Diketopiperazines can be generated by non-enzymatic cyclization of linear dipeptides at extreme temperature or pH, and the complex medium used to culture bacteria and fungi including phytone peptone and trypticase peptone, can also produce cyclic peptides by heat sterilization. As a result, it is not always clear if many diketopiperazines reported in the literature are artifacts formed by the different complex media used in microorganism growth. An ideal method for analysis of these compounds should identify whether they are either synthesized de novo from the products of primary metabolism and deliver true diketopiperazines. A simple defined medium (X. fastidiosa medium or XFM) containing a single carbon source and no preformed amino acids has emerged as a method with a particularly high potential for the grown of X. fastidiosa and to produce genuine natural products. In this work, we identified a range of diketopiperazines from X. fastidiosa 9a5c growth in XFM, using Ultra-Fast Liquid Chromatography coupled with mass spectrometry. Diketopiperazines are reported for the first time from X. fastidiosa, which is responsible for citrus variegated chlorosis. We also report here fatty acids from X. fastidiosa, which were not biologically active as diffusible signals, and the role of diketopiperazines in signal transduction still remains unknown. Full article

The objective of this study was to assess the association of untreated traumatic dental injuries (TDI) with individual-, sociodemographic- and school-related factors among 12-year-old schoolchildren in Midwest Brazil. This cross-sectional study was carried out in 2010 in the city of Goiania, Brazil. A random sample of 2075 schoolchildren was examined and interviewed. Untreated TDI in the permanent incisors was assessed using the methodology of the Brazilian National Oral Health Survey. Rao-Scott test and multinomial logistic regression were used to analyze the associations between independent variables and three categories of TDI, using a hierarchical method. Independent variables were children’s sex, self rated color/race and size of incisal overjet, their mother’s level of schooling, and the schools’ type and geographic location. The prevalence of trauma was 17.3% (CI 95% = 15.2–19.4); enamel fractures were the most common TDI (13.1%). In the adjusted model, a higher chance of having two or more teeth with TDI was found among boys, those whose mothers had lowest level of schooling, and those attending schools located in health districts with lower socioeconomic indicators. It was concluded that the prevalence of TDI was low and that it was associated with individual factors as well as the school environments. Full article

Cancer continues to be one of the most important health problems worldwide, and the identification of novel drugs and treatments to address this disease is urgent. During recent years, marine organisms have proven to be a promising source of new compounds with action against tumoral cell lines. Here, we describe the synthesis and anticancer activity of eight new 3-alkylpyridine alkaloid (3-APA) analogs in four steps and with good yields. The key step for the synthesis of these compounds is a Williamson etherification under phase-transfer conditions. We investigated the influence of the length of the alkyl chain attached to position 3 of the pyridine ring on the cytotoxicity of these compounds. Biological assays demonstrated that compounds with an alkyl chain of ten carbon atoms (4c and 5c) were the most active against two tumoral cell lines: RKO-AS-45-1 and HeLa. Micronucleus and TUNEL assays showed that both compounds are mutagenic and induce apoptosis. In addition, Compound 5c altered the cellular actin cytoskeleton in RKO-AS-45-1 cells. The results suggest that Compounds 4c and 5c may be novel prototype anticancer agents. Full article