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Background Myrislignan is a natural product from Myristica sp. with diverse pharmacological activities. Recently, the anti-Toxoplasma gondii (T. gondii) activity of myrislignan has been proposed, and in vivo studies of its pharmacokinetics in BALB/c mice are necessary to further evaluate the clinical effects of myrislignan. Results In this study, a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify myrislignan levels in mouse plasma using dehydrodiisoeugenol as an internal standard (IS) in positive ion mode. Chromatographic separation of the analytes was achieved using an ACE Ultracore Super C18 analytical column (2.5 μm, 2.1 × 50 mm) at 30 °C. A gradient mobile phase consisting of water (0.1 % formic acid) and acetonitrile (0.1 % formic acid) was delivered at a flow rate of 0.4 mL/min. Myrislignan and the IS eluted at 1.42 and 1.71 min, respectively. A good excellent linear response across the concentration range of 1-1000 ng/mL was achieved (r2 = 0.9973). The lower limit of quantification (LLOQ) was 1 ng/mL, and the inter- and intra-day accuracy and precision of the method showed relative standard deviations (RSDs) less than 10 %. The method was applied to examine the pharmacokinetics of myrislignan in mouse plasma following a single oral administration of 200 mg/kg or intraperitoneal administration of 50 mg/kg myrislignan, and the bioavailability (F) of orally administered myrislignan was only 1.97 % of the bioavailability of intraperitoneally administered myrislignan. Conclusions A rapid and sensitive LC-MS/MS method has been was developed, validated and successfully used to determine myrislignan levels in mice after oral or intraperitoneal administration. This study is the first to report the pharmacokinetic parameters of myrislignan in mice and to compare its pharmacokinetics after oral and intraperitoneal administration, which will be useful for further research on the administration of myrislignan in animals and humans.

Background There is an urgent need to develop and test novel compounds against malaria infection. Carrageenans, sulphated polysaccharides derived from seaweeds, have been previously shown to inhibit Plasmodium falciparum in vitro. However, they are inflammatory and alter the permeability of the blood–brain barrier, raising concerns that their use as a treatment for malaria could lead to cerebral malaria (CM), a severe complication of the disease. In this work, the authors look into the effects of the administration of λ-carrageenan to the development and severity of CM in BALB/c mice, a relatively non-susceptible model, during infection with the ANKA strain of Plasmodium berghei. Methods Five-week-old female BALB/c mice were infected with P. berghei intraperitoneally. One group was treated with λ-carrageenan (PbCGN) following the 4-day suppressive test protocol, whereas the other group was not treated (PbN). Another group of healthy BALB/c mice was similarly given λ-carrageenan (CGN) for comparison. The following parameters were assessed: parasitaemia, clinical signs of CM, and mortality. Brain and other vital organs were collected and examined for gross and histopathological lesions. Evans blue dye assays were employed to assess blood–brain barrier integrity. Results Plasmodium berghei ANKA-infected BALB/c mice treated with λ-carrageenan died earlier than those that received no treatment. Histopathological examination revealed that intracerebral haemorrhages related to CM were present in both groups of infected BALB/c mice, but were more numerous in those treated with λ-carrageenan than in mock-treated animals. Inflammatory lesions were also observed only in the λ-carrageenan-treated mice. These observations are consistent with the clinical signs associated with CM, such as head tilt, convulsions, and coma, which were observed only in this group, and may account for the earlier death of the mice. Conclusion The results of this study indicate that the administration of λ-carrageenan exacerbates the severe brain lesions and clinical signs associated with CM in BALB/c mice infected with P. berghei ANKA.

Resumen del trabajo presentado al Food Allergy and Anaphylaxis Meeting (FAAM-2011) celebrado en Venecia.

The Simian Virus 40 (SV40) large T antigen is multifunctional protein with DNA helicase, RNA helicase and ATPse activities which contribute to multistep tumorogenesis in rodents and humans. The Immortomouse mouse strain expresses a mutated large T antigen tsA58 oncogene under the control of the interferon inducible murine H-2Kb promoter on chromosome 16. Our aim was to establish a BALB/c strain of H-2Kb-tsA58 immortomice that could be utilized to investigate specific pathological and physiological patterns associated SV-40 oncogenicity and generation of conditionally immortal cells lines.

Background In the last years, plants are being used for the production of a wide variety of biopharmaceuticals, including cytokines, and have the potential to serve as vehicles for mucosal administration of these molecules. We had previously reported the expression of a cytokine, interleukin-12 (IL-12), in transgenic tomato plants and had demonstrated that it retained its biologic activity in vitro. Findings In this work, we administered crude extracts of IL-12-containing tomato fruits to mice through the intratracheal route, measuring endogenous IL-12 and determining biologic activity by quantification of interferon-gamma (IFN-γ) in lungs and by histological analysis. IFN-γ expression in lungs, as well as histological analysis, indicate that tomato-expressed IL-12 retains its biologic activity and, most importantly, its effects are restricted to the site of administration. Conclusion Our results indicate that the functional activity of tomato-expressed IL-12 is comparable to that of commercial recombinant IL-12 when given via the mucosal route. This opens the possibility of using crude extracts prepared from tomatoes expressing IL-12 for certain immunotherapies.