192 research outputs found

    High Performance Liquid Chromatography Method for the Determination of Anethole in Rat Plasma

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    Purpose: To identify and quantify anethole in the essential oil of fruits of Illicium verum Hook (star anise) and in vivo in rat plasma using reverse-phase liquid chromatography.Methods: Anethole was identified in the essential oil of the fruits of Star anise and determined by gas chromatography-tandem mass spectrometry (GC-MS), nuclear magnetic resonance (NMR), ultraviolet visible spectrophotometry (UV-VIS). A simple, sensitive and validated high performance liguid chromatography (HPLC) technique with UV-VIS detection method was developed for the determination of the compound in rat plasma using: methanol-water (85:15, v/v) as mobile phase at a flow rate of 0.2 ml/min Hypersil ODS Thermo (150 mm x 2.1 mm x 3.0 μM) as column with wavelength detection at 259 nm.Results: GC determination showed that anethole in the essential oil of star anise exhibited a retention time of 21.02 min. The validation results for anethole in plasma were satisfactory, with coefficient of determination (R2) of 0.9945 and relative standard deviation of < 3 %. HPLC run time of 4 min with a retention time of 2.73 min was the faster method to determine anethole when compared to a previously reported method which had a run time of 15 min.Conclusion: Anethole in the essential oil of Illicium verum Hook can be identified and determined by GC-MS, NMR and UV-VIS, and a superior HPLC method has been developed for the determination of the compound in rat plasma.Keywords: Anethole, High performance liguid chromatography, Star anise, Essential oil, Rat plasma, Illicium verum Hook

    Ginger Essential Oil Ameliorates Cisplatin-Induced Nephrotoxicity in Mice

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    Purpose: To investigate the effect of ginger essential oil (GEO) in an experimental model of cisplatininduced nephrotoxicity.Methods: Male mice were divided into treatment six groups (n = 7), namely: Groups I (saline), II and III (cisplatin, 10 mg/kg, i.p.) euthanized in 3th and 6th days, respectively, and IV, V and IV (GEO, 100, 200 and 400 mg/kg/day, respectively, by gavage 3, 4, 5 and 6 days after cisplatin injection). Creatinine levels and protein/creatinine ratio were determined in plasma and urine, respectively. Bone morphogenic protein (BMP-7) and tumor necrosis factor (TNF-α) levels of kidney tissues were determined while mRNA expression levels were obtained using real-time polymerase chain reaction.Results: GEO treatment reduced significantly creatinine levels to 0.53 ± 0.02; 0.48 ± 0.008 and 0.46 ± 0.02 at 100, 200 and 400 mg/kg, respectively, compared with control (0.70 ± 0.01) [p<0.05] but increased protein : creatinine ratio to 0.21 ± 0.01, 0.22 ± 0.01, 0.24 ± 0.02 compared with control (0.06 ± 0.008) [p<0.05]. Pro-inflammatory TNF-α mRNA expression was decreased to 1.46 ± 0.21, 1.39 ± 0.19 and 1.36 ± 0.09, at GEO doses of 100, 200 and 400 mg/kg, respectively, while anti-fibrotic BMP-7 mRNA expression increased to 2.05 ± 0.26 and 2.44 ± 0.42 at doses of 200 and 400 mg/kg, respectively, compared with control (0.59 ± 0.39, p < 0.05).Conclusion: GEO treatment attenuates cisplatin-induced nephrotoxicity, in part, by modulating some inflammatory cytokines.Keywords: Zingiber officinale, Ginger, Roscoe, Essential oil, Nephrotoxicity, Cisplati

    Validation of the SCID-hu Thy/Liv mouse model with four classes of licensed antiretrovirals.

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    BackgroundThe SCID-hu Thy/Liv mouse model of HIV-1 infection is a useful platform for the preclinical evaluation of antiviral efficacy in vivo. We performed this study to validate the model with representatives of all four classes of licensed antiretrovirals.Methodology/principal findingsEndpoint analyses for quantification of Thy/Liv implant viral load included ELISA for cell-associated p24, branched DNA assay for HIV-1 RNA, and detection of infected thymocytes by intracellular staining for Gag-p24. Antiviral protection from HIV-1-mediated thymocyte depletion was assessed by multicolor flow cytometric analysis of thymocyte subpopulations based on surface expression of CD3, CD4, and CD8. These mice can be productively infected with molecular clones of HIV-1 (e.g., the X4 clone NL4-3) as well as with primary R5 and R5X4 isolates. To determine whether results in this model are concordant with those found in humans, we performed direct comparisons of two drugs in the same class, each of which has known potency and dosing levels in humans. Here we show that second-generation antiretrovirals were, as expected, more potent than their first-generation predecessors: emtricitabine was more potent than lamivudine, efavirenz was more potent than nevirapine, and atazanavir was more potent than indinavir. After interspecies pharmacodynamic scaling, the dose ranges found to inhibit viral replication in the SCID-hu Thy/Liv mouse were similar to those used in humans. Moreover, HIV-1 replication in these mice was genetically stable; treatment of the mice with lamivudine did not result in the M184V substitution in reverse transcriptase, and the multidrug-resistant NY index case HIV-1 retained its drug-resistance substitutions.ConclusionGiven the fidelity of such comparisons, we conclude that this highly reproducible mouse model is likely to predict clinical antiviral efficacy in humans

    Alcances e obstáculos do accountability midiático na América Latina após a Terceira Onda da Democratização

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    Una de las más clásicas funciones normativas de los medios de comunicación en las democracias es la de ser vigilantes del poder, tanto para servir como defensores de la ciudadanía como para que la opinión pública tome correctas decisiones. El presente trabajo discute desde una posición crítica la accountability mediática en América Latina tras la Tercera Ola de la Democracia hasta el presente, la que si bien ha tenido una importante labor denunciante e investigativa en determinados casos de corrupción política, se postula como limitada por dos razones: la primera, la alta concentración de la propiedad de los sistemas de medios regionales ha provocado un bajo pluralismo informativo que puede poner en duda los verdaderos alcances e intenciones de la vigilancia que realizan los medios al poder y su aporte a las democracias. Por otra parte, y como segunda razón, las reformas de los últimos años llevadas a cabo por algunos gobiernos de liderazgo progresista o populista no han creado un ambiente propicio para esta función, al contrario, han propiciado carencias para la libertad informativa, principio básico para la accountability mediática. A modo de conclusión, se reflexiona sobre la importancia de fomentar el pluralismo informativo y la libertad de expresión como bases para la vigilancia de los medios al poder en la región latinoamericana.One of the most classic normative functions of media in democracies is to be vigilant of power, both to serve as defenders of the citizens and for the public opinion to make correct decisions. This paper discusses from a critical perspective the accountability of the media in Latin America from the Third Wave of Democracy up to date, which has been important in denouncing and investigating certain cases of political corruption, but has been limited for two reasons: the first is the high concentration of ownership of regional media systems, have led to a very low level of informative pluralism which calls into question the true scope and intentions of the surveillance that the media can carry out of power and its contribution to democracy. On the other hand, the second reason is the reforms carried out in recent years by the leadership of some progressive or populist governments that have not created a proper environment for this function, and on the contrary, have provided shortcomings for the freedom of information, a basic principle for media accountability. As a conclusion, this paper reflects on the importance of promoting informative pluralism and freedom of expression as the basis of media surveillance of power in the Latin American region.Uma das mais clássicas funções normativas dos meios de comunicação nas democracias é a de ser vigilantes do poder, tanto para servir como defensores da cidadania quanto para que a opinião pública tome decisões corretas. Este trabalho discute, sob uma posição crítica, o accountability midiático na América Latina após a Terceira Onda da Democratização até o presente, a que, embora tenha tido um importante trabalho denunciante e investigativo em determinados casos de corrupção política, apresenta-se como limitada por duas razões: a alta concentração da propriedade dos sistemas de meios regionais que provoca um baixo pluralismo informativo que pode colocar em dúvida os verdadeiros alcances e intenções da vigilância realizados pelos meios ao poder e sua contribuição para a democracia; por outro lado, e como segunda razão, as reformas dos últimos anos realizadas por alguns governos de liderança progressista ou populista que não criaram um ambiente propício para essa função; ao contrário, promoveram carências para a liberdade informativa, princípio básico para o accountability midiático. Como conclusão, reflexiona-se sobre a importância de fomentar o pluralismo informativo e a liberdade de expressão como bases para a vigilância dos meios ao poder na região latino-americana.https://revistas.udem.edu.co/index.php/anagramas/article/view/194

    Genetic polymorphisms are associated with serum levels of sex hormone binding globulin in postmenopausal women

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    <p>Abstract</p> <p>Background</p> <p>Estrogen activity plays a critical role in bone homeostasis. The serum levels of sex hormone binding globulin (SHBG) influence free estrogen levels and activity on target tissues. The objective of this study was to analyze the influence of common polymorphisms of the <it>SHBG </it>gene on serum SHBG, bone mineral density (BMD), and osteoporotic fractures.</p> <p>Methods</p> <p>Four biallelic polymorphisms of the <it>SHBG </it>gene were studied by means of Taqman assays in 753 postmenopausal women. BMD was measured by DXA and serum SHBG was measured by ELISA.</p> <p>Results</p> <p>Age, body weight, and two polymorphisms of the <it>SHBG </it>gene (rs6257 and rs1799941 [A/G]) were significantly associated with serum SHBG in unadjusted and age- and weight-adjusted models. Alleles at the rs1799941 locus showed the strongest association with serum SHBG (p = 0.0004). The difference in SHBG levels between women with AA and GG genotypes at the rs1799941 locus was 39%. There were no significant differences in BMD across SHBG genotypes. The genotypes showed similar frequency distributions in control women and women with vertebral or hip fractures.</p> <p>Conclusion</p> <p>Some common genetic variants of the <it>SHBG </it>gene, and particularly an A/G polymorphism situated in the 5' region, influence serum SHBG levels. However, a significant association with BMD or osteoporotic fractures has not been demonstrated.</p

    Glycophenotypic Alterations Induced by Pteridium aquilinum in Mice Gastric Mucosa: Synergistic Effect with Helicobacter pylori Infection

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    The bracken fern Pteridium aquilinum is a plant known to be carcinogenic to animals. Epidemiological studies have shown an association between bracken fern exposure and gastric cancer development in humans. The biological effects of exposure to this plant within the gastric carcinogenesis process are not fully understood. In the present work, effects in the gastric mucosa of mice treated with Pteridium aquilinum were evaluated, as well as molecular mechanisms underlying the synergistic role with Helicobacter pylori infection. Our results showed that exposure to Pteridium aquilinum induces histomorphological modifications including increased expression of acidic glycoconjugates in the gastric mucosa. The transcriptome analysis of gastric mucosa showed that upon exposure to Pteridium aquilinum several glycosyltransferase genes were differently expressed, including Galntl4, C1galt1 and St3gal2, that are mainly involved in the biosynthesis of simple mucin-type carbohydrate antigens. Concomitant treatment with Pteridium aquilinum and infection with Helicobacter pylori also resulted in differently expressed glycosyltransferase genes underlying the biosynthesis of terminal sialylated Lewis antigens, including Sialyl-Lewisx. These results disclose the molecular basis for the altered pattern of glycan structures observed in the mice gastric mucosa. The gene transcription alterations and the induced glycophenotypic changes observed in the gastric mucosa contribute for the understanding of the molecular mechanisms underlying the role of Pteridium aquilinum in the gastric carcinogenesis process

    Early detection and counselling intervention of asthma symptoms in preschool children: study design of a cluster randomised controlled trial

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    Background. Prevention of childhood asthma is an important public health objective. This study evaluates the effectiveness of early detection of preschool children with asthma symptoms, followed by a counselling intervention at preventive child health centres. Early detection and counselling is expected to reduce the prevalence of asthma symptoms and improve health-related quality of life at age 6 years. Methods/design. This cluster randomised controlled trial was embedded within the Rotterdam population-based prospective cohort study Generation R in which 7893 children (born between April 2002 and January 2006) participated in the postnatal phase. Sixteen child health centres are involved, randomised into 8 intervention and 8 control centres. Since June 2005, an early detection tool has been applied at age 14, 24, 36 and 45 months at the intervention centres. Children who met the intervention criteria received counselling intervention (personal advice to parents to prevent smoke exposure of the child, and/or referral to the general practitioner or asthma nurse). The primary outcome was asthma diagnosis at age 6 years. Secondary outcomes included frequency and severity of asthma symptoms, health-related quality of life, fractional exhaled nitric oxide and airway resistance at age 6 years. Analysis was according to the intention-to-treat principle. Data collection will be completed end 2011. Discussion. This study among preschool children provides insight into the effectiveness of early detection of asthma symptoms followed by a counselling intervention at preventive child health centres. Trial registration. Current Controlled Trials ISRCTN15790308
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