Association between serum 25-hydroxyvitamin D and prostate-specific antigen: a retrospective study in men without prostate pathology.

Objectives: Recently, vitamin D status has been associated with prostate cancer risk. However, some studies argue that there is no association of vitamin D with prostate cancer risk and serum prostate-specific antigen (PSA) concentrations. No clear conclusions can be drawn from the studies found in the literature. Our aim was to assess the relationship between PSA and 25-hydroxyvitamin D [25(OH)D]. Methods: We selected 415 individuals without prostate pathologies and subgroups were generated according to age and 25(OH)D. Statistical analyses were performed using Shapiro-Wilk test, Student's t and ANOVA tests, and Pearson's correlation. Besides, the minimum sample size needed to obtain statistically significant results between groups according to 25(OH)D concentration was calculated and a Student's t-test for paired samples was performed to study individuals with two PSA measurements over time, where 25(OH)D concentration increased or decreased more than 25 %. Results: We observed a slight correlation between age and PSA concentration (r=0.379, p<0.001). However, we found no significant differences when we compared PSA concentrations between groups according to 25(OH)D concentrations (p=0.891): 1.25 ± 1.32 µg/L (group with 25(OH)D<50 nmol/L) and 1.17 ± 0.90 (group with 25(OH)D≥50 nmol/L). Pearson's correlation coefficient was close to 0. The minimum samples size to obtain statistically significant results was 815,346 men, and we observed no differences in PSA concentrations in individuals with two measurements. Conclusions: Our findings show no association in men without prostate pathologies, based on 25(OH)D levels.

The relationship between morphology and flight in Drosophila: a study of two pairs of sibling species from a natural population.

Insect flight is a complex trait involved in different behaviors, from the search for sexual partners, food, or breeding sites. Many studies have postulated the adaptive advantages of certain morphological traits in relation to increased flight capacity, such as low values of wing loading or high values of wing:thorax ratio and wing-aspect ratio. However, few studies have evaluated the relationship between variables related to flight and morphological traits in Drosophila. This work aimed to study morphological traits in males and females of two pairs of sibling species: Drosophila buzzatii Patterson and Wheeler-Drosophila koeferae Fontdevila and Wasserman, and Drosophila melanogaster Meigen-Drosophila simulans Sturtevant, and to analyze its relationship with flight. We detected the highest proportion of flight time in D. koepferae and D. simulans compared to D. buzzatii and D. melanogaster, respectively. Our results also revealed sexual dimorphism, with males exhibiting a higher proportion of flight time than females. Surprisingly, we did not find a general pattern to explain the relationship between morphology and the proportion of flight time because associations varied depending upon the analyses (considering all groups together or each sex-species combination separately). Moreover, these associations explained a low percentage of variation, suggesting that other nonmorphological components related to flight, such as physiological variables, should be taken into account. This work allowed us to show the variability and complexity of an aspect of flight, suggesting that the adaptive role of the morphological traits studied might have been overestimated.

Proteome changes in pepper (Capsicum annuum L.) leaves induced by the green peach aphid (Myzus persicae Sulzer).

BACKGROUND: Aphid attack induces defense responses in plants activating several signaling cascades that led to the production of toxic, repellent or antinutritive compounds and the consequent reorganization of the plant primary metabolism. Pepper (Capsicum annuum L.) leaf proteomic response against Myzus persicae (Sulzer) has been investigated and analyzed by LC-MS/MS coupled with bioinformatics tools. RESULTS: Infestation with an initially low density (20 aphids/plant) of aphids restricted to a single leaf taking advantage of clip cages resulted in 6 differentially expressed proteins relative to control leaves (3 proteins at 2 days post-infestation and 3 proteins at 4 days post-infestation). Conversely, when plants were infested with a high density of infestation (200 aphids/plant) 140 proteins resulted differentially expressed relative to control leaves (97 proteins at 2 days post-infestation, 112 proteins at 4 days post-infestation and 105 proteins at 7 days post-infestation). The majority of proteins altered by aphid attack were involved in photosynthesis and photorespiration, oxidative stress, translation, protein folding and degradation and amino acid metabolism. Other proteins identified were involved in lipid, carbohydrate and hormone metabolism, transcription, transport, energy production and cell organization. However proteins directly involved in defense were scarce and were mostly downregulated in response to aphids. CONCLUSIONS: The unexpectedly very low number of regulated proteins found in the experiment with a low aphid density suggests an active mitigation of plant defensive response by aphids or alternatively an aphid strategy to remain undetected by the plant. Under a high density of aphids, pepper leaf proteome however changed significantly revealing nearly all routes of plant primary metabolism being altered. Photosynthesis was so far the process with the highest number of proteins being regulated by the presence of aphids. In general, at short times of infestation (2 days) most of the altered proteins were upregulated. However, at longer times of infestation (7 days) the protein downregulation prevailed. Proteins involved in plant defense and in hormone signaling were scarce and mostly downregulated.

Phytohormone responses in pepper (Capsicum annuum L.) leaves under a high density of aphid infestation.

The time course response of selected phytohormones has been evaluated in sweet pepper plants (Capsicum annuum L.) submitted to a high density (200 aphids/plant) of aphid (Myzus persicae Sulzer) infestation. Abscisic acid (ABA), salicylic acid (SA), indole-3-acetic acid (IAA), and jasmonates (JAs), including jasmonic acid (JA), jasmonoyl-l-isoleucine (JA-Ile), and cis-OPDA have been simultaneously identified and quantitated by UHPLC-MS/MS in pepper leaf tissue harvested at 3, 8 hours post-infestation (hpi), 1, 2, 4 and 7 days post-infestation (dpi). Infested plants showed a reduction in stem length at 7 dpi and in the number of leaves and leaf width from 4 dpi onwards. JA and JA-Ile significantly increased very early (from 3 hpi) while SA only accumulated at 7 dpi. Despite the high density of infestation, the aphid-induced accumulation of JAs was much lower than the burst typically induced by chewing herbivores. On the other side, ABA peaked in aphid-infested plants at 2 and 4 dpi, while IAA content did not change significantly at any time point. Growth inhibition may be partially explained by the high levels of JAs found in aphid-infested plants. The possibility that the obtained results support the hypothesis of the aphid manipulation of plant metabolism is discussed.

Contrasting levels of genotype by environment interaction for life history and morphological traits in invasive populations of Zaprionus indianus (Diptera: Drosophilidae).

It has been demonstrated that phenotypic plasticity and genotype by environment interaction are important for coping with new and heterogeneous environments during invasions. Zaprionus indianus Gupta (Diptera: Drosophilidae) is an Afrotropical invasive fly species introduced to the South American continent in 1999. This species is generalist and polyphagous, since it develops and feeds in several different fruit species. These characteristics of Z. indianus suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion process. In this sense, our aim was to investigate the role of genetic variation for phenotypic plasticity (genotype by environment interaction) in Z. indianus invasion of the South American continent. Specifically, we quantified quantitative genetic variation and genotype by environment interactions of morphological and life history traits in different developmental environments, that is, host fruits. This was done in different populations in the invasive range of Z. indianus in Argentina. Results showed that Z. indianus populations have considerable amounts of quantitative genetic variation. Also, genotype by environment interactions was detected for the different traits analyzed in response to the different developmental environments. Interestingly, the amounts and patterns of these parameters differed between populations. We interpreted these results as the existence of differences in evolutionary potential between populations that have an important role in the short- and long-term success of the Z. indianus invasion process.

Local and systemic hormonal responses in pepper (Capsicum annuum L.) leaves under green peach aphid (Myzus persicae Sulzer) infestation.

This study examined the temporal changes in the leaf content of defence-involved phytohormones in pepper (Capsicum annuum L.) plants responding to the green peach aphid (Myzus persicae Sulzer) infestation, at both local and systemic level. Aphid infestation did not alter the content of cis-12-oxo-phytodienoic acid, the jasmonic acid (JA) precursor, even though endogenous levels of JA and its bioactive isoleucine-conjugated form (JA-Ile) significantly increased from 8 to 96 h in local infested leaves. Systemic effects in jasmonates were only showed at 48 h for JA, and 8 and 48 h in the case of JA-Ile. SA accumulated only in local infested leaves after 96 h of infestation, when the level of JA-Ile decreased in these leaves. This suggests a possible antagonistic interaction between JA and SA pathways, although other pathways may be also involved. Endogenous level of indole-3-acetic acid was higher in systemic relative to local infested leaves at 3 and 24 h, although no significant changes in its content were found compared to control leaves. Abscisic acid content was lower in local infested relative to control leaves at 24 h, but was higher at 48 h when it also increased systemically. The possible roles of the studied phytohormones in plant defence responses against aphids are discussed.

Changes in the free amino acid composition of Capsicum annuum (pepper) leaves in response to Myzus persicae (green peach aphid) infestation. A comparison with water stress.

Amino acids play a central role in aphid-plant interactions. They are essential components of plant primary metabolism, function as precursors for the synthesis of defense-related specialized metabolites, and are major growth-limiting nutrients for aphids. To quantify changes in the free amino acid content of pepper (Capsicum annuum L.) leaves in response to green peach aphid (Myzus persicae Sulzer) feeding, plants were infested with a low (20 aphids/plant) or a high (200 aphids/plant) aphid density in time-course experiments ranging from 3 hours to 7 days. A parallel experiment was conducted with pepper plants that had been subjected to water stress. Factor Analysis of Mixed Data revealed a significant interaction of time x density in the free amino acid response of aphid-infested leaves. At low aphid density, M. persicae did not trigger a strong response in pepper leaves. Conversely, at high density, a large increase in total free amino acid content was observed and specific amino acids peaked at different times post-infestation. Comparing aphid-infested with water-stressed plants, most of the observed differences were quantitative. In particular, proline and hydroxyproline accumulated dramatically in response to water stress, but not in response to aphid infestation. Some additional differences and commonalities between the two stress treatments are discussed.

Drosophila wing modularity revisited through a quantitative genetic approach.

To predict the response of complex morphological structures to selection it is necessary to know how the covariation among its different parts is organized. Two key features of covariation are modularity and integration. The Drosophila wing is currently considered a fully integrated structure. Here, we study the patterns of integration of the Drosophila wing and test the hypothesis of the wing being divided into two modules along the proximo-distal axis, as suggested by developmental, biomechanical, and evolutionary evidence. To achieve these goals we perform a multilevel analysis of covariation combining the techniques of geometric morphometrics and quantitative genetics. Our results indicate that the Drosophila wing is indeed organized into two main modules, the wing base and the wing blade. The patterns of integration and modularity were highly concordant at the phenotypic, genetic, environmental, and developmental levels. Besides, we found that modularity at the developmental level was considerably higher than modularity at other levels, suggesting that in the Drosophila wing direct developmental interactions are major contributors to total phenotypic shape variation. We propose that the precise time at which covariance-generating developmental processes occur and/or the magnitude of variation that they produce favor proximo-distal, rather than anterior-posterior, modularity in the Drosophila wing.

The Down syndrome-related protein kinase DYRK1A phosphorylates p27(Kip1) and Cyclin D1 and induces cell cycle exit and neuronal differentiation.

A fundamental question in neurobiology is how the balance between proliferation and differentiation of neuronal precursors is maintained to ensure that the proper number of brain neurons is generated. Substantial evidence implicates DYRK1A (dual specificity tyrosine-phosphorylation-regulated kinase 1A) as a candidate gene responsible for altered neuronal development and brain abnormalities in Down syndrome. Recent findings support the hypothesis that DYRK1A is involved in cell cycle control. Nonetheless, how DYRK1A contributes to neuronal cell cycle regulation and thereby affects neurogenesis remains poorly understood. In the present study we have investigated the mechanisms by which DYRK1A affects cell cycle regulation and neuronal differentiation in a human cell model, mouse neurons, and mouse brain. Dependent on its kinase activity and correlated with the dosage of overexpression, DYRK1A blocked proliferation of SH-SY5Y neuroblastoma cells within 24 h and arrested the cells in G1 phase. Sustained overexpression of DYRK1A induced G0 cell cycle exit and neuronal differentiation. Furthermore, we provide evidence that DYRK1A modulated protein stability of cell cycle-regulatory proteins. DYRK1A reduced cellular Cyclin D1 levels by phosphorylation on Thr286, which is known to induce proteasomal degradation. In addition, DYRK1A phosphorylated p27(Kip1) on Ser10, resulting in protein stabilization. Inhibition of DYRK1A kinase activity reduced p27(Kip1) Ser10 phosphorylation in cultured hippocampal neurons and in embryonic mouse brain. In aggregate, these results suggest a novel mechanism by which overexpression of DYRK1A may promote premature neuronal differentiation and contribute to altered brain development in Down syndrome.

Actividad tripanocida y antioxidante in vitro de los extractos etanólicos de Caesalpinia pluviosa DC. y Astronium urundeuva (Allemâo) Engl. / Trypanocidal and antioxidant in vitro activities of ethanolic extracts from Caesalpinia pluviosa DC. and Astronium urundeuva (Allemâo) Engl

Caesalpinia pluviosa DC yAstronium urundeuva (Allemâo) Engl. , son plantas medicinales de uso tradicional en Bolivia. Para determinar la actividad tripanocida y antioxidante in vitro de los extractos etanólicos de estas especies vegetales, se realizó la medición de la inhibición del desarrollo in vitro de tripomastigotes de Trypanosoma cruzi, clon CL Brener. Los métodos antioxidantes fueron 1,1-difenil-2-picril-hidrazil (DPPH) y 2,2-azino-bis (3- etilbenzo-tiazolina-6-sulfónico ácido) diamonio sal (ABTS). El extracto etanólico de la corteza de Caesalpinia pluviosa DC tuvo la mayor actividad tripanocida (CI50 = 55 µg/ml +7,07) y antioxidante (CI50 = 0,166mg/ml por el método ABTS y CI50 = 1,30 por el método DPPH). En conclusión, este estudio revela que los extractos de Caesalpinia pluviosa DC y Astronium urundeuva (Allemâo) Engl., tienen un efecto tripanocida y antioxidante in vitro, justificando el uso tradicional de la planta y constituyéndose en excelentes candidatos para completar estudios biológicos in vivo y químicos. Esta asociación de actividad antioxidante-tripanocida, es una nueva perspectiva para el tratamiento de la enfermedad de Chagas. (AU)

Actividad tripanocida in vitro e in vivo de extractos etanólicos de algunas plantas medicinales bolivianas / In vitro and in vivo trypanocidal activity, of ethanolic extracts from some bolivian medicinal plants

A 100 años del descubrimiento de la enfermedad de Chagas, aun no existen drogas que satisfagan completamente. Los extractos de plantas medicinales son una posibilidad de obtener nuevos compuestos que sean activos contra Trypanosoma cruzi. Se evaluó la actividad tripanocida in vitro sobre las formas tripomastigotes de ocho extractos etanólicos provenientes de 4 plantas medicinales bolivianas. El extracto etanólico de la corteza de Anacardium occidentale fue el más activo in vitro (CI50= 200 µg/ml), seguido de las hojas de Bowdichia virgilioides (350 µg/ml). A. occidentale, B. virgilioides y Senna reticulata, no son eficaces en la fase aguda de la enfermedad de Chagas en el modelo murino. (AU)

Parásitos intestinales e niños de madres internas en le Centro de Orientación Femenina de Obrajes, La Paz Bolivia: alta prevalencia de Blastocystis hominis / Intestinal parasites in children of incarcerated mothers of Center at the Feminine Orientation of Obrajes, La Paz Bolivia: high prevalence of Blastocystis hominis

Las enteroparasitosis, lejos de ser erradicadas, persisten con mayor intensidad. El objetivo de este estudio fue evaluar la prevalencia de enteroparásitos en niños residentes en el Centro de Orientación Femenina de Obrajes, La Paz, Bolivia, en le periodo 2008.

Papulonodular mucinosis in systemic lupus erythematosus.

A 41-year-old man with systemic and serological manifestations of systemic lupus erythematosus presented with a diffuse eruption comprising annular plaques. Histopathology revealed diffuse deposition of mucin throughout the dermis, consistent with papulonodular mucinosis. This uncommon entity of unclear pathogenesis has been described in systemic lupus erythematosus, discoid lupus erythematosus, and subacute cutaneous lupus erythematosus.