Antimicrobial synergism and cytotoxic properties of Citrus limon L., Piper nigrum L. and Melaleuca alternifolia (Maiden and Betche) Cheel essential oils.

OBJECTIVES: The chemical composition, antimicrobial and synergistic effect, and cytotoxic activity of Citrus limon (lemon), Piper nigrum (green pepper) and Melaleuca alternifoila (tea tree) essential oils (EOs) were investigated. METHODS: Chemical analyses of essential oils were tested by GC-FID and GC-MS spectroscopy. The antimicrobial activity assay was conducted using microdilution method against several oral bacteria and Candida spp. originating from the humans with oral disorders. The synergistic antimicrobial activity was evaluated using checkerboard method. The cytotoxicity evaluation of EOs was assessed using MTT test. KEY FINDINGS: Limonene (37.5%) and ß-pinene (17.9%) were the major compounds in C. limon oil, ß-pinene (34.4%), δ-3-carene (19.7%), limonene (18.7%) and α-pinene (10.4%) in P. nigrum oil and terpinen-4-ol (38.6%) and γ-terpinene (21.7%) in M. alternifolia oil. The broad-spectrum antimicrobial activity was achieved by tested three EOs, with C. limon oil being the strongest against bacteria and M. alternifolia oil strongest against fungi. The EOs demonstrated synergism; their combined application revealed an increase in antimicrobial activity. All tested essential oils showed lower cytotoxic activity in comparison with the positive control, and the obtained results confirmed a dose-dependent activity. CONCLUSIONS: The results of this study encourage use of tested EOs in development of a novel agent intended for prevention or therapy of corresponding oral disorders.

Association of TP53 codon 72 polymorphism with susceptibility to ovarian carcinomas in Serbian women.

OBJECTIVES: Finding a potential genetic factor associated with a deadly disease, such as ovarian carcinoma, is of particular importance. The aim of this study was to examine the role of the TP53 codon 72 polymorphism in ovarian carcinoma development in Serbian women. STUDY DESIGN: 47 wild-type TP53 gene ovarian carcinoma samples and 70 cervical smears from gynecologically healthy women were analyzed. DNA was extracted by a salting-out procedure. Codon 72 polymorphism was assessed by PCR-RFLP method. χ(2), Fisher exact test and odds ratio were used for statistical analysis. RESULTS: The distribution of Arg/Arg, Arg/Pro and Pro/Pro genotypes of codon 72 of the TP53 gene was: 46.8%, 46.8% and 6.4%, respectively in the ovarian carcinomas and 64.3%, 31.4% and 4.3%, respectively in the control group. We observed an increased risk for the development of ovarian carcinoma for Pro homozygotes in relation to heterozygotes plus Arg homozygotes (OR=1.52; 95% CI 0.29-7.89) and a higher one for Pro/Pro plus Arg/Pro genotype in relation to Arg homozygotes (OR=2.04; 95% CI 0.96-4.34). CONCLUSION: The results showed no association between codon 72 TP53 gene polymorphism and risk for development of ovarian carcinoma in Serbian women. However, this observation requires further analysis of a larger case-control study group.

Novel trans-dichloridoplatinum(II) complexes with 3- and 4-acetylpyridine: Synthesis, characterization, DFT calculations and cytotoxicity.

Novel complexes of platinum(II) with 3- (1) or 4-acetylpyridine (2) have been synthesized and characterized by elemental analyses, IR, (1)H and (13)C NMR spectroscopy. Single crystal X-ray diffraction revealed the trans geometry of complex 2. DFT calculations confirm formation of trans isomers for both complexes. The complexes have been tested for their cytotoxicity against HeLa (human cervical cancer), U2OS (human osteosarcoma), U2OScisR (human osteosarcoma cisplatin resistant), B16 (murine melanoma), MDA-453, MDA-361, and MCF-7 (human breast cancer), LS-174 (human colon cancer) and FemX (human melanoma) cell lines. The most promising compound trans-dichloridobis(4-acetylpyridine)platinum(II) (2) overcomes cisplatin resistance of U2OScisR cells after 48h of drug exposure.