Natación artística en niñas: antropometría, genotipo y rendimiento deportivo / Artistic Swimming in Girls: Anthropometrics, Genotype and Athletic Performance

En cada deporte es importante optimizar peso y composición corporal y la genética y los datos antropométricos pueden influir en rendimiento deportivo y salud, sobre todo en deportistas menores. Este estudio analiza 60 nadadoras artísticas entre 9 y 17 años, divididas en tres grupos de edad: ≤12, 13-15 y 16-17 años. Se realizó un análisis de medidas antropométricas, edad de menarquia, genotipo relacionado con rendimiento (gen ACTN3) y resultados deportivos, con objetivo de relacionar estos parámetros entre sí en los grupos de edad. Las nadadoras de mayor edad mostraron tendencia a portar el genotipo heterocigoto RX de ACTN3. En este estudio, la práctica de este deporte podría tener impacto en índice de masa corporal, pliegue tricipital, peso y edad de menarquia. La mayor prevalencia del genotipo heterocigoto ACTN3 R577X podría ofrecer una ventaja, pero el rendimiento en competición de las nadadoras artísticas tuvo poca relación con sus medidas antropométricas. (AU)

In sport, optimizing weight and body composition is important for performance although an excessive drive for thinness can lead to diminished performance and health problems. This is especially important in the youngest athletes. This study examines 60 national competition-level Spanish artistic swimmers aged 9-17 years. Participants were divided into 3 categories: 12 years and under, 13-15 and 16-17 years. The data analysed were anthropometric measures, menarche age, genotype related to performance (gene ACTN3) and athletic performance. Relationships between athletic performance and anthropometric or genetic data were compared among the three age groups. Swimmers showed a tendency to carry the heterozygous genotype RX of the ACTN3 gene in the older age group. In this study, this sport could have an impact on body mass index, triceps skinfold, weight, menarche age, and selection of one genotype, but the performance in competition of the artistic swimmers had little linking to anthropometric measures. (AU)

Comparison of abdominal bloating severity between Irritable Bowel Syndrome patients with high and low levels of breath hydrogen excretion in a lactulose breath test.

BACKGROUND: There is growing evidence that gut flora plays a role in the development of Irritable Bowel Syndrome (IBS). Abdominal bloating is a common symptom in these patients and the severity of this symptom could be related to the variations in their fermentative profiles, obtained by measuring the levels of breath hydrogen excretion after lactulose ingestion. AIMS: Our objective was to determine the difference in abdominal bloating severity between IBS patients with high vs low levels of breath hydrogen excretion after lactulose administration. METHODS: Lactulose breath tests were carried out on IBS patients in our institution between July 2009 and August 2010. Patients were requested to fill out a validated questionnaire to assess the severity of their symptoms. Abdominal bloating severity score was compared among patients with high and low breath hydrogen levels. RESULTS: A total of 234 patients were enrolled. There was a statistically significant difference in the abdominal bloating severity score between groups: 7.0 (5.7-8.0) vs 6.5 (5.0-7.5), p=0.001. The comparison among IBS patients with constipation (IBS-C) in both groups also showed a statistically significant difference: 7.5 (6.0-8.5) vs 5.8 (3.5-7.2), p=0.0051. CONCLUSIONS: Those patients with a low level of breath hydrogen excretion after lactulose ingestion presented with significantly greater abdominal bloating than those with a high level of breath hydrogen excretion.

Evolutionary origins of the estrogen signaling system: insights from amphioxus.

Classically, the estrogen signaling system has two core components: cytochrome P450 aromatase (CYP19), the enzyme complex that catalyzes the rate limiting step in estrogen biosynthesis; and estrogen receptors (ERs), ligand activated transcription factors that interact with the regulatory region of target genes to mediate the biological effects of estrogen. While the importance of estrogens for regulation of reproduction, development and physiology has been well-documented in gnathostome vertebrates, the evolutionary origins of estrogen as a hormone are still unclear. As invertebrates within the phylum Chordata, cephalochordates (e.g., the amphioxus of the genus Branchiostoma) are among the closest invertebrate relatives of the vertebrates and can provide critical insight into the evolution of vertebrate-specific molecules and pathways. To address this question, this paper briefly reviews relevant earlier studies that help to illuminate the history of the aromatase and ER genes, with a particular emphasis on insights from amphioxus and other invertebrates. We then present new analyses of amphioxus aromatase and ER sequence and function, including an in silico model of the amphioxus aromatase protein, and CYP19 gene analysis. CYP19 shares a conserved gene structure with vertebrates (9 coding exons) and moderate sequence conservation (40% amino acid identity with human CYP19). Modeling of the amphioxus aromatase substrate binding site and simulated docking of androstenedione in comparison to the human aromatase shows that the substrate binding site is conserved and predicts that androstenedione could be a substrate for amphioxus CYP19. The amphioxus ER is structurally similar to vertebrate ERs, but differs in sequence and key residues of the ligand binding domain. Consistent with results from other laboratories, amphioxus ER did not bind radiolabeled estradiol, nor did it modulate gene expression on an estrogen-responsive element (ERE) in the presence of estradiol, 4-hydroxytamoxifen, diethylstilbestrol, bisphenol A or genistein. Interestingly, it has been shown that a related gene, the amphioxus "steroid receptor" (SR), can be activated by estrogens and that amphioxus ER can repress this activation. CYP19, ER and SR are all primarily expressed in gonadal tissue, suggesting an ancient paracrine/autocrine signaling role, but it is not yet known how their expression is regulated and, if estrogen is actually synthesized in amphioxus, whether it has a role in mediating any biological effects. Functional studies are clearly needed to link emerging bioinformatics and in vitro molecular biology results with organismal physiology to develop an understanding of the evolution of estrogen signaling. This article is part of a Special Issue entitled 'Marine organisms'.

Laboratory exposure to 17beta-estradiol fails to induce vitellogenin and estrogen receptor gene expression in the marine invertebrate Mytilus edulis.

To investigate the effect of estrogenic compounds on the marine mussel Mytilus edulis, an assay was developed to measure the expression of two vertebrate estrogen responsive genes-estrogen receptor (ER) and vitellogenin (VTG) genes. Expression was measured in M. edulis gonads following a 10-day exposure to 200 ng/l 17beta-estradiol (estradiol). The concentrations of esterified estradiol in mussel tissue increased 15-fold in a time-dependent manner-confirming uptake of the compound by the mussels, however there was no significant increase of free estradiol in mussel tissues during the exposure period. The ER and VTG mRNA levels in the gonads of both sexes were measured at days 1-3, 5, and 10 in control and exposed mussels. However, no significant change in the expression of either the ER or VTG genes was recorded at any of the sampled time points. The results suggest that either a regulatory mechanism exists in a mussel that is able to maintain constant levels of free estradiol by converting the excess estradiol into esterified products which may have reduced affinity for the estrogen receptor, or alternatively, that the ER and VTG genes are unresponsive to estrogens in these organisms. The significance of these findings in terms of the utility of ER and VTG as biomarkers of endocrine disruption in bivalve species is discussed.

Protein precipitation In Vitro as a measure of chemical-induced cytotoxicity: an EDIT sub-programme.

As a priority area of the Evaluation-Guided Development of In Vitro Toxicity and Toxicokinetic Tests (EDIT) programme, an in vitro protein precipitation (PP) assay was used on the 50 reference chemicals of the Multicentre Evaluation of In Vitro Cytotoxicity (MEIC) project, to confirm and extend the MEIC results. Dose-response curves were generated for only 30 of the chemicals, and the concentrations causing 10% (EC10) and 50% (EC50) protein precipitation versus the positive control were chosen as endpoints. The number of chemicals with a positive response increased to 46 when a new endpoint, the minimum effect concentration (MEC) that induces protein precipitation with respect to the negative control, was used. When the results were correlated with in vitro cytotoxicity in human cell lines, a similarly good correlation was found between the various endpoints of the PP assay at 5 hours and the 24-hour IC50 average cytotoxicity in human cell lines, even though the number of chemicals included in the correlation was larger for the MEC. Using the prediction error, the endpoint that gave the best correlation between the PP assay and human cell cytotoxicity was once more found to be the 5-hour MEC, and this was chosen for the PP assay. The sensitivity of the PP assay is lower than that of the in vitro cell-line cytotoxicity assay, possibly due to its shorter exposure period and because precipitation is the ultimate event in the sequence of a protein disturbance. It is expected that earlier denaturation steps would give better sensitivity. However, this simple, inexpensive and rapid assay could be useful in the early stages of testing chemicals.

Caenorhabditis elegans as an environmental monitor using DNA microarray analysis.

In order to assist in the identification of possible endocrine disrupting chemicals (EDC) in groundwater, we are developing Caenorhabolitis elegans as a high throughput bioassay system in which responses to EDC may be detected by gene expression using DNA microarray analysis. As a first step we examined gene expression patterns and vitellogenin responses of this organism to vertebrate steroids, in liquid culture. Western blotting showed the expected number and size of vitellogenin translation products after estrogen exposure. At 10(-9) M, vitellogenin decreased, but at 10(-7) and 10(-5), vitellogenin was increased. Testosterone (10(-5) M) increased the synthesis of vitellogenin, but progesterone-treated cultures (10(-5) M) had less vitellogenin. Using DNA microarray analysis, we examined the pattern of gene expression after progesterone (10(-5), 10(-7), and 10(-9) M), estrogen (10(-5) M), and testosterone (10(-9) M) exposure, with special attention to the traditional biomarker genes used in environmental studies [vitellogenin, cytochrome P450 (CYP), glutathione s-transferase (GST), metallothionein (MT), and heat shock proteins (HSP)]. GST and P450 genes were affected by estrogen (10(-5) M) and progesterone (10(-5) and 10(-7) M) treatments. For vitellogenin genes, estrogen treatment (10(-5) M) caused overexpression of the vit-2 and vit-6 genes (2.68 and 3.25 times, respectively). After progesterone treatment (10(-7) M), the vit-5 and vit-6 were down-regulated and vit-1 up-regulated (3.59-fold). Concentrations of testosterone and progesterone at 10(-9) M did not influence the expression of the vit, CYP, or GST genes. Although the analysis is incomplete, and low doses and combinations of EDC need to be tested, these preliminary results indicate C. elegans may be a useful laboratory and field model for screening EDC.

Toxicity and bioaccumulation of lead in marine protozoa communities.

The toxicity and bioaccumulation of lead has been studied using marine protozoa communities developed in laboratory microecosystems. The concentrations tested were 500 and 1000 micrograms.L-1 of lead as lead acetate. The protozoan was able to bioaccumulate 27.02-504 micrograms Pb.g-1 dry weight. Bacteria also bioaccumulated lead, but always to a lesser degree than protozoa. Lead caused a significant reduction in the density of protozoa, which could be an indirect response to the cellular increase of lead. On the other hand, the toxicant did not determine a decrease in the number of bacterial cells; this could be due to their capacity to bioaccumulate a lesser amount of lead, the increase in the number of dead cells, and the elimination of their predators by the toxicant. After 120 h, a recovery of the community was observed.

Multicenter evaluating of a commercially available PCR assay for diagnosing enterovirus infection in a panel of cerebrospinal fluid specimens.

Thirteen laboratories participated in blind tests of a panel of 20 coded cerebrospinal fluid specimens (7 uninfected samples, 3 samples infected with 1 50% tissue culture infective dose [TCID50]/0.1 ml [nonenterovirus strains], and 10 samples infected with 10, 1, or 0.1 TCID50/0.1 ml [three different enterovirus serotypes]) on the Amplicor enterovirus PCR assay (Roche Diagnostic Systems). The panel was also evaluated by in-house PCR (two nested-PCR and three one-step PCR assay) or tissue culture (eight laboratories). The viral load was shown to influence greatly the sensitivity of the assay. The average sensitivity of the Amplicor test ranged from 67 to 98% for viral titers of 1 to 10 TCID50/0.1 ml, respectively; titers of 0.1 TCID50/0.1 ml resulted in a sensitivity of only 16%. The overall specificity of the Amplicor test was 98%. The Amplicor assay compared favorably to the five in-house PCR tests (no significant difference in either sensitivity or specificity) and was much more sensitive than tissue culture (P < 0.001), even for high viral loads. It was easy to perform, rapid (about 6 h), well-standardized, and appeared to be suitable for the diagnosis of enterovirus meningitis on a routine basis in laboratories trained in molecular biology techniques.

The effects of cadmium on the successional stages of a freshwater protozoa community.

Microcosms containing protozoan were used to observe the differential effects of cadmium on the successional stages of a community. After 7, 14, and 21 days, 500 micrograms/liter cadmium was added. Some environmental parameters such as pH, conductivity, and nutrient levels affect metal toxicity. The effect of cadmium on diversity, density, and biomass was evident 48 hr after the addition of the metal. The pollutant caused a transition period in each treatment, of a different duration, followed by a recovery of the community. In both the control and the treatments, trophic structure was defined by bacterivore-detritivore, nonselective, and photoautotroph organisms.

Haemolytic uraemic syndrome associated with faecal cytotoxin and verotoxin neutralizing antibodies.

Forty-nine patients with a diagnosis of idiopathic haemolytic uraemic syndrome (HUS) were investigated to determine evidence of infection by verotoxin-producing Escherichia coli (VTEC). Free faecal cytotoxin active on Vero cells (VT) was detected in 15 out of 49 patients (31%). Seroconversion or high titres of VT-neutralizing antibodies were detected in 11 out of 18 patients (61%). The results of the present study suggest an association between HUS and infection by VTEC.

[Comparison of the latex agglutination method with the hemagglutination inhibition test in the detection of antibodies against rubella virus]. / Comparación del método de aglutinación en latex con la inhibición de la hemaglutinación en la detección de anticuerpos contra el virus rubéola.

Rubella virus antibodies were measured in 85 sera from pregnant women by using a new latex test, and the results were compared with those obtained by using hemagglutination inhibition. The sensitivity of the latex test was 98.4%, specificity was 66.6% and the predictive value of a positive result was 90%. The latex test is a simple test and has much shorter reaction time than that of the hemagglutination inhibition.

Comparación del método de aglutinación en latex con la inhibición de la hemaglutinación en la detección de anticuerpos contra el virus rubéola. / [Comparison of the latex agglutination method with the hemagglutination inhibition test in the detection of antibodies against rubella virus]

Rubella virus antibodies were measured in 85 sera from pregnant women by using a new latex test, and the results were compared with those obtained by using hemagglutination inhibition. The sensitivity of the latex test was 98.4

, specificity was 66.6

and the predictive value of a positive result was 90

. The latex test is a simple test and has much shorter reaction time than that of the hemagglutination inhibition.