages and/or T cells by C. pneumoniae infection may contribute to the development of such diseases. We therefore evaluated apoptosis, cytokine response, and redox status in human primary T cells and macrophages infected with C. pneumoniae. In addition, co-cultures of T cells and macrophages infected with C. pneumoniae were also carried out. Apoptosis, and levels of glutathione (GSH), glutathione disulfide (GSSG), and tumour necrosis factor (TNF)-alpha were measured by flow cytometry, high performance liquid chromatography and enzyme-linked immunosorbent assay. C. pneumoniae induced apoptosis in T cells as well as in co-cultures of T cells and infected macrophages by marked decrease in GSH/GSSG ratio and increased production of TNF-alpha, respectively. The results demonstrate that interaction of C. pneumoniae with T cells and/or macrophages characterized by interference with redox status, and secretion of tumour necrosis factor-alpha culminates in the induction of T cell apoptosis and survival of infected macrophages. In conclusion, the inappropriate T cell response against C. pneumoniae and survival of infected macrophages could explain the persistence of this intracellular obligate pathogen in the host-organism; it may contribute to the development of chronic inflammatory diseases, although further studies are needed to clarify such a complex mechanism.

Bovine lactoferrin (BLf) is an iron binding protein folded in two lobes, N- and C-lobes. In this study we have reported the inhibitory activity towards herpes simplex virus type 1 (HSV-1) in vitro infection of BLf tryptic digested N- and C-lobes in comparison with the whole protein. The N-lobe and C-lobe exerted an anti-herpesvirus activity 50- and 10-fold lower than native BLf, respectively. In order to assess the phase of viral replication affected, lactoferrin-derived lobes were added to the cells at different non cytotoxic concentrations, during the whole cycle of viral infection or during viral attachment step, demonstrating that both lobes interfered with the early phases of infection. Among the BLf tryptic digested fragments, two negatively-charged small peptides deriving from N-lobe, previously shown effective towards HSV-1, have been further studied. We assessed that the net negative charge of these peptides was not responsible for the antiviral activity since their activity was not modified when the aspartic and glutamic acidic residues of these peptides were replaced with asparagine and glutamine, respectively. The experiments here reported confirm a pivotal role of N-lobe in inhibiting viral infection. However, the residual inhibiting activity of C-lobe and the similar efficacy shown by negatively or positively charged peptides strongly support the idea that the antiviral activity of bovine lactoferrin cannot be fully explained simply on the basis of competition between the protein and viral recognition sites for binding to glycosaminoglycans.