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Sample records for nothofagus pumilio bajo

  1. Differential hypogeous sporocarp production from Nothofagus dombeyi and N. pumilio forests in southern Argentina.

    PubMed

    Nouhra, Eduardo R; Urcelay, Carlos; Longo, M Silvana; Fontenla, Sonia

    2012-01-01

    Mycorrhizal fungi that form hypogeous sporocarps are an important component of the temperate forest soil community. In many regions, such as the Nothofagus forest in the Patagonian Andes, this group of fungi has been poorly studied. Here we examined the spring and autumn community composition of "sequestrate fungi", based on sporocarp production in pure forests of Nothofagus dombeyi (evergreen) and N. pumilio (deciduous). We investigated the possible relationships between these communities and environmental factors over 2 y. The rarefaction curves and the minimal richness estimates converged at nearly the same level for each forest type, and the asymptotes suggested that the sampling effort was sufficient to capture most of the hypogeous sporocarp richness in these forest stands. In total 27 species were recovered. Basidiomycota, Ascomycota and Glomeromycota respectively accounted for nine, two and one genera. Species richness of hypogeous sporocarps varied in relation to forest type but not to season (fall and spring), whereas sporocarp biomass varied according to an interaction between season and forest type. Species richness and sporocarp biomass were positively correlated with rainfall and negatively correlated with altitude. In addition sporocarp species richness was positively related to number of trees per transect. We found that two different forest stands, each dominated by different species of Nothofagus, exhibited different hypogeous sporocarp communities. PMID:21914828

  2. Differential hypogeous sporocarp production from Nothofagus dombeyi and N. pumilio forests in southern Argentina.

    PubMed

    Nouhra, Eduardo R; Urcelay, Carlos; Longo, M Silvana; Fontenla, Sonia

    2012-01-01

    Mycorrhizal fungi that form hypogeous sporocarps are an important component of the temperate forest soil community. In many regions, such as the Nothofagus forest in the Patagonian Andes, this group of fungi has been poorly studied. Here we examined the spring and autumn community composition of "sequestrate fungi", based on sporocarp production in pure forests of Nothofagus dombeyi (evergreen) and N. pumilio (deciduous). We investigated the possible relationships between these communities and environmental factors over 2 y. The rarefaction curves and the minimal richness estimates converged at nearly the same level for each forest type, and the asymptotes suggested that the sampling effort was sufficient to capture most of the hypogeous sporocarp richness in these forest stands. In total 27 species were recovered. Basidiomycota, Ascomycota and Glomeromycota respectively accounted for nine, two and one genera. Species richness of hypogeous sporocarps varied in relation to forest type but not to season (fall and spring), whereas sporocarp biomass varied according to an interaction between season and forest type. Species richness and sporocarp biomass were positively correlated with rainfall and negatively correlated with altitude. In addition sporocarp species richness was positively related to number of trees per transect. We found that two different forest stands, each dominated by different species of Nothofagus, exhibited different hypogeous sporocarp communities.

  3. Regeneration of Nothofagus pumilio [Poepp. et Endl.] Krasser forests after five years of seed tree cutting.

    PubMed

    Rosenfeld, J M; Navarro Cerrillo, R M; Guzman Alvarez, J R

    2006-01-01

    Nothofagus pumilio [Poepp. et Endl.] Krasser is a deciduous tree species that grows in Chile and adjacent Argentina between 36 and 56 degrees S, often forming the Andean tree line. Silvicultural systems proposed for this species integrate both regeneration and intermediate level operations in an orderly process for managing forest stands. The seed-tree method of regeneration has been used to manage even-aged stands of this species. This paper investigates the effect of seed tree cuttings on the regeneration of Nothofagus pumilio [Poepp. et Endl.] Krasser forest located in the Magallanes region (Chile). The studied forest was managed on an even-aged basis using a seed tree silvicultural system for regeneration with an intensity of cutting of 65-70% of the basal area and a minimum of 15 dominant lenga trees per hectare retained. A regeneration inventory sampling was used to quantify regeneration attributes in the study area. Regeneration was found to be significantly affected by the seed tree cuttings. In fact, the number of established individuals rose from 0.39 to 26.7 plants m(-2) pre-harvest to 9.2-21.5 plants m(-2) post-harvest, depending on the particular development stage. Total regeneration ranged from 9.5 to 48.2 plants m(-2). The number of plants established over the period 1992-1997 was related to the residual basal area, coverage and number of trees. However, mean tree height was not significantly related to any regeneration variable. Significant variables were used to establish a regeneration prediction model using single and multiple linear equations (R2<0.418). Consequently, the seed tree method of regeneration can be considered feasible for commercially valuable lenga forests, although this method, in its strictest application, will create many large, irregularly shaped, even-aged groups.

  4. Are the oxygen isotopic compositions of Fitzroya cupressoides and Nothofagus pumilio cellulose promising proxies for climate reconstructions in northern Patagonia?

    NASA Astrophysics Data System (ADS)

    Lavergne, Aliénor; Daux, Valérie; Villalba, Ricardo; Pierre, Monique; Stievenard, Michel; Vimeux, Françoise; Srur, Ana Marina

    2016-03-01

    Tree ring δ18O chronologies from two native species (Fitzroya cupressoides and Nothofagus pumilio) in northern Patagonia were developed to assess their potential for paleoclimate reconstructions. The five annually resolved cellulose δ18O chronologies (two for F. cupressoides and three for N. pumilio) are located on the Andes along the steep west-to-east precipitation gradient. Over the common 60 years long interval, the five site-δ18Ocell chronologies exhibit a strong common signal as indicated by the significant mean intercorrelation (r = 0.61, p < 0.05) and the high percentage (65%) of total variance explained by the first empirical orthogonal function. Although correlation analyses reveal that the two mean species-δ18Ocell chronologies are mainly modulated by December-May temperature, the N. pumilio chronology shows a greater sensitivity to record temperature variations (r = 0.57, p < 0.05). The δ18Ocell of N. pumilio contains a regional temperature signal representative of a large area in southern South America under the influence of the Southern Annular Mode. This study indicates that δ18Ocell in N. pumilio is a promising proxy to reconstruct past variations in temperature in South America south of 38°S.

  5. Foliar anatomical and morphological variation in Nothofagus pumilio seedlings under controlled irradiance and soil moisture levels.

    PubMed

    Ivancich, Horacio S; Lencinas, María V; Pastur, Guillermo J Martínez; Esteban, Rosina M Soler; Hernández, Luis; Lindstrom, Ivone

    2012-05-01

    Foliar anatomy and morphology are strongly related to physiological performance; therefore, phenotypic plasticity in leaves to variations in environmental conditions, such as irradiance and soil moisture availability, can be related to growth rate and survivorship, mainly during critical growth phases, such as establishment. The aim of this work was to analyze changes in the foliar internal anatomy (tissue proportions and cell dimensions) and external morphology (leaf length, width and area) of Nothofagus pumilio (Poepp. et Endl.) Krasser seedlings growing in a greenhouse under controlled irradiance (three levels) and soil moisture (two levels) during one growing season (measured three times), and to relate them to physiological traits. Three irradiance levels (4, 26 and 64% of the natural incident light) and two soil moisture levels (40 and 80% soil capacity) were evaluated during November, January and March. Internal foliar anatomy of seedlings was analyzed using digital photographs of histological cuttings, while leaf gross morphology was measured using digital calipers and image analysis software. Most internal anatomical variables presented significant differences under different irradiance levels during the growing season, but differences were not detected between soil moisture levels. Palisade parenchyma was the tissue most sensitive to irradiance levels, and high irradiance levels (64% natural incident light) produced greater values in most of the internal anatomical variables than lower irradiance levels (4-24% natural incident light). Complementarily, larger leaves were observed in medium and low irradiance levels, as well as under low soil moisture levels (40% soil capacity). The relationship of main results with some eco-physiological traits was discussed. Foliar internal anatomical and external morphological plasticity allows quick acclimation of seedlings to environmental changes (e.g., during harvesting). These results can be used to propose new

  6. Multi-stemmed trees of Nothofagus pumilio second-growth forest in Patagonia are formed by highly related individuals

    PubMed Central

    Till-Bottraud, Irène; Fajardo, Alex; Rioux, Delphine

    2012-01-01

    Background and Aims Multi-stemmed trees (tree clusters) in Nothofagus pumilio, a dominant tree species in Patagonia, are very uncommon and are restricted to the edge of second-growth forests following human-provoked fires. No vegetative reproduction has been reported so far. The genetic structure of multi-stemmed trees of this species was investigated and it was hypothesized that genets within a cluster were more closely related than average in the population. Methods Fifteen clusters (composed of at least three purported stems) and 15 single trees were sampled at the edge of a second-growth forest and genotyped using two amplified fragment length polymorphism (AFLP) primer pairs. We obtained 119 polymorphic markers that allowed clonality to be determined, together with sibship structure and relatedness among samples. Key Results Clonality was detected in seven clusters but all clusters had at least two different genotypes. Full sibs were found exclusively within clusters and in all clusters. Within a cluster, stems that were not identified as full sibs were often half sibs. Relatedness values for the full sibs and half sibs were higher than the theoretical values of 0·5 and 0·25 but the relatedness between clusters was very low. Conclusions Tree clusters that are merged at the edge of the second-growth forest of N. pumilio are composed of stems of the same genotype and of other genotypes that are highly related (but not always). It is suggested that this peculiar genetic structure results from a combination of several causes, including selection for merging of related individuals. PMID:22782238

  7. No evidence of carbon limitation with tree age and height in Nothofagus pumilio under Mediterranean and temperate climate conditions

    PubMed Central

    Piper, Frida I.; Fajardo, Alex

    2011-01-01

    Background and Aims Trees universally decrease their growth with age. Most explanations for this trend so far support the hypothesis that carbon (C) gain becomes limited with age; though very few studies have directly assessed the relative reductions of C gain and C demand with tree age. It has also been suggested that drought enhances the effect of C gain limitation in trees. Here tests were carried out to determine whether C gain limitation is causing the growth decay with tree age, and whether drought accentuates its effect. Methods The balance between C gain and C demand across tree age and height ranges was estimated. For this, the concentration of non-structural carbohydrates (NSCs) in stems and roots of trees of different ages and heights was measured in the deciduous temperate species Nothofagus pumilio. An ontogenetic decrease in NSCs indicates support for C limitation. Furthermore, the importance of drought in altering the C balance with ontogeny was assessed by sampling the same species in Mediterranean and humid climate locations in the southern Andes of Chile. Wood density (WD) and stable carbon isotope ratios (δ13C) were also determined to examine drought constraints on C gain. Key Results At both locations, it was effectively found that tree growth ultimately decreased with tree age and height. It was found, however, that NSC concentrations did not decrease with tree age or height when WD was considered, suggesting that C limitation is not the ultimate mechanism causing the age/height-related declining tree growth. δ13C decreased with tree age/height at the Mediterranean site only; drought effect increased with tree age/height, but this pattern was not mirrored by the levels of NSCs. Conclusions The results indicate that concentrations of C storage in N. pumilio trees do not decrease with tree age or height, and that reduced C assimilation due to summer drought does not alter this pattern. PMID:21852277

  8. Effectiveness of fencing and hunting to control Lama guanicoe browsing damage: Implications for Nothofagus pumilio regeneration in harvested forests.

    PubMed

    Martínez Pastur, Guillermo; Soler, Rosina; Ivancich, Horacio; Lencinas, María V; Bahamonde, Héctor; Peri, Pablo L

    2016-03-01

    Browsing damage by native ungulates is often to be considered one of the reasons of regeneration failure in Nothofagus pumilio silvicultural systems. Fencing and hunting in forests at regeneration phase have been proposed to mitigate browsing effects. This study aims to determine effectiveness of these control methods in harvested forests, evaluating browsing damage over regeneration, as well as climate-related constraints (freezing or desiccation). Forest structure and regeneration plots were established in two exclosures against native ungulates (Lama guanicoe) by wire fences in the Chilean portion of Tierra del Fuego island, where tree regeneration density, growth, abiotic damage and quality (multi-stems and base/stem deformation) were assessed. Exclosures did not influence regeneration density (at the initial stage with < 1.3 m high, and at the advanced stage with >1.3 m high). However, sapling height at 10-years old was significantly lower outside (40-50 cm high) than inside exclosures (80-100 cm), and also increased their annual height growth, probably as a hunting effect. Likewise, quality was better inside exclosures. Alongside browsing, abiotic conditions negatively influenced sapling quality in the regeneration phase (20%-28% of all seedlings), but greatly to taller plants (as those from inside exclosure). This highlights the importance of considering climatic factors when analysing browsing effects. For best results, control of guanaco in recently harvested areas by fencing should be applied in combination with a reduction of guanaco density through continuous hunting. The benefits of mitigation actions (fencing and hunting) on regeneration growth may shorten the regeneration phase period in shelterwood cutting forests (30-50% less time), but incremental costs must be analysed in the framework of management planning by means of long-term studies. PMID:26708647

  9. Effectiveness of fencing and hunting to control Lama guanicoe browsing damage: Implications for Nothofagus pumilio regeneration in harvested forests.

    PubMed

    Martínez Pastur, Guillermo; Soler, Rosina; Ivancich, Horacio; Lencinas, María V; Bahamonde, Héctor; Peri, Pablo L

    2016-03-01

    Browsing damage by native ungulates is often to be considered one of the reasons of regeneration failure in Nothofagus pumilio silvicultural systems. Fencing and hunting in forests at regeneration phase have been proposed to mitigate browsing effects. This study aims to determine effectiveness of these control methods in harvested forests, evaluating browsing damage over regeneration, as well as climate-related constraints (freezing or desiccation). Forest structure and regeneration plots were established in two exclosures against native ungulates (Lama guanicoe) by wire fences in the Chilean portion of Tierra del Fuego island, where tree regeneration density, growth, abiotic damage and quality (multi-stems and base/stem deformation) were assessed. Exclosures did not influence regeneration density (at the initial stage with < 1.3 m high, and at the advanced stage with >1.3 m high). However, sapling height at 10-years old was significantly lower outside (40-50 cm high) than inside exclosures (80-100 cm), and also increased their annual height growth, probably as a hunting effect. Likewise, quality was better inside exclosures. Alongside browsing, abiotic conditions negatively influenced sapling quality in the regeneration phase (20%-28% of all seedlings), but greatly to taller plants (as those from inside exclosure). This highlights the importance of considering climatic factors when analysing browsing effects. For best results, control of guanaco in recently harvested areas by fencing should be applied in combination with a reduction of guanaco density through continuous hunting. The benefits of mitigation actions (fencing and hunting) on regeneration growth may shorten the regeneration phase period in shelterwood cutting forests (30-50% less time), but incremental costs must be analysed in the framework of management planning by means of long-term studies.

  10. Living on the edge: adaptive and plastic responses of the tree Nothofagus pumilio to a long-term transplant experiment predict rear-edge upward expansion.

    PubMed

    Mathiasen, Paula; Premoli, Andrea C

    2016-06-01

    Current climate change affects the competitive ability and reproductive success of many species, leading to local extinctions, adjustment to novel local conditions by phenotypic plasticity or rapid adaptation, or tracking their optima through range shifts. However, many species have limited ability to expand to suitable areas. Altitudinal gradients, with abrupt changes in abiotic conditions over short distances, represent "natural experiments" for the evaluation of ecological and evolutionary responses under scenarios of climate change. Nothofagus pumilio is the tree species which dominates as pure stands the montane forests of Patagonia. We evaluated the adaptive value of variation in quantitative traits of N. pumilio under contrasting conditions of the altitudinal gradient with a long-term reciprocal transplant experimental design. While high-elevation plants show little response in plant, leaf, and phenological traits to the experimental trials, low-elevation ones show greater plasticity in their responses to changing environments, particularly at high elevation. Our results suggest a relatively reduced potential for evolutionary adaptation of high-elevation genotypes, and a greater evolutionary potential of low-elevation ones. Under global warming scenarios of forest upslope migration, high-elevation variants may be outperformed by low-elevation ones during this process, leading to the local extinction and/or replacement of these genotypes. These results challenge previous models and predictions expected under global warming for altitudinal gradients, on which the leading edge is considered to be the upper treeline forests. PMID:26868524

  11. Pumilio genes from the Platyhelminthes.

    PubMed

    Koziol, Uriel; Marín, Monica; Castillo, Estela

    2008-01-01

    Pumilio proteins are proposed to have a conserved primordial function in the maintenance of proliferation in stem cells through post-transcriptional regulation. In this work, a search for pumilio homology domain (PUM-HD) sequences of pumilio genes from several Platyhelminthes species was performed, including representatives form Cestoda, Trematoda and Tricladida. Only one PUM-HD sequence was found in each triclad species; however, two PUM-HD homologues were found in all the parasitic species. These sequences formed two clearly separated clades: PlatyPum1, with sequences from all species, and PlatyPum2, composed exclusively of neodermatan sequences. Therefore, at least one duplication of the pumilio gene must have occurred before the divergence of cestodes and trematodes. Further duplications of PUM-HD were found in Fasciola hepatica, but these consist of retropseudogenes. This is the first comparative analysis of PUM-HD sequences in the Platyhelminthes and, more generally, in any lophotrochozoan phylum.

  12. Low temperature responses of Nothofagus dombeyi and Nothofagus nitida, two evergreen species from south central Chile.

    PubMed

    Reyes-Díaz, M; Alberdi, M; Piper, F; Bravo, L A; Corcuera, L J

    2005-11-01

    Nothofagus dombeyi (Mirb.) Blume and Nothofagus nitida (Phil.) Krasser are closely related evergreen trees native to south central Chile. Nothofagus dombeyi is a pioneer in habitats subject to high daytime irradiances and nighttime freezing temperatures and has a wider altitudinal and latitudinal distribution than N. nitida, which is restricted to more oceanic climates. We postulated that N. dombeyi has a greater cold-acclimation capacity, expressed as a greater capacity to maintain a functional photosynthetic apparatus at low temperatures, than N. nitida. Because cold-acclimation may be related to the accumulation of cryoprotective substances, we investigated relationships between ice nucleation temperature (IN), freezing temperature (FT), and the temperature causing injury to 50% of the leaf tissues (LT(50)) on the one hand, and concentrations of total soluble carbohydrates (TSC), starch and proline on the other hand. Observations were made throughout a seasonal cycle in adults and seedlings in the field and in seedlings in the laboratory under cold-acclimation inductive and non-inductive conditions. In adults, LT(50) values were lower in N. dombeyi than in N. nitida, suggesting that N. dombeyi is the more frost tolerant species. Adults of both species tolerated freezing in autumn and winter but not in spring and summer. In the fall and winter, seedlings of N. dombeyi had a much lower LT(50) than those of N. nitida. Nothofagus nitida seedlings, in autumn and winter, exhibited freezing avoidance mechanisms. Although elevated TSC and proline concentrations may contribute to freezing tolerance in adults of both species, an increase in proline concentration is unlikely to be the dominant frost tolerance response in adults because proline concentrations were higher in N. nitida than in N. dombeyi. In seedlings, however, there were large differences in proline accumulation between species that may account for the difference between them in freezing tolerance. Starch

  13. Heterospecific Acoustic Interference: Effects on Calling in Oophaga pumilio

    PubMed Central

    Wong, Stefanie; Parada, Humberto; Narins, Peter M.

    2010-01-01

    Call rate suppression is a common short-term solution for avoiding acoustic interference in animals. It has been widely documented between and within frog species, but the effects of non-anuran calling on frog vocalizations is less well known. Heterospecific acoustic interference on the calling of Oophaga pumilio (Bauer, 1994) (formerly Dendrobates pumilio) males was studied in a lowland, wet tropical forest in SE Nicaragua. Acoustic playback experiments were conducted to characterize the responses of O. pumilio males to interfering calls of cicadas, two species of crickets and a sympatric dendrobatid frog, Phyllobates lugubris. Call rate, call bout duration, percent of time calling, dominant frequency and latency to first-call were analyzed. Significant call rate suppression was observed during all stimulus playbacks, yet no significant differences were found in spontaneous call rates during pre- and post-playback trials. Dominant frequency significantly decreased after P. lugubris playback and first-call latency significantly decreased in response to both cicada and tree cricket playbacks. These results provide robust evidence that O. pumilio males can dynamically modify their calling pattern in unique ways, depending on the source of the heterospecific acoustic interference. PMID:20953296

  14. Identification and characterization of the pumilio-2 expressed in zebrafish embryos and adult tissues.

    PubMed

    Wang, Huan Nan; Xu, Yan; Tao, Ling Jie; Zhou, Jian; Qiu, Meng Xi; Teng, Yu Hang; Deng, Feng Jiao

    2012-03-01

    Pumilio proteins regulate the translation of specific proteins required for germ cell development and morphogenesis. In the present study, we have identified the pumilio-2 in zebrafish and analyze its expression in adult tissues and early embryos. Pumilio-2 codes for the full-length Pumilio-2 protein and contains a PUF-domain. When compared to the mammalian and avian Pumilio-2 proteins, zebrafish Pumilio-2 protein was found to contain an additional sequence of 24 amino acid residues within the PUF-domain. Zebrafish pumilio-2 mRNA is expressed in the ovary, testis, liver, kidney and brain but is absent in the heart and muscle as detected by RT-PCR. The results of in situ hybridization indicate that transcripts of pumilio-2 are distributed in all blastomeres from the 1-cell stage to the sphere stage and accumulate in the head and tail during the 60%-epiboly and 3-somite stages. Transcripts were also detected in the brain and neural tube of the 24 h post-fertilization (hpf) embryos. Western blot analyses indicate that the Pumilio-2 protein is strongly expressed in the ovary, testis and brain but not in other tissues. These data suggest that pumilio-2 plays an important role in the development of the zebrafish germ cells and nervous system.

  15. The southernmost Andean Mountain soils: a toposequence from Nothofagus Forest to Sub Antarctic Tundra at Ushuaia, Tierra del Fuego

    NASA Astrophysics Data System (ADS)

    Firme Sá, Mariana M.; Schaefer, Carlos E.; Loureiro, Diego C.; Simas, Felipe N.; Francelino, Marcio R.; Senra, Eduardo O.

    2015-04-01

    Located at the southern tip of the Fuegian Andes Cordilhera, the Martial glacier witnessed a rapid process of retreat in the last century. Up to now little is known about the development and genesis of soils of this region. A toposequence of six soils, ranging from 430-925 m a.s.l, was investigated, with emphasis on genesis, chemical and mineralogical properties. The highest, youngest soil is located just below the Martial Glacier Martial Sur sector, and the lowest soils occur on sloping moraines under Nothofagus pumilio forests. Based on chemical, physical and mineralogical characteristics, the soils were classified according to the Soil taxonomy, being keyed out as Inceptisols and Entisols. Soil parent material of the soil is basically moraines, in which the predominant lithic components dominated by metamorphic rocks, with allochthonous contributions of wind-blown materials (very small fragments of volcanic glass) observed by hand lens in all horizons, except the highest profile under Tundra. In Nothofagus Deciduous Forests at the lowest part of the toposequence, poorly developed Inceptisols occur with Folistic horizons, with mixed "andic" and "spodic" characters, but with a predominance of andosolization (Andic Drystrocryepts). Under Tundra vegetation, Inceptisols are formed under hydromorphism and andosolization processes (Oxiaquic Dystrocrepts and Typic Dystrocrepts). On highland periglacial environments, soils without B horizon with strong evidence of cryoturbation and cryogenesis occur, without present-day permafrost down to 2 meters (Typic Cryorthents and Lithic Haploturbels). The mountain soils of Martial glacier generalize young, stony and rich in organic matter, with the exception of barely vegetated Tundra soils at higher altitudes. The forest soils are more acidic and have higher Al3+activity. All soils are dystrophic, except for the highest profile of the local periglacial environment. The organic carbon amounts are higher in forest soils and

  16. A Novel Function of Human Pumilio Proteins in Cytoplasmic Sensing of Viral Infection

    PubMed Central

    Narita, Ryo; Takahasi, Kiyohiro; Murakami, Etsu; Hirano, Emi; Yamamoto, Seiji P.; Yoneyama, Mitsutoshi; Kato, Hiroki; Fujita, Takashi

    2014-01-01

    RIG-I-like receptor (RLR) plays a pivotal role in the detection of invading pathogens to initiate type I interferon (IFN) gene transcription. Since aberrant IFN production is harmful, RLR signaling is strictly regulated. However, the regulatory mechanisms are not fully understood. By expression cloning, we identified Pumilio proteins, PUM1 and PUM2, as candidate positive regulators of RIG-I signaling. Overexpression of Pumilio proteins and their knockdown augmented and diminished IFN-β promoter activity induced by Newcastle disease virus (NDV), respectively. Both proteins showed a specific association with LGP2, but not with RIG-I or MDA5. Furthermore, all of these components were recruited to NDV-induced antiviral stress granules. Interestingly, biochemical analyses revealed that Pumilio increased double-stranded (ds) RNA binding affinity of LGP2; however, Pumilio was absent in the dsRNA-LGP2 complex, suggesting that Pumilio facilitates viral RNA recognition by LGP2 through its chaperon-like function. Collectively, our results demonstrate an unknown function of Pumilio in viral recognition by LGP2. PMID:25340845

  17. Pumilio facilitates miRNA regulation of the E2F3 oncogene

    PubMed Central

    Miles, Wayne O.; Tschöp, Katrin; Herr, Anabel; Ji, Jun-Yuan; Dyson, Nicholas J.

    2012-01-01

    E2F transcription factors are important regulators of cell proliferation and are frequently dysregulated in human malignancies. To identify novel regulators of E2F function, we used Drosophila as a model system to screen for mutations that modify phenotypes caused by reduced levels of dE2F1. This screen identified components of the Pumilio translational repressor complex (Pumilio, Nanos, and Brain tumor) as suppressors of dE2F1-RNAi phenotypes. Subsequent experiments provided evidence that Pumilio complexes repress dE2F1 levels and that this mechanism of post-transcriptional regulation is conserved in human cells. The human Pumilio homologs Pum 1 and Pum 2 repress the translation of E2F3 by binding to the E2F3 3′ untranslated region (UTR) and also enhance the activity of multiple E2F3 targeting microRNAs (miRNAs). E2F3 is an oncogene with strong proliferative potential and is regularly dysregulated or overexpressed in cancer. Interestingly, Pumilio/miRNA-mediated regulation of E2F3 is circumvented in cancer cells in several different ways. Bladder carcinomas selectively down-regulate miRNAs that cooperate with Pumilio to target E2F3, and multiple tumor cell lines shorten the 3′ end of the E2F3 mRNA, removing the Pumilio regulatory elements. These studies suggest that Pumilio–miRNA repression of E2F3 translation provides an important level of E2F regulation that is frequently abrogated in cancer cells. PMID:22345517

  18. Relaxed molecular clock provides evidence for long-distance dispersal of Nothofagus (southern beech).

    PubMed

    Knapp, Michael; Stöckler, Karen; Havell, David; Delsuc, Frédéric; Sebastiani, Federico; Lockhart, Peter J

    2005-01-01

    Nothofagus (southern beech), with an 80-million-year-old fossil record, has become iconic as a plant genus whose ancient Gondwanan relationships reach back into the Cretaceous era. Closely associated with Wegener's theory of "Kontinentaldrift", Nothofagus has been regarded as the "key genus in plant biogeography". This paradigm has the New Zealand species as passengers on a Moa's Ark that rafted away from other landmasses following the breakup of Gondwana. An alternative explanation for the current transoceanic distribution of species seems almost inconceivable given that Nothofagus seeds are generally thought to be poorly suited for dispersal across large distances or oceans. Here we test the Moa's Ark hypothesis using relaxed molecular clock methods in the analysis of a 7.2-kb fragment of the chloroplast genome. Our analyses provide the first unequivocal molecular clock evidence that, whilst some Nothofagus transoceanic distributions are consistent with vicariance, trans-Tasman Sea distributions can only be explained by long-distance dispersal. Thus, our analyses support the interpretation of an absence of Lophozonia and Fuscospora pollen types in the New Zealand Cretaceous fossil record as evidence for Tertiary dispersals of Nothofagus to New Zealand. Our findings contradict those from recent cladistic analyses of biogeographic data that have concluded transoceanic Nothofagus distributions can only be explained by vicariance events and subsequent extinction. They indicate that the biogeographic history of Nothofagus is more complex than envisaged under opposing polarised views expressed in the ongoing controversy over the relevance of dispersal and vicariance for explaining plant biodiversity. They provide motivation and justification for developing more complex hypotheses that seek to explain the origins of Southern Hemisphere biota. PMID:15660155

  19. Relaxed molecular clock provides evidence for long-distance dispersal of Nothofagus (southern beech).

    PubMed

    Knapp, Michael; Stöckler, Karen; Havell, David; Delsuc, Frédéric; Sebastiani, Federico; Lockhart, Peter J

    2005-01-01

    Nothofagus (southern beech), with an 80-million-year-old fossil record, has become iconic as a plant genus whose ancient Gondwanan relationships reach back into the Cretaceous era. Closely associated with Wegener's theory of "Kontinentaldrift", Nothofagus has been regarded as the "key genus in plant biogeography". This paradigm has the New Zealand species as passengers on a Moa's Ark that rafted away from other landmasses following the breakup of Gondwana. An alternative explanation for the current transoceanic distribution of species seems almost inconceivable given that Nothofagus seeds are generally thought to be poorly suited for dispersal across large distances or oceans. Here we test the Moa's Ark hypothesis using relaxed molecular clock methods in the analysis of a 7.2-kb fragment of the chloroplast genome. Our analyses provide the first unequivocal molecular clock evidence that, whilst some Nothofagus transoceanic distributions are consistent with vicariance, trans-Tasman Sea distributions can only be explained by long-distance dispersal. Thus, our analyses support the interpretation of an absence of Lophozonia and Fuscospora pollen types in the New Zealand Cretaceous fossil record as evidence for Tertiary dispersals of Nothofagus to New Zealand. Our findings contradict those from recent cladistic analyses of biogeographic data that have concluded transoceanic Nothofagus distributions can only be explained by vicariance events and subsequent extinction. They indicate that the biogeographic history of Nothofagus is more complex than envisaged under opposing polarised views expressed in the ongoing controversy over the relevance of dispersal and vicariance for explaining plant biodiversity. They provide motivation and justification for developing more complex hypotheses that seek to explain the origins of Southern Hemisphere biota.

  20. Optimization of an experimental model for the recovery of adult Haplorchis pumilio (Heterophyidae: Digenea).

    PubMed

    Kay, Helle; Murrell, K Darwin; Hansen, Axel Kornerup; Madsen, Henry; Trang, Nguyen Thi Thu; Hung, Nguyen Manh; Dalsgaard, Anders

    2009-06-01

    Recent studies in Vietnam and other Asian countries have shown that fish-borne zoonotic intestinal trematodes (FZT) occur very frequently in humans. The dominant intestinal FZT in Vietnamese fish are species of Haplorchis, in particular H. pumilio. However, basic studies on the biology and pathology of adult H. pumilio are difficult because of the lack of a standardized experimental animal model. The objective of this study was to establish and optimize such an animal-infection model for H. pumilio. Using metacercariae isolated from naturally infected fish, experiments were conducted to identify a suitable experimental animal host species, as well as the optimum metacercariae infection dose, and to determine the post-infection interval for patency. In a series of experiments, mice (Mus musculus) and chickens (Gallus gallus dom.) were infected with different numbers of metacercariae, and worm recoveries were made at varying intervals post-infection (PI). Based on the mean number of adult flukes recovered/number of metacercariae inoculated and the percent of hosts infected, mice were significantly more susceptible to infection than were chickens. The proportion of metacercariae developing to the adult stage increased with dose size. The peak worm recovery (geometric mean) was found to be day 7, although not all recovered flukes were gravid until day 9 PI. These results describe a mouse infection model with good predictability for intestinal flukes, such as H. pumilio, results which could facilitate investigations on important biological and pathological aspects of intestinal fluke infections.

  1. Structures of Human Pumilio with Noncognate RNAs Reveal Molecular Mechanisms for Binding Promiscuity

    SciTech Connect

    Gupta,Y.; Nair, D.; Wharton, R.; Aggarwal, A.

    2008-01-01

    Pumilio is a founder member of the evolutionarily conserved Puf family of RNA-binding proteins that control a number of physiological processes in eukaryotes. A structure of human Pumilio (hPum) Puf domain bound to a Drosophila regulatory sequence showed that each Puf repeat recognizes a single nucleotide. Puf domains in general bind promiscuously to a large set of degenerate sequences, but the structural basis for this promiscuity has been unclear. Here, we describe the structures of hPum Puf domain complexed to two noncognate RNAs, CycBreverse and Puf5. In each complex, one of the nucleotides is ejected from the binding surface, in effect, acting as a 'spacer.' The complexes also reveal the plasticity of several Puf repeats, which recognize noncanonical nucleotides. Together, these complexes provide a molecular basis for recognition of degenerate binding sites, which significantly increases the number of mRNAs targeted for regulation by Puf proteins in vivo.

  2. Gymnopanella nothofagi, a new genus and species of gymnopoid fungi (Omphalotaceae) from Chilean Nothofagus forest.

    PubMed

    Sandoval-Leiva, Pablo Andrés; McDonald, Jennifer V; Thorn, R Greg

    2016-01-01

    A novel, lignicolous agaric from Nothofagus forests of southern Chile is described as a new genus and species, Gymnopanella nothofagi This taxon falls within the family Omphalotaceae as a sister group to Gymnopus in phylogenetic analyses based on sequences spanning the internal transcribed spacer region and D1/D2 region of nuclear 28S rDNA. Morphologically it is characterized by convex to flabellate basidiomata with distinctly gelatinized trama, pileipellis in the form of a cutis with erect fascicles of cylindrical, spirally incrusted hyphae and nonamyloid, broadly ellipsoid basidiospores. This combination of features, in particular the lack of a rameales structure, serve to distinguish Gymnopanella from Gymnopus, Marasmiellus and other similar genera of the Omphalotaceae or Marasmiaceae. The new taxon is known only from Chilean Nothofagus forests at approximately 45-46° south latitude, but concerted searching in similar habitats in surrounding areas or in New Zealand may extend the known range considerably. PMID:27055572

  3. Experimental infection with the small intestinal trematode, Haplorchis pumilio, in young dogs.

    PubMed

    Nissen, Sofie; Nguyen, Lan Anh Thi; Dalsgaard, Anders; Thamsborg, Stig Milan; Johansen, Maria Vang

    2013-01-16

    Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on the role of domestic animals in the transmission of FZT in Northern Vietnam found that dogs, mainly infected with Haplorchis pumilio, contributed widely to the transmission of FZT. On this background, we conducted an experimental infection with H. pumilio to elucidate population dynamics and host reactions in dogs. Eight household-reared dogs (3-6 months old), were each orally infected with 500 H. pumilio metacercariae obtained by artificial digestion of naturally infected fish. Another eight dogs were included as uninfected controls. Faecal examination for eggs was performed twice weekly using a sieving and sedimentation technique. Body temperature and weight of the dogs were measured as was total white blood cells, blood eosinophils and packed cell volume. Subsets of dogs were examined post-mortem for presence of adult FZT at three different time points post infection by sectioning of the small intestine and caecum into four parts. Patent infections established in all eight infected dogs. The worm establishment ranged from 15 to 121 flukes (3-24%, mean 12%). Faecal egg excretion was measured in all eight infected dogs but no more than two eggs per g faeces (epg) were found at any time. Infections lasted for at least two months as documented by the presence of adult flukes in all three dogs necropsied on day 58 post infection. The predilection site of the flukes was identified as the lower part of jejunum (93% of total worm burden). The results of the haematological tests did not differ between the infected and uninfected group. Further, no clinical symptoms were observed in the infected group and no macroscopic pathological changes could be assigned to the trematode infections, neither did histopathological examination of the intestine reveal any differences between the infected and the control dogs. This study provides the first basic knowledge on the establishment

  4. Early Miocene Nothofagus in Antarctica based on fossil leaves from the Transantarctic Mountains

    NASA Astrophysics Data System (ADS)

    Wrobleski, S. A.; Ashworth, A. C.; Lewis, A. R.

    2014-12-01

    Nothofagus (Southern Beech) is the most widely reported plant from Cenozoic Antarctic fossil assemblages. Most of the fossils are of pollen morphotypes and it is assumed that the plants the pollen represents were growing on the continent. However, because of the uncertainties with systematics, long-distance dispersal, and reworking, it has been difficult to interpret the assemblages in terms of paleoenvironments and paleoclimate. Here, we report an in situ assemblage of Nothofagus leaves and pollen from the Friis Hills (77⁰ 45'S, 161⁰ 28'E). The leaves are preserved as carbonaceous impressions in brown, fissile shales that represent the deposits of a lake occupying a glacial valley. The leaves most probably accumulated from deciduous shrubs. Based on the stratigraphic relationship to a tephra with a 40 Ar/39 Ar age of c. 20 Ma, the leaf assemblage is of early Miocene age. Nothofagus pollen from the shale suggests that at least 3 species were represented. A total of 227 leaves were examined and lengths, widths, and areas recorded. The preservation is generally good but only a few of the specimens represent complete leaves; the spectrum is 30-100%. Plots of the measurements of the leaves provide a summary of size variation but were otherwise not useful for separating out different taxa . The most useful characters for establishing differences between the leaves were the leaf margins, of which three or four types were distinguished: 1. margins entire or finely serrate between ribs; 2. margins with one or two convex lobes between the ribs; 3. margins with convex lobes over the ribs. The leaf study indicates that three or possibly four species were co-inhabiting the valley in the early Miocene and were part of a dynamic vegetation that colonized the valley with each deglaciation. A possible analog today would be at low elevations in Tierra del Fuego where three species of Nothofagus coexist. The stem diameters of abundant wood preserved in adjacent facies indicates

  5. Intraspecific reproductive character displacement in a polymorphic poison dart frog, Dendrobates pumilio.

    PubMed

    Richards-Zawacki, Corinne L; Cummings, Molly E

    2011-01-01

    Divergence in male mating signals and associated female preferences is often an important step in the process of speciation. Reproductive character displacement, the pattern of greater divergence of male signals and/or female preference in sympatry than in allopatry, has been observed in a variety of taxa with different degrees of postzygotic isolation. A number of selective processes, including reinforcement, have been proposed to cause such a pattern. Cases in which reproductive character displacement occurs among intraspecific variants are especially informative for understanding how selection acting within a species can lead to the evolution of reproductive barriers and speciation. This study tested the hypothesis that female strawberry poison dart frogs (Dendrobates pumilio) in polymorphic populations of the Bocas del Toro archipelago of Panama show stronger mating discrimination than do females from monomorphic populations, exhibiting an intraspecific pattern of reproductive character displacement. Our results contribute important insights into understanding selection's role in generating the striking diversity of Bocas del Toro's D. pumilio and provide a snapshot of what could be the early stages of reproductive isolation and speciation. PMID:20825478

  6. Regulated Pumilio-2 binding controls RINGO/Spy mRNA translation and CPEB activation.

    PubMed

    Padmanabhan, Kiran; Richter, Joel D

    2006-01-15

    CPEB is a sequence-specific RNA-binding protein that controls the polyadenylation-induced translation of mos and cyclin B1 mRNAs in maturing Xenopus oocytes. CPEB activity requires not only the phosphorylation of S174, but also the synthesis of a heretofore-unknown upstream effector molecule. We show that the synthesis of RINGO/Spy, an atypical activator of cyclin-dependent kinases (cdks), is necessary for CPEB-directed polyadenylation. Deletion analysis and mRNA reporter assays show that a cis element in the RINGO/Spy 3'UTR is necessary for translational repression in immature (G2-arrested) oocytes. The repression is mediated by 3'UTR Pumilio-Binding Elements (PBEs), and by its binding protein Pumilio 2 (Pum2). Pum2 also interacts with the Xenopus homolog of human Deleted for Azoospermia-like (DAZL) and the embryonic poly(A)-binding protein (ePAB). Following the induction of maturation, Pum2 dissociates not only from RINGO/Spy mRNA, but from XDAZL and ePAB as well; as a consequence, RINGO/Spy mRNA is translated. These results demonstrate that a reversible Pum2 interaction controls RINGO/Spy mRNA translation and, as a result, CPEB-mediated cytoplasmic polyadenylation.

  7. Repression of Pumilio Protein Expression by Rbfox1 Promotes Germ Cell Differentiation.

    PubMed

    Carreira-Rosario, Arnaldo; Bhargava, Varsha; Hillebrand, Jens; Kollipara, Rahul K; Ramaswami, Mani; Buszczak, Michael

    2016-03-01

    RNA-binding Fox (Rbfox) proteins have well-established roles in regulating alternative splicing, but specific Rbfox isoforms lack nuclear localization signals and accumulate in the cytoplasm. The potential splicing-independent functions of these proteins remain unknown. Here we demonstrate that cytoplasmic Drosophila Rbfox1 regulates germ cell development and represses the translation of mRNAs containing (U)GCAUG elements within their 3'UTRs. During germline cyst differentiation, Rbfox1 targets pumilio mRNA for destabilization and translational silencing, thereby promoting germ cell development. Mis-expression of pumilio results in the formation of germline tumors, which contain cysts that break down and dedifferentiate back to single, mitotically active cells. Together, these results reveal that cytoplasmic Rbfox family members regulate the translation of specific target mRNAs. In the Drosophila ovary, this activity provides a genetic barrier that prevents germ cells from reverting back to an earlier developmental state. The finding that Rbfox proteins regulate mRNA translation has implications for Rbfox-related diseases. PMID:26954550

  8. Maternally derived chemical defences are an effective deterrent against some predators of poison frog tadpoles (Oophaga pumilio)

    PubMed Central

    Stynoski, Jennifer L.; Shelton, Georgia; Stynoski, Peter

    2014-01-01

    Parents defend their young in many ways, including provisioning chemical defences. Recent work in a poison frog system offers the first example of an animal that provisions its young with alkaloids after hatching or birth rather than before. But it is not yet known whether maternally derived alkaloids are an effective defence against offspring predators. We identified the predators of Oophaga pumilio tadpoles and conducted laboratory and field choice tests to determine whether predators are deterred by alkaloids in tadpoles. We found that snakes, spiders and beetle larvae are common predators of O. pumilio tadpoles. Snakes were not deterred by alkaloids in tadpoles. However, spiders were less likely to consume mother-fed O. pumilio tadpoles than either alkaloid-free tadpoles of the red-eyed treefrog, Agalychnis callidryas, or alkaloid-free O. pumilio tadpoles that had been hand-fed with A. callidryas eggs. Thus, maternally derived alkaloids reduce the risk of predation for tadpoles, but only against some predators. PMID:24850895

  9. A conserved abundant cytoplasmic long noncoding RNA modulates repression by Pumilio proteins in human cells

    PubMed Central

    Tichon, Ailone; Gil, Noa; Lubelsky, Yoav; Havkin Solomon, Tal; Lemze, Doron; Itzkovitz, Shalev; Stern-Ginossar, Noam; Ulitsky, Igor

    2016-01-01

    Thousands of long noncoding RNA (lncRNA) genes are encoded in the human genome, and hundreds of them are evolutionarily conserved, but their functions and modes of action remain largely obscure. Particularly enigmatic lncRNAs are those that are exported to the cytoplasm, including NORAD—an abundant and highly conserved cytoplasmic lncRNA. Here we show that most of the sequence of NORAD is comprised of repetitive units that together contain at least 17 functional binding sites for the two mammalian Pumilio homologues. Through binding to PUM1 and PUM2, NORAD modulates the mRNA levels of their targets, which are enriched for genes involved in chromosome segregation during cell division. Our results suggest that some cytoplasmic lncRNAs function by modulating the activities of RNA-binding proteins, an activity which positions them at key junctions of cellular signalling pathways. PMID:27406171

  10. Differences in prolactin levels between three alternative male reproductive tactics in striped mice (Rhabdomys pumilio)

    PubMed Central

    Schradin, Carsten

    2008-01-01

    In male fishes, birds and mammals, increased prolactin secretion is thought to play a role in species showing paternal behaviours. This hypothesis was investigated in the striped mouse (Rhabdomys pumilio). This paper compares serum prolactin levels in 71 free-living male striped mice following three different reproductive tactics: (i) paternal group-living breeders, (ii) alloparental philopatric group-living males, and (iii) roaming non-paternal solitary males. Prolactin levels of breeding males were significantly higher than that of roamers. Alloparental philopatric males had low prolactin levels, which concur with studies of cooperatively breeding mammals, but contrasts with studies of cooperatively breeding birds. Both breeding males and females showed a decrease in prolactin levels after the breeding season, but not alloparental philopatric males. Prolactin levels were correlated with neither corticosterone levels nor age. These results are in agreement with the hypothesis that prolactin is one proximate mechanism of male reproductive tactics, possibly regulating differences in male parental care. PMID:18230588

  11. Carotenoid supplementation enhances reproductive success in captive strawberry poison frogs (Oophaga pumilio).

    PubMed

    Dugas, Matthew B; Yeager, Justin; Richards-Zawacki, Corinne L

    2013-01-01

    Amphibians are currently experiencing the most severe declines in biodiversity of any vertebrate, and their requirements for successful reproduction are poorly understood. Here, we show that supplementing the diet of prey items (fruit flies) with carotenoids has strong positive effects on the reproduction of captive strawberry poison frogs (Oophaga pumilio), substantially increasing the number of metamorphs produced by pairs. This improved reproduction most likely arose via increases in the quality of both the fertilized eggs from which tadpoles develop and trophic eggs that are fed to tadpoles by mothers. Frogs in this colony had previously been diagnosed with a Vitamin A deficiency, and this supplementation may have resolved this issue. These results support growing evidence of the importance of carotenoids in vertebrate reproduction and highlight the nuanced ways in which nutrition constrains captive populations.

  12. Evidence of Pliocene Nothofagus in Antarctica from Pliocene marine sedimentary deposits (DSDP Site 274)

    USGS Publications Warehouse

    Fleming, R.F.; Barron, J.A.

    1996-01-01

    Microfossil assemblages in Pliocene sediments from DSDP Site 274 (68??59.81???S, 173??25.64???E) provide data on the age of the sediments and suggest the presence of Nothofagus (southern beech) in Antarctica during the Pliocene. A suite of 17 samples was collected in an interval from Samples 28-274-6R-1, 83-87 cm to 28-274-11R-4, 73-77 cm (48.33-100.29 mbsf). Biostratigraphic study of the abundant diatom assemblages combined with published radiolarian data indicates that the sample interval ranges in age from 5.0 to 2.2 Ma, with an apparent unconformity between about 3.8 and 3.2 Ma. Nothofagidites (the genus for fossil pollen referable to Nothofagus) occurs throughout the interval, as well as pollen and spores with known stratigraphic ranges that unequivocally indicate reworking from older rocks. Species of Nothofagidites recovered include N. asperus, N. brachyspinulosus, N. flemingii, N. senectus, and N. sp. cf. N. lachlaniae; the latter form is previously known from the Sirius Group in the Transantarctic Mountains. Abundant palynomorphs were recovered in only three of the samples from Site 274 (Samples 28-274-9R-2, 15-19 cm; 28-274-9R-2, 48-52 cm; and 28-274-9R-2, 65-69 cm). Based on the diatom and radiolarian biostratigraphic data, the ages of these samples range from 3.00 to 3.01 Ma. The relative abundance of N. sp. cf. N. lachlaniae in the three samples is an order of magnitude higher than relative abundances for the other species of Nothofagidites in the same samples. The significantly higher relative abundance of N. sp. cf. N. lachlaniae suggests that this pollen was derived from trees of Nothofagus that were living in Antarctica during the mid Pliocene. Diatom assemblages from these three samples indicate that sediments in this interval were rapidly deposited as biogenic oozes in an open-ocean setting relatively free of sea ice, thus decreasing the possibility of reworking from a single source bed rich in N. sp. cf. N. lachlaniae. Clearly, more detailed

  13. Seed dormancy responses to temperature relate to Nothofagus species distribution and determine temporal patterns of germination across altitudes in Patagonia.

    PubMed

    Arana, María V; Gonzalez-Polo, Marina; Martinez-Meier, Alejandro; Gallo, Leonardo A; Benech-Arnold, Roberto L; Sánchez, Rodolfo A; Batlla, Diego

    2016-01-01

    Seeds integrate environmental cues that modulate their dormancy and germination. Although many mechanisms have been identified in laboratory experiments, their contribution to germination dynamics in existing communities and their involvement in defining species habitats remain elusive. By coupling mathematical models with ecological data we investigated the contribution of seed temperature responses to the dynamics of germination of three Nothofagus species that are sharply distributed across different altitudes in the Patagonian Andes. Seed responsiveness to temperature of the three Nothofagus species was linked to the thermal characteristics of their preferred ecological niche. In their natural distribution range, there was overlap in the timing of germination of the species, which was restricted to mid-spring. By contrast, outside their species distribution range, germination was temporally uncoupled with altitude. This phenomenon was described mathematically by the interplay between interspecific differences in seed population thermal parameters and the range in soil thermic environments across different altitudes. The observed interspecific variations in seed responsiveness to temperature and its environmental regulation, constitute a major determinant of the dynamics of Nothofagus germination across elevations. This phenomenon likely contributes to the maintenance of patterns of species abundance across altitude by placing germinated seeds in a favorable environment for plant growth.

  14. Intestinal Helminths Recovered from Humans in Xieng Khouang Province, Lao PDR with a Particular Note on Haplorchis pumilio Infection

    PubMed Central

    Chai, Jong-Yil; Sohn, Woon-Mok; Jung, Bong-Kwang; Yong, Tai-Soon; Eom, Keeseon S.; Min, Duk-Young; Insisiengmay, Bounnaloth; Insisiengmay, Sithat; Phommasack, Bounlay; Rim, Han-Jong

    2015-01-01

    A survey of intestinal helminths was undertaken in riparian people in Xieng Khouang Province, Lao PDR. Fecal specimens were collected from 643 people (289 males and 354 females) residing in 4 districts (Nonghet, Kham, Phoukout, and Pek) and were examined by the Kato-Katz technique. The overall helminth egg positive rate was 41.2%, and hookworms revealed the highest prevalence (32.7%) followed by Trichuris trichiura (7.3%) and Ascaris lumbricoides (5.6%). The positive rate for small trematode eggs (STE), which may include Opisthorchis viverrini, heterophyids, and lecithodendriids, was 4.4%. For recovery of adult helminths, 12 STE or nematode/cestode egg-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 2 Haplorchis species (H. pumilio and H. taichui), Centrocestus formosanus, Opisthorchis viverrini, a species of cestode (Taenia saginata), and several species of nematodes including hookworms and Enterobius vermicularis were detected. The worm load for trematodes was the highest for H. pumilio with an average of 283.5 specimens per infected person followed by C. formosanus, H. taichui, and O. viverrini. The worm load for nematodes was the highest for hookworms (21.5/infected case) followed by E. vermicularis (3.2/infected case). The results revealed that the surveyed areas of Xieng Khouang Province, Lao PDR are endemic areas of various species of intestinal helminths. The STE found in the surveyed population were verified to be those of heterophyids, particularly H. pumilio. PMID:26323842

  15. Intestinal Helminths Recovered from Humans in Xieng Khouang Province, Lao PDR with a Particular Note on Haplorchis pumilio Infection.

    PubMed

    Chai, Jong-Yil; Sohn, Woon-Mok; Jung, Bong-Kwang; Yong, Tai-Soon; Eom, Keeseon S; Min, Duk-Young; Insisiengmay, Bounnaloth; Insisiengmay, Sithat; Phommasack, Bounlay; Rim, Han-Jong

    2015-08-01

    A survey of intestinal helminths was undertaken in riparian people in Xieng Khouang Province, Lao PDR. Fecal specimens were collected from 643 people (289 males and 354 females) residing in 4 districts (Nonghet, Kham, Phoukout, and Pek) and were examined by the Kato-Katz technique. The overall helminth egg positive rate was 41.2%, and hookworms revealed the highest prevalence (32.7%) followed by Trichuris trichiura (7.3%) and Ascaris lumbricoides (5.6%). The positive rate for small trematode eggs (STE), which may include Opisthorchis viverrini, heterophyids, and lecithodendriids, was 4.4%. For recovery of adult helminths, 12 STE or nematode/cestode egg-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 2 Haplorchis species (H. pumilio and H. taichui), Centrocestus formosanus, Opisthorchis viverrini, a species of cestode (Taenia saginata), and several species of nematodes including hookworms and Enterobius vermicularis were detected. The worm load for trematodes was the highest for H. pumilio with an average of 283.5 specimens per infected person followed by C. formosanus, H. taichui, and O. viverrini. The worm load for nematodes was the highest for hookworms (21.5/infected case) followed by E. vermicularis (3.2/infected case). The results revealed that the surveyed areas of Xieng Khouang Province, Lao PDR are endemic areas of various species of intestinal helminths. The STE found in the surveyed population were verified to be those of heterophyids, particularly H. pumilio.

  16. Intestinal Helminths Recovered from Humans in Xieng Khouang Province, Lao PDR with a Particular Note on Haplorchis pumilio Infection.

    PubMed

    Chai, Jong-Yil; Sohn, Woon-Mok; Jung, Bong-Kwang; Yong, Tai-Soon; Eom, Keeseon S; Min, Duk-Young; Insisiengmay, Bounnaloth; Insisiengmay, Sithat; Phommasack, Bounlay; Rim, Han-Jong

    2015-08-01

    A survey of intestinal helminths was undertaken in riparian people in Xieng Khouang Province, Lao PDR. Fecal specimens were collected from 643 people (289 males and 354 females) residing in 4 districts (Nonghet, Kham, Phoukout, and Pek) and were examined by the Kato-Katz technique. The overall helminth egg positive rate was 41.2%, and hookworms revealed the highest prevalence (32.7%) followed by Trichuris trichiura (7.3%) and Ascaris lumbricoides (5.6%). The positive rate for small trematode eggs (STE), which may include Opisthorchis viverrini, heterophyids, and lecithodendriids, was 4.4%. For recovery of adult helminths, 12 STE or nematode/cestode egg-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 2 Haplorchis species (H. pumilio and H. taichui), Centrocestus formosanus, Opisthorchis viverrini, a species of cestode (Taenia saginata), and several species of nematodes including hookworms and Enterobius vermicularis were detected. The worm load for trematodes was the highest for H. pumilio with an average of 283.5 specimens per infected person followed by C. formosanus, H. taichui, and O. viverrini. The worm load for nematodes was the highest for hookworms (21.5/infected case) followed by E. vermicularis (3.2/infected case). The results revealed that the surveyed areas of Xieng Khouang Province, Lao PDR are endemic areas of various species of intestinal helminths. The STE found in the surveyed population were verified to be those of heterophyids, particularly H. pumilio. PMID:26323842

  17. Karyotypic variation in Rhinophylla pumilio Peters, 1865 and comparative analysis with representatives of two subfamilies of Phyllostomidae (Chiroptera)

    PubMed Central

    Gomes, Anderson José Baia; Nagamachi, Cleusa Yoshiko; Rodrigues, Luís Reginaldo Ribeiro; Farias, Solange Gomes; Rissino, Jorge Dores; Pieczarka, Julio Cesar

    2012-01-01

    Abstract The family Phyllostomidae belongs to the most abundant and diverse group of bats in the Neotropics with more morphological traits variation at the family level than any other group within mammals. In this work, we present data of chromosome banding (G, C and Ag-NOR) and Fluorescence In Situ Hybridization (FISH) for representatives of Rhinophylla pumilio Peters, 1865 collected in four states of Brazil (Amazonas, Bahia, Mato Grosso and Pará). Two karyomorphs were found in this species: 2n=34, FN=64 in populations from western Pará and Mato Grosso states and 2n=34, FN=62 from Amazonas, Bahia, and northeastern Pará and Marajó Island (northern). Difference in the Fundamental Number is determined by variation in the size of the Nucleolar Organizer Region (NOR) accompanied with heterochromatin on chromosomes of pair 16 or, alternatively, a pericentric inversion. The C-banding technique detected constitutive heterochromatin in the centromeric regions of all chromosomes and on the distal part of the long arm of pair 15 of specimens from all localities. FISH with a DNA telomeric probe did not show any interstitial sequence, and an 18S rDNA probe and silver staining revealed the presence of NOR in the long arm of the pair 15, associated with heterochromatin, and in the short arm of the pair 16 for all specimens. The intra-specific analysis using chromosome banding did not show any significant difference between the samples. The comparative analyses using G-banding have shown that nearly all chromosomes of Rhinophylla pumilio were conserved in the chromosome complements of Glossophaga soricina Pallas, 1766, Phyllostomus hastatus Pallas, 1767, Phyllostomus discolor Wagner, 1843 and Mimon crenulatum Geoffroy, 1801, with a single chromosomal pair unique to Rhinophylla pumilio (pair 15). However, two chromosomes of Mimon crenulatum are polymorphic for two independent pericentric inversions. The karyotype with 2n=34, NF=62 is probably the ancestral one for the other

  18. Pumilio-2 regulates translation of Nav1.6 to mediate homeostasis of membrane excitability

    PubMed Central

    Driscoll, Heather E; Muraro, Nara I; He, Miaomiao; Baines, Richard A

    2013-01-01

    The ability to regulate intrinsic membrane excitability, in order to maintain consistency of action potential firing, is critical for stable neural circuit activity. Without such mechanisms, Hebbian-based synaptic plasticity could push circuits toward activity-saturation or, alternatively, quiescence. Although now well documented, the underlying molecular components of these homeostatic mechanisms remain poorly understood. Recent work in the fruit fly, Drosophila melanogaster, has identified Pumilio (Pum), a translational repressor, as an essential component of one such mechanism. In response to changing synaptic excitation, Pum regulates the translation of the voltage-gated sodium conductance leading to a concomitant adjustment in action potential firing. While similar homeostatic mechanisms are operational in mammalian neurons, it is unknown whether Pum is similarly involved. In this study, we report that Pum2 is indeed central to the homeostatic mechanism regulating membrane excitability in rat visual cortical pyramidal neurons. Using RNA interference, we observed that loss of Pum2 leads to increased sodium current (INa) and action potential firing, mimicking the response by these neurons to being deprived of synaptic depolarisation. By contrast, increased synaptic depolarisation results in increased Pum2 expression and subsequent reduction in INa and membrane excitability. We further show that Pum2 is able to directly bind the predominant voltage-gated sodium channel transcript (NaV1.6) expressed in these neurons and, through doing so, regulates translation of this key determinant of membrane excitability. Taken together, our results show that Pum2 forms part of a homeostatic mechanism that matches membrane excitability to synaptic depolarization in mammalian neurons. PMID:23739961

  19. A novel group of pumilio mutations affects the asymmetric division of germline stem cells in the Drosophila ovary.

    PubMed

    Lin, H; Spradling, A C

    1997-06-01

    Germline stem cells play a pivotal role in gametogenesis; yet little is known about how they are formed, how they divide to self-renew, and how these processes are genetically controlled. Here we describe the self-renewing asymmetric division of germline stem cells in the Drosophila ovarian germline, as marked by the spectrosome, a cytoplasmic structure rich in membrane skeletal proteins. The ontogeny of the spectrosome marks the lineage of germline stem cells. We identified two new groups of mutations in which the divisional asymmetry is disrupted. The first, which we refer to as ovarette (ovt) mutations, was shown to correspond to a novel class of mutations in the pumilio locus. Since pumilio is known to posttranscriptionally repress the expression of target genes at earlier stages of germ cell development, our results suggest that a similar activity is needed to maintain germ line stem cells. We have also identified a second and novel gene, piwi, whose mutations abolish germline stem cell division.

  20. Surface-bound phosphatase activity in living hyphae of ectomycorrhizal fungi of Nothofagus obliqua.

    PubMed

    Alvarez, Maricel; Godoy, Roberto; Heyser, Wolfgang; Härtel, Steffen

    2004-01-01

    We determined the location and the activity of surface-bound phosphomonoesterase (SBP) of five ectomycorrhizal (EM) fungi of Nothofagus oblique. EM fungal mycelium of Paxillus involutus, Austropaxillus boletinoides, Descolea antartica, Cenococcum geophilum and Pisolithus tinctorius was grown in media with varying concentrations of dissolved phosphorus. SBP activity was detected at different pH values (3-7) under each growth regimen. SBP activity was assessed using a colorimetric method based on the hydrolysis of p-nitrophenyl phosphate (pNPP) to p-nitrophenol phosphate (pNP) + P. A new technique involving confocal laser-scanning microscopy (LSM) was used to locate and quantify SBP activity on the hyphal surface. EM fungi showed two fundamentally different patterns of SBP activity in relation to varying environmental conditions (P-concentrations and pH). In the cases of D. antartica, A. boletinoides and C. geophilum, changes in SBP activity were induced primarily by changes in the number of SBP-active centers on the hyphae. In the cases of P. tinctorius and P. involutus, the number of SBP-active centers per μm hyphal length changed much less than the intensity of the SBP-active centers on the hyphae. Our findings not only contribute to the discussion about the role of SBP-active centers in EM fungi but also introduce LSM as a valuable method for studying EM fungi. PMID:21148871

  1. Effect of ectomycorrhizal colonization and drought on reactive oxygen species metabolism of Nothofagus dombeyi roots.

    PubMed

    Alvarez, Maricel; Huygens, Dries; Fernandez, Carlos; Gacitúa, Yessy; Olivares, Erick; Saavedra, Isabel; Alberdi, Miren; Valenzuela, Eduardo

    2009-08-01

    Infection with ectomycorrhizal fungi can increase the ability of plants to resist drought stress through morphophysiological and biochemical mechanisms. However, the metabolism of antioxidative enzyme activities in the ectomycorrhizal symbiosis remains poorly understood. This study investigated biomass production, reactive oxygen metabolism (hydrogen peroxide and malondialdehyde concentration) and antioxidant enzyme activity (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) in pure cultures of the ectomycorrhizal fungi Descolea antartica Sing. and Pisolithus tinctorius (Pers.) Coker & Couch, and non-mycorrhizal and mycorrhizal roots of Nothofagus dombeyi (Mirb.) roots under well-watered conditions and drought conditions (DC). The studied ectomycorrhizal fungi regulated their antioxidative enzyme metabolism differentially in response to drought, resulting in cellular damage in D. antartica but not in P. tinctorius. Ectomycorrhizal inoculation and water treatment had a significant effect on all parameters studied, including relative water content of the plant. As such, N. dombeyi plants in symbiosis experienced a lower oxidative stress effect than non-mycorrhizal plants under DC. Additionally, ectomycorrhizal N. dombeyi roots showed a greater antioxidant enzyme activity relative to non-mycorrhizal roots, an effect which was further expressed under DC. The association between the non-specific P. tinctorius and N. dombeyi had a more effective reactive oxygen species (ROS) metabolism than the specific D. antartica-N. dombeyi symbiosis. We conclude that the combination of effective ROS prevention and ROS detoxification by ectomycorrhizal plants resulted in reduced cellular damage and increased plant growth relative to non-mycorrhizal plants under drought. PMID:19483186

  2. Agrobacterium rhizogenes vs auxinic induction for in vitro rhizogenesis of Prosopis chilensis and Nothofagus alpina.

    PubMed

    Caro, Luis A; Santecchia, Natalia; Marinangeli, Pablo A; Curvetto, Néstor R; Hernández, Luis F

    2003-12-01

    The induction and improvement of in vitro rhizogenesis of microshoots of Prosopis chilensis (Mol.) Stuntz and Nothofagus alpina (Poep. et Endl. Oerst.) were compared using Agrobacterium rhizogenes (Ar) versus indole-3-butyric acid (IBA) in the culture media. Microshoots of P. chilensis (1-2 cm length), coming from in vitro grown seedlings, were cultivated in a modified Broadleaved Tree Medium (BTMm) containing half salt concentration of macronutrients and 0.05 mg x L(-1) benzilaminopurine (BAP). After 30 days, microshoots with 2-4 leaves were selected and cultured in BTMm-agar in presence or abscense of Ar and in combination with IBA. For N. alpina, the apical shoots with the first 2 true leaves, from 5 weeks old seedlings, were cultured in the abovementioned medium, but with 0.15 mg x L(-1) of BAP. After 2 months, microshoots with 2-3 leaves were selected and cultured in BTMm-agar, supplemented with 5 mg x L(-1) IBA or in liquid BTMm on perlite and, in the presence or absence of A. rhizogenes (Ar) and in combination with 3 mg x L(-1) IBA. Rooting in P. chilensis reached 100.0% when Ar infection was produced in the presence of IBA, increasing both, the number and dry weight of roots. In N. alpina, 90.0% of rooting efficiency was obtained when Ar infection was produced in liquid culture and in the absence of auxin. PMID:15002748

  3. Effect of ectomycorrhizal colonization and drought on reactive oxygen species metabolism of Nothofagus dombeyi roots.

    PubMed

    Alvarez, Maricel; Huygens, Dries; Fernandez, Carlos; Gacitúa, Yessy; Olivares, Erick; Saavedra, Isabel; Alberdi, Miren; Valenzuela, Eduardo

    2009-08-01

    Infection with ectomycorrhizal fungi can increase the ability of plants to resist drought stress through morphophysiological and biochemical mechanisms. However, the metabolism of antioxidative enzyme activities in the ectomycorrhizal symbiosis remains poorly understood. This study investigated biomass production, reactive oxygen metabolism (hydrogen peroxide and malondialdehyde concentration) and antioxidant enzyme activity (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) in pure cultures of the ectomycorrhizal fungi Descolea antartica Sing. and Pisolithus tinctorius (Pers.) Coker & Couch, and non-mycorrhizal and mycorrhizal roots of Nothofagus dombeyi (Mirb.) roots under well-watered conditions and drought conditions (DC). The studied ectomycorrhizal fungi regulated their antioxidative enzyme metabolism differentially in response to drought, resulting in cellular damage in D. antartica but not in P. tinctorius. Ectomycorrhizal inoculation and water treatment had a significant effect on all parameters studied, including relative water content of the plant. As such, N. dombeyi plants in symbiosis experienced a lower oxidative stress effect than non-mycorrhizal plants under DC. Additionally, ectomycorrhizal N. dombeyi roots showed a greater antioxidant enzyme activity relative to non-mycorrhizal roots, an effect which was further expressed under DC. The association between the non-specific P. tinctorius and N. dombeyi had a more effective reactive oxygen species (ROS) metabolism than the specific D. antartica-N. dombeyi symbiosis. We conclude that the combination of effective ROS prevention and ROS detoxification by ectomycorrhizal plants resulted in reduced cellular damage and increased plant growth relative to non-mycorrhizal plants under drought.

  4. Surface-bound phosphatase activity in living hyphae of ectomycorrhizal fungi of Nothofagus obliqua.

    PubMed

    Alvarez, Maricel; Godoy, Roberto; Heyser, Wolfgang; Härtel, Steffen

    2004-01-01

    We determined the location and the activity of surface-bound phosphomonoesterase (SBP) of five ectomycorrhizal (EM) fungi of Nothofagus oblique. EM fungal mycelium of Paxillus involutus, Austropaxillus boletinoides, Descolea antartica, Cenococcum geophilum and Pisolithus tinctorius was grown in media with varying concentrations of dissolved phosphorus. SBP activity was detected at different pH values (3-7) under each growth regimen. SBP activity was assessed using a colorimetric method based on the hydrolysis of p-nitrophenyl phosphate (pNPP) to p-nitrophenol phosphate (pNP) + P. A new technique involving confocal laser-scanning microscopy (LSM) was used to locate and quantify SBP activity on the hyphal surface. EM fungi showed two fundamentally different patterns of SBP activity in relation to varying environmental conditions (P-concentrations and pH). In the cases of D. antartica, A. boletinoides and C. geophilum, changes in SBP activity were induced primarily by changes in the number of SBP-active centers on the hyphae. In the cases of P. tinctorius and P. involutus, the number of SBP-active centers per μm hyphal length changed much less than the intensity of the SBP-active centers on the hyphae. Our findings not only contribute to the discussion about the role of SBP-active centers in EM fungi but also introduce LSM as a valuable method for studying EM fungi.

  5. Gender differences in the inhibitory effects of a reduction in ambient temperature and a reduction in food quantity on reproduction in the Southern African rodent, Rhabdomys pumilio.

    PubMed

    Jackson, C; Bernard, R T

    2001-09-01

    The effects of a reduction in ambient temperature (from 26 degrees C to 15 degrees C) and a 10% reduction in daily food consumption on reproductively active male and female four-striped field mice ( Rhabdomys pumilio) were investigated. In male R. pumilio, both reduced ambient temperature and a reduction in food quantity had an inhibitory effect on spermatogenesis and on size of the reproductive organs, and this was greatest when the two factors were combined and the effect of fat was removed. Female R. pumilio responded differently and reproduction was inhibited by a reduction in food quantity, irrespective of ambient temperature. The masses of the ovaries and uterus, the numbers of developing follicles and corpora lutea, and the development of the uterine wall were all reduced by food deprivation at 26 degrees C to levels similar to those that resulted from a reduction in ambient temperature to 15 degrees C with a reduction in food quantity. It is concluded that reproduction in R. pumilio from the Eastern Cape Province of South Africa is opportunistic, that reproduction will be inhibited by an energetic challenge and that there is sexual dimorphism in the response to ambient temperature and food supply.

  6. Chemical and Antioxidant Properties of Wild Edible Mushrooms from Native Nothofagus spp. Forest, Argentina.

    PubMed

    Toledo, Carolina V; Barroetaveña, Carolina; Fernandes, Ângela; Barros, Lillian; Ferreira, Isabel C F R

    2016-01-01

    This study addresses issues regarding chemical and bioactive properties of nine wild edible mushrooms from native Nothofagus forest from Patagonia, Argentina. Macronutrients, sugars, fatty acids, tocopherols, organic acids, phenolic compounds and antioxidant properties were determined. Protein was found in high levels and varied between 3.35 g/100 g dw in Cyttaria hariotii and 22.29 g/100 g dw in Lepista nuda. All of them presented mannitol and trehalose as main sugars. Mannitol was significantly higher in Ramaria patagonica, although absent in Fistulina endoxantha, whereas trehalose predominated in Aleurodiscus vitellinus, Hydropus dusenii, Cortinarius magellanicus, C. hariotii, Grifola gargal and L. nuda, ranging from 1.15 to 10.26 g/100 g dw; it was absent in R. patagonica. The major fatty acid found was linoleic acid, followed by oleic acid and palmitic acid. All species presented oxalic and fumaric acids, while some also had malic, quinic and citric acids. Tocopherols composition was variable. Cortinarius magellanicus presented significantly higher contents of both α-tocopherol and β-tocopherol. R. patagonica presented the best results in all the antioxidant activity assays (EC50 values ≤ 1 mg/mL) and the highest content of phenolic compounds presenting gallic, p-hydroxybenzoic, p-coumaric and cinnamic acids. This study constitutes the first report on chemical composition and nutritional value of most of these edible mushroom species. Furthermore, it provides important information necessary to characterize and define the use of these species as gastronomic delicacies, functional foods and sources of bioactive compounds. PMID:27617993

  7. Solar radiation transmission in and around canopy gaps in an uneven-aged Nothofagus betuloides forest.

    PubMed

    Promis, Alvaro; Schindler, Dirk; Reif, Albert; Cruz, Gustavo

    2009-07-01

    The transmission of direct, diffuse and global solar radiation in and around canopy gaps occurring in an uneven-aged, evergreen Nothofagus betuloides forest during the growing season (October 2006-March 2007) was estimated by means of hemispherical photographs. The transmission of solar radiation into the forest was affected not only by a high level of horizontal and vertical heterogeneity of the forest canopy, but also by low angles of the sun's path. The below-canopy direct solar radiation appeared to be variable in space and time. On average, the highest amount of transmitted direct solar radiation was estimated below the undisturbed canopy at the southeast of the gap centre. The transmitted diffuse and global solar radiation above the forest floor exhibited lower variability and, on average, both were higher at the centre of the canopy gaps. Canopy structure and stand parameters were also measured to explain the variation in the below-canopy solar radiation in the forest. The model that best fit the transmitted below-canopy direct solar radiation was a growth model, using plant area index with an ellipsoidal angle distribution as the independent variable (R (2) = 0.263). Both diffuse and global solar radiation were very sensitive to canopy openness, and for both cases a quadratic model provided the best fit for these data (R (2) = 0.963 and 0.833, respectively). As much as 75% and 73% of the variation in the diffuse and global solar radiation, respectively, were explained by a combination of stand parameters, namely basal area, crown projection, crown volume, stem volume, and average equivalent crown radius.

  8. Size-specific tree mortality varies with neighbourhood crowding and disturbance in a Montane Nothofagus forest.

    PubMed

    Hurst, Jennifer M; Allen, Robert B; Coomes, David A; Duncan, Richard P

    2011-01-01

    Tree mortality is a fundamental process governing forest dynamics, but understanding tree mortality patterns is challenging because large, long-term datasets are required. Describing size-specific mortality patterns can be especially difficult, due to few trees in larger size classes. We used permanent plot data from Nothofagus solandri var. cliffortioides (mountain beech) forest on the eastern slopes of the Southern Alps, New Zealand, where the fates of trees on 250 plots of 0.04 ha were followed, to examine: (1) patterns of size-specific mortality over three consecutive periods spanning 30 years, each characterised by different disturbance, and (2) the strength and direction of neighbourhood crowding effects on size-specific mortality rates. We found that the size-specific mortality function was U-shaped over the 30-year period as well as within two shorter periods characterised by small-scale pinhole beetle and windthrow disturbance. During a third period, characterised by earthquake disturbance, tree mortality was less size dependent. Small trees (<20 cm in diameter) were more likely to die, in all three periods, if surrounded by a high basal area of larger neighbours, suggesting that size-asymmetric competition for light was a major cause of mortality. In contrast, large trees (≥ 20 cm in diameter) were more likely to die in the first period if they had few neighbours, indicating that positive crowding effects were sometimes important for survival of large trees. Overall our results suggest that temporal variability in size-specific mortality patterns, and positive interactions between large trees, may sometimes need to be incorporated into models of forest dynamics.

  9. Short day length alone does not inhibit spermatogenesis in the seasonally breeding four-striped field mouse (Rhabdomys pumilio).

    PubMed

    Jackson, C; Bernard, R T

    1999-06-01

    This study was an examination of the effect of photoperiod on spermatogenesis and the accessory glands of the four-striped field mouse (Rhabdomys pumilio), a seasonally breeding rodent that occurs through Southern Africa. Adult scrotal males were exposed to either short day length (10L:14D), long day length (14L:10D), or natural photoperiod in constant-environment rooms (25 degrees C, 41% humidity; food and water ad libitum) for 8 wk in late summer, when males in the wild were spermatogenically active, and in mid-winter, when they were inactive. In neither experiment did prolonged exposure to short day length or naturally decreasing day length inhibit spermatogenic activity, and we conclude that the normal cessation of spermatogenesis that occurs in most male four-striped field mice in winter is not stimulated by day length alone.

  10. PUMILIO-2 is involved in the positive regulation of cellular proliferation in human adipose-derived stem cells.

    PubMed

    Shigunov, Patrícia; Sotelo-Silveira, Jose; Kuligovski, Crisciele; de Aguiar, Alessandra Melo; Rebelatto, Carmen K; Moutinho, José A; Brofman, Paulo S; Krieger, Marco A; Goldenberg, Samuel; Munroe, David; Correa, Alejandro; Dallagiovanna, Bruno

    2012-01-20

    Stem cells can either differentiate into more specialized cells or undergo self-renewal. Several lines of evidence from different organisms suggest that these processes depend on the post-transcriptional regulation of gene expression. The presence of the PUF [Pumilio/FBF (fem-3 binding factor)] domain defines a conserved family of RNA binding proteins involved in repressing gene expression. It has been suggested that a conserved function of PUF proteins is to repress differentiation and sustain the mitotic proliferation of stem cells. In humans, Pumilio-2 (PUM2) is expressed in embryonic stem cells and adult germ cells. Here we show that PUM2 is expressed in a subpopulation of adipose-derived stem cell (ASC) cultures, with a granular pattern of staining in the cytoplasm. Protein levels of PUM2 showed no changes during the differentiation of ASCs into adipocytes. Moreover, RNAi knockdown of pum2 did not alter the rate of adipogenic differentiation compared with wild-type control cells. A ribonomic approach was used to identify PUM2-associated mRNAs. Microarray analysis showed that PUM2-bound mRNAs are part of gene networks involved in cell proliferation and gene expression control. We studied pum2 expression in cell cultures with low or very high levels of proliferation and found that changes in pum2 production were dependent on the proliferation status of the cell. Transient knockdown of pum2 expression by RNAi impaired proliferation of ASCs in vitro. Our results suggest that PUM2 does not repress differentiation of ASCs but rather is involved in the positive control of ASCs division and proliferation.

  11. PUMILIO-2 Is Involved in the Positive Regulation of Cellular Proliferation in Human Adipose-Derived Stem Cells

    PubMed Central

    Shigunov, Patrícia; Kuligovski, Crisciele; de Aguiar, Alessandra Melo; Rebelatto, Carmen K.; Moutinho, José A.; Brofman, Paulo S.; Krieger, Marco A.; Goldenberg, Samuel; Munroe, David; Correa, Alejandro

    2012-01-01

    Stem cells can either differentiate into more specialized cells or undergo self-renewal. Several lines of evidence from different organisms suggest that these processes depend on the post-transcriptional regulation of gene expression. The presence of the PUF [Pumilio/FBF (fem-3 binding factor)] domain defines a conserved family of RNA binding proteins involved in repressing gene expression. It has been suggested that a conserved function of PUF proteins is to repress differentiation and sustain the mitotic proliferation of stem cells. In humans, Pumilio-2 (PUM2) is expressed in embryonic stem cells and adult germ cells. Here we show that PUM2 is expressed in a subpopulation of adipose-derived stem cell (ASC) cultures, with a granular pattern of staining in the cytoplasm. Protein levels of PUM2 showed no changes during the differentiation of ASCs into adipocytes. Moreover, RNAi knockdown of pum2 did not alter the rate of adipogenic differentiation compared with wild-type control cells. A ribonomic approach was used to identify PUM2-associated mRNAs. Microarray analysis showed that PUM2-bound mRNAs are part of gene networks involved in cell proliferation and gene expression control. We studied pum2 expression in cell cultures with low or very high levels of proliferation and found that changes in pum2 production were dependent on the proliferation status of the cell. Transient knockdown of pum2 expression by RNAi impaired proliferation of ASCs in vitro. Our results suggest that PUM2 does not repress differentiation of ASCs but rather is involved in the positive control of ASCs division and proliferation. PMID:21649561

  12. Effects of supplementary food on the winter inhibition of reproduction in male and female four-striped field mice (Rhabdomys pumilio).

    PubMed

    Jackson, C; Bernard, R T F

    2005-01-01

    The effects of winter food supplementation on reproduction in the seasonally breeding four-striped field mouse Rhabdomys pumilio were investigated at Mountain Zebra National Park in the Eastern Cape Province of South Africa. On both control and supplemented grids, reproductive activity in females was inhibited; no pregnant females were collected and juveniles were only present in the first winter month. The provision of additional food resulted in an increase in body mass and mass of the male and female reproductive organs. However, all males, from both grids, were spermatogenically active. Ovarian activity was not stimulated by the provision of additional food, but the development of the uterus was and the endometrium was thicker and more vascularised in mice from the supplemented grid than from the control grid. We conclude that seasonal reproduction in R. pumilio is controlled by the females, in which reproductive activity is inhibited in winter. However, the provision of supplementary food was not sufficient to override the reproductive inhibition.

  13. Sexual selection can increase the effect of random genetic drift--a quantitative genetic model of polymorphism in Oophaga pumilio, the strawberry poison-dart frog.

    PubMed

    Tazzyman, Samuel J; Iwasa, Yoh

    2010-06-01

    The variation in color pattern between populations of the poison-dart frog Oophaga pumilio across the Bocas del Toro archipelago in Panama is suggested to be due to sexual selection, as two other nonsexually selecting Dendrobatid species found in the same habitat and range do not exhibit this variation. We theoretically test this assertion using a quantitative genetic sexual selection model incorporating aposematic coloration and random drift. We find that sexual selection could cause the observed variation via a novel process we call "coupled drift." Within our model, for certain parameter values, sexual selection forces frog color to closely follow the evolution of female preference. Any between-population variation in preference due to genetic drift is passed on to color. If female preference in O. pumilio is strongly affected by drift, whereas color in the nonsexually selecting Dendrobatid species is not, coupled drift will cause increased between-population phenotypic variation. However, with different parameter values, coupled drift will result in between-population variation in color being suppressed compared to its neutral value, or in little or no effect. We suggest that coupled drift is a novel theoretical process that could have a role linking sexual selection with speciation both in O. pumilio, and perhaps more generally. PMID:20015236

  14. Sexual selection can increase the effect of random genetic drift--a quantitative genetic model of polymorphism in Oophaga pumilio, the strawberry poison-dart frog.

    PubMed

    Tazzyman, Samuel J; Iwasa, Yoh

    2010-06-01

    The variation in color pattern between populations of the poison-dart frog Oophaga pumilio across the Bocas del Toro archipelago in Panama is suggested to be due to sexual selection, as two other nonsexually selecting Dendrobatid species found in the same habitat and range do not exhibit this variation. We theoretically test this assertion using a quantitative genetic sexual selection model incorporating aposematic coloration and random drift. We find that sexual selection could cause the observed variation via a novel process we call "coupled drift." Within our model, for certain parameter values, sexual selection forces frog color to closely follow the evolution of female preference. Any between-population variation in preference due to genetic drift is passed on to color. If female preference in O. pumilio is strongly affected by drift, whereas color in the nonsexually selecting Dendrobatid species is not, coupled drift will cause increased between-population phenotypic variation. However, with different parameter values, coupled drift will result in between-population variation in color being suppressed compared to its neutral value, or in little or no effect. We suggest that coupled drift is a novel theoretical process that could have a role linking sexual selection with speciation both in O. pumilio, and perhaps more generally.

  15. Testing the impact of calibration on molecular divergence times using a fossil-rich group: the case of Nothofagus (Fagales).

    PubMed

    Sauquet, Hervé; Ho, Simon Y W; Gandolfo, Maria A; Jordan, Gregory J; Wilf, Peter; Cantrill, David J; Bayly, Michael J; Bromham, Lindell; Brown, Gillian K; Carpenter, Raymond J; Lee, Daphne M; Murphy, Daniel J; Sniderman, J M Kale; Udovicic, Frank

    2012-03-01

    Although temporal calibration is widely recognized as critical for obtaining accurate divergence-time estimates using molecular dating methods, few studies have evaluated the variation resulting from different calibration strategies. Depending on the information available, researchers have often used primary calibrations from the fossil record or secondary calibrations from previous molecular dating studies. In analyses of flowering plants, primary calibration data can be obtained from macro- and mesofossils (e.g., leaves, flowers, and fruits) or microfossils (e.g., pollen). Fossil data can vary substantially in accuracy and precision, presenting a difficult choice when selecting appropriate calibrations. Here, we test the impact of eight plausible calibration scenarios for Nothofagus (Nothofagaceae, Fagales), a plant genus with a particularly rich and well-studied fossil record. To do so, we reviewed the phylogenetic placement and geochronology of 38 fossil taxa of Nothofagus and other Fagales, and we identified minimum age constraints for up to 18 nodes of the phylogeny of Fagales. Molecular dating analyses were conducted for each scenario using maximum likelihood (RAxML + r8s) and Bayesian (BEAST) approaches on sequence data from six regions of the chloroplast and nuclear genomes. Using either ingroup or outgroup constraints, or both, led to similar age estimates, except near strongly influential calibration nodes. Using "early but risky" fossil constraints in addition to "safe but late" constraints, or using assumptions of vicariance instead of fossil constraints, led to older age estimates. In contrast, using secondary calibration points yielded drastically younger age estimates. This empirical study highlights the critical influence of calibration on molecular dating analyses. Even in a best-case situation, with many thoroughly vetted fossils available, substantial uncertainties can remain in the estimates of divergence times. For example, our estimates for

  16. Preformation and distribution of staminate and pistillate flowers in growth units of Nothofagus alpina and N. obliqua (Nothofagaceae)

    PubMed Central

    Puntieri, Javier G.; Grosfeld, Javier E.; Heuret, Patrick

    2009-01-01

    Background and Aims The distribution and differentiation times of flowers in monoecious wind-pollinated plants are fundamental for the understanding of their mating patterns and evolution. Two closely related South American Nothofagus species were compared with regard to the differentiation times and positions of staminate and pistillate flowers along their parent growth units (GUs) by quantitative means. Methods Two samples of GUs that had extended in the 2004–2005 growing season were taken in 2005 and 2006 from trees in the Lanín National Park, Patagonia, Argentina. For the first sample, axillary buds of the parent GUs were dissected and the leaf, bud and flower primordia of these buds were identified. The second sample included all branches derived from the parent GUs in the 2005–2006 growing season. Key Results Both species developed flowering GUs with staminate and/or pistillate flowers; GUs with both flower types were the most common. The position of staminate flowers along GUs was similar between species and close to the proximal end of the GUs. Pistillate flowers were developed more distally along the GUs in N. alpina than in N. obliqua. In N. alpina, the nodes bearing staminate and pistillate flowers were separated by one to several nodes with axillary buds, something not observed in N. obliqua. Markovian models supported this between-species difference. Flowering GUs, including all of their leaves and flowers were entirely preformed in the winter buds. Conclusions Staminate and pistillate flowers of N. alpina and N. obliqua are differentiated at precise locations on GUs in the growing season preceding that of their antheses. The differences between N. alpina and N. obliqua (and other South American Nothofagus species) regarding flower distribution might relate to the time of anthesis of each flower type and, in turn, to the probabilities of self-pollination at the GU level. PMID:19033286

  17. Hydraulic differences along the water transport system of South American Nothofagus species: do leaves protect the stem functionality?

    PubMed

    Bucci, Sandra J; Scholz, Fabian G; Campanello, Paula I; Montti, Lia; Jimenez-Castillo, Mylthon; Rockwell, Fulton A; Manna, Ludmila La; Guerra, Pedro; Bernal, Pablo Lopez; Troncoso, Oscar; Enricci, Juan; Holbrook, Michele N; Goldstein, Guillermo

    2012-07-01

    Hydraulic traits were studied for six Nothofagus species from South America (Argentina and Chile), and for three of these species two populations were studied. The main goal was to determine if properties of the water conductive pathway in stems and leaves are functionally coordinated and to assess if leaves are more vulnerable to cavitation than stems, consistent with the theory of hydraulic segmentation along the vascular system of trees in ecosystems subject to seasonal drought. Vulnerability to cavitation, hydraulic conductivity of stems and leaves, leaf water potential, wood density and leaf water relations were examined. Large variations in vulnerability to cavitation of stems and leaves were observed across populations and species, but leaves were consistently more vulnerable than stems. Water potential at 50% loss of maximum hydraulic efficiency (P(50)) ranged from -0.94 to -2.44 MPa in leaves and from -2.6 to -5.3 MPa in stems across species and populations. Populations in the driest sites had sapwood and leaves more vulnerable to cavitation than those grown in the wettest sites. Stronger diurnal down-regulation in leaf hydraulic conductance compared with stem hydraulic conductivity apparently has the function to slow down potential water loss in stems and protect stem hydraulics from cavitation. Species-specific differences in wood density and leaf hydraulic conductance (K(Leaf)) were observed. Both traits were functionally related: species with higher wood density had lower K(Leaf). Other stem and leaf hydraulic traits were functionally coordinated, resulting in Nothofagus species with an efficient delivery of water to the leaves. The integrity of the more expensive woody portion of the water transport pathway can thus be maintained at the expense of the replaceable portion (leaves) of the stem-leaf continuum under prolonged drought. Compensatory adjustments between hydraulic traits may help to decrease the rate of embolism formation in the trees more

  18. The LSD1 Family of Histone Demethylases and the Pumilio Posttranscriptional Repressor Function in a Complex Regulatory Feedback Loop

    PubMed Central

    Miles, Wayne O.; Lepesant, Julie M. J.; Bourdeaux, Jessie; Texier, Manuela; Kerenyi, Marc A.; Nakakido, Makoto; Hamamoto, Ryuji; Orkin, Stuart H.; Dyson, Nicholas J.

    2015-01-01

    The lysine (K)-specific demethylase (LSD1) family of histone demethylases regulates chromatin structure and the transcriptional potential of genes. LSD1 is frequently deregulated in tumors, and depletion of LSD1 family members causes developmental defects. Here, we report that reductions in the expression of the Pumilio (PUM) translational repressor complex enhanced phenotypes due to dLsd1 depletion in Drosophila. We show that the PUM complex is a target of LSD1 regulation in fly and mammalian cells and that its expression is inversely correlated with LSD1 levels in human bladder carcinoma. Unexpectedly, we find that PUM posttranscriptionally regulates LSD1 family protein levels in flies and human cells, indicating the existence of feedback loops between the LSD1 family and the PUM complex. Our results highlight a new posttranscriptional mechanism regulating LSD1 activity and suggest that the feedback loop between the LSD1 family and the PUM complex may be functionally important during development and in human malignancies. PMID:26438601

  19. Drosophila Nanos acts as a molecular clamp that modulates the RNA-binding and repression activities of Pumilio

    PubMed Central

    Weidmann, Chase A; Qiu, Chen; Arvola, René M; Lou, Tzu-Fang; Killingsworth, Jordan; Campbell, Zachary T; Tanaka Hall, Traci M; Goldstrohm, Aaron C

    2016-01-01

    Collaboration among the multitude of RNA-binding proteins (RBPs) is ubiquitous, yet our understanding of these key regulatory complexes has been limited to single RBPs. We investigated combinatorial translational regulation by Drosophila Pumilio (Pum) and Nanos (Nos), which control development, fertility, and neuronal functions. Our results show how the specificity of one RBP (Pum) is modulated by cooperative RNA recognition with a second RBP (Nos) to synergistically repress mRNAs. Crystal structures of Nos-Pum-RNA complexes reveal that Nos embraces Pum and RNA, contributes sequence-specific contacts, and increases Pum RNA-binding affinity. Nos shifts the recognition sequence and promotes repression complex formation on mRNAs that are not stably bound by Pum alone, explaining the preponderance of sub-optimal Pum sites regulated in vivo. Our results illuminate the molecular mechanism of a regulatory switch controlling crucial gene expression programs, and provide a framework for understanding how the partnering of RBPs evokes changes in binding specificity that underlie regulatory network dynamics. DOI: http://dx.doi.org/10.7554/eLife.17096.001 PMID:27482653

  20. The Drosophila pumilio gene encodes two functional protein isoforms that play multiple roles in germline development, gonadogenesis, oogenesis and embryogenesis.

    PubMed Central

    Parisi, M; Lin, H

    1999-01-01

    The pumilio (pum) gene plays an essential role in embryonic patterning and germline stem cell (GSC) maintenance during oogenesis in Drosophila. Here we report on a phenotypic analysis using pum(ovarette) mutations, which reveals multiple functions of pum in primordial germ cell proliferation, larval ovary formation, GSC division, and subsequent oogenic processes, as well as in oviposition. Specifically, by inducing pum(-) GSC clones at the onset of oogenesis, we show that pum is directly involved in GSC division, a function that is distinct from its requirement in primordial germ cells. Furthermore, we show that pum encodes 156- and 130-kD proteins, both of which are functional isoforms. Among pum(ovarette) mutations, pum(1688) specifically eliminates the 156-kD isoform but not the 130-kD isoform, while pum(2003) and pum(4277) specifically affect the 130-kD isoform but not the 156-kD isoform. Normal doses of both isoforms are required for the zygotic function of pum, yet either isoform alone at a normal dose is sufficient for the maternal effect function of pum. A pum cDNA transgene that contains the known open reading frame encodes only the 156-kD isoform and rescues the phenotype of both pum(1688) and pum(2003) mutants. These observations suggest that the 156- and 130-kD isoforms can compensate for each other's function in a dosage-dependent manner. Finally, we present molecular evidence suggesting that the two PUM isoforms share some of their primary structures. PMID:10471709

  1. Genetic Diversity in Nothofagus alessandrii (Fagaceae), an Endangered Endemic Tree Species of the Coastal Maulino Forest of Central Chile

    PubMed Central

    Torres-Díaz, Cristian; Ruiz, Eduardo; González, Fidelina; Fuentes, Glenda; Cavieres, Lohengrin A.

    2007-01-01

    Background and Aims The endemic tree Nothofagus alessandrii (Fagaceae) has been historically restricted to the coastal range of Region VII of central Chile, and its forests have been increasingly destroyed and fragmented since the end of the 19th century. In this study, the patterns of within- and among-population genetic diversity in seven fragments of this endangered narrowly endemic tree were examined. Methods Allozyme electrophoresis of seven loci of N. alessandrii was used to estimate genetic diversity, genetic structure and gene flow. Key Results High levels of genetic diversity were found as shown by mean expected heterozygosity (He = 0·182 ± 0·034), percentage of polymorphic loci (Pp = 61·2 %), mean number of alleles per locus (A = 1·8) and mean number of alleles per polymorphic locus (Ap = 2·3). Genetic differentiation was also high (GST = 0·257 and Nm = 0·7). These values are high compared with more widespread congeneric species. Conclusions Despite its endemic status and restricted geographical range N. alessandrii showed high levels of genetic diversity. The observed patterns of diversity are explained in part by historical processes and more recent human fragmentation. PMID:17513870

  2. Yeast and yeast-like fungi associated with dry indehiscent fruits of Nothofagus nervosa in Patagonia, Argentina.

    PubMed

    Fernández, Natalia V; Mestre, M Cecilia; Marchelli, Paula; Fontenla, Sonia B

    2012-04-01

    Nothofagus nervosa (Raulí) is a native tree species that yields valuable timber. It was overexploited in the past and is currently included in domestication and conservation programs. Several research programs have focused on the characterization of epiphytic microorganisms because it has been demonstrated that they can affect plant-pathogen interactions and/or promote plant growth. Although the microbial ecology of leaves has been well studied, less is known about microorganisms occurring on seeds and noncommercial fruits. In this work, we analyzed the yeast and yeast-like fungi present on N. nervosa fruits destined for the propagation of this species, as well as the effects of fruit preservation and seed dormancy-breaking processes on fungal diversity. Morphological and molecular methods were used, and differences between fungal communities were analyzed using a similarity index. A total of 171 isolates corresponding to 17 species were recovered, most of which belong to the phylum Ascomycota. The majority of the species develop mycelia, produce pigments and mycosporines, and these adaptation strategies are discussed. It was observed that the preservation process considerably reduced yeast and yeast-like fungal diversity. This is the first study concerning microbial communities associated with this ecologically and economically important species, and the information presented is relevant to domestication programs.

  3. Ectomycorrhizal fungi enhance nitrogen and phosphorus nutrition of Nothofagus dombeyi under drought conditions by regulating assimilative enzyme activities.

    PubMed

    Alvarez, Maricel; Huygens, Dries; Olivares, Erick; Saavedra, Isabel; Alberdi, Miren; Valenzuela, Eduardo

    2009-08-01

    Drought stress conditions (DC) reduce plant growth and nutrition, restraining the sustainable reestablishment of Nothofagus dombeyi in temperate south Chilean forest ecosystems. Ectomycorrhizal symbioses have been documented to enhance plant nitrogen (N) and phosphorus (P) uptake under drought, but the regulation of involved assimilative enzymes remains unclear. We studied 1-year-old N. dombeyi (Mirb.) Oerst. plants in association with the ectomycorrhizal fungi Pisolithus tinctorius (Pers.) Coker & Couch. and Descolea antartica Sing. In greenhouse experiments, shoot and root dry weights, mycorrhizal colonization, foliar N and P concentrations, and root enzyme activities [glutamate synthase (glutamine oxoglutarate aminotransferase (GOGAT), EC 1.4.1.13-14), glutamine synthetase (GS, EC 6.3.1.2), glutamate dehydrogenase (GDH, EC 1.4.1.2-4), nitrate reductase (NR, EC 1.6.6.1), and acid phosphomonoesterase (PME, EC 3.1.3.1-2)] were determined as a function of soil-water content. Inoculation of N. dombeyi with P. tinctorius and D. antartica significantly stimulated plant growth and increased plant foliar N and P concentrations, especially under DC. Ectomycorrhizal inoculation increased the activity of all studied enzymes relative to non-mycorrhizal plants under drought. We speculate that GDH is a key enzyme involved in the enhancement of ectomycorrhizal carbon (C) availability by fuelling the tricarboxylic acid (TCA) cycle under conditions of drought-induced carbon deficit. All studied assimilative enzymes of the ectomycorrhizal associations, involved in C, N, and P transfers, are closely interlinked and interdependent. The up-regulation of assimilative enzyme activities by ectomycorrhizal fungal root colonizers acts as a functional mechanism to increase seedling endurance to drought. We insist upon incorporating ectomycorrhizal inoculation in existing Chilean afforestation programs. PMID:19470091

  4. Ectomycorrhizal fungi enhance nitrogen and phosphorus nutrition of Nothofagus dombeyi under drought conditions by regulating assimilative enzyme activities.

    PubMed

    Alvarez, Maricel; Huygens, Dries; Olivares, Erick; Saavedra, Isabel; Alberdi, Miren; Valenzuela, Eduardo

    2009-08-01

    Drought stress conditions (DC) reduce plant growth and nutrition, restraining the sustainable reestablishment of Nothofagus dombeyi in temperate south Chilean forest ecosystems. Ectomycorrhizal symbioses have been documented to enhance plant nitrogen (N) and phosphorus (P) uptake under drought, but the regulation of involved assimilative enzymes remains unclear. We studied 1-year-old N. dombeyi (Mirb.) Oerst. plants in association with the ectomycorrhizal fungi Pisolithus tinctorius (Pers.) Coker & Couch. and Descolea antartica Sing. In greenhouse experiments, shoot and root dry weights, mycorrhizal colonization, foliar N and P concentrations, and root enzyme activities [glutamate synthase (glutamine oxoglutarate aminotransferase (GOGAT), EC 1.4.1.13-14), glutamine synthetase (GS, EC 6.3.1.2), glutamate dehydrogenase (GDH, EC 1.4.1.2-4), nitrate reductase (NR, EC 1.6.6.1), and acid phosphomonoesterase (PME, EC 3.1.3.1-2)] were determined as a function of soil-water content. Inoculation of N. dombeyi with P. tinctorius and D. antartica significantly stimulated plant growth and increased plant foliar N and P concentrations, especially under DC. Ectomycorrhizal inoculation increased the activity of all studied enzymes relative to non-mycorrhizal plants under drought. We speculate that GDH is a key enzyme involved in the enhancement of ectomycorrhizal carbon (C) availability by fuelling the tricarboxylic acid (TCA) cycle under conditions of drought-induced carbon deficit. All studied assimilative enzymes of the ectomycorrhizal associations, involved in C, N, and P transfers, are closely interlinked and interdependent. The up-regulation of assimilative enzyme activities by ectomycorrhizal fungal root colonizers acts as a functional mechanism to increase seedling endurance to drought. We insist upon incorporating ectomycorrhizal inoculation in existing Chilean afforestation programs.

  5. Genetic differentiation in spite of high gene flow in the dominant rainforest tree of southeastern Australia, Nothofagus cunninghamii.

    PubMed

    Duncan, C J; Worth, J R P; Jordan, G J; Jones, R C; Vaillancourt, R E

    2016-01-01

    Nothofagus cunninghamii is a long-lived, wind-pollinated tree species that dominates the cool temperate rainforests of southeastern Australia. The species' distribution is more or less continuous in western Tasmania but is fragmented elsewhere. However, it is unknown whether this fragmentation has affected the species' genetic architecture. Thus, we examined N. cunninghamii using 12 nuclear microsatellites and 633 individuals from 18 populations spanning the species' natural range. Typical of wind-pollinated trees, there was low range-wide genetic structure (FST=0.04) consistent with significant gene flow across most of the species' range. However, gene flow was not high enough to overcome the effects of drift across some disjunctions. Victorian populations (separated from Tasmania by the 240 km wide Bass Strait) formed a genetic group distinct from Tasmanian populations, had lower diversity (mean allelic richness (Ar)=5.4 in Victoria versus 6.9 in Tasmania) and were significantly more differentiated from one another than those in Tasmania (FST=0.045 in Victoria versus 0.012 in Tasmania). Evidence for bottlenecking was found in small populations that were at least 20 km from other populations. Interestingly, we found little divergence in microsatellite markers between the extremes of genetically based morphological and physiological altitudinal clines suggesting adaptive differentiation is strongly driven by selection because it is likely to be occurring in the presence of gene flow. Even though the cool temperate rainforests of Australia are highly relictual, the species is relatively robust to population fragmentation due to high levels of genetic diversity and gene flow, especially in Tasmania.

  6. Tree-Ring Stable Isotopes Reveal Twentieth-Century Increases in Water-Use Efficiency of Fagus sylvatica and Nothofagus spp. in Italian and Chilean Mountains

    PubMed Central

    Tognetti, Roberto; Lombardi, Fabio; Lasserre, Bruno; Cherubini, Paolo; Marchetti, Marco

    2014-01-01

    Changes in intrinsic water use efficiency (iWUE) were investigated in Fagus sylvatica and Nothofagus spp. over the last century. We combined dendrochronological methods with dual-isotope analysis to investigate whether atmospheric changes enhanced iWUE of Fagus and Nothofagus and tree growth (basal area increment, BAI) along latitudinal gradients in Italy and Chile. Post-maturation phases of the trees presented different patterns in δ13C, Δ13C, δ18O, Ci (internal CO2 concentration), iWUE, and BAI. A continuous enhancement in isotope-derived iWUE was observed throughout the twentieth century, which was common to all sites and related to changes in Ca (ambient CO2 concentration) and secondarily to increases in temperature. In contrast to other studies, we observed a general increasing trend of BAI, with the exception of F. sylvatica in Aspromonte. Both iWUE and BAI were uncoupled with the estimated drought index, which is in agreement with the absence of enduring decline in tree growth. In general, δ13C and δ18O showed a weak relationship, suggesting the major influence of photosynthetic rate on Ci and δ13C, and the minor contribution of the regulation of stomatal conductance to iWUE. The substantial warming observed during the twentieth century did not result in a clear pattern of increased drought stress along these latitudinal transects, because of the variability in temporal trends of precipitation and in specific responses of populations. PMID:25398040

  7. Using Genome-Wide SNP Discovery and Genotyping to Reveal the Main Source of Population Differentiation in Nothofagus dombeyi (Mirb.) Oerst. in Chile

    PubMed Central

    González, Jorge; Fuentes, Glenda; Alarcón, Diego; Ruiz, Eduardo

    2016-01-01

    Within a woody plant species, environmental heterogeneity has the potential to influence the distribution of genetic variation among populations through several evolutionary processes. In some species, a relationship between environmental characteristics and the distribution of genotypes can be detected, showing the importance of natural selection as the main source of differentiation. Nothofagus dombeyi (Mirb.) Oerst. (Nothofagaceae) is an endemic tree species occurring both in Chile and in Argentina temperate forests. Postglacial history has been studied with chloroplast DNA and evolutionary forces shaping genetic variation patterns have been analysed with isozymes but fine-scale genetic diversity studies are needed. The study of demographic and selection histories in Nothofagus dombeyi requires more informative markers such as single nucleotide polymorphisms (SNP). Genotyping-by-Sequencing tools now allow studying thousands of SNP markers at reasonable prices in nonmodel species. We investigated more than 10 K SNP loci for signatures of local adaptation and showed that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this nonmodel woody species. PMID:27446942

  8. Using Genome-Wide SNP Discovery and Genotyping to Reveal the Main Source of Population Differentiation in Nothofagus dombeyi (Mirb.) Oerst. in Chile.

    PubMed

    Hasbún, Rodrigo; González, Jorge; Iturra, Carolina; Fuentes, Glenda; Alarcón, Diego; Ruiz, Eduardo

    2016-01-01

    Within a woody plant species, environmental heterogeneity has the potential to influence the distribution of genetic variation among populations through several evolutionary processes. In some species, a relationship between environmental characteristics and the distribution of genotypes can be detected, showing the importance of natural selection as the main source of differentiation. Nothofagus dombeyi (Mirb.) Oerst. (Nothofagaceae) is an endemic tree species occurring both in Chile and in Argentina temperate forests. Postglacial history has been studied with chloroplast DNA and evolutionary forces shaping genetic variation patterns have been analysed with isozymes but fine-scale genetic diversity studies are needed. The study of demographic and selection histories in Nothofagus dombeyi requires more informative markers such as single nucleotide polymorphisms (SNP). Genotyping-by-Sequencing tools now allow studying thousands of SNP markers at reasonable prices in nonmodel species. We investigated more than 10 K SNP loci for signatures of local adaptation and showed that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this nonmodel woody species. PMID:27446942

  9. Non-gradual variation in colour morphs of the strawberry poison frog Dendrobates pumilio: genetic and geographical isolation suggest a role for selection in maintaining polymorphism.

    PubMed

    Rudh, Andreas; Rogell, Björn; Höglund, Jacob

    2007-10-01

    The relative roles that geographical isolation and selection play in driving population divergence remain one of the central questions in evolutionary biology. We approached this question by investigating genetic and morphological variation among populations of the strawberry poison frog, Dendrobates pumilio, in the Bocas del Toro archipelago, Panama. We found significant population genetic structure and isolation by distance based on amplified fragment length polymorphism markers. Snout vent length (SVL), coloration and the extent and size of dorsal black spots showed large variation among the studied populations. Differences in SVL correlated with genetic distance, whereas black spot patterns and other coloration parameters did not. Indeed, the latter characters were observed to be dramatically different between contiguous populations located on the same island. These results imply that neutral divergence among populations may account for the genetic patterns based on amplified fragment length polymorphism markers and SVL. However, selective pressures need to be invoked in order to explain the extraordinary variation in spot size and coverage, and coloration. We discuss the possibility that the observed variation in colour morphs is a consequence of a combination of local variation in both natural selection on an aposematic signal towards visual predators and sexual selection generated by colour morph-specific mate preferences. PMID:17868297

  10. Post-transcriptional regulation through the HO 3′-UTR by Mpt5, a yeast homolog of Pumilio and FBF

    PubMed Central

    Tadauchi, Tomofumi; Matsumoto, Kunihiro; Herskowitz, Ira; Irie, Kenji

    2001-01-01

    Drosophila Pumilio (Pum) and Caenorhabditis elegans FBF bind to the 3′-untranslated region (3′-UTR) of their target mRNAs and repress translation. Pum and FBF are members of a large and evolutionarily conserved protein family, the Puf family, found in Drosophila, C.elegans, humans and yeasts. Budding yeast, Saccharomyces cerevisiae, has five proteins with conserved Puf motifs: Mpt5/Uth4, Ygl014w, Yll013c, Jsn1 and Ypr042c. Here we report that Mpt5 negatively regulates expression of the HO gene. Loss of MPT5 increased expression of reporter genes integrated into the ho locus, whereas overexpression of MPT5 decreased expression. Repression required the 3′-UTR of HO, which contains a tetranucleotide, UUGU, also found in the binding sites of Pum and FBF. Mutation of UUGU to UACU in the HO 3′-UTR abolished Mpt5-mediated repression. Studies using a three-hybrid assay for RNA binding indicate that Mpt5 binds to the 3′-UTR of HO mRNA containing a UUGU sequence but not a UACU sequence. These observations suggest that the yeast Puf homolog, Mpt5, negatively regulates HO expression post- transcriptionally. PMID:11157761

  11. Functional Genomic Characterization of mRNAs Associated with TcPUF6, a Pumilio-like Protein from Trypanosoma cruzi*S⃞

    PubMed Central

    Dallagiovanna, Bruno; Correa, Alejandro; Probst, Christian M.; Holetz, Fabiola; Smircich, Pablo; de Aguiar, Alessandra Melo; Mansur, Fernanda; da Silva, Claudio Vieira; Mortara, Renato A.; Garat, Beatriz; Buck, Gregory A.; Goldenberg, Samuel; Krieger, Marco A.

    2008-01-01

    Trypanosoma cruzi is the protozoan parasite that causes Chagas disease or American trypanosomiasis. Kinetoplastid parasites could be considered as model organisms for studying factors involved in posttranscriptional regulation because they control gene expression almost exclusively at this level. The PUF (Pumilio/FBF1) protein family regulates mRNA stability and translation in eukaryotes, and several members have been identified in trypanosomatids. We used a ribonomic approach to identify the putative target mRNAs associated with TcPUF6, a member of the T. cruzi PUF family. TcPUF6 is expressed in discrete sites in the cytoplasm at various stages of the parasite life cycle and is not associated with the translation machinery. The overexpression of a tandem affinity purification-tagged TcPUF6 protein allowed the identification of associated mRNAs by affinity purification assays and microarray hybridization yielding nine putative target mRNAs. Whole expression analysis of transfected parasites showed that the mRNAs associated with TcPUF6 were down-regulated in populations overexpressing TcPUF6. The association of TcPUF6 with the TcDhh1 helicase in vivo and the cellular co-localization of these proteins in epimastigote forms suggest that TcPUF6 promotes degradation of its associated mRNAs through interaction with RNA degradation complexes. Analysis of the mRNA levels of the putative TcPUF6-regulated genes during the parasite life cycle showed that their transcripts were up-regulated in metacyclic trypomastigotes. In these infective forms no co-localization between TcPUF6 and TcDhh1 was observed. Our results suggest that TcPUF6 regulates the half-lives of its associated transcripts via differential association with mRNA degradation complexes throughout its life cycle. PMID:18056709

  12. The Importance of the Nothofagus Forest on Snowmelt Process linked to floods in Mountain Basins of Tierra del Fuego, Argentina as Input for Land Use Policies.

    NASA Astrophysics Data System (ADS)

    Iturraspe, R. J.; Urciuolo, A. B.; Lofiego, R.

    2007-05-01

    The conception and application of policies and best practices for the appropriate land use from the view point of extreme floods attenuation, must be based on scientist acknowledge of the basin response, reaching each one of the hydrological cycle's components. That condition is necessary as a start point for an integrated intersectoral management of water and forest resources at the basin scale, especially when forest logging or forest urbanization appear as land use alternatives with socioeconomic importance, confronting the natural roll of the forest in the basin. Within this framework, this article analyzes the forest importance on the seasonal snow-pack and snow-melting process in the mountain basin environment of Tierra del Fuego Island, Argentina, where a mixed rain-snow hydrological regimen and a canopy of native Nothofagus forest are basic features considered. Extreme floods events are related to heavy rain and snow-melting combination. In theory, the worst scenario is the exceptional rain occurrence at the moment of the maximum snow storage, air temperature higher than 0ºC in the whole basin, and previous wet conditions. On this scenario we analyze aspects that indicate forest influences on the snow pack distribution and evolution which are favorable to the attenuation of the intensity of melting process which are induced by rain and temperate air mass. Results were obtained in the context of the EPIC FORCE (EU) Project.

  13. Establishment of ectomycorrhizal fungal community on isolated Nothofagus cunninghamii seedlings regenerating on dead wood in Australian wet temperate forests: does fruit-body type matter?

    PubMed

    Tedersoo, Leho; Gates, Genevieve; Dunk, Chris W; Lebel, Teresa; May, Tom W; Kõljalg, Urmas; Jairus, Teele

    2009-08-01

    Decaying wood provides an important habitat for animals and forms a seed bed for many shade-intolerant, small-seeded plants, particularly Nothofagus. Using morphotyping and rDNA sequence analysis, we compared the ectomycorrhizal fungal community of isolated N. cunninghamii seedlings regenerating in decayed wood against that of mature tree roots in the forest floor soil. The /cortinarius, /russula-lactarius, and /laccaria were the most species-rich and abundant lineages in forest floor soil in Australian sites at Yarra, Victoria and Warra, Tasmania. On root tips of seedlings in dead wood, a subset of the forest floor taxa were prevalent among them species of /laccaria, /tomentella-thelephora, and /descolea, but other forest floor dominants were rare. Statistical analyses suggested that the fungal community differs between forest floor soil and dead wood at the level of both species and phylogenetic lineage. The fungal species colonizing isolated seedlings on decayed wood in austral forests were taxonomically dissimilar to the species dominating in similar habitats in Europe. We conclude that formation of a resupinate fruit body type on the underside of decayed wood is not necessarily related to preferential root colonization in decayed wood. Rather, biogeographic factors as well as differential dispersal and competitive abilities of fungal taxa are likely to play a key role in structuring the ectomycorrhizal fungal community on isolated seedlings in decaying wood. PMID:19377891

  14. Dynamic light use and protection from excess light in upper canopy and coppice leaves of Nothofagus cunninghamii in an old growth, cool temperate rainforest in Victoria, Australia.

    PubMed

    Tausz, Michael; Warren, Charles R; Adams, Mark A

    2005-01-01

    Responses to simulated sunflecks were examined in upper canopy and coppice leaves of Nothofagus cunninghamii growing in an old-growth rainforest gully in Victoria, Australia. Shaded leaves were exposed to a sudden increase in irradiance from 20 to 1500 micromol m(-2) s(-1). Gas exchange and chlorophyll fluorescence were measured during a 10 min simulated sunfleck and, in the ensuing dark treatment, we examined the recovery of PS II efficiency and the conversion state of xanthophyll cycle pigments. Photosynthetic induction was rapid compared with tropical and northern hemisphere species. Stomatal conductance was relatively high in the shade and stomata did not directly control photosynthetic induction under these conditions. During simulated sunflecks, zeaxanthin was formed rapidly and photochemical efficiency was reduced. These processes were reversed within 30 min in coppice leaves, but this took longer in upper canopy leaves. Poor drought tolerance and achieving a positive carbon balance in a shaded canopy may be functionally related to high stomatal conductance in the shade in N. cunninghamii. The more persistent reduction in photochemical efficiency of upper canopy leaves, which means less efficient light use in subsequent shade periods, but stronger protection from high light, may be related to the generally higher irradiance and longer duration of sunflecks in the upper canopy, but potentially reduces carbon gain during shade periods by 30%.

  15. Intraspecific Relationships among Wood Density, Leaf Structural Traits and Environment in Four Co-Occurring Species of Nothofagus in New Zealand

    PubMed Central

    Richardson, Sarah J.; Allen, Robert B.; Buxton, Rowan P.; Easdale, Tomás A.; Hurst, Jennifer M.; Morse, Christopher W.; Smissen, Rob D.; Peltzer, Duane A.

    2013-01-01

    Plant functional traits capture important variation in plant strategy and function. Recent literature has revealed that within-species variation in traits is greater than previously supposed. However, we still have a poor understanding of how intraspecific variation is coordinated among different traits, and how it is driven by environment. We quantified intraspecific variation in wood density and five leaf traits underpinning the leaf economics spectrum (leaf dry matter content, leaf mass per unit area, size, thickness and density) within and among four widespread Nothofagus tree species in southern New Zealand. We tested whether intraspecific relationships between wood density and leaf traits followed widely reported interspecific relationships, and whether variation in these traits was coordinated through shared responses to environmental factors. Sample sites varied widely in environmental variables, including soil fertility (25–900 mg kg–1 total P), precipitation (668–4875 mm yr–1), temperature (5.2–12.4 °C mean annual temperature) and latitude (41–46 °S). Leaf traits were strongly correlated with one another within species, but not with wood density. There was some evidence for a positive relationship between wood density and leaf tissue density and dry matter content, but no evidence that leaf mass or leaf size were correlated with wood density; this highlights that leaf mass per unit area cannot be used as a surrogate for component leaf traits such as tissue density. Trait variation was predicted by environmental factors, but not consistently among different traits; e.g., only leaf thickness and leaf density responded to the same environmental cues as wood density. We conclude that although intraspecific variation in wood density and leaf traits is strongly driven by environmental factors, these responses are not strongly coordinated among functional traits even across co-occurring, closely-related plant species. PMID:23527041

  16. Population genetic structure, genetic diversity, and natural history of the South American species of Nothofagus subgenus Lophozonia (Nothofagaceae) inferred from nuclear microsatellite data

    PubMed Central

    Vergara, Rodrigo; Gitzendanner, Matthew A; Soltis, Douglas E; Soltis, Pamela S

    2014-01-01

    The effect of glaciation on the levels and patterns of genetic variation has been well studied in the Northern Hemisphere. However, although glaciation has undoubtedly shaped the genetic structure of plants in the Southern Hemisphere, fewer studies have characterized the effect, and almost none of them using microsatellites. Particularly, complex patterns of genetic structure might be expected in areas such as the Andes, where both latitudinal and altitudinal glacial advance and retreat have molded modern plant communities. We therefore studied the population genetics of three closely related, hybridizing species of Nothofagus (N. obliqua, N. alpina, and N. glauca, all of subgenus Lophozonia; Nothofagaceae) from Chile. To estimate population genetic parameters and infer the influence of the last ice age on the spatial and genetic distribution of these species, we examined and analyzed genetic variability at seven polymorphic microsatellite DNA loci in 640 individuals from 40 populations covering most of the ranges of these species in Chile. Populations showed no significant inbreeding and exhibited relatively high levels of genetic diversity (HE = 0.502–0.662) and slight, but significant, genetic structure (RST = 8.7–16.0%). However, in N. obliqua, the small amount of genetic structure was spatially organized into three well-defined latitudinal groups. Our data may also suggest some introgression of N. alpina genes into N. obliqua in the northern populations. These results allowed us to reconstruct the influence of the last ice age on the genetic structure of these species, suggesting several centers of genetic diversity for N. obliqua and N. alpina, in agreement with the multiple refugia hypothesis. PMID:25360279

  17. Tree size and light availability increase photochemical instead of non-photochemical capacities of Nothofagus nitida trees growing in an evergreen temperate rain forest.

    PubMed

    Coopman, Rafael E; Briceño, Verónica F; Corcuera, Luis J; Reyes-Díaz, Marjorie; Alvarez, Daniela; Sáez, Katherine; García-Plazaola, José I; Alberdi, Miren; Bravo, León A

    2011-10-01

    Nothofagus nitida (Phil.) Krasser (Nothofagaceae) regenerates under the canopy in microsites protected from high light. Nonetheless, it is common to find older saplings in clear areas and adults as emergent trees of the Chilean evergreen forest. We hypothesized that this shade to sun transition in N. nitida is supported by an increase in photochemical and non-photochemical energy dissipation capacities of both photosystems in parallel with the increase in plant size and light availability. To dissect the relative contribution of light environment and plant developmental stage to these physiological responses, the photosynthetic performance of both photosystems was studied from the morpho-anatomical to the biochemical level in current-year leaves of N. nitida plants of different heights (ranging from 0.1 to 7 m) growing under contrasting light environments (integrated quantum flux (IQF) 5-40 mol m(-2). Tree height (TH) and light environment (IQF) independently increased the saturated electron transport rates of both photosystems, as well as leaf and palisade thickness, but non-photochemical energy flux, photoinhibition susceptibility, state transition capacity, and the contents of D1 and PsbS proteins were not affected by IQF and TH. Spongy mesophyll thickness and palisade cell diameter decreased with IQF and TH. A(max), light compensation and saturation points, Rubisco and nitrogen content (area basis) only increased with light environment (IQF), whereas dark respiration (R(d)) decreased slightly and relative chlorophyll content was higher in taller trees. Overall, the independent effects of more illuminated environment and tree height mainly increased the photochemical instead of the non-photochemical energy flux. Regardless of the photochemical increase with TH, carbon assimilation only significantly improved with higher IQF. Therefore it seems that mainly acclimation to the light environment supports the phenotypic transition of N. nitida from shade to

  18. [Basic family health program in Magdalena Medio y Bajo].

    PubMed

    Murad, R

    1992-12-01

    The Program of Information, Education, and Services for Basic Family Health Care in Magdalena Medio and Bajo was designed to increase knowledge and use of contraception and to improve basic health practices and nutrition in the region, which includes municipios belonging to 9 different departments and a total population of 1,720,000. Poverty levels in the area are high. During the 1st year of the project, which was underway from February 1988-May 1991, home visits were made to inform each family about basic family health, to weigh and measure children under 5 not receiving health care elsewhere, and to refer families to the nearest health services. Talks were presented to small groups on family planning, intestinal parasites, sexually transmitted diseases, nutrition, vaccination, cancer prevention, malaria, acute diarrhea, and acute respiratory infection. Community workshops were presented in the 2nd year. Community distribution posts were created for contraceptive and other health product distribution. Information and communication materials from PROFAMILIA were used, and other materials were specially designed for the project by the Foundation for Development of Health Education in Colombia. PROFAMILIA's system of service statistics was used for quantitative evaluation of the information and education activities and sales of contraceptives, antiparasitics, and oral rehydration packets of each instructor. In the 3 years of the program, 89.086 cycles of pills, 398,772 condoms, 29,080 vaginal tablets, 209.791 antiparasitics, and 49,305 oral rehydration packets were sold. 9295 talks were presented to 143,227 residents of the region. 22,000 children were enrolled in the growth monitoring program, and almost 40,000 women were referred for prenatal care and cytology. The instructors gave 900 talks to distributors of contraceptives, antiparasitics, and oral rehydration packets. Surveys of women aged 15-49 residing in the municipios covered by the project were conducted

  19. Morphology, geology and geochemistry of the "Salar del Gran Bajo del Gualicho" (Rio Negro, Argentina)

    USGS Publications Warehouse

    Angelucci, A.; Barbieri, M.; Brodtkorb, A.; Ciccacci, S.; Civitelli, G.; De Barrio, R.; Di, Filippo M.; Fredi, P.; Friedman, I.; Lombardi, S.; Schalamuk, A.I.; Toro, B.

    1996-01-01

    A multidisciplinary study of the Gran Bajo del Gualicho area (Rio Negro - Argentina) was carried out; the aim was to delineate its geological and geomorphological evolution and to estabilish the genesis of salts filling the depression. Climatic conditions were analized first to individuate their role in the present morphogenetic processes; moreover the main morphological features of present landscape were examined as well as the stratigraphy of the outcropping formations, and of the Gran Bajo del Gualicho Formation in particular. Finally, a possible geomorphological evolution of the studied area was traced. Geophysical analyses allowed to estabilish that the paleosurface shaped on the crystalline basement is strongly uneven and shows evidence of the strong tectonic phases it underwent. The result of isotope analyses confirmed that the salt deposits on the Gran Bajo del Gualicho bottom were produced by fresh water evaporation, while strontium isotope ratio suggested that such waters were responsible for solubilization of more ancient evaporitic deposits.

  20. [Crustaceans associated to macroalgae in Bajo Pepito, Isla Mujeres, Mexican Caribbean].

    PubMed

    Campos Vázquez, C

    2000-01-01

    Crustaceans associated with macroalgae were collected for one year by scuba diving in Bajo Pepito, Isla Mujeres, mexican Caribbean. A total of 148 organisms were found: three orders, 11 families, 18 genera and 19 species in nine types of associations. The order with highest abundance was Isopoda (112), followed by Amphipoda (20) and Decapoda (16).

  1. GPS deformation rates in the Bajo Segura Basin (NE of the Eastern Betic Shear Zone, SE Spain)

    NASA Astrophysics Data System (ADS)

    Jesús Borque, María; Sánchez-Alzola, Alberto; Estévez, Antonio; García-Tortosa, Francisco J.; Martín-Rojas, Iván; Molina, Sergio; Alfaro, Pedro; Rodríguez-Caderot, Gracia; de Lacy, Clara; García-Armenteros, Juan Antonio; Avilés, Manuel; Herrera, Antonio; Rosa-Cintas, Sergio; Gil, Antonio J.

    2014-05-01

    The Bajo Segura Basin, located in the NE end of the Eastern Betic Shear Zone, is one of the areas with highest seismic activity of the Iberian Peninsula. It is bounded by the Crevillente Fault to the north and the Bajo Segura Fault to the south, and it is characterized by a Late Miocene to Quaternary folded cover. We estimate the present-day deformation of the study area from a GPS network with 11 sites. Observation campaigns were carried out four times (June 1999, September 2001, September 2002 and September 2013). We used the 6.2 version of GIPSY-OASIS software to process GPS data in Precise Point Positioning mode (PPP). In order to obtain the position time series in the whole period of these episodic campaigns, all the GPS observations from 1999 to 2013 campaigns were processed with an identical standard procedure. We compared our velocity field estimation with respect to GEODVEL tectonic model to obtain the residual velocity field of the Bajo Segura Basin. We estimated a ~N-S shortening with deformation rates varying between 0.2 and 0.6 mm/yr. These results are consistent with local geological deformation rates although slightly higher. They also fit well with regional geodetic data estimated for the Western Mediterranean.

  2. Timescales of Porphyry Cu Formation: Bajo de la Alumbrera, NW Argentina

    NASA Astrophysics Data System (ADS)

    Buret, Y.; Von Quadt, A.; Heinrich, C. A.; Peytcheva, I.

    2014-12-01

    Using high-precision U-Pb dating we are potentially able to determine timescales of porphyry emplacement and ore formation. Previous studies have suggested timescales of porphyry Cu formation ranging from <100 yr, based on modelling diffusive equilibrium between fluids and altered rocks [1], to as much as 1 Ma using U-Pb LA-ICP-MS and SHRIMP dating techniques on zircons [2], [3]. In contrast recent numerical simulations suggest Cu precipitation occurs in the range of 50-100 ka [4]. Therefore in order to better constrain timescales of porphyry Cu formation, we apply high precision U-Pb zircon geochronology, using the youngest zircon date to estimate the emplacement age of each porphyry [5].This study focuses on the ~7 Ma Bajo de la Alumbrera Cu-Au deposit, NW Argentina. The deposit consists of a composite stock of dacitic porphyries. The relative timing of each porphyry intrusion is established based on clear cross-cutting relationships between different porphyry intrusions, which include the pre-mineralisation P2 porphyry, pre-syn-minerlisation EP3 porphyry, and the post-mineralisation LP3 and P4 porphyries.Single zircon crystals from individual porphyry intrusions (P2, EP3, LP3, P4) in the Alumbrera deposit have been dated using CA-ID-TIMS, employing the ET2535 tracer solution for maximum precision and accuracy. All porphyries display protracted zircon crystal growth over 100-200 ka timescales. Using the youngest zircons from each of the porphyry intrusions, Cu mineralisation occurred on 10 ka timescales, similar to those proposed by recent numerical predictions [4]. Trace element and Hf isotopic analyses may reveal geochemical distinctions within the porphyry intrusions and record temporal changes in the magmatic evolution. References: [1] Cathles and Shannon (2007) EPSL 262:92-108; [2] Ballard et al. (2001) Geology 29:383-386; [3] Harris et al. (2008) Min Dep 43: 295-314; [4] Weis et al. (2012) Science 338: 1613-1616; [5] von Quadt et al. (2011) Geology 39: 731-734.

  3. A Long-Lived Porphyry Ore Deposit and Associated Upper Crustal Silicic Magma Body, Bajo de la Alumbrera, Argentina

    NASA Astrophysics Data System (ADS)

    Harris, A. C.; Allen, C. M.; Reiners, P. W.; Dunlap, W. J.; Cooke, D. R.; Campbell, I. H.; White, N. C.

    2004-05-01

    Porphyry Cu deposits form within and adjacent to small porphyritic intrusions that are apophyses to larger silicic magma bodies that reside in the upper parts of the Earth's crusts. Centred on these intrusions are hydrothermal systems of exsolved magmatic fluid with a carapace of convectively circulating meteoric water. We have applied several different dating techniques to assess the longevity of the magmatic-hydrothermal system and to define the cooling history of porphyry intrusions at the Bajo de la Alumbrera porphyry Cu-Au deposit, Argentina. The closure temperatures of these techniques range from 800oC (zircon U-Pb) to ~70oC (apatite (U-Th)/He; Fig. 1). The resulting cooling history indicates that the magmatic-hydrothermal system cooled to ca. 200oC by ~1.5 m.y. after the last porphyry intrusion (i.e., 6.96±0.09 Ma; U-Pb zircon age). Based on (U-Th)/He apatite data (closure temperature ~60-70oC), exposure and cessation of the system occurred before 4 Ma. The longevity of the magmatic-hydrothermal system indicated by these results is inconsistent with accepted mechanisms for porphyry Cu deposit formation. Depending on wallrock permeability, depth and cooling method, a 2 km wide by 3 km high intrusion has been predicted to cool between 0.01 to 0.1 m.y. (marked as the grey interval; Cathles et al., 1997 Economic Geology). We have obtained numerous age determinations younger than the U-Pb zircon age of the last known intrusion at Bajo de la Alumbrera. These imply that simple cooling of the small, mineralized porphyries did not happen. For the magmatic-hydrothermal system to have been sustained for longer than 0.1 m.y., either 1) younger small intrusions have been episodically emplaced below the youngest known intrusions, thus prolonging heat flow, or 2) fluids derived from a deeper and larger parental intrusion have been episodically discharged through the ore deposit long after the porphyry intrusion had lost its available heat. In either case, the longevity of

  4. Relationship between Bajo Pobre and Chon Aike formations (Deseado Massif, Patagonia, Argentina):a melt inclusions study

    NASA Astrophysics Data System (ADS)

    Busà, T.; Bellieni, G.; Fernandez, R.; Hecheveste, H.; Piccirillo, E. M.

    2003-04-01

    The Deseado Massif covers the centre-east of the Santa Cruz Province, in the extra-Andean Patagonia. Although the Deseado Massif is mainly composed of silicic volcanic rocks (Chon Aike Formation, CA; 151.5 ±0.5 - 177.8 ±0.4 Ma), mafic and intermediate volcanites (Bajo Pobre Formation, BP; 152.7 ±0.5 and 164 ±0.3 Ma) outcrop largely in the central part of the Massif. In this paper quarz-trapped melt inclusions (rhyolitic in composition) from selected samples of the BP and the CA are analysed. On the basis of major elements content, for BP the sequence from andesite (BP whole rock) to ryholite (trapped as inclusions in quartz) can be modelled by simple fractional crystallisation of ortho- and clinopyroxene, plagioclase, quartz and apatite. As regards trace elements, a good calculated/measured ratio (around 1 ±0.2) is obtained assuming only a relatively high apatite fractionation. Since the apatite fractionation amount is not acceptable for major elements, the evolution of BP Formation cannot be modelled by a simple process of fractional crystallisation, and a contamination process probably occurred. The sequence from BP to CA cannot be modelled by fractional crystallisation. 30% batch melting of BP andesite (BP whole rock) produces a magma from which the CA ryholites (trapped as inclusions in quartz) can be obtained by Rayleigh fractional crystallisation of ortho- and clinopyroxene, plagioclase, magnetite, quartz, apatite and small amounts of zircon and minor allanite. Since the latter one was not observed in the analysed sample, a contamination process during magma evolution cannot be completely excluded. Finally, on the basis of the different trace elements concentration (Nb anomaly, different content in LILE, B/Be and B/Nb), it is possible to suppose that, at the time of the BP and CA emplacement, a changing in the tectonic setting, from subduction to a lithospheric extension, was active.

  5. Chronic kidney disease and associated risk factors in the Bajo Lempa region of El Salvador: Nefrolempa study, 2009.

    PubMed

    Orantes, Carlos M; Herrera, Raúl; Almaguer, Miguel; Brizuela, Elsy G; Hernández, Carlos E; Bayarre, Héctor; Amaya, Juan C; Calero, Denis J; Orellana, Patricia; Colindres, Rosa M; Velázquez, María E; Núñez, Sonia G; Contreras, Verónica M; Castro, Bertha E

    2011-10-01

    INTRODUCCIÓN En El Salvador, la enfermedad renal crónica terminal es la causa principal de muerte hospitalaria en adultos, la segunda causa de muerte en los hombres y la quinta causa principal de muerte entre adultos de ambos sexos en la población general. OBJETIVO Identificar los factores de riesgo de la enfermedad renal crónica y los marcadores de daño renovascular en orina, medir la función renal y caracterizar la prevalencia de enfermedad renal crónica en personas X18 años de edad en la región del Bajo Lempa en El Salvador. METODOS Se realizó un estudio epidemiológico transversal y analítico de la enfermedad renal crónica y los factores de riesgo asociados en individuos con edades X18 años por medio de pesquisa activa en la Región del Bajo Lempa, una zona costera rural en El Salvador. Se efectuaron visitas casa por casa y consultas médicas. Se recolectaron datos epidemiológicos y clínicos que incluían: historia clínica personal y familiar para la enfermedad; factores de riesgo biológicos, de conducta, sociales y ambientales; mediciones físicas; análisis de orina buscando marcadores de daño renovascular y exámenes de sangre (creatinina y glucosa en suero, lipidograma). La tasa de filtración glomerular se calculó usando la fórmula de MDRD (sigla en inglés de Modificación de la Dieta en la Enfermedad Renal). La confirmación de casos de enfermedad renal crónica se realizó en un período de tres meses. Se utilizó la regresión logística múltiple para analizar los datos. RESULTADOS Se estudiaron un total de 375 familias y 775 individuos (343 hombres, 432 mujeres), el 88,3% del total de la población residente en la región. Se observó una elevada prevalencia de factores de riesgo: diabetes mellitus en 10,3%; hipertensión en 16,9%; antecedentes familiares de enfermedad renal crónica en 21,6%; dislipidemias en 63,1%; sobrepeso en 34%; obesidad en 22,4%; síndrome metabólico en 28,8%; uso de medicamentos anti-inZ amatorios no

  6. Asháninka medicinal plants: a case study from the native community of Bajo Quimiriki, Junín, Peru

    PubMed Central

    2010-01-01

    Background The Asháninka Native Community Bajo Quimiriki, District Pichanaki, Junín, Peru, is located only 4 km from a larger urban area and is dissected by a major road. Therefore the loss of traditional knowledge is a main concern of the local headman and inhabitants. The present study assesses the state of traditional medicinal plant knowledge in the community and compares the local pharmacopoeia with the one from a related ethnic group. Methods Fieldwork was conducted between July and September 2007. Data were collected through semi-structured interviews, collection of medicinal plants in the homegardens, forest walks, a walk along the river banks, participant observation, informal conversation, cross check through voucher specimens and a focus group interview with children. Results Four-hundred and two medicinal plants, mainly herbs, were indicated by the informants. The most important families in terms of taxa were Asteraceae, Araceae, Rubiaceae, Euphorbiaceae, Solanaceae and Piperaceae. Eighty-four percent of the medicinal plants were wild and 63% were collected from the forest. Exotics accounted to only 2% of the medicinal plants. Problems related to the dermal system, digestive system, and cultural belief system represented 57% of all the medicinal applications. Some traditional healers received non-indigenous customers, using their knowledge as a source of income. Age and gender were significantly correlated to medicinal plant knowledge. Children knew the medicinal plants almost exclusively by their Spanish names. Sixteen percent of the medicinal plants found in this community were also reported among the Yanesha of the Pasco Region. Conclusions Despite the vicinity to a city, knowledge on medicinal plants and cultural beliefs are still abundant in this Asháninka Native Community and the medicinal plants are still available in the surroundings. Nevertheless, the use of Spanish names for the medicinal plants and the shift of healing practices towards a

  7. From a long-lived upper-crustal magma chamber to rapid porphyry copper emplacement: Reading the geochemistry of zircon crystals at Bajo de la Alumbrera (NW Argentina)

    NASA Astrophysics Data System (ADS)

    Buret, Yannick; von Quadt, Albrecht; Heinrich, Christoph; Selby, David; Wälle, Markus; Peytcheva, Irena

    2016-09-01

    The formation of world class porphyry copper deposits reflect magmatic processes that take place in a deeper and much larger underlying magmatic system, which provides the source of porphyry magmas, as well as metal and sulphur-charged mineralising fluids. Reading the geochemical record of this large magmatic source region, as well as constraining the time-scales for creating a much smaller porphyry copper deposit, are critical in order to fully understand and quantify the processes that lead to metal concentration within these valuable mineral deposits. This study focuses on the Bajo de la Alumbrera porphyry copper deposit in Northwest Argentina. The deposit is centred on a dacitic porphyry intrusive stock that was mineralised by several pulses of porphyry magma emplacement and hydrothermal fluid injections. To constrain the duration of ore formation, we dated zircons from four porphyry intrusions, including pre-, syn- and post-mineralisation porphyries based on intersection relations between successive intrusion and vein generations, using high precision CA-ID-TIMS. Based on the youngest assemblages of zircon grains, which overlap within analytical error, all four intrusions were emplaced within 29 ka, which places an upper limit on the total duration of hydrothermal mineralisation. Re/Os dating of hydrothermal molybdenite fully overlaps with this high-precision age bracket. However, all four porphyries contain zircon antecrysts which record protracted zircon crystallisation during the ∼200 ka preceding the emplacement of the porphyries. Zircon trace element variations, Ti-in-zircon temperatures, and Hf isotopic compositions indicate that the four porphyry magmas record a common geochemical and thermal history, and that the four intrusions were derived from the same upper-crustal magma chamber. Trace element zoning within single zircon crystals confirms a fractional crystallisation trend dominated by titanite and apatite crystallisation. However, zircon

  8. Ecology of cultivable yeasts in pristine forests in northern Patagonia (Argentina) influenced by different environmental factors.

    PubMed

    Mestre, María Cecilia; Fontenla, Sonia; Rosa, Carlos A

    2014-06-01

    Environmental factors influencing the occurrence and community structure of soil yeasts in forests are not well studied. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influenced by volcanic activity. The present work aimed to study the ecology of soil yeast communities from pristine forests influenced by different environmental factors (precipitation, physicochemical properties of soil, tree species, soil region, and season). The survey was performed in 4 northern Patagonian forests: 2 dominated by Nothofagus pumilio and 2 by Nothofagus antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics, such as dominant plant species, nutrient availability, and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils, Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil, and capsulated yeasts such as Cryptococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics but the result of complex interactions of factors including natural disturbances like volcanic activity.

  9. The phylogenetic position of poroid Hymenochaetaceae (Hymenochaetales, Basidiomycota) from Patagonia, Argentina.

    PubMed

    Rajchenberg, Mario; Pildain, María Belén; Bianchinotti, María V; Barroetaveña, Carolina

    2015-01-01

    Six poroid Hymenochaetaceae from Patagonia, Argentina, were studied phylogenetically with nuc rDNA internal transcribed spacer (ITS) and partial 28S rDNA sequences, together with morphological data. Two new genera and a new species are introduced as well as two new combinations proposed. Arambarria destruens gen. et sp. nov. is proposed for a taxon fruiting on fallen or standing, dead Diostea juncea and Lomatia hirsuta and previously recorded erroneously as Inocutis jamaicensis; it is distinguished by annual, effused to effused-reflexed basidiomes forming pilei, a monomitic hyphal system, thick-walled and yellowish basidiospores (brownish chestnut in potassium hydroxide solution), lack of a granular core in the context and lack of setoid elements. Nothophellinus gen. nov. is proposed to accommodate Phellinus andinopatagonicus, the main white wood-rotting polypore of standing Nothofagus pumilio and also an important wood-decayer of other Nothofagus species from southern Argentina and Chile. It is morphologically similar to Phellopilus (type species P. nigrolimitatus) but differs by lacking setae. The new combinations Pseudoinonotus crustosus and Phellinopsis andina are proposed for Inonotus crustosus and Phellinus andinus, respectively. Phellinus livescens, which decays the sapwood of several standing Nothofagus species, is closely related to Phellinus uncisetus, a Neotropical species related to Fomitiporia; for the time being P. livescens is retained in Phellinus sensu lato. An unidentified taxon responsible for a white heart-rot in living Austrocedrus chilensis grouped with Phellinus caryophyllii and Fulvifomes inermis, but its generic affinities remain ambiguous. Transmission electron microscopy studies confirm this unidentified taxon has an imperforate parenthesome, which is typical of the Hymenochaetaceae.

  10. Histology and Ultrastructure of Transitional Changes in Skin Morphology in the Juvenile and Adult Four-Striped Mouse (Rhabdomys pumilio)

    PubMed Central

    Stewart, Eranée; Ajao, Moyosore Salihu

    2013-01-01

    The four-striped mouse has a grey to brown coloured coat with four characteristic dark stripes interspersed with three lighter stripes running along its back. The histological differences in the skin of the juvenile and adult mouse were investigated by Haematoxylin and Eosin and Masson Trichrome staining, while melanocytes in the skin were studied through melanin-specific Ferro-ferricyanide staining. The ultrastructure of the juvenile skin, hair follicles, and melanocytes was also explored. In both the juvenile and adult four-striped mouse, pigment-containing cells were observed in the dermis and were homogeneously dispersed throughout this layer. Apart from these cells, the histology of the skin of the adult four-striped mouse was similar to normal mammalian skin. In the juvenile four-striped mouse, abundant hair follicles of varying sizes were observed in the dermis and hypodermis, while hair follicles of similar size were only present in the dermis of adult four-striped mouse. Ultrastructural analysis of juvenile hair follicles revealed that the arrangement and differentiation of cellular layers were typical of a mammal. This study therefore provides unique transition pattern in the four-striped mouse skin morphology different from the textbook description of the normal mammalian skin. PMID:24288469

  11. Extreme environments in the forests of Ushuaia, Argentina

    NASA Astrophysics Data System (ADS)

    D'Antoni, Hector; Rothschild, Lynn; Schultz, Cynthia; Burgess, Seth; Skiles, J. W.

    2007-11-01

    A survey over two mountain slopes (Glaciar Martial and Cerro Guanaco) in the vicinity of Ushuaia (Tierra del Fuego, Argentina) showed normal results for the region in terms of chlorophyll concentration in the leaves of the dominant tree species Nothofagus antarctica, N. pumilio and N. betuloides, and soil variables such as temperature, moisture, pH, and concentration of nitrogen, sodium and potassium. Solar radiation, on the other hand, showed high values of ultraviolet over the 200-400 nm range, suggesting that the environment is extreme in terms of incoming solar radiation. The forest canopy absorbs and/or reflects a significant amount of that radiation. In separate analyses we showed that these tree species contain UV-absorbing pigments (cyanidin, delphidin, and flavonol glycosides). We submit that the rippled and glossy surface of leaves serves as a reflection/backscattering mechanism that protects their inner structure and function. The presence of krummholz (= twisted, dwarf trees) in the upper end of the forest shows the effects of an extreme environment.

  12. Intra and Inter-Population Morphological Variation of Shape and Size of the Chilean Magnificent Beetle, Ceroglossus chilensis in the Baker River Basin, Chilean Patagonia

    PubMed Central

    Benítez, Hugo A.; Briones, Raúl; Jerez, Viviane

    2011-01-01

    The alteration of habitat generates different degrees of stress in insects. It has been suggested that the degrees of phenotypic disturbances reflect the ability of an individual to overcome the effects of stress. The Baker River Basin in the Aysén Region, Chilean Patagonia has a very fragmented landscape, due to the destruction of the native forest and the use of land for agriculture and animal husbandry. This alteration should generate different degrees of disturbances in the insect communities, whose effects may be quantified by geometric morphometric tools. We analyzed morphological differences in 244 males and 133 females of the the Chilean magnificent beetle, Ceroglossus chilensis (Eschscholtz) (Coleoptera: Carabidae) collected in January, 2007, in mixed forests of Nothofagus dombeyi Mirbel (Ørsted) (Fagales: Nothofagaceae) and N. nitida Hofmus and in Second-growth forest of N. pumilio (Poepp. & Endl.) Krasser. Males were generally wider in the pronotum, while females had wider abdominal sternites. Although there were significant differences in shape and size between mature forests and second-growth forest, these were less significant among the sites within each type of vegetal formation. Individuals had more shape variations in the mature forest. We suggest that differences in shape are due at least in part to the isolation of the habitat. The differences found between sexes raises the question of how morphological variations and sexual dimorphism may be affected spatially by natural selection. PMID:21870986

  13. Assessment of land influence on a high-latitude marine coastal system: Tierra del Fuego, southernmost Argentina.

    PubMed

    Amin, Oscar; Comoglio, Laura; Spetter, Carla; Duarte, Claudia; Asteasuain, Raúl; Freije, Rubén Hugo; Marcovecchio, Jorge

    2011-04-01

    The study deals with the determination of physico-chemical parameters, inorganic nutrients, particulate organic matter, and photosynthetic pigments on a monthly basis during an annual cycle from nine sampling sites of the coastal zone of a high-latitude ecosystem (Tierra del Fuego, Argentina). Nitrites and phosphates concentrations were similar to other systems of the south Atlantic coast (median, 0.30 and 1.02 μM, respectively), while nitrates were higher in all sampling periods (median, 45.37 μM), and silicates were significantly smaller (median, 7.76 μM). Chlorophyll a and phaeopigments have shown median values of 0.38 and 0.85 mg m(-3), respectively, while saturated values of dissolved oxygen were recorded throughout the study. The analysis reflected that nutrient enrichment seems to be linked to an anthropogenic source, the presence of peatlands areas, and a sink of Nothofagus pumilio woods. The area could be characterized in three zones related to (1) high urban influence, (2) natural inputs of freshwater, and (3) mixed inputs coming from moderate urban impacts.

  14. Harold Varmus investido bajo juramento como 14.º director d

    Cancer.gov

    Ganador del Premio Nobel, doctor Harold E. Varmus, prestó juramento hoy como 14.º director del Instituto Nacional del Cáncer (NCI).  "Es muy estimulante que estés de regreso con nosotros", dijo la secretaria del Departamento de Salud y Servicios Humanos K

  15. Remote Sensing in Archeology: Classifying Bajos of the Paten, Guatemala

    NASA Technical Reports Server (NTRS)

    Lowry, James D., Jr.

    1998-01-01

    This project focuses on the adaptation of human populations to their environments from prehistoric times to the present. It emphasizes interdisciplinary research to develop ecological baselines through the use of remotely sensed imagery, in situ field work, and the modeling of human population dynamics. It utilizes cultural and biological data from dated archaeological sites to assess the subsistence and settlement patterns of human societies in response to changing climatic and environmental conditions. The utilization of remote sensing techniques in archaeology is relatively new, exciting, and opens many doors.

  16. In the right place at the right time: habitat representation in protected areas of South American Nothofagus-dominated plants after a dispersal constrained climate change scenario.

    PubMed

    Alarcón, Diego; Cavieres, Lohengrin A

    2015-01-01

    In order to assess the effects of climate change in temperate rainforest plants in southern South America in terms of habitat size, representation in protected areas, considering also if the expected impacts are similar for dominant trees and understory plant species, we used niche modeling constrained by species migration on 118 plant species, considering two groups of dominant trees and two groups of understory ferns. Representation in protected areas included Chilean national protected areas, private protected areas, and priority areas planned for future reserves, with two thresholds for minimum representation at the country level: 10% and 17%. With a 10% representation threshold, national protected areas currently represent only 50% of the assessed species. Private reserves are important since they increase up to 66% the species representation level. Besides, 97% of the evaluated species may achieve the minimum representation target only if the proposed priority areas were included. With the climate change scenario representation levels slightly increase to 53%, 69%, and 99%, respectively, to the categories previously mentioned. Thus, the current location of all the representation categories is useful for overcoming climate change by 2050. Climate change impacts on habitat size and representation of dominant trees in protected areas are not applicable to understory plants, highlighting the importance of assessing these effects with a larger number of species. Although climate change will modify the habitat size of plant species in South American temperate rainforests, it will have no significant impact in terms of the number of species adequately represented in Chile, where the implementation of the proposed reserves is vital to accomplish the present and future minimum representation. Our results also show the importance of using migration dispersal constraints to develop more realistic future habitat maps from climate change predictions.

  17. In the Right Place at the Right Time: Habitat Representation in Protected Areas of South American Nothofagus-Dominated Plants after a Dispersal Constrained Climate Change Scenario

    PubMed Central

    Alarcón, Diego; Cavieres, Lohengrin A.

    2015-01-01

    In order to assess the effects of climate change in temperate rainforest plants in southern South America in terms of habitat size, representation in protected areas, considering also if the expected impacts are similar for dominant trees and understory plant species, we used niche modeling constrained by species migration on 118 plant species, considering two groups of dominant trees and two groups of understory ferns. Representation in protected areas included Chilean national protected areas, private protected areas, and priority areas planned for future reserves, with two thresholds for minimum representation at the country level: 10% and 17%. With a 10% representation threshold, national protected areas currently represent only 50% of the assessed species. Private reserves are important since they increase up to 66% the species representation level. Besides, 97% of the evaluated species may achieve the minimum representation target only if the proposed priority areas were included. With the climate change scenario representation levels slightly increase to 53%, 69%, and 99%, respectively, to the categories previously mentioned. Thus, the current location of all the representation categories is useful for overcoming climate change by 2050. Climate change impacts on habitat size and representation of dominant trees in protected areas are not applicable to understory plants, highlighting the importance of assessing these effects with a larger number of species. Although climate change will modify the habitat size of plant species in South American temperate rainforests, it will have no significant impact in terms of the number of species adequately represented in Chile, where the implementation of the proposed reserves is vital to accomplish the present and future minimum representation. Our results also show the importance of using migration dispersal constraints to develop more realistic future habitat maps from climate change predictions. PMID:25786226

  18. Extreme defoliation reduces tree growth but not C and N storage in a winter-deciduous species

    PubMed Central

    Piper, Frida I.; Gundale, Michael J.; Fajardo, Alex

    2015-01-01

    Background and Aims There is a growing concern about how forests will respond to increased herbivory associated with climate change. Carbon (C) and nitrogen (N) limitation are hypothesized to cause decreasing growth after defoliation, and eventually mortality. This study examines the effects of a natural and massive defoliation by an insect on mature trees’ C and N storage, which have rarely been studied together, particularly in winter-deciduous species. Methods Survival, growth rate, carbon [C, as non-structural carbohydrate (NSC) concentration] and nitrogen (N) storage, defences (tannins and total polyphenols), and re-foliation traits were examined in naturally defoliated and non-defoliated adult trees of the winter-deciduous temperate species Nothofagus pumilio 1 and 2 years after a massive and complete defoliation caused by the caterpillar of Ormiscodes amphimone (Saturniidae) during summer 2009 in Patagonia. Key Results Defoliated trees did not die but grew significantly less than non-defoliated trees for at least 2 years after defoliation. One year after defoliation, defoliated trees had similar NSC and N concentrations in woody tissues, higher polyphenol concentrations and lower re-foliation than non-defoliated trees. In the second year, however, NSC concentrations in branches were significantly higher in defoliated trees while differences in polyphenols and re-foliation disappeared and decreased, respectively. Conclusions The significant reduction in growth following defoliation was not caused by insufficient C or N availability, as frequently assumed; instead, it was probably due to growth limitations due to factors other than C or N, or to preventative C allocation to storage. This study shows an integrative approach to evaluating plant growth limitations in response to disturbance, by examining major resources other than C (e.g. N), and other C sinks besides storage and growth (e.g. defences and re-foliation). PMID:25851136

  19. Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

    NASA Astrophysics Data System (ADS)

    Casteller, A.; Christen, M.; Villalba, R.; Martínez, H.; Stöckli, V.; Leiva, J. C.; Bartelt, P.

    2008-05-01

    The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1) to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2) to highlight the potential of textit{Nothofagus pumilio} tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

  20. Plant Responses to Increased UV-B Radiation: A Research Project

    NASA Technical Reports Server (NTRS)

    DAntoni, H. L.; Skiles, J. W.; Armstrong, R.; Coughlan, J.; Daleo, G.; Mayoral, A.; Lawless, James G. (Technical Monitor)

    1994-01-01

    because there is anecdotal evidence of plant damage on the saguaros that has been linked to increased UV radiation, and (3) the forests of Nothofagus spp. and the steppe of Patagonia where the risk of plant damage at 35S is 5% and increases to as much as 15% at 55S due to increased UV-B radiation. Measurements of UV-B radiation impinging on the surface at 55S largely exceed the predicted UV-B radiation values at 50 latitude and 0% ozone depletion. Preliminary HPLC analyses of UV-B absorbing compounds in Nothofagus antartica, N. pumilio, N. betuloides and Rumex sp. in natural conditions show species-specific patterns. The spectrum of N. antartica grown at 38S differs significantly from that of N. antartica in natural conditions in Ushuaia (55S). These results suggest that the selected main area (Patagonia) is appropriate for assessing the problem and its magnitude and that Nothofagus is appropriate for our study.

  1. Textos y gramatica del Pima Bajo (Texts and Grammar of the Lower Pima).

    ERIC Educational Resources Information Center

    Escalante, Roberto H.; Fernandez, Zarina Estrada

    This volume, entirely in Spanish and Pima, presents extensive descriptive information about the language spoken by the Pima of Mexico. An introductory chapter reviews the history of research on the language. The second and third chapters explain its phonology and morphology. In the fourth chapter, a number of oral histories and ethnographic texts…

  2. Ectomycorrhizal fungal communities coinvading with Pinaceae host plants in Argentina: Gringos bajo el bosque.

    PubMed

    Hayward, Jeremy; Horton, Thomas R; Nuñez, Martin A

    2015-10-01

    Coinvasive ectomycorrhizal (ECM) fungi allow Pinaceae species to invade regions otherwise lacking compatible symbionts, but ECM fungal communities permitting Pinaceae invasions are poorly understood. In the context of Pinaceae invasions on Isla Victoria, Nahuel Huapi National Park, Argentina, we asked: what ECM fungi are coinvading with Pinaceae hosts on Isla Victoria; are some ECM fungal species or genera more prone to invade than others; and are all ECM fungal species that associate with Northern Hemisphere hosts also nonnative, or are some native fungi compatible with nonnative plants? We sampled ECMs from 226 Pinaceae host plant individuals, both planted individuals and recruits, growing inside and invading from plantations. We used molecular techniques to examine ECM fungal communities associating with these trees. A distinctive subset of the ECM fungal community predominated far from plantations, indicating differences between highly invasive and less invasive ECM fungi. Some fungal invaders reported here have been detected in other locations around the world, suggesting strong invasion potential. Fungi that were frequently detected far from plantations are often found in early-successional sites in the native range, while fungi identified as late-successional species in the native range are rarely found far from plantations, suggesting a means for predicting potential fungal coinvaders. PMID:25963605

  3. Invarianza de las ecuaciones de movimiento bajo transformaciones de escala espacio-temporales en la dinamica de Newton modificada (MOND)

    NASA Astrophysics Data System (ADS)

    Acosta, R.; Tuiran, E.; Molina Redondo, U.

    2015-02-01

    The basic principles that originated the Modified Newtonian Dynamics MOND, are shown, as well as a description of the fundamentals aspects of the theory: modification of gravity and modification of inertia. Also, it is considered the behaviour of the movement equations under space-temporal scale transformations of the movement equations, that is, transformations that have the form (t, r) --> (lambda*t, r). It was observed in this way that the MOND regime comes from the requirement of the invariance of the movement equations with respect to this transformations.

  4. Migrant Education Programs Under ESEA Title I Migrant Amendment. (Programas de Educacion Migrante bajo el Titulo I de ESEA.)

    ERIC Educational Resources Information Center

    Minkler, Elton D.

    Migrant Education Programs are designed for those students who, because of the migratory nature of their parents' employment, are required to move from one school district to another during the school year. In many instances these students, because of sporadic attendance and discontinuity of their educational experiences, have found it difficult,…

  5. Resultado negativo de prueba del VPH es mejor predictor de riesgo bajo de cáncer de cuello uterino

    Cancer.gov

    De acuerdo con un estudio en el que participaron más de un millón de mujeres, los investigadores del NCI han determinado que el resultado negativo de una prueba para la detección del VPH proporciona mayor certeza o seguridad frente a riesgos futuros de cá

  6. Identity of two sympatric species of Orius (Heteroptera: Anthocoridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The two minute pirate bugs, Orius insidiosus (Say) (Heteroptera: Anthocoridae) and Orius pumilio (Champion) (Heteroptera: Anthocoridae), are closely related and sympatric in north Florida. Interspecific matings between the two species did not result in viable progeny. Although the morphological stru...

  7. Reconstructing streamflow variation of the Baker River from tree-rings in Northern Patagonia since 1765

    NASA Astrophysics Data System (ADS)

    Lara, Antonio; Bahamondez, Alejandra; González-Reyes, Alvaro; Muñoz, Ariel A.; Cuq, Emilio; Ruiz-Gómez, Carolina

    2015-10-01

    The understanding of the long-term variation of large rivers streamflow with a high economic and social relevance is necessary in order to improve the planning and management of water resources in different regions of the world. The Baker River has the highest mean discharge of those draining both slopes of the Andes South of 20°S and it is among the six rivers with the highest mean streamflow in the Pacific domain of South America (1100 m3 s-1 at its outlet). It drains an international basin of 29,000 km2 shared by Chile and Argentina and has a high ecologic and economic value including conservation, tourism, recreational fishing, and projected hydropower. This study reconstructs the austral summer - early fall (January-April) streamflow for the Baker River from Nothofagus pumilio tree-rings for the period 1765-2004. Summer streamflow represents 45.2% of the annual discharge. The regression model for the period (1961-2004) explains 54% of the variance of the Baker River streamflow (R2adj = 0.54). The most significant temporal pattern in the record is the sustained decline since the 1980s (τ = -0.633, p = 1.0144 ∗ 10-5 for the 1985-2004 period), which is unprecedented since 1765. The Correlation of the Baker streamflow with the November-April observed Southern Annular Mode (SAM) is significant (1961-2004, r = -0.55, p < 0.001). The Baker record is also correlated with the available SAM tree-ring reconstruction based on other species when both series are filtered with a 25-year spline and detrended (1765-2004, r = -0.41, p < 0.01), emphasizing SAM as the main climatic forcing of the Baker streamflow. Three of the five summers with the highest streamflow in the entire reconstructed record occurred after the 1950s (1977, 1958 and 1959). The causes of this high streamflow events are not yet clear and cannot be associated with the reported recent increase in the frequency of glacial-lake outburst floods (GLOFs). The decreasing trend in the observed and reconstructed

  8. Preguntas Y Respuestas, Programa para Ninos Migratorios Bajo el Titulo I de ESEA. 1971. (Questions and Answers, Program for Migrant Children Under ESEA Title I. 1971).

    ERIC Educational Resources Information Center

    Office of Education (DHEW), Washington, DC. Office of Programs for the Disadvantaged.

    Title I of the Elementary and Secondary Education Act of 1965 is specifically designed to help educationally deprived children. It was amended in 1966 to include the children of migratory agricultural workers. Today more than 235,000 migrant children receive educational and special supplementary services under Title I. Answers to some of the…

  9. Sistemas de Documentacion e Informacion Educativa en Belgica, Paises Bajos y Francia (Educational Documentation and Information Systems in Belgium, Holland, and France).

    ERIC Educational Resources Information Center

    Rossi Etchelouz, Nelly Yvis

    This booklet describes the working and organization of the information and documentation systems in Belgium, the Netherlands, and France. The discussion begins with a look at the Belgium educational system and how information services operate within that system. The central library, specialized services, and specialized information centers are all…

  10. Identity of Two Sympatric Species of Orius (Hemiptera: Heteroptera: Anthocoridae)

    PubMed Central

    Shapiro, Jeffrey P.; Shirk, Paul D.; Kelley, Karen; Lewis, Tamera M.; Horton, David R.

    2010-01-01

    The minute pirate bugs, Orius insidiosus (Say) and Orius pumilio (Champion) (Hemiptera: Heteroptera: Anthocoridae), are closely related species known to be sympatric in north Florida. Here, male and female genitalia, DNA sequences, and the effects of within- and between-species pairings on egg production and egg development were examined to develop a better understanding of the relationship between these two species. Interspecific matings between the two species did not result in viable progeny. Although there were gross similarities in the morphology of the male parameres (external genitalia) between the two species, the cone in O. pumilio was much broader with a greater spiral twist and the flagellum was longer than in O. insidiosus. Correspondingly, there were differences in the morphology of the copulatory tubes of the females of the two species. In O. insidiosus, the organ was somewhat longer than in O. pumilio and oriented parallel to the abdominal midline, while the copulatory tube in O. pumilio tilted slightly towards the midline. Additionally, the copulatory tube for O. pumilio included a sclerotized basal mound that was not present in O. insidiosus. These morphological differences suggest that successful copulation between these species could be difficult. In contrast to conspecific matings, interspecific matings resulted in few or no eggs laid over a period of two weeks and no viable progeny. Comparison of the 18S ribosomal gene ITS-1 sequences between the two species demonstrated only 91% homology. When yolk protein contents were examined to determine whether reproductive physiology had shifted to full egg production, interspecifically mated females contained amounts of yolk protein comparable to that in fed, but unmated females; this was less than 10% of the yolk protein previously found in fed and conspecifically mated females. These findings together confirm that O. insidiosus and O. pumilio are indeed two separate species. PMID:21265614

  11. Survey for zoonotic liver and intestinal trematode metacercariae in cultured and wild fish in An Giang Province, Vietnam

    PubMed Central

    Thu, Nguyen Diem; Dalsgaard, Anders; Loan, Ly Thi Thanh

    2007-01-01

    Although Vietnam has a high risk of fishborne zoonotic trematode (FZT) infections for humans, little information exists on the epidemiology of these infections in the country's fish. Because of the importance of cultured catfish and snakehead production in An Giang province, a major production area in the Mekong Delta of Vietnam, a survey for FZTs was carried out in randomly selected fish farms between June 2005 and March 2006. For comparison, wild fish from the same area were also surveyed. A total of 852 cultured fish from 4 districts were collected and examined by pepsin digestion to determine their FZT infection status. In Tra catfish, the prevalence of all types of metacercariae was 2.6%, of which the prevalence of Haplorchis pumilio was 0.7%. The overall prevalence of metacercariae in wild fish was 30.6%, of which 10.3% harbored zoonotic species: H. pumilio (2.8%) and Procerovum sp. (5.6%). The prevalence of Opisthorchis metacercariae, which were diagnosed as O. viverrini, was 1.9%. No metacercariae were found in cultured snakehead fish, although wild-caught snakehead fish had a FZT prevalence of 10.3%: 5.1% were O. viverrini; 2.6% H. pumilio; and 2.6% were Procerovum sp. These are the first reports of H. pumilio, Procerovum sp., and O. viverrini metacercariae in Vietnamese fish. These results indicate that consumption of improperly prepared fish represents a significant risk of acquiring FZTs in this south Vietnam region. PMID:17374978

  12. Efficacy of four traps in capturing male Helicoverpa moths in north Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two closely related species of Orius (Hemiptera:Anthocoridae) inhabit the Florida peninsula. While O. insidiosus is nearly ubiquitous east of the Rocky Mountains, O. pumilio is a tropical/subtropical species found in the U.S. no farther north than Alachua County. For two seasons we have observed p...

  13. Late-Holocene rodent middens from Rio Limay, Neuquen Province, Argentina

    USGS Publications Warehouse

    Markgraf, Vera; Betancourt, J.; Rylander, K.A.

    1997-01-01

    Pollen analysis of late-Holocene amberat deposits from two caves near the forest-steppe ecotone in northern Patagonia documents a major shift from Austrocedrus-Nothofagus forest to steppe shrub assemblages some time after 1800 and before 1300 BP. The probable explanation of the reduction of tree taxa calls for either drier summers or intensified land use or a combination of both.

  14. Collaborative Project Work Development in a Virtual Environment with Low-Intermediate Undergraduate Colombian Students (Desarrollo de trabajo colaborativo en un ambiente virtual con estudiantes colombianos de pregrado de nivel intermedio-bajo)

    ERIC Educational Resources Information Center

    Salinas Vacca, Yakelin

    2014-01-01

    This paper reports on an exploratory, descriptive, and interpretive study in which the roles of discussion boards, the students, the teacher, and the monitors were explored as they constructed a collaborative class project in a virtual environment. This research was conducted in the virtual program of a Colombian public university. Data were…

  15. Los Derechos de las Personas Incapacitadas Bajo la Ley Federal. Seccion 504 de la Ley de Rehabilitacion de 1973 (Handicapped Persons's Rights under Federal Law. Section 504 of the Rehabilitation Act of 1973).

    ERIC Educational Resources Information Center

    Office for Civil Rights (ED), Washington, DC.

    This Spanish-language pamphlet explains Section 504 of the Rehabilitation Act of 1973, which outlaws disability discrimination in programs receiving federal funds and the extensive regulations stemming from Section 504. The rights and responsibilities of handicapped persons are related to the following issues: eligibility for coverage under the…

  16. Visual mate choice in poison frogs.

    PubMed Central

    Summers, K; Symula, R; Clough, M; Cronin, T

    1999-01-01

    We investigated female mate choice on the basis of visual cues in two populations of Dendrobates pumilio, the strawberry poison frog, from the Bocas del Toro Archipelago in Panama, Central America. Mate choice experiments were carried out by presenting subject females of each of two morphs of this species (orange and green) from two different island populations (Nancy Key and Pope Island) with object frogs (one of each morph) under glass at one end of a terrarium. Recorded calls were played simultaneously from behind both object frogs. The experiments were carried out under two light regimes: (i) white light, and (ii) relatively monochromatic filtered blue light. Subject females from each population displayed a significant preference for their own morph under white light, but not under blue light. These results indicate that female D. pumilio use visual cues in mate choice, and suggest that colour may be the visual cue they use. PMID:10649631

  17. An example of the use of forensic palynology in assessing an alibi.

    PubMed

    Mildenhall, Dallas C

    2004-03-01

    A man was found shot in the back on Mount Holdsworth in the Tararua Ranges north of Wellington, the capital city of New Zealand. Police investigations pinpointed one individual who had been seen in the area, knew, and had the means and motive to kill the victim. His alibi was that an eyewitness was mistaken as he never had been in the area and the jacket he was reported to have been wearing had been purchased in The Netherlands and brought to Wellington, where it never had left the city. Furthermore the distinctive board shorts that he was reported to have been wearing had been purchased in a small coastal New Zealand town after the victim had been murdered. Pollen of Nothofagus menziesii, a mountain plant, on the clothing suggested that the alibi was untrue and that the clothing had been in mountains in the vicinity of Mount Holdsworth or a similar mountain scene where Nothofagus menziesii was growing.

  18. Rapid color evolution in an aposematic species: a phylogenetic analysis of color variation in the strikingly polymorphic strawberry poison-dart frog.

    PubMed

    Wang, Ian J; Shaffer, H Bradley

    2008-11-01

    Aposematism is one of the great mysteries of evolutionary biology. The evolution of aposematic coloration is poorly understood, but even less understood is the evolution of polymorphism in aposematic signals. Here, we use a phylogeographic approach to investigate the evolution of color polymorphism in Dendrobates pumilio, a well-known poison-dart frog (family Dendrobatidae), which displays perhaps the most striking color variation of any aposematic species. With over a dozen color morphs, ranging from bright red to dull green, D. pumilio provides an ideal opportunity to examine the evolution of color polymorphism and evolutionary shifts to cryptic coloration in an otherwise aposematic species. We constructed a phylogenetic tree for all D. pumilio color morphs from 3051bp of mtDNA sequence data, reconstructed ancestral states using parsimony and Bayesian methods, and tested the recovered tree against constraint trees using parametric bootstrapping to determine the number of changes to each color type. We find strong evidence for nearly maximal numbers of changes in all color traits, including five independent shifts to dull dorsal coloration. Our results indicate that shifts in coloration in aposematic species may occur more regularly than predicted and that convergence in coloration may indicate that similar forces are repeatedly driving these shifts. PMID:18764916

  19. Foodborne Trematode Metacercariae in Fish from Northern Vietnam and Their Adults Recovered from Experimental Hamsters

    PubMed Central

    Chai, Jong-Yil; De, Nguyen Van

    2012-01-01

    The prevalence of foodborne trematode (FBT) metacercariae was investigated in fish from 2 localities of northern Vietnam in 2004-2005. Freshwater fish (9 species) were collected from local markets in Hanoi City (n=76) and Nam Dinh Province (n=79), and were examined for FBT metacercariae using the artificial digestion technique. Adult flukes were obtained from hamsters experimentally infected with the metacercariae at day 8 post-infection. Three (Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium) and 6 (Haplorchis taichui, H. pumilio, C. formosanus, P. varium, Stellantchasmus falcatus, and Heterophyopsis continua) species of FBT metacercariae were detected in the 2 regions, respectively. Overall, among the positive fish species, H. pumilio metacercariae were detected in 104 (80.0%) of 130 fish examined (metacercarial density per infected fish; 64.2). C. formosanus metacercariae were found in 37 (40.2%) of 92 fish (metacercarial density; 14.7). P. varium metacercariae were detected in 19 (63.3%) of 30 fish (Anabas testudineus and Mugil cephalus) (metacercarial density; 247.7). S. falcatus metacercariae were found in all 10 M. cephalus examined (metacercarial density; 84.4). H. continua metacercariae (2 in number) were detected in 1 fish of Coilia lindmani. Morphologic characteristics of the FBT metacercariae and their experimentally obtained adults were described. The results have demonstrated that various FBT species are prevalent in northen parts of Vietnam. PMID:23230329

  20. Sexual dimorphism and directional sexual selection on aposematic signals in a poison frog

    PubMed Central

    Maan, Martine E.; Cummings, Molly E.

    2009-01-01

    It is commonly assumed that natural selection imposed by predators is the prevailing force driving the evolution of aposematic traits. Here, we demonstrate that aposematic signals are shaped by sexual selection as well. We evaluated sexual selection for coloration brightness in populations of the poison frog Oophaga [Dendrobates] pumilio in Panama's Bocas del Toro archipelago. We assessed female preferences for brighter males by manipulating the perceived brightness of spectrally matched males in two-way choice experiments. We found strong female preferences for bright males in two island populations and weaker or ambiguous preferences in females from mainland populations. Spectral reflectance measurements, coupled with an O. pumilio-specific visual processing model, showed that O. pumilio coloration was significantly brighter in island than in mainland morphs. In one of the island populations (Isla Solarte), males were significantly more brightly colored than females. Taken together, these results provide evidence for directional sexual selection on aposematic coloration and document sexual dimorphism in vertebrate warning coloration. Although aposematic signals have long been upheld as exemplars of natural selection, our results show that sexual selection should not be ignored in studies of aposematic evolution. PMID:19858491

  1. A new species of Acanthostigma (Tubeufiaceae, Dothideomycetes) from the southern hemisphere.

    PubMed

    Sánchez, R M; Miller, A N; Bianchinotti, M V

    2012-01-01

    A new species belonging to the Dothideomycete genus Acanthostigma is described from bark of two Nothofagus species from Argentina. Its identity as a new species is based on both morphology and molecular sequence data. Acanthostigma patagonica differs from other species in the genus by having larger ascomata and setae and wider, asymmetrical ascospores. An amended key to Acanthostigma species is provided along with a discussion of other species previously described from South America.

  2. Late-glacial and Holocene record of vegetation and climate from Cynthia Bay, Lake St Clair, Tasmania

    NASA Astrophysics Data System (ADS)

    Hopf, F. V. L.; Colhoun, E. A.; Barton, C. E.

    2000-10-01

    A Late-glacial-Holocene pollen record was obtained from a 3.96 m sediment core taken from Lake St Clair, central Tasmania. Modern vegetation and pollen analyses formed the basis for interpretation of the vegetation and climate history. Following deglaciation and before ca. 18450 yr BP Podocarpus lawrencei coniferous heath and Astelia-Plantago wet alpine herbfield became established at Lake St Clair. A distinct Poaceae-Plantago peak occurs between 18450 and 11210 yr BP and a mean annual temperature depression from ca. 6.2°C to 3°C below present is inferred for this period. The marked reduction in Podocarpus and strong increase of Poaceae suggests reduced precipitation levels during the period of widespread deglaciation (ca. 18.5-11 kyr BP). The local Late Pleistocene-Holocene non-forest to forest biostratigraphical boundary is dated at 11.2 kyr BP. It is characterised by expansion of the subalpine taxa Athrotaxis/Diselma with Nothofagus gunnii, and by the establishment of Nothofagus cunninghamii with Eucalyptus spp. A Phyllocladus bulge prior to the expansion of Nothofagus cunninghamii, reported at other Tasmanian sites, is not present at Lake St Clair. Nothofagus cunninghamii cool temperate rainforest peaked at 7800 yr BP, probably under wetter climatic conditions than present. The maximum development of rainforest in the early-middle Holocene may indicate that the temperature was slightly warmer than present, but the evidence is not definitive. The expansion of Eucalyptus spp. and Poaceae after 6000 yr BP may be partly a disclimax effect as a result of Aboriginal burning, but appears also to reflect reduced precipitation. The changes in vegetation and inferred climate can be explained by major changes in synoptic patterns of southern Australia and the adjacent southwest Pacific.

  3. New species of Tomentella (Thelephorales) from the Patagonian Andes forests.

    PubMed

    Kuhar, Francisco; Barroetaveña, Carolina; Rajchenberg, Mario

    2016-01-01

    The genus Tomentella forms abundant ectomycorrhizae in coniferous and deciduous forests worldwide. Molecular identification of root tips suggests undescribed species in the Nothofagus forests of Patagonia, Argentina. Tomentella tenuissima, T. pulvinulata and T. patagonica are described here as new to science based on morphological and molecular analyses. Their host range is addressed using available soil sequences. The identity of previous records of T. galzinii and T. radiosa are discussed with morphological and molecular evidence.

  4. New species of Tomentella (Thelephorales) from the Patagonian Andes forests.

    PubMed

    Kuhar, Francisco; Barroetaveña, Carolina; Rajchenberg, Mario

    2016-01-01

    The genus Tomentella forms abundant ectomycorrhizae in coniferous and deciduous forests worldwide. Molecular identification of root tips suggests undescribed species in the Nothofagus forests of Patagonia, Argentina. Tomentella tenuissima, T. pulvinulata and T. patagonica are described here as new to science based on morphological and molecular analyses. Their host range is addressed using available soil sequences. The identity of previous records of T. galzinii and T. radiosa are discussed with morphological and molecular evidence. PMID:27091385

  5. Prevalence of Haplorchis taichui among humans and fish in Luang Prabang Province, Lao PDR.

    PubMed

    Sohn, Woon-Mok; Yong, Tai-Soon; Eom, Keeseon S; Min, Duk-Young; Lee, Dongmin; Jung, Bong-Kwang; Banouvong, Virasack; Insisiengmay, Bounnaloth; Phommasack, Bounlay; Rim, Han-Jong; Chai, Jong-Yil

    2014-08-01

    This study confirmed the prevalence of the intestinal fluke Haplorchis taichui (Trematoda: Heterophyidae) among people and fish in Luang Prabang Province, Lao PDR. Fecal specimens were collected from 559 riparian people (229 males and 330 females), residing in 4 Districts (Luang Prabang, Xieng Ngeun, Pak Ou, and Nam Bak) and were examined by the Kato-Katz fecal smear technique. The overall helminth egg positive rate was 64.9%. The positive rate for small trematode eggs (STE), which may include H. taichui and other heterophyids, Opisthorchis viverrini, and lecithodendriids, was 15.2%. For recovery of adult helminths, 10 STE-positive people were treated with 40mg/kg praziquantel and 15mg/kg pyrantel pamoate, and then purged. Mixed infections with 3 Haplorchis species (H. taichui, H. pumilio, and H. yokogawai), a species of cestode (Taenia saginata), and several species of nematodes including Enterobius vermicularis and hookworms were found. The worm load for trematodes was exclusively high for H. taichui with an average of 7691 specimens per infected person, followed by H. yokogawai (8.3 specimens) and H. pumilio (4.1 specimens). Out of 207 freshwater fish (17 species) purchased in a market in Luang Prabang District, 138 (67%) harboured H. taichui metacercariae (metacercarial burden per fish; 520). Lower prevalence of fish and lower metacercarial density were observed for H. yokogawai (52% and 50 per fish, respectively) and H. pumilio (18% and 3 per fish, respectively). STE found in the surveyed population of Luang Prabang Province were verified to be those of intestinal fukes, particularly H. taichui. PMID:24754919

  6. Life cycle stages of heterophyid trematodes in Vietnamese freshwater fishes traced by molecular and morphometric methods.

    PubMed

    Skov, Jakob; Kania, Per W; Dalsgaard, Anders; Jørgensen, Thomas R; Buchmann, Kurt

    2009-03-01

    A survey of digenean zoonotic trematodes infecting snails and fishes in a North Vietnamese freshwater fish culture system revealed shedding of three types of parapleurolophocercous cercariae from the snail host Melanoides tuberculata and the presence of metacercariae within the genus Haplorchis (H. pumilio and H. taichui) and Procerovum sp. in tissues of cultured fishes (silver carp, Indian carp and climbing perch). No morphological characters were able to link the different cercariae specifically to any of the metacercariae. Subsequent molecular work including PCR and sequencing of ribosomal DNA (the ITS2 region) in cercariae and metacercariae associated only one type of the cercariae to the recovered H. pumilio metacercariae. Further, full identity (100%) was found with regard to the ITS sequence of adult H. pumilio obtained from the same North Vietnamese region. None of the cercariae showed sequence identities with H. taichui but more than 99% identity was found between one cercaria type and the Procerovum sp. metacercaria. It was indicated that trematode parasites of farmed fishes may originate from sources outside the fish ponds and may be introduced as free-swimming cercariae when pond water is being replenished by river water. Likewise, cercariae from the ponds may not always result in metacercarial infections of the farmed fishes. The present study frames the needs for including molecular techniques as auxiliary tools when conducting ecological studies of cercariae in complex ecosystems. The parasites recorded in the fish ponds are not only known to affect the health of aquacultured fishes but also the documented zoonotic potential of the diagnosed metacercaria calls for alerts regarding human consumption of raw or inadequately processed fish dishes. PMID:19056180

  7. The first African Anthracoptilidae (Insecta: Paoliida) near the Permian--Triassic boundary in Kenya.

    PubMed

    Nel, Andre; Garrouste, Romain; Prokop, Jakub

    2015-01-01

    The first findings of Antracoptilidae (Paoliida) from the Late Permian/ Early Triassic of Africa, i.e. the new genus Afrocladus comprising A. pumilio sp. nov. and A. kenyaensis sp. nov., are described from the Mombasa Basin of Maji ya Chumvi Formation in Kenya (Duruma sandstones). Both diagnoses are based on wing venation pattern. Their occurrences close to the P-T boundary possibly indicate the last appearence date of the group being known since early Pennsylvanian. Moreover, their significantly smaller wing sizes compared to known taxa suggest adaptations to different habitats and environmental conditions or different life strategy. PMID:25781736

  8. Holocene climate variability and environmental history at the Patagonian forest/steppe ecotone: Lago Mosquito (lat. 42.50°S, long. 71.40°W) and Laguna del Cóndor (lat. 42.20°S, long. 71.17°W)

    NASA Astrophysics Data System (ADS)

    Iglesias, V.; Whitlock, C. L.; Bianchi, M. M.

    2010-12-01

    Along the eastern Andes, a sharp ecotone separates steppe from North Patagonian forest dominated by Nothofagus spp. and Austrocedrus chilensis. The elevational position of the ecotone is determined by effective moisture, which in turn is governed by the strength and latitudinal position of the Southern Westerlies. As a result, past changes in ecotone position and composition, and fire activity provide an opportunity to examine past climate variations. Holocene environmental history at two sites in close proximity along a west-to-east moisture gradient is inferred from magnetic susceptibility, pollen and high-resolution charcoal data. Comparison of the two records enhanced the spatial resolution of the reconstruction. Pollen data suggest that, prior to 9 ka, vegetation resembled a modern steppe, in accordance with the widespread aridity characteristic of the period. Fires were infrequent, likely as a consequence of fuel discontinuity associated with low vegetation cover. At 9 ka, forest taxa expanded into the steppe. This change in community composition was reflected in the fire regime: fires became more frequent and biomass burning increased. This fire-vegetation linkage suggests that summers were arid enough to support fires but moisture was sufficient for Nothofagus forest to expand. Based on a westward displacement of the forest-steppe ecotone, drier-than-before conditions are inferred for the 5.5-3.7 ka period. A shift from crown to surface fires at the westernmost site, and lengthening fire return intervals towards the east accompanied this vegetation change. Between 3.7 and 2.4 ka, both sites registered an A. chilensis expansion, suggesting an increase in effective moisture. The last 2400 years are characterized by uninterrupted advances of Nothofagus forest. Ecotonal trees and shrubs, such as A. chilensis, Maytenus boaria and Rhamnaceae, have become less abundant, suggesting a recent trend towards cooler and/or wetter conditions.

  9. Genetic structure is correlated with phenotypic divergence rather than geographic isolation in the highly polymorphic strawberry poison-dart frog.

    PubMed

    Wang, Ian J; Summers, Kyle

    2010-02-01

    Phenotypic and genetic divergence can be influenced by a variety of factors, including sexual and natural selection, genetic drift and geographic isolation. Investigating the roles of these factors in natural systems can provide insight into the relative influences of allopatric and ecological modes of biological diversification in nature. The strawberry poison frog, Dendrobates pumilio, presents an excellent opportunity for this kind of research, displaying a diverse array of colour morphs and inhabiting a heterogeneous landscape that includes oceanic islands, fragmented rainforest patches and wide expanses of suitable habitat. In this study, we use 15 highly polymorphic microsatellite loci to estimate population structure and gene flow among populations from across the range of D. pumilio and a causal modelling framework to statistically test 12 hypotheses regarding the geographic and phenotypic variables that explain genetic differentiation within this system. Our results demonstrate that the genetic distance between populations is most strongly associated with differences in dorsal coloration. Previous experimental studies have shown that phenotypic differences can result in sexual and natural selection against non-native phenotypes, and our results now show that these forces lead to genetic isolation between different colour morphs in the wild, presenting a potential case of incipient speciation through selection. PMID:20025652

  10. Life history strategy influences parasite responses to habitat fragmentation.

    PubMed

    Froeschke, Götz; van der Mescht, Luther; McGeoch, Melodie; Matthee, Sonja

    2013-12-01

    Anthropogenic habitat use is a major threat to biodiversity and is known to increase the abundance of generalist host species such as rodents, which are regarded as potential disease carriers. Parasites have an intimate relationship with their host and the surrounding environment and it is expected that habitat fragmentation will affect parasite infestation levels. We investigated the effect of habitat fragmentation on the ecto- and endoparasitic burdens of a broad niche small mammal, Rhabdomys pumilio, in the Western Cape Province, South Africa. Our aim was to look at the effects of fragmentation on different parasite species with diverse life history characteristics and to determine whether general patterns can be found. Sampling took place within pristine lowland (Fynbos/Renosterveld) areas and at fragmented sites surrounded and isolated by agricultural activities. All arthropod ectoparasites and available gastrointestinal endoparasites were identified. We used conditional autoregressive models to investigate the effects of habitat fragmentation on parasite species richness and abundance of all recovered parasites. Host density and body size were larger in the fragments. Combined ecto- as well as combined endoparasite taxa showed higher parasite species richness in fragmented sites. Parasite abundance was generally higher in the case of R. pumilio individuals in fragmented habitats but it appears that parasites that are more permanently associated with the host's body and those that are host-specific show the opposite trend. Parasite life history is an important factor that needs to be considered when predicting the effects of habitat fragmentation on parasite and pathogen transmission.

  11. Nop9 is a PUF-like protein that prevents premature cleavage to correctly process pre-18S rRNA

    PubMed Central

    Zhang, Jun; McCann, Kathleen L.; Qiu, Chen; Gonzalez, Lauren E.; Baserga, Susan J.; Hall, Traci M. Tanaka

    2016-01-01

    Numerous factors direct eukaryotic ribosome biogenesis, and defects in a single ribosome assembly factor may be lethal or produce tissue-specific human ribosomopathies. Pre-ribosomal RNAs (pre-rRNAs) must be processed stepwise and at the correct subcellular locations to produce the mature rRNAs. Nop9 is a conserved small ribosomal subunit biogenesis factor, essential in yeast. Here we report a 2.1-Å crystal structure of Nop9 and a small-angle X-ray-scattering model of a Nop9:RNA complex that reveals a ‘C'-shaped fold formed from 11 Pumilio repeats. We show that Nop9 recognizes sequence and structural features of the 20S pre-rRNA near the cleavage site of the nuclease, Nob1. We further demonstrate that Nop9 inhibits Nob1 cleavage, the final processing step to produce mature small ribosomal subunit 18S rRNA. Together, our results suggest that Nop9 is critical for timely cleavage of the 20S pre-rRNA. Moreover, the Nop9 structure exemplifies a new class of Pumilio repeat proteins. PMID:27725644

  12. Only distance matters – non-choosy females in a poison frog population

    PubMed Central

    2013-01-01

    Background Females have often been shown to exhibit preferences for certain male traits. However, little is known about behavioural rules females use when searching for mates in their natural habitat. We investigated mate sampling tactics and related costs in the territorial strawberry poison frog (Oophaga pumilio) possessing a lek-like mating system, where both sequential and simultaneous sampling might occur. We continuously monitored the sampling pattern and behaviour of females during the complete period between two successive matings. Results We found no evidence that females compared males by visiting them. Instead females mated with the closest calling male irrespective of his acoustic and physical traits, and territory size. Playback experiments in the natural home ranges of receptive females revealed that tested females preferred the nearest speaker and did not discriminate between low and high call rates or dominant frequencies. Conclusions Our results suggest that females of O. pumilio prefer the closest calling male in the studied population. We hypothesize that the sampling tactic in this population is affected by 1) a strongly female biased sex ratio and 2) a low variance in traits of available males due to strong male-male competition, preventing low quality males from defending a territory and mating. PMID:23688371

  13. Fishborne Trematode Metacercariae in Freshwater Fish from Guangxi Zhuang Autonomous Region, China

    PubMed Central

    Eom, Keeseon S.; Min, Duk-Young; Rim, Han-Jong; Hoang, Eui-Hyug; Yang, Yichao; Li, Xueming

    2009-01-01

    A survey was performed to investigate the infection status of fishborne trematode (FBT) metacercariae in freshwater fish from Guangxi Zhuang Autonomous Region, China. A total of 307 freshwater fish of 31 species were collected from 5 administrative regions of Guangxi Zhuang Autonomous Region. They were examined by artificial digestion method from July 2003 to August 2004. No metacercariae were detected in fish from Fusui-xian. In fish from Mashan-xian and a market in Nanning, 3 species of metacercariae, Haplorchis taichui, Haplorchis pumilio, and Centrocestus formosanus, were mainly detected. Metacercariae (8 in number) of Clonorchis sinensis were found in 1 Chanodichthys dabryi purchased from a market in Nanning. In fish from Yangshuo, Metagonimus yokogawai metacercariae were detected from all 18 fish species examined. Total 13 C. sinensis metacercariae were found in 3 out of 10 Hemibarbus maculatus from Yangshuo. All 7 Zacco platypus from Yangshuo were infected with 8-112 Echinochasmus perfoliatus metacercariae. In fish from Binyang-xian, H. pumilo metacercariae were mainly detected in all 5 fish species examined, and only 1 metacercaria of C. sinensis was found in a Hemiculter leucisculus. From the above results, it was confirmed that some species of freshwater fish play a role of second intermediate hosts for FBT in Guangxi Zhuang Autonomous Region, China. In particular, 4 species of intestinal flukes, M. yokogawai, H. taichui, H. pumilio, and C. formosanus, were prevalent in fish hosts, whereas C. sinensis metacercariae were detected only in 3 fish species. PMID:19724698

  14. Late quaternary vegetation of southern Isla Grande de Chiloñ, Chile

    NASA Astrophysics Data System (ADS)

    Villagran, Carolina

    1988-05-01

    Late-glacial-Holocene forest history of southern Isla Chiloé (latitude 43°10' S) was reconstructed on the basis of pollen analysis in three profiles (Laguna Soledad, Laguna Chaiguata, Puerto Carmen). Prior to 12,500 yr B.P. pollen records are dominated by plant taxa characteristic of open habitats (Zone I). From 12,500 yr B.P. to the present, tree species predominate in the pollen records (Zones II-V). Between 12,500 and 9500 yr B.P. ombrophyllous taxa ( Nothofagus, Podocarpus nubigena. Myrtaceae, Fitzroya/Pilgerodendron, and Drimys) are frequent in all pollen diagrams, suggesting a wetter and colder climate than the present. Between 9000 and 5500 yr B.P. Valdivian forest elements, such as Nothofagus dombeyi type, Weinmannia, and Eucryphia/Caldcluvia, dominate, indicating a period of drier and warmer climate. From 5500 yr B.P. onward, the expansion of mixed North Patagonian-Subantarctic forest elements and the increased frequence of Tepualia suggest increased rainfall and temperatures oscillating around the modern values. The change from open to forest vegetation (ca. 12,500 yr B.P.) probably represents the most pronounced climatic change in the record and can be interpreted as the glacial-postglacial transition in the study area.

  15. Glacier fluctuations during the last 400 years at Mount San Lorenzo and Santa Ines Island, southern Chile

    NASA Astrophysics Data System (ADS)

    Aravena, J.; Luckman, B. H.

    2007-12-01

    We examine the local glacier fluctuations for the last 400 years in two mountain areas of the western coast of southernmost South America, Mount San Lorenzo and Santa Ines Island, using dendroglaciologic, geomorphologic and historical evidence. Mount San Lorenzo moraines span between 1636 and 1927 with periods of more frequent occurrence of glacial advances for the years 1670, 1770, 1870 and 1910. Santa Ines glacial advances are less numerous than in Mount San Lorenzo with well defined, clearly separated frontal moraines. The moraines were colonized by Nothofagus betuloides and Nothofagus antarctica two species with clear and well-preserved tree rings and the total age of the sampled trees was more precisely estimated. Dated moraines cover the last 300 years with evidence for advances during late 1600s, around 1800, 1860, 1910, 1930 and 1960. Further work is needed in dendroglaciological dating, geomorphologic surveying, and better understanding of local glacial dynamics for several glaciers to obtain a regional history of the glacier fluctuations of the southern Andes.

  16. Late Pleistocene Holocene environments in Valle Carbajal, Tierra del Fuego, Argentina

    NASA Astrophysics Data System (ADS)

    Borromei, Ana María; Coronato, Andrea; Quattrocchio, Mirta; Rabassa, Jorge; Grill, Silvia; Roig, Claudio

    2007-04-01

    The authors discuss Late Pleistocene-Holocene depositional environments in one of the Fuegian Andes valleys on the basis of palynological, geomorphological, and sedimentological analyses from two sites located near the Beagle Channel. The results obtained at these localities reinforce and refine the Late Pleistocene-Holocene climatic pattern previously recorded there. A colder period, associated with the Younger Dryas stadial event, is suggested by low Nothofagus pollen frequency, and communities of grass, low scrub, and shrub heath expanded into the low/middle slopes (10,310 14C yr BP). By ca. 9500 14C yr BP, warmer and drier conditions occurred, as evidenced by the development of open-grown vegetation in the valley floors (pollen zone O-3), followed by the expansion of open Nothofagus woodland (pollen zone O-2) in the middle Holocene. The milder climate subsequently changed, as indicated by the spreading of the closed forest and mire (pollen zone O-1), to more humid and cooler conditions during the last ca. 5000 yr BP.

  17. Hydro-Geomorphologic Effects Of Large Wood Jams On A Third-Order Stream (Tierra Del Fuego, Argentina)

    NASA Astrophysics Data System (ADS)

    Mao, L.; Andreoli, A.; Comiti, F.; Lenzi, M. A.; Iturraspe, R.; Burns, S.; Novillo, M. G.

    2007-05-01

    Dead wood pieces, especially when organized in jams, play an important geomorphic role in streams because of the effects on flow hydraulics, pool formation and sediments storage. The increase of stream morphological diversity and complexity also exerts also an important ecological role. This work reports on geomorphic role of large wood pieces and jams in a third order mountain stream located in the Southern Tierra del Fuego (Argentina), and draining an old-growth nothofagus forested basin not influenced by the beavers damming activity. Even if the in-stream number of wood pieces (length > 1m; diameter > 0.1 m) is comparable to what observed in other climatic areas, the slow growth of the nothofagus forest causes a lower wood abundance in terms of volumetric load. Since the relatively small dimensions of the surveyed large wood pieces, almost the 70% of them demonstrated to have been fluvial transported and the also wood jams reflect the apparent dynamic of wood in the channel. Wood jams exert a significant influence on the channel morphology, representing almost the half of the drop caused by steps and being responsible for the creation of 30% of the pools. The LW-forced pool volume is strongly and positively correlated to the height of the LW jam, and a significant inverse relationship between pool spacing and wood density within is evident if only the LW-forced pools are considered. The geomorphic influence of LW jams is also exerted by a considerable sediment storing capacity.

  18. Heavy metal and trace elements in riparian vegetation and macrophytes associated with lacustrine systems in Northern Patagonia Andean Range.

    PubMed

    Juárez, Andrea; Arribére, María A; Arcagni, Marina; Williams, Natalia; Rizzo, Andrea; Ribeiro Guevara, Sergio

    2016-09-01

    Vegetation associated with lacustrine systems in Northern Patagonia was studied for heavy metal and trace element contents, regarding their elemental contribution to these aquatic ecosystems. The research focused on native species and exotic vascular plant Salix spp. potential for absorbing heavy metals and trace elements. The native species studied were riparian Amomyrtus luma, Austrocedrus chilensis, Chusquea culeou, Desfontainia fulgens, Escallonia rubra, Gaultheria mucronata, Lomatia hirsuta, Luma apiculata, Maytenus boaria, Myrceugenia exsucca, Nothofagus antarctica, Nothofagus dombeyi, Schinus patagonicus, and Weinmannia trichosperma, and macrophytes Hydrocotyle chamaemorus, Isöetes chubutiana, Galium sp., Myriophyllum quitense, Nitella sp. (algae), Potamogeton linguatus, Ranunculus sp., and Schoenoplectus californicus. Fresh leaves were analyzed as well as leaves decomposing within the aquatic bodies, collected from lakes Futalaufquen and Rivadavia (Los Alerces National Park), and lakes Moreno and Nahuel Huapi (Nahuel Huapi National Park). The elements studied were heavy metals Ag, As, Cd, Hg, and U, major elements Ca, K, and Fe, and trace elements Ba, Br, Co, Cr, Cs, Hf, Na, Rb, Se, Sr, and Zn. Geochemical tracers La and Sm were also determined to evaluate contamination of the biological tissues by geological particulate (sediment, soil, dust) and to implement concentration corrections. PMID:27255321

  19. Derechos Educacionales de los Padres: Una Explicacion de los Procedimientos de Seguridad para los Padres de Ninos con Discapacidades. Bajo la Clausula del Acta de Educacion para Individuos con Discapacidades (IDEA) y las Reglas para la Administracion del Acta de Educacion para Ninos Excepcionales (Educational Rights of Parents: An Explanation of Procedural Safeguards Available to Parents of Children with Disabilities. Under Provisions of the Individuals with Disabilities Education Act (IDEA) and the Rules for the Administration of the Exceptional Children's Educational Act [ECEA]).

    ERIC Educational Resources Information Center

    Mountain Plains Regional Resource Center, Des Moines, IA.

    This pamphlet, in Spanish, describes Colorado parents' educational rights under federal and state special education rules and regulations. It addresses: (1) free appropriate public education and termination of services; (2) required prior notice to parents if there is a proposed change or refusal to change a child's special education program; (3)…

  20. An evaluation of the impacts of energy tree plantations on water resources in the United Kingdom under present and future UKCIP02 climate scenarios

    NASA Astrophysics Data System (ADS)

    Calder, Ian R.; Nisbet, Tom; Harrison, Jennifer A.

    2009-07-01

    The Hydrological Land Use Change model was used to assess the range of water resource impacts associated with four potential energy tree species (Eucalyptus nitens, Eucalyptus gunnii, Nothofagus sp., and Fraxinus excelsior) at eight United Kingdom locations under present and future, Environment Agency Rainfall and Weather Impacts Generator, climate scenarios generated using UK Climate Impacts Programme 2002 (UKCIP02). Parameter values were derived using expert opinion and interpolation because of limited data. For Fraxinus excelsior, there are questions concerning the unusual, in a world context, published findings that evaporation from a tree crop is less than that from grass. Model predictions indicated that under the present climate all tree species, excepting Fraxinus excelsior, at all sites have greater mean annual evaporation, (8 to 84%) and reduced water yields (-6 to -97%) compared with grass. The predicted increase in tree evaporation arises from parameter values reflecting both increased rainfall interception and higher transpiration due to deeper rooting depths. Under future climate scenarios, (1) "potential annual yield" (difference between actual rainfall and potential evaporation) will decrease, becoming negative at all studied sites in England and Wales by 2080; (2) at drier sites and for species with highest evaporation rates, E. nitens and Nothofagus, evaporation rates will decrease; (3) at wetter sites and for all species, evaporation rates will increase; (4) at all sites and for all species, water yields will decrease; (5) differences between species remain the same, with evaporation rates increasing and water yield decreasing in the order Fraxinus excelsior, grass, E. gunnii, Nothofagus, and E. Nitens; and (6) there is an overall trend through time toward convergence in water yields from trees and grass. If higher water yield predictions for Fraxinus excelsior are proved correct, this would represent an attractive land use option for water and

  1. Survival is linked with reaction time and spatial memory in African striped mice.

    PubMed

    Maille, Audrey; Schradin, Carsten

    2016-08-01

    Studying the association between fitness and cognition in free-living animals is a fundamental step in the elucidation of the evolution of cognition. We assessed whether survival until the onset of the breeding season was related to reaction time or spatial memory in the African striped mouse Rhabdomys pumilio, a rodent that has to survive summer drought before breeding. We tested a total of 90 individuals at the beginning of summer. Female survival was related to a faster response to predation stimuli. Male survival increased with greater spatial memory, possibly because it is important for males to remember the configuration of the environment during dispersal. This study revealed that individual variation in reaction time and spatial memory can be related to survival probability, which is important for understanding the selection pressures acting on basic cognitive traits. PMID:27484646

  2. Morpho-histological studies in the aromatic species of Chenopodium from Argentina.

    PubMed

    Bonzani, N E; Barboza, G E; Bugatti, M A; Ariza Espinar, L

    2003-04-01

    A morpho-histological study of the vegetative organs (stem and leaf) of the aromatic species of Chenopodium L. from Argentina [C. ambrosioides L., C. burkartii (Aellen) Vorosch., C. carinatum R. Br., C. chilense Schrad., C. graveolens Willd. var. bangii (Murr) Aellen, C. haumanii Ulbr., C. multifidum L., C. oblanceolatum (Speg.) Giusti, C. pumilio R. Br., C. retusum (Moq.) Moq., and C. venturii (Aellen) Cabrera] was carried out. Classifications for the glandular and non-glandular trichomes are established and their presence among species is presented. A variant in both the dorsiventral and isobilateral mesophyll is reported; some data are valuable for systematic purposes and for the identification of dried and smashed material used as vegetal drug.

  3. Translation and silencing in RNA granules: a tale of sand grains

    PubMed Central

    Pimentel, Jerónimo; Boccaccio, Graciela L.

    2014-01-01

    The transcriptome at the synapse consists of thousands of messengers encoding several cellular functions, including a significant number of receptors and ion channels and associated proteins. The concerted translational regulation of all these molecules contributes to the dynamic control of synaptic strength. Cumulative evidence supports that dendritic RNA granules and mRNA-silencing foci play an important role in translational regulation. Several relevant RBPs – FMRP; FUS/TLS; TDP-43; Staufen; Smaug; Pumilio; CPEB; HuD; ZBP1; and DDX6 among others – form granules that contain dormant mRNAs repressed by multiple pathways. Recent reports indicate that dendritic granules may contain stalled polysomes, and furthermore, active translation may occur in association with RNA granules. Here, we discuss the molecules and pathways involved in this continuum of RNA granules that contain masked mRNAs, mRNAs trapped in inactive polysomes or mRNAs engaged in translation. PMID:25100944

  4. Small mammals as hosts of immature ixodid ticks.

    PubMed

    Horak, I G; Fourie, L J; Braack, L E O

    2005-09-01

    Two hundred and twenty-five small mammals belonging to 16 species were examined for ticks in Free State, Mpumalanga and Limpopo Provinces, South Africa, and 18 ixodid tick species, of which two could only be identified to genus level, were recovered. Scrub hares, Lepus saxatilis, and Cape hares, Lepus capensis, harboured the largest number of tick species. In Free State Province Namaqua rock mice, Aethomys namaquensis, and four-striped grass mice, Rhabdomys pumilio, were good hosts of the immature stages of Haemaphysalis leachi and Rhipicephalus gertrudae, while in Mpumalanga and Limpopo Provinces red veld rats, Aethomys chrysophilus, Namaqua rock mice and Natal multimammate mice, Mastomys natalensis were good hosts of H. leachi and Rhipicephalus simus. Haemaphysalis leachi was the only tick recovered from animals in all three provinces.

  5. Toward a general approach for RNA-templated hierarchical assembly of split-proteins.

    PubMed

    Furman, Jennifer L; Badran, Ahmed H; Ajulo, Oluyomi; Porter, Jason R; Stains, Cliff I; Segal, David J; Ghosh, Indraneel

    2010-08-25

    The ability to conditionally turn on a signal or induce a function in the presence of a user-defined RNA target has potential applications in medicine and synthetic biology. Although sequence-specific pumilio repeat proteins can target a limited set of ssRNA sequences, there are no general methods for targeting ssRNA with designed proteins. As a first step toward RNA recognition, we utilized the RNA binding domain of argonaute, implicated in RNA interference, for specifically targeting generic 2-nucleotide, 3' overhangs of any dsRNA. We tested the reassembly of a split-luciferase enzyme guided by argonaute-mediated recognition of newly generated nucleotide overhangs when ssRNA is targeted by a designed complementary guide sequence. This approach was successful when argonaute was utilized in conjunction with a pumilio repeat and expanded the scope of potential ssRNA targets. However, targeting any desired ssRNA remained elusive as two argonaute domains provided minimal reassembled split-luciferase. We next designed and tested a second hierarchical assembly, wherein ssDNA guides are appended to DNA hairpins that serve as a scaffold for high affinity zinc fingers attached to split-luciferase. In the presence of a ssRNA target containing adjacent sequences complementary to the guides, the hairpins are brought into proximity, allowing for zinc finger binding and concomitant reassembly of the fragmented luciferase. The scope of this new approach was validated by specifically targeting RNA encoding VEGF, hDM2, and HER2. These approaches provide potentially general design paradigms for the conditional reassembly of fragmented proteins in the presence of any desired ssRNA target.

  6. Development of a PCR assay and pyrosequencing for identification of important human fish-borne trematodes and its potential use for detection in fecal specimens

    PubMed Central

    2014-01-01

    Background Small liver and minute intestinal flukes are highly prevalent in Southeast Asia. Definitive diagnosis of parasite infection is usually achieved parasitologically by finding the fluke eggs in feces. However, their eggs are difficult to differentiate morphologically in fecal samples, even for experienced technicians. The present study developed a PCR assay coupled with DNA pyrosequencing for identification of the fish-borne trematodes (FBT), Opisthorchis viverrini, Clonorchis sinensis, Haplorchis taichui, H. pumilio and Stellantchasmus falcatus, and to evaluate potential detection in fecal specimens, and identification and differentiation of cercarial and metacercarial stages. Methods Primers targeting the partial 28S large subunit ribosomal RNA gene were designed and about 46–47 nucleotides were selected as the target region for species identification by a PCR assay coupled with a pyrosequencing technique. Results The nucleotide variations at 24 positions, which is sufficient for the identification of the five species of FBT were selected. The method could identify O. viverrini and C. sinensis eggs in feces, cercarial and metacercarial stages of O. viverrini, and metacercarial stage of H. pumilio and H. taichui. The detection limit was as little as a single O. viverrini or C. sinensis egg artificially inoculated in 100 mg of non-infected fecal sample (equivalent to 10 eggs per gram), indicating highly sensitivity. The method was found to be superior to the traditional microscopy method and was more rapid than Sanger DNA sequencing. Conclusions DNA pyrosequencing-based identification is a valuable tool for differentiating O. viverrini and other Opisthorchis-like eggs, and can be applied to epidemiological studies and for molecular taxonomic investigation of FBT in endemic areas. PMID:24589167

  7. An Analysis of Predator Selection to Affect Aposematic Coloration in a Poison Frog Species.

    PubMed

    Dreher, Corinna E; Cummings, Molly E; Pröhl, Heike

    2015-01-01

    Natural selection is widely noted to drive divergence of phenotypic traits. Predation pressure can facilitate morphological divergence, for example the evolution of both cryptic and conspicuous coloration in animals. In this context Dendrobatid frogs have been used to study evolutionary forces inducing diversity in protective coloration. The polytypic strawberry poison frog (Oophaga pumilio) shows strong divergence in aposematic coloration among populations. To investigate whether predation pressure is important for color divergence among populations of O. pumilio we selected four mainland populations and two island populations from Costa Rica and Panama. Spectrometric measurements of body coloration were used to calculate color and brightness contrasts of frogs as an indicator of conspicuousness for the visual systems of several potential predators (avian, crab and snake) and a conspecific observer. Additionally, we conducted experiments using clay model frogs of different coloration to investigate whether the local coloration of frogs is better protected than non-local color morphs, and if predator communities vary among populations. Overall predation risk differed strongly among populations and interestingly was higher on the two island populations. Imprints on clay models indicated that birds are the main predators while attacks of other predators were rare. Furthermore, clay models of local coloration were equally likely to be attacked as those of non-local coloration. Overall conspicuousness (and brightness contrast) of local frogs was positively correlated with attack rates by birds across populations. Together with results from earlier studies we conclude that conspicuousness honestly indicates toxicity to avian predators. The different coloration patterns among populations of strawberry poison frogs in combination with behavior and toxicity might integrate into equally efficient anti-predator strategies depending on local predation and other ecological

  8. An Analysis of Predator Selection to Affect Aposematic Coloration in a Poison Frog Species.

    PubMed

    Dreher, Corinna E; Cummings, Molly E; Pröhl, Heike

    2015-01-01

    Natural selection is widely noted to drive divergence of phenotypic traits. Predation pressure can facilitate morphological divergence, for example the evolution of both cryptic and conspicuous coloration in animals. In this context Dendrobatid frogs have been used to study evolutionary forces inducing diversity in protective coloration. The polytypic strawberry poison frog (Oophaga pumilio) shows strong divergence in aposematic coloration among populations. To investigate whether predation pressure is important for color divergence among populations of O. pumilio we selected four mainland populations and two island populations from Costa Rica and Panama. Spectrometric measurements of body coloration were used to calculate color and brightness contrasts of frogs as an indicator of conspicuousness for the visual systems of several potential predators (avian, crab and snake) and a conspecific observer. Additionally, we conducted experiments using clay model frogs of different coloration to investigate whether the local coloration of frogs is better protected than non-local color morphs, and if predator communities vary among populations. Overall predation risk differed strongly among populations and interestingly was higher on the two island populations. Imprints on clay models indicated that birds are the main predators while attacks of other predators were rare. Furthermore, clay models of local coloration were equally likely to be attacked as those of non-local coloration. Overall conspicuousness (and brightness contrast) of local frogs was positively correlated with attack rates by birds across populations. Together with results from earlier studies we conclude that conspicuousness honestly indicates toxicity to avian predators. The different coloration patterns among populations of strawberry poison frogs in combination with behavior and toxicity might integrate into equally efficient anti-predator strategies depending on local predation and other ecological

  9. An Analysis of Predator Selection to Affect Aposematic Coloration in a Poison Frog Species

    PubMed Central

    Dreher, Corinna E.; Cummings, Molly E.; Pröhl, Heike

    2015-01-01

    Natural selection is widely noted to drive divergence of phenotypic traits. Predation pressure can facilitate morphological divergence, for example the evolution of both cryptic and conspicuous coloration in animals. In this context Dendrobatid frogs have been used to study evolutionary forces inducing diversity in protective coloration. The polytypic strawberry poison frog (Oophaga pumilio) shows strong divergence in aposematic coloration among populations. To investigate whether predation pressure is important for color divergence among populations of O. pumilio we selected four mainland populations and two island populations from Costa Rica and Panama. Spectrometric measurements of body coloration were used to calculate color and brightness contrasts of frogs as an indicator of conspicuousness for the visual systems of several potential predators (avian, crab and snake) and a conspecific observer. Additionally, we conducted experiments using clay model frogs of different coloration to investigate whether the local coloration of frogs is better protected than non-local color morphs, and if predator communities vary among populations. Overall predation risk differed strongly among populations and interestingly was higher on the two island populations. Imprints on clay models indicated that birds are the main predators while attacks of other predators were rare. Furthermore, clay models of local coloration were equally likely to be attacked as those of non-local coloration. Overall conspicuousness (and brightness contrast) of local frogs was positively correlated with attack rates by birds across populations. Together with results from earlier studies we conclude that conspicuousness honestly indicates toxicity to avian predators. The different coloration patterns among populations of strawberry poison frogs in combination with behavior and toxicity might integrate into equally efficient anti-predator strategies depending on local predation and other ecological

  10. Hyperendemicity of Haplorchis taichui infection among riparian people in Saravane and Champasak province, Lao PDR.

    PubMed

    Chai, Jong-Yil; Yong, Tai-Soon; Eom, Keeseon S; Min, Duk-Young; Jeon, Hyeong-Kyu; Kim, Tae-Yun; Jung, Bong-Kwang; Sisabath, Lay; Insisiengmay, Bounnaloth; Phommasack, Bounlay; Rim, Han-Jong

    2013-06-01

    In this study, we found that Haplorchis taichui, a heterophyid intestinal fluke, is highly prevalent, with heavy worm loads, among riparian people in Saravane and Champasak province, Lao PDR. Fecal specimens were collected from 1,460 people (717 men and 743 women) in 12 riparian (Mekong river) districts and were examined by the Kato-Katz fecal smear technique. The overall helminth egg positive rate was 78.8% and 66.4% in Saravane and Champasak province, respectively. The positive rate for small trematode eggs (STE), which included H. taichui and other heterophyids, Opisthorchis viverrini, and lecithodendriids, was 69.9% and 46.3% in Saravane and Champasak province, respectively. To obtain adult flukes, 30 STE-positive people were treated with 40 mg/kg praziquantel and then purged. Whole diarrheic stools were collected 4-5 times for each person and searched for fluke specimens using a stereomicroscope. Mixed infections with various species of trematodes (H. taichui, Haplorchis pumilio, O. viverrini, Prosthodendrium molenkampi, Centrocestus formosanus, and Echinochasmus japonicus) and a species of cestode (Taenia saginata) were found. However, the worm load was exceptionally high for H. taichui compared with other trematode species, with an average of 21,565 and 12,079 specimens per infected person in Saravane and Champasak province, respectively, followed by H. pumilio (41.9 and 22.5, respectively) and O. viverrini (9.4 and 1.5, respectively). These results show that diverse species of intestinal and liver flukes are prevalent among riparian people in Saravane and Champasak province, Lao PDR, with H. taichui being the exceptionally dominant species. PMID:23864741

  11. A new species of Alsodes (Anura: Alsodidae) from Altos de Cantillana, central Chile.

    PubMed

    Charrier, Andrés; Correa, Claudio; Castro, Camila; Méndez, Marco A

    2015-01-01

    Based on morphological and molecular evidence (mitochondrial and nuclear sequences) we describe a new species of spiny-chest frog, Alsodes cantillanensis, from central Chile (around 34°S). The type locality, Quebrada Infiernillo, is located in the Coastal Range at approximately 65 km from Santiago (Metropolitan Region), the capital of Chile. The distribution of the new species is included entirely in that of A. nodosus (32-36°S approximately), which was identified as the sister taxon according to molecular phylogenetic analyses. Moreover, both species are sympatric in the type locality. The new species was found in a Nothofagus macrocarpa relict forest potentially threatened by gold mining activities. We identify other threats for its conservation and some biological data needed for understanding the evolution of this species. This discovery reveals the scarce knowledge about biogeography, evolution and ecology of spiny-chest frogs from central Chile. 

  12. Lignin analysis by FT-Raman spectroscopy

    SciTech Connect

    Agarwal, U.P.; Obst, J.R.; Cannon, A.B.

    1996-10-01

    Traditional methods of lignin analysis, such as Klason (acid insoluble) lignin determinations, give satisfactory results, are widely accepted, and often are considered as standard analyses. However, the Klason lignin method is laborious and time consuming; it also requires a fairly large-amount of isolated analyte. FT-Raman spectroscopy offers an opportunity to simplify and speed up lignin analyses. FT-Raman data for a number of hardwoods (angiosperms) and softwoods (gymnosperms) are compared with data obtained using other analytical methods, including Klason lignin (with corrections for acid soluble lignin), acetyl bromide, and FT-IR determinations. In addition, 10 different specimens of Nothofagus dombeyii (chosen because of the widely varying syringyl:guaiacyl monomer compositions of their lignins) were also analyzed. Lignin monomer compositions were determined by thioacidolysis of by nitrobenzene oxidation.

  13. First Evidence for Wollemi Pine-type Pollen (Dilwynites: Araucariaceae) in South America

    PubMed Central

    Macphail, Mike; Carpenter, Raymond J.; Iglesias, Ari; Wilf, Peter

    2013-01-01

    We report the first fossil pollen from South America of the lineage that includes the recently discovered, extremely rare Australian Wollemi Pine, Wollemia nobilis (Araucariaceae). The grains are from the late Paleocene to early middle Eocene Ligorio Márquez Formation of Santa Cruz, Patagonia, Argentina, and are assigned to Dilwynites, the fossil pollen type that closely resembles the pollen of modern Wollemia and some species of its Australasian sister genus, Agathis. Dilwynites was formerly known only from Australia, New Zealand, and East Antarctica. The Patagonian Dilwynites occurs with several taxa of Podocarpaceae and a diverse range of cryptogams and angiosperms, but not Nothofagus. The fossils greatly extend the known geographic range of Dilwynites and provide important new evidence for the Antarctic region as an early Paleogene portal for biotic interchange between Australasia and South America. PMID:23894439

  14. A new species of Rhytidognathus (Carabidae, Migadopini) from Argentina

    PubMed Central

    Roig-Juñent, Sergio; Rouaux, Julia

    2012-01-01

    Abstract The Migadopini are a small tribe of Carabidae with 47 species that occur in South America, Australia, and New Zealand, in the sub-Antarctic areas. In South America, most of the genera inhabit areas related to sub-Antartic Nothofagus forest except two monogeneric genera, the Ecuadorian genus Aquilex Moret and the Pampean genus Rhytidognathus Chaudoir. These two genera are geographically isolated from the remaining five South American genera. New material of Rhytidognathus from the northeast of Buenos Aires province and from Entre Ríos province permits establishing that the previous records of Rhytidognathus ovalis (Dejean) for Argentina were erroneous and that it belongs to a new species. Based on external morphological characters and from male and female genitalia we describe Rhytidognathus platensis as a new species. In this contribution we provide illustrations, keys, habitat characteristics and some biogeographic considerations on the distribution of Rhytidognathus. PMID:23275755

  15. First evidence for Wollemi Pine-type pollen (Dilwynites: Araucariaceae) in South America.

    PubMed

    Macphail, Mike; Carpenter, Raymond J; Iglesias, Ari; Wilf, Peter

    2013-01-01

    We report the first fossil pollen from South America of the lineage that includes the recently discovered, extremely rare Australian Wollemi Pine, Wollemia nobilis (Araucariaceae). The grains are from the late Paleocene to early middle Eocene Ligorio Márquez Formation of Santa Cruz, Patagonia, Argentina, and are assigned to Dilwynites, the fossil pollen type that closely resembles the pollen of modern Wollemia and some species of its Australasian sister genus, Agathis. Dilwynites was formerly known only from Australia, New Zealand, and East Antarctica. The Patagonian Dilwynites occurs with several taxa of Podocarpaceae and a diverse range of cryptogams and angiosperms, but not Nothofagus. The fossils greatly extend the known geographic range of Dilwynites and provide important new evidence for the Antarctic region as an early Paleogene portal for biotic interchange between Australasia and South America. PMID:23894439

  16. Philodryas chamissonis (Reptilia: Squamata: Colubridae) preys on the arboreal marsupial Dromiciops gliroides (Mammalia: Microbiotheria: Microbiotheriidae).

    PubMed

    Muñoz-Leal, S; Ardiles, K; Figueroa, R A; González-Acuña, D

    2013-02-01

    Philodryas chamissonis, the Chilean long-tailed snake, is a diurnal predator mainly of Liolaemus lizards, but also of amphibians, birds, rodents and juvenile rabbits. Dromiciops gliroides (Colocolo opossum) is an arboreal marsupial endemic of temperate rainforest of southern South America. Little information is available about this marsupial's biology and ecology. Here we report the predation of one Colocolo opossum by an adult female P. chamissonis in a mixed Nothofagus forest, composed mainly by N. dombeyi, N. glauca and N. alpina trees, in the "Huemules de Niblinto" National Reserve, Nevados de Chillán, Chile. Since these two species have different activity and habitat use patterns, we discuss how this encounter may have occurred. Although it could just have been an opportunistic event, this finding provides insights into the different components of food chains in forest ecosystems of Chile.

  17. Coevolution and the adaptive value of autumn tree colours: colour preference and growth rates of a southern beech aphid.

    PubMed

    Ramírez, C C; Lavandero, B; Archetti, M

    2008-01-01

    The evolutionary explanation for the change in leaf colour during autumn is still debated. Autumn colours could be a signal of defensive commitment towards insects (coevolution) or an adaptation against physical damage because of light at low temperatures (photoprotection). These two hypotheses have different predictions: (1) under the coevolution hypothesis, insects should not prefer red leaves in autumn and grow better in spring on trees with green autumn leaves; and (2) under the photoprotection hypothesis, insects should prefer and grow better on trees with red leaves because they provide better nutrition. Studying colour preference in autumn and growth rates in spring of a southern beech aphid species (Neuquenaphis staryi) on Nothofagus alessandrii, we found preference for green leaves in autumn but no differential performance of aphids in spring. We suggest that aphid preference for green might have evolved to exploit better their host during the autumn rather than to improve their performance in spring.

  18. Vegetation, Fire and Climate Over the Last 2000 Yrs in Central West Patagonia (45°S)

    NASA Astrophysics Data System (ADS)

    Villa-Martinez, R. P.; Simi, E. I.; Moreno, P. I.

    2014-12-01

    We report high-resolution pollen and charcoal records from lake sediments obtained from Lago Mellizas and Lago Churrasco to reconstruct the history of vegetation, fire and past variations of the southern westerly winds (SWW) over the last 2000 years. Both sites are located near to the climate-modulated forest-steppe ecotone in central west Patagonia. In this region the SWW are the only source of precipitation and is ideal for reconstructing past changes in atmospheric circulation. This is facilitated by the marked west-east precipitation gradient across the Patagonian Andes that induces a zonation of the regional vegetation which can be used for inferring past changes in precipitation regimes based on fossil pollen records. Furthermore, the Chilean-European colonization process in central west Patagonia started early in the 20th century, allowing characterization of natural vegetation and climate variability in the absence of human disturbance until the end of the 19th century. The pollen records shows dominance of Nothofagus deciduous forests with minor fluctuations and low herb and aquatics abundances, which suggest humid climate conditions. We detect a major change in the pollen stratigraphy at 200 cal yr BP, when started a sustained decreasing trend in Nothofagus, along with increases of Poaceae and aquatics plants (Cyperaceae, Myriophyllum). We interpret these changes as a forest opening and centripetal expansion of littoral environments toward the lake center driven by lake-level lowering in response to lowered precipitation brought by the SWW. Pinus, Rumex, Plantago, which indicate human perturbation, increase in 1900 AD. Macroscopic charcoal increases at 1750, 1400, 850-700, 500, and 200 cal yr BP, suggesting local fires, followed by sharp increases during the last 100 years. We interpret the pre-20th century charcoal peaks as dry intervals with lowered SWW influence. Acknowledgement: Fondecyt 1121141, Fondap 15110009, and ICM grants P02-51 and NC120066.

  19. 78 FR 65972 - Caribbean Fishery Management Council; Scoping Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ..., Bajo de Sico, and Tourmaline Bank. The goal of modifying the closures is to protect the red hind... achieve a more natural sex ratio, age, and size structure, while minimizing adverse social and...

  20. 78 FR 15356 - Caribbean Fishery Management Council; Public Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-11

    ... Sierra-Tourmaline off the West Coast of Puerto Rico--Graciela Garc a-Moliner/Bill Arnold --Shared Jurisdictions: Bajo de Sico and Tourmaline --Seasonal Area Closures Differences in Months SEFSC Queen...

  1. Climate-vegetation-fire linkages on decadal-to-millennial time scales along the Patagonian forest-steppe ecotone (41 - 43°S)

    NASA Astrophysics Data System (ADS)

    Iglesias, V.; Whitlock, C. L.

    2013-12-01

    Patagonian vegetation has dramatically changed in composition and distribution over the last 16,000 years. Although patterns of vegetation change are relatively clear, our understanding of the processes that produce them is limited. In this study, we reconstructed the vegetation and fire history of the North Patagonian forest-steppe ecotone (41 - 43°S) and linked past ecological changes to variations in large-scale synoptic controls of climate and past human activity. Postglacial vegetation and fire dynamics were inferred from high-resolution pollen and charcoal records from seven lakes located along the forest-steppe ecotone in the eastern flanks of the Andes. We fit Mixed Generalized Additive Models to these time series to estimate regional trends in vegetation composition and biomass burning through time, and compared them with independent paleoclimate data so as to assess long-term vegetation-fire-climate linkages. Pollen data indicate that late-glacial steppe was replaced by open forest in the early Holocene and by closed forest in the middle and late Holocene. Fire activity was lowest during the late-glacial to early-Holocene transition and gradually increased through the Holocene. Long-term vegetation and fire patterns responded to variations in seasonal and annual insolation and their effect on moisture during the growing season. Submillennial-scale precipitation variability explained much of the fine-scale ecotonal behavior, mainly through its effect on fire, which can amplify or override the direct influence of climate on ecotone composition. During the late Holocene, in particular, century-long oscillations in forest composition were largely driven by changes in humidity, associated with the strengthening of the westerlies and ENSO variability. Humid periods (4900-3800 cal yr BP, 2850-1350 cal yr BP) promoted Nothofagus forest, and dry times (3800-2850 cal yr BP, 1350-450 cal yr BP) favored Austrocedrus expansion. At intermediate moisture levels

  2. Miocene Antarctic Terrestrial Realm

    NASA Astrophysics Data System (ADS)

    Ashworth, A. C.; Lewis, A.; Marchant, D. R.

    2009-12-01

    The discovery of several locations in the Transantarctic Mountains that contain macrofossils and pollen is transforming our understanding of late Cenozoic Antarctica. The most southerly location is on the Beardmore Glacier (85.1°S) about 500 km from the South Pole. The environment was an active glacial margin in which plants, insects and freshwater mollusks inhabited the sand and gravel bars and small lakes on an outwash plain. In addition to leaves and wood of dwarf Nothofagus (Southern Beech) shrubs, achenes of Ranunculus (Buttercup), in situ cushion growth forms of mosses and a vascular plant, the assemblages contains various exoskeletal parts of carabid and curculionid beetles and a cyclorrhaphan fly, the shells of freshwater bivalve and gastropod species and a fish tooth. Initially the deposits were assigned a Pliocene age (3.5 Ma) but a mid- to early Miocene age is more probable (c. 14 - 25 Ma) based on correlation of fossil pollen from the deposits with 39Ar/40Ar dated pollen assemblages from the McMurdo Dry Valleys locations. The oldest location within the Dry Valleys also involved an active ice margin but was part of a valley system that was completely deglaciated for intervals long enough for thick paleosols to develop. The Friis Hills fossil deposits of the Taylor Valley region (77.8°S) are at least 19.76 Ma based on the 39Ar/40Ar age of a volcanic ash bed. The valley floor during the non-glacial phases had poorly-drained soils and the extensive development of mossy mires. Wood and leaves of Nothofagus are abundant in lacustrine deposits. The silts of shallow fluvial channels contain abundant megaspores and spiky leaves of the aquatic lycopod Isoetes (Quillwort). Fossils of beetles are also present in these deposits. During the glacial phases, proglacial lakes were surrounded by dwarfed, deciduous Nothofagus shrubs. The youngest fossils recovered from the Dry Valleys are from the Olympus Range (77.5°S) with an age of 14.07 Ma. The environment was an

  3. The early to mid-Miocene environment of Antarctica

    NASA Astrophysics Data System (ADS)

    Ashworth, A. C.; Lewis, A.

    2012-12-01

    Paleoecological studies in the Transantarctic Mountains of the McMurdo region provide evidence that the climate was both warmer and wetter in the early to mid-Miocene than it was during the late Miocene. The climate change was accompanied by a shift from wet- to cold-based glaciation in the TAM and the probable growth of the polar ice sheet. Terrestrial and freshwater aquatic fossil assemblages from the Friis Hills (77°S) and the Olympus Range (77°S), with endpoint 40Ar/39Ar ages on tephras of 19.76 Ma and 14.07 Ma, respectively, indicate climatic cooling during the interval. At c.14 Ma, the temperature dropped below the threshold required to support the plants and insects of a tundra biome, and they became extinct. This interpretation is supported by pollen studies from Ross Sea cores. The extinction of the tundra biota on the continent appears to have been time-transgressive, occurring at 12.8 Ma on the Antarctic Peninsula. Evidence of climatic cooling from early to mid-Miocene is based on a decrease in biodiversity. During interglacial phases of the early Miocene, the poorly drained valley of the Friis Hills supported a sexually-reproducing moss community dominated by Campylium cf. polygamum, which today grows on the margins of lakes and in soil between boulders. Wood and leaves of Nothofagus (Southern Beech), and the seeds of at least five other angiosperm species are preserved as fossils. In addition, there are abundant megaspores and spiny, curved leaves of the aquatic lycopod Isoetes (Quillwort), as well as chitinous remains of curculionid beetles and Chironomidae (midges). During glacial phases, the only fossils found are Nothofagus leaves of a species which appears to be different than that associated with the interglacial phases. Pollen supports the interpretation that there was more than one species of Nothofagus in the vegetation. The types and numbers of species indicate that the vegetation was a shrub tundra. The closest modern analog for the fossil

  4. The vegetation cover of New Zealand at the Last Glacial Maximum

    NASA Astrophysics Data System (ADS)

    Newnham, Rewi; McGlone, Matt; Moar, Neville; Wilmshurst, Janet; Vandergoes, Marcus

    2013-08-01

    A new reconstruction of the vegetation cover for New Zealand at the Last Glacial Maximum (LGM) is presented, based primarily on a database of 66 pollen site records and a more limited range of plant macrofossil and coleopteran records. Extensive forest is evident only from Auckland northwards. Conifer-broadleaf forest similar to that in the region today, but with Agathis australis scarce, persisted in the far north, whilst Nothofagus trees and a range of shrub taxa characterised the more open forests elsewhere in Northland. Survival of Nothofagus-dominated forest in coastal and exposed continental shelf locations to the southwest of Auckland and northwestern South Island is also indicated. Beyond these regions, vegetation cover comprised shrubland- and grassland-dominant communities, with the latter more prominent in eastern areas, to the south and presumably at higher altitudes. Nevertheless the survival of forest trees is indicated unambiguously in most regions apart from the eastern South Island. Thus the concept of 'micro glacial forest refugia' in New Zealand remains supported by this latest glacial vegetation reconstruction and we draw possible parallels with the developing but contentious concept of 'northern cryptic refugia' in Europe. Recent assertions that pollen and beetle reconstructions of the New Zealand LGM vegetation patterns diverge significantly are not supported by this analysis. Rather, the two proxies are readily reconciled if the term 'woody' as indicated by coleoptera is not restricted to tall forest trees but extended to the widespread woody shrub and small tree elements of the New Zealand flora. Regional distinctions in the LGM vegetation reconstruction concur broadly with the contemporary vegetation pattern, suggesting that, along with temperature depression and likely drier growing conditions, a zonal circulation regime with prominent southern westerly winds was important at 21 ka, as it is today. Pollen-climate modelling of the extent of

  5. Environmental changes in two lakes of Northern Patagonia (Chile): A 1000 yr reconstruction based on pollen and charcoal

    NASA Astrophysics Data System (ADS)

    Nicole, Vargas; Laura, Torres; Alberto, Araneda; Fabiola, Cruces; Fernando, Torrejón; Denisse, Alvarez; G, Bizama; Nathalie, Fagel; Roberto, Urrutia

    2010-05-01

    We aim to reconstruct the environmental changes experimented in Patagonian ecosystems during the last 1000 years. We analyze sediment cores from two lakes (Thompson and Burgos), located in Aysen Region, Southern Chile. The samples were obtained using a gravity corer and sampled at intervals of 1 cm to 30 cm depth and every 5 cm until the end of the core. Thompson lake sediment core was sampled every 5 cm. Age model is based on radiocarbon datings on bulk sediments and macroremains. In Burgos lake we evidence two main climatic changes. A wet period between 876-1444 AD is marked by the presence of Pteridophytes. A colder and dryer period is then evidenced by an increase of Berberis sp between 1444 and 1656 AD. From 1834 AD to Present the sediment record is mainly affected by human activities. High concentrations of carbon particles and a sharp change in pollen assemblage (increase of Poaceae, decrease of Nothofagus dombeyi-Type) are indicators of two large fire events. The lacustrine sediment of Thompson is characterized by a wetter period, between 874 - 1168 AD, with abundance of Pteridophytes. Then from 1168 AD to Present the environmental conditions of the watershed were characterized by lower ferns and fire events. Two major fires were evidenced between 1850 AD and Present. Like in Burgos they are marked by major changes in plant associations (sharp increase in Poaceae, drastic loss of Nothofagus dombeyi-Type). Wet periods identified in both lakes at the base of the sediment record could correspond to manifestations of a warm climate anomaly like the Medieval Warm Period. The dry and cold period, especially obvious in the Burgos record, could be associated to a cold climate anomaly. Finally the great changes in vegetation that occurred from the year ~ 1830 in the basin of the two lakes were directly related to human activities (forest cutting) developed during the ninetheenth and twentieth centuries. This research is funded by both Chilean and Belgian projects

  6. CLIPZ: a database and analysis environment for experimentally determined binding sites of RNA-binding proteins.

    PubMed

    Khorshid, Mohsen; Rodak, Christoph; Zavolan, Mihaela

    2011-01-01

    The stability, localization and translation rate of mRNAs are regulated by a multitude of RNA-binding proteins (RBPs) that find their targets directly or with the help of guide RNAs. Among the experimental methods for mapping RBP binding sites, cross-linking and immunoprecipitation (CLIP) coupled with deep sequencing provides transcriptome-wide coverage as well as high resolution. However, partly due to their vast volume, the data that were so far generated in CLIP experiments have not been put in a form that enables fast and interactive exploration of binding sites. To address this need, we have developed the CLIPZ database and analysis environment. Binding site data for RBPs such as Argonaute 1-4, Insulin-like growth factor II mRNA-binding protein 1-3, TNRC6 proteins A-C, Pumilio 2, Quaking and Polypyrimidine tract binding protein can be visualized at the level of the genome and of individual transcripts. Individual users can upload their own sequence data sets while being able to limit the access to these data to specific users, and analyses of the public and private data sets can be performed interactively. CLIPZ, available at http://www.clipz.unibas.ch, aims to provide an open access repository of information for post-transcriptional regulatory elements.

  7. CLIPZ: a database and analysis environment for experimentally determined binding sites of RNA-binding proteins

    PubMed Central

    Khorshid, Mohsen; Rodak, Christoph; Zavolan, Mihaela

    2011-01-01

    The stability, localization and translation rate of mRNAs are regulated by a multitude of RNA-binding proteins (RBPs) that find their targets directly or with the help of guide RNAs. Among the experimental methods for mapping RBP binding sites, cross-linking and immunoprecipitation (CLIP) coupled with deep sequencing provides transcriptome-wide coverage as well as high resolution. However, partly due to their vast volume, the data that were so far generated in CLIP experiments have not been put in a form that enables fast and interactive exploration of binding sites. To address this need, we have developed the CLIPZ database and analysis environment. Binding site data for RBPs such as Argonaute 1-4, Insulin-like growth factor II mRNA-binding protein 1-3, TNRC6 proteins A-C, Pumilio 2, Quaking and Polypyrimidine tract binding protein can be visualized at the level of the genome and of individual transcripts. Individual users can upload their own sequence data sets while being able to limit the access to these data to specific users, and analyses of the public and private data sets can be performed interactively. CLIPZ, available at http://www.clipz.unibas.ch, aims to provide an open access repository of information for post-transcriptional regulatory elements. PMID:21087992

  8. A universal strategy for regulating mRNA translation in prokaryotic and eukaryotic cells

    PubMed Central

    Cao, Jicong; Arha, Manish; Sudrik, Chaitanya; Mukherjee, Abhirup; Wu, Xia; Kane, Ravi S.

    2015-01-01

    We describe a simple strategy to control mRNA translation in both prokaryotic and eukaryotic cells which relies on a unique protein–RNA interaction. Specifically, we used the Pumilio/FBF (PUF) protein to repress translation by binding in between the ribosome binding site (RBS) and the start codon (in Escherichia coli), or by binding to the 5′ untranslated region of target mRNAs (in mammalian cells). The design principle is straightforward, the extent of translational repression can be tuned and the regulator is genetically encoded, enabling the construction of artificial signal cascades. We demonstrate that this approach can also be used to regulate polycistronic mRNAs; such regulation has rarely been achieved in previous reports. Since the regulator used in this study is a modular RNA-binding protein, which can be engineered to target different 8-nucleotide RNA sequences, our strategy could be used in the future to target endogenous mRNAs for regulating metabolic flows and signaling pathways in both prokaryotic and eukaryotic cells. PMID:25845589

  9. Assortative mating in poison-dart frogs based on an ecologically important trait.

    PubMed

    Reynolds, R Graham; Fitzpatrick, Benjamin M

    2007-09-01

    The origin of new species can be influenced by both deterministic and stochastic factors. Mate choice and natural selection may be important deterministic causes of speciation (as opposed to the essentially stochastic factors of geographic isolation and genetic drift). Theoretical models predict that speciation is more likely when mate choice depends on an ecologically important trait that is subject to divergent natural selection, although many authors have considered such mating/ecology pleiotropy, or "magic-traits" to be unlikely. However, phenotypic signals are important in both mate choice and ecological processes such as avoiding predation. In chemically defended species, it may be that the phenotypic characteristics influencing mate choice are the same signals being used to transmit a warning to potential predators, although few studies have demonstrated this in wild populations. We tested for assortative mating between two color morphs of the Strawberry Poison-Dart Frog, Dendrobates pumilio, a group with striking geographic variation in aposematic color patterns. We found that females significantly prefer individuals of their own morph under two different light treatments, indicating strong assortative mating based on multiple coloration cues that are also important ecological signals. This study provides a rare example of one phenotypic trait affecting both ecological viability and nonrandom mating, indicating that mating/ecology pleiotropy is plausible in wild populations, particularly for organisms that are aposematically colored and visually orienting. PMID:17767594

  10. Fragment-based modelling of single stranded RNA bound to RNA recognition motif containing proteins

    PubMed Central

    de Beauchene, Isaure Chauvot; de Vries, Sjoerd J.; Zacharias, Martin

    2016-01-01

    Protein-RNA complexes are important for many biological processes. However, structural modeling of such complexes is hampered by the high flexibility of RNA. Particularly challenging is the docking of single-stranded RNA (ssRNA). We have developed a fragment-based approach to model the structure of ssRNA bound to a protein, based on only the protein structure, the RNA sequence and conserved contacts. The conformational diversity of each RNA fragment is sampled by an exhaustive library of trinucleotides extracted from all known experimental protein–RNA complexes. The method was applied to ssRNA with up to 12 nucleotides which bind to dimers of the RNA recognition motifs (RRMs), a highly abundant eukaryotic RNA-binding domain. The fragment based docking allows a precise de novo atomic modeling of protein-bound ssRNA chains. On a benchmark of seven experimental ssRNA–RRM complexes, near-native models (with a mean heavy-atom deviation of <3 Å from experiment) were generated for six out of seven bound RNA chains, and even more precise models (deviation < 2 Å) were obtained for five out of seven cases, a significant improvement compared to the state of the art. The method is not restricted to RRMs but was also successfully applied to Pumilio RNA binding proteins. PMID:27131381

  11. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Museum für Naturkunde, Berlin

    PubMed Central

    Breure, Abraham S.H.

    2013-01-01

    Abstract The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Zebra quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = Orthalicus bensoni (Reeve, 1849); Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789); Porphyrobaphe (Myiorthalicus) dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848); Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909); Orthalicus (Laeorthalicus) reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821); Bulimus (Eurytus) corticosus Sowerby III, 1895 = Plekocheilus (Eurytus) stuebeli Martens, 1885. The taxon Bulimus (Eudioptus) psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007) and a partial list of letters present in the correspondence archives. PMID:23794831

  12. Structural basis for specific recognition of multiple mRNA targets by a PUF regulatory protein

    SciTech Connect

    Wang, Yeming; Opperman, Laura; Wickens, Marvin; Tanaka Hall, Traci M.

    2011-11-02

    Caenorhabditis elegans fem-3 binding factor (FBF) is a founding member of the PUMILIO/FBF (PUF) family of mRNA regulatory proteins. It regulates multiple mRNAs critical for stem cell maintenance and germline development. Here, we report crystal structures of FBF in complex with 6 different 9-nt RNA sequences, including elements from 4 natural mRNAs. These structures reveal that FBF binds to conserved bases at positions 1-3 and 7-8. The key specificity determinant of FBF vs. other PUF proteins lies in positions 4-6. In FBF/RNA complexes, these bases stack directly with one another and turn away from the RNA-binding surface. A short region of FBF is sufficient to impart its unique specificity and lies directly opposite the flipped bases. We suggest that this region imposes a flattened curvature on the protein; hence, the requirement for the additional nucleotide. The principles of FBF/RNA recognition suggest a general mechanism by which PUF proteins recognize distinct families of RNAs yet exploit very nearly identical atomic contacts in doing so.

  13. Community structure of fleas within and among populations of three closely related rodent hosts: nestedness and beta-diversity.

    PubMed

    VAN DER Mescht, Luther; Krasnov, Boris R; Matthee, Conrad A; Matthee, Sonja

    2016-09-01

    We studied nestedness and its relationships with beta-diversity in flea communities harboured by three closely related rodent species (Rhabdomys pumilio, Rhabdomys intermedius, Rhabdomys dilectus) at two spatial scales (within and among host populations) in South Africa and asked (a) whether variation in species composition of flea communities within and among host populations follows a non-random pattern; if yes, (b) what are the contributions of nestedness and species turnover to dissimilarity (= beta-diversity) among flea communities at the two scales; and (c) do the degree of nestedness and its contribution to beta-diversity differ among host species (social vs solitary) and between scales. We found that nestedness in flea assemblages was more pronounced (a) in social than solitary host species and (b) at lower (among host individuals within populations) than at higher scale (among host populations). We also found that higher degree of nestedness was associated with its higher contribution to beta-diversity. Our findings support earlier ideas that parasite community structure results from the processes of parasite accumulation by hosts rather than from the processes acting within parasite communities.

  14. UIS2: A Unique Phosphatase Required for the Development of Plasmodium Liver Stages

    PubMed Central

    Zhang, Min; Mishra, Satish; Sakthivel, Ramanavelan; Fontoura, Beatriz M. A.; Nussenzweig, Victor

    2016-01-01

    Plasmodium salivary sporozoites are the infectious form of the malaria parasite and are dormant inside salivary glands of Anopheles mosquitoes. During dormancy, protein translation is inhibited by the kinase UIS1 that phosphorylates serine 59 in the eukaryotic initiation factor 2α (eIF2α). De-phosphorylation of eIF2α-P is required for the transformation of sporozoites into the liver stage. In mammalian cells, the de-phosphorylation of eIF2α-P is mediated by the protein phosphatase 1 (PP1). Using a series of genetically knockout parasites we showed that in malaria sporozoites, contrary to mammalian cells, the eIF2α-P phosphatase is a member of the PP2C/PPM phosphatase family termed UIS2. We found that eIF2α was highly phosphorylated in uis2 conditional knockout sporozoites. These mutant sporozoites maintained the crescent shape after delivery into mammalian host and lost their infectivity. Both uis1 and uis2 were highly transcribed in the salivary gland sporozoites but uis2 expression was inhibited by the Pumilio protein Puf2. The repression of uis2 expression was alleviated when sporozoites developed into liver stage. While most eukaryotic phosphatases interact transiently with their substrates, UIS2 stably bound to phosphorylated eIF2α, raising the possibility that high-throughput searches may identify chemicals that disrupt this interaction and prevent malaria infection. PMID:26735921

  15. Heat production in cold and long scotophase acclimated and winter acclimatized rodents

    NASA Astrophysics Data System (ADS)

    Haim, A.; Fourie, F. Le R.

    1980-09-01

    Heat production by means of oxygen consumptionVo2 (at Ta = 6° C, 25° C, 30° C, and 32° C) and non-shivering thermogenesis (NST) were studied in individuals of a diurnal rodent ( Rhabdomys pumilio) and a nocturnal rodent ( Praomys natalensis). The studied mice were acclimated to cold at Ta=8°C with a photoperiod of LD 12:12. On the otherhand specimens of these two species were acclimated at Ta=25°C with a long scotophase LD8:16. The results were compared with a control group (Ta=25° C, LD 12:12) and winter acclimatized individuals of both species.Vo2 in cold acclimated mice of both species was significantly increased when compared to the control group and was even higher than the winter acclimatized group when measured below the lower critical temperature. Long scotophase acclimated mice of both species also increased their oxygen consumption significantly when compared to the control group. NST was significantly increased in long scotophase acclimated mice from both species when compared to the control group. The results of this study indicate that the effects of acclimation to long scotophase are similar to those of cold acclimation. As changes in photoperiod are regular, it may be assumed that heat production mechanisms in acclimatization to winter will respond to changes in photoperiodicity.

  16. Post-transcriptional gene expression control by NANOS is up-regulated and functionally important in pRb-deficient cells.

    PubMed

    Miles, Wayne O; Korenjak, Michael; Griffiths, Lyra M; Dyer, Michael A; Provero, Paolo; Dyson, Nicholas J

    2014-10-01

    Inactivation of the retinoblastoma tumor suppressor (pRb) is a common oncogenic event that alters the expression of genes important for cell cycle progression, senescence, and apoptosis. However, in many contexts, the properties of pRb-deficient cells are similar to wild-type cells suggesting there may be processes that counterbalance the transcriptional changes associated with pRb inactivation. Therefore, we have looked for sets of evolutionary conserved, functionally related genes that are direct targets of pRb/E2F proteins. We show that the expression of NANOS, a key facilitator of the Pumilio (PUM) post-transcriptional repressor complex, is directly repressed by pRb/E2F in flies and humans. In both species, NANOS expression increases following inactivation of pRb/RBF1 and becomes important for tissue homeostasis. By analyzing datasets from normal retinal tissue and pRb-null retinoblastomas, we find a strong enrichment for putative PUM substrates among genes de-regulated in tumors. These include pro-apoptotic genes that are transcriptionally down-regulated upon pRb loss, and we characterize two such candidates, MAP2K3 and MAP3K1, as direct PUM substrates. Our data suggest that NANOS increases in importance in pRb-deficient cells and helps to maintain homeostasis by repressing the translation of transcripts containing PUM Regulatory Elements (PRE).

  17. MeCP2 suppresses nuclear microRNA processing and dendritic growth by regulating the DGCR8/Drosha complex.

    PubMed

    Cheng, Tian-Lin; Wang, Zhizhi; Liao, Qiuming; Zhu, Ying; Zhou, Wen-Hao; Xu, Wenqing; Qiu, Zilong

    2014-03-10

    Loss- and gain-of-function mutations of the X-linked gene MECP2 (methyl-CpG binding protein 2) lead to severe neurodevelopmental disorders in humans, such as Rett syndrome (RTT) and autism. MeCP2 is previously known as a transcriptional repressor by binding to methylated DNA and recruiting histone deacetylase complex (HDAC). Here, we report that MeCP2 regulates gene expression posttranscriptionally by suppressing nuclear microRNA processing. We found that MeCP2 binds directly to DiGeorge syndrome critical region 8 (DGCR8), a critical component of the nuclear microRNA-processing machinery, and interferes with the assembly of Drosha and DGCR8 complex. Protein targets of MeCP2-suppressed microRNAs include CREB, LIMK1, and Pumilio2, which play critical roles in neural development. Gain of function of MeCP2 strongly inhibits dendritic and spine growth, which depends on the interaction of MeCP2 and DGCR8. Thus, control of microRNA processing via direct interaction with DGCR8 represents a mechanism for MeCP2 regulation of gene expression and neural development.

  18. A multitasking Argonaute: exploring the many facets of C. elegans CSR-1.

    PubMed

    Wedeles, Christopher J; Wu, Monica Z; Claycomb, Julie M

    2013-12-01

    While initial studies of small RNA-mediated gene regulatory pathways focused on the cytoplasmic functions of such pathways, identifying roles for Argonaute/small RNA pathways in modulating chromatin and organizing the genome has become a topic of intense research in recent years. Nuclear regulatory mechanisms for Argonaute/small RNA pathways appear to be widespread, in organisms ranging from plants to fission yeast, Caenorhabditis elegans to humans. As the effectors of small RNA-mediated gene regulatory pathways, Argonaute proteins guide the chromatin-directed activities of these pathways. Of particular interest is the C. elegans Argonaute, chromosome segregation and RNAi deficient (CSR-1), which has been implicated in such diverse functions as organizing the holocentromeres of worm chromosomes, modulating germline chromatin, protecting the genome from foreign nucleic acid, regulating histone levels, executing RNAi, and inhibiting translation in conjunction with Pumilio proteins. CSR-1 interacts with small RNAs known as 22G-RNAs, which have complementarity to 25 % of the protein coding genes. This peculiar Argonaute is the only essential C. elegans Argonaute out of 24 family members in total. Here, we summarize the current understanding of CSR-1 functions in the worm, with emphasis on the chromatin-directed activities of this ever-intriguing Argonaute.

  19. Posterior elongation in the annelid Platynereis dumerilii involves stem cells molecularly related to primordial germ cells.

    PubMed

    Gazave, Eve; Béhague, Julien; Laplane, Lucie; Guillou, Aurélien; Préau, Laetitia; Demilly, Adrien; Balavoine, Guillaume; Vervoort, Michel

    2013-10-01

    Like most bilaterian animals, the annelid Platynereis dumerilii generates the majority of its body axis in an anterior to posterior temporal progression with new segments added sequentially. This process relies on a posterior subterminal proliferative body region, known as the "segment addition zone" (SAZ). We explored some of the molecular and cellular aspects of posterior elongation in Platynereis, in particular to test the hypothesis that the SAZ contains a specific set of stem cells dedicated to posterior elongation. We cloned and characterized the developmental expression patterns of orthologs of 17 genes known to be involved in the formation, behavior, or maintenance of stem cells in other metazoan models. These genes encode RNA-binding proteins (e.g., tudor, musashi, pumilio) or transcription factors (e.g., myc, id, runx) widely conserved in eumetazoans. Most of these genes are expressed both in the migrating primordial germ cells and in overlapping ring-like patterns in the SAZ, similar to some previously analyzed genes (piwi, vasa). The SAZ patterns are coincident with the expression of proliferation markers cyclin B and PCNA. EdU pulse and chase experiments suggest that new segments are produced through many rounds of divisions from small populations of teloblast-like posterior stem cells. The shared molecular signature between primordial germ cells and posterior stem cells in Platynereis thus corresponds to an ancestral "stemness" program. PMID:23891818

  20. Climate-Induced Range Shifts and Possible Hybridisation Consequences in Insects

    PubMed Central

    Sánchez-Guillén, Rosa Ana; Muñoz, Jesús; Rodríguez-Tapia, Gerardo; Feria Arroyo, T. Patricia; Córdoba-Aguilar, Alex

    2013-01-01

    Many ectotherms have altered their geographic ranges in response to rising global temperatures. Current range shifts will likely increase the sympatry and hybridisation between recently diverged species. Here we predict future sympatric distributions and risk of hybridisation in seven Mediterranean ischnurid damselfly species (I. elegans, I. fountaineae, I. genei, I. graellsii, I. pumilio, I. saharensis and I. senegalensis). We used a maximum entropy modelling technique to predict future potential distribution under four different Global Circulation Models and a realistic emissions scenario of climate change. We carried out a comprehensive data compilation of reproductive isolation (habitat, temporal, sexual, mechanical and gametic) between the seven studied species. Combining the potential distribution and data of reproductive isolation at different instances (habitat, temporal, sexual, mechanical and gametic), we infer the risk of hybridisation in these insects. Our findings showed that all but I. graellsii will decrease in distributional extent and all species except I. senegalensis are predicted to have northern range shifts. Models of potential distribution predicted an increase of the likely overlapping ranges for 12 species combinations, out of a total of 42 combinations, 10 of which currently overlap. Moreover, the lack of complete reproductive isolation and the patterns of hybridisation detected between closely related ischnurids, could lead to local extinctions of native species if the hybrids or the introgressed colonising species become more successful. PMID:24260411

  1. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Museum für Naturkunde, Berlin.

    PubMed

    Breure, Abraham S H

    2013-01-01

    The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Zebra quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = Orthalicus bensoni (Reeve, 1849); Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789); Porphyrobaphe (Myiorthalicus) dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848); Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909); Orthalicus (Laeorthalicus) reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821); Bulimus (Eurytus) corticosus Sowerby III, 1895 = Plekocheilus (Eurytus) stuebeli Martens, 1885. The taxon Bulimus (Eudioptus) psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007) and a partial list of letters present in the correspondence archives. PMID:23794831

  2. PREVALENCE OF TREMATODE LARVAE IN INTERMEDIATE HOSTS: SNAILS AND FISH IN KO AE SUB-DISTRICT OF KHUEANG NAI, UBON RATCHATHANI PROVINCE, THAILAND.

    PubMed

    Sripa, Jittiyawadee; Kiatsopit, Nadda; Piratae, Supawadee

    2016-05-01

    Ko Ae Sub-district of Khueang Nai, Ubon Ratchathani Province, Thailand is located in an endemic area for Opisthorchis viverrini and other fish-borne zoonotic trematodes (FZT) infection. This study shows the status in Ko Ae Sub-district of FZT infection based on availability of intermediate hosts and necessary requirements for the transmission of FZT. A cross-sectional survey of intermediate hosts of FZT, including Bithynia siamensis goniomphalos and cyprinoid fish, was conducted from April 2013 to December 2014. Examination of 1,000 snails revealed 3.4% were infected with trematode cercariae, with a density of infection greater than 100 cercariae per infected snail. Six groups of morphologically-distinguishable trematode cercariae were identified, namely, cystophorous, echinostome, furcocercous, mutabile, parapleurolophocercous, and xiphidio, the latter being the most predominant type. Among 250 cyprinoid fish samples with metacercariae present at their caudal fins and examined for FZT by pepsin digestion, metacer- cariae of Haplorchis taichui, H. pumilio, and Centrocestus formosanus were found. Unidentified metacercariae collected from fish caudal fins were subsequently shown using a PCR-based assay to be C. formosanus. No infection by O. viverrini in the intermediate hosts, Bithynia siamensis goniomphalos and cyprinoid fish was evident. The study provides new information regarding trematode larvae infection in the primary and secondary intermediate hosts of FZT in this area of Thailand.

  3. Bioactive alkaloids of frog skin: Combinatorial bioprospecting reveals that pumiliotoxins have an arthropod source

    PubMed Central

    Daly, John W.; Kaneko, Tetsuo; Wilham, Jason; Garraffo, H. Martin; Spande, Thomas F.; Espinosa, Alex; Donnelly, Maureen A.

    2002-01-01

    Nearly 500 alkaloids have been detected in skin extracts from frogs of the family Dendrobatidae. All seem to have been sequestered unchanged into skin glands from alkaloid-containing arthropods. Ants, beetles, and millipedes seem to be the source of decahydroquinolines, certain izidines, coccinellines, and spiropyrrolizidine oximes. But the dietary source for a major group of frog-skin alkaloids, namely the pumiliotoxins (PTXs), alloPTXs, and homoPTXs, remained a mystery. In hopes of revealing an arthropod source for the PTX group, small arthropods were collected from eight different sites on a Panamanian island, where the dendrobatid frog (Dendrobates pumilio) was known to contain high levels of two PTXs. The mixed arthropod collections from several sites, each representing up to 20 arthropod taxa, contained PTX 307A and/or alloPTX 323B. In addition, the mixed arthropod collections from several sites contained a 5,8-disubstituted indolizidine (205A or 235B), representing another class of alkaloids previously unknown from an arthropod. An ant alkaloid, decahydroquinoline 195A, was detected in the mixed arthropod collections from several sites. Thus, “combinatorial bioprospecting” demonstrates that further collection and analysis of individual taxa of leaf-litter arthropods should reveal the taxa from which PTXs, alloPTXs, and 5,8-disubstituted indolizidines are derived. PMID:12381780

  4. Migration of germline progenitor cells is directed by sphingosine-1-phosphate signalling in a basal chordate.

    PubMed

    Kassmer, Susannah H; Rodriguez, Delany; Langenbacher, Adam D; Bui, Connor; De Tomaso, Anthony W

    2015-01-01

    The colonial ascidian Botryllus schlosseri continuously regenerates entire bodies in an asexual budding process. The germ line of the newly developing bodies is derived from migrating germ cell precursors, but the signals governing this homing process are unknown. Here we show that germ cell precursors can be prospectively isolated based on expression of aldehyde dehydrogenase and integrin alpha-6, and that these cells express germ cell markers such as vasa, pumilio and piwi, as well as sphingosine-1-phosphate receptor. In vitro, sphingosine-1-phosphate (S1P) stimulates migration of germ cells, which depends on integrin alpha-6 activity. In vivo, S1P signalling is essential for homing of germ cells to newly developing bodies. S1P is generated by sphingosine kinase in the developing germ cell niche and degraded by lipid phosphate phosphatase in somatic tissues. These results demonstrate a previously unknown role of the S1P signalling pathway in germ cell migration in the ascidian Botryllus schlosseri. PMID:26456232

  5. SimiRa: A tool to identify coregulation between microRNAs and RNA-binding proteins

    PubMed Central

    Preusse, Martin; Marr, Carsten; Saunders, Sita; Maticzka, Daniel; Lickert, Heiko; Backofen, Rolf; Theis, Fabian

    2015-01-01

    microRNAs and microRNA-independent RNA-binding proteins are 2 classes of post-transcriptional regulators that have been shown to cooperate in gene-expression regulation. We compared the genome-wide target sets of microRNAs and RBPs identified by recent CLIP-Seq technologies, finding that RBPs have distinct target sets and favor gene interaction network hubs. To identify microRNAs and RBPs with a similar functional context, we developed simiRa, a tool that compares enriched functional categories such as pathways and GO terms. We applied simiRa to the known functional cooperation between Pumilio family proteins and miR-221/222 in the regulation of tumor supressor gene p27 and show that the cooperation is reflected by similar enriched categories but not by target genes. SimiRa also predicts possible cooperation of microRNAs and RBPs beyond direct interaction on the target mRNA for the nuclear RBP TAF15. To further facilitate research into cooperation of microRNAs and RBPs, we made simiRa available as a web tool that displays the functional neighborhood and similarity of microRNAs and RBPs: http://vsicb-simira.helmholtz-muenchen.de. PMID:26383775

  6. Arginine vasopressin plasma levels change seasonally in African striped mice but do not differ between alternative reproductive tactics.

    PubMed

    Schoepf, Ivana; Schradin, Carsten

    2014-08-01

    Arginine vasopressin (AVP) is an important hormone for osmoregulation, while as a neuropeptide in the brain it plays an important role in the regulation of social behaviors. Dry habitats are often the home of obligately sociable species such as meerkats and Damaraland mole-rats, leading to the hypothesis that high plasma AVP levels needed for osmoregulation might be associated with the regulation of social behavior. We tested this in a facultative sociable species, the African striped mouse (Rhabdomys pumilio). During the moist breeding season, both solitary- and group-living reproductive tactics occur in this species, which is obligatory sociable in the dry season. We collected 196 plasma samples from striped mice following different reproductive tactics both during the moist and the dry season. Solitary mice did not have lower AVP levels than sociable mice, rejecting the hypothesis that peripheral AVP is involved in the regulation of alternative reproductive tactics. However, we found significantly higher AVP levels during the dry season, with AVP levels correlated with the abundance of food plants, the main source of water for striped mice. Plasma AVP levels were not correlated with testosterone or corticosterone levels. Our study underlines the important role that AVP plays in osmoregulation, particularly for a free ranging mammal living under harsh arid conditions.

  7. A new species of Andinobates (Amphibia: Anura: Dendrobatidae) from west central Panama.

    PubMed

    Batista, Abel; Jaramillo, César A; Ponce, Marcos; Crawford, Andrew J

    2014-01-01

    Dendrobatid frogs are among the best known anurans in the world, mainly due to their toxicity and associated bright colors. A recently described dendrobatid genus, Andinobates, comprises frogs distributed among the Colombian Andes and Panama. During field work in the Distrito de Donoso, Colón province, Panama, we found a poison frog that we here describe as a new species. The new species belongs to the A. minutus species group and is described herein as Andinobates geminisae sp. nov. This new species differs from all other members of the group by having uniformly orange smooth skin over the entire body and a distinctive male advertisement call. The new species is smaller than other colorful dendrobatids present in the area, such as Oophaga pumilio and O. vicentei. We also provide molecular phylogenetic analyses of mitochondrial DNA sequences of dendrobatids and summarize genetic distances among Andinobates species. Andinobates geminisae occurs in Caribbean versant rainforest on the westernmost edge of the known distribution of A. minutus, and represents the fourth species within this genus in Panama. This is vulnerable to habitat loss and excessive harvesting and requires immediate conservation plans to preserve this species with a restricted geographic range. PMID:25283663

  8. Patterns and plasticity in RNA-protein interactions enable recruitment of multiple proteins through a single site

    SciTech Connect

    Valley, Cary T.; Porter, Douglas F.; Qiu, Chen; Campbell, Zachary T.; Tanaka Hall, Traci M.; Wickens, Marvin

    2012-06-28

    mRNA control hinges on the specificity and affinity of proteins for their RNA binding sites. Regulatory proteins must bind their own sites and reject even closely related noncognate sites. In the PUF [Pumilio and fem-3 binding factor (FBF)] family of RNA binding proteins, individual proteins discriminate differences in the length and sequence of binding sites, allowing each PUF to bind a distinct battery of mRNAs. Here, we show that despite these differences, the pattern of RNA interactions is conserved among PUF proteins: the two ends of the PUF protein make critical contacts with the two ends of the RNA sites. Despite this conserved 'two-handed' pattern of recognition, the RNA sequence is flexible. Among the binding sites of yeast Puf4p, RNA sequence dictates the pattern in which RNA bases are flipped away from the binding surface of the protein. Small differences in RNA sequence allow new modes of control, recruiting Puf5p in addition to Puf4p to a single site. This embedded information adds a new layer of biological meaning to the connections between RNA targets and PUF proteins.

  9. Enzymatic activity of rodents acclimated to cold and long scotophase

    NASA Astrophysics Data System (ADS)

    Fourie, F. Le R.; Haim, A.

    1980-09-01

    Rodents representative of a diurnal species ( Rhabdomys pumilio) as well as a nocturnal species ( Praomys natalensis) were acclimated to cold (Ta = 8°C) at a photoperiod of LD 12:12 and a long scotophase (LD 8; 16) at a temperature of 25° C(Ta). Control groups were kept for both species at Ta = 25° C and LD 12:12 and winter acclimated individuals were obtained during July and August to serve as further reference. Blood samples obtained from the tail were analysed for enzymes representative of three major biochemical pathways. The enzymatic activity of LDH (glycolytic pathway), MDH (Krebs cycle) and G6PDH (hexose monophosphate shunt, as an indicator of gonadal activity) were monitored to represent metabolic activity of the respective cycles. Cold acclimated as well as winter acclimatized mice revealed similar enzymatic patterns for both species and significant increases in LDH and MDH were recorded with a concurrent decrease in G6PDH activity. Specimens exposed to long scotophase exhibited similar enzymatic patterns for both species studied, but enzymatic activity was higher than those of cold acclimated individuals. From these results it is concluded that cold as well as long scotophase induce metabolic adaptations through biochemical activity in the experimental animals. The effect of long scotophase is assumed to be an important factor in the induction of winter acclimatization.

  10. Evaluation of a push-pull strategy for the management of Frankliniella bispinosa (Thysanoptera: Thripidae) in bell peppers.

    PubMed

    Tyler-Julian, Kara; Funderburk, Joe; Frantz, Galen; Mellinger, Charles

    2014-10-01

    A push-pull strategy for managing the anthophilous Frankliniella bispinosa (Morgan) in pepper and increasing conservation biological control was evaluated. Push components of ultraviolet (UV)-reflective mulch and foliar applications of kaolin and the pull component of sunflower companion plants were evaluated in replicated field experiments in 2011 and 2012. Adult F. bispinosa rapidly colonized and reproduced in the peppers and sunflowers during early flowering, but populations declined later, as numbers of the predatory Orius insidiosus (Say) and Orius pumilio (Champion) increased in both hosts. Numbers of F. bispinosa were reduced by kaolin during early pepper flowering. Thrips numbers were increased on some of the later sample dates, apparently due to reduced predation that resulted from negative effects of kaolin and UV-reflective mulch on Orius populations. Numbers of thrips increased in peppers with companion plants during the first week of flowering each year, followed by declines in thrips numbers during the next 2 wk in 2011. There was little effect each year of the companion plants on the numbers of Orius in the pepper flowers. There was one date in 2011 and no dates in 2012 in which UV-reflective mulch or kaolin acted in concert with the presence of the companion plants to reduce thrips numbers in the main crop of pepper. Yield effects were not attributed to thrips damage. We conclude that sunflower companion plants did not act additively or synergistically with kaolin or UV-reflective mulch to reduce thrips and increase Orius populations in pepper.

  11. Clonorchis sinensis and Opisthorchis spp. in Vietnam: current status and prospects.

    PubMed

    Doanh, Pham N; Nawa, Yukifumi

    2016-01-01

    Clonorchis sinensis and Opisthorchis viverrini are clinically important small liver flukes because of their known association with development of cholangiocarcinoma. In Vietnam, high prevalence of C. sinensis infection in humans was previously reported in northern provinces, and O. viverrini infection has been detected in several central provinces. However, diagnosis of C. sinensis and O. viverrini infections in the past was merely based on faecal egg examination. This method alone can lead to misidentification at the species level because of morphological similarity between the eggs of these liver flukes and minute intestinal trematodes of the family Heterophyidae. In fact, recent surveys in Vietnam revealed that infection with several minute intestinal flukes, such as Haplorchis pumilio and H. taichui, are much more common than infection with C. sinensis or O. viverrini, and they often co-infect humans. Thus, previously reported prevalence of small liver fluke infection in Vietnam was likely over-estimated due to mis identification of parasites in copro-parasitological examinations. In addition, there is some confusion about identification of cercariae, metacercariae and also adults of C. sinensis and O. viverrini in intermediate and definitive hosts. The aim of this review is, therefore, to draw realistic pictures of the past and present scientific reports on the epidemiology and biology of C. sinensis and Opisthorchis spp. infection in Vietnam.

  12. Target selection by natural and redesigned PUF proteins

    PubMed Central

    Porter, Douglas F.; Koh, Yvonne Y.; VanVeller, Brett; Raines, Ronald T.; Wickens, Marvin

    2015-01-01

    Pumilio/fem-3 mRNA binding factor (PUF) proteins bind RNA with sequence specificity and modularity, and have become exemplary scaffolds in the reengineering of new RNA specificities. Here, we report the in vivo RNA binding sites of wild-type (WT) and reengineered forms of the PUF protein Saccharomyces cerevisiae Puf2p across the transcriptome. Puf2p defines an ancient protein family present throughout fungi, with divergent and distinctive PUF RNA binding domains, RNA-recognition motifs (RRMs), and prion regions. We identify sites in RNA bound to Puf2p in vivo by using two forms of UV cross-linking followed by immunopurification. The protein specifically binds more than 1,000 mRNAs, which contain multiple iterations of UAAU-binding elements. Regions outside the PUF domain, including the RRM, enhance discrimination among targets. Compensatory mutants reveal that one Puf2p molecule binds one UAAU sequence, and align the protein with the RNA site. Based on this architecture, we redesign Puf2p to bind UAAG and identify the targets of this reengineered PUF in vivo. The mutant protein finds its target site in 1,800 RNAs and yields a novel RNA network with a dramatic redistribution of binding elements. The mutant protein exhibits even greater RNA specificity than wild type. The redesigned protein decreases the abundance of RNAs in its redesigned network. These results suggest that reengineering using the PUF scaffold redirects and can even enhance specificity in vivo. PMID:26668354

  13. PREVALENCE OF TREMATODE LARVAE IN INTERMEDIATE HOSTS: SNAILS AND FISH IN KO AE SUB-DISTRICT OF KHUEANG NAI, UBON RATCHATHANI PROVINCE, THAILAND.

    PubMed

    Sripa, Jittiyawadee; Kiatsopit, Nadda; Piratae, Supawadee

    2016-05-01

    Ko Ae Sub-district of Khueang Nai, Ubon Ratchathani Province, Thailand is located in an endemic area for Opisthorchis viverrini and other fish-borne zoonotic trematodes (FZT) infection. This study shows the status in Ko Ae Sub-district of FZT infection based on availability of intermediate hosts and necessary requirements for the transmission of FZT. A cross-sectional survey of intermediate hosts of FZT, including Bithynia siamensis goniomphalos and cyprinoid fish, was conducted from April 2013 to December 2014. Examination of 1,000 snails revealed 3.4% were infected with trematode cercariae, with a density of infection greater than 100 cercariae per infected snail. Six groups of morphologically-distinguishable trematode cercariae were identified, namely, cystophorous, echinostome, furcocercous, mutabile, parapleurolophocercous, and xiphidio, the latter being the most predominant type. Among 250 cyprinoid fish samples with metacercariae present at their caudal fins and examined for FZT by pepsin digestion, metacer- cariae of Haplorchis taichui, H. pumilio, and Centrocestus formosanus were found. Unidentified metacercariae collected from fish caudal fins were subsequently shown using a PCR-based assay to be C. formosanus. No infection by O. viverrini in the intermediate hosts, Bithynia siamensis goniomphalos and cyprinoid fish was evident. The study provides new information regarding trematode larvae infection in the primary and secondary intermediate hosts of FZT in this area of Thailand. PMID:27405122

  14. Isolation and maintenance of Rickettsia raoultii in a Rhipicephalus sanguineus tick cell line.

    PubMed

    Santibáñez, Sonia; Portillo, Aránzazu; Palomar, Ana M; Bell-Sakyi, Lesley; Romero, Lourdes; Oteo, José A

    2015-01-01

    Rickettsia raoultii, a member of the spotted fever group rickettsiae, has been implicated in cases of DEBONEL/TIBOLA/SENLAT, and has been detected in Dermacentor spp. and Rhipicephalus pumilio ticks by PCR. R. raoultii has been isolated in mammalian and tick cell lines. This study aimed to isolate R. raoultii from Spanish Dermacentor marginatus in tick cell lines. A single adult D. marginatus collected from vegetation in La Rioja (Northen Spain) in October 2012 was surface-sterilised, triturated and aliquots of the homogenate were inoculated into a panel of tick cell lines derived from embryonic Rhipicephalus sanguineus, Rhipicephalus evertsi and Ixodes ricinus. Cultures were maintained at 28 °C with weekly medium changes and checked by Gimenez stain for Rickettsia-like intracellular organisms. After 50 days of incubation, intracellular Rickettsia-like organisms were observed in the R. sanguineus cell line RML-RSE using Gimenez stain. PCR assays and sequencing of fragments of 16S RNA, ompB and ompA genes in DNA extracted from the culture suspension showed 100% identity with R. raoultii. Growth of intracellular microorganisms was not observed in preparations of the other tick cell lines. In conclusion, the tick cell line RML-RSE is a useful system for the isolation and maintenance of R. raoultii.

  15. Post-transcriptional gene expression control by NANOS is up-regulated and functionally important in pRb-deficient cells

    PubMed Central

    Miles, Wayne O; Korenjak, Michael; Griffiths, Lyra M; Dyer, Michael A; Provero, Paolo; Dyson, Nicholas J

    2014-01-01

    Inactivation of the retinoblastoma tumor suppressor (pRb) is a common oncogenic event that alters the expression of genes important for cell cycle progression, senescence, and apoptosis. However, in many contexts, the properties of pRb-deficient cells are similar to wild-type cells suggesting there may be processes that counterbalance the transcriptional changes associated with pRb inactivation. Therefore, we have looked for sets of evolutionary conserved, functionally related genes that are direct targets of pRb/E2F proteins. We show that the expression of NANOS, a key facilitator of the Pumilio (PUM) post-transcriptional repressor complex, is directly repressed by pRb/E2F in flies and humans. In both species, NANOS expression increases following inactivation of pRb/RBF1 and becomes important for tissue homeostasis. By analyzing datasets from normal retinal tissue and pRb-null retinoblastomas, we find a strong enrichment for putative PUM substrates among genes de-regulated in tumors. These include pro-apoptotic genes that are transcriptionally down-regulated upon pRb loss, and we characterize two such candidates, MAP2K3 and MAP3K1, as direct PUM substrates. Our data suggest that NANOS increases in importance in pRb-deficient cells and helps to maintain homeostasis by repressing the translation of transcripts containing PUM Regulatory Elements (PRE). PMID:25100735

  16. Target selection by natural and redesigned PUF proteins.

    PubMed

    Porter, Douglas F; Koh, Yvonne Y; VanVeller, Brett; Raines, Ronald T; Wickens, Marvin

    2015-12-29

    Pumilio/fem-3 mRNA binding factor (PUF) proteins bind RNA with sequence specificity and modularity, and have become exemplary scaffolds in the reengineering of new RNA specificities. Here, we report the in vivo RNA binding sites of wild-type (WT) and reengineered forms of the PUF protein Saccharomyces cerevisiae Puf2p across the transcriptome. Puf2p defines an ancient protein family present throughout fungi, with divergent and distinctive PUF RNA binding domains, RNA-recognition motifs (RRMs), and prion regions. We identify sites in RNA bound to Puf2p in vivo by using two forms of UV cross-linking followed by immunopurification. The protein specifically binds more than 1,000 mRNAs, which contain multiple iterations of UAAU-binding elements. Regions outside the PUF domain, including the RRM, enhance discrimination among targets. Compensatory mutants reveal that one Puf2p molecule binds one UAAU sequence, and align the protein with the RNA site. Based on this architecture, we redesign Puf2p to bind UAAG and identify the targets of this reengineered PUF in vivo. The mutant protein finds its target site in 1,800 RNAs and yields a novel RNA network with a dramatic redistribution of binding elements. The mutant protein exhibits even greater RNA specificity than wild type. The redesigned protein decreases the abundance of RNAs in its redesigned network. These results suggest that reengineering using the PUF scaffold redirects and can even enhance specificity in vivo. PMID:26668354

  17. Specificity factors in cytoplasmic polyadenylation.

    PubMed

    Charlesworth, Amanda; Meijer, Hedda A; de Moor, Cornelia H

    2013-01-01

    Poly(A) tail elongation after export of an messenger RNA (mRNA) to the cytoplasm is called cytoplasmic polyadenylation. It was first discovered in oocytes and embryos, where it has roles in meiosis and development. In recent years, however, has been implicated in many other processes, including synaptic plasticity and mitosis. This review aims to introduce cytoplasmic polyadenylation with an emphasis on the factors and elements mediating this process for different mRNAs and in different animal species. We will discuss the RNA sequence elements mediating cytoplasmic polyadenylation in the 3' untranslated regions of mRNAs, including the CPE, MBE, TCS, eCPE, and C-CPE. In addition to describing the role of general polyadenylation factors, we discuss the specific RNA binding protein families associated with cytoplasmic polyadenylation elements, including CPEB (CPEB1, CPEB2, CPEB3, and CPEB4), Pumilio (PUM2), Musashi (MSI1, MSI2), zygote arrest (ZAR2), ELAV like proteins (ELAVL1, HuR), poly(C) binding proteins (PCBP2, αCP2, hnRNP-E2), and Bicaudal C (BICC1). Some emerging themes in cytoplasmic polyadenylation will be highlighted. To facilitate understanding for those working in different organisms and fields, particularly those who are analyzing high throughput data, HUGO gene nomenclature for the human orthologs is used throughout. Where human orthologs have not been clearly identified, reference is made to protein families identified in man.

  18. PolyQ-dependent RNA–protein assemblies control symmetry breaking

    PubMed Central

    Lee, ChangHwan; Occhipinti, Patricia

    2015-01-01

    Dendritic growth in fungi and neurons requires that multiple axes of polarity are established and maintained within the same cytoplasm. We have discovered that transcripts encoding key polarity factors including a formin, Bni1, and a polarisome scaffold, Spa2, are nonrandomly clustered in the cytosol to initiate and maintain sites of polarized growth in the fungus Ashbya gossypii. This asymmetric distribution requires the mRNAs to interact with a polyQ-containing protein, Whi3, and a Pumilio protein with a low-complexity sequence, Puf2. Cells lacking Whi3 or Puf2 had severe defects in establishing new sites of polarity and failed to localize Bni1 protein. Interaction of mRNAs with Whi3 and Puf2 promotes enrichment of transcripts at established sites of polarized growth and clustering of polarity transcripts throughout the cell body. Thus, aggregation-prone proteins make functional assemblies to position polarity transcripts, and nonrandom positioning of transcripts is required for symmetry-breaking events. This reveals a physiological function for polyQ-driven assemblies in regulating cell polarity. PMID:25713414

  19. Futile attempts to differentiate provide molecular evidence for individual differences within a population of cells during cellular reprogramming.

    PubMed

    Hoffmann, Xenia-Katharina; Tesmer, Jens; Souquet, Manfred; Marwan, Wolfgang

    2012-04-01

    The heterogeneity of cell populations and the influence of stochastic noise might be important issues for the molecular analysis of cellular reprogramming at the system level. Here, we show that in Physarum polycephalum, the expression patterns of marker genes correlate with the fate decision of individual multinucleate plasmodial cells that had been exposed to a differentiation-inducing photostimulus. For several hours after stimulation, the expression kinetics of PI-3-kinase, piwi, and pumilio orthologs and other marker genes were qualitatively similar in all stimulated cells but quantitatively different in those cells that subsequently maintained their proliferative potential and failed to differentiate accordingly. The results suggest that the population of nuclei in an individual plasmodium behaves synchronously in terms of gene regulation to an extent that the plasmodium provides a source for macroscopic amounts of homogeneous single-cell material for analysing the dynamic processes of cellular reprogramming. Based on the experimental findings, we predict that circuits with switch-like behaviour that control the cell fate decision of a multinucleate plasmodium operate through continuous changes in the concentration of cellular regulators because the nuclear population suspended in a large cytoplasmic volume damps stochastic noise.

  20. Prevalence of fish-borne trematodes of the family Heterophyidae at Pasak Cholasid Reservoir, Thailand.

    PubMed

    Krailas, D; Veeravechsukij, N; Chuanprasit, C; Boonmekam, D; Namchote, S

    2016-04-01

    The prevalence of fish-borne trematodes was investigated in various species of freshwater fish at Pasak Cholasid Reservoir in Thailand. The samples were collected from fish markets around the reservoir between June 2011 and May 2012. A total of 789 fish samples were classified into 25 species. The metacercariae (i.e., the larval stage of trematodes) were examined from 4 parts of the fish body, and evaluated using the compression method. Ten species from two families of the fish collected were found to have trematodes of various infection rates. Among the Cyprinidae there were 9 species: Barbonymus altus (100%; 14/14), Barbonymus schwanenfeldii (88.71%; 55/62), Cyclocheilichthys enoplos (49.53%; 53/107), Hampala dispar (66.67%; 6/9), Henicorhynchus siamensis (23.36%; 25/107), Hypsibarbus wetmorei (85.29%; 58/68), Labiobarbus siamensis (77.78%; 56/72), Osteochilus hasseltii (16.28%; 7/43), and Puntioplites proctozysron (53.97%; 34/63). Among the Eleotridae, only one species Oxyeleotris marmorata was found with an infection rate of 20% (2/10). Based on morphological features and corroborated by molecular genetic data, the fish trematodes were found to represent two species of the Heterophyidae, viz. Haplorchis pumilio and Centrocestus formosanus. Thus, it is evident that freshwater fish from the Pasak Cholasid Reservoir exhibit heterophyid trematode infections.

  1. Metacercariae in fishes of Sun Moon lake which is an endemic area for Clonorchis sinensis in Taiwan.

    PubMed

    Ooi, H K; Chen, C I; Lin, S C; Tung, K C; Wang, J S; Kamiya, M

    1997-01-01

    The Sun Moon lake in Central Taiwan is a known endemic area for clonorchiasis. Of the 45 fresh water fish, Hemiculter leucisculus, from the lake that were examined by artificial gastric juice digestion in October 1995, all were found to harbor metacercariae in their muscle. The number of metacercariae isolated from each fish ranged from 2 to 2,185, with an average of 254. A total of 11,443 metacercariae was collected from the 45 fish. Of the 4,223 metacercaria that were examined under light microscope, 4,064 (96.23%) were found to belong to Haplorchis taichui, 90(2.13%) to H. pumilio, 2(0.05%) to C. sinensis and 67 (1.59%) to unknown species due to the metacercariae being not yet developed or immature. The 2 C. sinensis metacercariae were obtained from 2 out of 45 fish examined. Our results contrast with reports of a decade ago which stated that all the fish of the Sun Moon lake examined were positive for C. sinensis. Possible reasons for the decrease of C. sinensis metacercariae are the disappearance of pig farms around the lake, increased awareness of the trematode by the lakeside inhabitants and probably the exclusive use of mammals as its definitive host by C. sinensis. In contrast, besides mammals, Haplorchis spp also use birds as their definitive hosts.

  2. Arginine vasopressin plasma levels change seasonally in African striped mice but do not differ between alternative reproductive tactics.

    PubMed

    Schoepf, Ivana; Schradin, Carsten

    2014-08-01

    Arginine vasopressin (AVP) is an important hormone for osmoregulation, while as a neuropeptide in the brain it plays an important role in the regulation of social behaviors. Dry habitats are often the home of obligately sociable species such as meerkats and Damaraland mole-rats, leading to the hypothesis that high plasma AVP levels needed for osmoregulation might be associated with the regulation of social behavior. We tested this in a facultative sociable species, the African striped mouse (Rhabdomys pumilio). During the moist breeding season, both solitary- and group-living reproductive tactics occur in this species, which is obligatory sociable in the dry season. We collected 196 plasma samples from striped mice following different reproductive tactics both during the moist and the dry season. Solitary mice did not have lower AVP levels than sociable mice, rejecting the hypothesis that peripheral AVP is involved in the regulation of alternative reproductive tactics. However, we found significantly higher AVP levels during the dry season, with AVP levels correlated with the abundance of food plants, the main source of water for striped mice. Plasma AVP levels were not correlated with testosterone or corticosterone levels. Our study underlines the important role that AVP plays in osmoregulation, particularly for a free ranging mammal living under harsh arid conditions. PMID:24842715

  3. Migration of germline progenitor cells is directed by sphingosine-1-phosphate signalling in a basal chordate

    PubMed Central

    Kassmer, Susannah H.; Rodriguez, Delany; Langenbacher, Adam D.; Bui, Connor; De Tomaso, Anthony W.

    2015-01-01

    The colonial ascidian Botryllus schlosseri continuously regenerates entire bodies in an asexual budding process. The germ line of the newly developing bodies is derived from migrating germ cell precursors, but the signals governing this homing process are unknown. Here we show that germ cell precursors can be prospectively isolated based on expression of aldehyde dehydrogenase and integrin alpha-6, and that these cells express germ cell markers such as vasa, pumilio and piwi, as well as sphingosine-1-phosphate receptor. In vitro, sphingosine-1-phosphate (S1P) stimulates migration of germ cells, which depends on integrin alpha-6 activity. In vivo, S1P signalling is essential for homing of germ cells to newly developing bodies. S1P is generated by sphingosine kinase in the developing germ cell niche and degraded by lipid phosphate phosphatase in somatic tissues. These results demonstrate a previously unknown role of the S1P signalling pathway in germ cell migration in the ascidian Botryllus schlosseri. PMID:26456232

  4. A universal strategy for regulating mRNA translation in prokaryotic and eukaryotic cells.

    PubMed

    Cao, Jicong; Arha, Manish; Sudrik, Chaitanya; Mukherjee, Abhirup; Wu, Xia; Kane, Ravi S

    2015-04-30

    We describe a simple strategy to control mRNA translation in both prokaryotic and eukaryotic cells which relies on a unique protein-RNA interaction. Specifically, we used the Pumilio/FBF (PUF) protein to repress translation by binding in between the ribosome binding site (RBS) and the start codon (in Escherichia coli), or by binding to the 5' untranslated region of target mRNAs (in mammalian cells). The design principle is straightforward, the extent of translational repression can be tuned and the regulator is genetically encoded, enabling the construction of artificial signal cascades. We demonstrate that this approach can also be used to regulate polycistronic mRNAs; such regulation has rarely been achieved in previous reports. Since the regulator used in this study is a modular RNA-binding protein, which can be engineered to target different 8-nucleotide RNA sequences, our strategy could be used in the future to target endogenous mRNAs for regulating metabolic flows and signaling pathways in both prokaryotic and eukaryotic cells.

  5. An experimental test for age-related improvements in reproductive performance in a frog that cares for its young

    NASA Astrophysics Data System (ADS)

    Dugas, Matthew B.; Moore, Michael P.; Wamelink, Caitlin N.; Richards-Zawacki, Corinne L.; Martin, Ryan A.

    2015-10-01

    Reproductive performance often increases with age in long-lived iteroparous organisms, a pattern that can result from within-individual increases in effort and/or competence. In free-living populations, it is typically difficult to distinguish these mechanisms or to isolate particular features of reproduction-influencing outcomes. In captive Oophaga pumilio, a frog in which mothers provide extended offspring provisioning via trophic eggs, we experimentally manipulated the age at which females started breeding and then monitored them across repeated reproductive events. This experiment allowed us to decouple age and experience and isolate maternal care as the proximate source of any differences in performance. Younger first-time mothers produced larger broods than older first-time mothers, but did not rear more offspring to independence. Across repeated reproductive events, maternal age was unassociated with any metric of performance. At later reproductive events, however, mothers produced fewer metamorphs, and a lower proportion of individuals in their broods reached independence. These patterns suggest that performance does not improve with age or breeding experience in this frog, and that eventual declines in performance are driven by reproductive activity, not age per se. Broadly, age-specific patterns of reproductive performance may depend on the proximate mechanism by which parents influence offspring fitness and how sensitive these are to effort and competence.

  6. Evaluation of a push-pull strategy for the management of Frankliniella bispinosa (Thysanoptera: Thripidae) in bell peppers.

    PubMed

    Tyler-Julian, Kara; Funderburk, Joe; Frantz, Galen; Mellinger, Charles

    2014-10-01

    A push-pull strategy for managing the anthophilous Frankliniella bispinosa (Morgan) in pepper and increasing conservation biological control was evaluated. Push components of ultraviolet (UV)-reflective mulch and foliar applications of kaolin and the pull component of sunflower companion plants were evaluated in replicated field experiments in 2011 and 2012. Adult F. bispinosa rapidly colonized and reproduced in the peppers and sunflowers during early flowering, but populations declined later, as numbers of the predatory Orius insidiosus (Say) and Orius pumilio (Champion) increased in both hosts. Numbers of F. bispinosa were reduced by kaolin during early pepper flowering. Thrips numbers were increased on some of the later sample dates, apparently due to reduced predation that resulted from negative effects of kaolin and UV-reflective mulch on Orius populations. Numbers of thrips increased in peppers with companion plants during the first week of flowering each year, followed by declines in thrips numbers during the next 2 wk in 2011. There was little effect each year of the companion plants on the numbers of Orius in the pepper flowers. There was one date in 2011 and no dates in 2012 in which UV-reflective mulch or kaolin acted in concert with the presence of the companion plants to reduce thrips numbers in the main crop of pepper. Yield effects were not attributed to thrips damage. We conclude that sunflower companion plants did not act additively or synergistically with kaolin or UV-reflective mulch to reduce thrips and increase Orius populations in pepper. PMID:25199151

  7. Plesiosaur-bearing rocks from the Late Cretaceous Tahora Fm, Mangahouanga, New Zealand - a palaeoenvironmental study

    NASA Astrophysics Data System (ADS)

    Vajda, Vivi; Raine, J. Ian

    2010-05-01

    Mangahouanga Stream, Hawkes Bay, New Zealand is world-famous for its high southern latitude vertebrate fossils including plesiosaurs, mosasaurs and more rarely, dinosaurs. The fossils are preserved in the conglomeratic facies of the Maungataniwha Sandstone Member of the Tahora Formation. A palynological investigation of sediments from the boulders hosting vertebrate fossils reveals well-preserved palynological assemblages dominated by pollen and spores from land plants but also including marine dinoflagellate cysts in one sample. The palynofacies is strongly dominated by wood fragments including charcoal, and the sample taken from a boulder hosting plesiosaur vertebrae is entirely terrestrially derived, suggesting a fresh-water habitat for at least some of these plesiosaurs. The key-pollen taxa Nothofagidites senectus and Tricolpites lilliei, together with the dinocyst Isabelidinium pellucidum and the megaspore Grapnelispora evansii, strongly indicate an early Maastrichtian age for the host rock. The terrestrial palynoflora reflects a mixed vegetation dominated by podocarp conifers and angiosperms with a significant tree-fern subcanopy component. The presence of taxa with modern temperate distributions such as Nothofagus (southern beech), Proteaceae and Cyatheaceae (tree-ferns), indicates a mild-temperate climate and lack of severe winter freezing during the latest Cretaceous, providing an ecosystem which most probably made it possible for polar dinosaurs to overwinter. The paper is dedicated to Mrs Joan Wiffen who with her great persistence, enthusiasm and courage put Mangahouanga on the world map, becoming a role model for many young scientists.

  8. Virtual Screening of Plant Volatile Compounds Reveals a High Affinity of Hylamorpha elegans (Coleoptera: Scarabaeidae) Odorant-Binding Proteins for Sesquiterpenes From Its Native Host.

    PubMed

    González-González, Angélica; Palma-Millanao, Rubén; Yáñez, Osvaldo; Rojas, Maximiliano; Mutis, Ana; Venthur, Herbert; Quiroz, Andrés; Ramírez, Claudio C

    2016-01-01

    Hylamorpha elegans(Burmeister) is a native Chilean scarab beetle considered to be a relevant agricultural pest to pasture and cereal and small fruit crops. Because of their cryptic habits, control with conventional methods is difficult; therefore, alternative and environmentally friendly control strategies are highly desirable. The study of proteins that participate in the recognition of odorants, such as odorant-binding proteins (OBPs), offers interesting opportunities to identify new compounds with the potential to modify pest behavior and computational screening of compounds, which is commonly used in drug discovery, may help to accelerate the discovery of new semiochemicals. Here, we report the discovery of four OBPs inH. elegans as well as six new volatiles released by its native host Nothofagus obliqua(Mirbel). Molecular docking performed between OBPs and new and previously reported volatiles from N. oblique revealed the best binding energy values for sesquiterpenic compounds. Despite remarkable divergence at the amino acid level, three of the four OBPs evaluated exhibited the best interaction energy for the same ligands. Molecular dynamics investigation reinforced the importance of sesquiterpenes, showing that hydrophobic residues of the OBPs interacted most frequently with the tested ligands, and binding free energy calculations demonstrated van der Waals and hydrophobic interactions to be the most important. Altogether, the results suggest that sesquiterpenes are interesting candidates for in vitro and in vivo assays to assess their potential application in pest management strategies.

  9. Antarctic glacial geologic record and GCM modeling: A test

    SciTech Connect

    Elliot, D.H.; Bromwich, D.H.; Harwood, D.M.; Webb, P.

    1992-03-01

    A recent GCM (General Circulation Model) study of Antarctic glaciation by Oglesby concluded that (1) oceanic heat transport is relatively unimportant in the development and maintenance of Antarctic glaciation; (2) height and polar position, not the Antarctic Circumpolar Current, have led to thermal isolation; and (3) surface elevation may be crucial for glaciation. Model results are here evaluated against the Pliocene geologic record for Antarctica. The Sirius Group, widely distributed in the Transantarctic Mountains, contains diatom floras suggesting open marine conditions in interior East Antarctica as recently as about 3 m.y. ago. The Sirius deposits also contain a sparse fossil flora including Nothofagus wood, demonstrating snow-free conditions and elevated summer temperatures within 500 km of the South Pole. Based on fission track data and marine sediments, uplift rates for the Transantarctic Mountains are estimated to average 50-100 m m.y.-1 for the last 10 m.y., although rates may have been higher during the last 3 m.y. The continental interior is also most unlikely to have changed elevation by more than a few hundred meters in the last 3 m.y. If the dating of the Sirius is correct and uplift rates have not been an order of magnitude higher, then polar location and elevation cannot be primary controls on the formation and subsequent fluctuations of the ice sheet.

  10. Microbe domestication and the identification of the wild genetic stock of lager-brewing yeast

    PubMed Central

    Libkind, Diego; Hittinger, Chris Todd; Valério, Elisabete; Gonçalves, Carla; Dover, Jim; Johnston, Mark; Gonçalves, Paula; Sampaio, José Paulo

    2011-01-01

    Domestication of plants and animals promoted humanity's transition from nomadic to sedentary lifestyles, demographic expansion, and the emergence of civilizations. In contrast to the well-documented successes of crop and livestock breeding, processes of microbe domestication remain obscure, despite the importance of microbes to the production of food, beverages, and biofuels. Lager-beer, first brewed in the 15th century, employs an allotetraploid hybrid yeast, Saccharomyces pastorianus (syn. Saccharomyces carlsbergensis), a domesticated species created by the fusion of a Saccharomyces cerevisiae ale-yeast with an unknown cryotolerant Saccharomyces species. We report the isolation of that species and designate it Saccharomyces eubayanus sp. nov. because of its resemblance to Saccharomyces bayanus (a complex hybrid of S. eubayanus, Saccharomyces uvarum, and S. cerevisiae found only in the brewing environment). Individuals from populations of S. eubayanus and its sister species, S. uvarum, exist in apparent sympatry in Nothofagus (Southern beech) forests in Patagonia, but are isolated genetically through intrinsic postzygotic barriers, and ecologically through host-preference. The draft genome sequence of S. eubayanus is 99.5% identical to the non-S. cerevisiae portion of the S. pastorianus genome sequence and suggests specific changes in sugar and sulfite metabolism that were crucial for domestication in the lager-brewing environment. This study shows that combining microbial ecology with comparative genomics facilitates the discovery and preservation of wild genetic stocks of domesticated microbes to trace their history, identify genetic changes, and suggest paths to further industrial improvement. PMID:21873232

  11. Bridging the "beech-gap": New Zealand invertebrate phylogeography implicates Pleistocene glaciation and Pliocene isolation.

    PubMed

    Trewick, S A; Wallis, G P

    2001-11-11

    The existence of areas of lower endemism and disjunction of New Zealand biota is typified by Nothofagus beech trees (hence "beech-gap") and have been attributed to a variety of causes ranging from ancient fault-mediated displacement (20-25 million years ago) to Pleistocene glacial extirpation (< 1.8 million years ago). We used cytochrome oxidase I and 12S mtDNA sequence data from a suite of endemic invertebrates to explore phylogeographic depth and patterns in South Island, New Zealand, where the "beech-gap" occurs. Phylogeographic structure and genetic distance data are not consistent with ancient vicariant processes as a source of observed pattern. However, we also find that phylogeographic patterns are not entirely congruent and appear to reflect disparate responses to fragmentation, which we term "gap," "colonization," and "regional." Radiations among congenerics, and in at least one instance within a species, probably took place in the Pliocene (2-7 million years ago), possibly under the influence of the onset of mountain building. This orogenic phase may have had a considerable impact on the development of the biota generally. Some of the taxa that we studied do not appear to have suffered range reduction during Pleistocene glaciation, consistent with their survival throughout that epoch in alpine habitats to which they are adapted. Other taxa have colonized the beech-gap recently (i.e., after glaciation), whereas few among our sample retain evidence of extirpation in the most heavily glaciated zone.

  12. Palynological analysis of camelid coprolites: seasonality in the use of the site Cerro Casa de Piedra 7 (Santa Cruz, Argentina)

    NASA Astrophysics Data System (ADS)

    Velázquez, Nadia Jimena; Burry, Lidia Susana; Fugassa, Martín Horacio; Civalero, María Teresa; Aschero, Carlos Alberto

    2014-01-01

    Palynological, palaeoparasitological and paleobotanical studies of coprolites found in archaeological sites from Perito Moreno National Park (47°57‧S72°05‧W) yielded information on diet, palaeoenvironment and health. These studies allowed adding evidence to the reconstruction of life history of the hunter-gatherers that inhabited Patagonia during the Holocene. We examined the season of the year when camelid Lama guanicoe coprolites (5400 ± 64 yr 14C BP to 9640 ± 190 yr 14C BP) were deposited at Cerro Casa de Piedra 7 (site CCP7). The study used palynological evidence and comparison with pollen spectra of modern feces collected during summer, fall, winter and spring of 2010. The dominant types were: pollen of Nothofagus, Empetrum rubrum, Asteraceae subfam. Asteroideae, Nassauvia, Caryophyllaceae and Poaceae; fern spores; remains of Eimeria macusaniensis; and plant remains of Poaceae, Festuca pallescens, Stipa speciosa, Armeria maritima, Gaultheria mucronata and E. rubrum. Pollen spectra of modern and fossil feces were used for multivariate analysis. Coprolites associated to fall and winter modern feces. These results and those obtained from pollen concentration values and the presence of pollen types indicators of seasonality, allowed the determination of summer, fall and winter coprolites. However, caution must be taken with the seasonality results of coprolites dated earlier than 9000 years BP since the environmental conditions differed from now. The site was probably a camelid shelter during the unfavorable seasons.

  13. Baseline element composition of foliose and fruticose lichens along the steep climatic gradient of SW Patagonia (Aisén Region, Chile).

    PubMed

    Monaci, Fabrizio; Fantozzi, Federica; Figueroa, Ricardo; Parra, Oscar; Bargagli, Roberto

    2012-09-01

    Samples of foliose (Nephroma antarcticum) and fruticose (Usnea sp.) lichens were collected across a steep climatic and vegetation gradient in a remote, almost pristine region of SW Chilean Patagonia. Concentrations of major and trace elements in lichens from the rainforest were among the lowest ever reported worldwide for foliose and fruticose lichens and can be considered background levels for the region. The two lichen growth forms showed different elemental compositions mainly due to the greater capacity of foliose thalli to intercept elements from windborne and canopy-leached particles. The patterns of spatial variation in the chemical composition of lichens were effectively explained by statistical methods and reflected the different availability of wet and dry deposition along the steep climatic gradient. Baseline values established for N. antarcticum samples growing in temperate Nothofagus forests were therefore distinct from those of samples growing in more open, drier habitats. The fruticose Usnea sp. showed a higher affinity for atmophile Hg, low concentrations of lithophilic elements, and the same baseline composition whether from temperate forests or from dry, barren environments. The provided background and baseline values against which variations can be measured will be useful in the early detection of local or regional climatic and environmental change, especially in view of the planned construction of hydropower dams under the recently approved HidroAysén Project. PMID:22790117

  14. Males of Hylamorpha elegans burmeister (Coleoptera: Scarabaeidae) are attracted to odors released from conspecific females.

    PubMed

    Quiroz, Andrés; Palma, Ruben; Etcheverría, Paulina; Navarro, Vicente; Rebolledo, Ramón

    2007-04-01

    The behavioral responses of Hylamorpha elegans L. (Coleoptera: Scarabaeidae, Rutelinae) to the semiochemicals released from conspecific individual adults were studied, with particular attention paid to female attraction of males. Odors released from virgin females significantly attracted male conspecifics in both the field and laboratory olfactometer and wind tunnel bioassays. However, females did not attract other females, and males attracted no one. The response of male H. elegans to (1) compounds (1,4-hydroquinone and 1,4-benzoquinone) released only by unmated females; (2) the essential oil of the secondary host (Nothofagus obliqua); and (3) the blend of 1,4-hydroquinone and 1,4-benzoquinone with N. obliqua essential oil was studied. The blend of 1,4-benzoquinone mixed with essential oil at the trial concentration was attractive with males. The same response was found with 1,4-hydroquinone alone. The essential oil did not have the expected attractant effect on conspecific males. These results suggest that, when combined with essential oil, 1,4-benzoquinone may function in the sexual behavior of males and females. These findings are discussed in terms of the ecological role of this putative sexual pheromone and its potential use in a strategy of control of this pest.

  15. Gregarious bamboo flowering opens a window of opportunity for regeneration in a temperate forest of Patagonia.

    PubMed

    Giordano, Carla V; Sánchez, Rodolfo A; Austin, Amy T

    2009-03-01

    Rare gregarious flowering of understorey bamboo species occurs in temperate and subtropical forests around the world, but the ecological consequences of this phenomenon for forest regeneration are not well understood.Field experiments were conducted in an old-growth temperate forest in Patagonia,Argentina after a massive bamboo flowering event, to examine whether light quality and other changes in microhabitats could affect seed germination and growth of overstorey species. Germination of southern beech (Nothofagus obliqua) was positively correlated with red:far red (R:FR) ratios in a range of microhabitats generated by the death of the understorey bamboo (Chusquea culeou). Experimental modification of understorey R:FR ratios to mimic alternative light environments reversed this germination response in plots with senescent understorey, but not in plots with live bamboo. Laboratory incubations demonstrated a significant interaction between R:FR ratios and thermal amplitude in promoting seed germination. Microhabitats also significantly affected the growth of emerged seedlings. Microenvironmental changes generated by this flowering event appear to have opened a window of opportunity for germination and growth of overstorey species.We demonstrate that natural gradients in light quality associated with this ecological phenomenon are a major component affecting forest regeneration in this ecosystem.

  16. Vicariant origin of malagasy reptiles supports late cretaceous antarctic land bridge.

    PubMed

    Noonan, Brice P; Chippindale, Paul T

    2006-12-01

    Since the acceptance of Wegener's theory of plate tectonics in the 1960s, continental drift vicariance has been proposed as an explanation for pan-Gondwanan faunal distributions. Given the recognition of historical connections among continents, it no longer was necessary to invoke hypotheses of dispersal across nearly insurmountable barriers. The application of continental drift vicariance theory to Gondwanan floral and faunal distributions provided reasonable explanations for such unusual distributions as that of the southern beech (Nothofagus) and chameleons. However, recent studies have demonstrated a significant, if not dominant, role for dispersal in the present-day distributions of these and numerous other "Gondwanan" taxa. The evolutionary histories of three Malagasy groups (boid snakes, podocnemid turtles, and iguanid lizards) commonly have been interpreted as reflecting vicariance because of continental drift associated with the breakup of Gondwana. Bayesian analyses of divergence ages suggest that this pattern is the result of vicariance coincident with the isolation of Madagascar in the Late Cretaceous (approximately 80 million years ago). This represents the first temporal evidence linking the vicariant origin of extant Malagasy vertebrates to a single geologic event. Specifically, our data provide strong, independently corroborated evidence for a contiguous Late Cretaceous Gondwana, exclusive of Africa and connected via Antarctica.

  17. Virtual Screening of Plant Volatile Compounds Reveals a High Affinity of Hylamorpha elegans (Coleoptera: Scarabaeidae) Odorant-Binding Proteins for Sesquiterpenes From Its Native Host

    PubMed Central

    Palma-Millanao, Rubén; Yáñez, Osvaldo; Rojas, Maximiliano; Mutis, Ana; Venthur, Herbert; Quiroz, Andrés; Ramírez, Claudio C.

    2016-01-01

    Hylamorpha elegans (Burmeister) is a native Chilean scarab beetle considered to be a relevant agricultural pest to pasture and cereal and small fruit crops. Because of their cryptic habits, control with conventional methods is difficult; therefore, alternative and environmentally friendly control strategies are highly desirable. The study of proteins that participate in the recognition of odorants, such as odorant-binding proteins (OBPs), offers interesting opportunities to identify new compounds with the potential to modify pest behavior and computational screening of compounds, which is commonly used in drug discovery, may help to accelerate the discovery of new semiochemicals. Here, we report the discovery of four OBPs in H. elegans as well as six new volatiles released by its native host Nothofagus obliqua (Mirbel). Molecular docking performed between OBPs and new and previously reported volatiles from N. obliqua revealed the best binding energy values for sesquiterpenic compounds. Despite remarkable divergence at the amino acid level, three of the four OBPs evaluated exhibited the best interaction energy for the same ligands. Molecular dynamics investigation reinforced the importance of sesquiterpenes, showing that hydrophobic residues of the OBPs interacted most frequently with the tested ligands, and binding free energy calculations demonstrated van der Waals and hydrophobic interactions to be the most important. Altogether, the results suggest that sesquiterpenes are interesting candidates for in vitro and in vivo assays to assess their potential application in pest management strategies. PMID:27012867

  18. Baseline element composition of foliose and fruticose lichens along the steep climatic gradient of SW Patagonia (Aisén Region, Chile).

    PubMed

    Monaci, Fabrizio; Fantozzi, Federica; Figueroa, Ricardo; Parra, Oscar; Bargagli, Roberto

    2012-09-01

    Samples of foliose (Nephroma antarcticum) and fruticose (Usnea sp.) lichens were collected across a steep climatic and vegetation gradient in a remote, almost pristine region of SW Chilean Patagonia. Concentrations of major and trace elements in lichens from the rainforest were among the lowest ever reported worldwide for foliose and fruticose lichens and can be considered background levels for the region. The two lichen growth forms showed different elemental compositions mainly due to the greater capacity of foliose thalli to intercept elements from windborne and canopy-leached particles. The patterns of spatial variation in the chemical composition of lichens were effectively explained by statistical methods and reflected the different availability of wet and dry deposition along the steep climatic gradient. Baseline values established for N. antarcticum samples growing in temperate Nothofagus forests were therefore distinct from those of samples growing in more open, drier habitats. The fruticose Usnea sp. showed a higher affinity for atmophile Hg, low concentrations of lithophilic elements, and the same baseline composition whether from temperate forests or from dry, barren environments. The provided background and baseline values against which variations can be measured will be useful in the early detection of local or regional climatic and environmental change, especially in view of the planned construction of hydropower dams under the recently approved HidroAysén Project.

  19. Saccharomyces eubayanus and Saccharomyces uvarum associated with the fermentation of Araucaria araucana seeds in Patagonia.

    PubMed

    Rodríguez, M Eugenia; Pérez-Través, Laura; Sangorrín, Marcela P; Barrio, Eladio; Lopes, Christian A

    2014-09-01

    Mudai is a traditional fermented beverage, made from the seeds of the Araucaria araucana tree by Mapuche communities. The main goal of the present study was to identify and characterize the yeast microbiota responsible of Mudai fermentation as well as from A. araucana seeds and bark from different locations in Northern Patagonia. Only Hanseniaspora uvarum and a commercial bakery strain of Saccharomyces cerevisiae were isolated from Mudai and all Saccharomyces isolates recovered from A. araucana seed and bark samples belonged to the cryotolerant species Saccharomyces eubayanus and Saccharomyces uvarum. These two species were already reported in Nothofagus trees from Patagonia; however, this is the first time that they were isolated from A. araucana, which extends their ecological distribution. The presence of these species in A. araucana seeds and bark samples, led us to postulate a potential role for them as the original yeasts responsible for the elaboration of Mudai before the introduction of commercial S. cerevisiae cultures. The molecular and genetic characterization of the S. uvarum and S. eubayanus isolates and their comparison with European S. uvarum strains and S. eubayanus hybrids (S. bayanus and S. pastorianus), allowed their ecology and evolution us to be examined.

  20. Dendrogeomorphic reconstruction of flash floods in the Patagonian Andes

    NASA Astrophysics Data System (ADS)

    Casteller, Alejandro; Stoffel, Markus; Crespo, Sebastián; Villalba, Ricardo; Corona, Christophe; Bianchi, Emilio

    2015-01-01

    Flash floods represent a significant natural hazard in small mountainous catchments of the Patagonian Andes and have repeatedly caused loss to life and infrastructure. At the same time, however, documentary records of past events remain fairly scarce and highly fragmentary in most cases. In this study, we therefore reconstruct the spatiotemporal patterns of past flash flood activity along the Los Cipreses torrent (Neuquén, Argentina) using dendrogeomorphic methods. Based on samples from Austrocedrus chilensis, Pseudotsuga menziesii, and Nothofagus dombeyi, we document 21 flash flood events covering the period A.D. 1890-2009 and reconstruct mean recurrence intervals of events at the level of individual trees being impacted, which varies from 4 to 93 years. Results show that trees tend to be older (younger) in sectors of the torrent with gentler (steeper) slope gradients. Potential triggers of flash floods were analyzed using daily temperature and precipitation data from a nearby weather station. Weather conditions leading to flash floods are abundant precipitations during one to three consecutive days, combined with temperatures above the rain/snow threshold (2 °C) in the whole watershed.

  1. Late Glacial beech forest: an 18,000 5000-BP pollen record from Auckland, New Zealand

    NASA Astrophysics Data System (ADS)

    Lancashire, A. K.; Flenley, J. R.; Harper, M.

    2002-07-01

    Australia, New Zealand and South America are the main sources of terrestrial climate change records for midlatitudes in the Southern Hemisphere. The advantage of studying the New Zealand record is that its vegetation has been subject to human influence for only the last thousand years. Vegetation records for Auckland are important because earlier work indicates that during the Last Glacial Maximum, the boundary between scrubland and forest lay in the Auckland region. Auckland is situated in a volcanic field and the coring site was in the crater of a small extinct volcano (Crater Hill, formed about 29 ka BP). The 4-m long core contained sediment dating from c. 5 to c. 18 ka BP. We present pollen and diatom records from this core. The pollen records from basal clays indicate southern beech forest (mainly Nothofagus menziesii) was present in the region around Crater Hill from 18 to 14.5 ka BP. At this time, there were areas of scrub in the crater surrounding a hardwater lake. The southern forest limit could well have been close to the site. Records from overlying peat indicate beech forest was replaced by Podocarp broadleaf forest as the Last Glacial ended. Metrosideros spp. (coastal forest trees) peak in the early Holocene. This coincides with an impoverished diatom flora which indicates drier conditions in the basin. When the lake reformed in the Holocene on peat its water was more acidic.

  2. Net primary production of forests: a constant fraction of gross primary production?

    PubMed

    Waring, R. H.; Landsberg, J. J.; Williams, M.

    1998-02-01

    Considerable progress has been made in our ability to model and measure annual gross primary production (GPP) by terrestrial vegetation. But challenges remain in estimating maintenance respiration (R(m)) and net primary production (NPP). To search for possible common relationships, we assembled annual carbon budgets from six evergreen and one deciduous forest in Oregon, USA, three pine plantations in New South Wales, Australia, a deciduous forest in Massachusetts, USA, and a Nothofagus forest on the South Island of New Zealand. At all 12 sites, a standard procedure was followed to estimate annual NPP of foliage, branches, stems, and roots, the carbon expended in synthesis of these organs (R(g)), their R(m), and that of previously produced foliage and sapwood in boles, branches, and large roots. In the survey, total NPP ranged from 120 to 1660 g C m(-2) year(-1), whereas the calculated fraction allocated to roots varied from 0.22 to 0.63. Comparative analysis indicated that the total NPP/GPP ratio was conservative (0.47 +/- 0.04 SD). This finding supports the possibility of greatly simplifying forest growth models. The constancy of the NPP/GPP ratio also provides an incentive to renew efforts to understand the environmental factors affecting partitioning of NPP above and belowground.

  3. Inquiring into the causes of depressed folivory in a fragmented temperate forest

    NASA Astrophysics Data System (ADS)

    Silva, Claudia A.; Simonetti, Javier A.

    2009-05-01

    Folivory is lower in forest fragments of the Maulino forest than in continuous stands. We experimentally assessed whether depressed folivory is related to a reduction in foliar palatability caused by the more xeric microclimate of forest fragments. We compared leaf anatomy at fragments and continuous forest for four tree species ( Aristotelia chilensis, Cryptocarya alba, Nothofagus glauca and Gevuina avellana), and evaluated consumption of leaves of the two different habitats by insect species ( Sericoides viridis and Ormiscodes rufosignata). Anatomy of leaves of fragments differs from that from continuous forest in at least one of the traits, for all the plant species. However, not all species exhibit more sclerophyllous traits in forest fragments. A. chilensis exhibits the greatest number of changes, being more sclerophyllous in fragments. In palatability trials, there were no differences in the consumption of leaves of fragments versus leaves of continuous forest. Therefore, depressed folivory levels in forest remnants of the Maulino forest do not seem to be attributable to reduced foliar palatability, suggesting that changes in the insect assemblage, and not palatability, account for reduced herbivory in fragmented forests.

  4. Vegetation, fire and climate change in central-east Isla Grande de Chiloé (43°S) since the Last Glacial Maximum, northwestern Patagonia

    NASA Astrophysics Data System (ADS)

    Pesce, O. H.; Moreno, P. I.

    2014-04-01

    We present a detailed record from Lago Lepué to examine vegetation, climate and fire-regime changes since the Last Glacial Maximum (LGM) in central-east Isla Grande de Chiloé (43°S), northwestern Patagonia. Precipitation in this region correlates with the intensity of the southern westerly winds (SWW), allowing reconstruction of past SWW behavior through precipitation-sensitive sensors. Recession from the LGM glacier margins exposed the central-east sector of Isla Grande de Chiloé by 17,800 cal yr BP, followed by the immediate colonization of pioneer cold-resistant herbs/shrubs and rapid establishment of closed-canopy Nothofagus forests by 17,000 cal yr BP. Broad-leaved temperate rainforests have persisted since then with compositional changes driven by changes in temperature, hydrologic balance and disturbance regimes. We detect low lake levels and enhanced fire activity between 800-2000, 4000-4300, ˜8000-11,000 and 16,100-17,800 cal yr BP, implying southward shifts and/or weaker SWW flow that alternated with cold, humid phases with muted fire activity. Covariation in paleoclimate trends revealed by the Lago Lepué record with tropical and Antarctic records since the LGM, suggests that the SWW have been a highly dynamic component of the climate system capable of linking climate changes from low- and high-southern latitudes during the Last Glacial termination and the current interglacial.

  5. New species of dictyostelids from Patagonia and Tierra del Fuego, Argentina.

    PubMed

    Vadell, Eduardo M; Cavender, James C; Romeralo, Maria; Edwards, Sally M; Stephenson, Steven L; Baldauf, Sandra L

    2011-01-01

    In late Jan and early Feb 2005 samples for isolation of dictyostelid cellular slime molds (dictyostelids) were collected in five different provinces and from six national parks (all located 39-55°S) in Patagonia and Tierra del Fuego, Argentina. Southern beech (Nothofagus) forests represented the primary vegetation type investigated, but some samples were obtained from Patagonian steppe, alpine meadows, Valdivian temperate rainforests and coniferous forests dominated by Araucaria, Austrocedrus and Fitzroya. Among the dictyostelids isolated from the samples we collected were seven species new to science. These species (Dictyostelium austroandinum, D. chordatum, D. fasciculoideum, D. gargantuum, D. leptosomopsis, D. valdivianum and Polysphondylium patagonicum) are described herein on the basis of both morphology and molecular (SSU rDNA) data. One of the new species, D. gargantuum, is one of the largest representatives of the group reported to date. Another unusual species, D. chordatum, produces long interwoven sorocarps that do not appear to respond to a spacing gas similar to the condition first noted in D. implicatum.

  6. Differential snow accumulation and melt at southern hemisphere deciduous forested sites

    NASA Astrophysics Data System (ADS)

    McPhee, James; Huerta, Marlene; Molotch, Noah

    2016-04-01

    Little is known about the differential snow dynamics resulting from forest cover in southern hemisphere alpine regions. Tree species variability and differences in local climate preclude extrapolation of northern hemisphere results and introduce uncertainty on the future impacts of climate change on snow-cover duration, maximum accumulation and melt rates. This research presents preliminary results from field observations obtained at an experimental watershed in the Nevados de Chillan region, in south-central Chile. The relatively low elevation of the Andes Cordillera and higher latitude of the site allows the existence of mixed Nothofagus forests, sometimes combined with bamboo-type undergrowth. Rain-on-snow events can be observed during winter and in the early stages of the austral spring. We installed four instrument clusters at the Valle Hermoso experimental catchments, where snow depth, air temperature and relative humidity were measured both under canopy and in forest clearings. The clusters where positioned in order to cover a range of elevations and sun exposure. Preliminary results from two winter seasons suggest that forest cover can impact accumulation rates as much as elevation does, and that melt rates are fairly sensitive to forest cover even in low LAI conditions.

  7. [Maternal factors associated with low birth weight].

    PubMed

    Heredia-Olivera, Karen; Munares-García, Oscar

    2016-01-01

    Introducción: En el Perú, el bajo peso al nacimiento es un indicador de riesgo de problemas perinatales y de la infancia, el objetivo del estudio fue determinar los factores maternos asociados al bajo peso al nacimiento. Métodos: Estudio de casos y controles, en 123 recién nacidos de bajo peso (casos) y 123 recién nacidos de peso normal (controles) pareados por fecha de nacimiento y distrito. Se indagaron factores maternos asociados al bajo peso al nacimiento y se comparó entre casos y controles. Se aplicó Chi cuadrada, Odds ratio (OR) con sus intervalos de confianza al 95% (IC 95%), regresión logística binaria y curva ROC. Resultados: Se encontraron asociaciones para antecedentes maternos de bajo peso (OR: 41.1; IC 95%: 5.5-306.7); prematuridad (OR: 12.0; IC 95%: 1.5-94.3), antecedente de eclampsia (OR: 5.8; IC 95%: 1.9-17.4), 1 a 3 controles prenatales (OR: 5.7; IC 95%: 2.6-12.3), gestación múltiple (OR: 4.7; IC 95%: 1.3-17.0) y consumo de tabaco (OR: 3.8; IC 95%: 1.5-9.8), el no ser adolescente (OR: 0.3; IC 95%: 0.1-0.6), y no tener un intervalo intergenésico corto (OR: 0.2; IC 95%: 0.1-0.7). El análisis multivariado nos indicó que el tener entre 1 a 3 controles prenatales, gestación múltiple, ser adolescente y un intervalo intergenésico corto se asocian al bajo peso al nacimiento, el modelo propuesto explicó el 18.6% del evento, el área bajo la curva fue 72.9% considerando que predice adecuadamente (p ˂ 0.001). Conclusiones: Existen factores de riesgo materno asociados al bajo peso al nacimiento en gestantes de zona urbana de la costa como el tener de 1 a 3 controles prenatales, gestación múltiple, ser adolescente y tener un periodo entre embarazos menor a dos años.

  8. Misión de operaciones en ambientes extremos

    NASA Video Gallery

    ¿En qué lugar del planeta se puede entrenar un astronauta en un entorno similar al espacio? ¿Qué les parece bajo el agua? NEEMO es un proyecto que envía a grupos de astronautas, ingenieros, médicos...

  9. Spawning aggregations of three protogynous groupers in the southern Gulf of Mexico.

    PubMed

    Tuz-Sulub, A; Brulé, T

    2015-01-01

    Spawning aggregations of red hind Epinephelus guttatus, tiger grouper Mycteroperca tigris and yellowfin grouper Mycteroperca venenosa were identified at two coral-reef systems: Arrecife Alacranes (emergent bank reef) and Bajos del Norte (submerged bank reef) on the continental shelf of the Yucatan Peninsula (Campeche Bank), Mexico. At both reefs, E. guttatus forms large spawning aggregations between February and March. At Bajos del Norte, M. tigris reproduces in a small, low-density aggregation in May, while M. venenosa aggregates at high densities for spawning between March and May. Multi-species use of an aggregation site by E. guttatus and M. venenosa was observed at Bajos del Norte. The identified spawning aggregations are apparently stable in location over time, and all three species were commonly observed to spawn within 1 week following the full moon. Development and survival of the larvae spawned in these aggregations are probably aided by a seasonal (spring-summer) upwelling in the north-east Campeche Bank. A permanent area closure at Bajos del Norte, currently outside any specific fisheries management area or regulations, would provide protection needed for the spawning aggregations of these three species.

  10. Algunas mujeres con cáncer de seno pueden abstenerse de quimioterapia

    Cancer.gov

    Resumen de resultados del estudio TAILORx indica que mujeres con cáncer de seno receptor de hormonas en estadio inicial tienen un riesgo bajo de recurrencia según una prueba de expresión de 21 genes.

  11. Spawning aggregations of three protogynous groupers in the southern Gulf of Mexico.

    PubMed

    Tuz-Sulub, A; Brulé, T

    2015-01-01

    Spawning aggregations of red hind Epinephelus guttatus, tiger grouper Mycteroperca tigris and yellowfin grouper Mycteroperca venenosa were identified at two coral-reef systems: Arrecife Alacranes (emergent bank reef) and Bajos del Norte (submerged bank reef) on the continental shelf of the Yucatan Peninsula (Campeche Bank), Mexico. At both reefs, E. guttatus forms large spawning aggregations between February and March. At Bajos del Norte, M. tigris reproduces in a small, low-density aggregation in May, while M. venenosa aggregates at high densities for spawning between March and May. Multi-species use of an aggregation site by E. guttatus and M. venenosa was observed at Bajos del Norte. The identified spawning aggregations are apparently stable in location over time, and all three species were commonly observed to spawn within 1 week following the full moon. Development and survival of the larvae spawned in these aggregations are probably aided by a seasonal (spring-summer) upwelling in the north-east Campeche Bank. A permanent area closure at Bajos del Norte, currently outside any specific fisheries management area or regulations, would provide protection needed for the spawning aggregations of these three species. PMID:25557429

  12. Estudio de NIH indica que la actividad física en tiempo libre alarga la vida tanto como 4,5 años

    Cancer.gov

    La actividad física en tiempo libre está asociada con una expectativa de vida más larga, aun en un grado de actividad relativamente bajo e independientemente del peso corporal, de acuerdo con un estudio llevado a cabo por un equipo de investigadores del I

  13. Centro para la Salud Mundial del NCI anuncia becas de investigación para tecnologías portátiles

    Cancer.gov

    El Centro para la Salud Mundial del NCI (CGH) anunció el otorgamiento de subvenciones que apoyarán el desarrollo y la validación de tecnologías portátiles y de bajo costo para mejorar la detección temprana, el diagnóstico y el tratamiento del cáncer.

  14. Añadir quimioterapia después de la radioterapia mejora la supervivencia de adultos con un tipo de tu

    Cancer.gov

    Adultos con gliomas de grado bajo, una forma de tumor cerebral, que recibieron tratamiento con quimioterapia después de la radioterapia vivieron más tiempo que pacientes que recibieron solo radioterapia, según los resultados de seguimiento a largo plazo d

  15. Effect of hospital nutrition support on growth velocity and nutritional status of low birth weight infants.

    PubMed

    Azzeh, Firas S; Alazzeh, Awfa Y; Dabbour, Ibrahim R; Jazar, Abdelelah S; Obeidat, Ahmed A

    2014-10-01

    Introducción: Los bebés con bajo peso al nacer reciben asistencia nutricional hospitalaria para reforzar su supervivencia y peso corporal. Sin embargo, cada hospital tiene su propia fórmula de asistencia nutricional. Por lo tanto, la efectividad de esta asistencia nutricional debería ser investigada. Objetivo: Evaluar el efecto de la asistencia nutricional hospitalaria sobre la velocidad del crecimiento velocidad del crecimiento y el estado nutricional de bebés con bajo peso al nacer en el hospital Al-Noor, Arabia Saudita. Métodos: Se llevó a cabo un estudio interseccional entre octubre de 2010 y diciembre de 2012. Se seleccionó a trescientos recién nacidos del hospital Al-Noor de la ciudad de Makkah, Arabia Saudita. Los bebés fueron seleccionados según su peso al nacer y fueron separados en tres grupos iguales: (i) Bajo peso al nacer (BPN) (peso de nacimiento 1501- 2500 g), (ii) Muy Bajo peso al nacer (MBPN) (peso de nacimiento 1001-1500 g) y (iii) Peso extremadamente bajo al nacer (PEBN) (peso de nacimiento < 1000 g). Los datos fueron recopilados en el momento del nacimiento y en el momento del alta. Los pesos fueron registrados y se calculó la velocidad del crecimiento. Se hizo la medición de algunos tests bioquímicos y niveles minerales. Resultados: los valores de índice de masa corporal del VBPN y EBPN fueron menores (p < 0.05) que los del grupo BPN. La velocidad de crecimiento de los niños de todos los grupos osciló entre 8.7 y 10.2 g/kg/d sin diferencias (p > 0.05) observadas entre grupos. Los niveles de suero, calcio, fósforo y potasio en el momento del alta fueron superiores (p < 0.05) que los del momento del nacimiento para los grupos de EBPN y VBPN, mientras que los niveles de sodio descendieron en el grupo de EBPN hasta un rango normal. El nivel de albúmina mejoró (p < 0.05) en el grupo de EBPN. Conclusión: La gestión de la atención sanitaria para bebés con bajo peso al nacer en el hospital Al-Noor no fue suficiente para alcanzar

  16. [SOCIODEMOGRAPHIC AND HEALTH CHARACTERISTICS ASSOCIATED WITH LOW BIRTH WEIGHT IN THE CANARY ISLANDS].

    PubMed

    Bello Lujan, Luis M; Saavedra Santana, Pedro; Gutiérrez García, Luisa Esther; García Hernández, José Angel; Serra Majem, Lluis

    2015-10-01

    Introducción y objetivo: desde 1976, el término bajo peso al nacer (BPN) se aplica a todos los recién nacidos con un peso inferior a 2.500 g. y constituye el factor más importante que afecta a la mortalidad neonatal y a la morbilidad en la infancia. El objetivo de este trabajo es identificar las asociaciones entre los factores biológicos, socioeconómicos y sanitarios y el bajo peso en el recién nacido en las islas Canarias. Material y método: se realizó un estudio epidemiológico transversal, con los ficheros de las gestantes del 2011 y 2012 (n = 11,768) del Complejo Hospitalario Universitario Insular Materno de Gran Canaria, que representó el 66,3% de todos los partos de la provincia para esos años, excluyéndose del análisis los datos correspondientes a los embarazos múltiples (393) (3,3%). Se analizaron la distribución y la frecuencia del peso según características sociodemográficas; los porcentajes se compararon con el test de la 2, las medias con el t-test y las medianas con el test de Wilcoxon para datos independientes. Aquellas variables que mostraron asociación con el bajo peso en el análisis univariado fueron introducidas en un análisis logístico multidimensional. Resultados: en la distribución del peso al nacer se observó un exceso de niños con bajo peso (9,3%), de los cuales el 62,1% fueron pretérmino. Las madres de estos niños son más delgadas, de menor talla y tienen un IMC promedio de < 18,5 kg/m2, así como un promedio de edad de 31,5 años. Se observó igualmente que existe un incremento entre la edad de la madre y el bajo peso, aunque el efecto no es lineal; de hecho, los aumentos del riesgo de BPN se aceleran a medida que aumenta la edad. Cuando el IMC de la madre decrece, aproximadamente por debajo de 25, aumenta linealmente el riesgo de bajo peso. Las OR más elevadas corresponden al retraso fetal en el crecimiento intrauterino (CIR) (OR = 6,3; IC-95% = 5,3; 7,4), la hipertensión/eclampsia (OR = 3,2; IC-95% = 2

  17. Ultraviolet Radiation Influences Perch Selection by a Neotropical Poison-Dart Frog

    PubMed Central

    Kats, Lee B.; Bucciarelli, Gary M.; Schlais, David E.; Blaustein, Andrew R.; Han, Barbara A.

    2012-01-01

    Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy. PMID:23251505

  18. Phenotypic screen for RNAi effects in the codling moth Cydia pomonella.

    PubMed

    Wang, Jinda; Gu, Liuqi; Ireland, Stephen; Garczynski, Stephen F; Knipple, Douglas C

    2015-11-10

    RNAi-based technologies have the potential to augment, or replace existing pest management strategies. However, some insect taxa are less susceptible to the induction of the post-transcriptional gene silencing effect than others, such as the Lepidoptera. Here we describe experiments to investigate the induction of RNAi in the codling moth, Cydia pomonella, a major lepidopteran pest of apple, pear, and walnut. Prior to a knockdown screen, fluorescently labeled small interfering RNA (siRNA) and double-stranded RNA (dsRNA) derived from green fluorescent protein (GFP) coding sequence were delivered to the surface of artificial diet to which neonate larvae were introduced and subsequently examined for the distribution of fluorescence in their tissues. Fluorescence was highly concentrated in the midgut but its presence in other tissues was equivocal. Next, dsRNAs were made for C. pomonella genes orthologous to those that have well defined deleterious phenotypes in Drosophila melanogaster. A screen was conducted using dsRNAs encoding cullin-1 (Cpcul1), maleless (Cpmle), musashi (Cpmsi), a homeobox gene (CpHbx), and pumilio (Cppum). The dsRNAs designed from these target genes were administered to neonate larvae by delivery to the surface of the growth medium. None of the dsRNA treatments affected larval viability, however Cpcul1-dsRNA had a significant effect on larval growth, with the average length of larvae about 3mm, compared to about 4mm in the control groups. Measurement of Cpcul1 transcript levels by quantitative real-time PCR (qRT-PCR) revealed a dose-dependent RNAi effect in response to increasing amount of Cpcul1-dsRNA. Despite their reduced size, Cpcul1-dsRNA-treated larvae molted normally and matured to adulthood in a manner similar to controls. In an additional experiment, Cpcul1-siRNA was found to induce similar stunting effect as that induced by Cpcul1-dsRNA. PMID:26162675

  19. Inferring predator behavior from attack rates on prey-replicas that differ in conspicuousness.

    PubMed

    Stuart, Yoel E; Dappen, Nathan; Losin, Neil

    2012-01-01

    Behavioral ecologists and evolutionary biologists have long studied how predators respond to prey items novel in color and pattern. Because a predatory response is influenced by both the predator's ability to detect the prey and a post-detection behavioral response, variation among prey types in conspicuousness may confound inference about post-prey-detection predator behavior. That is, a relatively high attack rate on a given prey type may result primarily from enhanced conspicuousness and not predators' direct preference for that prey. Few studies, however, account for such variation in conspicuousness. In a field experiment, we measured predation rates on clay replicas of two aposematic forms of the poison dart frog Dendrobates pumilio, one novel and one familiar, and two cryptic controls. To ask whether predators prefer or avoid a novel aposematic prey form independently of conspicuousness differences among replicas, we first modeled the visual system of a typical avian predator. Then, we used this model to estimate replica contrast against a leaf litter background to test whether variation in contrast alone could explain variation in predator attack rate. We found that absolute predation rates did not differ among color forms. Predation rates relative to conspicuousness did, however, deviate significantly from expectation, suggesting that predators do make post-detection decisions to avoid or attack a given prey type. The direction of this deviation from expectation, though, depended on assumptions we made about how avian predators discriminate objects from the visual background. Our results show that it is important to account for prey conspicuousness when investigating predator behavior and also that existing models of predator visual systems need to be refined. PMID:23119039

  20. Inferring Predator Behavior from Attack Rates on Prey-Replicas That Differ in Conspicuousness

    PubMed Central

    2012-01-01

    Behavioral ecologists and evolutionary biologists have long studied how predators respond to prey items novel in color and pattern. Because a predatory response is influenced by both the predator’s ability to detect the prey and a post-detection behavioral response, variation among prey types in conspicuousness may confound inference about post-prey-detection predator behavior. That is, a relatively high attack rate on a given prey type may result primarily from enhanced conspicuousness and not predators’ direct preference for that prey. Few studies, however, account for such variation in conspicuousness. In a field experiment, we measured predation rates on clay replicas of two aposematic forms of the poison dart frog Dendrobates pumilio, one novel and one familiar, and two cryptic controls. To ask whether predators prefer or avoid a novel aposematic prey form independently of conspicuousness differences among replicas, we first modeled the visual system of a typical avian predator. Then, we used this model to estimate replica contrast against a leaf litter background to test whether variation in contrast alone could explain variation in predator attack rate. We found that absolute predation rates did not differ among color forms. Predation rates relative to conspicuousness did, however, deviate significantly from expectation, suggesting that predators do make post-detection decisions to avoid or attack a given prey type. The direction of this deviation from expectation, though, depended on assumptions we made about how avian predators discriminate objects from the visual background. Our results show that it is important to account for prey conspicuousness when investigating predator behavior and also that existing models of predator visual systems need to be refined. PMID:23119039

  1. Development of Mitochondrial Loop-Mediated Isothermal Amplification for Detection of the Small Liver Fluke Opisthorchis viverrini (Opisthorchiidae; Trematoda; Platyhelminthes)

    PubMed Central

    Nguyen, Nga Thi Bich; Truong, Nam Hai; De, Nguyen Van

    2012-01-01

    Mitochondrial DNA sequences offer major advantages over the more usual nuclear targets for loop-mediated isothermal amplification approaches (mito-LAMP) because multiple copies occur in every cell. Four LAMP primers [F3, FIP(F1c+F2), BIP(B1c+B2), and B3] were designed based on the mitochondrial nad1 sequence of Opisthorchis viverrini and used for a highly specific assay (mito-OvLAMP) to distinguish DNA of O. viverrini from that of another opisthorchiid (Clonorchis sinensis) and other trematodes (Haplorchis pumilio, Haplorchis taichui, Fasciola hepatica, and Fasciola gigantica). Conventional PCR was applied using F3/B3 primer pairs to verify the specificity of the primers for O. viverrini DNA templates. All LAMP-positive samples could be detected with the naked eye in sunlight, by gel electrophoresis (stained with ethidium bromide), and by addition of SYBR green I to the product in sunlight or under UV light. Only DNA from O. viverrini yielded amplification products by LAMP (and by PCR verification), and the LAMP limit of detection was as little as 100 fg (10−4 ng DNA), indicating that this assay is 10 to 100 times more sensitive than PCR. Field testing was done using representative egg and metacercarial samples collected from localities where the fluke is endemic. With the advantages of simplicity, rapidity, sensitivity, and cost effectiveness, mito-OvLAMP is a good tool for molecular detection and epidemiology studies in regions or countries where O. viverrini is endemic, which can lead to more effective control of opisthorchiasis and trematodiasis. PMID:22322346

  2. The PUF binding landscape in metazoan germ cells

    PubMed Central

    Prasad, Aman; Porter, Douglas F.; Kroll-Conner, Peggy L.; Mohanty, Ipsita; Ryan, Anne R.; Crittenden, Sarah L.; Wickens, Marvin; Kimble, Judith

    2016-01-01

    PUF (Pumilio/FBF) proteins are RNA-binding proteins and conserved stem cell regulators. The Caenorhabditis elegans PUF proteins FBF-1 and FBF-2 (collectively FBF) regulate mRNAs in germ cells. Without FBF, adult germlines lose all stem cells. A major gap in our understanding of PUF proteins, including FBF, is a global view of their binding sites in their native context (i.e., their “binding landscape”). To understand the interactions underlying FBF function, we used iCLIP (individual-nucleotide resolution UV crosslinking and immunoprecipitation) to determine binding landscapes of C. elegans FBF-1 and FBF-2 in the germline tissue of intact animals. Multiple iCLIP peak-calling methods were compared to maximize identification of both established FBF binding sites and positive control target mRNAs in our iCLIP data. We discovered that FBF-1 and FBF-2 bind to RNAs through canonical as well as alternate motifs. We also analyzed crosslinking-induced mutations to map binding sites precisely and to identify key nucleotides that may be critical for FBF–RNA interactions. FBF-1 and FBF-2 can bind sites in the 5′UTR, coding region, or 3′UTR, but have a strong bias for the 3′ end of transcripts. FBF-1 and FBF-2 have strongly overlapping target profiles, including mRNAs and noncoding RNAs. From a statistically robust list of 1404 common FBF targets, 847 were previously unknown, 154 were related to cell cycle regulation, three were lincRNAs, and 335 were shared with the human PUF protein PUM2. PMID:27165521

  3. Ultraviolet radiation influences perch selection by a neotropical poison-dart frog.

    PubMed

    Kats, Lee B; Bucciarelli, Gary M; Schlais, David E; Blaustein, Andrew R; Han, Barbara A

    2012-01-01

    Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy. PMID:23251505

  4. Validation of endogenous control reference genes for normalizing gene expression studies in endometrial carcinoma.

    PubMed

    Ayakannu, Thangesweran; Taylor, Anthony H; Willets, Jonathon M; Brown, Laurence; Lambert, David G; McDonald, John; Davies, Quentin; Moss, Esther L; Konje, Justin C

    2015-09-01

    Real-time quantitative RT-PCR (qRT-PCR) is a powerful technique used for the relative quantification of target genes, using reference (housekeeping) genes for normalization to ensure the generation of accurate and robust data. A systematic examination of the suitability of endogenous reference genes for gene expression studies in endometrial cancer tissues is absent. The aims of this study were therefore to identify and evaluate from the thirty-two possible reference genes from a TaqMan(®) array panel their suitability as an internal control gene. The mathematical software packages geNorm qBasePLUS identified Pumilio homolog 1 (Drosophila) (PUM1), ubiquitin C (UBC), phosphoglycerate kinase (PGK1), mitochondrial ribosomal protein L19 (MRPL19) and peptidylpropyl isomerase A (cyclophilin A) (PPIA) as the best reference gene combination, whilst NormFinder identified MRPL19 as the best single reference gene, with importin 8 (IPO8) and PPIA being the best combination of two reference genes. BestKeeper ranked MRPL19 as the most stably expressed gene. In addition, the study was validated by examining the relative expression of a test gene, which encodes the cannabinoid receptor 1 (CB1). A significant difference in CB1 mRNA expression between malignant and normal endometrium using MRPL19, PPIA, and IP08 in combination was observed. The use of MRPL19, IPO8 and PPIA was identified as the best reference gene combination for the normalization of gene expression levels in endometrial carcinoma. This study demonstrates that the arbitrary selection of endogenous control reference genes for normalization in qRT-PCR studies of endometrial carcinoma, without validation, risks the production of inaccurate data and should therefore be discouraged.

  5. Minor Histocompatibility Antigens Are Expressed in Syncytiotrophoblast and Trophoblast Debris

    PubMed Central

    Holland, Olivia J.; Linscheid, Caitlin; Hodes, Herbert C.; Nauser, Traci L.; Gilliam, Melissa; Stone, Peter; Chamley, Larry W.; Petroff, Margaret G.

    2012-01-01

    The fetal semi-allograft can induce expansion and tolerance of antigen-specific maternal T and B cells through paternally inherited major histocompatibility complex and minor histocompatibility antigens (mHAgs). The effects of these antigens have important consequences on the maternal immune system both during and long after pregnancy. Herein, we investigate the possibility that the placental syncytiotrophoblast and deported trophoblastic debris serve as sources of fetal mHAgs. We mapped the expression of four mHAgs (human mHAg 1, pumilio domain-containing protein KIAA0020, B-cell lymphoma 2–related protein A1, and ribosomal protein S4, Y linked) in the placenta. Each of these proteins was expressed in several placental cell types, including the syncytiotrophoblast. These antigens and two additional Y chromosome–encoded antigens [DEAD box polypeptide 3, Y linked (DDX3Y), and lysine demethylase5D] were also identified by RT-PCR in the placenta, purified trophoblast cells, and cord blood cells. Finally, we used a proteomic approach to investigate the presence of mHAgs in the syncytiotrophoblast and trophoblast debris shed from first-trimester placenta. By this method, four antigens (DDX3Y; ribosomal protein S4, Y linked; solute carrier 1A5; and signal sequence receptor 1) were found in the syncytiotrophoblast, and one antigen (DDX3Y) was found in shed trophoblast debris. The finding of mHAgs in the placenta and in trophoblast debris provides the first direct evidence that fetal antigens are present in debris shed from the human placenta. The data, thus, suggest a mechanism by which the maternal immune system is exposed to fetal alloantigens, possibly explaining the relationship between parity and graft-versus-host disease. PMID:22079431

  6. Development of mitochondrial loop-mediated isothermal amplification for detection of the small liver fluke Opisthorchis viverrini (Opisthorchiidae; Trematoda; Platyhelminthes).

    PubMed

    Le, Thanh Hoa; Nguyen, Nga Thi Bich; Truong, Nam Hai; De, Nguyen Van

    2012-04-01

    Mitochondrial DNA sequences offer major advantages over the more usual nuclear targets for loop-mediated isothermal amplification approaches (mito-LAMP) because multiple copies occur in every cell. Four LAMP primers [F3, FIP(F1c+F2), BIP(B1c+B2), and B3] were designed based on the mitochondrial nad1 sequence of Opisthorchis viverrini and used for a highly specific assay (mito-OvLAMP) to distinguish DNA of O. viverrini from that of another opisthorchiid (Clonorchis sinensis) and other trematodes (Haplorchis pumilio, Haplorchis taichui, Fasciola hepatica, and Fasciola gigantica). Conventional PCR was applied using F3/B3 primer pairs to verify the specificity of the primers for O. viverrini DNA templates. All LAMP-positive samples could be detected with the naked eye in sunlight, by gel electrophoresis (stained with ethidium bromide), and by addition of SYBR green I to the product in sunlight or under UV light. Only DNA from O. viverrini yielded amplification products by LAMP (and by PCR verification), and the LAMP limit of detection was as little as 100 fg (10(-4) ng DNA), indicating that this assay is 10 to 100 times more sensitive than PCR. Field testing was done using representative egg and metacercarial samples collected from localities where the fluke is endemic. With the advantages of simplicity, rapidity, sensitivity, and cost effectiveness, mito-OvLAMP is a good tool for molecular detection and epidemiology studies in regions or countries where O. viverrini is endemic, which can lead to more effective control of opisthorchiasis and trematodiasis. PMID:22322346

  7. Infection Status of Zoonotic Trematode Metacercariae in Fishes from Vientiane Municipality and Champasak Province in Lao PDR

    PubMed Central

    Eom, Keeseon S.; Park, Han-Sol; Lee, Dongmin; Sohn, Woon-Mok; Yong, Tai-Soon; Chai, Jong-Yil; Min, Duk-Young; Rim, Han-Jong; Insisiengmay, Bounnaloth; Phommasack, Bounlay

    2015-01-01

    The infection status of fishborne zoonotic trematode (FZT) metacercariae was investigated in fishes from 2 localities of Lao PDR. Total 157 freshwater fishes (17 species) were collected in local markets of Vientiane Municipality and Champasak Province in December 2010 and July 2011, and each fish was examined by the artificial digestion method. Total 6 species of FZT metacercariae, i.e., Opisthorchis viverrini, Haplorchis taichui, Haplorchis yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium, were detected in fishes from Vientiane Municipality. The metacercariae of O. viverrini were detected in 50 (49.5%) out of 101 fishes (6 species), and their average number was 154 per fish infected. The remaining 5 species of heterophyid metacercariae were detected in 36.8%, 65.8%, 9.4%, 23.9%, and 5.1% fishes examined, and their average densities were 12, 1,038, 4, 15, and 13 per infected fish, respectively. In fishes from Champasak Province, 3 species of FZT metacercariae, i.e., O. viverrini, H. taichui, and H. yokogawai, were detected. Only 2 O. viverrini metacercariae were found in only 1 Barbonymus schwanefeldi. The metacercariae of H. taichui and H. yokogawai were detected in 60.0% and 50.0% of fishes examined, and their average densities were 47 and 28 per fish infected. By the present study, it has been confirmed that several species of FZT metacercariae are prevalent in fishes from Vientiane Municipality, with P. varium being a new member of FZT in Lao PDR. In comparison, FZT metacercariae are less prevalent in fishes from Champasak Province. PMID:26323843

  8. Prevalence and intensity of fish-borne zoonotic trematodes in cultured freshwater fish from rural and urban areas of northern Vietnam.

    PubMed

    Van De, Nguyen; Le, Thanh Hoa; Murrell, K D

    2012-10-01

    Consumption of raw freshwater fish produced in both rural farm and urban wastewater ponds is a common practice in Vietnam. The present study assessed the risk of fish-borne zoonotic trematode (FZT) infection from fish raised in both these aquaculture systems in northern Vietnam. The diversity, prevalence, and infection intensity of FZT metacercariae in 1,500 freshwater fish collected from 6 sites located in rural and urban areas in northern Vietnam were investigated. The specific diagnosis of species was made by morphologic methods. The overall FZT prevalence in fish from both urban wastewater ponds and rural farm ponds was 11.2%. In wastewater ponds, the overall prevalence was 5.1%, ranging from 2.0% in tilapia to 7.3% in common and grass carp. In fish from farm ponds, the prevalence was 17.3%, and ranged from 6.7% in mud carp to 26.7% in common carp. The mean intensity of FZT infection was also higher in fish from farm ponds than that in fish from wastewater ponds (6.0% and 8.4%, respectively). The FZT species recovered from infected fish included both liver (Clonorchis sinensis) and intestinal flukes (Haplorchis taichui, Haplorchis pumilio, and Centrocestus formosanus). The prevalence of FZT in fish raised in these common farm systems represents a significant public health risk for a population with a strong cultural preference for consuming raw or inadequately prepared fish. These research results should encourage the public health and agriculture sectors to conduct the risk factor research required to develop control programs for FZT.

  9. Development of mitochondrial loop-mediated isothermal amplification for detection of the small liver fluke Opisthorchis viverrini (Opisthorchiidae; Trematoda; Platyhelminthes).

    PubMed

    Le, Thanh Hoa; Nguyen, Nga Thi Bich; Truong, Nam Hai; De, Nguyen Van

    2012-04-01

    Mitochondrial DNA sequences offer major advantages over the more usual nuclear targets for loop-mediated isothermal amplification approaches (mito-LAMP) because multiple copies occur in every cell. Four LAMP primers [F3, FIP(F1c+F2), BIP(B1c+B2), and B3] were designed based on the mitochondrial nad1 sequence of Opisthorchis viverrini and used for a highly specific assay (mito-OvLAMP) to distinguish DNA of O. viverrini from that of another opisthorchiid (Clonorchis sinensis) and other trematodes (Haplorchis pumilio, Haplorchis taichui, Fasciola hepatica, and Fasciola gigantica). Conventional PCR was applied using F3/B3 primer pairs to verify the specificity of the primers for O. viverrini DNA templates. All LAMP-positive samples could be detected with the naked eye in sunlight, by gel electrophoresis (stained with ethidium bromide), and by addition of SYBR green I to the product in sunlight or under UV light. Only DNA from O. viverrini yielded amplification products by LAMP (and by PCR verification), and the LAMP limit of detection was as little as 100 fg (10(-4) ng DNA), indicating that this assay is 10 to 100 times more sensitive than PCR. Field testing was done using representative egg and metacercarial samples collected from localities where the fluke is endemic. With the advantages of simplicity, rapidity, sensitivity, and cost effectiveness, mito-OvLAMP is a good tool for molecular detection and epidemiology studies in regions or countries where O. viverrini is endemic, which can lead to more effective control of opisthorchiasis and trematodiasis.

  10. Fish-borne trematodes in cultured Nile tilapia (Oreochromis niloticus) and wild-caught fish from Thailand.

    PubMed

    Wiriya, Benjamaporn; Clausen, Jesper Hedegaard; Inpankaew, Tawin; Thaenkham, Urusa; Jittapalapong, Sathaporn; Satapornvanit, Kriengkrai; Dalsgaard, Anders

    2013-11-15

    Fish-borne zoonotic trematode (FZT) infections affect the health of more than 18 million people around the world, particularly in Asian countries. Nile tilapia (Oreochromis niloticus) is a white meat fish that has an increasing national and international market. The objective of this study was to determine the prevalence of FZT metacercarial infections in Nile tilapia from cage and pond aquaculture systems and in wild-caught fish from Suphan Buri, Nakhon Pathom and Chachoengsao provinces, Thailand. Fish were collected from four cages in Suphan Buri and four ponds in Nakhon Pathom provinces between September-October 2011 and April-May 2012 and wild-caught fish were collected in May 2012. All fish were examined for metacercariae by a pepsin digestion and metacercariae identified using morphological and molecular methods. During the first sampling of tilapia the prevalence of metacercariae in cage culture fish were 2.5% and 10% in pond culture fish. During the second sampling, metacercariae was found in 2.0% of tilapia from cage and none from the ponds. Of the 150 wild-caught fish, a total of 80 (53.3%) were found to be infected with metacercariae, mostly the zoonotic species Stellantchasmus falcatus, Haplorchis pumilio and Procerovum varium. The results revealed a low risk for FZT in Nile tilapia cultured in cage and pond aquaculture systems. However, the high prevalence of FZT in wild-caught fish indicates a high potential for spillover from wild reservoir hosts and underscores the need for vigilance and good management practices by the aquaculture sector.

  11. Ultraviolet radiation influences perch selection by a neotropical poison-dart frog.

    PubMed

    Kats, Lee B; Bucciarelli, Gary M; Schlais, David E; Blaustein, Andrew R; Han, Barbara A

    2012-01-01

    Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy.

  12. Phenotypic screen for RNAi effects in the codling moth Cydia pomonella.

    PubMed

    Wang, Jinda; Gu, Liuqi; Ireland, Stephen; Garczynski, Stephen F; Knipple, Douglas C

    2015-11-10

    RNAi-based technologies have the potential to augment, or replace existing pest management strategies. However, some insect taxa are less susceptible to the induction of the post-transcriptional gene silencing effect than others, such as the Lepidoptera. Here we describe experiments to investigate the induction of RNAi in the codling moth, Cydia pomonella, a major lepidopteran pest of apple, pear, and walnut. Prior to a knockdown screen, fluorescently labeled small interfering RNA (siRNA) and double-stranded RNA (dsRNA) derived from green fluorescent protein (GFP) coding sequence were delivered to the surface of artificial diet to which neonate larvae were introduced and subsequently examined for the distribution of fluorescence in their tissues. Fluorescence was highly concentrated in the midgut but its presence in other tissues was equivocal. Next, dsRNAs were made for C. pomonella genes orthologous to those that have well defined deleterious phenotypes in Drosophila melanogaster. A screen was conducted using dsRNAs encoding cullin-1 (Cpcul1), maleless (Cpmle), musashi (Cpmsi), a homeobox gene (CpHbx), and pumilio (Cppum). The dsRNAs designed from these target genes were administered to neonate larvae by delivery to the surface of the growth medium. None of the dsRNA treatments affected larval viability, however Cpcul1-dsRNA had a significant effect on larval growth, with the average length of larvae about 3mm, compared to about 4mm in the control groups. Measurement of Cpcul1 transcript levels by quantitative real-time PCR (qRT-PCR) revealed a dose-dependent RNAi effect in response to increasing amount of Cpcul1-dsRNA. Despite their reduced size, Cpcul1-dsRNA-treated larvae molted normally and matured to adulthood in a manner similar to controls. In an additional experiment, Cpcul1-siRNA was found to induce similar stunting effect as that induced by Cpcul1-dsRNA.

  13. Evidence for Novel Hepaciviruses in Rodents

    PubMed Central

    Drexler, Jan Felix; Corman, Victor Max; Müller, Marcel Alexander; Lukashev, Alexander N.; Gmyl, Anatoly; Coutard, Bruno; Adam, Alexander; Ritz, Daniel; Leijten, Lonneke M.; van Riel, Debby; Kallies, Rene; Klose, Stefan M.; Gloza-Rausch, Florian; Binger, Tabea; Annan, Augustina; Adu-Sarkodie, Yaw; Oppong, Samuel; Bourgarel, Mathieu; Rupp, Daniel; Hoffmann, Bernd; Schlegel, Mathias; Kümmerer, Beate M.; Krüger, Detlev H.; Schmidt-Chanasit, Jonas; Setién, Alvaro Aguilar; Cottontail, Veronika M.; Hemachudha, Thiravat; Wacharapluesadee, Supaporn; Osterrieder, Klaus; Bartenschlager, Ralf; Matthee, Sonja; Beer, Martin; Kuiken, Thijs; Reusken, Chantal; Leroy, Eric M.; Ulrich, Rainer G.; Drosten, Christian

    2013-01-01

    Hepatitis C virus (HCV) is among the most relevant causes of liver cirrhosis and hepatocellular carcinoma. Research is complicated by a lack of accessible small animal models. The systematic investigation of viruses of small mammals could guide efforts to establish such models, while providing insight into viral evolutionary biology. We have assembled the so-far largest collection of small-mammal samples from around the world, qualified to be screened for bloodborne viruses, including sera and organs from 4,770 rodents (41 species); and sera from 2,939 bats (51 species). Three highly divergent rodent hepacivirus clades were detected in 27 (1.8%) of 1,465 European bank voles (Myodes glareolus) and 10 (1.9%) of 518 South African four-striped mice (Rhabdomys pumilio). Bats showed anti-HCV immunoblot reactivities but no virus detection, although the genetic relatedness suggested by the serologic results should have enabled RNA detection using the broadly reactive PCR assays developed for this study. 210 horses and 858 cats and dogs were tested, yielding further horse-associated hepaciviruses but none in dogs or cats. The rodent viruses were equidistant to HCV, exceeding by far the diversity of HCV and the canine/equine hepaciviruses taken together. Five full genomes were sequenced, representing all viral lineages. Salient genome features and distance criteria supported classification of all viruses as hepaciviruses. Quantitative RT-PCR, RNA in-situ hybridisation, and histopathology suggested hepatic tropism with liver inflammation resembling hepatitis C. Recombinant serology for two distinct hepacivirus lineages in 97 bank voles identified seroprevalence rates of 8.3 and 12.4%, respectively. Antibodies in bank vole sera neither cross-reacted with HCV, nor the heterologous bank vole hepacivirus. Co-occurrence of RNA and antibodies was found in 3 of 57 PCR-positive bank vole sera (5.3%). Our data enable new hypotheses regarding HCV evolution and encourage efforts to

  14. Adaptation for rodent pollination in Leucospermum arenarium (Proteaceae) despite rapid pollen loss during grooming

    PubMed Central

    Johnson, Christopher Michael; Pauw, Anton

    2014-01-01

    Background and Aims Plants are adapted for rodent pollination in diverse and intricate ways. This study explores an extraordinary example of these adaptations in the pincushion Leucospermum arenarium (Proteaceae) from South Africa. Methods Live trapping and differential exclusion experiments were used to test the role of rodents versus birds and insects as pollinators. To explore the adaptive significance of geoflory, inflorescences were raised above ground level and seed production was compared. Captive rodents and flowers with artificial stigmas were used to test the effect of grooming on the rate of pollen loss. Microscopy, nectar composition analysis and manipulative experiments were used to investigate the bizarre nectar production and transport system. Key Results Differential exclusion of rodents, birds and insects demonstrated the importance of rodents in promoting seed production. Live trapping revealed that hairy-footed gerbils, Gerbillurus paeba, and striped field mice, Rhabdomys pumilio, both carried L. arenarium pollen on their forehead and rostrum, but much larger quantities ended up in faeces as a result of grooming. Terrarium experiments showed that grooming exponentially diminished the pollen loads that they carried. The nectar of L. arenarium was found to be unusually viscous and to be presented in a novel location on the petal tips, where rodents could access it without destroying the flowers. Nectar was produced inside the perianth, but was translocated to the petal tips via capillary ducts. In common with many other rodent-pollinated plants, the flowers are presented at ground level, but when raised to higher positions seed production was not reduced, indicating that selection through female function does not drive the evolution of geoflory. Conclusions Despite the apparent cost of pollen lost to grooming, L. arenarium has evolved remarkable adaptations for rodent pollination and provides the first case of this pollination system in the genus

  15. Fishborne zoonotic trematodes in raw fish dishes served in restaurants in Nam Dinh Province and Hanoi, Vietnam.

    PubMed

    Tran, Thi Kim Chi; Murrell, K Darwin; Madsen, Henry; Nguyen, Viet Khue; Dalsgaard, Anders

    2009-11-01

    Fishborne zoonotic trematode (FZT) parasites are a serious food safety problem in Asian countries because of their tradition of eating raw fish. In northern Vietnam, the prevalence of FZT metacercariae (MC) in wild-caught and cultured fish is quite high. The objective of this study was to assess the risk for acquiring these parasites from raw fish dishes prepared in restaurants. Samples of fish meat (body muscle) and remainder parts (head, gills, fins, skin, and muscle tissue from the tail) were obtained from 39 restaurants located in Nam Dinh province, an area endemic for FZTs, and from 74 restaurants in the capital city of Hanoi. Six species of zoonotic intestinal trematodes were recovered from a total of nine freshwater and brackish water fish species. Overall, the prevalence of MC in meat samples was 6.1% and in remainder samples, 34.9%; freshwater fish were more often infected (39.4%) than brackish water species (16.0%). Dishes from Nam Dinh restaurants were more often infected (11.8%) than those from Hanoi (3.1%). The dominant trematode species, Haplorchis pumilio, exhibited a strong predilection for encystment in remainder fish parts (36.5%) compared with meat (3.9%). The mean density of MC in meat samples overall was low (1.0 to 1.5 MC per 50 g); however, the potential for parasites to accumulate over years of eating raw fish could result in significant clinical disease, as occurs with liver flukes. Also, the high densities of MC in the remainder parts (2.3 to 72.9 MC per 50 g) pose a threat for cross-contamination during dish preparation. PMID:19903407

  16. Can ectomycorrhizal symbiosis and belowground plant traits be used as ecological tools to mitigate erosion on degraded slopes in the ultramafic soils of New Caledonia?

    NASA Astrophysics Data System (ADS)

    Demenois, Julien; Carriconde, Fabian; Rey, Freddy; Stokes, Alexia

    2015-04-01

    forest with dominance of Arillastrum gummiferum, dense humid forest with dominance of Nothofagus aequilateralis, and finally mixed dense humid forest. These types of vegetation are widely represented on ultramafic soils of New Caledonia and are likely to correspond to different successional phases. At the scale of species, dominant species in the above-mentioned types of vegetation are considered for herbaceous, shrubs and trees strata. Root traits of Costularia nervosa, Tristaniopsis glauca, Nothofagus aequilateralis and Arillastrum gummiferum are then characterized in situ. These species are of particular interest for post-mining ecological restoration in New Caledonia as they are light-tolerant, endemic, associated with ECM (except for Costularia nervosa) and of particular interest or already used by mining operators for post-mining ecological restoration. For both scales (community and species), soil characteristics will be collected. Very fine and fine roots, mean root diameter, root diameter diversity, root mass density, root length density, and specific root length will be considered. Degree of ectomycorrhization and fungal biomass through qPCR will be determined. Soil aggregate stability will be measured according to the standardized method NF X 31-515. Besides, greenhouse trials with Costularia nervosa, Tristaniopsis glauca and Arillastrum gummiferum are carried out to assess the influence of plant root traits, fungal inoculation and soil aggregate stability. Controlled plant inoculations are performed using available pure fungal strains isolated from New Caledonian ultramafic soils. Plants have been bred on sterilized soil samples from the field sites. Through this study, we target to identify associations between ECM fungi and plant species that could mitigate the erodibility of degraded ultramafic soils and then water erosion. A better knowledge of interactions between soil aggregate stability, ECM fungi and plant root traits is then expected to answer the

  17. Antarctic Miocene Climate

    NASA Astrophysics Data System (ADS)

    Ashworth, A. C.; Lewis, A. R.

    2013-12-01

    Fossils from Antarctic Miocene terrestrial deposits, coupled with stratigraphic, geochemical and paleontological data from marine boreholes, provide new insights into the climatic history of the continent. During the Miocene, ice caps coalesced to form ice sheets and vegetated surfaces gave way to barren expanses. The cryospheric changes especially have global climatic implications. The fossil data consists of diatoms, pollen and spores, and macroscopic remains of plants, ostracods, insects, molluscs and a fish. Plant fossils include wood and leaves of Nothofagus (southern beech), seeds of several vascular plants, including Ranunculus (buttercup), Hippuris (mare's-tail) and Myriophyllum (watermilfoil), megaspores of Isoetes (quillwort), and moss species. The insect chitin consists of larval head capsules of Chironomidae (midges) and exoskeletal parts of Coleoptera (beetles). The molluscs include freshwater gastropods and bivalves. The majority of these taxa are likely descendants of taxa that had survived on the continent from the Paleogene or earlier. Even though early Miocene glaciations may have been large, the climate was never cold enough to cause the extinction of the biota, which probably survived in coastal refugia. Early Miocene (c. 20 Ma) macrofossils from the McMurdo Dry Valleys (77°S) support palynological interpretations from the Cape Roberts and ANDRILL marine records that the upland vegetation was a shrub tundra. Mean summer temperature (MST) in the uplands was c. 6°C and possibly higher at the coast. The climate was wet, supporting mires and lakes. By the mid-Miocene, even though the climate continued to be wet. MST was c. 4°C which was too cold to support Nothofagus and most vascular plant species. Stratigraphic evidence indicates that the time between the Early and Mid-Miocene was a time of repeated ice advances and retreats of small glaciers originating from ice caps. At c. 14 Ma there appears to have been a modal shift in climate to

  18. Can ectomycorrhizal symbiosis and belowground plant traits be used as ecological tools to mitigate erosion on degraded slopes in the ultramafic soils of New Caledonia?

    NASA Astrophysics Data System (ADS)

    Demenois, Julien; Carriconde, Fabian; Rey, Freddy; Stokes, Alexia

    2015-04-01

    forest with dominance of Arillastrum gummiferum, dense humid forest with dominance of Nothofagus aequilateralis, and finally mixed dense humid forest. These types of vegetation are widely represented on ultramafic soils of New Caledonia and are likely to correspond to different successional phases. At the scale of species, dominant species in the above-mentioned types of vegetation are considered for herbaceous, shrubs and trees strata. Root traits of Costularia nervosa, Tristaniopsis glauca, Nothofagus aequilateralis and Arillastrum gummiferum are then characterized in situ. These species are of particular interest for post-mining ecological restoration in New Caledonia as they are light-tolerant, endemic, associated with ECM (except for Costularia nervosa) and of particular interest or already used by mining operators for post-mining ecological restoration. For both scales (community and species), soil characteristics will be collected. Very fine and fine roots, mean root diameter, root diameter diversity, root mass density, root length density, and specific root length will be considered. Degree of ectomycorrhization and fungal biomass through qPCR will be determined. Soil aggregate stability will be measured according to the standardized method NF X 31-515. Besides, greenhouse trials with Costularia nervosa, Tristaniopsis glauca and Arillastrum gummiferum are carried out to assess the influence of plant root traits, fungal inoculation and soil aggregate stability. Controlled plant inoculations are performed using available pure fungal strains isolated from New Caledonian ultramafic soils. Plants have been bred on sterilized soil samples from the field sites. Through this study, we target to identify associations between ECM fungi and plant species that could mitigate the erodibility of degraded ultramafic soils and then water erosion. A better knowledge of interactions between soil aggregate stability, ECM fungi and plant root traits is then expected to answer the

  19. High-Resolution Coproecology: Using Coprolites to Reconstruct the Habits and Habitats of New Zealand’s Extinct Upland Moa (Megalapteryx didinus)

    PubMed Central

    Wood, Jamie R.; Wilmshurst, Janet M.; Wagstaff, Steven J.; Worthy, Trevor H.; Rawlence, Nicolas J.; Cooper, Alan

    2012-01-01

    Knowledge about the diet and ecology of extinct herbivores has important implications for understanding the evolution of plant defence structures, establishing the influences of herbivory on past plant community structure and composition, and identifying pollination and seed dispersal syndromes. The flightless ratite moa (Aves: Dinornithiformes) were New Zealand’s largest herbivores prior to their extinction soon after initial human settlement. Here we contribute to the knowledge of moa diet and ecology by reporting the results of a multidisciplinary study of 35 coprolites from a subalpine cave (Euphrates Cave) on the South Island of New Zealand. Ancient DNA analysis and radiocarbon dating revealed the coprolites were deposited by the extinct upland moa (Megalapteryx didinus), and span from at least 6,368±31 until 694±30 14C years BP; the approximate time of their extinction. Using pollen, plant macrofossil, and ancient DNA analyses, we identified at least 67 plant taxa from the coprolites, including the first evidence that moa fed on the nectar-rich flowers of New Zealand flax (Phormium) and tree fuchsia (Fuchsia excorticata). The plant assemblage from the coprolites reflects a highly-generalist feeding ecology for upland moa, including browsing and grazing across the full range of locally available habitats (spanning southern beech (Nothofagus) forest to tussock (Chionochloa) grassland). Intact seeds in the coprolites indicate that upland moa may have been important dispersal agents for several plant taxa. Plant taxa with putative anti-browse adaptations were also identified in the coprolites. Clusters of coprolites (based on pollen assemblages, moa haplotypes, and radiocarbon dates), probably reflect specimens deposited at the same time by individual birds, and reveal the necessity of suitably large sample sizes in coprolite studies to overcome potential biases in diet interpretation. PMID:22768206

  20. Vegetation changes and their climatic implication for the late Pleistocene at Lake Poukawa, Hawkes Bay, New Zealand

    NASA Astrophysics Data System (ADS)

    Okuda, M.; Shulmeister, J.; Flenley, J. R.

    2002-07-01

    A detailed vegetation history extending back to the Last Interglacial (Marine Isotope Substage 5e) is presented for Lake Poukawa, Hawkes Bay, New Zealand. This history is based on palynological analyses of a 198-m core record, age secured by uranium/thorium (U/Th) and optically stimulated luminescence (OSL) dates as well as tephrochronology. Vegetation of the penultimate glacial (Isotope Stage 6) probably consisted of a very sparse shrubby herbland of stunted podocarps ( Phyllocladus sp.), daisies, grasses and sedges. Similar floras existed in each of the succeeding cool periods. Four interglacial/interstadial floras are preserved. The peak of the Last Interglacial (Substage 5e) was dominated by extensive lowland forest of tall forest podocarps ( Podocarpus/Prumnopitys), most probably matai ( Prumnopitys taxifolia) with red beech ( Nothofagus fusca), secondary forest trees ( Coprosma spp., Myrsine spp.) and tree ferns ( Cyathea spp.). In the Poukawa basin itself, a swamp forest of the podocarp ( Dacrycarpus dacrydioides) with the true palm ( Rhopalostylis sapida) expanded. Substage 5e was significantly warmer and/or moister than the present day. Substage 5c/5a was marked by montane forest of red and silver beeches ( N. fusca and N. menziesii), Phyllocladus spp. and secondary trees. A reduced representation of Podocarpus/ Prumnopitys possibly consists of montane podocarp ( Podocarpus hallii). We infer the temperature of Substage 5c/5a to have been 3.5-5 °C lower than the present day. Although Stage 3 flora are superficially similar to those of Substage 5c/5a, the beeches are relatively less dominant. The regional flora during Stage 1 is very similar to those of Substage 5e, but the density is lower with no swamp forest during the present interglaciation. This may represent a change in evapotranspiration balance around Poukawa, but may also be controlled by hydrological conditions within the basin.

  1. Low but structured chloroplast diversity in Atherosperma moschatum (Atherospermataceae) suggests bottlenecks in response to the Pleistocene glacials

    PubMed Central

    Worth, James R. P.; Marthick, James R.; Jordan, Gregory J.; Vaillancourt, René E.

    2011-01-01

    Background and Aims The cool temperate rainforests of Australia were much reduced in range during the cold and dry glacial periods, although genetic evidence indicates that two key rainforest species, Nothofagus cunninghamii and Tasmannia lanceolata, survived within multiple locations and underwent only local range expansions at the end of the Last Glacial. To better understand the glacial response of a co-occurring but wind-dispersed and less cold-tolerant rainforest tree species, Atherosperma moschatum, a chloroplast phylogeographic study was undertaken. Methods A total of 3294 bp of chloroplast DNA sequence was obtained for 155 samples collected from across the species' range. Key Results The distribution of six haplotypes observed in A. moschatum was geographically structured with an inferred ancestral haplotype restricted to Tasmania, while three non-overlapping and endemic haplotypes were found on the mainland of south-eastern Australia. Last glacial refugia for A. moschatum are likely to have occurred in at least one location in western Tasmania and in Victoria and within at least two locations in the Great Dividing Range of New South Wales. Nucleotide diversity of A. moschatum was lower (π = 0·00021) than either N. cunninghamii (0·00101) or T. lanceolata (0·00073), and was amongst the lowest recorded for any tree species. Conclusions This study provides evidence for past bottlenecks having impacted the chloroplast diversity of A. moschatum as a result of the species narrower climatic niche during glacials. This hypothesis is supported by the star-like haplotype network and similar estimated rates of chloroplast DNA substitution for A. moschatum and the two more cold tolerant and co-occurring species that have higher chloroplast diversity, N. cunninghamii and T. lanceolata. PMID:21856633

  2. High-resolution coproecology: using coprolites to reconstruct the habits and habitats of New Zealand's extinct upland moa (Megalapteryx didinus).

    PubMed

    Wood, Jamie R; Wilmshurst, Janet M; Wagstaff, Steven J; Worthy, Trevor H; Rawlence, Nicolas J; Cooper, Alan

    2012-01-01

    Knowledge about the diet and ecology of extinct herbivores has important implications for understanding the evolution of plant defence structures, establishing the influences of herbivory on past plant community structure and composition, and identifying pollination and seed dispersal syndromes. The flightless ratite moa (Aves: Dinornithiformes) were New Zealand's largest herbivores prior to their extinction soon after initial human settlement. Here we contribute to the knowledge of moa diet and ecology by reporting the results of a multidisciplinary study of 35 coprolites from a subalpine cave (Euphrates Cave) on the South Island of New Zealand. Ancient DNA analysis and radiocarbon dating revealed the coprolites were deposited by the extinct upland moa (Megalapteryx didinus), and span from at least 6,368±31 until 694±30 (14)C years BP; the approximate time of their extinction. Using pollen, plant macrofossil, and ancient DNA analyses, we identified at least 67 plant taxa from the coprolites, including the first evidence that moa fed on the nectar-rich flowers of New Zealand flax (Phormium) and tree fuchsia (Fuchsia excorticata). The plant assemblage from the coprolites reflects a highly-generalist feeding ecology for upland moa, including browsing and grazing across the full range of locally available habitats (spanning southern beech (Nothofagus) forest to tussock (Chionochloa) grassland). Intact seeds in the coprolites indicate that upland moa may have been important dispersal agents for several plant taxa. Plant taxa with putative anti-browse adaptations were also identified in the coprolites. Clusters of coprolites (based on pollen assemblages, moa haplotypes, and radiocarbon dates), probably reflect specimens deposited at the same time by individual birds, and reveal the necessity of suitably large sample sizes in coprolite studies to overcome potential biases in diet interpretation.

  3. Succession of Ground-Dwelling Beetle Assemblages After Fire in Three Habitat Types in the Andean Forest of NW Patagonia, Argentina

    PubMed Central

    Sasal, Yamila; Raffaele, Estela; Farji-Brener, Alejandro G.

    2010-01-01

    Wildfires are one of the major disturbances in the dynamics of forests and shrublands. However, little is known about their effects on insect communities that contribute to faunal biodiversity and play key roles in the ecosystem's dynamics. An intense and widespread fire occurred in 1999 in the Nahuel Huapi National Park in the Andean forest in northern Patagonia, Argentina. This fire affected adjacent, but different, habitat types. After the fire, beetle abundance, species richness and assemblage composition were compared among three habitats that were structurally different before the fire. These habitats were: 1) evergreen forest dominated by Nothofagus dombeyi (Mirb.) Oerst. (Fagales: Nothofagaceae), 2) a mixed forest of the evergreen conifer Austrocedrus chilensis (D. Don) Pic. Serm. and Bizzarri (Pinales: Cupressaceae) and N. dombeyi and 3) a shrubland with a diverse community of shrub species. The relationship between beetle diversity and vegetation structure was investigated over three consecutive years. Ground beetles were collected by pitfall traps, and plant species richness, vegetation cover, and height were measured. Beetle communities varied more over years between habitats during the early regeneration after fire. There was a shift in beetle assemblage composition with time after the fire in all habitat types, probably due to similar colonization rates and microclimatic conditions. Therefore, beetle succession was more influenced by recolonization and survivorship, accompanied by climatic conditions and recovery rate of plant communities over time, than it was influenced by pre-fire habitat conditions. These results suggest that in NW Patagonia, wildfire can have a substantial, short-term impact on beetle abundance and species composition. The pre-fire conditions of each habitat type determined the structure of post-fire communities of plants but not beetle assemblages. Wildfires produce simplification and homogenization of habitat types, and this

  4. Top-down and bottom-up processes in grassland and forested streams.

    PubMed

    Nyström, Per; McIntosh, Angus R; Winterbourn, Michael J

    2003-08-01

    The influence of predatory fish on the structure of stream food webs may be altered by the presence of forest canopy cover, and consequent differences in allochthonous inputs and primary production. Eight sites containing introduced brown trout ( Salmo trutta) and eight sites that did not were sampled in the Cass region, South Island, New Zealand. For each predator category, half the sites were located in southern beech (Nothofagus) forest patches (range of canopy cover, 65-90%) and the other half were in tussock grassland. Food resources used by two dominant herbivores-detritivores were assessed using stable isotopes. (13)C/(12)C ratios were obtained for coarse particulate organic matter (CPOM), fine particulate organic matter (FPOM), algal dominated biofilm from rocks, and larvae of Deleatidium (Ephemeroptera) and Olinga (Trichoptera). Total abundance and biomass of macroinvertebrates did not differ between streams with and without trout, but were significantly higher at grassland sites than forested sites. However, taxon richness and species composition differed substantially between trout and no-trout sites, irrespective of whether streams were located in forest or not. Trout streams typically contained more taxa, had low biomass of predatory invertebrates and large shredders, but a high proportion of consumers with cases or shells. The standing stock of CPOM was higher at forested sites, but there was less FPOM and more algae at sites with trout, regardless of the presence or absence of forest cover. The stable carbon isotope range for biofilm on rocks was broad and encompassed the narrow CPOM and FPOM ranges. At trout sites, carbon isotope ratios of Deleatidium, the most abundant invertebrate primary consumer, were closely related to biofilm values, but no relationship was found at no-trout sites where algal biomass was much lower. These results support a role for both bottom-up and top-down processes in controlling the structure of the stream communities

  5. Genetics of sprouting: effects of long-term persistence in fire-prone ecosystems.

    PubMed

    Premoli, Andrea C; Steinke, Lina

    2008-09-01

    Fire functional traits (postfire resprouting and seeding) are considered to be adaptations for persisting in fire-prone environments. Although ecological and evolutionary consequences of sprouting have been extensively discussed, within-species genetic variability and structure are unknown. Here we report levels and distribution patterns of genetic polymorphisms in postfire stands of the predominant sprouter Nothofagus antarctica. Fresh foliage of 50 individuals was collected following a spatially explicit sampling design for isozyme analysis from two replicates of each of four habitat types inhabited by the species in northwestern Patagonia, Argentina: matorral, high elevation, forest, and temporally flooded basins. Average polymorphism per population ranged from 44% to 78% and mean gene diversity per site H(S )varied from 0.187 to 0.274. These results show that sprouter populations hold considerable genetic variation. Significant genetic structure over short distances (< 50 m) was found at all locations. Ancient fine-scale genetic structure is preserved by occasional seedling establishment that results in high co-ancestry coefficients. Sprouter populations growing in suboptimal habitats such as matorral, high elevation or basins consist of pairs of heterozygous genets that occur at larger spatial scales as a result of micro-environmental heterogeneity and/or local competition between near neighbour genotypes. In contrast, homozygous pairs of individuals for distinct isozyme loci occurred at larger spatial scales in forest stands. This indicates that biparental inbreeding due to local propagule establishment may take place to some extent in sprouters growing under favourable conditions. Our results show that sprouters follow a long-lasting genet persistence strategy which most probably is selected under unpredictable disturbance regimes, such as fire.

  6. Uptake of nitrate, ammonium and glycine by plants of Tasmanian wet eucalypt forests.

    PubMed

    Warren, C R; Adams, P R

    2007-03-01

    A central assumption of ecosystem N cycling has been that organic N must be converted to inorganic N to be available for plant uptake, but this has been questioned by recent studies. We examined uptake of nitrate, ammonium and the amino acid glycine in three species from Eucalyptus obliqua L'Her. wet forest in Tasmania, south-eastern Australia, to test the hypothesis that all three species can take up glycine, and to compare rates of glycine uptake with rates of uptake of nitrate and ammonium uptake. The alternative hypothesis that species vary in their preference for nitrate, ammonium and glycine ("niche differentiation") was also examined. Measurements were made on the canopy dominant Eucalyptus obliqua, and two rain forest tree species found in the understory or as sub-dominants of the canopy, Nothofagus cunninghamii (Hook.) Oerst. and Phyllocladus aspleniifolius (Labill.) Hook.f. Nitrogen uptake was examined in situ with attached roots placed in uptake solutions containing equimolar concentrations (100 micromol l(-1)) of (15)N-nitrate, (15)N-ammonium and 2-(13)C(2) (15)N-glycine. Species did not differ in their preference for different forms of N (species x N form interaction, P > 0.05), and thus there was no evidence of niche differentiation. In all species, rates of uptake were highest for ammonium (11 +/- 5 micromol g(DM) (-1) h(-1); mean +/- SD, n = 108), uptake of glycine occurred at less than half this rate (4.4 +/- 2.6 micromol g(DM) (-1) h(-1)), whereas uptake of nitrate occurred at one-tenth of this rate (0.9 +/- 1.2 micromol g(DM) (-1) h(-1)). The strong positive relationship between (15)N and (13)C uptake indicated that at least 72% of glycine-N was taken up intact. These findings indicate the potential for considerable uptake of organic N in the field.

  7. Succession of ground-dwelling beetle assemblages after fire in three habitat types in the Andean forest of NW Patagonia, Argentina.

    PubMed

    Sasal, Yamila; Raffaele, Estela; Farji-Brener, Alejandro G

    2010-01-01

    Wildfires are one of the major disturbances in the dynamics of forests and shrublands. However, little is known about their effects on insect communities that contribute to faunal biodiversity and play key roles in the ecosystem's dynamics. An intense and widespread fire occurred in 1999 in the Nahuel Huapi National Park in the Andean forest in northern Patagonia, Argentina. This fire affected adjacent, but different, habitat types. After the fire, beetle abundance, species richness and assemblage composition were compared among three habitats that were structurally different before the fire. These habitats were: 1) evergreen forest dominated by Nothofagus dombeyi (Mirb.) Oerst. (Fagales: Nothofagaceae), 2) a mixed forest of the evergreen conifer Austrocedrus chilensis (D. Don) Pic. Serm. and Bizzarri (Pinales: Cupressaceae) and N. dombeyi and 3) a shrubland with a diverse community of shrub species. The relationship between beetle diversity and vegetation structure was investigated over three consecutive years. Ground beetles were collected by pitfall traps, and plant species richness, vegetation cover, and height were measured. Beetle communities varied more over years between habitats during the early regeneration after fire. There was a shift in beetle assemblage composition with time after the fire in all habitat types, probably due to similar colonization rates and microclimatic conditions. Therefore, beetle succession was more influenced by recolonization and survivorship, accompanied by climatic conditions and recovery rate of plant communities over time, than it was influenced by pre-fire habitat conditions. These results suggest that in NW Patagonia, wildfire can have a substantial, short-term impact on beetle abundance and species composition. The pre-fire conditions of each habitat type determined the structure of post-fire communities of plants but not beetle assemblages. Wildfires produce simplification and homogenization of habitat types, and this

  8. Deglacial palaeoclimate at Puerto del Hambre, subantarctic Patagonia, Chile

    NASA Astrophysics Data System (ADS)

    Heusser, Calvin J.; Heusser, Linda E.; Lowell, Thomas V.; Moreira M., Andrés; Moreira M., Simón

    2000-02-01

    The primary objective of this study is to further substantiate multistep climatic forcing of late-glacial vegetation in southern South America. A secondary objective is to establish the age of deglaciation in Estrecho de Magallanes-Bahía Inútil. Pollen assemblages at 2-cm intervals in a core of the mire at Puerto del Hambre (53°3621S, 70°5553W) provide the basis for reconstructing the vegetation and a detailed account of palaeoclimate in subantarctic Patagonia. Chronology over the 262-cm length of core is regulated by 20 AMS radiocarbon dates between 14 455 and 10 089 14C yr BP. Of 13 pollen assemblage zones, the earliest representing the Oldest Dryas chronozone (14 455-13 000 14C yr BP) records impoverished steppe with decreasing frequencies and loss of southern beech (Nothofagus). Successive 100-yr-long episodes of grass/herbs and of heath (Empetrum/Ericaceae) before 14 000 14C yr BP infer deglacial successional communities under a climate of increased continentality prior to the establishment of grass-dominated steppe. The Bølling-Allerød (13 000-11 000 14C yr BP) is characterised by mesic grassland under moderating climate that with abrupt change to heath dominance after 12 000 14C yr BP was warmer and not as humid. At the time of the Younger Dryas (11 000-10 000 14C yr BP), grass steppe expanded with a return of colder, more humid climate. Later, with gradual warming, communities were invaded by southern beech. The Puerto del Hambre record parallels multistep, deglacial palaeoclimatic sequences reported elsewhere in the Southern Andes and at Taylor Dome in Antarctica. Deglaciation of Estrecho de Magallanes-Bahía Inútil is dated close to 14 455 14C yr BP, invalidating earlier dates of between 15 800 and 16 590 14C yr BP.

  9. Impacts of solar ultraviolet-B radiation on terrestrial ecosystems of Tierra del Fuego (southern Argentina). An overview of recent progress.

    PubMed

    Ballaré, C L; Rousseau, M C; Searles, P S; Zaller, J G; Giordano, C V; Robson, T M; Caldwell, M M; Sala, O E; Scopel, A L

    2001-09-01

    The southern part of Tierra del Fuego, in the southernmost tip of South America, is covered by dense Nothofagus spp. forests and Sphagnum-dominated peat bogs, which are subjected to the influence of ozone depletion and to increased levels of solar ultraviolet-B radiation (UV-B). Over the last 5 years we have studied some of the biological impacts of solar UV-B on natural ecosystems of this region. We have addressed two general problems: (i) do the fluctuations in UV-B levels under the influence of the Antarctic ozone 'hole' have any measurable biological impact, and (ii) what are the long-term effects of solar (ambient) UV-B on the Tierra del Fuego ecosystems? In this paper, we provide an overview of the progress made during the first 4 years of the project. We highlight and discuss the following results: (1) ambient UV-B has subtle but significant inhibitory effects on the growth of herbaceous and graminoid species of this region (growth reduction < or = 12%), whereas no consistent inhibitory effects could be detected in woody perennials; (2) in the species investigated in greatest detail, Gunnera magellanica, the inhibitory effect of solar UV-B is accompanied by increased levels of DNA damage in leaf tissue, and the DNA damage density in the early spring is clearly correlated with the dose of weighted UV-B measured at ground level; (3) the herbaceous species investigated thus far show little or no acclimation responses to ambient UV-B such as increased sunscreen levels and DNA repair capacity; and (4) ambient UV-B has significant effects on heterotrophic organisms, included marked inhibitory effects on insect herbivory. The results from the experiments summarized in this review clearly indicate that UV-B influences several potentially important processes and ecological interactions in the terrestrial ecosystems of Tierra del Fuego.

  10. [OVERWEIGHT AND OBESITY IN CHILDREN AND ADOLESCENTS IN FULL TIME SCHOOLS MORELOS, MÉXICO].

    PubMed

    González Rosendo, Guillermina; Villanueva Sánchez, Javier; Alcantar Rodríguez, Victor Eduardo; Quintero Gutiérrez, Adrián Guillermo

    2015-12-01

    Introducción: es común que los escolares en México presenten bajos consumos de algunos nutrimentos, y elevados consumos de energía total, grasas y sodio; también es frecuente que su actividad física sea insuficiente, lo que propicia la presencia de sobrepeso y obesidad. Objetivo: el propósito de este estudio fue identificar la prevalencia de sobrepeso y obesidad en los alumnos de escuelas de tiempo completo del estado de Morelos (México). Sujetos y métodos: estudio transversal en 30.966 alumnos de 3 a 15 años, asistentes a 186 escuelas. El estado nutricional se obtuvo a través del Índice de Masa Corporal, considerando la edad y el género; el peso se midió con básculas SECA 813 y la talla con estadímetros SECA 213; se utilizaron patrones de referencia internacionales. Resultados: de 36.482 niños y niñas censados, se midió a 30.966 (84,9%) que asistieron el día de visita. La prevalencia global de bajo peso se aproximó al 8% y la prevalencia conjunta de sobrepeso y obesidad superó el 25%. Fueron más altas las prevalencias de bajo peso y obesidad en los hombres. Conclusiones: uno de cada 12 niños tiene bajo peso; uno de cada cuatro, sobrepeso y uno de cada nueve, obesidad. La población masculina es más vulnerable a padecer consecuencias por deficiencias y excesos nutricionales. Son necesarios estudios específicos para diferenciar y atender la obesidad de tipo primario y los riesgos asociados, para definir acciones futuras.

  11. [CONSUMPTION OF OMEGA- 3 FATTY ACIDS AND DEPRESSIVE SYMPTOMS IN COLLEGE STUDENTS FROM SONORA, MEXICO].

    PubMed

    Rubi Vargas, María; González Lomelí, Daniel; Terrazas Medina, Efraín A; Peralta Peña, Sandra L; Jordán Jinez, Ma Lourdes; Ruiz Paloalto, Ma Laura; Cupul Uicab, Lea A

    2015-10-01

    Introducción: estudios recientes sugieren que los niveles bajos de acidos grasos poliinsaturados omega-3 se relacionan con una mayor prevalencia de depresion; sin embargo, los resultados no son concluyentes. Objetivo: evaluar la asociacion entre el bajo consumo de acidos grasos omega-3 y la presencia de sintomas depresivos en jovenes universitarios del noroeste de Mexico. Métodos: se realizo un estudio transversal en una muestra de 706 universitarios de 18 a 24 anos de edad de ambos sexos. La presencia de sintomatologia depresiva se estimo con la escala de Depresion del Centro de Estudios Epidemiologicos (CES-D) empleando un punto de corte ≥ 24. El consumo semanal de acidos grasos alfalinolenico (ALA) y de eicosapentaenoico (EPA) mas docosahexaenoico (DHA) en mg/g de alimento se estimo por medio de un cuestionario de frecuencia de consumo de alimentos validado para la poblacion mexicana. La asociacion del consumo de omega-3 con la presencia de sintomas depresivos se evaluo con modelos de regresion logistica. Resultados: el 67% de los participantes fueron mujeres; en general, el 16,6% presentaron sintomatologia depresiva. El consumo bajo de ALA y EPA + DHA no se asocio con mayor prevalencia de sintomatologia depresiva antes y despues de ajustar por confusores. En aquellos casos con sintomatologia depresiva, los niveles ALA derivados solo de las nueces fueron significativamente menores. Conclusiones: en esta poblacion no se observo asociacion entre el bajo consumo de acidos grasos omega-3 y la sintomatologia depresiva. La posible asociacion entre el consumo de nueces y la sintomatologia depresiva requiere de mas estudios.

  12. [TEEN MOTHER AND NEWBORN NUTRITIONAL STATUS IN A GROUP OF TEENAGERS OF THE CITY OF MEDELLIN].

    PubMed

    Restrepo-Mesa, Sandra Lucia; Zapata López, Natalia; Parra Sosa, Beatriz Elena; Escudero Vásquez, Luz Estela; Betancur Arrovaye, Laura

    2015-09-01

    Introducción: en los países en vía de desarrollo, entre ellos Colombia, el embarazo adolescente es un problema de salud pública por sus consecuencias sociales, de salud y nutrición para el binomio madre-hijo. Objetivo: evaluar las características demográficas, socioeconómicas, de seguridad alimentaria, de salud y el estado nutricional en un grupo de gestantes adolescentes y sus recién nacidos. Métodos: se realizó un estudio analítico de corte transversal con 294 embarazadas adolescentes en el tercer trimestre de gestación del programa de control prenatal de la Red Pública Hospitalaria de Medellín-Colombia, durante 2011-2012. Se buscó la asociación del índice de masa corporal materno, estado nutritivo del hierro y peso al nacer del neonato con variables explicativas. Resultados: los ingresos económicos mensuales inferiores a un salario mínimo se asociaron con bajo peso materno y con recién nacidos pequeños para la edad gestacional. El bajo peso gestacional se presentó en mayor proporción en las gestantes de 15 años o menos y con una edad ginecológica inferior a cinco años. La prevalencia de anemia fue baja en el primer trimestre y aumentó significativamente al final del embarazo; 90% presentaron reservas inadecuadas de hierro. El bajo peso al nacer se asoció con la presencia de infecciones y el bajo peso materno en el tercer trimestre de gestación. Conclusión: la gestación adolescente es un problema complejo que se asocia con efectos negativos en el estado nutricional, de salud y social de la mujer y su recién nacido.

  13. 3D geometry of growth strata in a fault-propagation fold: insights into space-time evolution of the Crevillente Fault (Abanilla-Alicante sector), Betic Cordillera, Spain

    NASA Astrophysics Data System (ADS)

    Martin-Rojas, I.; Alfaro, P.; Estévez, A.

    2015-07-01

    This work presents a 3D geometric model of growth strata cropping out in a fault-propagation fold associated with the Crevillente Fault (Abanilla-Alicante sector) from the Bajo Segura Basin (eastern Betic Cordillera, southern Spain). The analysis of this 3D model enables us to unravel the along-strike and along-section variations of the growth strata, providing constraints to assess the fold development, and hence, the fault kinematic evolution in space and time. We postulate that the observed along-strike dip variations are related to lateral variation in fault displacement. Along-section variations of the progressive unconformity opening angles indicate greater fault slip in the upper Tortonian-Messinian time span; from the Messinian on, quantitative analysis of the unconformity indicate a constant or lower tectonic activity of the Crevillente Fault (Abanilla-Alicante sector); the minor abundance of striated pebbles in the Pliocene-Quaternary units could be interpreted as a decrease in the stress magnitude and consequently in the tectonic activity of the fault. At a regional scale, comparison of the growth successions cropping out in the northern and southern limits of the Bajo Segura Basin points to a southward migration of deformation in the basin. This means that the Bajo Segura Fault became active after the Crevillente Fault (Abanilla-Alicante sector), for which activity on the latter was probably decreasing according to our data. Consequently, we propose that the seismic hazard at the northern limit of the Bajo Segura Basin should be lower than at the southern limit.

  14. Recent Advances in Maya Studies Using Remotely Sensed Data

    NASA Technical Reports Server (NTRS)

    Sever, Tom; Irwin, Daniel; Arnold, James E. (Technical Monitor)

    2001-01-01

    The Peten region of northern Guatemala is one of the last places on earth where major archeological sites remain to be discovered. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper and IKONOS satellite and airborne Star3i radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as cities, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the baJos, which are seasonally flooded swamps that cover over 40% of the land surface. The use of bajos for farming has been a source of debate within the professional community for many years. But the recent detection and verification of cultural features within the bajo system by our research team are providing conclusive evidence that the ancient Maya had adapted well to wetland environments from the earliest times and utilized them until the time of the Maya collapse. The combination of water management and bajo farming is an important resource for the future of the current inhabitants who are experiencing rapid population growth. Remote sensing imagery is also demonstrating that in the Preclassic period (600 BC- AD 250), the Maya had already achieved a high organizational level as evidenced by the construction of massive temples and an elaborate inter-connecting roadway system. Although they experienced several setbacks such as droughts and hurricanes, the Maya nevertheless managed the delicate forest ecosystem successfully for several centuries. However, around AD 800, something happened to the Maya to cause their rapid decline and eventual disappearance from the region. The evidence indicates that at this time there was increased climatic dryness, extensive deforestation, overpopulation, and widespread warfare. This raises a

  15. La crisis de vacunación contra el VPH

    Cancer.gov

    A raíz de la publicación de una declaración de consenso de los Centros Oncológicos designados por NCI sobre la vacunación contra el VPH en el país, el doctor Noel Brewer trata de los bajos indices de vacunación y de cómo el personal clínico puede ayudar.

  16. [Activities after school time and obesity in children. Influence of family and neighborhood environment].

    PubMed

    Yamamoto-Kimura, Liria T; Alvear-Galindo, Ma Guadalupe; Morán-Álvarez, Cristina; Acuña-Sánchez, Ma Eugenia; Torres-Durán, Patricia V; Juárez-Oropeza, Marco Antonio; Ferreira-Hermosillo, Aldo; Solís-Díaz, Ma Guadalupe

    2013-01-01

    Introducción: los niños de primaria en México permanecen poco tiempo en el ámbito escolar. El objetivo de este trabajo fue conocer las características somatométricas de los escolares y sus padres e investigar las actividades extraescolares que realizan y las que les gustaría realizar y la razón por la que no lo hacen. Métodos: participaron 172 niños de uno y otro sexo, de primer y segundo año de una escuela primaria oficial de una colonia marginada. Resultados: la frecuencia de bajo peso fue de 12.1 %; de sobrepeso, de 19 % y de obesidad, de 18.5 %. Las actividades sedentarias como ver la televisión y los videojuegos fueron las más altas y las deportivas las más bajas, principalmente en las niñas. La falta de tiempo de los padres, los bajos recursos económicos de la familia y la falta de espacios seguros donde los niños puedan jugar y realizar actividades físicas y deportivas fueron los factores más importantes. Conclusiones: la pobreza y la inseguridad del barrio determinan las actividades extraescolares. La alta frecuencia de bajo peso, el sobrepeso y la obesidad en los escolares se relacionaron con la falta de actividad física.

  17. The Behavioral Implications of a Multi-Individual Bonebed of a Small Theropod Dinosaur

    PubMed Central

    Ibiricu, Lucio M.; Martínez, Rubén D.; Casal, Gabriel A.; Cerda, Ignacio A.

    2013-01-01

    Background Central Patagonia, Argentina, preserves an abundant and rich fossil record. Among vertebrate fossils from the Upper Cretaceous Bajo Barreal Formation of Patagonia, five individuals of the small, non-avian theropod dinosaur Aniksosaurus darwini were recovered. Group behavior is an important aspect of dinosaur paleoecology, but it is not well-documented and is poorly understood among non-avian Theropoda. Methods/Principal Findings The taphonomic association of individuals from the Bajo Barreal Formation and aspects of their bone histology suggest gregarious behavior for Aniksosaurus, during at least a portion of the life history of this species. Histology indicates that the specimens were juvenile to sub-adult individuals. In addition, morphological differences between individuals, particularly proportions of the appendicular bones, are probably related to body-size dimorphism rather than ontogenetic stage. Conclusions/Significance Gregarious behaviour may have conferred a selective advantage on Aniksosaurus individuals, contributing to their successful exploitation of the Cretaceous paleoenvironment preserved in the Bajo Barreal Formation. The monospecific assemblage of Aniksosaurus specimens constitutes only the second body fossil association of small, coelurosaurian theropods in South America and adds valuable information about the paleoecologies of non-avian theropod dinosaurs, particularly in the early Late Cretaceous of Patagonia. PMID:23691183

  18. Applicability of the visceral adiposity index (VAI) in predicting components of metabolic syndrome in young adults.

    PubMed

    Schuster, Jéssica; Vogel, Patrícia; Eckhardt, Cristiane; Morelo, Simone Dal Bosco

    2014-10-01

    Introducción: El síndrome metabólico (SM) es uno de los principales factores de riesgo de enfermedades cardiovasculares (ECV), y la identificación de sus componentes en los adultos jóvenes puede constituir una importante herramienta de prevención. Objetivo: Analizar la aplicabilidad del Visceral Adiposity Index (VAI) para la predicción de componentes del SM en adultos jóvenes. Métodos: Estudio transversal con 444 individuos, edad 25,6 ± 6,5, 77,7% del sexo femenino. Se obtuvieron datos sobre el peso, talla, circunferencia de cintura (CC), el porcentaje de grasa corporal (%GC), glucemia, triglicéridos (TG), colesterol total (CT), colesterol HDL (HDL-c), colesterol LDL (LDL-c), y la presión arterial (PA), así como información sobre sus estilos de vida. Se calculó Índice de Masa Corporal (IMC), la proporción de cintura a la altura (PCA) y VAI. Mediciones de adiposidad se compararon con los componentes del SM, y por VAI, se determinó la capacidad predictiva de ocurrencia de los componentes de SM y el área a bajo la curva ROC. Resultados: VAI se correlaciona a la glucosa (r= 0,136), HDL-c (r=-436) y TG (r=0,825) en las mujeres y entre los hombres, se correlaciona a la glucosa (r=0,258), HDL-c (r=-0,550), TG (r=0,897), y la PAD (r= 0,290). Un aumento de VAI se asoció a un mayor riesgo de obesidad abdominal (OR=1,86), hipertrigliceridemia (OR=30,74), y bajo HDL-c (OR=3,95). Entre los indicadores de obesidad, VAI presentó una mayor área bajo la curva de aumento de triglicéridos y bajos niveles de HDL-c. Conclusión: VAI presentó una asociación a los componentes del SM en hombres, y em mujeres con un mayor riesgo de obesidad abdominal, hipertrigliceridemia y bajos niveles de HDL-c, demostrando ser un buen predictor de componentes de SM, incluso entre adultos jóvenes sanos.

  19. [In Process Citation].

    PubMed

    Santos, Carla Adriana; Fonseca, Jorge; Carolino, Elisabete; Lopes, Teresa; Sousa Guerreiro, António

    2016-01-01

    Introducción y objetivos: el cobre (Cu) es un oligoelemento muy estudiado, pero poco se sabe de su evolución en los pacientes alimentados por gastrostomía endoscópica (GEP). Pretendemos evaluar la evolución del Cu sérico desde la gastrostomía hasta 12 semanas después de la intervención en estos pacientes alimentados con preparaciones domésticas.  Métodos: realizamos un estudio observacional prospectivo para evaluar el Cu sérico, la albúmina, la transferrina y el índice de masa corporal (IMC) en el momento de la GEP, tras 4 semanas y 12 semanas después de la intervención. Los datos incluyen edad, género, NRS 2002 y enfermedad subyacente: cánceres de cabeza y cuello (CCC) y disfagia neurológica (DN). Después de la intervención, estos pacientes fueron alimentados conpreparaciones domésticas. Resultados: 146 enfermos (89 hombres), entre 21-95 años: CCC-56, DN-90. Valores de Cu entre 42-160 μg/dl (normal: 70-140 μg/dl); normales 89% (n = 130); bajos 11% (n = 16), albúmina baja: 53% (n = 77), transferrina baja: 65% (n = 94), IMC bajo: 53% (n = 78). Después de 4 semanas: valores normales de Cu en 93% y bajos en 7%, albúmina baja en 34%, transferrina baja en 52%. Tras 12 semanas: valores normales de Cu en 95% y bajos en 5%, albúmina baja en 25%, transferrina baja en 32%. No encontramos diferencias significativas en el Cusérico cuando se compara edad, género, enfermedad subyacente, IMC, albúmina y transferrina. Conclusiones: la mayoría de los enfermos presentan Cu sérico normal en el momento de la gastrostomía. Para los enfermos con Cu sérico bajo antes del procedimiento, la alimentación con preparaciones domésticas parece suficiente para su normalización progresiva. PMID:27238774

  20. [In Process Citation].

    PubMed

    Santos, Carla Adriana; Fonseca, Jorge; Carolino, Elisabete; Lopes, Teresa; Sousa Guerreiro, António

    2016-03-25

    Introducción y objetivos: el cobre (Cu) es un oligoelemento muy estudiado, pero poco se sabe de su evolución en los pacientes alimentados por gastrostomía endoscópica (GEP). Pretendemos evaluar la evolución del Cu sérico desde la gastrostomía hasta 12 semanas después de la intervención en estos pacientes alimentados con preparaciones domésticas.  Métodos: realizamos un estudio observacional prospectivo para evaluar el Cu sérico, la albúmina, la transferrina y el índice de masa corporal (IMC) en el momento de la GEP, tras 4 semanas y 12 semanas después de la intervención. Los datos incluyen edad, género, NRS 2002 y enfermedad subyacente: cánceres de cabeza y cuello (CCC) y disfagia neurológica (DN). Después de la intervención, estos pacientes fueron alimentados conpreparaciones domésticas. Resultados: 146 enfermos (89 hombres), entre 21-95 años: CCC-56, DN-90. Valores de Cu entre 42-160 μg/dl (normal: 70-140 μg/dl); normales 89% (n = 130); bajos 11% (n = 16), albúmina baja: 53% (n = 77), transferrina baja: 65% (n = 94), IMC bajo: 53% (n = 78). Después de 4 semanas: valores normales de Cu en 93% y bajos en 7%, albúmina baja en 34%, transferrina baja en 52%. Tras 12 semanas: valores normales de Cu en 95% y bajos en 5%, albúmina baja en 25%, transferrina baja en 32%. No encontramos diferencias significativas en el Cusérico cuando se compara edad, género, enfermedad subyacente, IMC, albúmina y transferrina. Conclusiones: la mayoría de los enfermos presentan Cu sérico normal en el momento de la gastrostomía. Para los enfermos con Cu sérico bajo antes del procedimiento, la alimentación con preparaciones domésticas parece suficiente para su normalización progresiva.

  1. Systematics, biogeography, and evolution of Hemidactylus geckos (Reptilia: Gekkonidae) elucidated using mitochondrial DNA sequences.

    PubMed

    Carranza, S; Arnold, E N

    2006-02-01

    With more than 80 species inhabiting all warm continental land masses and hundreds of intervening continental and oceanic islands, Hemidactylus geckos are one of the most species-rich and widely distributed of all reptile genera. They consequently represent an excellent model for biogeographic, ecological, and evolutionary studies. A molecular phylogeny for Hemidactylus is presented here, based on 702 bp of mtDNA (303 bp cytochrome b and 399 bp 12S rRNA) from 166 individuals of 30 species of Hemidactylus plus Briba brasiliana, Cosymbotus platyurus, and several outgroups. The phylogeny indicates that Hemidactylus may have initially undergone rapid radiation, and long-distance dispersal is more extensive than in any other reptilian genus. In the last 15 My, African lineages have naturally crossed the Atlantic Ocean at least twice. They also colonized the Gulf of Guinea, Cape Verde and Socotra islands, again sometimes on more than one occasion. Many extensive range extensions have occurred much more recently, sometimes with devastating consequences for other geckos. These colonizations are likely to be largely anthropogenic, involving the 'weedy' commensal species, H. brookii s. lat, H. mabouia, H. turcicus, H. garnotii, and H. frenatus. These species collectively have colonized the Mediterranean region, tropical Africa, much of the Americas and hundreds of islands in the Pacific, Indian, and Atlantic oceans. Five well-supported clades are discernable in Hemidactylus, with the African H. fasciatus unallocated. 1. Tropical Asian clade: (Cosymbotus platyurus (H. bowringii, H. karenorum, H. garnotii)) (H. flaviviridis (Asian H. brookii, H. frenatus)). 2. African H. angulatus and Caribbean H. haitianus. 3. Arid clade, of NE Africa, SW Asia, etc.: (H. modestus (H. citernii, H. foudai)) (H. pumilio (H. granti, H. dracaenacolus) (H. persicus, H. macropholis, H. robustus, H. turcicus (H. oxyrhinus (H. homoeolepis, H. forbesii))). 4. H. mabouia clade (H. yerburii, H. mabouia

  2. The Puf family of RNA-binding proteins in plants: phylogeny, structural modeling, activity and subcellular localization

    PubMed Central

    2010-01-01

    Background Puf proteins have important roles in controlling gene expression at the post-transcriptional level by promoting RNA decay and repressing translation. The Pumilio homology domain (PUM-HD) is a conserved region within Puf proteins that binds to RNA with sequence specificity. Although Puf proteins have been well characterized in animal and fungal systems, little is known about the structural and functional characteristics of Puf-like proteins in plants. Results The Arabidopsis and rice genomes code for 26 and 19 Puf-like proteins, respectively, each possessing eight or fewer Puf repeats in their PUM-HD. Key amino acids in the PUM-HD of several of these proteins are conserved with those of animal and fungal homologs, whereas other plant Puf proteins demonstrate extensive variability in these amino acids. Three-dimensional modeling revealed that the predicted structure of this domain in plant Puf proteins provides a suitable surface for binding RNA. Electrophoretic gel mobility shift experiments showed that the Arabidopsis AtPum2 PUM-HD binds with high affinity to BoxB of the Drosophila Nanos Response Element I (NRE1) RNA, whereas a point mutation in the core of the NRE1 resulted in a significant reduction in binding affinity. Transient expression of several of the Arabidopsis Puf proteins as fluorescent protein fusions revealed a dynamic, punctate cytoplasmic pattern of localization for most of these proteins. The presence of predicted nuclear export signals and accumulation of AtPuf proteins in the nucleus after treatment of cells with leptomycin B demonstrated that shuttling of these proteins between the cytosol and nucleus is common among these proteins. In addition to the cytoplasmically enriched AtPum proteins, two AtPum proteins showed nuclear targeting with enrichment in the nucleolus. Conclusions The Puf family of RNA-binding proteins in plants consists of a greater number of members than any other model species studied to date. This, along with the

  3. Fish-borne zoonotic trematodes in cultured and wild-caught freshwater fish from the Red River Delta, Vietnam.

    PubMed

    Phan, Van Thi; Ersbøll, Annette Kjaer; Bui, Te Quang; Nguyen, Hang Thi; Murrell, Darwin; Dalsgaard, Anders

    2010-11-01

    Nam Dinh province in Red River Delta, Vietnam, is an endemic area for the human liver fluke Clonorchis sinensis, but little is known about its occurrence in the fish intermediate host in this region. A cross-sectional study was carried out to identify fish-borne zoonotic trematodes (FZT) species diversity and to estimate the prevalence and infection densities of FZT in three major types of fish: cultured species and self-recruiting species from family ponds and wild-caught species from irrigation canals in Nam Dinh province. A total of 714 wild-caught fish from canals and 829 fish from family ponds were examined for FZT infection. Only a single fish from a pond was infected with Cl. sinensis. The intestinal fluke Haplorchis pumilio was very common and found in more than 50% of fish irrespective of origin. Four other intestinal FZT species were found at low prevalence (<4.0%) except Procerovum varium, which was found in 14.4% of wild-caught fish. There was no significant difference (p > 0.05) in FZT prevalence in cultured fish (64.3%) compared with wild-caught fish (68.9%), nor between cultured fish species (65.1%) and self-recruiting species obtained from ponds (58.1%). The prevalence of FZT in silver carp (Hypophthalmichthys molitrix) (82.7%), grass carp (Ctenopharyngodon idellus) (76.9%), and mrigal (Cirrhinus mrigala) (63.8%) was significantly higher than that in rohu (Labeo rohita) (49.1%) (p < 0.001). The density of FZT metacercariae in fish from canals (0.56 metacercariae/g) was significantly higher (p < 0.001) than that in fish from ponds (0.03 metacercariae/g). The frequent occurrence of intestinal flukes in all fish types indicates that wild-caught and cultured fish are equally at risk of infection with FZT, particularly in species commonly used in Nam Dinh to prepare raw fish dishes. These results underscore the need for greater awareness of the risk from raw fish dishes among public health agencies and consumers. PMID:20370427

  4. Recent Deglaciation of Darwin Mountains (Tierra de Fuego) after Little Ice Age: monitoring by photogrammetry, lichenometry, dendrochronology and field studies.

    NASA Astrophysics Data System (ADS)

    García-Sancho, L.; Palacios, D.; Zamorano, J. J.; Green, A.; Vivas, M.; Pintado, A.

    2012-04-01

    Glaciers from the Darwin mountain range have been retreating since the Little Ice Age (LIA). However, the amount of retreat varies and is minimal for some glacial snouts and substantial for others. Possible explanations for this different behaviour include climatic and glacial dynamic causes. The aim of this work was to analyse the impact of climate change on these glaciers. The research site was the terminus of glacier Pia, which descends to the south of Mount Darwin (2488 m asl, 54°45'S, 69°29'W) and reaches the coastline at the Beagle Channel. The terminus is situated some hundreds of meters above the LIA moraine but, whereas one sector retreated rapidly and then stabilized, another sector has had several advances and retreats leaving a number of moraine arches. To better understand the origin of this dynamic behaviour, we undertook a study of the evolution of the terminus of glacier Pia over the last 60 years. We used aerial photographs and satellite images to determine the exact location of the glacial terminus in certain years (1943, 1963, 1987, 1990, 2001 and 2006). These results were completed in 2008 and 2009 through field work. We also carried out lichenometric studies of the two most abundant lichen species that rapidly colonize the moraine boulders abandoned by the glacier: Placopsis perrugosa and Rhizocarpon geographicum. By comparing results from field work carried out in 2008 and 2009, we were able to determine the growth rate of these two species (García-Sancho et al. 2011). In addition, we also carried out a dendrochronological study of Nothofagus antarctica and N. betuloides. The use of the four techniques involved in this study (photogrammetry, lichenometry, dendrochronology and multiyear field work) allowed us to establish the ecesis period of each species as well as their growth curves, from which we can deduce the movements of the glacial terminus from the end of the LIA to the present. From this study we can infer that the different

  5. A review of Tertiary climate changes in southern South America and the Antarctic Peninsula. Part 2: continental conditions

    NASA Astrophysics Data System (ADS)

    Le Roux, J. P.

    2012-03-01

    uninterruptedly into the Pleistocene. The Antarctic Peninsula saw its first mountain glaciation between 45 and 41 Ma, with major ice sheet expansion commencing at about 34 Ma. Isolated stands of Nothofagus forests were still present in low-lying areas, suggesting that the glaciers were initially wet-based, but dry-based glaciers were established at around 8 Ma. Although temperatures rose briefly during the Messinian-Pliocene transition, causing sub-Antarctic flora to retreat to higher elevations of the Transantarctic Mountains, the present cold polar conditions were finally established by about 3 Ma.

  6. A Geochemical and Sedimentary Record of High Southern Latitude Holocene Climate Evolution from Lago Fagnano, Tierra del Fuego

    SciTech Connect

    Moy, C M; Dunbar, R B; Guilderson, T P; Waldmann, N; Mucciarone, D A; Recasens, C; Austin, J A; Anselmetti, F S

    2010-11-19

    Situated at the southern margin of the hemispheric westerly wind belt and immediately north of the Antarctic Polar Frontal zone, Tierra del Fuego is well-positioned to monitor coupled changes in the ocean-atmosphere system of the high southern latitudes. Here we describe a Holocene paleoclimate record from sediment cores obtained from Lago Fagnano, a large lake in southern Tierra del Fuego at 55{sup o}S, to investigate past changes in climate related to these two important features of the global climate system. We use an AMS radiocarbon chronology for the last 8,000 years based on pollen concentrates, thereby avoiding contamination from bedrock-derived lignite. Our chronology is consistent with a tephrochronologic age date for deposits from the middle Holocene Volcan Hudson eruption. Combining bulk organic isotopic ({delta}{sup 13}C and {delta}{sup 15}N) and elemental (C and N) parameters with physical sediment properties allow us to better understand sediment provenance and transport mechanisms and to interpret Holocene climate and tectonic change during the last 8,000 years. Co-variability and long-term trends in C/N ratio, carbon accumulation rate, and magnetic susceptibility reflect an overall Holocene increase in the delivery of terrestrial organic and lithogenic material to the deep eastern basin. We attribute this variability to westerly wind-derived precipitation. Increased wind strength and precipitation in the late Holocene drives the Nothofagus forest eastward and enhances run-off and terrigenous inputs to the lake. Superimposed on the long-term trend are a series of abrupt 9 negative departures in C/N ratio, which constrain the presence of seismically-driven mass flow events in the record. We identify an increase in bulk {delta}{sup 13}C between 7,000 and 5,000 cal yr BP that we attribute to enhanced aquatic productivity driven by warmer summer temperatures. The Lago Fagnano {delta}{sup 13}C record shows similarities with Holocene records of sea surface

  7. A multi-proxy lacustrine record of Holocene climate change in SW Patagonia, Chile

    NASA Astrophysics Data System (ADS)

    LeRoy, S. L.; Mucciarone, D. A.; Dunbar, R. B.

    2014-12-01

    One of the largest uncertainties in the Holocene ocean-atmosphere carbon cycle is the role of the Southern Ocean (SO) and subpolar seas in controlling atmospheric CO2 levels. The strength and position of the westerly winds is thought to control rates of CO2 exchange as well as depth of ventilation. Secondarily, through their control on the large scale geostrophic circulation, the westerlies influence the position of major ocean frontal boundaries as well as stratification in the Southern Ocean - additional controls on SO carbon uptake. However, little is known about westerly wind variability over the Holocene. Southern Patagonia is an ideal locality for addressing this uncertainty, as it is the only major landmass that extends into the southern westerly wind field. In particular, lake and fjord environments hold potential for reconstructing precipitation, which is closely correlated with westerly wind strength in this region. Here we present a multi-proxy lacustrine sediment core record from Lago Sarmiento (51.06˚S, 72.91˚W), a large, closed-basin lake in southwest Chilean Patagonia. We observe highly variable C:N ratios between ~12,500 and ~6,000 14C yr BP, indicating recurrent transitions from grassland to forest. We measured a steady increase in the C:N ratio from ~6,000 14C yr BP to present, indicating a sustained shift from grassland to the modern Nothofagus forest and more humid conditions. We observe a general decreasing trend in bulk carbonate δ18O since ~4,000 14C yr BP, which we interpret as a progressive increase in westerly wind intensity and associated tendency towards positive water balance. Weight percent bulk carbonate varies greatly, with a strong decreasing trend in the early Holocene, followed by an increasing trend during the mid-Holocene, and a dip followed by a short rise in the late Holocene. Comparison with other records from southern Patagonia and Antarctica is improving our understanding of the forcing mechanisms driving changes in the

  8. Lichen Persistence and Recovery in Response to Varied Volcanic Disturbances

    NASA Astrophysics Data System (ADS)

    Nelson, P.; Wheeler, T. B.

    2015-12-01

    Volcanic eruptions produce many ecological disturbances that structure vegetation. While lichens are sensitive to disturbances, little is known about their responses to volcanic disturbances, except for colonization of lava. We examined lichen community responses through time to different disturbances produced by the May 1, 2008 eruption of Volcan Chaiten in south-central Chile. Pre-eruption vegetation near the volcano was old-growth Valdivian temperate rainforest dominated by closed-canopy Nothofagus sp... In 2012, we installed thirteen 1-acre plots across volcanic disturbance zones on which a time-constrained search was done for all macrolichen species, each of which was assigned an approximate log10 categorical abundance. We also installed a 0.2 m2 quadrat on two representative trees per plot for repeat photography of lichen cover. We remeasured at least one plot per disturbance zone in 2014 and re-photographed tree quadrats in 2013 and 2014. We then analyzed species composition and abundance differences among disturbance zones. In 2012, the blast (pyroclastic density flow), scorch (standing scorched forest at the edge of the blast) and deep tephra (>10 cm) zones had the lowest lichen species richness (5-13 species), followed by reference (unimpacted) and shallow (<10 cm) tephra (17-20 species). Gravel rain (preexisting rock ejected by eruption initiation), gravel rain + pumice and flooded forests (fluvially reworked volcanic material entrained by heavy rains) were species-rich (25-42 species). In 2014, the blast and deep tephra had regained 2-3 times the number of lichen species since 2012 while the light tephra and reference were essentially unchanged. Gravel rain, gravel rain + pumice and flooded forest plots all had about the same number of species in 2014 as 2012. Lichen colonization and growth in tree quadrats varied widely, from very little colonization in the blast to prolific colonization in the gravel rain + pumice zone. Lichen's varied responses to

  9. Multiproxy approach revealing climate and cultural changes during the last 26kyrs in south-central Chile

    NASA Astrophysics Data System (ADS)

    Abarzua, Ana M.; Jarpa, Leonora; Martel, Alejandra; Vega, Rodrigo; Pino, Mario

    2010-05-01

    Multiproxy approach from Purén Lumaco Valley (38°S) describes the paleonvironmental history during the Last Maximum Glacial (LGM) in south-central Chile. Three sediment cores and severals AMS 14C dates were used to perform a complete pollen, diatoms, chironomids, and sedimentological records demonstrating the existence of a large and non profundal paleolake, between 25 and 20kyr BP. Some of these evidence are laminated silty-clay sediments (lacustrine rhythmites), associated with the presence of siderite mineral (FeCO3), besides biological proxies like Fragilaria construens and Stauroforma inermes (planctonic diatoms), and Dicrotendipes sp. and Tanytarsini tribe (littoral chironomids). The pollen ensemble reveals the first glacial refuge of Araucaria araucana forests in the low lands during the LGM. The lake was drained abruptly into a swamp/bog at 12kyr BP and colonized by Myrtaceae wet forest. This evidence suggest the dry/warm climate period of early Holocene in south-central Chile. Later, the sediments indicate variable lacustrine levels, and increase of charcoal particles, associated to current climatic conditions. The pollen spectrum dominated by Myrtaceae and Nothofagus contrasts with a strongly disturb current landscape. Actually, Purén-Lumaco valley constitutes a complex peat-bog system dominated by exotic grasses and forest species (Tritricum aestivum, Pinus radiata and Eucalyptus spp.). Some archaeological antecedents in the area document the human development at ca. 7yrs BP. The greatest archaeological characteristic present in the valley is the kuel, a Mapuche earth accumulation. The presence and extension of almost 300 kuel in the valley reflect the social/economic development, and partly explains why the region was the major resistance area for Spanish colonizer during XVI-XVII centuries. Also the archaeological findings reveal the presence of maize pollen (Zea mays) within their food consumption. The influence of climate and human impact in

  10. Major Mid-Miocene Climate Change In The Transantarctic Mountains

    NASA Astrophysics Data System (ADS)

    Ashworth, A. C.; Lewis, A. R.; Marchant, D. R.

    2007-12-01

    Independent lines of evidence from paleoecology, glacial geology and marine isotopes indicate major climate change in the Dry Valley sector of the Transantarctic Mountains (TAM) at c.14 Ma. A fossil assemblage of pollen and spores, freshwater diatoms, ostracods, mosses, and insect remains has been recovered from lacustrine sediments preserved in a small morainic lake basin in the western Olympus Range. The diatom assemblage indicates that the lake existed for >103yr and was ice-free during summers. Based on the moss and insect fossils the minimum mean summer temperature (MST- Dec-Feb) was 2°C but could have been as high as 5°C. Today at the site the MST is c. -15°C. The lake-marginal vegetation was a sparse tundra dominated by mosses and liverworts. Based on pollen, Nothofagus (southern beech) was part of the lowland regional vegetation and individual dwarfed shrubs may have grown on the slopes surrounding the lake basin. The age of the deposits is well-constrained by an 40Ar/39Ar age of 14.11 ± 0.11 Ma from an in situ volcanic ash within related lacustrine sediments. Based on an independent study of the glacial stratigraphy of the western Wright and McKelvey valleys, diamictites of a wet-based glacial regime had been replaced by those of cold-based regime by 13.85 ± 0.03 Ma. The drop in temperatures and the cessation of meltwater at c. 14 Ma would have caused the regional extinction of all plant and insect life with the exception of the hardiest of soil-dwelling organisms. Paleobotanical evidence indicates that Antarctica had likely been vegetated throughout the Cenozoic, with forests replaced by tundra during the early Oligocene. The mid-Miocene extinction marks the end of tundra in the interior of Antarctica and its replacement by the polar desert biota which exists today. Changes in δ18O and Mg/Ca ratios from different sectors of the Southern Ocean indicate sea surface temperature cooling and ice sheet growth between 13.8 - 14.2 Ma. The close correlation

  11. The Neogene Environment of the Beardmore Glacier, Transantarctic Mountains

    NASA Astrophysics Data System (ADS)

    Ashworth, A. C.; Cantrill, D. J.; Francis, J. E.; Roof, S. R.

    2004-12-01

    , the absence of solar heating for about 5.5 months, even though there would have been additional heat from open water in the fjord, would have resulted in a low mean annual temperature. Mean summer temperatures, based on the minimal thermal requirements for Nothofagus, listroderine weevils, and freshwater molluscs, are estimated to have been between 4 and 5°C for at least two summer months. The research is supported by NSF grant OPP-0230696

  12. A geochemical and sedimentary record of high southern latitude Holocene climate evolution from Lago Fagnano, Tierra del Fuego

    NASA Astrophysics Data System (ADS)

    Moy, Christopher M.; Dunbar, Robert B.; Guilderson, Thomas P.; Waldmann, Nicolas; Mucciarone, David A.; Recasens, Cristina; Ariztegui, Daniel; Austin, James A.; Anselmetti, Flavio S.

    2011-02-01

    Situated at the southern margin of the hemispheric westerly wind belt and immediately north of the Antarctic Polar Frontal zone, Tierra del Fuego is well-positioned to monitor coupled changes in the ocean-atmosphere system of the high southern latitudes. Here we describe a Holocene paleoclimate record from sediment cores obtained from Lago Fagnano, a large lake in southern Tierra del Fuego at 55°S, to investigate past changes in climate related to these two important features of the global climate system. We use an AMS radiocarbon chronology for the last 8000 yr based on pollen concentrates, thereby avoiding contamination from bedrock-derived lignite. Our chronology is consistent with a tephrochronologic age date for deposits from the middle Holocene Volcán Hudson eruption. Combining bulk organic isotopic (δ13C and δ15N) and elemental (C and N) parameters with physical sediment properties allows us to better understand sediment provenance and transport mechanisms and to interpret Holocene climate and tectonic change during the last 8000 yr. Co-variability and long-term trends in C/N ratio, carbon accumulation rate, and magnetic susceptibility reflect an overall Holocene increase in the delivery of terrestrial organic and lithogenic material to the deep eastern basin. We attribute this variability to westerly wind-derived precipitation. Increased wind strength and precipitation in the late Holocene drives the Nothofagus forest eastward and enhances run-off and terrigenous inputs to the lake. Superimposed on the long-term trend are a series of abrupt 9 negative departures in C/N ratio, which constrain the presence of seismically-driven mass flow events in the record. We identify an increase in bulk δ13C between 7000 and 5000 cal yr BP that we attribute to enhanced aquatic productivity driven by warmer summer temperatures. The Lago Fagnano δ13C record shows similarities with Holocene records of sea surface temperature from the mid-latitude Chilean continental

  13. Phylogenetic diversity of true morels (Morchella), the main edible non-timber product from native Patagonian forests of Argentina.

    PubMed

    Pildain, María B; Visnovsky, Sandra B; Barroetaveña, Carolina

    2014-01-01

    Morchella species are edible fungi in high demand and therefore command high prices in world markets. Phenotypic-based identification at the species-level remains inadequate because of their complex life cycles, minor differences and plasticity of morphological characteristics between species, and the lack of agreement between scientific and common names. In Patagonia-Argentina, morels are associated with native forests of Austrocedrus chilensis (Cordilleran or Chilean cypress) and Nothofagus antarctica (ñire) and several exotic conifers that were introduced from western North America. Little is known about their taxonomy and phylogenetic relationships with other species in the genus. This work focused on the identification of collections of Morchella from Patagonia and their phylogenetic relationships with other species from the Northern Hemisphere. The comparison was made by analysis of DNA sequences obtained from four loci: the nuclear ribosomal internal transcribed spacer region (ITS) and the partial RNA polymerase I gene (RPB1) for the complete collection; and ITS, RPB1, RNA polymerase II gene (RPB2), and translation elongation factor (EF1-α) for the species-rich Elata Subclade. Analyses of individual and combined data sets revealed that Patagonian morels belong to the Elata Clade and comprised three strongly supported species-level lineages from both Patagonian native forest, and exotic trees introduced from western North America. One lineage was identified as Morchella frustrata phylogenetic species Mel-2, which is known from the USA and Canada. The second lineage, which appeared to be 'fire-adapted', was identified as Morchella septimelata phylogenetic species (Mel-7), which is also known from the USA. This species was collected from burned native forests mainly composed of A. chilensis and N. antarctica but also Pseudotsuga menziesii (Mirb.) Blanco, which is native to western North America. The phylogenetic analyses suggested that the third species from

  14. Oligocene to Miocene terrestrial climate change and the demise of forests on Wilkes Land, East Antarctica

    NASA Astrophysics Data System (ADS)

    Salzmann, Ulrich; Strother, Stephanie; Sangiorgi, Francesca; Bijl, Peter; Pross, Joerg; Woodward, John; Escutia, Carlota; Brinkhuis, Henk

    2016-04-01

    The question whether Cenozoic climate was warm enough to support a substantial vegetation cover on the Antarctic continent is of great significance to the ongoing controversial debate on the dynamic behaviour of Antarctic land ice during the transition from a greenhouse to an icehouse world. Here we present palynological results from an Oligocene to Miocene sediment record provided by the Integrated Ocean Drilling Program Expedition 318 to the Wilkes Land margin (East Antarctica). The Oligocene assemblages (33.9-23 Ma) are dominated by pollen and spores from temperate forest and sub-Antarctic shrub vegetation inhabiting different altitudinal zones. These include a lowland cold temperate forest with Dacrydium and Lagarostrobos (both common in southern forests of New Zealand and Tasmania today) and a high altitude tundra shrubland comprising Microcachrys, Nothofagus (southern beech) and Podocarpaceae conifers. A decline in pollen percentages of Dacrydium and Lagarostrobos and absence of Proteaceae indicate climate cooling during the late Oligocene (~25-23 Ma). However, the continuous presence of Lagarostrobos suggests that the full transition to a tundra environment had not yet occurred and climate on Wilkes Land during the late Oligocene was still warm enough to support forest vegetation in sheltered areas. Temperature reconstructions derived from the fossil pollen assemblages using the Coexistence Approach suggest mean annual temperatures (MATs) between 6.7-13.7°C during the early Oligocene and a drop of minimum MATs to 5.8°C in the late Oligocene. Pollen of "unambiguous" forest indicators, such as Lagarostrobos, are absent in the Miocene sediment record (16.2 -12.5 Ma) but temperatures were still high enough (minimum MATs > 5°C) to sustain a woody sub-Antarctic vegetation under partially ice-free conditions. Wilkes Land provides a unique record of Antarctic vegetation change from a subtropical, highly diverse Eocene rainforest to an Oligocene cold temperate

  15. Southern high-latitude terrestrial climate change during the Palaeocene-Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau)

    NASA Astrophysics Data System (ADS)

    Contreras, L.; Pross, J.; Bijl, P. K.; O'Hara, R. B.; Raine, J. I.; Sluijs, A.; Brinkhuis, H.

    2014-07-01

    Reconstructing the early Palaeogene climate dynamics of terrestrial settings in the high southern latitudes is important to assess the role of high-latitude physical and biogeochemical processes in the global climate system. However, whereas a number of high-quality Palaeogene climate records has become available for the marine realm of the high southern latitudes over the recent past, the long-term evolution of coeval terrestrial climates and ecosystems is yet poorly known. We here explore the climate and vegetation dynamics on Tasmania from the middle Palaeocene to the early Eocene (60.7-54.2 Ma) based on a sporomorph record from Ocean Drilling Program (ODP) Site 1172 on the East Tasman Plateau. Our results show that three distinctly different vegetation types thrived on Tasmania under a high-precipitation regime during the middle Palaeocene to early Eocene, with each type representing different temperature conditions: (i) warm-temperate forests dominated by gymnosperms that were dominant during the middle and late Palaeocene (excluding the middle/late Palaeocene transition); (ii) cool-temperate forests dominated by southern beech (Nothofagus) and araucarians that transiently prevailed across the middle/late Palaeocene transition interval (~ 59.5 to ~ 59.0 Ma); and (iii) paratropical forests rich in ferns that were established during and in the wake of the Palaeocene-Eocene Thermal Maximum (PETM). The transient establishment of cool-temperate forests lacking any frost-sensitive elements (i.e. palms and cycads) across the middle/late Palaeocene transition interval indicates markedly cooler conditions, with the occurrence of frosts in winter, on Tasmania during that time. The integration of our sporomorph data with previously published TEX86-based sea-surface temperatures from ODP Site 1172 documents that the vegetation dynamics on Tasmania were closely linked with the temperature evolution in the Tasman sector of the Southwest Pacific region. Moreover, the

  16. Southern high-latitude terrestrial climate change during the Paleocene-Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau)

    NASA Astrophysics Data System (ADS)

    Contreras, L.; Pross, J.; Bijl, P. K.; O'Hara, R. B.; Raine, J. I.; Sluijs, A.; Brinkhuis, H.

    2014-01-01

    Reconstructing the early Paleogene climate dynamics of terrestrial settings in the high southern latitudes is important to assess the role of high-latitude physical and biogeochemical processes in the global climate system. However, whereas a number of high-quality Paleogene climate records has become available for the marine realm of the high southern latitudes over the recent past, the long-term evolution of coeval terrestrial climates and ecosystems is yet poorly known. We here explore the climate and vegetation dynamics on Tasmania from the middle Paleocene to the early Eocene (60.7-54.2 Ma) based on a sporomorph record from Ocean Drilling Program (ODP) Site 1172 on the East Tasman Plateau. Our results show that three distinctly different vegetation types thrived on Tasmania under a high-precipitation regime during the middle Paleocene to early Eocene, with each type representing different temperature conditions: (i) warm-temperate forests dominated by gymnosperms that were dominant during the middle and late Paleocene; (ii) cool-temperate forests dominated by southern beech (Nothofagus) and araucarians across the middle/late Paleocene transition interval (~59.5 to ~59.0 Ma); and (iii) paratropical forests rich in ferns that were established during and in the wake of the Paleocene-Eocene Thermal Maximum (PETM). The transient establishment of cool-temperate forests lacking any frost-sensitive elements (i.e., palms and cycads) across the middle/late Paleocene transition interval indicates markedly cooler conditions, with the occurrence of frosts in winter, on Tasmania during that time. The integration of our sporomorph data with previously published TEX86-based sea-surface temperatures from ODP Site 1172 documents that the vegetation dynamics on Tasmania were closely linked with the temperature evolution in the Tasman sector of the Southwest Pacific region. Moreover, the comparison of our season-specific climate estimates for the sporomorph assemblages from ODP

  17. Effects of Seasonal Upwelling on Inorganic and Organic Matter Dynamics in the Water Column of Eastern Pacific Coral Reefs.

    PubMed

    Stuhldreier, Ines; Sánchez-Noguera, Celeste; Rixen, Tim; Cortés, Jorge; Morales, Alvaro; Wild, Christian

    2015-01-01

    The Gulf of Papagayo at the northern Pacific coast of Costa Rica experiences pronounced seasonal changes in water parameters caused by wind-driven coastal upwelling. While remote sensing and open water sampling already described the physical nature of this upwelling, the spatial and temporal effects on key parameters and processes in the water column have not been investigated yet, although being highly relevant for coral reef functioning. The present study investigated a range of water parameters on two coral reefs with different exposure to upwelling (Matapalo and Bajo Rojo) in a weekly to monthly resolution over one year (May 2013 to April 2014). Based on air temperature, wind speed and water temperature, three time clusters were defined: a) May to November 2013 without upwelling, b) December 2013 to April 2014 with moderate upwelling, punctuated by c) extreme upwelling events in February, March and April 2014. During upwelling peaks, water temperatures decreased by 7°C (Matapalo) and 9°C (Bajo Rojo) to minima of 20.1 and 15.3°C respectively, while phosphate, ammonia and nitrate concentrations increased 3 to 15-fold to maxima of 1.3 μmol PO43- L-1, 3.0 μmol NH4+ L-1 and 9.7 μmol NO3- L-1. This increased availability of nutrients triggered several successive phytoplankton blooms as indicated by 3- (Matapalo) and 6-fold (Bajo Rojo) increases in chlorophyll a concentrations. Particulate organic carbon and nitrogen (POC and PON) increased by 40 and 70% respectively from February to April 2014. Dissolved organic carbon (DOC) increased by 70% in December and stayed elevated for at least 4 months, indicating high organic matter release by primary producers. Such strong cascading effects of upwelling on organic matter dynamics on coral reefs have not been reported previously, although likely impacting many reefs in comparable upwelling systems. PMID:26560464

  18. Explicación de las disparidades raciales en la salud neonatal en Brasil*

    PubMed Central

    Nyarko, Kwame A.; López-Camelo, Jorge; Castilla, Eduardo E.; Wehby, George L.

    2015-01-01

    Objetivos. Buscamos cuantificar la manera en que los efectos socioeconómicos, demográficos, geográficos y de atención de salud explican las disparidades raciales en las tasas de bajo peso al nacer y prematuridad en Brasil. Métodos. Utilizamos una muestra de 8 949 niños nacidos entre 1995 y el 2009 en 15 ciudades y 7 provincias de Brasil. Nos centramos en las disparidades en la prevalencia de bajo peso al nacer (< 2 500 g) y prematuridad (< 37 semanas de gestación) en recién nacidos de ascendencia solo africana o mezclada con otras ascendencias y de ascendencia solo europea. Usamos un modelo de descomposición para cuantificar la contribución de los factores conceptualmente pertinentes a esas disparidades. Resultados. El modelo permitió explicar entre 45% y 94% de las disparidades en cuanto al bajo peso al nacer y entre 64% y 94% de las disparidades en cuanto a la prematuridad entre los grupos de ascendencia africana y de ascendencia europea. Las diferencias en el uso de atención prenatal y en la ubicación geográfica fueron los factores más importantes, seguidos por las diferencias socioeconómicas. El modelo permitió explicar la mayoría de las disparidades en los recién nacidos de ascendencia africana mezclada y parte de las disparidades en los de ascendencia solo africana. Conclusiones. En las políticas públicas para mejorar la salud infantil se deben abordar las diferencias en cuanto a la atención prenatal y la ubicación geográfica a fin de reducir las disparidades en materia de salud entre los recién nacidos de ascendencia africana y los de ascendencia europea en Brasil.

  19. [Nutritional status of two generations of brothers and sisters <5 years of age beneficiaries from opportunities living in marginalized rural communities in Chiapas, Mexico].

    PubMed

    García-Parra, Esmeralda; Ochoa-Díaz-López, Héctor; García-Miranda, Rosario; Moreno-Altamirano, Laura; Morales, Helda; Estrada-Lugo, Erin Ingrid Jane; Solís-Hernández, Roberto

    2015-06-01

    En México, en las últimas décadas se han desarrollado varios programas para erradicar el problema de la desnutrición en infantes < de 5 años, principalmente de aquellos que viven en áreas indígenas y rurales. No obstante, no existe suficiente evidencia sobre su impacto en la salud y la nutrición infantil. Objetivo: describir los cambios nutricionales de dos generaciones de hermanos(as) que han sido beneficiados por el programa Oportunidades en comunidades rurales de Chiapas. Métodos: estudio transversal. Se determinó: bajo peso, baja talla, emaciación y SP + O (Sobrepeso más Obesidad). Los hermanos(as) mayores fueron evaluados en los años 2002-2003, para el 2010-2011 se evaluaron a los hermanos( as) menores, ambos grupos eran < de 5 años de edad en el momento de conseguir la información. Resultados: la desnutrición en sus tres formas es un problema, 43,4% de los hermanos(as) evaluados(as) en 2010-2011 presentaron baja talla, la prevalencia de bajo peso disminuyó de 18% a 13,2%, la emaciación (peso bajo para la talla) aumentó de 8,1% a 10.4%. El SP + O aumentó significativamente 12 puntos porcentuales entre los hermanos(as) de 24,8% en 2002-2003 a 36,8% en 2010-2011. La desnutrición en los niños (varones) es menor que la de sus hermanos de la generación de 2002- 2003 (baja talla p =.

  20. [A very slow-growing exophytic hemisphere glioma: a case report].

    PubMed

    Velásquez, Carlos; Caballero, Hugo; Bucheli, Carlos; Berciano, José; Vázquez-Barquero, Alfonso; Martino, Juan

    2016-01-01

    Introduccion. Los gliomas de bajo grado presentan un patron de crecimiento caracteristico a traves de las fibras de la sustancia blanca. El crecimiento exofitico en gliomas de bajo grado hemisfericos no se ha descrito previamente. Se presenta un caso de glioma hemisferico de lenta progresion y con crecimiento exofitico. Caso clinico. Varon de 55 años, con crisis parciales motoras secundarias a un oligodendroglioma de grado II de la Organizacion Mundial de la Salud. El tumor infiltraba la circunvolucion frontal superior con extension exofitica que se extendia por encima de la circunvolucion precentral. Fue seguido con controles clinicorradiologicos durante 23 años. El analisis de la evolucion radiologica del tumor demostraba un crecimiento tumoral lento, con una velocidad de crecimiento de 0,5 mm al año. Durante la exeresis quirurgica se definio un plano subaracnoideo entre el componente exofitico y la circunvolucion precentral, que se encontraba desplazada inferiormente sin infiltracion tumoral. La estimulacion electrica intraoperatoria no evidencio funcion en el componente exofitico, pero si en la circunvolucion precentral. No se observaron deficits neurologicos postoperatorios. Conclusiones. La velocidad de crecimiento en gliomas de bajo grado se ha estimado en 4-6 mm al año. El tumor que se describe aqui tiene una velocidad de crecimiento de 0,5 mm al año, muy por debajo de esta media. La identificacion de la porcion exofitica es un paso importante en la planificacion preoperatoria. Este componente es mas facil de resecar debido al plano de clivaje subaracnoideo y a la ausencia de funcion.

  1. Effects of Seasonal Upwelling on Inorganic and Organic Matter Dynamics in the Water Column of Eastern Pacific Coral Reefs

    PubMed Central

    Stuhldreier, Ines; Sánchez-Noguera, Celeste; Rixen, Tim; Cortés, Jorge; Morales, Alvaro; Wild, Christian

    2015-01-01

    The Gulf of Papagayo at the northern Pacific coast of Costa Rica experiences pronounced seasonal changes in water parameters caused by wind-driven coastal upwelling. While remote sensing and open water sampling already described the physical nature of this upwelling, the spatial and temporal effects on key parameters and processes in the water column have not been investigated yet, although being highly relevant for coral reef functioning. The present study investigated a range of water parameters on two coral reefs with different exposure to upwelling (Matapalo and Bajo Rojo) in a weekly to monthly resolution over one year (May 2013 to April 2014). Based on air temperature, wind speed and water temperature, three time clusters were defined: a) May to November 2013 without upwelling, b) December 2013 to April 2014 with moderate upwelling, punctuated by c) extreme upwelling events in February, March and April 2014. During upwelling peaks, water temperatures decreased by 7°C (Matapalo) and 9°C (Bajo Rojo) to minima of 20.1 and 15.3°C respectively, while phosphate, ammonia and nitrate concentrations increased 3 to 15-fold to maxima of 1.3 μmol PO43- L-1, 3.0 μmol NH4+ L-1 and 9.7 μmol NO3- L-1. This increased availability of nutrients triggered several successive phytoplankton blooms as indicated by 3- (Matapalo) and 6-fold (Bajo Rojo) increases in chlorophyll a concentrations. Particulate organic carbon and nitrogen (POC and PON) increased by 40 and 70% respectively from February to April 2014. Dissolved organic carbon (DOC) increased by 70% in December and stayed elevated for at least 4 months, indicating high organic matter release by primary producers. Such strong cascading effects of upwelling on organic matter dynamics on coral reefs have not been reported previously, although likely impacting many reefs in comparable upwelling systems. PMID:26560464

  2. Mapping the Ancient Maya Landscape from Space

    NASA Technical Reports Server (NTRS)

    Sever, Tom

    2003-01-01

    This project uses new satellite and airborne imagery in combination with remote sensing, GIS, and GPS technology to understand the dynamics of how the Maya successfully interacted with their karst topographic landscape for several centuries in the northern Peten region of Guatemala. The ancient Maya attained one of the greatest population densities in human history in the tropical forest of the Peten, Guatemala, and it was in this region that the Maya civilization began, flourished, and abruptly disappeared for unknown reasons around AD 800. How the Maya were able to successfully manage water and feed this dense population is not known at this time. However, a recent NASA-funded project was the first to investigate large seasonal swamps (bajos) that make up 40 percent of the landscape. Through the use of remote sensing, ancient Maya features such as cities, roadways, canals and water reservoirs have been detected and verified through ground reconnaissance. The results of this research cast new light on the adaptation of the ancient Maya to their environment. Micro-environmental variation within the wetlands was elucidated and the different vegetational associations identified in the satellite imagery. More than 70 new archeological sites within and at the edges of the bajo were mapped and tested. Modification of the landscape by the Maya in the form of dams and reservoirs in the Holmul River and its tributaries and possible drainage canals in bajos was demonstrated. The recent acquisition of one-meter IKONOS imagery and high resolution STAR-3i radar imagery (2.5m backscatter/ 10m DEM), opens new possibilities for understanding how a civilization was able to survive for centuries upon a karst topographic landscape and their human-induced effects upon the local climate. This understanding is critical for the current population that is presently experiencing rapid population growth and destroying the landscape through non-traditional farming and grazing techniques

  3. Landscape Archeology: Remote Sensing Investigation of the Ancient Maya in the Peten Rainforest of Northern Guatemala

    NASA Technical Reports Server (NTRS)

    Sever, Thomas L.; Irwin, Daniel E.; Arnold, James E. (Technical Monitor)

    2002-01-01

    Through the use of airborne and satellite imagery we are improving our ability to investigate ancient Maya settlement, subsistence, and landscape modification in this dense forest region. Today the area is threatened by encroaching settlement and deforestation. However, it was in this region that the Maya civilization began, flourished, and abruptly disappeared for unknown reasons in the 9th century AD. At the time of their collapse they had attained one of the highest population densities in human history. How the Maya were able to successfully manage water and feed this dense population is not well understood at this time. A NASA-funded project used remote sensing technology to investigate large seasonal swamps (bajos) that make up 40 percent of the landscape. Through the use of remote sensing, ancient Maya features such as sites, roadways, canals and water reservoirs have been detected and verified through ground reconnaissance. The results of this preliminary research cast new light on the adaptation of the ancient Maya to their environment. Microenvironmental variation within the wetlands was elucidated and the different vegetation associations identified in the satellite imagery. More than 70 new archeological sites within and at the edges of the bajo were mapped and tested. Modification of the landscape by the Maya in the form of dams and reservoirs in the Holmul River and its tributaries and possible drainage canals in bajos was demonstrated. The use of Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM), one-meter IKONOS satellite imagery, as well as high resolution airborne STAR-3i radar imagery--2.5 meter backscatter/10 meter Digital Elevation Model (DEM)--are opening new possibilities for understanding how a civilization was able to survive for centuries upon a karat topographic landscape. This understanding is critical for the current population that is currently experiencing rapid population growth and destroying the landscape through

  4. Melt inclusions in veins: linking magmas and porphyry Cu deposits.

    PubMed

    Harris, Anthony C; Kamenetsky, Vadim S; White, Noel C; van Achterbergh, Esmé; Ryan, Chris G

    2003-12-19

    At a porphyry copper-gold deposit in Bajo de la Alumbrera, Argentina, silicate-melt inclusions coexist with hypersaline liquid- and vapor-rich inclusions in the earliest magmatic-hydrothermal quartz veins. Copper concentrations of the hypersaline liquid and vapor inclusions reached maxima of 10.0 weight % (wt %) and 4.5 wt %, respectively. These unusually copper-rich inclusions are considered to be the most primitive ore fluid found thus far. Their preservation with coexisting melt allows for the direct quantification of important oreforming processes, including determination of bulk partition coefficients of metals from magma into ore-forming magmatic volatile phases. PMID:14684818

  5. Soil and Human Interactions in Maya Wetlands

    NASA Astrophysics Data System (ADS)

    Beach, Timothy; Luzzadder-Beach, Sheryl

    2013-04-01

    Since the early 1990s, we have studied Maya interaction with soils in Mexico, Belize, Guatemala, and elsewhere. We studied upland and lowland soils, but here we focus on seasonal or 'Bajo' wetlands and perennial wetlands for different reasons. Around the bajos, the ancient Maya focused on intensive agriculture and habitation despite the difficulties their Vertisol soils posed. For the perennial wetlands, small populations spread diffusely through Mollisol and Histisol landscapes with large scale, intensive agro-ecosystems. These wetlands also represent important repositories for both environmental change and how humans responded in situ to environmental changes. Work analyzing bajo soils has recorded significant diversity but the soil and sediment record shows two main eras of soil instability: the Pleistocene-Holocene transition as rainfall fluctuated and increased and tropical forest pulsed through the region, and the Maya Preclassic to Classic 3000 to 1000 BP as deforestation, land use intensity, and drying waxed and waned. The ancient Maya adapted their bajo soil ecosystems successfully through agro-engineering but they also withdrew in many important places in the Late Preclassic about 2000 BP and Terminal Classic about 1200 BP. We continue to study and debate the importance of perennial wetland agro-ecosystems, but it is now clear that Maya interaction with these soil landscapes was significant and multifaceted. Based on soil excavation and coring with a broad toolkit of soil stratigraphy, chemistry, and paleoecology from 2001 to 2013, our results show the ancient Maya interacted with their wetland soils to maintain cropland for maize, tree crops, arrow root, and cassava against relative sea level rise, increased flooding, and aggradation by gypsum precipitation and sedimentation. We have studied these interactions across an area of 2000 km2 in Northern Belize to understand how Maya response varied and how these soil environments varied over time and distance

  6. Mapping The Ancient Maya Landscape From Space

    NASA Technical Reports Server (NTRS)

    Sever, Tom; Arnold, James E. (Technical Monitor)

    2002-01-01

    The Peten region of northern Guatemala is one of the last places on earth where major archeological sites remain to be discovered. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper and IKONOS satellite and airborne Star3-I radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as cities, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the bajos, which are seasonally flooded swamps that cover over 40% of the land surface. The use of bajos for farming has been a source of debate within the professional community for many years. But the recent detection and verification of cultural features within the bajo system by our research team are providing conclusive evidence that the ancient Maya had adapted well to wetland environments from the earliest times and utilized them until the time of the Maya collapse. The use of the bajos for farming is also an important resource for the future of the current inhabitants who are experiencing rapid population growth. Remote sensing imagery is also demonstrating that in the Preclassic period (600 BC- AD 250), the Maya had already achieved a high organizational level as evidenced by the construction of massive temples and an elaborate inter-connecting roadway system. Although they experienced several setbacks such as droughts and hurricanes, the Maya nevertheless managed the delicate forest ecosystem successfully for several centuries. However, around AD 800, something happened to the Maya to cause their rapid decline and eventual disappearance from the region. The evidence indicates that at this time there was increased climatic dryness, extensive deforestation, overpopulation, and widespread warfare. This raises a question that

  7. Recent Advances in Maya Studies Using Remotely Sensed Data

    NASA Technical Reports Server (NTRS)

    Sever, Tom; Irwin, Daniel; Arnold, James E. (Technical Monitor)

    2001-01-01

    The Peten region of northern Guatemala is one of the last places on earth where major archeological sites remain to be discovered. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper and IKONOS satellite and airborne Star3i radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as cities, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the bajos, which are seasonally flooded swamps that cover over 40% of the land surface. The use of baJos for farming has been a source of debate within the professional community for many years. But the recent detection and verification of cultural features within the baJo system by our research team are providing conclusive evidence that the ancient Maya had adapted well to wetland environments from the earliest times and utilized them until the time of the Maya collapse. The combination of water management and baJo farming is an important resource for the future of the current inhabitants who are experiencing rapid population growth. Remote sensing imagery is also demonstrating that in the Preclassic period (600 BC- AD 250), the Maya had already achieved a high organizational level as evidenced by the construction of massive temples and an elaborate inter-connecting roadway system. Although they experienced several setbacks such as droughts and hurricanes, the Maya nevertheless managed the delicate forest ecosystem successfully for several centuries. However, around AD 800, something happened to the Maya to cause their rapid decline and eventual disappearance from the region. The evidence indicates that at this time there was increased climatic dryness, extensive deforestation, overpopulation, and widespread warfare. This raises a

  8. Bases para la elaboracion de unidades didacticas de calidad en el area de ciencias (Fisica y Quimica 3 deg ESO)

    NASA Astrophysics Data System (ADS)

    Maccioni, Elena Lucia

    Este Trabajo Fin de Master tiene como objeto, el estudio previo de la educacion de la ciencia en la actualidad y mas destacable, del diseno de las unidades didacticas segun las metodologias mas frecuentes aplicadas por los diferentes sistemas educativos en el area de las Ciencias teniendo en cuenta la importancia y el efecto de la psicologia del alumnado y todo ello como no puede ser de otro modo bajo el corse de la Legislacion aplicable, Estatal, Autonomica y europea. Con estos antecedentes, se extrae cuales son las preguntas que deben contestarse en la elaboracion de una unidad didactica de calidad en el contexto, generacional (edad y sexo), del Proyecto Educativo de Centro, y de la Programacion del Departamento, discutiendo y justificando cada uno de los apartados en que estructuradamente dividiremos dicha Unidad, con un formato manejable, util, y dinamico en el tiempo que sea un verdadero instrumento educativo de aula. Teniendo en cuenta estas premisas, se procede a hacer una recopilacion de una misma unidad didactica publicada por diferentes editoriales, elegidas no al azar, sino en funcion de su penetracion editorial en nuestros centros de ESO, siendo las elegidas (SM y Oxford). Las diferentes unidades seleccionadas son analizadas de forma critica, atendiendo a los criterios generales de calidad bajo parametros cientificos y normativos, concluyendo con la aportacion final que es la redaccion de unas pautas cientifico-pedagogicas, para redactar unidades didacticas de calidad en el area de la Ciencias, en concreto en la Asignatura de Fisica y Quimica de 3º de ESO.

  9. [Educational status and life expectancy in patients with chronic non-communicable diseases].

    PubMed

    Villarreal-Hernández, Liliana del Sagrario; Romo-Martínez, Jesús Eduardo

    2014-01-01

    INTRODUCCIÓN: una enfermedad crónica no transmisible, el nivel educativo bajo y los bajos ingresos económicos pueden hacer sinergia y contribuir a un mal pronóstico en cuanto a la expectativa de vida esperada. Se estima que alcanzar un mejor nivel de educación hace posible que mejore la expectativa de vida. El objetivo de esta investigación fue explorar esta relación. MÉTODOS: estudio de cohorte retrospectivo realizado del 1 de enero de 1999 al 31 de diciembre de 2011, de individuos que fallecieron por enfermedades crónicas no transmisibles. Se incluyeron 2306 pacientes registrados en el Sistema de Información en Mortalidad de la Unidad de Medicina Familiar 3, Instituto Mexicano del Seguro Social, en Guadalajara, Jalisco. Se registró la edad al momento de la muerte y el nivel educativo. Las pruebas estadísticas aplicadas fueron t de Student y 2. Se calculó el riesgo relativo.

  10. [In Process Citation].

    PubMed

    Durán Agüero, Samuel; Herrera Valenzuela, Tomás; Poblete Aro, Carlos; Durán Acevedo, Angelo; Valdés Badilla, Pablo

    2016-03-25

    Objetivo: determinar los patrones alimentarios de ultramaratonistas chilenos. Métodos: estudio descriptivo transversal, con enfoque cuantitativo. La muestra incluyó 20 ultramaratonistas (n = 3 mujeres), quienes promediaban para la edad 33,0 ± 7,8 años, peso 71,1 ± 6,6 kg y estatura 1,72 ± 0,05 m. Se aplicó una encuesta de hábitos alimentarios validada y un punto de significación de p < 0,05. Resultados: los ultramaratonistas chilenos presentan bajo consumo de alimentos de acuerdo a las porciones recomendadas de frutas, verduras, pescado y leguminosas, y el 75% de ellos consume desayuno diariamente. Se observa ingestas moderadas de bebidas azucaradas, snacks dulces y alcohol, mientras que la ingesta de frituras (65%) corresponde al hábito no saludable más frecuente. Conclusión: los ultramaratonistas chilenos presentan un bajo cumplimiento en las porciones recomendadas de alimentos, pese al gran esfuerzo físico que realizan.

  11. [In Process Citation].

    PubMed

    Durán Agüero, Samuel; Herrera Valenzuela, Tomás; Poblete Aro, Carlos; Durán Acevedo, Angelo; Valdés Badilla, Pablo

    2016-01-01

    Objetivo: determinar los patrones alimentarios de ultramaratonistas chilenos. Métodos: estudio descriptivo transversal, con enfoque cuantitativo. La muestra incluyó 20 ultramaratonistas (n = 3 mujeres), quienes promediaban para la edad 33,0 ± 7,8 años, peso 71,1 ± 6,6 kg y estatura 1,72 ± 0,05 m. Se aplicó una encuesta de hábitos alimentarios validada y un punto de significación de p < 0,05. Resultados: los ultramaratonistas chilenos presentan bajo consumo de alimentos de acuerdo a las porciones recomendadas de frutas, verduras, pescado y leguminosas, y el 75% de ellos consume desayuno diariamente. Se observa ingestas moderadas de bebidas azucaradas, snacks dulces y alcohol, mientras que la ingesta de frituras (65%) corresponde al hábito no saludable más frecuente. Conclusión: los ultramaratonistas chilenos presentan un bajo cumplimiento en las porciones recomendadas de alimentos, pese al gran esfuerzo físico que realizan. PMID:27238804

  12. Amplificadores en bandas para receptores de uso radioastronómicos

    NASA Astrophysics Data System (ADS)

    Bava, A. J.; Sanz, A. J.

    Está en curso de realización en el IAR un cabezal de receptor, en la frecuencia de 3.3 GHz. Este receptor, conjuntamente con los sistemas de procesamientos actuales del IAR y con los futuros proyectos de procesamientos, permitirán las observaciones de las líneas de la molécula de CH, de gran interés astrofísico, y las observaciones en el continuo que complementarán las realizadas en 1420 MHz. En este trabajo, se presentan el diseño de los amplificadores de bajo ruido, que van a conformar las primeras etapas del receptor de 3.3 GHz. El desarrollo de los mismos se realizó teniendo en cuenta que la temperatura del sistema, según consideraciones observacionales, deberá ser de 60oK. Por tal motivo se realizó un diseño de bajo ruido utilizando como elemento activo un HEMT. Tanto los métodos de diseño, como el circuito final, fueron realizados y comprobados con programas de simulación, permitiendo de esta forma obtener el amplificador deseado.

  13. An analysis of modern pollen rain from the Maya lowlands of northern Belize

    USGS Publications Warehouse

    Bhattacharya, T.; Beach, T.; Wahl, D.

    2011-01-01

    In the lowland Maya area, pollen records provide important insights into the impact of past human populations and climate change on tropical ecosystems. Despite a long history of regional paleoecological research, few studies have characterized the palynological signatures of lowland ecosystems, a fact which lowers confidence in ecological inferences made from palynological data. We sought to verify whether we could use pollen spectra to reliably distinguish modern ecosystem types in the Maya lowlands of Central America. We collected 23 soil and sediment samples from eight ecosystem types, including upland, riparian, secondary, and swamp (bajo) forests; pine savanna; and three distinct wetland communities. We analyzed pollen spectra with non-metric multidimensional scaling (NMDS), and found significant compositional differences in ecosystem types' pollen spectra. Forested sites had spectra dominated by Moraceae/Urticaceae pollen, while non-forested sites had significant portions of Poaceae, Asteraceae, and Amaranthaceae pollen. Upland, bajo, and riparian forest differed in representation of Cyperaceae, Bactris-type, and Combretaceae/Melastomataceae pollen. High percentages of pine (Pinus), oak (Quercus), and the presence of Byrsonima characterized pine savanna. Despite its limited sample size, this study provides one of the first statistical analyses of modern pollen rain in the Maya lowlands. Our results show that pollen assemblages can accurately reflect differences between ecosystem types, which may help refine interpretations of pollen records from the Maya area. ?? 2010 Elsevier B.V.

  14. [Dietary factors associated with stroke: a literature review].

    PubMed

    Lopez-Romero, L; Silva-Sieger, F; Gamboa-Delgado, E

    2016-09-01

    Introduccion. El ictus es una condicion cronica no transmisible de alto impacto, producida por diferentes factores, entre los que estan los relacionados con el estilo de vida, de los cuales forman parte los factores dieteticos. Objetivo. Revisar la evidencia existente con relacion a los factores dieteticos asociados al ictus. Desarrollo. Se realizo una revision de la bibliografia de los factores dieteticos y el ictus. Los estudios revisados describen una disminucion del riesgo de ictus, segun el consumo recomendado, hasta del 39% para la dieta mediterranea, el 19% para la dieta DASH, el 10% para las nueces, el 26% para las frutas y verduras, el 31% para el pescado, el 26% para la proteina total, el 9% para los lacteos bajos en grasa y el 18% para el calcio. Por el contrario, describen un aumento del riesgo hasta del 58% para la dieta occidental, el 13% para la carne procesada y el 23% para la sal. En relacion con el consumo de legumbres, huevos y leche entera, los resultados son heterogeneos. Conclusiones. El consumo de nueces, frutas y verduras, pescado, proteina total, lacteos bajos en grasa, calcio y la alta adhesion a las dietas DASH y mediterranea podrian tener efectos protectores para el ictus. Mientras que el alto consumo de carnes rojas y procesadas, sal y la dieta occidental podrian constituir un factor de riesgo. Asimismo, es necesaria una mayor investigacion en relacion con el consumo de legumbres, huevos, leche entera, arroz, patatas y bebidas azucaradas.

  15. Habitus furibundo en el gueto estadounidense1

    PubMed Central

    Bourgois, Philippe; Castrillo, Fernando Montero; Hart, Laurie; Karandinos, George

    2014-01-01

    Resumen Durante cinco años, un torbellino cotidiano de tiroteos, apuñalamientos y asaltos afectó a la venta de drogas al aire libre en el vecindario puertorriqueño de Filadelfia, donde residíamos y conducíamos nuestro trabajo de campo. La industria de los narcóticos ha venido a llenar el vacío que dejó la desindustrialización, convirtiendo al antiguo distrito fabril de la ciudad en un mercado de narcóticos a cielo abierto que emplea en sus niveles más bajos a jóvenes puertorriqueños y cuyos clientes son principalmente heroinómanos blancos de bajos recursos. La capacidad para movilizar la furia asegura el éxito en la economía de las drogas, garantiza protección en las cárceles y le provee un ingreso mínimo a una población de bajos recursos estigmatizada cuyos miembros frecuentemente reciben diagnósticos médicos de discapacidad cognitiva. Muchos residentes buscan alianzas en redes sociales que los comprometen a participar en intercambios solidarios de violencia auxiliar. Una dinámica de acumulación primitiva corporizada mata, hiere, discapacita o encarcela a la mayoría de estos empleados de bajo nivel y a sus clientes. Los inflados márgenes de ganancia alrededor de esta dinámica dependen de la violencia y la coerción. Un habitus furibundo impulsa a los vendedores callejeros a defender violentamente el micro monopolio de poder de sus jefes en la economía subterránea como si fuese un asunto de diversión. Estos miembros de los niveles más bajos de la industria del narcotráfico se apresuran a fraguar transacciones comerciales en ausencia de un marco legal en un ambiente de escasez que sin embargo se ve inundado por enormes flujos de dinero, drogas adictivas y armas automáticas. Tras las drásticas reformas a los programas de seguridad social, la mano izquierda del Estado, en la forma de los servicios sociales, intenta prolongar los subsidios para individuos vulnerables diagnosticándolos como discapacitados cognitivos permanentes

  16. Evidence for Repeated Early Miocene Glaciation and the Cutting of Upper Taylor Valley from the Friis Hills, Antarctica

    NASA Astrophysics Data System (ADS)

    Lewis, A.; Ashworth, A. C.; Marchant, D. R.; Hemming, S. R.

    2009-12-01

    The Friis Hills, located at the head of Taylor Valley in the the McMurdo Dry Valleys, hold a sequence of stacked tills at least Early Miocene in age. Sedimentology, clast lithology and bedrock striations indicate these tills were deposited from wet-based glaciers that flowed southeastward down a shallow paleovalley toward the Ferrar trough. Interbedded paleosols, fluvial, and glaciolacustrine deposits register ice-free periods when the valley held small streams and ponds. Exceptionally well-preserved fossil biota suggests mild conditions during at least two of these interglacial episodes. Proglacial lacustrine deposits that include dropstones and debris flows mark the return of glacial conditions but fossil leaves and wood of Nothofagus suggest conditions during the initial phase of ice advance were also relatively mild. Geomorphic relationships show that major valley incision must have taken place after deposition of these sediments as the Friis Hills is today a flat-topped inselberg, about 5 km across, isolated from nearby topography by the deep glacial troughs of the Taylor Valley drainage. A second suite of tills, directly overlying the first, registers a reorganized glacial system with ice streaming eastward, roughly parallel to Taylor Valley. Like the first, these tills were deposited during repeated ice advances but glaciers never fully inundated the Friis Hills and ice-free periods are marked by only weak weathering surfaces and thin glaciolacustrine deposits. We interpret the changing glacial pattern to reflect headward cutting in upper Taylor Valley and the capture of ice from the Ferrar drainage. A volcanic ash interbed dated by Ar-Ar at 19.76 (±0.11) Ma occurs in a Taylor Valley-oriented drift near the eastern edge of the Friis Hills plateau. Based on its stratigraphic position, the older suite of tills and fossil-bearing interbeds are >19.76 Ma. Underlying bedrock striations show that ice flow had been redirected into Taylor Valley by this time. The

  17. The influence of production conditions, starting material and deposition environment on charcoal alteration in a tropical biome.

    NASA Astrophysics Data System (ADS)

    Ascough, Philippa; Bird, Michael; Meredith, Will; Large, David; Snape, Colin; Manion, Corinne

    2014-05-01

    Natural and anthropogenic burning events are a key link in the global carbon cycle, substantially influencing atmospheric CO2 levels, and consuming c.8700 teragrams yr-1 of dry biomass [1,2,3]. An important result of this process is charcoal, when lignocellulosic structures in biomass (e.g. wood) are converted to aromatic domains with high chemical stability. Charcoal is therefore not readily re-oxidized to CO2, with estimates of 5-7 ky for the half-life of charcoal carbon in soils [3,4]. Charcoal's high carbon content coupled with high environmental resistance has led to the concept of biochar as a valuable means of global carbon sequestration, capable of carbon offsets comparable to annual anthropogenic fuel emissions [5,6,7]. Charcoal is not, however, an environmentally inert substance, and at least some components of charcoal are susceptible to alteration in depositional environments. Despite the importance of charcoal in global carbon cycling, the mechanisms by which charcoal is altered in the environment remain, as yet, poorly understood. This fact limits our ability to properly incorporate both natural environmental charcoal and biochar into global carbon budgets. This study aimed to improve understanding of charcoal alteration in the environment by examining the influence of production conditions, starting material and deposition environment on the physical and chemical characteristics of charcoal at a field site in the Daintree rainforest. These factors have been identified as critical in determining the dynamics of charcoal in depositional environments [8,9] and climatic conditions at the field site (in Tropical Queensland, Australia) are likely to result in extensive alteration of charcoal. Charcoal from wood (Nothofagus spp.), algae (Enteromorpha spp.), and sugarcane (Saccharum spp.) biomass was produced at temperatures over 300-500°C and exposed to conditions of varying pH and vegetation cover. The effect of these variables on charcoal chemistry

  18. A Glimpse at Late Mesozoic to Early Tertiary Offshore Stratigraphy from Wilkes Land, East Antarctica: Results of Strategic Dredging of the Mertz-Ninnis Trough

    NASA Astrophysics Data System (ADS)

    Schrum, H.; Domack, E.; Desantis, L.; Leventer, A.; McMullen, K.; Escutia, C.

    2004-12-01

    As early as 1912 Sir Douglas Mawson demonstrated that pre-glacial sedimentary successions could be recovered by seafloor dredging of erosional troughs found offshore, East Antarctica. Since then, little systematic dredging has been undertaken in Antarctica despite indications of outcropping strata exposed along seaward flanks of glacially excavated troughs and the dire need to resolve the nature of preglacial and synglacial strata in this region. During cruise NB Palmer 01-01, three dredges were collected in echelon along the seaward flank of the Mertz-Ninnis Trough, parallel to the Mertz Ice Tongue, in water depths of 900 to 450 m. We combine biostratigraphic (palynologic) and lithologic analyses on sedimentary clasts with multi- and single-channel seismic reflection data collected by the WEGA cruise in 2000. 1359 pebble to cobble sized clasts were collected from three dredges. Of these 15% to 43%, within each dredge, were of sedimentary character, including carbonaceous sandstones with plant macrofossils, black sulfide-rich mudstones, siltstones, lignites, red quartz arenites, arkoses, and diamictites in various states of lithification. Palynomorphs were separated from these sedimentary rocks. We examined eleven individual lithologies, nine of which yielded useful palynological detritus. Of these samples, five yielded palynomorphs distinctive to the Paleogene (i.e. Nothofagus flemingii, Tricolporites spp., Proteacidites spp.); two samples contained only Lower Cretaceous palynomorphs, while three samples provided no stratigraphically useful palynomorph kerogen. We combine these results with multi-channel seismic and multibeam swath mapping to demonstrate that dredged materials represent seafloor outcrop or shallow subcrop of strata beneath a thin glacial till. Our stratigraphic model for these samples is consistent with 62 km of multichannel seismic reflection data (WEGA line W02) showing seaward dipping strata onlapping the basement to the southwest and partly

  19. Abundance and Morphological Effects of Large Woody Debris in Forested Basins of Southern Andes

    NASA Astrophysics Data System (ADS)

    Andreoli, A.; Comiti, F.; Lenzi, M. A.

    2006-12-01

    The Southern Andes mountain range represents an ideal location for studying large woody debris (LWD) in streams draining forested basins thanks to the presence of both pristine and managed woodland, and to the general low level of human alteration of stream corridors. However, no published investigations have been performed so far in such a large region. The investigated sites of this research are three basins (9-13 km2 drainage area, third-order channels) covered by Nothofagus forests: two of them are located in the Southern Chilean Andes (the Tres Arroyos in the Malalcahuello National Reserve and the Rio Toro within the Malleco Natural Reserve) and one basin lies in the Argentinean Tierra del Fuego (the Buena Esperanza basin, near the city of Ushuaia). Measured LWD were all wood pieces larger than 10 cm in diameter and 1 m in length, both in the active channel and in the adjacent active floodplain. Pieces forming log jams were all measured and the geometrical dimensions of jams were taken. Jam type was defined based on Abbe and Montgomery (2003) classification. Sediment stored behind log-steps and valley jams was evaluated approximating the sediment accumulated to a solid wedge whose geometrical dimensions were measured. Additional information relative to each LWD piece were recorded during the field survey: type (log, rootwad, log with rootwads attached), orientation to flow, origin (floated, bank erosion, landslide, natural mortality, harvest residuals) and position (log-step, in-channel, channel-bridging, channel margins, bankfull edge). In the Tres Arroyos, the average LWD volume stored within the bankfull channel is 710 m3 ha-1. The average number of pieces is 1,004 per hectare of bankfull channel area. Log-steps represent about 22% of all steps, whereas the elevation loss due to LWD (log-steps and valley jams) results in 27% loss of the total stream potential energy. About 1,600 m3 of sediment (assuming a porosity of 20%) is stored in the main channel

  20. Enhanced Southern Westerly Activity During the Last Glacial Interglacial Transition in SW Patagonia

    NASA Astrophysics Data System (ADS)

    Moreno, P. I.; Villa-Martinez, R. P.; Cardenas, M. L.; Moy, C. M.

    2008-12-01

    Much of the ongoing controversy regarding synchrony or bipolar asynchrony has centered on the timing and structure of temperature changes during the Last Glacial Interglacial Transition (LGIT) in the southern mid- latitudes, in particular the Patagonian region (40°-56°S) of South America. South America is the only continuous continental landmass in the Southern Hemisphere that intersects the entire westerly wind belt and lies in the critical climatic interface between mid- to high latitudes. The region between 50°- 55°S is of particular interest considering its proximity to the polar front and the southern margin of the westerly winds, and the possibility of monitoring paleoclimate changes at or near this important oceanic- atmospheric boundary. Present and past climate studies, including modeling simulations, have emphasized that interactions between changes in the Antarctic Circumpolar Current, the southern westerly winds, sea ice, and the polar front are important drivers for deep ocean circulation changes, variations in atmospheric CO2, and equator-to-pole temperature and pressure gradients. Yet, the behavior of the westerly winds and the adjacent Southern Ocean during the LGIT is still poorly understood despite their fundamental influence on modern hemispheric and global climate. In this study we compare sediment cores from small closed-basin lakes and a bog from the Ultima Esperanza area of SW Patagonia (52°S), an area affected solely by the southern westerlies. Lake sediment cores from three lakes show lacustrine sedimentation over the last 17,000 years. In contrast, the Dumestre bog shows subaerial peat deposition since 15 ka interrupted by a prominent lacustrine phase dated between 14.5-11.5 ka. During this interval palynological records indicate the preponderance of cold-resistant herbs, along with aquatic taxa, followed by a rapid expansion of Nothofagus woodlands/forests, a lake regressive phase in Dumestre, and disappearance of laminated calcite

  1. Towards a common methodology to simulate tree mortality based on ring-width data

    NASA Astrophysics Data System (ADS)

    Cailleret, Maxime; Bigler, Christof; Bugmann, Harald; Davi, Hendrik; Minunno, Francesco; Peltoniemi, Mikko; Martínez-Vilalta, Jordi

    2015-04-01

    Individual mortality is a key process of population and community dynamics, especially for long-lived species such as trees. As the rates of vegetation background mortality and of massive diebacks accelerated during the last decades and would continue in the future due to rising temperature and increasing drought, there is a growing demand of early warning signals that announce that the likelihood of death is very high. If physiological indicators have a high potential to predict tree mortality, their development requires an intensive tree monitoring which cannot be currently done on a representative sample of a population and on several species. An easier approach is to use radial growth data such as tree ring-widths measurements. During the last decades, an increasing number of studies aimed to derive these growth-mortality functions. However, as they followed different approaches concerning the choice of the sampling strategy (number of dead and living trees), of the type of growth explanatory variables (growth level, growth trend variables…), and of the length of the time-window (number of rings before death) used to calculate them, it makes difficult to compare results among studies and a subsequent biological interpretation. We detailed a new methodology for assessing reliable tree-ring based growth-mortality relationships using binomial logistic regression models. As examples we used published tree-ring datasets from Abies alba growing in 13 different sites, and from Nothofagus dombeyi and Quercus petraea located in one single site. Our first approach, based on constant samplings, aims to (1) assess the dependency of growth-mortality relationships on the statistical sampling scheme used; (2) determine the best length of the time-window used to calculate each growth variable; and (3) reveal the presence of intra-specific shifts in growth-mortality relationships. We also followed a Bayesian approach to build the best multi-variable logistic model considering

  2. Heavy metals, arsenic, and pesticide contamination in an area with high incidence of chronic kidney disease of non-traditional causes in El Salvador

    NASA Astrophysics Data System (ADS)

    Lopez, D. A.; Ribó, A.; Quinteros, E.; Mejia, R.; Jovel, R.; VanDervort, D.; Orantes, C. M.

    2013-12-01

    Chronic kidney disease of non-traditional causes is epidemic in Central America, Southern Mexico and other regions of the world such as Sri Lanka, where the origin of the illness is attributed to exposure to agrochemicals and arsenic in soils and groundwater. In Central America, several causes have been suggested for this illness including: high ambient temperatures and chronic dehydration, and toxic effects of agrochemicals. Previous research using step-wise multivariate regression in El Salvador found statistically significant correlation between the spatial distribution of the number of sick people per thousand inhabitants and the percent area cultivated with sugar cane, cotton, and beans, and maximum ambient temperature, with sugar cane cultivation as the most significant factor. This study aims to investigate the possible effects of agricultural activities in the occurrence of this illness looking at heavy metal, arsenic and pesticide contamination in soil, water and sediments of a community located in Bajo Lempa region (Ciudad Romero, El Salvador) and heavily affected by this illness. The Bajo Lempa region is close to Lempa River delta, in the Pacific coast. Ground and surface water, sediment and soil samples were collected in the village where the patients live and in the agricultural areas where they work. With respect to the heavy metals, lead and cadmium where detected in the soils but below the standards for cultivated soils, however, they were not detected in the majority of surface and groundwater. Of the inorganic contaminants, arsenic was present in most soil, sediments, and water samples with some concentrations considerable higher than the standards for cultivated lands and drinking water. Statistically different concentrations in soils were found for the village soils and the cultivated soils, with arsenic higher in the cultivated soils. For the pesticides, results show a significant pollution of soil and groundwater of organochlorine pesticides

  3. UNDERNUTRITION, SERUM VITAMIN B12, FOLIC ACID AND DEPRESSIVE SYMPTOMS IN OLDER ADULTS.

    PubMed

    Brito Noronha, Mafalda; Almeida Cunha, Nathalie; Agra Araújo, Daniela; Flamínio Abrunhosa, Sofia; Nunes Rocha, Ada; Freitas Amaral, Teresa

    2015-07-01

    Antecedentes: la cuestión del posible vínculo entre la desnutrición y los síntomas depresivos, considerando el efecto de las deficiencias de vitamina B12 y de folato, es de importancia práctica porque estas son potencialmente prevenibles y tratables. Este estudio tiene como objetivo evaluar si la desnutrición está relacionada con los síntomas depresivos, teniendo en cuenta el efecto de los niveles plasmáticos de vitamina B12 y de folato. Método: un estudio transversal se llevó a cabo en una muestra de 84 adultos mayores que viven en hogares de cuidado. Se obtuvieron datos sobre el estado nutricional utilizando Mini-Nutritional Assessment, los niveles séricos de ácido fólico y vitamina B12, la capacidad cognitiva, la dependencia funcional, y/o los síntomas de comportamiento depresivo. Los síntomas de depresión se midieron utilizando la versión de 20 ítems de la Escala de Depresión del Centro de Estudios Epidemiológicos. Resultados: cincuenta y tres adultos mayores estaban en riesgo de depresión (63,1%). De ellos, el 34% estaban en riesgo de desnutrición. Aunque se encontró una alta frecuencia de adultos mayores con bajos niveles plasmáticos de vitamina B12 (42,9%) y niveles más bajos de ácido fólico (5,9%), no se encontraron diferencias significativas en relación con la existencia de síntomas depresivos. En el análisis multivariable se observó un aumento en el riesgo de depresión entre los participantes con riesgo nutricional OR = 3,47 (1,05 a 11,46), mientras tener bajos niveles de ácido fólico y vitamina B12 no se asociaron con el riesgo de depresión. Conclusión: entre los adultos mayores desnutridos se observó un aumento en el riesgo de depresión, independientemente del ácido fólico y del estado de la vitamina B12. Estos resultados ponen de manifiesto la necesidad de implementar estrategias preventivas, especialmente dirigidas a los adultos mayores que viven en hogares de cuidado.

  4. Impact of an intervention nutrition program during prenatal on the weight of newborns from teenage mothers.

    PubMed

    Santos, Marta Maria Antonieta de Souza; Cavalcante de Barros, Denise; Lima Nogueira, Jamile; Ribeiro Baião, Miriam; Saunders, C

    2013-11-01

    Introducción: La atención nutricional a la adolescente embarazada se ha estudiado como un factor que influye en la evolución de los resultados del embarazo y neonatales, especialmente en el peso al nacer. Objetivo: Evaluar el efecto de un programa de intervención nutricional prenatal, con inicio temprano de la asesoría nutricional y seguimiento individualizado, sobre el peso de los recién nacidos de madres adolescentes. Métodos: Estudio de intervención no aleatorio con 746 adolescentes embarazadas (14 a 19 años), subdivididas entre grupo de control histórico (GI; n= 542) y grupo de intervención (GII; n= 204). La variable dependiente fue el bajo peso al nacer (BPN). Las variables independientes evaluadas fueron: sociodemográfica (edad materna, color de piel, nivel educacional y condiciones de saneamiento), antropométricas (altura, situación nutricional previa a la gestación adecuación incremento de peso en la gestación), obstétricas (edad gestacional en la primera consulta prenatal, número de embarazos, nacimientos y abortos, intervalo entre nacimientos y gestaciones), de la atención prenatal (número de citas médicas prenatales y citas de asistencia nutricional) y las condiciones del recién nacido (peso al nacer y la duración del embarazo). Los datos fueron analizados por regresión de Poisson con varianza robusta. Resultados: La edad materna promedio al nacer fue de 17,5 años (desviación estándar 1.59). El porcentaje de BPN sufrió una reducción significativa de 11,3% en GI a 2,9% en GII (p < 0,001). El modelo multivariado mostró que las adolescentes embarazadas que no recibieron la intervención mostraron 3,5 veces más alta prevalencia (GI RP ajustada 3,5; IC 95% 1,49-8,44) de dar a luz a un recién nacido de bajo peso. Conclusión: La investigación concluye que la participación de adolescentes embarazadas en un programa de atención nutricional prenatal contribuye a la reducción del bajo peso al nacer en sus descendientes.

  5. [Efficacy and effectiveness of different nutritional screening tools in a tertiary hospital].

    PubMed

    Calleja Fernández, Alicia; Vidal Casariego, Alfonso; Cano Rodríguez, Isidoro; Ballesteros Pomar, María D

    2015-05-01

    Introducción: La elevada prevalencia de desnutrición en el medio hospitalario y sus repercusiones hacen necesario el empleo de herramientas de cribado nutricional para su detección, diagnóstico y tratamiento precoz. Objetivo: Evaluar la herramienta de cribado nutricional más adecuada para el paciente hospitalizado en un hospital de tercer nivel, a nivel global y por servicios de hospitalización. Metodología: Estudio transversal realizado en condiciones de práctica clínica habitual. Se evaluaron 4 métodos de cribado nutricional: Valoración Subjetiva Global (VSG), Mini Nutritional Assessment (MNA), Malnutrition Universal Screening Tool (MUST) y Nutritional Risk Screening 2002 (NRS-2002). Los servicios de hospitalización se agruparon en: servicios médicos, Cirugía General, Traumatología, otros servicios quirúrgicos y Oncología-Hematología. Se realizó un análisis estadístico de sensibilidad (S) y especificidad (Sp) y fueron comparados mediante curva COR. Resultados: Fueron valorados 201 pacientes con mediana de edad de 71,6 (RIC 21,4) años y el 51,2% fueron mujeres. La prevalencia de riesgo nutricional (RN) y desnutrición (DN) detectada fue: VSG 62,1%, MNA 68,6%, MUST 53,7% y NRS-2002 35,8%. Con todas las herramientas de cribado nutricional, excepto el MNA, se detectó una mayor prevalencia de RN y DN en los servicios médicos y quirúrgicos. En el análisis global el MNA obtuvo una S =93,3%, una Sp = 71,6% y un área bajo la curva COR de 0,825; el MUST obtuvo una S = 82,4%, una Sp = 93,4% y un área bajo la curva COR de 0,879; el NRS-2002 obtuvo una S = 56,0%, una Sp = 97,4% y un área bajo la curva COR de 0,766. Estos resultados fueron similares en el análisis por servicios de hospitalización. Conclusión: La herramienta de cribado nutricional recomendada en un centro hospitalario de tercer nivel y población envejecida sería el MUST por los adecuados resultados de sensibilidad y especificidad y la facilidad en su realización.

  6. HIGH BODY MASS INDEX AMONG PATIENTS UNDERGOING HEMATOPOIETIC STEM CELL TRANSPLANTATION: RESULTS OF A CROSS-SECTIONAL EVALUATION OF NUTRITIONAL STATUS IN A PRIVATE HOSPITAL.

    PubMed

    Pereira, Andrea Z; Victor, Elivane S; Vidal Campregher, Paulo; Piovacari, Silvia M F; Bernardo Barban, Juliana S; Pedreira, Wilson L; Hamerschlak, Nelson

    2015-12-01

    Introducción: el estado nutricional previo al trasplante de células madre hematopoyéticas (HSCT) afecta al pronóstico: los pacientes con una mejor nutrición necesitan un menor tiempo de injerto, mientras que una nutrición pobre estaría asociada a un aumento de la tasa de mortalidad, complicaciones, costes médicos, mala calidad de vida y hospitalización. Además, los pacientes con bajo peso presentan un mayor riesgo de muerte al principio del periodo post-HSCT, y la tasa de mortalidad sin recaída es mayor en aquellos con bajo peso extremo, sobrepeso y obesidad. La obesidad está relacionada con una toxicidad asociada al tratamiento, una incidencia más alta de enfermedad de injerto-huésped de grado II-IV (GVHD), infecciones y mortalidad. El objetivo de este estudio fue investigar el estado nutricional de pacientes que se sometieron a HSCT entre 2007 y 2013 en un hospital privado, calculando el índice de masa corporal (IMC), para comprobar la prevalencia de posibles desajustes nutricionales, especialmente obesidad. Métodos: en este estudio retrospectivo, basado en informes médicos, analizamos datos de todos los pacientes con enfermedades tumorales y no tumorales que se sometieron a HSCT desde enero de 2007 hasta febrero de 2014 en el Centro de hematología-oncología y trasplante de médula ósea en un gran centro de especialidades médicas en Brasil. Resultados: en el periodo se trató y analizó un total de 257 casos, de los cuales el 79% tenían edades de hasta 65 años. Entre estos, el 56% tenían sobrepeso u obesidad. Observamos una mayor prevalencia de obesidad en pacientes ancianos (P < 0,001). El IMC medio de la muestra total fue 26,4 kg/m2. El IMC fue significativamente diferente entre géneros, con una prevalencia mayor de sobrepeso entre los hombres (P < 0,001). Conclusión: a diferencia de otros estudios, nuestra investigación ha mostrado bajas tasas de tasas de bajo peso y altas tasas de sobrepeso y de obesidad en los hombres y pacientes

  7. Prevalence of factors related to the bone mass formation of children from a cohort in Southern Brazil.

    PubMed

    Doumid Borges Pretto, Alessandra; Correa Kaufmann, Cristina; Ferreira Dutra, Gisele; Pinto Albernaz, Elaine

    2014-12-17

    Introducción: La cantidad de masa ósea adquirida en las primeras etapas de la vida es un importante factor determinante de su pico y el riesgo futuro de osteoporosis y fracturas. Objetivo: Describir la prevalencia de factores que contribuye a la formación de la masa ósea en niños de una cohorte del sur de Brasil. Métodos: Estudio de cohorte retrospectiva con el hospital de todos los nacimientos (2741) se produjo en septiembre / 2002 a mayo / 2003 y el seguimiento de una muestra aleatoria de un 30,0% de los mismos (uno, tres y seis meses y ocho años de edad). En una visita a los ocho años de edad, aplicó un cuestionario con preguntas relacionadas con la alimentación y la actividad física. Resultados y Discusión: De los 616 niños, el 51,3% eran hombres, el 70,3% de raza caucásica, cerca de la mitad pertenecían a la clase económica C, 20,5% tenían sobrepeso, el 16,9% eran obesos y 71,2% sedentarios. La ingesta de alimentos es bajo consumo de frutas, verduras, productos lácteos, carne, los cereales y los tubérculos. La administración de vitamina D en los primeros seis meses de vida fue seguido por 14,1% de los prematuros, el 16,1% de los recién nacidos con bajo peso al nacer, el 24,2% de destete en el primer mes y sólo el 16,4% a los tres meses. Conclusión: Los niños evaluados tienen un bajo consumo de nutrientes, entre ellos el calcio, deficiente administración de vitamina D en el primer semestre de vida, poco actividad física regular y la alta prevalencia del sobrepeso y la obesidad son factores que pueden afectar a la formación de masa ósea.

  8. [Adherence to a mediterranean diet and sport performance in a elite female athletes futsal population].

    PubMed

    Rubio-Arias, Jacobo Ángel; Ramos Campo, Domingo Jesús; Ruiloba Nuñez, Juana María; Carrasco Poyatos, María; Alcaraz Ramón, Pedro Emilio; Jiménez Díaz, Fernando José

    2015-05-01

    Introducción: Baja ingesta de energía puede dar lugar a la pérdida de masa muscular, disfunciones menstruales, un aumento del riesgo de la fatiga, lesión así como la necesidad de un proceso prolongado de recuperación. Objetivos: 1) Analizar el nivel de adherencia al Patrón de Dieta Mediterráneo en un grupo de mujeres deportistas profesionales de fútbol sala, 2) analizar el grado de relación entre el Patrón Dietético Mediterráneo, la composición corporal y el rendimiento deportivo y, 3) analizar si el actual grado de adherencia a la dieta mediterránea establece diferencias en los test de rendimiento deportivo y sobre la composición corporal. Métodos: Se valoró el PDM, test de composición corporal, test isocinético, test salto vertical (CMJ y SJ), golpeo de balón, test de velocidad y test Repeated Sprint Ability (RSA). Resultados: se observó que 7 de los 12 jugadoras (58,33%) mostró un patrón bajo y 5 de las 12 jugadoras (41,67%) un patrón medio. Por otro lado, estos patrones de adherencia no correlacionoraon con los valores de composición corporal ni con los test de rendimiento deportivo. No se observaron diferencias significativas entre las jugadoras que tenían un grado medio de adherencia con las que tenían un patrón bajo de adhesión. Sin embargo, la cantidad de grasa total (%) parece tener un efecto determinante en la capacidad de repetir sprint. Conclusión: Se observan bajos niveles de adhesión a la dieta mediterránea, los valores mostrados en el cuestionario KIDMED no se han relacionado con el rendimiento de las deportistas ni con el estado de la composición corporal.

  9. [Not Available].

    PubMed

    Rojo-Trejo, María Elena; Rangel Peniche, Diana Beatriz; Arellano Jiménez, María Del Rocío; Sabath Silva, Ernesto Francisco

    2016-06-30

    Introducción: el bajo peso al nacer (BPN) es un factor de riesgo para desarrollar obesidad en la vida adulta.Objetivo: evaluar diferencias en la composición corporal de niños de entre 8 y 10 años de edad con y sin antecedente de BPN.Métodos: fue un estudio observacional, transversal comparativo. Participaron 112 niños (95 con adecuado peso al nacer [APN] y 17 con BPN). Se realizó antropometría (peso, talla, circunferencias de cintura y cadera, pliegue cutáneo de tríceps [PCT] y subescapular [PCSE]).Resultados: se encontró una prevalencia combinada del 41% para sobrepeso y obesidad en ambos grupos de estudio. El porcentaje de grasa corporal total fue menor en las niñas con BPN (no significativo); sin embargo, el indicador PCT-PCSE fue significativamente más alto (p = 0,04) que el de las niñas con APN. En contra de lo esperado, al estratificar según porcentaje de grasa y peso al nacer, se encontró que el grupo con BPN presentó un porcentaje de grasa bajo (p < 0,05) en comparación con el grupo de APN, siendo 6 veces mayor la posibilidad de que un niño con BPN presente porcentaje de grasa total bajo a esta edad.Conclusiones: a estas edades no se encontró mayor porcentaje de grasa en el grupo con BPN en comparación con el de APN; sin embargo, las niñas con BPN presentaron mayor deposición de grasa troncal que las de APN. La deposición de grasa es un indicador que hay que considerar, y no únicamente el índice de masa corporal, en la evaluación nutricia infantil.

  10. Improved metabolic response after 16 weeks of calorie-restricted low-glycaemic index diet and metformin in impaired glucose tolerance subjects.

    PubMed

    Macedo da Costa, Teresa Helena; Pires da Silva, Fábio Vinícius; Gonçalves Reis, Caio Eduardo; Augusto Casulari, Luiz

    2014-05-01

    Objetivo: Este estudio analizaba los efectos metabólicos del consejo dietético de seguir una dieta con restricción calórica y un índice glucémico bajo junto con Metformina en individuos con sobrepeso / obesidad y tolerancia alterada a la glucosa. Métodos: Se siguió mensualmente durante 16 semanas a 16 individuos con un índice de masa corporal entre 27-38 kg/m² y se les trató con Metformina (1 g/día) y una prescripción dietética con un índice glucémico bajo y una reducción del energía del 25-30 ¡% de su gasto energético total. Se midieron el metabolismo de la glucosa, el perfil lipídico, la composición antropométrica y corporal y los parámetros de consumo de alimentos antes y después del tratamiento. Se emplearon las pruebas t pareadas y de Wilcoxon para comparar las diferencias con respecto al basal, con un criterio de significación estadística de p ≤0,05. Resultados: Hubo reducciones significativas en los parámetros de composición corporal y antropométricos, una disminución en las concentraciones de HOMA2-% y e triglicéridos y un aumento del índice de Cederholm. Estos resultados muestran una mejora de la sensibilidad periférica a la insulina y una conservación de la función de las células beta pancreáticas. Conclusión: la dieta con restricción calórica y un índice glucémico bajo junto con Metformina fueron beneficiosas para los parámetros metabólicos y antropométricos en individuos con sobrepeso/obesidad y una tolerancia a la glucosa alterada.

  11. Discriminatory power of indicators predictors of visceral adiposity evaluated by computed tomography in adults and elderly individuals.

    PubMed

    Carneiro Roriz, Anna Karla; Santana Passos, Luiz Carlos; Cunha de Oliveira, Carolina; Eickemberg, Michaela; de Almeida Moreira, Pricilla; Ramos Sampaio, Lílian

    2014-06-01

    Introducción: La identificación de métodos antropométricos de adiposidad abdominal, los predictores de exceso del tejido adiposo visceral (TAV) permiten una evaluación rápida y de bajo costo del riesgo de enfermedades cardiovasculares en ancianos. Objetivo: Evaluar el poder discriminatorio de los indicadores antropométricos para la detección de exceso del tejido adiposo visceral. Métodos: Estudio transversal compuesto por 194 adultos y ancianos para la comparación entre ambos sexos y por grupos de edad. Las variables antropométricas: Razón cintura/estatura (RCE), Razón cintura/muslo (RCM), el Índice Diámetro Abdominal (SAD/muslo) e el Índice diámetro abdominal altura (SAD/estatura). El área TAV fue identificado por tomografía computarizada. Análisis con la curva ROC. Resultados: Se observó una alta correlación entre el área del tejido adiposo visceral y la mayoría de los indicadores antropométricos (p ≤0,001). Entre los hombres de edad avanzada, la razón cintura/estatura mostró áreas bajo la curva ROC por encima de 0,90 y puntos de corte de 0,55 (sens: 85,7%, espec: 82,4%, VPP: 99,9%). Para las mujeres de edad avanzada, el corte fue de 0,58 (sens: 81,0%, espec: 78,6%). Para SAD/estatura, las áreas bajo la curva ROC fueron ≥0,83 (p ≤0,01), con puntos de corte de 0,12 para hombres y 0,13 para las mujeres. Conclusión: Había se ha observado un fuerte poder discriminatorio de los indicadores antropométricos de obesidad abdominal visceral. La Razón cintura/altura y el diámetro abdominal estatura mostraron un mejor desempeño para predecir la área de TAV de riesgo en los ancianos, sin la necesidad de medirla por tomografía computarizada.

  12. [Not Available].

    PubMed

    Rojo-Trejo, María Elena; Rangel Peniche, Diana Beatriz; Arellano Jiménez, María Del Rocío; Sabath Silva, Ernesto Francisco

    2016-01-01

    Introducción: el bajo peso al nacer (BPN) es un factor de riesgo para desarrollar obesidad en la vida adulta.Objetivo: evaluar diferencias en la composición corporal de niños de entre 8 y 10 años de edad con y sin antecedente de BPN.Métodos: fue un estudio observacional, transversal comparativo. Participaron 112 niños (95 con adecuado peso al nacer [APN] y 17 con BPN). Se realizó antropometría (peso, talla, circunferencias de cintura y cadera, pliegue cutáneo de tríceps [PCT] y subescapular [PCSE]).Resultados: se encontró una prevalencia combinada del 41% para sobrepeso y obesidad en ambos grupos de estudio. El porcentaje de grasa corporal total fue menor en las niñas con BPN (no significativo); sin embargo, el indicador PCT-PCSE fue significativamente más alto (p = 0,04) que el de las niñas con APN. En contra de lo esperado, al estratificar según porcentaje de grasa y peso al nacer, se encontró que el grupo con BPN presentó un porcentaje de grasa bajo (p < 0,05) en comparación con el grupo de APN, siendo 6 veces mayor la posibilidad de que un niño con BPN presente porcentaje de grasa total bajo a esta edad.Conclusiones: a estas edades no se encontró mayor porcentaje de grasa en el grupo con BPN en comparación con el de APN; sin embargo, las niñas con BPN presentaron mayor deposición de grasa troncal que las de APN. La deposición de grasa es un indicador que hay que considerar, y no únicamente el índice de masa corporal, en la evaluación nutricia infantil. PMID:27513486

  13. [Food insecurity among elderly people in 15 districts of the Great Santiago area; an unresolved issue].

    PubMed

    Vargas Puello, Vianny; Alvarado Orellana, Sergio; Atalah Samur, Eduardo

    2013-01-01

    Introducción: Experimentar inseguridad alimentaria determina consecuencias negativas en la nutrición, salud y bienestar general de los adultos mayores y sus familias. En Chile prácticamente no existe información al respecto, a pesar de ser un importante problema de salud pública en otros países de la región. Objetivos: Determinar la prevalencia de inseguridad alimentaria y su relación con factores sociodemográficos, económicos y nutricionales en Adultos Mayores residentes en comunas del nivel socioeconómico medio-bajo y bajo del Gran Santiago. Materiales y métodos: Estudio observacional transversal en 344 adultos mayores de 65 a 74 años; encuesta socioeconómica, demográfica, nutricional y de inseguridad alimentaria en el hogar (HFIAS). Se determinó prevalencia de inseguridad alimentaria y su relación con las variables independientes por modelos de regresión logística multivariados. Resultados: El 40,4% de muestra presentaba inseguridad alimentaria (95% IC 35,2-45,6%), predominantemente de tipo leve, con una proporción mayor en mujeres, en el límite de la significación estadística. La probabilidad de percibir inseguridad alimentaria se asoció significativamente con bajos ingresos familiares (OR 4,2 IC 2,1-8,6), con mayor número de personas en el hogar (OR 2,4), malnutrición por déficit o exceso (OR 2,0), no ser propietario de la vivienda (OR 2,0) y menores ingresos personales (OR 1,8). Conclusiones: Existe una alta prevalencia de inseguridad alimentaria en esta población, la que se asocia con variables sociodemográficas, económicas y nutricionales. La seguridad alimentaria es un importante tema de salud pública y nutrición en el país, que debe ser investigado en mayor profundidad.

  14. Adapting a Common Photographic Camera to Take Pictures of the Sky. (Spanish Title: Adaptando Una Camara Fotografica Comun Para Obtener Fotografias del Cielo.) Adaptando Uma Câmera Fotográfica Manual Simples Para Fotografar o Céu

    NASA Astrophysics Data System (ADS)

    Danhoni Neves, Marcos Cesar; Pereira, Ricardo Francisco

    2007-12-01

    In this paper will be introduced a method of astrophotography using a non-reflex photographic camera (a low-cost method). It will be revised some photographic processes commonly used nowadays for comparison with the aims of this paper. En este trabajo será introducido un método de astrofotografia que utiliza una cámara fotográfica non-reflex (un método de bajo costo). Serán revisados algunos procesos fotográficos comúnmente utilizados actualmente para comparación con los objetivos de este trabajo. O presente artigo procura introduzir um método de astrofotografia utilizando uma câmera fotográfica não reflex, de baixo custo. É feita uma revisão do processo fotográfico comumente empregado para fins de comparação com os objetivos pretendidos no presente trabalho.

  15. [Not Available].

    PubMed

    Ortega Anta, Rosa M

    2016-01-01

    En el presente suplemento de la revista Nutrición Hospitalaria se resumen las conferencias presentadas en las Terceras Jornadas UCMASEN (Universidad Complutense de Madrid - Asociación de Estudios Nutricionales), bajo el título "Nutrición como estrategia en la mejora y promoción de la salud", que se celebraron durante los días 3 y 4 de febrero de 2016 en la Facultad de Farmacia de la Universidad Complutense de Madrid. Estas Jornadas han sido una actividad promovida por el grupo de investigación UCM-VALORNUT y han contado con el apoyo institucional de la Fundación Española de la Nutrición (FEN). PMID:27571854

  16. H3+: superficies de energía potencial, estados y transiciones rovibracionales

    NASA Astrophysics Data System (ADS)

    Aguado, M. Paniagua Y. A.

    Hemos calculado varias superficies globales de energía potencial para el estado fundamental y excitados del sistema H3+ en más de ocho mil geometrías diferentes usando una base (9s 3p 1d)/[4s 3p 1d] en cada átomo de Hidrógeno y mediante un método de cálculo de interacción de configuraciones completa (FCI). Hemos ajustado las superficies a formas analíticas del tipo Aguado y Paniagua con un error promedio menor de 50 cm-1 y menor en el pozo de potencial del estado fundamental. Finalmente hemos calculado y analizado los niveles vibracionales para los dos estados electrónicos más bajos, siendo la desviación respecto de los mejores valores publicados, tanto experimentales como teóricos, de unos pocos números de onda.

  17. Description of a sauropod dinosaur braincase from the Late Cretaceous Rio Colorado Subgroup, Patagonia.

    PubMed

    Calvo, Jorge O; Kellner, Alexander W

    2006-03-01

    The fossil record of cranial material from titanosaurid sauropods is very poor and no complete skull has been described so far. Here we describe a new braincase (MUCPv-334) that was recovered from reddish sandstones of the Rio Colorado Subgroup (Late Cretaceous) of the region of Bajo del Añelo, approximately 20 km north of the town Añelo (Neuquén Province, Argentina). This specimen is attributed to the Titanosauridae based on the ventrally projected basipterygoid processes, a common condition shared by other titanosaurids. The robustness of MUCPv-334 together with an unusually expanded crista prootica and the presence of an anterior prolongation of the parasphenoid reaching the basal tubera were not reported in other members of the Titanosauridae, indicating a larger diversity in the braincase morphology of this sauropod clade than previously thought.

  18. Preliminary observations on Quaternary reverse faulting along the southern front of the Northern Range of Trinidad

    SciTech Connect

    Beltran, C. , Caracus )

    1993-02-01

    Several geomorphological evidences of Quaternary reverse faulting are observed along the southern front of the Northern Range in Trinidad between Port-of-Spain and Matura Point. Such a mountain front is associated to a reverse fault system showing an imbricated pattern southward. In the north, the system is limited by a structural feature showing an important vertical component. Southward this system progressively changes to low angle faults. This geometry is corroborated by seismic profiling in the continent shelf. The active faulting evidences consist in lateral drainage offsets, fault trenches, sag-ponds, triangular facets, and saddles. Some quaternary terraces show fault scarps and tilting. We postulate that these reverse fault systems as Arima Fault instead of El Pilar fault as it is not actually connected to the San Sebestian-El Pilar right-lateral slip system, due to the southward prolongation of the southern limit of the Caribbean Plate through the fault system of Los Bajos-El Soldado.

  19. "A century of civilization under the influence of eugenics": Dr. Enrique Diego Madrazo, socialism and scientific progress.

    PubMed

    Cleminson, Richard

    2006-01-01

    This article discusses the thought of one of the pioneers of eugenics in Spain, Dr. Enrique Diego Madrazo. In particular, it analyses his 1930 essay Un siglo de civilización bajo la influencia eugenésica [A Century of Civilization under the Influence of Eugenics], as the most explicit work on the eugenic utopia he advocated. This work, because of its breadth, was also one of the most extensive and detailed accounts of the steps to be taken towards the eugenic society that was produced. The present analysis of his work assesses the degree to which his thought, which has been described as "utopian socialist", in fact corresponded to that epithet, given the politically authoritarian nature and the gender bias of some aspects of his one-hundred year plan for the creation of a eugenic society. The article also places Madrazo's thought in the context of his time and other national currents of eugenic thought.

  20. Como Lo Hago Yo: Myelomeningocele

    PubMed Central

    Lazareff, Jorge

    2014-01-01

    Fortificación con ádico fólico es efectiva, pero aún falta conciencia en los jóvenes. La legalidad del aborto aumenta la importancia de la consulta prenatal. Realizo la cirugía bajo microcoscopio por razones didácticas. Irrigación continua para reducir la temperatura del tejido. Trato a la plaqueta como tejido viable. No suturo la plaqueta. No cierro músculo. ATB por una semana después de cirugía. Hidrocefalia: Válvula en todos los casos de ventriculomegalia. Médula anclada: Desanclar una sola vez. Chiari II: Revisar la válvula. Incluir en el seguimiento rendimiento escolar, puede indicar obstrucción de la válvula o médula anclada. PMID:24791217

  1. [Oropharyngeal dysphagia associated with Chiari I malformation and syringomyelia J].

    PubMed

    Cortés-Medina, Julio César; Cárdenas-Lara, Armando; Guerrero-Rascón, Carlos Alberto; Rodríguez-Bautista, Heber

    2014-01-01

    Antecedentes: la disfagia con afección neurológica constituye un dato clínico significativo en el diagnóstico de lesiones que justifiquen la compresión del tronco cerebral y los nervios craneales bajos. Objetivo: destacar la importancia del estudio de la disfagia en una paciente con malformación de Chiari tipo I y siringomielia, sin síntomas gastroenterológicos primarios. Caso clínico: se comunica el caso de una mujer de 62 años de edad con disfagia orofaríngea de seis años de evolución, cervicobraquialgia, ptosis palpebral y diplejía facial. Conclusiones: el estudio por resonancia magnética constituye un elemento fundamental para establecer el diagnóstico causal de la disfagia neurogénica.

  2. [Not Available].

    PubMed

    Ortega Anta, Rosa M

    2016-07-12

    En el presente suplemento de la revista Nutrición Hospitalaria se resumen las conferencias presentadas en las Terceras Jornadas UCMASEN (Universidad Complutense de Madrid - Asociación de Estudios Nutricionales), bajo el título "Nutrición como estrategia en la mejora y promoción de la salud", que se celebraron durante los días 3 y 4 de febrero de 2016 en la Facultad de Farmacia de la Universidad Complutense de Madrid. Estas Jornadas han sido una actividad promovida por el grupo de investigación UCM-VALORNUT y han contado con el apoyo institucional de la Fundación Española de la Nutrición (FEN).

  3. [In Process Citation].

    PubMed

    Muros, José Joaquín; Briones, Mercedes; Rodríguez, Guillermo; Bouzas, Paula R; Giménez, Rafael; Cabrera-Vique, Carmen

    2016-03-25

    Introducción: Guatemala ha estado experimentando una transición en sus estilos de vida. Mientras que la desnutrición crónica sigue siendo prevalente, se ha experimentado un aumento sustancial de los casos de obesidad. Objetivo: proporcionar información actualizada sobre las nuevas tendencias en cuanto al estado nutricional en Guatemala. Métodos: se diseñó un estudio transversal con una muestra de 392 niños y adolescentes (5-18 años) seleccionados de manera aleatoria. El muestreo fue estratificado según su ubicación geográfica (rural y urbana), sexo y edad. Resultados: alrededor del 62% de la muestra urbana presentó problemas de sobrepeso y un 13,8 de obesidad. Entre los participantes urbanos, la prevalencia de sobrepeso/obesidad fue mayor en el grupo de 11-14 años. El grupo urbano presentó una mayor prevalencia de sobrepeso/obesidad que el grupo rural para todos los grupos de edad (excepto en el grupo de 15-18 años que presentó unos índices de obesidad ligeramente más elevados en el grupo rural). Se observó una mayor prevalencia de retraso en el crecimiento en el grupo rural, excepto para el grupo de edad de 15-18 años. La prevalencia de bajo peso fue significativamente mayor en el grupo rural (25% vs. 1,2%) así como la prevalencia del delgadez, excepto para el grupo de edad de 5-10 años. Conclusión: la alta prevalencia de bajo peso y la de sobrepeso/obesidad coexisten en los niños y adolescentes en Guatemala.

  4. [RELATIONSHIP BETWEEN BODY MASS INDEX, PHYSICAL ACTIVITY AND MEAL TIMES IN MEXICAN ADOLESCENTS].

    PubMed

    Saucedo-Molina, Teresita de Jesùs; Rodríguez Jiménez, Juana; Oliva Macías, Luz Alejandra; Villarreal Castillo, Martín; León Hernández, Rodrigo César; Fernández Cortés, Trinidad Lorena

    2015-09-01

    Objetivos: los objetivos de este estudio son: 1) describir la distribución del IMC, los niveles de actividad física y la frecuencia de los tiempos de comida, y 2) examinar la relación de estas variables con el IMC en una muestra de adolescentes mexicanos estudiantes de preparatoria. Métodos: participaron 1.028 adolescentes (58,9% mujeres y 41,1% hombres) de 15 a 19 años de edad (M= 16,12; DE= 0,9). Se calculó el IMC y se utilizó la referencia del CDC-2000. Los tiempos de comida se midieron con uno de los factores del cuestionario Factores de Riesgo Asociados a Trastornos Alimentarios para Púberes (FRATAP). La actividad física se evaluó mediante el International Physical Activity Questionnaire (IPAQ) en su versión corta. Se realizaron correlaciones de Pearson para ver la relación entre las variables. Resultados: la prevalencia combinada de sobrepeso y obesidad alcanzó el 29,2% para mujeres y el 29,3% en hombres. En el factor tiempos de comida, los sujetos con desnutrición y bajo peso fueron quienes siempre obtuvieron los valores más altos en la opción de respuesta. El 31,9% del total de la muestra reportó un nivel de actividad física bajo. Los tiempos de comida mostraron asociaciones significativas con el IMC (r= -0,142, p < 0,01) y los niveles de actividad física (r= 0,125, p < 0,01). Discusión: en la muestra se identificaron problemas importantes de malnutrición, frecuencia de comidas e inactividad física. De estos hallazgos surge la necesidad de diseñar e implantar programas para promover estilos de vida saludables en adolescentes.

  5. [In Process Citation].

    PubMed

    Álvarez, Cristian; Ramírez-Campillo, Rodrigo; Vallejos-Rojas, Andrea; Jaramillo-Gallardo, Javiera; Salas Bravo, Carlos; Cano-Montoya, Johnattan; Celis-Morales, Carlos

    2016-03-25

     Introducción: obesidad e inactividad física son importantes factores de riesgo para el desarrollo de hipertensión en adultos. No obstante, hay poca evidencia sobre el efecto de estos factores de riesgo en el desarrollo de hipertensión en población infantil. Objetivo: investigar la asociación del estado nutricional, niveles de actividad física y etnicidad con niveles de hipertensión en escolares entre 6 y 13 años de edad. Métodos: un total de 418 escolares de ascendencia étnica europea (n = 311) y mapuche (n = 107) fueron participantes de este estudio transversal. Se midió el peso, talla, índice de masa corporal (IMC) y presión arterial, utilizando protocolos estandarizados. Resultados: no se encontraron diferencias significativas en IMC, estado nutricional y presión arterial entre niños con ascendencia europea y mapuche. No obstante, la prevalencia de prehipertensión (21,3% vs. 11,1%) e hipertensión (28,9% vs. 18,6%) fue significativamente mayor en escolares mapuches en comparación con europeos, respectivamente. Escolares con ascendencia mapuche tienen un mayor riesgo de desarrollar prehipertensión o hipertensión que escolares con ascendencia europea (OR: 1,92 [1,19 a 3,06], p < 0,01). La prevalencia de hipertensión aumenta significativamente en ambos grupos étnicos con el incremento de IMC y bajos niveles de actividad física. Conclusiones: el riesgo de desarrollar prehipertensión o hipertensión es mayor en población infantil ascendiente de mapuches que ascendiente de europeos y este riesgo se ve acentuado con el incremento de obesidad y bajos niveles de actividad física.

  6. [Not Available].

    PubMed

    Flores Navarro-Pérez, Carmen; González-Jiménez, Emilio; Schmidt-RioVilla, Jacqueline; Meneses-Echávez, José Francisco; Correa-Bautista, Jorge Enrique; Correa-Rodríguez, María; Ramírez-Vélez, Robinson

    2016-01-01

    Objetivos: los objetivos de este estudio fueron analizar el nivel nutricional en una población de niños y adolescentes colombianos y determinar la posible relación entre el nivel nutricional y el estado nutricional según el índice de masa corporal (IMC) y la circunferencia de cintura (CC).Material y métodos: estudio transversal en 6.383 niños y adolescentes de entre 9 y 17,9 años de edad, de Bogotá, Colombia. Se aplicó de manera autodiligenciada el cuestionario Krece Plus validado en el estudio enKid como indicador del nivel nutricional con las categorías alto (test ≥ 9), medio (test 6-8) y bajo (test ≤ 5). Se tomaron medidas de peso, talla, CC, y se calculó el IMC como marcadores del estado nutricional.Resultados: de la población general, el 57,9% eran chicas (promedio de edad 12,7 ± 2,3 años). En todas las categorías del IMC, más del 50% de chicos y chicas siguen una dieta de muy baja calidad, que empeora progresivamente con el avance en edad. En ambos sexos, se observaron tendencias entre un nivel nutricional muy bajo con el desarrollo de sobrepeso. Asimismo, la obesidad abdominal por CC se relacionó con una puntuación baja en el Krece Plus en ambos sexos.Conclusiones: en escolares de Bogotá, una dieta de muy baja calidad se relacionó con alteraciones del estado nutricional (IMC y CC), especialmente entre chicas y adolescentes. Estos resultados deben alentar el desarrollo de intervenciones orientadas a mejorar los hábitos nutricionales entre los escolares colombianos. PMID:27571667

  7. [NORMATIVE VALUES OF SF-6D QUESTIONNAIRE FOR CHILEAN DIABETES PATIENTS].

    PubMed

    Garcia-Gordillo, Miguel A; Collado-Mateo, Daniel; Olivares, Pedro R; Adsuar, José C

    2015-12-01

    Introducción: la diabetes mellitus es una de las enfermedades crónicas de mayor prevalencia e impacto económico a nivel mundial. La diabetes produce un impacto sobre la calidad de vida relacionada con la salud de las personas que la padecen. El cuestionario SF-6D permite evaluar la calidad de vida relacionada con la salud. Es uno de los cuestionarios más usados a nivel mundial, ya que permite conocer las preferencias sociales de los distintos estados de salud. Sin embargo, según nuestro conocimiento no se dispone de los valores normativos de este cuestionario en la población diabética chilena. Objetivo: reportar los datos normativos del cuestionario SF-6D en la población diabética chilena. Métodos: los datos fueron extraídos de la Encuesta Nacional de Salud (ENS 2009-2010) de Chile. En este estudio se incluyen 424 personas que presentan diabetes (143 hombres y 281 mujeres). Los datos se han presentado segregados por sexo y grupo de edad, así como por región, estado civil, hábito tabáquico, nivel de ingresos y estudios. Resultados: el índice de utilidad del SF-6D en mujeres chilenas con diabetes fue de 0,65 (± 0,15), mientras que en hombres fue 0,70 (± 0,15). Menos del 5% de la población declara una utilidad con valor 1. El índice de utilidad del SF-6D en pacientes con diabetes disminuye con la edad, en las situaciones de bajos ingresos y con niveles de educación bajos. Conclusiones: este estudio presenta los valores normativos chilenos del SF-6D derivado del SF-12 en pacientes con diabetes.

  8. [Food consumption in and around the school].

    PubMed

    Alvear-Galindo, M Guadalupe; Yamamoto-Kimura, Liria T; Morán-Álvarez, Cristina; Solís-Días, M Guadalupe; Torres-Durán, Patricia Victoria; Juárez-Oropeza, Marco Antonio; Acuña-Sánchez, M Eugenia; Ferreira-Hermosillo, Aldo

    2013-01-01

    Introducción: en México, los niños de primaria permanecen aproximadamente 4.5 horas en la escuela, por lo que fuera de ese espacio es donde consumen la mayor parte de sus alimentos. El objetivo de esta investigación fue explorar las conductas alimentarias más allá del entorno escolar que pudieran favorecer la obesidad. Métodos: estudio descriptivo de niños de una escuela primaria oficial en el Distrito Federal. Los hábitos alimentarios se conocieron por un cuestionario y las características antropométricas, por medición física. Resultados: los participantes indicaron consumir refrescos y jugos enlatados con alta frecuencia y en cantidades importantes (80 %), así como productos lácteos industrializados con alto valor calórico y bajo contenido de proteínas; ingerían pocos alimentos de origen animal; 30 % comía cuatro o cinco veces al día y 10 %, una o dos veces. Los resultados se asociaron con las características omatométricas de los niños, 37.6 % de los cuales presentó sobrepeso u obesidad y 12 %, bajo peso. Conclusiones: para la prevención de la obesidad son necesarios programas de educación que involucren a profesores, padres de familia y escolares, para obtener conductas saludables y preservar la salud.

  9. [Imposex in Voluta musica (Caenogastropoda: Volutidae) from Northeastern Peninsula de Araya, Venezuela].

    PubMed

    Peralta, Ana Carolina; Miloslavich, Patricia; Bigatti, Gregorio

    2014-06-01

    Voluta musica is a dioecious marine gastropod endemic of the South Caribbean. Tributyltin (TBT) and copper (Cu) are potential inducers of imposex, an endocrine disorder by which females develop a penis and/or vas deferens. The goal of this work was to determine the imposex incidence in V. musica populations from Northeastern Peninsula de Araya. For this, we selected three sites (Isla Caribe, Isla Lobos and Bajo Cuspe) and made monthly samplings of 15 snails in each site, during one year, and determined: (1) sizes; (2) sex and imposex incidence and (3) the Relative Penis Length Index (RPLI). We also performed histological analysis of the gonads, and measured TBT and Cu concentrations in sediments from the studied localities. Our results showed that the total number of sampled females affected by imposex was 24.5% at Isla Caribe, 12% at Isla Lobos, and none at Bajo Cuspe. In sediments, Cu was detected mostly in Isla Lobos. The female gonads with imposex did not show any development of male cells in any of the sampled sites. The higher percentage of females with imposex matched with the higher boat traffic locality, and higher TBT level (Isla Caribe). No esterilization was evident in this work, nevertheless, the presence of TBT and Cu in the sediments and females with imposex were considered as a potential threat to V. musica populations in this region. In Venezuela there is no control over this particular issue, possibly because of the lack of information and research in this topic, but certainly, this information will be useful in biodiversity conservation policies.

  10. [Influence of sport practice and physical exercise on anthropometric indicators and weight satisfaction in men university students: a pilot study].

    PubMed

    Telleria-Aramburu, Nerea; Sánchez, Celia; Ansotegui, Laura; Rocandio, Ana M; Arroyo-Izaga, Marta

    2014-10-03

    Introducción: Los jovenes universitarios presentan en general niveles bajos de actividad fisica, lo que podria repercutir en su peso y composicion corporal y en el conocimiento y aceptacion de su propio cuerpo. Objetivo: Evaluar el estado de peso y la composicion corporal, asi como la autopercepcion y satisfaccion con el peso corporal en universitarios, y analizar la influencia de la actividad fisico-deportiva sobre estas variables. Métodos: La muestra estuvo formada por 62 estudiantes varones con una edad media de 20,7+/-1,7 anos. La practica de deporte y/o ejercicio fisico en el tiempo libre se analizo mediante cuestionario. El estado de peso y la composicion corporal se evaluaron mediante antropometria. Tambien se registraron datos de peso autodeclarado y deseado, y de talla autodeclarada. Las medidas de peso real, autodeclarado y deseado se utilizaron para estimar la autopercepcion y satisfaccion con el peso. El analisis estadistico se realizo con el programa SPSS version 22.0. Resultados: El 17,7% de los participantes presentaba sobrepeso y el 6,5% bajo peso. El 45,2% tenia un gasto por el deporte y/o ejercicio fisico ≤ 3.000 kcal/semana y el 32,3% > 3.000 kcal/semana. La autopercepcion y satisfaccion con el peso fue mejor en el grupo que practicaba deporte y/o ejercicio fisico a razon de ≤ 3.000 kcal/semana, que en aquellos que no practicaban ningun ejercicio fisico o deporte (P < 0,05). Conclusión: La practica regular de actividad fisicodeportiva moderada esta relacionada con una mejor percepcion y satisfaccion con el peso corporal, en comparacion con el sedentarismo. Deberia aprovecharse el periodo de estudios universitarios para fomentar la practica de ejercicio fisico-deportivo, empleando los recursos o activos con los que cuenta la Universidad.

  11. [In Process Citation].

    PubMed

    Álvarez, Cristian; Ramírez-Campillo, Rodrigo; Vallejos-Rojas, Andrea; Jaramillo-Gallardo, Javiera; Salas Bravo, Carlos; Cano-Montoya, Johnattan; Celis-Morales, Carlos

    2016-01-01

     Introducción: obesidad e inactividad física son importantes factores de riesgo para el desarrollo de hipertensión en adultos. No obstante, hay poca evidencia sobre el efecto de estos factores de riesgo en el desarrollo de hipertensión en población infantil. Objetivo: investigar la asociación del estado nutricional, niveles de actividad física y etnicidad con niveles de hipertensión en escolares entre 6 y 13 años de edad. Métodos: un total de 418 escolares de ascendencia étnica europea (n = 311) y mapuche (n = 107) fueron participantes de este estudio transversal. Se midió el peso, talla, índice de masa corporal (IMC) y presión arterial, utilizando protocolos estandarizados. Resultados: no se encontraron diferencias significativas en IMC, estado nutricional y presión arterial entre niños con ascendencia europea y mapuche. No obstante, la prevalencia de prehipertensión (21,3% vs. 11,1%) e hipertensión (28,9% vs. 18,6%) fue significativamente mayor en escolares mapuches en comparación con europeos, respectivamente. Escolares con ascendencia mapuche tienen un mayor riesgo de desarrollar prehipertensión o hipertensión que escolares con ascendencia europea (OR: 1,92 [1,19 a 3,06], p < 0,01). La prevalencia de hipertensión aumenta significativamente en ambos grupos étnicos con el incremento de IMC y bajos niveles de actividad física. Conclusiones: el riesgo de desarrollar prehipertensión o hipertensión es mayor en población infantil ascendiente de mapuches que ascendiente de europeos y este riesgo se ve acentuado con el incremento de obesidad y bajos niveles de actividad física. PMID:27238776

  12. [Not Available].

    PubMed

    Flores Navarro-Pérez, Carmen; González-Jiménez, Emilio; Schmidt-RioVilla, Jacqueline; Meneses-Echávez, José Francisco; Correa-Bautista, Jorge Enrique; Correa-Rodríguez, María; Ramírez-Vélez, Robinson

    2016-07-19

    Objetivos: los objetivos de este estudio fueron analizar el nivel nutricional en una población de niños y adolescentes colombianos y determinar la posible relación entre el nivel nutricional y el estado nutricional según el índice de masa corporal (IMC) y la circunferencia de cintura (CC).Material y métodos: estudio transversal en 6.383 niños y adolescentes de entre 9 y 17,9 años de edad, de Bogotá, Colombia. Se aplicó de manera autodiligenciada el cuestionario Krece Plus validado en el estudio enKid como indicador del nivel nutricional con las categorías alto (test ≥ 9), medio (test 6-8) y bajo (test ≤ 5). Se tomaron medidas de peso, talla, CC, y se calculó el IMC como marcadores del estado nutricional.Resultados: de la población general, el 57,9% eran chicas (promedio de edad 12,7 ± 2,3 años). En todas las categorías del IMC, más del 50% de chicos y chicas siguen una dieta de muy baja calidad, que empeora progresivamente con el avance en edad. En ambos sexos, se observaron tendencias entre un nivel nutricional muy bajo con el desarrollo de sobrepeso. Asimismo, la obesidad abdominal por CC se relacionó con una puntuación baja en el Krece Plus en ambos sexos.Conclusiones: en escolares de Bogotá, una dieta de muy baja calidad se relacionó con alteraciones del estado nutricional (IMC y CC), especialmente entre chicas y adolescentes. Estos resultados deben alentar el desarrollo de intervenciones orientadas a mejorar los hábitos nutricionales entre los escolares colombianos.

  13. [Environmental UV radiation levels for dosing PUVA-sol in Mexico].

    PubMed

    Castanedo-Cázares, Juan Pablo; Torres-Álvarez, Bertha; Ehnis-Pérez, Adriana; Alba-Barba, Isaura

    2013-01-01

    Introducción: la terapia PUVA-sol tiene como ventaja su disponibilidad y bajo costo. Sin embargo, su utilización es empírica. La finalidad del estudio es cuantificar la radiación solar UVA ambiental y sugerir una forma de administración en México. Métodos: se midió la radiación UV en el centro del país (22 °N, 101 °O, 1877 m) mediante radiometría terrestre de 2007 a 2011. Se registró la variación por hora, mes, nubosidad y transmisión a través de placas de silicato doméstico. Resultados: más del 75 % de la radiación UVA se registra entre las 9:00 y las 17:00 horas. La intensidad anual promedio mínima fue de 20 mW/cm(2) y la máxima de 25.4 mW/cm(2) (ANOVA, p < 0.001). El cálculo de irradiación UVA mensual durante el cenit bajo cielo despejado puede estimarse mediante la fórmula: 23.8 + 0.13 (mes) - 0.13 (mes - 6.5)(2), (r(2) = 0.95, p < 0.001). La placa común (3 mm) de silicato doméstico tiene una absorbancia UVB de 0.93 y una transmitancia UVA de 0.58. Conclusiones: es posible el empleo racional de PUVA-sol según los datos obtenidos. Es necesario aislar la radiación UVB y ajustar la dosis según la nubosidad, así como apegarse al protocolo de seguridad a fin de obtener beneficios y minimizar los efectos adversos.

  14. [In Process Citation].

    PubMed

    Muros, José Joaquín; Briones, Mercedes; Rodríguez, Guillermo; Bouzas, Paula R; Giménez, Rafael; Cabrera-Vique, Carmen

    2016-01-01

    Introducción: Guatemala ha estado experimentando una transición en sus estilos de vida. Mientras que la desnutrición crónica sigue siendo prevalente, se ha experimentado un aumento sustancial de los casos de obesidad. Objetivo: proporcionar información actualizada sobre las nuevas tendencias en cuanto al estado nutricional en Guatemala. Métodos: se diseñó un estudio transversal con una muestra de 392 niños y adolescentes (5-18 años) seleccionados de manera aleatoria. El muestreo fue estratificado según su ubicación geográfica (rural y urbana), sexo y edad. Resultados: alrededor del 62% de la muestra urbana presentó problemas de sobrepeso y un 13,8 de obesidad. Entre los participantes urbanos, la prevalencia de sobrepeso/obesidad fue mayor en el grupo de 11-14 años. El grupo urbano presentó una mayor prevalencia de sobrepeso/obesidad que el grupo rural para todos los grupos de edad (excepto en el grupo de 15-18 años que presentó unos índices de obesidad ligeramente más elevados en el grupo rural). Se observó una mayor prevalencia de retraso en el crecimiento en el grupo rural, excepto para el grupo de edad de 15-18 años. La prevalencia de bajo peso fue significativamente mayor en el grupo rural (25% vs. 1,2%) así como la prevalencia del delgadez, excepto para el grupo de edad de 5-10 años. Conclusión: la alta prevalencia de bajo peso y la de sobrepeso/obesidad coexisten en los niños y adolescentes en Guatemala. PMID:27238797

  15. [Not Available].

    PubMed

    Santaliestra-Pasías, Alba M; Bel-Serrat, Silvia; Moreno, Luis A; Bueno, Gloria

    2016-07-12

    Introducción: la elevada prevalencia de obesidad en niños es un problema de salud global y conlleva el desarrollo de comorbilidades asociadas, como hipertensión, dislipemia, inflamación crónica e hiperinsulinemia, que a su vez son reconocidos factores de riesgo cardiovascular. Algunos estudios han observado que el consumo de productos lácteos podría ejercer un papel protector sobre el desarrollo de enfermedades cardiovasculares; sin embargo, la evidencia científica es bastante limitada en niños y adolescentes.Objetivos: investigar la relación entre el consumo de productos lácteos y factores de riesgo cardiovascular en poblaciones jóvenes.Material y métodos: se ha revisado la literatura reciente, incluyendo adicionalmente datos procedentes del estudio HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence). Se incluyó una muestra de adolescentes (12,5-17,5 años) provenientes de 8 ciudades europeas.Resultados: datos estadounidenses muestran una disminución en la frecuencia de consumo de leche, así como en el tamaño de la porción consumida. En el estudio HELENA los productos lácteos fueron el grupo de alimentos que mejor identificó a los adolescentes con bajo riesgo cardiovascular. Además, un consumo elevado de leche y yogur, así como de bebidas a base de leche y yogur, se asoció con niveles más bajos de grasa corporal, menor riesgo cardiovascular y mayor condición física cardiorrespiratoria.Conclusiones: son necesarios más estudios para proporcionar evidencia y comprender mejor los mecanismos subyacentes de la asociación entre la ingesta de lácteos, especialmente el yogur, y la obesidad, la diabetes, y otros factores de riesgo cardiovascular.

  16. [Phase angle as an indicator of nutritional status and prognosis in critically ill patients].

    PubMed

    Reis de Lima e Silva, Renata; Porto Sabino Pinho, Cláudia; Galvão Rodrigues, Isa; Gildo de Moura Monteiro Júnior, José

    2014-09-12

    Introducción: El ángulo de fase (AF) viene siendo considerado una herramienta sensible para evaluar el estado nutricional y la efectividad de las intervenciones dietoterápicas. Objetivo: Evaluar el AF como indicador del estado nutricional y pronóstico en pacientes críticos. Métodos: Estudio prospectivo observacional con pacientes admitidos en Unidades de Cuidado Intensivo Coronarias, entre Mayo y Octubre de 2013. El AF se determinó por medio del análisis por Bioimpedancia Eléctrica, considerándose bajo AF valores inferiores a 5º para los hombres y 4,6º para las mujeres. Los valores obtenidos se relacionaron con otros parámetros de evaluación del estado nutricional: antropométricos (circunferencia del brazo – CB, pliegue cutáneo triciptal – PCT, área muscular del brazo corregida - AMBc circunferencia de pantorrilla – CP) y bioquímico (recuento total de linfocitos, hemoglobina, hematocrito), además de los pronósticos clínicos APACHE II (Acute Physiology and Chronic Health Disease Classification System II) y albúmina sérica. La tabulación y análisis de los datos se realizaron a través del paquete estadístico SPSS versión 13.0. Resultados: La muestra se compuso por 110 pacientes, en la cual se verificó asociación entre bajo AF e insuficiencia renal en diálisis (p.

  17. ENDURANCE TRAINING IN FASTING CONDITIONS: BIOLOGICAL ADAPTATIONS AND BODY WEIGHT MANAGEMENT.

    PubMed

    Vicente-Salar, Néstor; Urdampilleta Otegui, Aritz; Roche Collado, Enrique

    2015-12-01

    Introducción: en la mayoría de las disciplinas deportivas, el deportista debe conseguir unas óptimas condiciones a nivel muscular y metabólico, así como de composición corporal, manteniendo un bajo porcentaje de grasa corporal. En este contexto se han propuesto diferentes protocolos de entrenamiento con el fin de reducir el porcentaje de grasa corporal incidiendo en un aumento de la utilización de las grasas en detrimento del glucógeno. Objetivo: comprobar si el entrenamiento en ayunas favorece el uso de ácidos grasos debido a los bajos niveles de glucógeno, permitiendo mejoras en el rendimiento y en el control del peso a partir de los estudios publicados. Resultados: los protocolos publicados difieren tanto en el periodo de trabajo como en la intensidad del ejercicio, así como respecto al análisis de una gran variedad de marcadores, desde la expresión de genes hasta parámetros circulantes. Discusión: a bajas intensidades de ejercicio aeróbico, los niveles de lipólisis y oxidación de grasas son mayores en el ejercicio en ayunas. Por otro lado, el metabolismo de la glucosa en condiciones de ayuno se adapta en relación al ahorro de las reservas de glucógeno. Finalmente, en condiciones de ayuno, la degradación de proteínas musculares se ve disminuida. Actualmente solo un estudio analiza los cambios en la composición corporal tras un protocolo de larga duración de ejercicio y ayuno, por lo que es necesario realizar más estudios con el fin de demostrar que se trata de una estrategia válida para el control del peso corporal.

  18. [Human milk in hospitalized premature neonates and nutritional evolution].

    PubMed

    Argüello, Carolina E; Defagó, María D

    2014-01-01

    Antecedentes: El nacimiento pretérmino es una emergencia nutricional y requiere consideraciones especiales. Objetivos: Se propuso evaluar el aporte de leche humana (LH) en el recién nacido prematuro hospitalizado de bajo peso (RNP-BP) y muy bajo peso (RNP-MBP), factores maternos y su relación con parámetros nutricionales. Materiales y métodos: Participaron 87 RNP-BP y 82 RNP-MBP admitidos en un hospital público en Córdoba, Argentina. Se registró la antropometría evolutiva, alimentación, parámetros bioquímicos, antecedentes del niño y maternos. Se calculó el aporte de LH. Se analizaron los valores antropométricos y bioquímicos, días de internación y factores maternos según aporte de LH. Resultados: El 36,36% de los RNP-MBP y el 31,02% de los RNP-BP cubrió más del 20% de su alimentación con LH. La hemoglobina sérica fue superior en RNP-MBP que recibieron más LH (p=0,01). Los RNP con menos del 20% de su alimentación con LH presentaron una asociación estadísticamente significativa entre la cantidad de LH y la talla al alta hospitalaria. Se observó una elevada prevalencia de cesáreas, asociada a un menor aporte de LH. Conclusiones: El aporte de LH contribuiría a estabilizar la hemoglobina en RNP. La presencia de cesárea podría asociarse a un menor aporte de LH a los RNP.

  19. [Imposex in Voluta musica (Caenogastropoda: Volutidae) from Northeastern Peninsula de Araya, Venezuela].

    PubMed

    Peralta, Ana Carolina; Miloslavich, Patricia; Bigatti, Gregorio

    2014-06-01

    Voluta musica is a dioecious marine gastropod endemic of the South Caribbean. Tributyltin (TBT) and copper (Cu) are potential inducers of imposex, an endocrine disorder by which females develop a penis and/or vas deferens. The goal of this work was to determine the imposex incidence in V. musica populations from Northeastern Peninsula de Araya. For this, we selected three sites (Isla Caribe, Isla Lobos and Bajo Cuspe) and made monthly samplings of 15 snails in each site, during one year, and determined: (1) sizes; (2) sex and imposex incidence and (3) the Relative Penis Length Index (RPLI). We also performed histological analysis of the gonads, and measured TBT and Cu concentrations in sediments from the studied localities. Our results showed that the total number of sampled females affected by imposex was 24.5% at Isla Caribe, 12% at Isla Lobos, and none at Bajo Cuspe. In sediments, Cu was detected mostly in Isla Lobos. The female gonads with imposex did not show any development of male cells in any of the sampled sites. The higher percentage of females with imposex matched with the higher boat traffic locality, and higher TBT level (Isla Caribe). No esterilization was evident in this work, nevertheless, the presence of TBT and Cu in the sediments and females with imposex were considered as a potential threat to V. musica populations in this region. In Venezuela there is no control over this particular issue, possibly because of the lack of information and research in this topic, but certainly, this information will be useful in biodiversity conservation policies. PMID:25102636

  20. [MEDICAGO SATIVA L: IMPROVEMENT AND NEW APPROACHES OF ITS NUTRITIONAL AND FUNCTIONAL VALUE BY BACTERIAL CO-INOCULATION].

    PubMed

    Martínez, Rosario; Nebot, Elena; Porres, Jesús María; Kapravelou, Garyfallia; Del Moral, Ana; Talbi, Chouhra; Bedmar, Eulogio Jose; López-Jurado, María

    2015-12-01

    Objetivo: estudiar el efecto de la inoculación con Ensifer meliloti y Halomonas maura sobre el crecimiento y el valor nutricional y funcional de la leguminosa Medicago sativa L., cultivada bajo condiciones de salinidad. Método: las plantas de M. sativa se cultivaron con una solución de mezcla de sales CaSO4, MgCl, NaCl and Na- HCO3 y se coinocularon con su rizobio específico y la bacteria H. maura. Se determinaron los parámetros fisiológicos de las plantas, así como el contenido en nitrógeno y minerales, y se llevó a cabo un proceso de digestibilidad in vitro. Resultados: la salinidad ejerció un efecto negativo sobre las plantas; sin embargo, la coinoculación de las mismas incrementó su productividad, el contenido en nitrógeno, minerales totales, Ca y Mg. Además, los parámetros fisiológicos de potencial hídrico y concentración de leghemoglobina se incrementaron. Tanto la salinidad como la coinoculación de las plantas aumentaron la capacidad antioxidante de la leguminosa en los dializados y retenidos obtenidos tras someter a la planta a un proceso de digestibilidad in vitro. Conclusión: la coinoculación con E. meliloti y H. maura podría mejorar el cultivo de la alfalfa bajo condiciones específicas de salinidad, aumentando su composición nutricional y funcional, pudiendo considerarse en la formulación de suplementos nutricionales para el consumo humano.

  1. Dairy products consumption versus type 2 diabetes prevention and treatment; a review of recent findings from human studies.

    PubMed

    Cândido, Flávia Galvão; Ton, Winder Tadeu Silva; Alfenas, Rita de Cássia Gonçalves

    2013-01-01

    Introducción: Se ha afirmado que el consumo adecuado de los productos lácteos puede ser beneficioso para la prevención y el tratamiento de la diabetes mellitus tipo 2 (DMT2). Objetivos: El objetivo de esta revisión es analizar críticamente la principal evidencia científica sobre este tema. Métodos: MEDLINE, PubMed, Science Direct, SCIELO y LILACS fueron consultadas para estudios publicados en los últimos 12 años explorando los efectos del consumo de productos lácteos o sus componentes (calcio, vitamina D y magnesio) en la DMT2. Resultados y discusión: Los estudios epidemiológicos indican que el consumo de por lo menos tres porciones de productos lácteos bajos en grasa al día como parte de una dieta saludable, es crucial para reducir el riesgo de desarrollar DMT2. La mayoría de los estudios de intervención analizados reportaron efectos benéficos del aumento del calcio y de la ingestión de vitamina D en la mejora de la sensibilidad a la insulina y la prevención de DMT2. Conclusiones: Aunque el impacto del consumo de productos lácteos para tratar DMT2 necesita más investigación, el consumo de productos lácteos bajos en grasa puede ser una importante estrategia para prevenir y controlar la DMT2.

  2. [FOOD PATTERNS ASSOCIATED WITH A HEALTY BODY WEIGHT IN CHILEAN STUDENTS OF NUTRITION AND DIETETICS].

    PubMed

    Durán Agüero, Samuel; Fernández Godoy, Eloina; Fuentes Fuentes, Jessica; Hidalgo Fernández, Andrea; Quintana Muñoz, Carol; Yunge Hidalgo, Wilma; Fehrman Rosas, Pamela; Delgado Sánchez, Claudia

    2015-10-01

    Objetivo: determinar los patrones de alimentación y asociar el consumo de diversos alimentos con el estado nutricional de estudiantes universitarios chilenos de Nutrición y Dietética. Material y métodos: estudio transversal. Se evaluaron 634 estudiantes de Nutrición y Dietética de la Universidad San Sebastián de las ciudades de Santiago, Concepción, Valdivia y Puerto Montt. A cada estudiante se le aplicó una encuesta alimentaria y se le realizó una evaluación antropométrica. Resultados: el 68% de los estudiantes consume desayuno diariamente, 36,1% y 37,1% consume las porciones recomendadas de frutas y verduras, el 64,9% consume bebidas azucaradas frecuentemente. Se observa una asociación entre un buen peso corporal y el consumo de verduras (≥ 2 porciones/día) OR = 0,662 (0,440-0,996), alimentos integrales OR = 0,474 (0,224-1,002) y un bajo consumo de frituras y snack dulces OR = 0,643 (0,406- 1,019) y OR = 0,545 (0,360-0,825), respectivamente. Conclusiones: los estudiantes presentan una ingesta insuficiente de alimentos saludables y un elevado consumo de alimentos poco saludables, además se observa que la ingesta de verduras y cereales integrales, así como un bajo consumo de frituras y bocadillos dulces se asocian a un estado nutricional normal en los estudiantes evaluados.

  3. Abundance, behavior and entomological inoculation rates of anthropophilic anophelines from a primary Colombian malaria endemic area

    PubMed Central

    2013-01-01

    Background In Colombia for several years, the Urabá-Bajo Cauca and Alto Sinú region has registered the highest numbers of malaria cases in the country. Malaria vector incrimination and the characterization of entomological parameters will allow for a better understanding of malaria transmission dynamics and the design of effective vector control strategies for this region. Methods We conducted a longitudinal survey between November 2008 and June 2010 to quantify entomological (abundance and biting activity) and transmission parameters, including infection rate (IR) and entomological inoculation rate (EIR), to incriminate potential anopheline vectors in three localities of a major Colombian malaria endemic region, the Urabá-Bajo Cauca and Alto Sinú: La Capilla, Juan Jose and El Loro. Results A total of 5,316 anopheline mosquitoes corresponding to seven species were collected. Anopheles nuneztovari (69.5%) and Anopheles darlingi (22.2%) were the most abundant species, followed by Anopheles pseudopunctipennis (4.5%), Anopheles albitarsis s.l. (2%), Anopheles triannulatus lineage Northwest (1.8%), Anopheles punctimacula and Anopheles argyritarsis (at < 1%, each). Three species were naturally infected with Plasmodium vivax, An. nuneztovari, An. darlingi (IRs < 1%) and An. triannulatus (IR = 1.5%). Annual EIRs for these species ranged from 3.5 to 4.8 infective bites per year. Conclusions These results indicate that An. nuneztovari and An. darlingi continue to be the most important malaria vectors in this region. Anopheles triannulatus, a species of local importance in other South American countries was found naturally infected with Plasmodium vivax VK247; therefore, further work should be directed to understand if this species has a role in malaria transmission in this region. PMID:23497535

  4. Alteration patterns of chromian spinels from La Cabaña peridotite, south-central Chile

    NASA Astrophysics Data System (ADS)

    Barra, Fernando; Gervilla, Fernando; Hernández, Elkin; Reich, Martin; Padrón-Navarta, José Alberto; González-Jiménez, José Maria

    2014-12-01

    La Cabaña peridotite is part of a dismembered ophiolite complex located within the metamorphic basement of the Coastal Cordillera of south-central Chile, and is the only location in Chile were Cr-spinels have been described so far. The La Cabaña peridotite is part of the Western Series unit, which comprises meta-sedimentary rocks, metabasites, and serpentinized ultramafic rocks. This unit has been affected by greenschist-facies metamorphism with reported peak PT conditions of 7.0-9.3 kbar and 380°-420 °C. Within La Cabaña peridotite Cr-spinels are present in two localities: Lavanderos and Centinela Bajo. In Lavanderos, Cr-spinel occurs in small chromitite pods and as accessory/disseminated grains with a porous or spongy texture in serpentinite, whereas in Centinela Bajo Cr-spinel is present as accessory zoned grains in partly serpentinized dunites, and in chromitite blocks. All Cr-spinels display variable degrees of alteration to Fe2+-rich chromite with a variation trend of major elements from chromite to Fe2+-rich chromite similar to those observed in other locations, i.e., an increase in Fe2O3 and FeO, a decrease in Al2O3 and MgO. Cr2O3 content increases from chromite to Fe2+-rich chromite in chromitite pods from Lavanderos and chromitite blocks from Centinela Bajo, but decreases in ferrian chromite zones in accessory grains from Centinela Bajo. The minor element (Ti, V, Zn, Ni) content is mostly low and does not exceed 0.4 wt.%, with the exception of MnO (<0.9 wt.%), which shows a correspondence with increasing degree of alteration. Cr# (Cr/Cr + Al) versus Mg# (Mg/Mg + Fe2+) and Fe3+/Fe3++Fe2+ versus Mg# plots are used to illustrate the Cr-spinel alteration process. Overall, the Cr-spinels from Lavanderos (chromitite pods and disseminated grains) exhibit Cr# values ranging from 0.6 to 1.0, Mg# (Mg/Mg + Fe2+) below 0.5, and (Fe3+/Fe3++Fe2+) <0.4. Cr-spinels from chromitites in Centinela Bajo have Cr# and Mg# values that range from 0.65 to 1.0, and 0

  5. [EFFICIENCY OF HAEMOGLOBIN REGENERATION IN THE NUTRITIONAL FERROPENIC ANAEMIA RECOVERY WITH GOAT MILK-BASED DIETS].

    PubMed

    Serrano Reina, José Antonio; Nestares Pleguezuelo, Teresa; Muñoz Alférez, Ma José; Díaz Castro, Javier; López Aliaga, Ma Inmaculada

    2015-10-01

    Objetivo: a pesar de la alta incidencia de anemia ferropénica y de los efectos beneficiosos derivados del consumo de leche de cabra, poco se conoce, en realidad, acerca de la recuperación de la anemia mediante una dieta equilibrada acompañada de la ingesta de leche de cabra. El objetivo del presente estudio es determinar, en ratas con anemia ferropénica nutricional, los efectos de dietas elaboradas a base de leche de cabra, en comparación con la de vaca, suministradas durante 30 días, sobre la recuperación de la anemia y la eficacia de regeneración de la hemoglobina. Material y métodos: se han utilizado 40 ratas macho Wistar albina recién destetadas divididas al azar en dos grupos experimentales y alimentadas ad libitum durante 40 días con dieta AIN-93G con contenido normal de hierro (grupo control, 45 mg/kg dieta), o bajo (grupo anémico, 5 mg/kg dieta). Se toman muestras de sangre de la vena caudal para el control hematológico de la anemia. Posteriormente, cada uno de los dos grupos experimentales (control y ferrodeficiente) fueron alimentados durante 30 días con dietas elaboradas a base de leche de cabra o vaca. Al finalizar el período experimental y previa anestesia, las ratas se desangran por canulación de la aorta abdominal, y la sangre obtenida se recoge en un tubo con EDTA como anticoagulante para la posterior determinación de los parámetros hematológicos y la eficacia de regeneración de la hemoglobina. Resultados y discusión: tras el consumo de una dieta con bajo contenido en hierro durante 40 días, las ratas eran anémicas, con una concentración de hemoglobina, hematocrito, hierro sérico, volumen corpuscular medio (VCM), ferritina sérica y saturación de la transferrina bajos (p < 0,001), mientras que los niveles de plaquetas y la capacidad total de unión al hierro (TIBC) estaban elevados (p < 0,001), hallazgos consistentes con la anemia inducida experimentalmente en ratas. La eficacia de regeneración de la hemoglobina era mayor

  6. [In Process Citation].

    PubMed

    Guzmán-Mercado, Elizabeth; Vásquez-Garibay, Edgar M; Troyo-Sanroman, Rogelio; Romero-Velarde, Enrique

    2016-03-25

    Objetivo: identificar los hábitos alimentarios de adolescentes embarazadas en cuatro estados civiles diferentes: casada, cohabita con una pareja, soltera sin pareja y soltera con una pareja. Métodos: en estudio transversal, se incluyeron 321 adolescentes embarazadas de 13-19 años que acudieron al Hospital Civil de Guadalajara Dr. Juan I Menchaca, Guadalajara (Jalisco, México). Se encontraban sanas, en cualquier trimestre del embarazo y pertenecían a un nivel socioe-conómico bajo o medio-bajo. El estado civil se estratificó en: casadas; en unión libre; soltera con una pareja y soltera sin pareja. Se incluyeron datos socio-demográficos, económicos y de hábitos de alimentación. Se utilizaron pruebas de ANOVA, pruebas post-hoc para Chi 2 , razón de momios y modelos de regresión logística. Resultados: la frecuencia de las adolescentes casadas fue de 9,3%, 59,8% en unión libre, 15,3% eran solteras sin pareja y 15,6% solteras con pareja. La baja escolaridad (RM 2,6 [1,5-4,4]) y la ocupación en el hogar (RM 4,47 [1,99-10,0]) predominaron entre las adolescentes en unión libre; la ocupación en el hogar (RM 0,28 [0,127-0,61]) y cenar sin compañía (RM 4,12 [1,62-10,8]) fueron significativamente más frecuentes en adolescentes sin pareja. El consumo de verduras fue menor en las adolescentes casadas y en quienes cohabitaban con pareja; el consumo de frijoles y pan dulce fue menor en adolescentes embarazadas casadas. Conclusión: debido a que ciertas variables y hábitos de alimentación mostraron diferencias entre los grupos es pertinente analizar las adolescentes embarazadas de acuerdo a su estado civil.

  7. Late referral for chronic kidney disease patients: nutritional point of view.

    PubMed

    Guerra, Daiane Cristina; Rodrigues Neto Angéloco, Larissa; Furtado, Wander R; Barbosa Coelho, Eduardo; Garcia Chiarello, Paula

    2014-09-12

    La prevalencia de la referencia tardía de los pacientes con enfermedad renal crónica (ERC) es alta y se ha asociado con un pronóstico peor ERC, sin embargo pocos estudios se han llevado a cabo desde una perspectiva nutricional. Objetivo: Caracterizar el estado nutricional de los pacientes con ERC con la primera cita en un servicio de nefrología, con temprana (ER) y la remisión tardía (LR). Metodología: Se realizó un estudio transversal con pacientes mayores de 18 años a que se refiere el servicio de Nefrología del Hospital Universitario. Los grupos de referencia se clasificaron de acuerdo a la tasa estimada de filtración glomerular (TFG) como: LR (TFG 15 ml / min / 1.73m2), basado en la Kidney Disease Outcomes Quality Initiative. Evaluación nutricional incluyó la evaluación subjetiva global (SGA), antropométricas, de laboratorio y los datos de impedancia bioeléctrica. El software de SAS ® se utilizó para el análisis estadístico. Resultados: Fueron evaluados setenta y cinco pacientes, el 29% de ellos pertenece al grupo LR. Este grupo mostró una pérdida mayor de peso anterior (-7,0 ± 3,5 frente a -2,8 ± 7,0 Kg) y los valores más bajos para todas las variables antropométricas y de composición corporal. En general, los resultados de laboratorio del grupo LR también eran peores. De acuerdo con el SGA, todos los pacientes tenían LR algún grado de desnutrición (50% con desnutrición severa contra 28,8% en ER), que muestra resultados significativamente más bajos de la TFG (21,4 + 12,2 ml / min / 1,73 m2), albúmina (3,9 + 0,3 g / dL), bicarbonato sérico (22,8 + 5,1 mmol / L) y ángulo de fase (5.3+ 0,6 ). La función renal se correlacionó positivamente con el porcentaje de adecuación de la circunferencia del brazo (r=0,40; p.

  8. Prevalence of underweight, overweight and obesity in university students from the region of Anhui (China).

    PubMed

    Ren, Xiaohua; Chen, Yan; He, Lianping; Jin, Yuelong; Tian, Li; Lu, Mi; Lu, Wei; Ding, Lingling; Guo, Daoxia; Wang, Linghong; Nie, Zhognhua; Yao, Yingshui

    2014-12-16

    Antecedentes: El sobrepeso y la obesidad son epidemia en todo el mundo.Nuestro estudio anterior halló que la prevalencia de sobrepeso y obesidad en estudiantes de primaria es alto. Objetivo: Hemos tratado de estimar si la prevalencia del sobrepeso y la obesidad entre los estudiantes universitarios es todavía alta en China. Métodos: Un estudio transversal fue diseñado para recoger los exámenes de salud de rutina datos para estudiantes universitarios en 2013.La altura y el peso de los estudiantes fueron medidos, y el IMC se calcula con la altura y el peso, así como para estimar la prevalencia de insuficiencia ponderal y obesidad de la Universidad los estudiantes utilizando dos referencias [Grupo de trabajo sobre la obesidad referencias en China (2004) y la Organización Mundial de la salud (OMS) criterios (2000)]. Resultados: Dependiendo de la China referencias utilizadas, la prevalencia global de bajo peso, sobrepeso (obesidad) y la obesidad en estudiantes universitarios masculinos fueron 14,2%, el 14,7% y 4,2%, respectivamente; en mujeres estudiantes universitarios fueron el 27,5%, 4,4% y 0,6%, respectivamente. Dependiendo de los que referencias utilizadas, la prevalencia global de bajo peso, sobrepeso (obesidad) y la obesidad en estudiantes universitarios masculinos fueron 14,2%, 11,5% y 2,5%, respectivamente, en mujeres estudiantes universitarios fueron el 27,5%, 2,4% y 0,3%, respectivamente.Una observación interesante es que la prevalencia de insuficiencia ponderal de los estudiantes universitarios tiene una tendencia al aumento, sobre todo en mujeres. Conclusión: El estudio demostró que la prevalencia de la insuficiencia ponderal en estudiantes universitarios, especialmente en mujeres estudiantes se ha convertido en un problema de salud crítico.Related Departamento de la escuela y el Gobierno deben prestar más atención a la salud física del alumno.

  9. [ASSOCIATION BETWEEN FITNESS, NUTRITIONAL STATUS AND ACADEMIC PERFORMANCE IN PHYSICAL EDUCATION STUDENTS].

    PubMed

    Godoy Cumillaf, Andrés; Valdés Badilla, Pablo; Fariña Herrera, Custodio; Cárcamo Mora, Francisco; Medina Herrera, Bernice; Meneses Sandoval, Elías; Gedda Muñoz, Relmu; Durán Agüero, Samuel

    2015-10-01

    Introducción: diversas investigaciones han señalado que la práctica regular de ejercicio físico impactaría positivamente sobre el rendimiento académico de los estudiantes. Objetivo: determinar la asociación entre la condición física, el estado nutricional y el rendimiento académico de estudiantes de Pedagogía en Educación Física de Temuco, Chile. Material y métodos: la muestra fue seleccionada bajo un criterio no probabilístico, que incluyó 208 sujetos (n = 153 hombres y n = 55 mujeres). Las variables estudiadas correspondieron a la condición física (abdominales cortos, salto largo a pies juntos, flexión de tronco adelante, flexo-extensión de codos y test course navette), estado nutricional (índice de masa corporal –,IMC) y rendimiento académico (sobre el promedio y bajo el promedio). Resultados: un 87,5% de los estudiantes presentan una condición física satisfactoria y un IMC promedio de 23,8 ± 2,9 kg/m2, siendo aquellos que alcanzan mejores valores de rendimiento académico los que poseen también mayor proporción de condición física satisfactoria (92,5%). Al realizar la asociación entre las variables estudiadas, no hubo asociación entre rendimiento académico y estado nutricional, pero sí entre baja condición física y un mayor riesgo de presentar un menor rendimiento académico (OR = 2,8; IC95%:1,0-8,1; p < 0,05). Conclusión: se observa una asociación entre rendimiento académico y condición física entre los estudiantes, pero no se asocia el estado nutricional con el rendimiento académico.

  10. [In Process Citation].

    PubMed

    Martín Álvarez, Estefanía; Jiménez Cabanillas, María Victoria; Peña Caballero, Manuela; Serrano López, Laura; Kajarabille, Naroa; Díaz Castro, Javier; Ochoa Herrera, Julio José; Maldonado Lozano, José

    2016-01-01

    Introducción: el recién nacido prematuro de muy bajo peso (RNMBP) es inmunológicamente inmaduro y además presenta una alteración de las barreras naturales de defensa. Objetivo: evaluar los efectos que pueda tener la administración de calostro orofaríngeo, administrado durante los primeros 15 días posnatales, sobre los niveles de inmunoglobulina A (IgA) sérica en recién nacidos prematuros de muy bajo peso durante el primer mes de vida. Material y métodos: se desarrolló un estudio de intervención no aleatorizado con grupo control, en el que se incluyeron 38 recién nacidos con ≤ 32 + 6 semanas de gestación y/o menores de 1.500 g de peso. Los sujetos recibieron 0,2 ml de calostro de su madre cada 4 h, iniciándose el procedimiento en las primeras 24 h de vida hasta el 15.o día postnatal. Se midieron los niveles de IgA en la sangre al nacimiento, 3. er , 15.o y 30.o días de vida. Se registraron datos perinatales al nacimiento y durante el periodo de seguimiento. Resultados: IgA sérica aumentó de forma estadísticamente significativa en el grupo de intervención (M1 15,84 μg/ml, M2 20,07 μg/ml, M3 23,65 μg/ml, M4 30,34 μg/ml, p 0,001) y en el grupo control (M1 12,48 μg/ml, M2 16,48 μg/ml, p 0,018; M3 19,41 μg/ml, M4 22,48 μg/ml, p 0,001). Al mes de vida, los niveles de IgA sérica fueron significativamente mayores en el grupo de intervención que en el grupo control (p 0,026). Conclusiones: este estudio sugiere que la administración de calostro orofarínge. PMID:27238778

  11. [Seroprevalence of antinuclear antibodies in blood donors in the Yaqui Valley].

    PubMed

    Serrano-Osuna, Ricardo; López-López, Rocío Milagro; Brito-Zurita, Olga Rosa; Sabag-Ruiz, Enrique; Pérez-Fernández, Héctor; Ornelas-Aguirre, José Manuel

    2014-01-01

    Antecedentes: los anticuerpos antinucleares son inmunoglobulinas que reconocen componentes celulares nucleares y citoplasmáticos autólogos. En personas sanas no se relacionan con alguna enfermedad autoinmune; sin embargo, pueden estar vinculados con un fenotipo inmunológico de riesgo que no ha sido suficientemente estudiado. Objetivo: examinar la existencia de anticuerpos antinucleares en el suero de donadores de sangre. Material y métodos: estudio transversal y analítico en búsqueda de anticuerpos antinucleares en suero mediante inmunofluorescencia indirecta en células HEp-2. La prevalencia y patrón de expresión se contrastaron con la edad, el género y los antecedentes de enfermedad reumática o tiroidea. Resultados: se estudiaron 379 donadores de sangre con límites de edad entre 18 y 65 años. La prevalencia de anticuerpos antinucleares en la población estudiada fue de 13%. La mayoría de los sujetos positivos tenía entre 21 y 40 años de edad. El género masculino expresó mayor proporción de positividad (11%) en comparación con las mujeres (2%). De la misma forma, 82% de los hombres tenía títulos bajos (1:80) y en 66% eran de tipo nucleolar (RM = 10.66 [1.83 a 62.18]; p = 0.007). Conclusiones: en individuos sanos, la existencia de anticuerpos antinucleares a títulos bajos puede no significar un estado de autoinmunidad; sin embargo, podría ser el reflejo de una exposición a factores ambientales que no han sido lo suficientemente estudiados. Es necesario realizar nuevos estudios en población sana que permitan explicar la asociación entre estos anticuerpos y los factores tóxicoambientales, así como sus efectos en la salud.

  12. Fault kinematics and depocenter evolution of oil-bearing, continental successions of the Mina del Carmen Formation (Albian) in the Golfo San Jorge basin, Argentina

    NASA Astrophysics Data System (ADS)

    Paredes, José Matildo; Plazibat, Silvana; Crovetto, Carolina; Stein, Julián; Cayo, Eric; Schiuma, Ariel

    2013-10-01

    Up to 10% of the liquid hydrocarbons of the Golfo San Jorge basin come from the Mina del Carmen Formation (Albian), an ash-dominated fluvial succession preserved in a variably integrated channel network that evolved coeval to an extensional tectonic event, poorly analyzed up to date. Fault orientation, throw distribution and kinematics of fault populations affecting the Mina del Carmen Formation were investigated using a 3D seismic dataset in the Cerro Dragón field (Eastern Sector of the Golfo San Jorge basin). Thickness maps of the seismic sub-units that integrate the Mina del Carmen Formation, named MEC-A-MEC-C in ascending order, and mapping of fluvial channels performed applying geophysical tools of visualization were integrated to the kinematical analysis of 20 main normal faults of the field. The study provides examples of changes in fault throw patterns with time, associated with faults of different orientations. The "main synrift phase" is characterized by NE-SW striking (mean Az = 49°), basement-involved normal faults that attains its maximum throw on top of the volcanic basement; this set of faults was active during deposition of the Las Heras Group and Pozo D-129 formation. A "second synrift phase" is recognized by E-W striking normal faults (mean Az = 91°) that nucleated and propagated from the Albian Mina del Carmen Formation. Fault activity was localized during deposition of the MEC-A sub-unit, but generalized during deposition of MEC-B sub-unit, producing centripetal and partially isolated depocenters. Upward decreasing in fault activity is inferred by more gradual thickness variation of MEC-C and the overlying Lower Member of Bajo Barreal Formation, evidencing passive infilling of relief associated to fault boundaries, and conformation of wider depocenters with well integrated networks of channels of larger dimensions but random orientation. Lately, the Mina del Carmen Formation was affected by the downward propagation of E-W to ESE-WNW striking

  13. [Factors associated with mortality in patients with dysphagia help in making dietary and nutritional choices].

    PubMed

    Ferrero López, María Isabel; De la Rubia Ortí, José Enrique; Castellano Vela, Enrique; González Monte, Carmen; Sanchis-Bayarri Bernal, Vicente; Navarro Sanz, Ramón

    2014-01-01

    Objetivo: Conocer en los pacientes con disfagia ingresados en un Hospital de Media y Larga Estancia, qué factores, valorados al ingreso, están relacionados con fallecer durante su hospitalización y pueden orientar la intervención dietética y nutricional. Material y método: Estudio de cohorte retrospectivo, observacional y descriptivo de pacientes diagnosticados de disfagia por el Método de Exploración Clínica Volumen- Viscosidad (MECVV). Se recogieron variables demográficas y clínicas, estancia, éxitus, revaloraciones de disfagia y tratamientos. Resultados: Se incluyeron 182 pacientes, con edad media de 78 años, fallecieron el 50%. En el análisis univariante se asociaron significativamente con el éxitus: edad >= 85 años, diagnóstico previo de disfagia, padecer enfermedad oncológica, elevada comorbilidad (Charlson entre 2-5 y > 5 puntos), baja funcionalidad previa a hospitalización (Índice de Barthel < 40 puntos), MNA < 17 puntos, albúmina < 3 g/dl, alta puntuación del CONUT (de 5-12 puntos), tratamiento con: opioide, neuroléptico o antidepresivo al realizar el MECVV, y objetivo asistencial al ingreso. En análisis multivariante obtuvieron significación: edad, enfermedad oncológica, comorbilidad, y albúmina como factores de riesgo para fallecer, y llevar antidepresivo como factor protector. Se aplicó análisis de contraste con Curva ROC. El área bajo la curva fue 0,740 y el intervalo de confianza (IC) 0,668-0,811. Conclusiones: En pacientes con disfagia, los datos referidos valorados al ingreso, pueden ayudar a definir más adecuada y precozmente objetivos asistenciales. En los casos con mayor riesgo de fallecer se priorizará una ingesta segura y de confort, y en aquellos con bajo riesgo, además deberá ser eficaz para intentar mejorar al máximo su estado nutricional.

  14. [In Process Citation].

    PubMed

    Guzmán-Mercado, Elizabeth; Vásquez-Garibay, Edgar M; Troyo-Sanroman, Rogelio; Romero-Velarde, Enrique

    2016-01-01

    Objetivo: identificar los hábitos alimentarios de adolescentes embarazadas en cuatro estados civiles diferentes: casada, cohabita con una pareja, soltera sin pareja y soltera con una pareja. Métodos: en estudio transversal, se incluyeron 321 adolescentes embarazadas de 13-19 años que acudieron al Hospital Civil de Guadalajara Dr. Juan I Menchaca, Guadalajara (Jalisco, México). Se encontraban sanas, en cualquier trimestre del embarazo y pertenecían a un nivel socioe-conómico bajo o medio-bajo. El estado civil se estratificó en: casadas; en unión libre; soltera con una pareja y soltera sin pareja. Se incluyeron datos socio-demográficos, económicos y de hábitos de alimentación. Se utilizaron pruebas de ANOVA, pruebas post-hoc para Chi 2 , razón de momios y modelos de regresión logística. Resultados: la frecuencia de las adolescentes casadas fue de 9,3%, 59,8% en unión libre, 15,3% eran solteras sin pareja y 15,6% solteras con pareja. La baja escolaridad (RM 2,6 [1,5-4,4]) y la ocupación en el hogar (RM 4,47 [1,99-10,0]) predominaron entre las adolescentes en unión libre; la ocupación en el hogar (RM 0,28 [0,127-0,61]) y cenar sin compañía (RM 4,12 [1,62-10,8]) fueron significativamente más frecuentes en adolescentes sin pareja. El consumo de verduras fue menor en las adolescentes casadas y en quienes cohabitaban con pareja; el consumo de frijoles y pan dulce fue menor en adolescentes embarazadas casadas. Conclusión: debido a que ciertas variables y hábitos de alimentación mostraron diferencias entre los grupos es pertinente analizar las adolescentes embarazadas de acuerdo a su estado civil. PMID:27238777

  15. Metabolic syndrome components can predict C reactive protein concentration in adolescents.

    PubMed

    da Cruz, Larissa Leandro; Cardoso, Luciane Daniele; Pala, Daniela; de Paula, Heberth; Lamounier, Joel Alves; Silva, Camilo Adalton Mariano; Volp, Ana Carolina Pinheiro; de Freitas, Renata Nascimento

    2013-01-01

    Antecedentes: El síndrome metabólico (SM) se sugiere que está asociada con un estado de inflamación crónica de bajo grado, pero la relación entre biomarcadores de inflamación crónica de bajo grado, pero la relación entre biomarcadores de inflamación y los componentes del síndrome metabólico en adolescentes son escasos. Objetivo: Investigar la asociación entre las concentraciones séricas de proteína C reactiva (CRP) y los componentes del síndrome metabólico en adolescentes. Metodología: Hemos realizado una población basada en estudio de corte transversal. Los datos antropométricos, bioquímicos y clínicos se obtuvieron de 524 adolescentes (11-15 años de edad) seleccionados al azar de la población escolar de la ciudad Alegre, Espírito Santo, Brasil. Los datos fueron analizados por STATA versión 9.0. Resultados: Los adolescentes, con valores más altos de IMC (p = 0,001) y mayor porcentaje de grasa corporal (p = 0,003) tuvieron mayores concentraciones de PCR que aquellos con menor IMC y porcentaje de grasa corporal. Las concentraciones de PCR se correlacionó directamente con el IMC (r = 0,17, p = 0,0001), la circunferencia de la cintura (r = 0,15, p = 0,0005), HDL-c (r = 0,13, p = 0,003), la insulina en ayunas (r = 0,12, p = 0,009) y la presión arterial sistólica (r = 0,11, p = a 0,01). En el análisis de regresión lineal múltiple IMC (r = 0,05, p = 0,002), la glucosa en ayunas (r = -0,01, p = 0,003) y HDL-c (r = 0,017, p < 0,001) se asociaron a las concentraciones de PCR después de ajustar por los otros componentes de SM. Conclusión: La asociación encontrada entre los componentes individuales de SM y las concentraciones de PCR sugiere que la inflamación podría ser un evento temprano en el desarrollo de trastornos metabólicos en los adolescentes.

  16. Design and methods of the GLYNDIET study; assessing the role of glycemic index on weight loss and metabolic risk markers.

    PubMed

    Juanola-Falgarona, Martí; Ibarrola-Jurado, Núria; Salas-Salvadó, Jordi; Rabassa-Soler, Antoni; Bulló, Mònica

    2013-01-01

    Introducción: El índice glucémico y la carga glucémica se han postulado como una alternativa para la prevención y/o el manejo de la obesidad, enfermedades cardiovasculares, diabetes mellitus tipo 2 y cáncer. Objetivo: Describir el diseño y los métodos utilizados en el proyecto GLYNDIET, un estudio diseñado para evaluar el papel del índice glucémico sobre la pérdida de peso corporal, la saciedad, la inflamación y marcadores de riesgo metabólico. Métodos: Ensayo clínico, en paralelo, controlado, aleatorizado y de 6 meses de duración realizado en hombres y mujeres de entre 30 y 60 AÑOs, con un índice de masa corporal de entre 27 y 35 kg/m2. Los sujetos fueron asignados aleatoriamente a una de las 3 intervenciones (dieta con carbohidratos de bajo índice glucémico, dieta con carbohidratos de alto índice glucémico o dieta baja en grasa). Los sujetos fueron citados mensualmente para realizar visitas control en las que se recogían datos a antropométricos, de presión arterial, hábitos dietéticos, sensación de saciedad y grado de actividad física. Al inicio y al final del estudio se recogieron muestras sanguíneas, urinarias y de tejido adiposo subcutáneo mediante biopsia abdominal. Discusión: El estudio GLYNDIET se diseñó con el objetico de determinar si el consumo de una dieta con carbohidratos de bajo índice glucémico muestra una mayor efectividad sobre la pérdida de peso corporal y la modulación de factores de riesgo metabólico en comparación a una dieta con carbohidratos de alto índice glucémico o una dieta baja en grasas.

  17. [VITAMIN D DEFICIENCY AMONG CHILDREN AND ADOLESCENTS WITH NORMAL NUTRITIONAL STATUS].

    PubMed

    Durá-Travé, Teodoro; Gallinas-Victoriano, Fidel; Chueca Guindulain, María Jesús; Berrade-Zubiri, Sara

    2015-09-01

    Objetivo: analizar la prevalencia de la deficiencia de vitamina D a lo largo de un año natural en una población pediátrica con un estado nutricional normal. Material y métodos: estudio transversal clínico y analítico (calcio, fósforo, fosfatasa alcalina, calcidiol y hormona paratiroidea) en 413 sujetos (entre 3,1 y 15,4 años): 227 escolares (96 varones y 131 mujeres) y 186 adolescentes (94 varones y 92 mujeres), de raza caucásica y estado nutricional normal, durante el año 2014. Para definir la deficiencia de vitamina D se han aplicado los criterios de la Sociedad Americana de Endocrinología. Resultados: los niveles de calcidiol eran más bajos en primavera (25,96 ± 6,64 ng/ml) y alcanzaban su máximo nivel en verano (35,33 ± 7,51 ng/ml); mientras que los de PTH eran más bajos en verano (27,13 ± 7,89 pg/ml) y alcanzaban su máximo nivel en otoño (34,73 ± 15,38 pg/ml). La prevalencia de deficiencia de vitamina D era del 14,3% en verano y del 75,3% en primavera. En 8 casos (1,9%) existían cifras de PTH compatibles con hiperparatiroidismo secundario. Existía una correlación negativa entre calcidiol y PTH (p < 0,01). No existía correlación entre IMC y calcidiol. Conclusión: en la población pediátrica con una situacion nutricional normal existe una alta prevalencia de deficiencia de vitamina D en los meses de otoño e invierno y, especialmente, en primavera, y habría que considerar la necesidad de administrar suplementos vitamínicos y/o ingerir mayores cantidades de sus fuentes dietéticas naturales.

  18. [Obesity associated metabolic impairment is evident at early ages: Spanish collaborative study].

    PubMed

    Martos-Moreno, Gabriel Á; Gil-Campos, Mercedes; Bueno, Gloria; Bahillo, Pilar; Bernal, Susana; Feliu, Albert; Lechuga-Sancho, Alfonso M; Palomo, Enrique; Ruiz, Rafael; Vela, Amaia

    2014-10-01

    Los objetivos de este estudio son, realizar una descripción de las características demográficas, antropométricas y de las alteraciones metabólicas de niños atendidos por obesidad resaltando las características aquellos casos de obesidad de inicio temprano (< 10 años) y los de inicio precoz (< 5 años), y evaluar la capacidad diagnóstica de la definición de síndrome metabólico (SM) según diferentes criterios. Métodos: Es un estudio retrospectivo, caso-control, transversal, multicéntrico. Han participado un total de 10 Unidades de Endocrinología Pediátrica de diferentes hospitales españoles con un grupo de 469 niños con obesidad de inicio temprano y otro grupo de 30 niños con obesidad de inicio precoz. El grupo control estuvo constituido por 224 niños sanos menores de 10 años. Se realizó una valoración antropométrica y determinación analítica de parámetros del metabolismo de los hidratos de carbono y lipidograma. Resultados: La presencia de alteraciones metabólicas asociadas a la obesidad en la etapa infanto-juvenil en España es notable, de forma aislada, o englobada bajo la definición de SM. La prevalencia de éste aumenta sustancialmente cuando se considera la resistencia periférica a la acción de la insulina como criterio diagnóstico. Se demuestra cómo en niños menores de 10 años, dichas alteraciones están presentes en un porcentaje reseñable, y se encuentran las primeras alteraciones metabólicas ya en niños obesos < 5 años. Conclusión: En los niños españoles existen alteraciones metabólicas asociadas a la obesidad en la etapa infanto- juvenil de forma aislada o englobada bajo la definición de SM, y ya están presentes a edades precoces.

  19. SELENIUM IN DYSPHAGIC PATIENTS WHO UNDERWENT ENDOSCOPIC GASTROSTOMY FOR LONG TERM ENTERAL FEEDING.

    PubMed

    Santos, Carla Adriana; Fonseca, Jorge; Carolino, Elisabete; Lopes, Teresa; Guerreiro, António Sousa

    2015-12-01

    Introducción y objetivos: los pacientes con gastrostomía endoscópica (GEP) presentan malnutrición calórica- proteica, pero poco se conoce sobre la deficiencia de selenio. Estudiamos la evolución del selenio sérico en el momento de la GEP y después 4 y 12 semanas. Además, evaluamos la evolución de albúmina, transferrina, índice de masa corporal (IMC) y la influencia de la enfermedad subyacente. Métodos: obtenemos una muestra de sangre antes de la gastrostomía (T0), y después de 4 (T1) y 12 (T3) semanas. El selenio fue valorado mediante GFAAS (Furnace Atomic Absorption Spectroscopy). Los enfermos consumieron alimentos de preparación doméstica. Los pacientes fueron estudiados como un grupo y después separados en dos grupos: cánceres de cabeza y cuello (CCC) y disfagia neurológica (DN). Resultados: 146 enfermos (89 hombres), entre 21‑95 años: CCC-56, DN-90. Valores normales de selenio en 79% (n = 115), albúmina baja: 77 enfermos, transferrina baja: 94, las dos proteínas bajas: 66, IMC bajo: 78. El selenio ha demostrado una evolución lenta en el 82% de los enfermos presentando selenio normal en T3. Las proteínas séricas incrementaron sus valores en T0-T3, la mayoría de los enfermos alcanzó niveles normales. La enfermedad subyacente, CCC o DN, se relacionó con las proteínas, pero no con el selenio. Conclusiones: el selenio sérico bajo es poco común antes de la gastrostomía; después de 4 y 12 semanas de nutrición enteral no tiene relación con las proteínas séricas ni con la enfermedad que causa la disfagia. La nutrición con alimentación de preparación doméstica es suficiente para prevenir o corregir la deficiencia de selenio de la mayoría de los enfermos.

  20. Serum Zn levels in dysphagic patients who underwent endoscopic gastrostomy for long term enteral nutrition.

    PubMed

    Santos, Carla Adriana; Fonseca, Jorge; Brito, José; Fernandes, Tânia; Gonçalves, Luísa; Sousa Guerreiro, António

    2014-02-01

    Objetivos: Pacientes con disfagia sometidos a Gastrostomía Endoscópica (PEG) presentan malnutrición calórico- proteica, mas poco se conoce acerca da malnutrición en micronutrientes. El objetivo del presente trabajo fue el estudio del zinc sérico en pacientes portadores de PEG y su relación con proteínas séricas, zinc de sangre total y enfermedades de base. Métodos: De los pacientes portadores de PEG se ha obtenido antes del procedimiento. La determinación del zinc del suero y total se ha obtenido por lo método Wavelength Dispersive X-ray Fluorescence Spectroscopy. Fueron consideradas la albumina y la transferrina. Se estudiaron pacientes como un todo y se dividieron en: cáncer de cabeza y cuello (CCC) y enfermedad neurológica (EN). Resultados: 32 pacientes (22 hombres), 43-88 años: CCC = 15, EN = 17. La mayoría (30/32) presento lo zinc en suero bajo. Solo dos, con lesión cerebral traumática, tenían valores normales de zinc. En la sangre total, 17/32 estaban dentro del rango normal. Sin diferencias entre los grupos CCC-EN. Sin asociación entre lo zinc sérico y la albumina o transferrina. Sin asociación entre lo zinc en suero y total. Conclusiones: los enfermos presentaran zinc sérico bajo no momento de la PEG, relacionado con el ayuno prolongado y no con la enfermedad subyacente. La reducción del zinc sérico no está relacionada con las proteínas. Lo zinc sérico fue más sensible para la identificación de reducción de la ingesta. Los grupos que se ocupan de enfermos con PEG deben incluir la determinación del zinc en la evaluación o incluir el suministro de zinc.

  1. ANTHROPOMETRY TO IDENTIFY HIGH VISCERAL FAT AREA IN POSTMENOPAUSAL WOMEN.

    PubMed

    Gondim Pitanga, Francisco José; Seara Pitanga, Cristiano Penas; Calçada Dias Gabriel, Ronaldo Eugénio; Cristina Beck, Carmem; Rodrigues Moreira, Maria Helena

    2015-12-01

    Introducción: la evaluación de la distribución de la grasa corporal por antropometría puede servir para identificar el exceso de grasa visceral. Este diagnóstico permitirá la aplicación de medidas específicas para prevenir y tratar el exceso de grasa visceral en mujeres posmenopáusicas. Objetivo: el objetivo de este estudio fue analizar diferentes indicadores antropométricos e identificar los mejores puntos de corte para discriminar sujetos con alta área de grasa visceral (AAGS) en mujeres posmenopáusicas. Métodos: estudio transversal con una muestra de 255 mujeres posmenopáusicas. Se construyeron diferentes curvas Receiver Operating Characteristic (ROC) y las áreas bajo ellas comparadas en términos del índice de conicidad (índice C), el índice de masa corporal (IMC), razón cintura-cadera (RCC), circunferencia de la cintura (CC), relación cintura-estatura (RCEst) y AAGS. La sensibilidad y la especificidad identificaron los mejores puntos de corte entre los diferentes indicadores antropométricos para discriminar sujetos con AAGS. El intervalo de confianza se fijó en 95%. Resultados: las zonas estadísticamente significativas bajo la curva ROC se encontraron para todos los indicadores antropométricos analizados. Fueron sugeridos los siguientes puntos de corte, con sus respectivas sensibilidades y especificidades, para discriminar sujetos con AAGS: índice C (1,19; 75,00%–74,77%); IMC (27,3 kg / m2; 81,08%–80,37%); RCC (0,98; 90,54%-83,18%); CC (85 cm; 85,14%-81,31%); y RCEst (0,55; 80,41%–80,37%). Conclusión: estos resultados demuestran que los indicadores antropométricos identifican bien a las mujeres postmenopáusicas con AAGS y pueden ser utilizados en lugar de los exámenes más sofisticados para detectar altos niveles de grasa visceral.

  2. [Not Available].

    PubMed

    Santaliestra-Pasías, Alba M; Bel-Serrat, Silvia; Moreno, Luis A; Bueno, Gloria

    2016-01-01

    Introducción: la elevada prevalencia de obesidad en niños es un problema de salud global y conlleva el desarrollo de comorbilidades asociadas, como hipertensión, dislipemia, inflamación crónica e hiperinsulinemia, que a su vez son reconocidos factores de riesgo cardiovascular. Algunos estudios han observado que el consumo de productos lácteos podría ejercer un papel protector sobre el desarrollo de enfermedades cardiovasculares; sin embargo, la evidencia científica es bastante limitada en niños y adolescentes.Objetivos: investigar la relación entre el consumo de productos lácteos y factores de riesgo cardiovascular en poblaciones jóvenes.Material y métodos: se ha revisado la literatura reciente, incluyendo adicionalmente datos procedentes del estudio HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence). Se incluyó una muestra de adolescentes (12,5-17,5 años) provenientes de 8 ciudades europeas.Resultados: datos estadounidenses muestran una disminución en la frecuencia de consumo de leche, así como en el tamaño de la porción consumida. En el estudio HELENA los productos lácteos fueron el grupo de alimentos que mejor identificó a los adolescentes con bajo riesgo cardiovascular. Además, un consumo elevado de leche y yogur, así como de bebidas a base de leche y yogur, se asoció con niveles más bajos de grasa corporal, menor riesgo cardiovascular y mayor condición física cardiorrespiratoria.Conclusiones: son necesarios más estudios para proporcionar evidencia y comprender mejor los mecanismos subyacentes de la asociación entre la ingesta de lácteos, especialmente el yogur, y la obesidad, la diabetes, y otros factores de riesgo cardiovascular. PMID:27571861

  3. How does parents' visual perception of their child's weight status affect their feeding style?

    PubMed

    Yilmaz, Resul; Erkorkmaz, Ünal; Ozcetin, Mustafa; Karaaslan, Erhan

    2013-01-01

    Introducción: El estilo de alimentación es uno de los factores prominentes que determina la ingesta de energía. Uno de los factores que influyen en el estilo de alimentación paterna es la percepción de los padres del estado de peso del niño. Objetivo: El propósito de este estudio fue evaluar la relación entre la percepción visual de la madre del estado de peso de su hijo y su estilo de alimentación. Método: Se realizó un estudio transversal con madres de 380 niños preescolares de 5 a 7 (6,14 años). Las puntuaciones de la percepción visual se midieron mediante unos dibujos y el estilo de alimentación materna se medió con el cuestionario validado “Parental Feeding Style Questionnaire”. Resultados: Las puntuaciones de las subescalas de las dimensiones de alimentación parental “alimentación emocional” y “animar a comer” eran bajas en niños con sobrepeso de acuerdo con la clasificación de la percepción visual. Las puntuaciones de las subescalas “alimentación emocional” y “control permisivo” eran estadísticamente distintas en los niños clasificados como correctamente percibidos e incorrectamente percibidos bajos por una mala percepción materna. Conclusión: Diversos estilos de alimentación se relacionaban con la percepción visual materna. El mejor abordaje para evitar la obesidad y el peso bajo podría estar en centrarse en conseguir una correcta percepción parental del estado de peso de sus hijos, mejorando así las habilidades paternas y conllevando la implantación de unos estilos de alimentación adecuados.

  4. [BEHAVIOR OF HEMOGLOBIN CONCENTRATION, HEMATOCRIT AND OXYGEN SATURATION IN COLOMBIAN UNIVERSITY POPULATION AT DIFFERENT ALTITUDES].

    PubMed

    Trompetero González, Andrea Catalina; Cristancho Mejía, Edgar; Benavides Pinzón, William Fernando; Serrato Roa, Mauricio; Landinez Macias, María Paula; Rojas, Joel

    2015-11-01

    Introducción: el desarrollo de la presente investigación se basa en el creciente interés por comprender las adaptaciones a la hipoxia crónica, principalmente en el rango altitudinal denominado de alturas intermedias (1.500- 3.000 m.s.n.m), con la necesidad de establecer parámetros de normalidad en las variables [Hb], Hct y SO2 con fines diagnósticos y de caracterización de la población. Objetivos: analizar el comportamiento de la [Hb], el Hct y la SaO2 a diferentes alturas intermedias (970 m.s.n.m, 1.520 m.s.n.m, 1.728 m.s.n.m, 1.923 m.s.n.m, 2.180 m.s.n.m y 2.600 m.s.n.m) con el fin de aportar conocimiento sobre la fisiología de la altura y al campo clínico para apoyar el diagnóstico de anemia. Métodos: sujetos clínicamente sanos, con nivel bajo de actividad física y reporte de consumo de alimentos con contenido de hierro. Total de 264 participantes de ambos géneros entre 18 y 30 años. Las muestras se obtuvieron de sangre de la vena antecubital y del lóbulo de la oreja y fueron analizadas en un radiómetro. Se realizó un análisis estadístico no paramétrico. Resultados: con el incremento de la altitud los valores de [Hb] y Hct se incrementaron, mientras la SO2 descendió. Los hombres presentaron valores más altos que las mujeres en [Hb] y Hct, relacionado con valores más bajo de SO2 que las mujeres. Discusión: no se evidenció un umbral de las variables, quizás por la pequeña distancia entre las alturas. Los valores reportados fueron similares pero no iguales a otros estudios, lo que podría deberse a la diversidad genética entre poblaciones. Conclusiones: este estudio permite obtener los primeros valores de caracterización de la población estudiada. Todas las alturas estuvieron por encima del punto de corte para el diagnóstico de anemia ([Hb] 12 g/dl).

  5. [In Process Citation].

    PubMed

    Martín Álvarez, Estefanía; Jiménez Cabanillas, María Victoria; Peña Caballero, Manuela; Serrano López, Laura; Kajarabille, Naroa; Díaz Castro, Javier; Ochoa Herrera, Julio José; Maldonado Lozano, José

    2016-03-25

    Introducción: el recién nacido prematuro de muy bajo peso (RNMBP) es inmunológicamente inmaduro y además presenta una alteración de las barreras naturales de defensa. Objetivo: evaluar los efectos que pueda tener la administración de calostro orofaríngeo, administrado durante los primeros 15 días posnatales, sobre los niveles de inmunoglobulina A (IgA) sérica en recién nacidos prematuros de muy bajo peso durante el primer mes de vida. Material y métodos: se desarrolló un estudio de intervención no aleatorizado con grupo control, en el que se incluyeron 38 recién nacidos con ≤ 32 + 6 semanas de gestación y/o menores de 1.500 g de peso. Los sujetos recibieron 0,2 ml de calostro de su madre cada 4 h, iniciándose el procedimiento en las primeras 24 h de vida hasta el 15.o día postnatal. Se midieron los niveles de IgA en la sangre al nacimiento, 3. er , 15.o y 30.o días de vida. Se registraron datos perinatales al nacimiento y durante el periodo de seguimiento. Resultados: IgA sérica aumentó de forma estadísticamente significativa en el grupo de intervención (M1 15,84 μg/ml, M2 20,07 μg/ml, M3 23,65 μg/ml, M4 30,34 μg/ml, p 0,001) y en el grupo control (M1 12,48 μg/ml, M2 16,48 μg/ml, p 0,018; M3 19,41 μg/ml, M4 22,48 μg/ml, p 0,001). Al mes de vida, los niveles de IgA sérica fueron significativamente mayores en el grupo de intervención que en el grupo control (p 0,026). Conclusiones: este estudio sugiere que la administración de calostro orofarínge.

  6. GASTRIC CANCER AND ASSOCIATED FACTORS IN HOSPITALIZED PATIENTS.

    PubMed

    Galvão de Azevedo, Ioná; Leal Muniz Carneiro, Izabel Cristina; Oliveira Tomiya, Marília Tokiko; Pessoa de Araújo Burgos, Maria Goretti

    2015-07-01

    Introducción: a pesar de la disminución de la incidencia y la mortalidad, el cáncer gástrico sigue siendo el cuarto tumor más frecuente y la segunda causa de muerte por cáncer en el mundo. Objetivos: analizar los factores asociados con el cáncer gástrico en pacientes hospitalizados. Método: estudio de corte serie de casos, realizado en hospitales de Recife. Los datos fueron obtenidos a partir de cuestionarios adaptados de un modelo previamente validado, que contenían los problemas socioeconómicos, los hábitos alimentarios, el estilo de vida, los antecedentes familiares de cáncer, la infección por H. pylori y los datos antropométricos. Resultados: de los 33 pacientes, tuvieron un ligero predominio las mujeres con edades ≥ 60 años, de zonas rurales, con bajos niveles de educación e ingresos. De acuerdo con el IMC, el 57,6% fueron normales y el 69,7% en riesgo nutricional cuando se utiliza% PP. Se encontró que el 42,4% no se sometió a examen para H. pylori, el 48,5% tenían una predisposición genética, el 75,8% eran sedentarios, el 60,6% eran fumadores y ex fumadores, el 51,5% eran adictos al alcohol y el 36,4% tenían sobrepeso. Hubo consumo frecuente de alimentos salados, alimentos fritos, baja ingesta de frutas, alimentos que contienen nitratos/ nitritos, así como una inadecuada conservación de los alimentos. Conclusión: el bajo nivel socioeconómico, la inactividad física y los hábitos alimentarios inadecuados fueron factores predominantes para el cáncer gástrico en el grupo analizado.

  7. Review of complementary feeding practices in Mexican children.

    PubMed

    Pantoja-Mendoza, Itzayana Y; Meléndez, Guillermo; Guevara-Cruz, Martha; Serralde-Zúñiga, Aurora E

    2014-10-19

    Antecedentes: El inicio de la alimentación complementaria temprana coincide con un aumento significativo en la prevalencia de sobrepeso y obesidad especialmente en los niños, lo cual se debe entre otras causas a los cambios en los patrones de alimentación que se han experimentado. El objetivo del estudio fue describir las prácticas de alimentación complementaria en niños mexicanos. Métodos: Se realizó una búsqueda de los estudios que evaluaron las prácticas alimentarias en menores de 2 años en México en Medline, Lilacs y de forma manual con los siguientes términos: alimentación complementaria, alimentación suplementaria, México, ablactación y destete. Se recabó la edad de inicio de la alimentación complementaria, tipo de alimento consumido, frecuencia de consumo de los alimentos y motivo por el que iniciaban la alimentación complementaria. Se realizó un análisis cualitativo de la información recolectada y los datos en las gráficas son mostrados como proporciones. Resultados: Se incluyeron 7 estudios que mostraron que los niños inician la alimentación complementaria antes de los 6 meses predominantemente con frutas, aunque también consumieron jugos industrializados, refrescos y frituras. El consumo de estos productos aumenta con el crecimiento de los niños, aunado a un bajo consumo de alimentos con proteína de alto valor biológico, especialmente las carnes rojas. Conclusiones: Los resultados de los estudios incluidos mostraron que los menores reciben alimentos con alta densidad energética, mientras que es bajo el consumo de aquellos que aportan proteína animal y hierro en particular, lo que puede contribuir a problemas de salud como sobrepeso, obesidad, desnutrición y anemia.

  8. [Body profile and physical and cognitive function by age in ambulatory elderly women from the city of Córdoba].

    PubMed

    Asaduroglu, Ana V; Tablada, M; Cosiansi Bai, J; Carrillo, M; Canale, M; Gallerano, R

    2015-01-01

    El envejecimiento produce cambios corporales como redistribución de la grasa y pérdida de la masa y fuerza muscular, predisponiendo a fragilidad, deterioro funcional y discapacidad. Objetivo: Analizar la relación entre perfil corporal y función física y cognitiva según edad en mujeres mayores de la ciudad de Córdoba. Material y Métodos: Se valoraron 178 Mujeres Mayores (MM) sanas ambulatorias ≥60 años que asisten a Centros de Jubilados y Hogares de Día de Córdoba capital. Se evaluó Perfil Corporal a partir de: índice de masa muscular esquelética (IMME), adiposidad corporal relativa (ACR) -absorciometría dual de rayos X- y fuerza muscular (FM) –dinamometría-. Categorías: Normal/(N) Sarcopenia/(SP), Obesidad/(OB), Obesidad Sarcopénica/(OB/SP); Función Física: con/sin limitación física (LF); y Función Cognitiva: con/sin deterioro cognitivo (DC). Instrumentos: Densitómetro Lunar Prodigy y dinamómetro Smedley, Escalas de Lawton y Brody y Minimental Examination de Folstein. Resultados: La OB/SP predominó y se incrementó con la edad; contrario a la OB. La mayoría de las MM no presentó LF ni DC. Sólo 2,25% tuvo IMME bajo y 48,3% dinapemia. El 76,97% tenía ACR elevada. Las SP –obesas o no- presentaron mayor LF y DC. La frecuencia de DC duplicó a la de LF (15,17% versus 6,74%). Se hallaron correlaciones negativas y asociaciones significativas entre edad y FM (r= -0,279; p=0,0001), FF (r= -0,164; p=0,0283) y FC (r= -0,028; p=0,0002). Conclusiones: En este grupo de MM sanas la dinapenia fue responsable de la SP observada, no el IMME bajo. Las ancianas SP tuvieron mayor LF y DC, y aumentaron con la edad.

  9. Design of quality indicators for oral nutritional therapy.

    PubMed

    Gimenez Verotti, Cristiane Comeron; de Miranda Torrinhas, Raquel Susana Matos; Pires Corona, Ligiana; Waitzberg, Dan Linetzky

    2015-06-01

    Objetivo: los indicadores de calidad en la terapia nutricional han sido propuestos como herramientas útiles para mejorar la terapia nutricional (TN). Este estudio pretende diseñar indicadores de calidad de terapia nutricional oral (ICTNO) factibles en el control de calidad de TN oral. Métodos: el diseño de ICTNO fue realizado por una comisión de nutrición clínica compuesta por brasileños expertos en TN del International Life Science Institute (ILSI). Más tarde, la aprobación de estos ICTNO fue valorada con análisis psicométricos recogiendo las opiniones de otros brasileños dedicados independientemente a la TN (n = 40) vía SurveyMonkey (encuesta por internet). Esta consistió en cuatro atributos valorando cada ICTNO (simplicidad, utilidad, objetividad y bajo precio) seguida de una escala Likert con cinco puntos. Resultados: los expertos en TN de ILSI proporcionaron el diseño de 12 QIONT, que fueron todos consistentemente (Alfa de Cronbach = 0,84) clasificados como válidos por expertos independientes en NT. Por orden de relevancia, los nuevos ICTNO valoraron: la frecuencia de screening nutricional, la prescripción de suplementos de nutrición oral para pacientes desnutridos que ya reciben dieta oral, la prescripción de suplementos de nutrición oral para pacientes con bajo riesgo nutricional que ya reciben dieta oral, el consejo nutricional, la adhesión al suplemento nutricional oral, los pacientes hospitalizados con dieta oral insuficiente y prescripción de suplementos nutricionales orales, los pacientes de UCI con dieta oral insuficiente y prescripción de suplementos nutricionales orales, el consejo de nutrición oral en pacientes de UCI, el consejo de nutrición oral en pacientes en planta, la intolerancia al volumen de suplemento oral debido a dosificación inadecuada, la intolerancia al sabor del suplemento oral y la intolerancia al volumen de suplemento oral. Conclusión: según la opinión experta, 12 potenciales y factibles nuevos ICTNO

  10. [Systolic pressure, abdominal obesity and body fat, metabolic syndrome predictors in Spanish preschoolers].

    PubMed

    Gutiérrez Hervás, Ana Isabel; Rizo Baeza, María Mercedes; Martínez Amorós, Natalia; Cortés Castell, Ernesto

    2015-05-01

    Se plantea como objetivo determinar la presencia de predictores de síndrome metabólico en niños de 2 a 7 años en relación a su estado nutricional. Método: Estudio descriptivo con análisis cuantitativo en 260 niños de 2-7 años (135 niñas y 125 niños), 66% del total censados. Se midieron parámetros antropométricos y tensión arterial y se calcularon IMC, grasa corporal según Hoffman e índice cintura-talla (ICT). Se realizaron subgrupos con Z-Score del IMC según edad y sexo (bajo peso, normopeso, sobrepeso y obesidad), según grasa corporal (normal y con exceso), ICT (normal y obesidad abdominal) y tensión sistólica (normotensos e hipertensos según edad y sexo). Se utilizó como variable principal la clasificación según Z-Score del IMC. Resultados: La prevalencia combinada de sobrepeso y obesidad fue del 27%, sin diferencias por sexo. El estado nutricional relacionó significativamente con tensión arterial, grasa corporal e índice cintura-talla. Mayor porcentaje de obesos con tensión arterial sistólica alta que de normonutridos (OR=4.1; IC95% 1.7-9.8; p.

  11. NUTRITIONAL STATUS, DIET AND NON-ALCOHOLIC FATTY LIVER DISEASE IN ELDERS.

    PubMed

    de Melo Portela, Clarissa Lima; de Carvalho Sampaio, Helena Alves; Pereira de Melo, Maria Luísa; Ferreira Carioca, Antonio Augusto; Maia Pinto, Francisco José; Machado Arruda, Soraia Pinheiro

    2015-11-01

    Objetivo: evaluar las interrelaciones entre enfermedad grasa no alcohólica del hígado (HGNA) y factores dietéticos en una población de ancianos hipertensos. Métodos: 229 pacientes ancianos hipertensos fueron evaluados desde junio a diciembre del 2009. Todos los pacientes que aceptaron participar en el estudio firmaron un consentimiento libre e informado. Fueron realizadas evaluaciones antropométricas y de composición corporal. El diagnóstico de HGNA fue determinado por el American Guidelines. El consumo alimenticio regular fue estimado a través de una encuesta alimentaria de recordatorio de 24 horas. Resultados: el exceso de peso, ponderado por el índice de masa corporal y el exceso de grasa abdominal, fueron asociados con HGNA (p < 0,001). Un perfil inverso fue encontrado con las variables dietéticas. Conclusión: el grupo estudiado presentó una situación de riesgo para la salud, considerando los marcadores del estado nutricional. La dieta regular pareció ser inadecuada, mostrando exceso de sodio bajo consumo de fibras y vegetales.

  12. Are poor physical fitness and obesity two features of the adolescent with Down syndrome?

    PubMed

    Izquierdo-Gomez, Rocío; Martínez-Gómez, David; Tejero-Gonzalez, Carlos María; Cabanas-Sánchez, Verónica; Ruiz Ruiz, Jonathan; Veiga, Óscar L

    2013-01-01

    Introducción: La obesidad es considerada una característica de los jóvenes con SD, sin embargo se desconoce si la “baja condición física” también lo es. Objetivo: Comparar los niveles de obesidad y condición física en adolescentes con y sin SD. Métodos: Participaron 17 adolescentes (5 niñas) con SD de 12 a 18 años y un grupo control de 94 (45 niñas) adolescentes sin SD de 12-16 años de edad. La batería de condición física ALPHA relacionada con la salud para niños y adolescentes fue seleccionada para evaluar la obesidad y la condición física en ambos grupos. Resultados: No se encontraron diferencias en los niveles de obesidad entre grupos (P > 0,27). Los adolescentes con SD tuvieron niveles más bajos de condición física en todos los test en comparación con los adolescentes sin SD (P < 0,001). Conclusión: Los adolescentes con SD tienen niveles similares de obesidad y menores de condición física que sus compañeros sin SD.

  13. [Thrombolysis in left mechanical prosthetic heart valve obstruction by thrombus. Following and results].

    PubMed

    Valencia-Sánchez, Jesús Salvador; Arriaga-Nava, Roberto

    2014-01-01

    INTRODUCCIÓN: la obstrucción de la válvula mecánica cardiaca izquierda por trombo es una complicación grave. Los factores relacionados con la mortalidad son clase funcional, tipo de prótesis valvular y urgencia de la cirugía. La trombólisis representa una opción terapéutica a la cirugía cardiaca. El objetivo de esta investigación fue analizar el papel de la trombólisis en el manejo de la válvula mecánica cardiaca izquierda obstruida por trombo. MÉTODOS: se estudiaron 22 casos consecutivos sometidos a trombólisis en el Hospital de Cardiología del Centro Médico Nacional Siglo XXI, bajo dos diferentes circunstancias: con edema agudo pulmonar y estado de choque en clase funcional IV y con clases funcionales I y II. Se realizó monitoreo clínico, ecocardiográfico y fluoroscopia.

  14. Geologic and tectonic setting of Deseado Massif epithermal deposits, Argentina, based on El Dorado-Monserrat

    NASA Astrophysics Data System (ADS)

    Echavarría, Leandro E.; Schalamuk, Isidoro B.; Etcheverry, Ricardo O.

    2005-09-01

    Middle-Late Jurassic bimodal volcanism, typical of a retroarc setting, developed during widespread extensional tectonism within the Deseado Massif, southern Argentina. This geologic environment led to the formation of numerous low-sulfidation epithermal deposits that are spatially and temporally related to the volcanic activity. The lack of significant high-sulfidation epithermal deposits may be because the tectonic and volcanic settings do not favor the formation of these types of deposits. El Dorado-Monserrat is a low-sulfidation epithermal prospect located near the southern boundary of the Deseado Massif. Mineralization is genetically linked to the Late Jurassic Chon Aike Formation and hosted by volcanic rocks of the middle Late Jurassic Bajo Pobre Formation. Two different mineralization areas have been identified. The Monserrat area is the most important, with veins hosted in a north-striking, left-lateral shear zone. The average thickness is 0.85 m, and the average metal content is 6.2 ppm gold and 153 ppm silver. The El Dorado area has discontinuous echelon veins within a right-lateral shear zone with low gold and silver grades. Hydrothermal alteration of the host rocks includes an inner zone of quartz-adularia and illite alteration and an outer zone of propylitic alteration. The main gangue mineral is quartz, which formed in successive pulses, plus adularia, pyrite, hematite, magnetite, and barite. Precious metals occur as zoned electrum. Ore mineral precipitation took place between 200 and 280 °C from low salinity fluids due to boiling.

  15. [Kidney function in marginalized population: a pilot study].

    PubMed

    Medina-Escobedo, Martha; Sansores-España, Delia; Villanueva-Jorge, Salha

    2014-01-01

    INTRODUCCIÓN: la enfermedad renal crónica (ERC) es un problema de salud pública. A nivel mundial, más del 6 % de la población la padece. Tener un nivel educativo y socioeconómico bajo, así como acceso limitado a los servicios médicos incrementan la probabilidad de daño renal. Los objetivos de esta investigación fueron evaluar y clasificar la función renal de la población marginada de Yucatán. MÉTODOS: estudio observacional, prospectivo, transversal, descriptivo, en una muestra no probabilística consecutiva, en adultos del área de consulta externa de un hospital general. Se incluyeron sujetos marginados (confirmado por encuesta socioeconómica), sin edema, embarazo ni diabetes mellitus. Se realizaron pruebas de función renal; se calculó filtrado glomerular y se estadificaron las enfermedades de los pacientes, según guías KDOQI. Se determinó peso, talla, índice de masa corporal (IMC), porcentaje de grasa y presión arterial. Se compararon los resultados entre grupos por sexo y por población rural y urbana.

  16. [Programme review of somatropin deficit in pediatrics at the Hospital Universitario Virgen del Rocío].

    PubMed

    Lavaredas, A; de la Puerta, R; Álvarez del Vayo, C

    2013-01-01

    Objetivo: Elaborar una revisión del programa de déficit de somatropina aplicado en pediatría en el Hospital Universitario Virgen del Rocío, utilizando dos grupos de pacientes, los diagnosticados con déficit de esta hormona y los nacidos pequeños para edad gestacional, con la intención de evaluar su efectividad en el primer año de tratamiento. Método: Realización de un estudio retrospectivo de la cohorte de pacientes en tratamiento con la hormona del crecimiento bajo los diagnósticos mencionados, con metodología observacional y transversal, a los cuales se aplicó un análisis estadístico con el programa Statistical Package for Social Sciences®. Resultados: Tras inicio del tratamiento la velocidad de crecimiento y la talla aumentaron y la edad ósea se aproximó a la edad cronológica. En los dos grupos tratados, en el primer año de tratamiento fueron los pacientes del sexo femenino con edad comprendida entre los 0 a 12 años con déficit de la hormona del crecimiento que respondieron mejor a la terapéutica establecida. Conclusiones: Pudimos observar que el tratamiento instituido se presentó altamente efectivo en ambos grupos de pacientes, permitiendo obtener un aumento favorable de estatura.

  17. Organic acid contents in onion cultivars (Allium cepa L.).

    PubMed

    Rodríguez Galdón, Beatriz; Tascón Rodríguez, Catalina; Rodríguez Rodríguez, Elena; Díaz Romero, Carlos

    2008-08-13

    The following organic acids (glutamic, oxalic, pyruvic, malic, tartaric, citric, and fumaric), pungency, Brix degree, acidity, and pH were determined in onion cultivars (Texas, Guayonje, San Juan de la Rambla, Carrizal Alto, Carrizal Bajo, and Masca) harvested in the same agroclimatic conditions. Glutamic acid was the most abundant organic acid (325 +/- 133 mg/100 g) followed by citric acid (48.5 +/- 24.1 mg/100 g) and malic acid (43.6 +/- 10.4 mg/100 g). There were significant differences between the onion cultivars in the mean concentrations of all of the analyzed parameters. The San Juan de la Rambla and Masca cultivars presented, in general, higher concentrations of the organic acids than the other cultivars. Significant differences in most of the analyzed parameters were observed between the two seed origins for the Masca and San Juan de la Rambla cultivars. The onion samples tended to be classified according to the cultivar and, in the case of San Juan de la Rambla cultivar, according to the precedence of the seeds after applying discriminant analysis. PMID:18616262

  18. [Low grade fibromixoid sarcoma: a purpose of 3 cases and review of the bibliography].

    PubMed

    Citores-Pascual, Miguel Angel; Tinoco-Carrasco, Claudia; Arenal-Vera, Juan José; Benito-Fernández, César; Torres-Nieto, María de Los Ángeles; Zamora-Martínez, Tomás

    2013-01-01

    Antecedentes: el sarcoma fibromixoide de bajo grado o tumor de Evans es una variedad de sarcoma de partes blandas que representa el 1% de todos los tumores malignos. Más frecuente en extremidades y tronco (50%), presentamos tres nuevos casos de localización retroperitoneal. Se revisan sus características y se realiza actualización bibliográfica. Casos clínicos: en su localización retroperitoneal destaca lo inespecífico de su sintomatología clínica, se manifiesta en función de su crecimiento y tamaño, como una tumoración abdominal, habitualmente indolora, o por la compresión y/o invasión de estructuras próximas. Los casos presentados se manifestaron, por la presencia de tumoración abdominal, sin otra sintomatología; a pesar de infiltrar a otros órganos. Conclusiones: el diagnóstico preoperatorio es difícil, y debe tenerse la presunción clínica para solicitar el estudio histológico, con tipificación inmuno-histo-química para su dentificación precisa.

  19. [Burnout and quality of life in medical residents].

    PubMed

    Prieto-Miranda, Sergio Emilio; Rodríguez-Gallardo, Gisela Bethsabé; Jiménez-Bernardino, Carlos Alberto; Guerrero-Quintero, Laura Guadalupe

    2013-01-01

    Introducción: el burnout y la calidad de vida son fenómenos poco estudiados en estudiantes de posgrado y sus efectos se desconocen. Métodos: estudio descriptivo longitudinal. Se incluyeron residentes que iniciaron su primer año de posgrado en marzo de 2010. Se aplicó, a su ingreso, a los 6 y 12 meses, la versión española del cuestionario PEC VEC de perfil de calidad de vida validado al español y el inventario de burnout de Maslach específico para médicos. Para las variables nominales se utilizó ?2 y para variables numéricas Anova. Resultados: se incluyeron 45 residentes. La edad promedio fue de 26.9 ± 2.93; 18 (40 %) fueron del sexo femenino y 27 (60 %) del masculino. En la encuesta PEC VEC se encontró un descenso significativo en cuatro de las seis escalas valoradas en las tres mediciones realizadas. En el cuestionario de burnout se encontraron niveles altos de agotamiento emocional en las tres pruebas, bajo grado de despersonalización, y logros personales al ingreso, elevándolos a los 6 y 12 meses. La especialidad más afectada fue medicina interna. Conclusiones: hay presencia de burnout y deterioro de calidad de vida en médicos residentes que estudian posgrado y se mantiene durante el primer año de residencia.

  20. [Functional connectivity and complex networks in focal epilepsy. Pathophysiology and therapeutic implications].

    PubMed

    Pastor, Jesús; Sola, Rafael G; Vega-Zelaya, Lorena; Garnes, Óscar; Ortega, Guillermo J

    2014-05-01

    Introduccion. El modelo tradicional de cirugia de la epilepsia focal consiste en la localizacion y reseccion de la zona epileptogena. Sin embargo, una minoria significativa de pacientes epilepticos sigue teniendo crisis tras la reseccion, lo que muestra el nivel de conocimiento incompleto que actualmente se tiene sobre esta materia. Objetivo. Introducir algunos conceptos de conectividad funcional y redes complejas y su aplicacion al estudio de registros neurofisiologicos de pacientes con epilepsia focal farmacorresistente, principalmente del lobulo temporal. Desarrollo. Con el objeto de entender con plenitud los nuevos desarrollos en el area de redes complejas y sus aplicaciones al estudio de la epilepsia, se revisaran los conceptos fundamentales de la metodologia de redes complejas, sincronizacion y conectividad funcional. Asimismo, se revisaran algunos de los trabajos mas recientes en los que se analizan registros neurofisiologicos y resonancias funcionales de pacientes con epilepsia focal bajo esta nueva perspectiva. Conclusiones. Una vision mas amplia en la perspectiva para el entendimiento de la epilepsia focal, como la tratada en este trabajo, permitira tambien plantear nuevas alternativas al tratamiento quirurgico de la epilepsia focal, tanto con el desarrollo de nuevos metodos no invasivos como con la mejora y optimizacion de algunos de los metodos invasivos ya existentes.

  1. [Pharmacotherapy for tinnitus: much ado about nothing].

    PubMed

    Espinosa-Sánchez, Juan M; Heitzmann-Hernández, Teresa; López-Escámez, José A

    2014-08-16

    Introduccion. El 5-15% de la poblacion general presenta acufenos cronicos, que afectan de manera grave a la calidad de vida del 1% de los casos. El tratamiento farmacologico es una de las opciones terapeuticas en el abordaje de pacientes con acufenos, aunque su eficacia es controvertida. Objetivo. Evaluar el nivel de evidencia que sustenta el uso de diferentes farmacos para reducir la intensidad de los acufenos. Desarrollo. Se han revisado varios grupos farmacologicos incluyendo anestesicos, antiepilepticos, antidepresivos, antihistaminicos, benzodiacepinas, diureticos, corticoides y otras sustancias. La lidocaina intravenosa parece ser eficaz aunque la breve duracion de su efecto y la aparicion de reacciones adversas han llevado a descartarla. La carbamacepina y la gabapentina no han mostrado eficacia frente a placebo, si bien podrian ser eficaces en algunos pacientes con compresion neurovascular o mioclonias. Los antidepresivos triciclicos no son mas eficaces que el placebo aunque pueden mejorar una depresion coexistente. La evidencia es insuficiente para evaluar la eficacia de los inhibidores selectivos de la recaptacion de serotonina y las benzodiacepinas. El acamprosato podria reducir la intensidad de los acufenos, aunque el nivel de evidencia es bajo. No disponemos de resultados consistentes para el tratamiento de los acufenos de la enfermedad de Meniere empleando gentamicina intratimpanica o corticoides. Conclusiones. La utilizacion de medicamentos para reducir la intensidad de los acufenos no esta bien apoyada por ensayos clinicos controlados, aleatorizados y prospectivos. Algunos farmacos son eficaces en algunos estudios, pero la evidencia es limitada. Se necesitan ensayos clinicos aleatorizados mas amplios.

  2. Newtonian Version of the Variable Mass Theory of Gravity

    NASA Astrophysics Data System (ADS)

    Carvalho, J. C.; Lima, J. A. S.

    1990-11-01

    RESUMEN. Se presenta una versi6n Newtoniana de los modelos cosmol6gicos espacialmente e isotr6picos con masa variable. La influencia de la variaci6n de masa en la evoluci6n de la funci6n de escala est establecida para el caso de un Universo lieno de polvo bajo Ia suposici6n de que esta variaci6n es un efecto estrictamente cosmol6jico. Se muestra que el hiperb6lico, parab6lico 0 el#ptico dcl movimiento de puede ser modificado a lo larjo de la expansi6n. ABSTRACT. This paper presents a Newtonian version of the spatially homojeneous and isotropic cosmolojical models with variable mass. The influence of the mass variation on the evolution of the scale function is established for the case of a dust-filled Universe under the assumption that this variation is a strict cosmolojical effect. It is shown that the hyperbolic, parabolic or elliptic character of the fluid motion can be modified alonj the expansion. Keq : COSMOLOGY

  3. Remote Sensing in Archaeology: Visible Temporal Change of Archaeological Features of the Peten, Guatemala

    NASA Technical Reports Server (NTRS)

    Lowry, James D., Jr.

    1999-01-01

    The purpose of this archaeological research was two-fold; the location of Mayan sites and features in order to learn more of this cultural group, and the (cultural) preservation of these sites and features for the future using Landsat Thematic Mapper (TM) images. Because the rainy season, traditionally at least, lasts about six months (about June to December), the time of year the image is acquired plays an important role in spectral reflectance. Images from 1986, 1995, and 1997 were selected because it was felt they would provide the best opportunity for success in layering different bands from different years together to attempt to see features not completely visible in any one year. False-color composites were created including bands 3, 4, and 5 using a mixture of years and bands. One particular combination that yielded tremendously interesting results included band 5 from 1997, band 4 from 1995, and band 3 from 1986. A number of straight linear features (probably Mayan causeways) run through the bajos that Dr. Sever believes are features previously undiscovered. At this point, early indications are that this will be a successful method for locating "new" Mayan archaeological features in the Peten.

  4. Fotometría superficial de la galaxia irregular NGC 1427A

    NASA Astrophysics Data System (ADS)

    Cellone, S. A.; Forte, J. C.

    Se presenta fotometría superficial multicolor de la galaxia irregular NGC 1427A. Esta galaxia, un miembro del Cúmulo de Fornax que no ha sido estudiado previamente, muestra una morfología muy particular: una distribución estelar subyacente de bajo brillo superficial (LSB) con varias manchas brillantes dispuestas en una estructura anular deformada. Por sus colores muy azules se infiere que estas son zonas de formación estelar reciente. Al norte del cuerpo principal de la galaxia, y conectado con éste mediante filamentos LSB, hay un objeto de isofotas aproximadamente circulares. Este objeto tiene en sí mismo algunas zonas brillantes, pero su población estelar subyacente es significativamente más azul que la del cuerpo principal de la galaxia. Esto indica que ambos objetos han tenido distintas historias evolutivas. Estructuralmente, el objeto del norte es muy similar a algunas de las galaxias elípticas enanas más débiles que pueblan el Cúmulo de Fornax. Se discute la posible relación entre este objeto y la galaxia en si.

  5. [Frequency of eating away-from-home and quality of dietary carbohydrate and fat intake in the SUN Project].

    PubMed

    Villacis, Cecilia; Zazpe, Itziar; Santiago, Susana; De la Fuente-Arrillaga, Carmen; Bes-Rastrollo, Maira; Martínez-González, Miguel Angel

    2014-10-03

    Objetivo: Investigar la asociación entre la frecuencia de comidas fuera de casa (CFC) con a) la calidad de hidratos de carbono y b) la calidad de grasas. Materiales y métodos: Se evaluaron 19.371 participantes de la cohorte SUN que completaron un cuestionario basal de frecuencia de consumo de alimentos previamente validado. Se utilizaron los índices de calidad de hidratos de carbono (ICHC) en una escala de 4 a 20 y de grasas (ICG) en una escala de 0,62 a 5,92. En ambos casos, a mayor puntuación mayor calidad. Se utilizó la regresión lineal múltiple para determinar la asociación entre la frecuencia de CFC (4 categorías) y la puntuación de ambos índices, y la regresión logística para medir la asociación entre la frecuencia de CFC y un bajo ICHC o ICG (

  6. Evaluation of a PCR-RFLP-ITS2 assay for discrimination of Anopheles species in northern and western Colombia.

    PubMed

    Cienfuegos, Astrid V; Rosero, Doris A; Naranjo, Nelson; Luckhart, Shirley; Conn, Jan E; Correa, Margarita M

    2011-05-01

    Anopheles mosquitoes are routinely identified using morphological characters of the female that often lead to misidentification due to interspecies similarity and intraspecies variability. The aim of this work was to evaluate the applicability of a previously developed PCR-RFLP-ITS2 assay for accurate discrimination of anophelines in twelve localities spanning three Colombian malaria epidemiological regions: Atlantic Coast, Pacific Coast, and Uraba-Bajo Cauca-Alto Sinu region. The evaluation of the stability of the PCR-RFLP patterns is required since variability of the ITS2 has been documented and may produce discrepancies in the patterns previously reported. The assay was used to evaluate species assignation of 939 mosquitoes identified by morphology. Strong agreement between the morphological and molecular identification was found for species Anopheles albimanus, Anopheles aquasalis, Anopheles darlingi and Anopheles triannulatus s.l. (p≥0.05, kappa=1). However, disagreement was found for species Anopheles nuneztovari s.l., Anopheles neomaculipalpus, Anopheles apicimacula and Anopheles punctimacula (p≤0.05; kappa ranging from 0.33 to 0.80). The ITS2-PCR-RFLP assay proved valuable for discriminating anopheline species of northern and western Colombia, especially those with overlapping morphology in the Oswaldoi Group. PMID:21345325

  7. [Enviromental factors related to depressive disorders].

    PubMed

    Hernández-Benítez, Catalina Teresa; García-Rodríguez, Alfonso; Leal-Ugarte, Evelia; Peralta-Leal, Valeria; Durán-González, Jorge

    2014-01-01

    Introducción: debido a su alta prevalencia, la depresión mayor, episodio único (DMEU); la depresión mayor recurrente (DMR); y la distimia son consideradas un problema importante de salud pública. El objetivo de este estudio fue identificar y relacionar los factores ambientales en pacientes con DMEU, DMR y distimia. Métodos: 121 pacientes procedentes del Hospital General de Subzona del Instituto Mexicano del Seguro Social (IMSS) de San Andrés Tuxtla, Veracruz, fueron cuestionados mediante una historia clínica con las variables de riesgo. Resultados: 16 pacientes presentaron DMEU, 72 DMR y 33 distimia. En todos prevaleció el sexo femenino. Los trastornos depresivos se observaron con más frecuencia en personas de más de 40 años, casadas, con un nivel de estudios medio o bajo, provenientes de una familia disfuncional, víctimas de violencia familiar, además de ser hijos intermedios. Las comorbilidades que se presentaron fueron trastornos gastrointestinales, obesidad e hipertensión arterial. Conclusión: los principales factores de riesgo que se identificaron para desarrollar trastornos depresivos fueron: ser mujer, tener más de 40 años de edad y estar casada. Las diferencias obtenidas en este estudio respecto a otros probablemente se deban al tamaño de la muestra, los criterios de selección y el origen de la etnia.

  8. [Anti-inflammatory activity of olive seed polyphenolic extract in the THP1-XBLUE-CD14 human monocytes cell line].

    PubMed

    Cortés Castell, Ernesto; Veciana Galindo, C; Torro Montell, L; Sirvent Segura, E; Rizo Baeza, M M; Gil Guillén, V

    2014-07-01

    El objetivo de este trabajo es evaluar la actividad antiinflamatoria de un extracto de naturaleza polifenólica de huesos de oliva. MATERIAL Y MÉTODOS: Se incubó la línea celular THP1- XBlue-CD14 (invivogen), 80.000 células/pocillo, provocando inflamación (activación de NF-kb) mediante 0.1 μg/ml LPS (lipopolisacárido de E. coli) durante 24 horas. Se evaluó la presencia del extracto (10 y 50 mg/l, concentraciones bioseguras) durante 2 horas a 37 ºC, previa (efecto preventivo) y posterior a la activación proinflamatoria (efecto terapéutico) y se cuantificó colorimétricamente la actividad de fosfatasa alcalina, que se expresa bajo el control del promotor del factor transcripcional de NF-kb. Se evalúa el % actividad de NF-kb en efecto preventivo y terapéutico respecto a cultivos control de células con LPS y sin extracto añadido, que se consideran 100% de NF-kb.

  9. [Neuroethics (I): moral pathways in normal brain].

    PubMed

    Álvaro-González, Luis C

    2014-03-01

    Introduccion. La moralidad es el conjunto de normas y valores que guian la conducta. Se mantienen en muy diferentes culturas. Permiten alcanzar logros sociales que solo se entienden bajo el desarrollo moral, con un sentido de justicia que penetra toda accion humana. Las funciones morales, fruto del desarrollo evolutivo, asientan en circuitos neuronales propios. Objetivo. Describir su aparicion, puesta en marcha y mecanismos operativos en el cerebro normal. Desarrollo. Las respuestas morales, en lo esencial homogeneas, estan muy vinculadas al desarrollo emocional, tanto basico e individual (miedo o ira) como social (compasion o justicia). Aparecen a partir de los binomios emocionales placer/dolor y recompensa/castigo, que conducen al binomio moral basico bueno/malo. En su puesta en marcha intervienen la corteza prefrontal (ventromedial y dorsolateral), la corteza cingular anterior y el sulco temporal superior, que serian evaluativos y elaborativos, utilitaristas; tambien la insula, la amigdala y el hipotalamo, ejecutivos de las respuestas morales mas emocionales puras y rapidas. Asimismo, es importante el sistema de neuronas espejo (frontoparietal), que permite el aprendizaje motor y las conductas empaticas, con las que se vincula con la teoria de la mente. Conclusiones. El desarrollo del sentido moral y sus respuestas nos han permitido alcanzar una complejidad y convivencia social que redundan en beneficio de la especie e individuos. El conocimiento del funcionamiento moral esta influyendo tambien en territorios diversos de la neurocultura.

  10. [Therapeutic potential of bone marrow stem cells in cerebral infarction].

    PubMed

    Sánchez-Cruz, Gilberto; Milián-Rodríguez, Lismary

    2015-05-16

    Introduccion. Las celulas madre constituyen una alternativa terapeutica que se encuentra en fase de experimentacion para el infarto cerebral. Objetivo. Mostrar la evidencia cientifica existente sobre el potencial terapeutico de las celulas madre de la medula osea en esta enfermedad. Desarrollo. El infarto cerebral representa el 80% de las enfermedades cerebrovasculares. La trombolisis constituye la unica terapia aprobada, pero, por su estrecha ventana terapeutica, solo se aplica a un bajo porcentaje de los pacientes. De manera alternativa, los tratamientos neurorrestauradores, como el de celulas madre, pueden aplicarse en periodos mas prolongados. Por esta razon se efectuo una busqueda bibliografica en PubMed con el empleo de las palabras clave 'stem cells', 'bone marrow derived mononuclear cells' y 'stroke'. Se encontraron evidencias de seguridad y eficacia de dichas celulas en diferentes momentos evolutivos del infarto cerebral. Se identificaron estudios que en clinica y preclinica las recolectaron por puncion medular y en sangre periferica, y las trasplantaron directamente en el area infartada o por via intravascular. El efecto terapeutico se relaciona con sus propiedades de plasticidad celular y liberacion de factores troficos. Conclusiones. El concentrado de celulas mononucleares autologas, obtenido en sangre periferica o por puncion de la medula osea, y trasplantado por via intravenosa, es una factible opcion metodologica que permitira rapidamente incrementar el numero de ensayos clinicos en diferentes etapas evolutivas del infarto cerebral. Esta terapia muestra seguridad y eficacia; sin embargo, deben ampliarse las evidencias que avalen su generalizacion en humanos.

  11. Space-time evolution of a growth fold (Betic Cordillera, Spain). Evidences from 3D geometrical modelling

    NASA Astrophysics Data System (ADS)

    Martin-Rojas, Ivan; Alfaro, Pedro; Estévez, Antonio

    2014-05-01

    We present a study that encompasses several software tools (iGIS©, ArcGIS©, Autocad©, etc.) and data (geological mapping, high resolution digital topographic data, high resolution aerial photographs, etc.) to create a detailed 3D geometric model of an active fault propagation growth fold. This 3D model clearly shows structural features of the analysed fold, as well as growth relationships and sedimentary patterns. The results obtained permit us to discuss the kinematics and structural evolution of the fold and the fault in time and space. The study fault propagation fold is the Crevillente syncline. This fold represents the northern limit of the Bajo Segura Basin, an intermontane basin in the Eastern Betic Cordillera (SE Spain) developed from upper Miocene on. 3D features of the Crevillente syncline, including growth pattern, indicate that limb rotation and, consequently, fault activity was higher during Messinian than during Tortonian; consequently, fault activity was also higher. From Pliocene on our data point that limb rotation and fault activity steadies or probably decreases. This in time evolution of the Crevillente syncline is not the same all along the structure; actually the 3D geometric model indicates that observed lateral heterogeneity is related to along strike variation of fault displacement.

  12. Genome-wide evidence of Austronesian–Bantu admixture and cultural reversion in a hunter-gatherer group of Madagascar

    PubMed Central

    Pierron, Denis; Razafindrazaka, Harilanto; Pagani, Luca; Ricaut, François-Xavier; Antao, Tiago; Capredon, Mélanie; Sambo, Clément; Radimilahy, Chantal; Rakotoarisoa, Jean-Aimé; Blench, Roger M.; Letellier, Thierry; Kivisild, Toomas

    2014-01-01

    Linguistic and cultural evidence suggest that Madagascar was the final point of two major dispersals of Austronesian- and Bantu-speaking populations. Today, the Mikea are described as the last-known Malagasy population reported to be still practicing a hunter-gatherer lifestyle. It is unclear, however, whether the Mikea descend from a remnant population that existed before the arrival of Austronesian and Bantu agriculturalists or whether it is only their lifestyle that separates them from the other contemporary populations of South Madagascar. To address these questions we have performed a genome-wide analysis of >700,000 SNP markers on 21 Mikea, 24 Vezo, and 24 Temoro individuals, together with 50 individuals from Bajo and Lebbo populations from Indonesia. Our analyses of these data in the context of data available from other Southeast Asian and African populations reveal that all three Malagasy populations are derived from the same admixture event involving Austronesian and Bantu sources. In contrast to the fact that most of the vocabulary of the Malagasy speakers is derived from the Barito group of the Austronesian language family, we observe that only one-third of their genetic ancestry is related to the populations of the Java-Kalimantan-Sulawesi area. Because no additional ancestry components distinctive for the Mikea were found, it is likely that they have adopted their hunter-gatherer way of life through cultural reversion, and selection signals suggest a genetic adaptation to their new lifestyle. PMID:24395773

  13. Evaluation of a PCR-RFLP- ITS2 assay for discrimination of Anopheles species in northern and western Colombia

    PubMed Central

    Cienfuegos, Astrid V.; Rosero, Doris A.; Naranjo, Nelson; Luckhart, Shirley; Conn, Jan E.; Correa, Margarita M.

    2011-01-01

    Anopheles mosquitoes are routinely identified using morphological characters of the female that often lead to misidentification due to interspecies similarity and intraspecies variability. The aim of this work was to evaluate the applicability of a previously developed PCR-RFLP-ITS2 assay for accurate discrimination of anophelines in twelve localities spanning three Colombian malaria epidemiological regions: Atlantic Coast, Pacific Coast, and Uraba-Bajo Cauca-Alto Sinu Region. The evaluation of the stability of the PCR-RFLP patterns is required since variability of the ITS2 has been documented and may produce discrepancies in the patterns previously reported. The assay was used to evaluate species assignation of 939 mosquitoes identified by morphology. Strong agreement between the morphological and molecular identification was found for species An. albimanus, An. aquasalis, An. darlingi and An. triannulatus s.l. (p ≥ 0.05, kappa=1). However, disagreement was found for species An. nuneztovari s.l., An. neomaculipalpus, An. apicimacula and An. punctimacula (p ≤ 0.05; kappa ranging from 0.33–0.80). The ITS2-PCR-RFLP assay proved valuable for discriminating anopheline species of northern and western Colombia, especially those with overlapping morphology in the Oswaldoi Group. PMID:21345325

  14. [Food insecurity and social vulnerability in chiapas : the face of poverty].

    PubMed

    Martínez-Rodríguez, Julio C; García-Chong, Néstor R; Trujillo-Olivera, Laura E; Noriero-Escalante, Lucio

    2014-12-01

    Objetivo: estimar la frecuencia y distribución de seguridad o inseguridad alimentaria entre las familias en Chiapas, relacionar con condiciones de bienestar (CB) y características sociodemográficas. Método: Estudio transversal retrospectivo, descriptivo; incluye información proveniente de la Encuesta Nacional de Salud y Nutrición 2012 (ENSANUT 2012) en total 1,430 viviendas de Chiapas. La Inseguridad Alimentaria se midió usando la versión armonizada para México de la Escala Latinoamericana y Caribeña de Seguridad Alimentaria (ELCSA). Resultados: El 83% de los hogares en Chiapas tiene algún tipo de inseguridad alimentaria; 86.5% se concentra en los niveles socioeconómicos más bajos; sólo 15 de cada 100 hogares en zonas rurales registran seguridad alimentaria; 87% de los hogares beneficiarios de Oportunidades mantiene inseguridad para alimentarse. Discusión: Más de cuatro de cada cinco familias reportan inseguridad alimentaria, queda claro que los programas sociales focalizados destinados a abatir este rezago no impactan los niveles de acceso a los alimentos, lo que repercute en el potencial desarrollo físico e intelectual de los chiapanecos, convirtiéndose en un obstáculo más para el desarrollo de la entidad. Se plantea analizar y reorientar las políticas sociales.

  15. Seasonal changes in fish assemblage structure at a shallow seamount in the Gulf of California.

    PubMed

    Jorgensen, Salvador J; Klimley, A Peter; Muhlia-Melo, Arturo; Morgan, Steven G

    2016-01-01

    Seamounts have generally been identified as locations that can promote elevated productivity, biomass and predator biodiversity. These properties attract seamount-associated fisheries where elevated harvests can be obtained relative to surrounding areas. There exists large variation in the geological and oceanographic environment among the thousands of locations that fall within the broad definition of seamount. Global seamount surveys have revealed that not all seamounts are hotspots of biodiversity, and there remains a strong need to understand the mechanisms that underlie variation in species richness observed. We examined the process of fish species assembly at El Bajo Espiritu Santo (EBES) seamount in the Gulf of California over a five-year study period. To effectively quantify the relative abundance of fast-moving and schooling fishes in a 'blue water' habitat, we developed a simplified underwater visual census (UVC) methodology and analysis framework suitable for this setting and applicable to future studies in similar environments. We found correlations between seasonally changing community structure and variability in oceanographic conditions. Individual species responses to thermal habitat at EBES revealed three distinct assemblages, a 'fall assemblage' tracking warmer overall temperature, a 'spring assemblage' correlated with cooler temperature, and a 'year-round assemblage' with no significant response to temperature. Species richness was greatest in spring, when cool and warm water masses stratified the water column and a greater number of species from all three assemblages co-occurred. We discuss our findings in the context of potential mechanisms that could account for predator biodiversity at shallow seamounts. PMID:27651985

  16. [PREVALENCE OF DEHYDRATION BEFORE TRAINING IN PROFESIONAL CHILEAN SOCCER PLAYERS].

    PubMed

    Castro-Sepúlveda, Mauricio; Astudillo, Sebastian; Álvarez, Cristian; Zapata-Lamana, Rafael; Zbinden-Foncea, Hermann; Ramírez-Campillo, Rodrigo; Jorquera, Carlos

    2015-07-01

    Introducción: existen pocos estudios relacionados con el estado de hidratación pre-entrenamiento en futbolistas profesionales. Objetivo: determinar la prevalencia de deshidratación pre-entrenamiento en jugadores profesionales de fútbol. Métodos: se incluyeron un total de 156 jugadores de fútbol (edad 25,4 ± 5,2 años) de seis clubes profesionales chilenos. No se hicieron recomendaciones previas de hidratación ni de ingesta de alimentos, con el objetivo de evaluar el estado de hidratación bajo condiciones regulares “reales”. Se evaluó la masa corporal, la talla y la gravedad específica de la orina (GEO) antes de sus sesiones de entrenamiento. Resultados: la deshidratación (entre moderada y grave) pre-entrenamiento se observó en el 98% de los futbolistas. Discusión: la deshidratación pre-entrenamiento es el estado de hidratación más frecuente en los jugadores profesionales de fútbol de Chile, lo que puede afectar negativamente a su rendimiento y podría incrementar su riesgo de lesiones relacionadas con el calor.

  17. The flooding of the San Matías Gulf: The Northern Patagonia sea-level curve

    NASA Astrophysics Data System (ADS)

    Isla, Federico Ignacio

    2013-12-01

    Northern Patagonia is characterised by tectonic depressions below present sea level. Some of them are today flooded by the sea; others remain emerged although they are at altitudes of - 50 m (Bajo del Gualicho), - 35 m (Salinas Grandes) and - 7 m (Salina La Piedra). San Matías Gulf also was such an emerged depression below contemporary mean sea level during the Late Pleistocene. It flooded between 11,500 and 11,000 years ago, when the sea level surpassed the sill of the gulf (today 50 m below mean sea level) during postglacial sea-level rise. In those days, shrublands extended on the slopes of the tectonic depression. In-situ pieces of woods dredged from the bottom of the gulf at depths of 70 m gave a conventional age of 11,310 ± 150 years BP. We used the wood, together with dated shells from the continental shelf, and shells and organic matter dated from the San Blas, Negro and Chubut coastal plains to construct a sea-level curve. Sea level rise surpassed the present level somewhat before 6000 years BP, reaching a maximum stand of + 6 m. It has since gently diminished towards present sea level.

  18. Fructose intake: is there an association with uric acid levels in nondialysis-dependent chronic kidney disease patients?

    PubMed

    Vieira, Fernanda Oliveira; Leal, Viviane de Oliveira; Stockler-Pinto, Milena Barcza; Barros, Amanda de Faria; Borges, Natália Alvarenga; Lobo, Julie Calixto; Mafra, Denise

    2014-11-03

    Introducción: El consumo de fructosa ha aumentado dramáticamente en consecuencia del consumo de alimentos y bebidas azucaradas a base de fructosa. Pesquisas sugieren que el alto consumo de fructosa tiene una fuerte asociación con niveles de ácido úrico (AU) y empeora el pronóstico de la enfermedad renal crónica (ERC). Objetivo: El objetivo de este estudio fue investigar la influencia del consumo de fructosa en los niveles plasmáticos de ácido úrico en pacientes con ERC que no son dependiente de diálisis. Métodos: Cincuenta y dos pacientes en fases 3-5 (64,2±9,6 años, 24 hombres, tasa de filtración glomerular de 30,5±10,3ml/min) se dividieron en dos grupos: alto consumo de fructosa (>50g/día, n=29, 61,7± 9,3 años) y bajo consumo de fructosa (

  19. [Rosai-Dorfman disease presented with involvement of the adrenal gland. A clinical case reported].

    PubMed

    Flores-Carrillo, Víctor Manuel; Santaella-Torres, Félix; Sánchez-Martínez, Luis Carlos; Gómez-Lara, Miguel Humberto; Arellano-Poblete, Moisés; López Segura-Rueda, Eduardo; Villarroel-Noboa, Jorge

    2014-01-01

    INTRODUCCIÓN: la afectación extranodal de la glándula suprarrenal es una forma infrecuente de la histiocitosis sinusal con linfadenopatía masiva o enfermedad de Rosai-Dorfman. Aún se desconoce la etiopatogenia de esta enfermedad. Los síntomas y signos de presentación en la afectación adrenal son inciertos. Aunque es una enfermedad de buen pronóstico y curso clínico favorable, el bajo índice de sospecha y el difícil diagnóstico radiológico diferencial llevan a tratamiento radical en la mayoría de los casos. CASO CLÍNICO: se describe el caso de una paciente con enfermedad de Rosai-Dorfman en quien se identificó tumor adrenal derecho de 97 × 99 × 68 mm y tumor nodal infrahiliar izquierdo de 61 × 58 × 57 mm. El tratamiento incluyó adrenalectomía y vigilancia activa del tumor infrahilial mediante tomografía y gammagrama renal. La evolución de la paciente fue adecuada.

  20. Seasonal changes in fish assemblage structure at a shallow seamount in the Gulf of California.

    PubMed

    Jorgensen, Salvador J; Klimley, A Peter; Muhlia-Melo, Arturo; Morgan, Steven G

    2016-01-01

    Seamounts have generally been identified as locations that can promote elevated productivity, biomass and predator biodiversity. These properties attract seamount-associated fisheries where elevated harvests can be obtained relative to surrounding areas. There exists large variation in the geological and oceanographic environment among the thousands of locations that fall within the broad definition of seamount. Global seamount surveys have revealed that not all seamounts are hotspots of biodiversity, and there remains a strong need to understand the mechanisms that underlie variation in species richness observed. We examined the process of fish species assembly at El Bajo Espiritu Santo (EBES) seamount in the Gulf of California over a five-year study period. To effectively quantify the relative abundance of fast-moving and schooling fishes in a 'blue water' habitat, we developed a simplified underwater visual census (UVC) methodology and analysis framework suitable for this setting and applicable to future studies in similar environments. We found correlations between seasonally changing community structure and variability in oceanographic conditions. Individual species responses to thermal habitat at EBES revealed three distinct assemblages, a 'fall assemblage' tracking warmer overall temperature, a 'spring assemblage' correlated with cooler temperature, and a 'year-round assemblage' with no significant response to temperature. Species richness was greatest in spring, when cool and warm water masses stratified the water column and a greater number of species from all three assemblages co-occurred. We discuss our findings in the context of potential mechanisms that could account for predator biodiversity at shallow seamounts.

  1. [Early diagnostic accuracy of the O'Sullivan test in gestational diabetes].

    PubMed

    Rojas-Carrera, Sonia Irma; Márquez-Celedonio, Félix Guillermo; Lagunes-Mijangos, Adrián; González-Arriola, Víctor Manuel

    2013-01-01

    Objetivo: estimar la sensibilidad y la especificidad diagnóstica de la prueba de O'Sullivan para diabetes gestacional en el embarazo temprano. Metodología: se realizó estudio piloto que incluyó 50 mujeres con embarazo de bajo riesgo, sin alteración de glucosa. Se realizó la prueba de O'Sullivan para identificación de diabetes gestacional entre las semanas 14 y 23, y entre las semanas 24 y 28 para comparar resultados. Se administraron 50 g de glucosa, se cuantificó la glucemia a los 60 minutos y se consideró positiva si los valores eran = 140 mg/dL. Se calcularon sensibilidad, especificidad y valores predictivos. Resultados: la prueba de O'Sullivan entre las semanas 14 y 23 resultó positiva en tres de las gestantes (6 %), y la realizada entre las semanas 24 y 28 fue positiva en cuatro (8 %). No hubo diferencia estadística de la prueba entre ambas mediciones (p > 0.05). La sensibilidad fue de 75 % (IC 95 % de 30.1 % a 95.4 %), la especificidad de 100.0% (IC 95 % de 92.3 % a 100.0 %). Conclusiones: la prueba de O'Sullivan realizada entre las semanas 14 y 23 de gestación mostró buena sensibilidad y especificidad para identificar diabetes gestacional temprana.

  2. Extemporaneous clobazam suspensions for paediatric use prepared from commercially available tablets and pure drug.

    PubMed

    Buontempo, F; Moretton, M A; Quiroga, E; Chiappetta, D A

    2013-01-01

    Objetivo: Dos suspensiones orales acuosas de clobazam para uso pediátrico (5 mg/ml) fueron evaluadas para determinar su estabilidad fisicoquimica bajo diferentes condiciones de almacenamiento. Métodos: Las formulaciones fueron conservadas a 4 y 25 °C y el contenido de clobazam fue determinado mediante Cromatografía Líquida de Alta Performance. Cada una de las muestras fue analizada por triplicado a diferentes tiempos (0, 7, 14, 28 y 56 días). Resultados: Las suspensiones fueron formuladas satisfactoriamente a partir del principio activo puro y de comprimidos disponibles comercialmente. En ambos casos, las muestras presentaron una adecuada estabilidad física. El clobazam fue químicamente estable en las suspensiones acuosas durante los 56 días de duración del estudio a las dos temperaturas elegidas para su conservación. Conclusiones: Todas las formulaciones orales líquidas formuladas y evaluadas en este estudio pueden ser conservadas a 4 y 25 °C por al menos 56 días.

  3. Discovering the Ancient Maya From Space

    NASA Technical Reports Server (NTRS)

    Sever, T. L.

    2007-01-01

    The Peten region of northern Guatemala contains some of the most significant Mayan archeological sites in Latin America. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper, IKONOS, and QuickBird satellite, and airborne STAR-3i and AIRSAR radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as sites, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the bajos, which are seasonally flooded swamps that cover over 40% of the land surface. Through the use of various airborne and satellite sensor systems we have been able to detect and map ancient causeways, temples, reservoirs, and land forms, and locate these features on the ground through GPS technology. Recently, we have discovered that there is a strong relationship between a tropical forest vegetation signature in satellite imagery and the location of archeological sites. We believe that the use o f limestone and lime plasters in ancient Maya construction affects the moisture, nutrition, and plant species of the surface vegetation. We have mapped these vegetation signatures in the imagery and verified through field survey that they are indicative of archeological sites. Through the use of remote sensing and GIS technology it is possible to identify unrecorded archeological features in a dense tropical forest environment and monitor these cultural features for their protection.

  4. Discovering the Ancient Maya from Space

    NASA Technical Reports Server (NTRS)

    Sever, T. L.

    2008-01-01

    The Pet6n region of northern Guatemala contains some of the most significant Mayan archeological sites in Latin America. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper, IKONOS, and QuickBird satellite, and airborne STAR-3i and AIRSAR radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as sites, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the bajos, which are seasonally flooded swamps that cover over 40% of the land surface. Through the use of various airborne and satellite sensor systems we have been able to detect and map ancient causeways, temples, reservoirs, and land forms, and locate these features on the ground through GPS technology. Recently, we have discovered that there is a strong relationship between a tropical forest vegetation signature in satellite imagery and the location of archeological sites. We believe that the use of limestone and lime plasters in ancient Maya construction affects the moisture, nutrition, and plant species of the surface vegetation. We have mapped these vegetation signatures in the imagery and verified through field survey that they are indicative of archeological sites. Through the use of remote sensing and GIS technology it is possible to identify unrecorded archeological features in a dense tropical forest environment and monitor these cultural features for their protection.

  5. Cross-cultural examination of the five-factor model of drinking motives in Spanish and Canadian undergraduates.

    PubMed

    Mezquita, Laura; Stewart, Sherry H; Kuntsche, Emmanuel; Grant, Valerie V

    2016-06-14

    El objetivo de este estudio es testar la utilidad transcultural del Modified Drinking Motives Questionnaire-Revised (M DMQ-R) (Grant, Stewart, O’Connor, Blackwell, y Conrod, 2007). La muestra incluyó 571 universitarios españoles y 571 universitarios canadienses, de 18 a 22 años de edad (65,8% mujeres). El análisis factorial confirmatorio (AFC) mostró invarianza factorial entre las muestras. Los análisis de regresión mostraron que los motivos sociales, de animación y los bajos motivos de conformidad se relacionaban con la frecuencia y cantidad de alcohol consumida en la muestra completa. El país de origen no moderó la relación de los motivos con el consumo de alcohol. Los resultados sugieren que el M DMQ-R es un instrumento adecuado para comparar los motivos de consumo entre los estudiantes españoles y canadienses, y que los programas de prevención y tratamiento centrados en los aspectos motivacionales del consumo desarrollados en un país pueden generalizarse al otro.

  6. [Food neophobia: impact on food habits and acceptance of healthy foods in schoolchildren].

    PubMed

    Rodríguez-Tadeo, Alejandra; Patiño Villena, Begoña; Urquidez-Romero, Rene; Vidaña-Gaytán, María Elena; Periago Caston, María Jesús; Ros Berruezo, Gaspar; González Martinez-Lacuesta, Eduardo

    2014-09-21

    Introducción: En los niños la neofobia puede afectar las elecciones alimentarias y limitar la variedad de la dieta así como afectar la aceptación sensorial de nuevos alimentos. Objetivo: Identificar el impacto de la neofobia alimentaria en los hábitos alimentarios y preferencias de alimentos saludables en usuarios de comedores escolares en la ciudad de Murcia. Materiales y Métodos: Participaron 242 escolares de segundo y tercer ciclo de educación primaria, de 8-12 años, con estratificación por sexo y ciclo escolar. Se aplicó una encuesta de hábitos y preferencias alimentarias, neofobia alimentaria y aceptación de alimentos de consumo habitual en el comedor. Además se realizó una prueba sensorial y se midió el consumo de ensaladas y frutas en el comedor, mediante el método de pesada. Resultados: La prevalencia de neofobia fue de 16%, sin diferencia entre sexos, ciclo escolar, tiempo del uso del comedor, origen de los padres y tener sobrepeso o bajo peso. La neofobia se asoció a un detrimento en el consumo de verduras y frutas, el gusto por las legumbres y menor consumo de cereales y sus derivados en el desayuno y a menor preferencia de frutas, verduras y hortalizas (p.

  7. [CONTENT OF TRANS FATTY ACIDS IN FOOD PRODUCTS IN SPAIN].

    PubMed

    Robledo de Dios, Teresa; Dal Re Saavedra, M Ángeles; Villar Villalba, Carmen; Pérez-Farinós, Napoleón

    2015-09-01

    Introducción: los ácidos grasos trans están asociados con problemas de salud, como enfermedad coronaria o diabetes. Objetivos: conocer la cantidad de ácidos grasos trans en los alimentos en España, y el porcentaje que representan con respecto al total de los ácidos grasos. Métodos: se estudió el contenido en ácidos grasos de 443 alimentos adquiridos en España en el año 2010, y clasificados en grupos. Determinación analítica de grasas en los productos mediante cromatografía de gases. Se calcularon estimadores de tendencia central y dispersión de la cantidad de ácidos grasos trans en cada grupo (g de ácidos grasos trans/100 g de producto). Se calculó el porcentaje de ácidos grasos trans con respecto a la grasa total en cada grupo. Resultados: los productos se agruparon en 42 grupos. En todos, salvo uno, la mediana de ácidos grasos trans fue inferior a 0,55 g/100 g de producto. El 83 % de los grupos tienen menos del 2 % de ácidos grasos trans con respecto a las grasas totales, y el 71 %, menos del 1 %. Discusión: el contenido de AGT en los alimentos en España es bajo y no representa actualmente un problema de salud pública.

  8. Prediction and verification of possible reef-fish spawning aggregation sites in Los Roques Archipelago National Park, Venezuela.

    PubMed

    Boomhower, J; Romero, M; Posada, J; Kobara, S; Heyman, W

    2010-09-01

    This study attempts to predict and verify possible spawning aggregation sites and times in the Los Roques Archipelago National Park, Venezuela, based on physical reef characteristics and the knowledge of experienced local fishermen. Three possible aggregation sites were selected for monitoring based on satellite images, low-cost bathymetric mapping and interviews with experienced local fishermen. Abundances and sizes of 18 species that are known to form reproductive aggregations were monitored at these sites using underwater visual census for 7 days after each full moon from February to August, 2007. While spawning events were not observed, possible indirect evidence of spawning aggregations was found for Lutjanus analis at Cayo Sal and Boca de Sebastopol, Lutjanus apodus at Cayo Sal, Lutjanus cyanopterus at Cayo Sal and Piedra La Guasa and Epinephelus guttatus at Bajo California and Cayo de Agua. Additionally, indirect evidence was identified for the past existence of a spawning aggregation of Epinephelus striatus in the northern part of the archipelago, which may have been eliminated by overfishing c.15 years ago. Bathymetric mapping showed that the shelf edge at sites monitored in this study was shallower than at spawning aggregation sites in other parts of the Caribbean, and that sites were not proximal to deep water. While this study does not prove the existence or locations of spawning aggregations of reef fishes in the archipelago, it does add insight to a growing understanding of generalities in the relationship between seafloor characteristics and the locations of transient reef-fish spawning aggregations in the Caribbean.

  9. [Comorbidity of panic disorder and alcoholism in a sample of 100 alcoholic patients].

    PubMed

    Segui, J; Salvador, L; Canet, J; Herrera, C; Aragón, C

    1994-01-01

    Among one hundred patients with alcohol dependence (DSM-III-R) studied in a drug abuse center in the "Bajo Llobregat" area (Barcelona industrial belt it was detected that 27% had life time rate of panic disorder. The age of onset of alcoholism was earlier than the one for panic disorder. In 78.8% of these patients alcoholismo appeared first. 70.4% refer worsening of the panic attacks when drinking large amounts of alcohol. Patients with Panic Disorder: a) are younger (p < 0.05); b) have attended school longer and have higher education (p < 0.01); c) have more alcoholism family history (p < 0.05); d) have more major depressive disorders (0.05) and dysthimic disorder (p < 0.01); e) Worse social functioning according to the GAS (p < 0.01); f) higher score for the Psychological disorders Scale (p < 0.001) and a lower performance at work (p < 0.001) measured by the ASI. The clinical significance of these findings is discussed. PMID:7484297

  10. [In vitro effect of the S3Pvac vaccine against cysticercosis in human mononucleate cells].

    PubMed

    Díaz-Orea, María Alicia; Mijares, José Miguel; Arcega, Raúl; Gómez-Conde, Eduardo; Castellanos-Sánchez, Víctor Omar; Briones-Rojas, Rosendo; Flores-Alonso, Juan Carlos; Marín-Briones, Miguel Ángel; Santos-López, Gerardo

    2013-05-01

    Introduccion. La neurocisticercosis (NCC) es una infeccion parasitaria generada por el establecimiento de cisticercos de Taenia solium en el sistema nervioso central. La fase larvaria del parasito tambien afecta al cerdo, que es el huesped intermediario indispensable para la transmision. Por tal motivo, muchos investigadores se han enfocado en identificar antigenos protectores para prevenir la cisticercosis porcina e interrumpir la transmision. Entre ellos figuran los antigenos de la vacuna S3Pvac, constituida por tres peptidos protectores: KETc1, KETc12 y GK1. Objetivo. Evaluar el efecto de los peptidos vacunales KETc1, KETc12 y GK1 en celulas mononucleares de pacientes con NCC e individuos sanos. Sujetos y metodos. Estudio comparativo, prospectivo y transversal. Se analizo la proliferacion y el perfil de citocinas inducidos por los tres peptidos en celulas mononucleares de tres pacientes con NCC activa, 16 pacientes con NCC calcificada y 16 sujetos sanos. Resultados. KETc1 induce bajos niveles de proliferacion en las celulas de los pacientes con NCC activa y controlada, tanto en linfocitos como en monocitos. KETc12 y GK-1 inducen niveles positivos de proliferacion de monocitos en sujetos sanos. Conclusiones. El peptido KETc1 podria usarse como coadyuvante en el tratamiento de los pacientes con NCC activa, ya que indujo una respuesta Th2; y el peptido GK1, como estimulador del monocito/macrofago en inmunizaciones con otras proteinas.

  11. [Value of electroencephalography in the early detection of neonatal leucinosis].

    PubMed

    Pardal-Fernandez, J M; Carrascosa-Romero, M C; Grande, A; Martinez-Gonzalez, M; Godes-Medrano, B

    2016-08-16

    Introduccion. La leucinosis es una metabolopatia neonatal grave. Es consecuencia del deficit enzimatico determinado geneticamente del complejo descarboxilasa-dihidrolipoil transacilasa y dihidrolipoil deshidrogenasa, y del acumulo consecuente de los metabolitos precursores, aminoacidos ramificados de cadena larga y sus alfa-cetoacidos. Son potentes neurotoxicos, responsables del rapido establecimiento de edema y desmielinizacion cerebral difusa. La demora en el diagnostico suele provocar graves secuelas psicomotoras o incluso la muerte. Caso clinico. Se presenta una paciente neonata con encefalopatia neonatal grave, crisis epilepticas y un electroencefalograma (EEG) con unas caracteristicas especiales que oriento el diagnostico hacia una posible leucinosis. El diagnostico temprano permitio instaurar rapidamente el tratamiento especifico y conseguir una evolucion favorable de la paciente. Conclusiones. El EEG en pacientes con sospecha de encefalopatia neonatal ofrece informacion funcional de alta rentabilidad con un bajo coste, en especial por promover diagnosticos y tratamientos tempranos. El EEG en la leucinosis presenta signos peculiares, reconocibles en periodos tempranos en la mayor parte de los afectados, como ocurrio en el caso descrito. Parece recomendable integrar el EEG en el cribado de encefalopatias neonatales por ser una tecnica diagnostica valiosa, inocua y, por lo general, accesible y especialmente de ayuda en metabolopatias tratables, como la leucinosis.

  12. Students of dietetics & nutrition; a high risk group for eating disorders?

    PubMed

    Mealha, Vanessa; Ferreira, Catarina; Guerra, Inês; Ravasco, Paula

    2013-01-01

    Introducción: Los cambios en la conducta alimentaria de los estudiantes universitarios son comunes y se han estudiado ampliamente. Aunque el riesgo de desarrollo de trastornos de la alimentación parece ser obvio entre los estudiantes de nutrición, hay una falta de investigación en este campo. Este estudio se propuso: determinar el riesgo de desarrollar trastornos de la alimentación en los estudiantes de Dietética y Nutrición mediante la comparación entre las conductas alimentarias, los hábitos dietéticos, el estado nutricional, la composición corporal y la actividad física con respecto a la de otros estudiantes (de grados de la salud y no relacionados con la salud). Métodos: Estudio comparativo transversal. La muestra comprendía 189 estudiantes mujeres, con edades entre 18 y 25 años (20,3 ± 2,0) de dos universidades públicas portuguesas. En todas las estudiantes se midió el peso, la talla, el porcentaje de masa grasa y la circunferencia de la cintura, y todas ellas contestaron cuatro cuestionarios validados que evaluaban la conducta alimentaria, los patrones de alimentación y la actividad física. Resultados: Hubo un riesgo bajo de desarrollar trastornos de la alimentación en estas estudiantes (4,2%). No hubo diferencias significativas entre las estudiantes de DN, salud y otras disciplinas no relacionadas con la salud con respecto a la conducta alimentaria, el estado nutricional o la composición corporal, lo que contrastaba con diferencias en algunos hábitos dietéticos y la actividad física (p < 0,05). Conclusiones: A pesar del riesgo bajo de trastornos de la alimentación entre las estudiantes de DN, un gran porcentaje de ellas tenía preocupación por el peso corporal. Las estudiantes de DN tenían los mayores porcentajes de peso normal, ausencia de riesgo cardiometabólico de acuerdo a la circunferencia de la cintura y la masa grasa normal. Estas estudiantes tenían los hábitos dietéticos más saludables y también practicaban una

  13. Geology of the epithermal Ag-Au Huevos Verdes vein system and San José district, Deseado massif, Patagonia, Argentina

    NASA Astrophysics Data System (ADS)

    Dietrich, Andreas; Gutierrez, Ronald; Nelson, Eric P.; Layer, Paul W.

    2012-03-01

    The San José district is located in the northwest part of the Deseado massif and hosts a number of epithermal Ag-Au quartz veins of intermediate sulfidation style, including the Huevos Verdes vein system. Veins are hosted by andesitic rocks of the Bajo Pobre Formation and locally by rhyodacitic pyroclastic rocks of the Chon Aike Formation. New 40Ar/39Ar constraints on the age of host rocks and mineralization define Late Jurassic ages of 151.3 ± 0.7 Ma to 144.7 ± 0.1 Ma for volcanic rocks of the Bajo Pobre Formation and of 147.6 ± 1.1 Ma for the Chon Aike Formation. Illite ages of the Huevos Verdes vein system of 140.8 ± 0.2 and 140.5 ± 0.3 Ma are 4 m.y. younger than the volcanic host rock unit. These age dates are among the youngest reported for Jurassic volcanism in the Deseado massif and correlate well with the regional context of magmatic and hydrothermal activity. The Huevos Verdes vein system has a strike length of 2,000 m, with several ore shoots along strike. The vein consists of a pre-ore stage and three main ore stages. Early barren quartz and chalcedony are followed by a mottled quartz stage of coarse saccharoidal quartz with irregular streaks and discontinuous bands of sulfide-rich material. The banded quartz-sulfide stage consists of sulfide-rich bands alternating with bands of quartz and bands of chlorite ± illite. Late-stage sulfide-rich veinlets are associated with kaolinite gangue. Ore minerals are argentite and electrum, together with pyrite, sphalerite, galena, chalcopyrite, minor bornite, covellite, and ruby silver. Wall rock alteration is characterized by narrow (< 3 m) halos of illite and illite/smectite next to veins, grading outward into propylitic alteration. Gangue minerals are dominantly massive quartz intergrown with minor to accessory adularia. Epidote, illite, illite/smectite, and, preferentially at deeper levels, Fe-chlorite gangue indicate near-neutral pH hydrothermal fluids at temperatures of >220°C. Kaolinite occurring with

  14. [Food sources and adequacy of intake of omega 3 and omega-6 fatty acids in a representative sample of Spanish adults].

    PubMed

    Ortega Anta, Rosa M; González Rodríguez, Liliana G; Villalobos Cruz, Tania K; Perea Sánchez, José Miguel; Aparicio Vizuete, Aránzazu; López Sobaler, Ana María

    2013-11-01

    Introducción y Objetivos: Teniendo en cuenta la importancia sanitaria del aporte de ácidos grasos omega 3 y omega 6 y ante la escasez de estudios sobre el tema en colectivos españoles se plantea la conveniencia de conocer la ingesta de estos ácidos grasos, su adecuación a los objetivos nutricionales marcados y sus fuentes alimentarias en una muestra representativa de la población española. Métodos: Se ha estudiado un colectivo de 1068 adultos (521 varones y 547 mujeres) de 17 a 60 años, seleccionados en diez provincias españolas, que constituyen una muestra representativa de la población, a nivel nacional. Se determino la ingesta de ácidos grasos poliinsaturados (AGP), ácidos grasos omega-3, α-linolénico (ALA), ácido eicosapentaenoico (EPA), docosahexaenoico (DHA), ácidos grasos omega-6, ácido linoléico (LA) y araquidónico, en g/día y en porcentaje de la energía, utilizando un “Registro del consumo de alimentos” durante 3 días consecutivos, incluyendo un domingo, recogiendo también datos personales, sanitarios y antropométricos de los individuos estudiados. Resultados y Discusión: Mientras que la ingesta de grasa total y grasa saturada fue superior a la marcada como aconsejable en el 89.2% y 93.3% de los individuos, respectivamente, sin embargo con la ingesta de AGP sucede lo contrario, siendo más frecuente el aporte insuficiente (79.2% de los estudiados tienen ingesta menor del 6% de la energía). Resulta especialmente bajo el aporte de ácidos grasos omega-3 (1.850.82 g/día), que proporcionan menos del 1% de la energía en el 85.3% de los individuos, en concreto el ALA (1.400.55 g/día) no supera el 0.5% de la energía en el 53.7% de los casos y el EPA+DHA (0.550.58 g/día) no superan los 0.5 g/día en el 64.6%. Por otra parte, el aporte de ácidos grasos omega-6 fue más adecuado (10,953.79 g/día) y en concreto el de LA (10.773.76 g/día) supuso menos del 3% de la energía en el 25.5% de los estudiados. Las

  15. IMPACT OF IMPROVED FAT-MEAT PRODUCTS CONSUMPTION ON ANTHROPOMETRIC MARKERS AND NUTRIENT INTAKES OF MALE VOLUNTEERS AT INCREASED CARDIOVASCULAR RISK.

    PubMed

    Celada, Paloma; Delgado-Pando, Gonzalo; Olmedilla-Alonso, Begoña; Jiménez-Colmenero, Francisco; Ruperto, Mar; Sánchez-Muniz, Francisco J

    2015-08-01

    Introducción: la carne es una matriz adecuada para la inclusión de ingredientes funcionales. En un estudio no secuencial controlado y aleatorio se evaluó el impacto del consumo de productos cárnicos, en los que se sustituyó la grasa animal por una combinación de aceite de oliva, de linaza y de pescado, sobre la ingesta de energía y nutrientes y sobre los marcadores antropométricos. Métodos: dieciocho voluntarios con elevado riesgo cardiovascular consumieron semanalmente 200 g de salchichas tipo frankfurt y 250 g de paté durante tres períodos sucesivos de 4 semanas (bajo en grasa (RF); enriquecidos en n-3 (n-3RF), y grasa normal (NF)), separados por un lavado de 4 semanas. Se evaluó la ingesta de nutrientes y energía, el índice de alimentación saludable (HEI) y los cambios antropométricos. Resultados: hubo diferencias significativas entre períodos para las tasas de cambio de la grasa corporal y de la relación cintura/cadera (p = 0,018 y p = 0,031, respectivamente), disminuyendo la masa grasa, el perímetro de la cintura y la relación cintura/cadera en el periodo RF, e incrementándose la grasa corporal en el periodo NF (todos p = 0,05). En el período n-3RF las tasas de cambio de IMC y del peso ideal correlacionaron inversa y significativamente (p = 0.003 y p = 0.006, respectivamente) con el cociente hidratos de carbono/AGS. El HEI inicial de las dietas fue muy bajo (valor medio < 60). La contribución energética de carbohidratos, grasa y proteínas fue 40%, 41% y 16%, respectivamente. Más del 33% de los voluntarios no cubrían al inicio el 70% de las RDA para minerales y vitaminas. La intervención mejoró en todos los períodos la ingesta de Zn, Ca, equivalentes de retinol, folatos y vitamina B12. En el período n-3RF incrementó los AGPn-3 y redujo el cociente n-6/n-3. Conclusión: los productos cárnicos con menos grasa o enriquecidos en AGP n-3 son alimentos funcionales para personas con sobrepeso/obesidad, ya que su consumo mejora los

  16. Fluid evolution in a volcanic-hosted epithermal carbonate-base metal-gold vein system: Alto de la Blenda, Farallón Negro, Argentina

    NASA Astrophysics Data System (ADS)

    Márquez-Zavalía, M. Florencia; Heinrich, Christoph A.

    2016-10-01

    Alto de la Blenda is a ˜6.6-Ma intermediate-sulphidation epithermal vein system in the Farallón Negro Volcanic Complex, which also hosts the 7.1-Ma porphyry-Cu-Au deposit of Bajo de la Alumbrera. The epithermal vein system is characterised by a large extent and continuity (2 km × 400 m open to depth × 6 m maximum width) and an average gold grade of ˜8 g/t. The vein is best developed within an intrusion of a fine-grained equigranular monzonite, interpreted as the central conduit of a stratovolcano whose extrusive activity ended prior to porphyry-Cu-Au emplacement at Bajo de la Alumbrera, which is in turn cut by minor epithermal veins. The Alto de la Blenda vein consists predominantly of variably Mn-rich carbonates and quartz, with a few percent of pyrite, sphalerite, galena and other sulphide and sulphosalt minerals. Four phases of vein opening, hydrothermal mineralisation and repeated brecciation can be correlated between different vein segments. Stages 2 and 3 contain the greatest fraction of sulphide and gold. They are separated by the emplacement of a polymictic breccia containing clasts of quartz feldspar porphyry as well as basement rocks. Fluid inclusions in quartz related to stages 2 to 4 are liquid rich with 2-4 wt% NaCl(eq). They homogenise between 160 and 300 °C, with very consistent values within each assemblage. Vapour inclusions are practically absent in the epithermal vein. Quartz fragments in the polymictic breccia contain inclusions of intermediate to vapour-like density and similar low salinity (˜3 wt% NaCl(eq)), besides rare brine inclusions containing halite. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of epithermal inclusions indicate high concentrations of K, Fe, As, Sb, Cs, and Pb that significantly vary within and through subsequent vein stages. Careful consideration of detection limits for individual inclusions shows high gold concentrations of ˜0.5 to 3 ppm dissolved in the ore fluid, which

  17. APPLICATILITY OF THE VISCERAL ADIPOSITY INDEX (VAI) IN THE PREDICTION OF THE COMPONENTS OF THE METABOLIC SYNDROME IN ELDERLY.

    PubMed

    Goldani, Heloisa; Adami, Fernanda Scherer; Antunes, Maria Terezinha; Rosa, Luis Henrique; Fassina, Patrícia; Quevedo Grave, Magali Terezinha; Morelo Dal Bosco, Simone

    2015-10-01

    La evaluación nutricional puede detectar un estado de desnutrición, sobrepeso y riesgo cardiometabólico en los ancianos. Fácil de aplicar, los instrumentos permiten la identificación de factores de riesgo de enfermedades cardiovasculares (ECV). Objetivo: analizar la aplicabilidad del Índice de Adiposidad Visceral (VAI) en la predicción de los componentes del SM en los ancianos. Métodos: estudio transversal con 221 personas mayores con una edad media de 70,65 ± 7,34 años; 53,4% mujeres y 46,4% hombres. Se obtuvieron peso, talla, circunferencia de la cintura (CC), glucosa en ayunas, triglicéridos (TG), colesterol total (CT), colesterol HDL (HDL-C), colesterol LDL (LDL-C) y presión arterial (PA), así como información acerca del estilo de vida. No se calcularon el índice de masa corporal (IMC), la relación cintura-cadera (WHR) y el VAI. Las medidas de adiposidad se compararon con los componentes de la MS, y para el VAI no se determinó la capacidad de predecir la ocurrencia de los componentes del SM. Resultados: el análisis de la asociación entre las variables bioquímicas y de presión y los componentes del SM con los indicadores antropométricos de obesidad evidencia que existe una correlación directa y significativa entre el índice de masa corporal, el peso y el VAI con la glucosa en sangre, colesterol HDL y TG (p < 0,01); el VAI fue el indicador con la correlación más fuerte para todos los parámetros. El WC se asoció significativamente con el HDL y TG, y el RHO solo con el HDL. En lo que respecta a la aplicabilidad de la VAI en la determinación del riesgo relativo de aparición de los componentes del SM, el VAI era buen predictor de obesidad abdominal (OR = 1,27, p < 0,001), hiperglucemia (OR = 1,10, p = 0,043), hipertrigliceridemia (OR = 3,64, p < 0,001) y bajos niveles de HDL-c (OR = 2,26, p < 0,001). Conclusión: el VAI mostró asociación con componentes del síndrome metabólico en los hombres y las mujeres con mayor riesgo de obesidad

  18. [In Process Citation].

    PubMed

    Zhu, Jin-Zhou; Li, Chun-Xiao; Dai, Yi-Ning; Zhao, De-Jian; Fang, Zhi-Yun; Wan, Xing-Yong; Zhu, Hua-Tuo; Wang, Yu-Ming; Yu, Chao-Hui; Li, You-Ming

    2016-03-25

    Introducción: la betatrofina es una novedosa adipoquina que provoca la proliferación de células β pancreáticas e interviene en el metabolismo de los lípidos. Objetivos: el propósito de este estudio es evaluar el papel de la betatrofina en el síndrome metabólico. Método: se llevó a cabo un estudio hospitalario de casos y controles según sexo y edad. El nivel de betatrofina en suero fue evaluado mediante ensayo por inmunoabsorción ligado a enzimas. Se midieron las concentraciones en suero de 12 adipoquinas para evaluar las asociaciones con la betatrofina usando los kits comerciales Adipokine Magnetic Bead Panel. Los análisis estadísticos incluyeron correlación bivariada, análisis de curva ROC y análisis de regresión lineal multivariable. Resultados: el nivel de betatrofina en suero fue más elevado en pacientes con síndrome metabólico (997,36 ± 475,92 pg/ml, p = 0,001) que en los controles (735,35 ± 526,51 pg/ml). Frente al tercil más bajo, el tercil más alto del nivel de betatrofina mostró una asociación con mayor riesgo de síndrome metabólico (odds ratio ajustado = 3,521, intervalo de confianza [IC] 95% [1,191-10,413], p = 0,023). Se desarrolló la curva ROC de betatrofina para pronosticar la presencia de síndrome metabólico (área bajo la curva ROC = 0,682 [95% IC, 0,597-0,767], p < 0,001). Además, la betatrofina mostró correlación con distintos parámetros, como edad (r = 0,286, p < 0,001), índice de masa corporal (r = 0,160, p = 0,046), índice cintura-cadera (r = 0,241, p = 0,002), lipoproteína de alta densidad (r = -0,167, p = 0,037), lipoproteína de baja densidad (r = -0,195, p = 0,015), glucosa plasmática en ayunas (r = 0,266, p = 0,001), hemoglobina A1C (r = 0,314, p < 0,001), índice de resistencia a la insulina mediante HOMA (r = 0,272, p = 0,001) y diversas adipoquinas, entre ellas resistina (r = 0,571, p < 0,001), interleucina-8 (r = 0,435, p < 0,001), factor de necrosis tumoral alfa (r = 0,295, p = 0,011) y

  19. Fluid evolution in a volcanic-hosted epithermal carbonate-base metal-gold vein system: Alto de la Blenda, Farallón Negro, Argentina

    NASA Astrophysics Data System (ADS)

    Márquez-Zavalía, M. Florencia; Heinrich, Christoph A.

    2016-03-01

    Alto de la Blenda is a ˜6.6-Ma intermediate-sulphidation epithermal vein system in the Farallón Negro Volcanic Complex, which also hosts the 7.1-Ma porphyry-Cu-Au deposit of Bajo de la Alumbrera. The epithermal vein system is characterised by a large extent and continuity (2 km × 400 m open to depth × 6 m maximum width) and an average gold grade of ˜8 g/t. The vein is best developed within an intrusion of a fine-grained equigranular monzonite, interpreted as the central conduit of a stratovolcano whose extrusive activity ended prior to porphyry-Cu-Au emplacement at Bajo de la Alumbrera, which is in turn cut by minor epithermal veins. The Alto de la Blenda vein consists predominantly of variably Mn-rich carbonates and quartz, with a few percent of pyrite, sphalerite, galena and other sulphide and sulphosalt minerals. Four phases of vein opening, hydrothermal mineralisation and repeated brecciation can be correlated between different vein segments. Stages 2 and 3 contain the greatest fraction of sulphide and gold. They are separated by the emplacement of a polymictic breccia containing clasts of quartz feldspar porphyry as well as basement rocks. Fluid inclusions in quartz related to stages 2 to 4 are liquid rich with 2-4 wt% NaCl(eq). They homogenise between 160 and 300 °C, with very consistent values within each assemblage. Vapour inclusions are practically absent in the epithermal vein. Quartz fragments in the polymictic breccia contain inclusions of intermediate to vapour-like density and similar low salinity (˜3 wt% NaCl(eq)), besides rare brine inclusions containing halite. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of epithermal inclusions indicate high concentrations of K, Fe, As, Sb, Cs, and Pb that significantly vary within and through subsequent vein stages. Careful consideration of detection limits for individual inclusions shows high gold concentrations of ˜0.5 to 3 ppm dissolved in the ore fluid, which

  20. Effects of pre-irradiation conditioning of Medfly pupae (Diptera: Tephritidae): Hypoxia and quality of sterile males

    SciTech Connect

    Nestel, D.; Nemny-Lavy, E.; Islam, S.M.; Wornoayporn, V.; Caceres, C.

    2007-03-15

    Irradiation of pupae in sterile insect technique (SIT) projects is usually undertaken in hypoxic atmospheres, which have been shown to lessen the deleterious effects of irradiation on the quality of adult sterile flies. Although this is the accepted technology in most mass-rearing and sterilization facilities, to date no information has been generated on the actual levels of oxygen (O{sub 2}) in pupae-packing containers during irradiation. The present study utilized recently-developed technology to investigate the O{sub 2} level inside bags in which pupae of Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) are packed prior to irradiation, the ability of pupae to create hypoxic environments in these bags, and the effect of O{sub 2} atmospheres on the quality of irradiated males. Pupae, 1 d before adult emergence, were shown to deplete the O{sub 2} level in sealed bags in approximately 1 h. The rate of O{sub 2} consumption was dependent upon pupal age and incubation temperature. Incubation temperature did not significantly affect the quality of pupae or mating capacity of resultant adult males if pupae were irradiated under maximal hypoxic conditions inside packing bags. In contrast, mating competitiveness drastically decreased when pupae were irradiated under ambient O{sub 2} conditions, with the packing bag open. There was no difference in the mating capacity of males when pupae were irradiated in sealed bags under either 10% or 2% O{sub 2} levels, or under maximal hypoxia. Normal doses of fluorescent dye, applied to pupae to mark sterile flies, did not affect the ability of pupae to create hypoxic conditions inside packing bags, nor the quality control parameters of either pupae or adults. Current practices in mass-rearing facilities are discussed in the light of these results. (author) [Spanish] La irradiacion de pupas en proyectos de mosca esteril usualmente se hace bajo condiciones de hipoxia. Esta condicion ha demostrado ser menos detrimente a

  1. [Results of PROMESA I study; efficacy and safety of a very low calorie diet application and following alimentary reeducation with the PronoKal® method in the treatment of excess of weight].

    PubMed

    Martínez-Riquelme, Amparo; Sajoux, Ignacio; Fondevila, Joan

    2014-02-01

    Introducción y Objetivos: El objetivo de este estudio fue evaluar la eficacia en la reducción de peso con la utilización de dieta de muy bajo aporte calórico cetogénica y posterior reeducación alimentaria según el método PronoKal ® en pacientes con sobrepeso y obesidad, y la seguridad durante su aplicación. Métodos: Estudio multicéntrico observacional, retrospectivo en que se analizaron estadísticamente variables descriptivas de los pacientes, variables relacionadas con el cambio ponderal, circunferencia de cintura abdominal, y bioquímica general al final de cada una de las etapas de tratamiento, y los acontecimientos adversos referidos en cada visita a lo largo del tratamiento. Resultados: De los 426 casos evaluables, el 62,3% de los pacientes eran obesos. El 16,7% presentaba hiperlipemia, el 2,3% diabetes mellitus tipo 2, y el 4,8% hipertensión arterial. Al final del tratamiento la media de peso perdido fue de 17,1 ± 8,0 kg (p < 0,001), con una reducción del IMC de 6,2 ± 3,0 kg/m2. El 54,2% de pacientes alcanzó la situación de normopeso (35,9% de los obesos), siendo mayor en mujeres que en hombres (62,5% vs 28,2%, respectivamente; p < 0,001). El perímetro de la cintura se redujo en 17,3 ± 9,5 cm. Hubo mejora de todos los parámetros analíticos en los pacientes diabéticos, hipertensos y dislipémicos, alcanzándose la significación estadística (p < 0,05) en la disminución de glucosa (28,8%) en diabéticos, en la disminución de glucosa (12,7%) y colesterol (14,5%) en hipertensos, y en la disminución de glucosa (11,7%), colesterol total (11,9%), colesterol LDL (11,3%) y triglicéridos (37,9%) en dislipémicos. La aparición de acontecimientos adversos se refirió en el 23,7% de los pacientes, principalmente estreñimiento (23,9%). Conclusiones: El método PronoKal® es un método eficaz y seguro de abordaje del exceso de peso, cuando se realiza de forma completa y bajo estricto control clínico multidisciplinar, mejorando diferentes par

  2. EFFECT OF CHIA SEED (SALVIA HISPANICA L.) CONSUMPTION ON CARDIOVASCULAR RISK FACTORS IN HUMANS: A SYSTEMATIC REVIEW.

    PubMed

    de Souza Ferreira, Cynthia; dd Sousa Fomes, Lucilia de Fátima; da Silva, Gilze Espirito Santo; Rosa, Glorimar

    2015-11-01

    Introducción: la chía es una semilla rica en nutrientes tales como proteínas; ácidos grasos omega 3, especialmente ácido alfa-linolénico (ALA); minerales; fibras y antioxidantes. Se han hecho esfuerzos para evaluar si el consumo humano de chía puede reducir los factores de riesgo cardiovascular; sin embargo, no se ha establecido como eficaz y los resultados de los pocos estudios que han examinado la cuestión son incompatibles. Objetivo: sistematizar los hallazgos de los estudios que evaluaron el efecto del consumo de la semilla de chía, ya sea molida o entera, tiene en la prevención/control de los factores de riesgo cardiovascular en los seres humanos. Métodos: se trata de una revisión sistemática de la literatura (SLR), sin metaanálisis. Los artículos escrutados eran identificados en las bases de datos Lilacs electrónicos, Medline (PubMed versión), Cochrane, Scielo, Scopus y Web of Science bajo la palabra clave “dyslipidemia” o “dislipidemia”, “hyperlipidemia” o “hiperlipidemia”, “obesity” o “obesidade”, “salvia” o “salviahispanica”, “Lamiaceae” o “chia”, “hypertension” o “hipertensão”, “hypertrygliceridemia” o “hipertrigliceridemia” y “riscocardiovascular” o “cardiovascularrisk”. Elegimos para nuestra selección artículos en inglés, portugues o español sobre ensayos clínicos en seres humanos publicados en los últimos diez años. Los sesgos de análisis de riesgo se realizaron considerando seis de los ocho criterios del Manual Cochrane para Revisiones Sistemáticas de Intervenciones Versión 5.1. Resultados: siete estudios (n = 200) encajan con los criterios de inclusión. De los ensayos clínicos seleccionados, solo uno no fue aleatorio. Cinco de los estudios fueron experimentos ciegos. Dos de los estudios eran ensayos agudos, ambos asignados al azar. De las intervenciones de semillas de chía, un estudio mostró una disminución significativa de la presión arterial sist

  3. EVALUATION OF THE EFFECTS OF A PROGRAMME PROMOTING ADEQUATE AND HEALTHY EATING ON ADOLESCENT HEALTH MARKERS: AN INTERVENTIONAL STUDY.

    PubMed

    Brito Beck da Silva, Karine; Leovigildo Fiaccone, Rosemeire; Couto, Ricardo David; Ribeiro-Silva, Rita de Cássia

    2015-10-01

    Objetivo: evaluar las repercusiones de un protocolo de promoción de una alimentación adecuada y saludable en los parámetros de salud de adolescentes. Métodos: se trata de un estudio de intervención, controlado, con una duración de nueve meses, en el cual participaron estudiantes, con una edad entre 10 y 17 años, matriculados en dos escuelas (intervención/ control) situadas en un barrio pobre del municipio de Salvador (Bahia), Brasil. Fueron previstas para la escuela bajo intervención acciones de promoción de una alimentación adecuada y saludable, con base en el Guia Alimentar para a População Brasileira (Guía Alimentaria para la Población Brasileña). Con el propósito de evaluar el efecto de tales acciones, todos los alumnos fueron sometidos a los exámenes bioquímicos, de maduración y antropométricos al principio y al final de los nueve meses. Además, contestaron a un cuestionario sobre consumo alimentario, actividad física y comportamiento sedentario. También se consiguió información sobre las condiciones socioeconómicas de la familia. La opción fue el análisis de Ecuaciones de Estimaciones Generalizadas (GEE) para evaluar las asociaciones de interés. Resultados: se verificó que los estudiantes bajo intervención presentaron una disminución de 7,64 mg/dL en la media del colesterol total (p = 0,009), de 7,77 mg/dL en la media del LDLc (p = 0,003), un incremento del 18% en el consumo de legumbres (OR = 1,18; 95%IC 1,03-1,37) y del 17% en el consumo de verduras (OR = 1,17; 95%IC 1,01-1,35), comparados con aquellos que no fueron sometidos a la intervención. No hubo diferencias en los parámetros antropométricos estudiados. Conclusión: los resultados apuntaron un efecto positivo de las acciones de promoción de la alimentación adecuada y saludable en la reducción del colesterol total, LDL-c, en el aumento del consumo de vegetales y legumbres, evidenciando una vez más que el modelo de intervención fue capaz de prever y/o tratar

  4. [In Process Citation].

    PubMed

    Zhu, Jin-Zhou; Li, Chun-Xiao; Dai, Yi-Ning; Zhao, De-Jian; Fang, Zhi-Yun; Wan, Xing-Yong; Zhu, Hua-Tuo; Wang, Yu-Ming; Yu, Chao-Hui; Li, You-Ming

    2016-01-01

    Introducción: la betatrofina es una novedosa adipoquina que provoca la proliferación de células β pancreáticas e interviene en el metabolismo de los lípidos. Objetivos: el propósito de este estudio es evaluar el papel de la betatrofina en el síndrome metabólico. Método: se llevó a cabo un estudio hospitalario de casos y controles según sexo y edad. El nivel de betatrofina en suero fue evaluado mediante ensayo por inmunoabsorción ligado a enzimas. Se midieron las concentraciones en suero de 12 adipoquinas para evaluar las asociaciones con la betatrofina usando los kits comerciales Adipokine Magnetic Bead Panel. Los análisis estadísticos incluyeron correlación bivariada, análisis de curva ROC y análisis de regresión lineal multivariable. Resultados: el nivel de betatrofina en suero fue más elevado en pacientes con síndrome metabólico (997,36 ± 475,92 pg/ml, p = 0,001) que en los controles (735,35 ± 526,51 pg/ml). Frente al tercil más bajo, el tercil más alto del nivel de betatrofina mostró una asociación con mayor riesgo de síndrome metabólico (odds ratio ajustado = 3,521, intervalo de confianza [IC] 95% [1,191-10,413], p = 0,023). Se desarrolló la curva ROC de betatrofina para pronosticar la presencia de síndrome metabólico (área bajo la curva ROC = 0,682 [95% IC, 0,597-0,767], p < 0,001). Además, la betatrofina mostró correlación con distintos parámetros, como edad (r = 0,286, p < 0,001), índice de masa corporal (r = 0,160, p = 0,046), índice cintura-cadera (r = 0,241, p = 0,002), lipoproteína de alta densidad (r = -0,167, p = 0,037), lipoproteína de baja densidad (r = -0,195, p = 0,015), glucosa plasmática en ayunas (r = 0,266, p = 0,001), hemoglobina A1C (r = 0,314, p < 0,001), índice de resistencia a la insulina mediante HOMA (r = 0,272, p = 0,001) y diversas adipoquinas, entre ellas resistina (r = 0,571, p < 0,001), interleucina-8 (r = 0,435, p < 0,001), factor de necrosis tumoral alfa (r = 0,295, p = 0,011) y

  5. [Registry of myocardial infarction in a tertiary hospital of the Instituto Mexicano del Seguro Social].

    PubMed

    González-Pliego, José Angel; Gudiño-Amezcua, Diego Armando; Celis, Alfredo; Gutiérrez-Díaz, Gonzalo Israel

    2014-01-01

    Introducción: dado que el pronóstico de infarto del miocardio con elevación del segmento ST (IMCEST) depende de su manejo inmediato y de las medidas de prevención secundaria, el no seguir las recomendaciones actuales impide mejorar las expectativas de la población afectada por este padecimiento. El objetivo es describir el perfil clínico-epidemiológico y el proceso de atención del IMCEST en un hospital de tercer nivel. Métodos: se analiza la información clínica, la estratificación de riesgo, la terapia de revascularización y los hábitos de prescripción al egreso de los casos con IMCEST atendidos en un año. Resultados: se incluyeron 246 pacientes con edad promedio de 61 años; el 76 % fueron varones. La mayoría (37.3 %) de IMCEST ocurrió entre los 60 y los 69 años. El sedentarismo fue el factor de riesgo predominante. El 81.7 % de los casos tuvo score TIMI de riesgo bajo. El 35 % tuvo isquemia/viabilidad y en todos los cateterizados se demostraron obstrucciones coronarias. El 76 % se revascularizó con stent, principalmente farmacológico (77.5 %). Al egreso más del 90 % de los casos recibió estatina y antiplaquetarios, mientras otras drogas se prescribieron al 64-82 % de los casos. Conclusiones: el IMCEST predomina en hombres sedentarios de la séptima década. Estratificar el riesgo, buscar isquemia/viabilidad residual y revascularizar con stent farmacológico son prácticas comunes; el cumplimiento de recomendaciones basadas en la evidencia es mejor que en el pasado, pero todavía no es óptimo.

  6. [Fructose consumption and its health implications; fructose malabsorption and nonalcoholic fatty liver disease].

    PubMed

    Riveros, María Jesús; Parada, Alejandra; Pettinelli, Paulina

    2014-03-01

    La ingesta de fructosa se ha incrementado considerablemente en los últimos años, especialmente bajo la forma de jarabe de maíz alto en fructosa, debido a su gran poder edulcorante. Diversos estudios, han asociado su elevado consumo con alteraciones metabólicas, hígado graso no alcohólico y malabsorción de fructosa, entre otras patologías. Esta revisión tiene como objetivo actualizar acerca del efecto de la alta ingesta de fructosa en el hígado e intestino, asociada principalmente a alimentos procesados con fructosa agregada. Métodos: Para la búsqueda bibliográfica se utilizaron las bases de datos de Pubmed, Scopus y Scielo, seleccionando aquellos artículos publicados después del año 2000 y resultantes de las palabras claves “fructose intake, high fructose corn syrup, nonalcoholic fatty liver and fructose, fructose malabsorption, fructose intolerance/metabolism”. Resultados: La búsqueda arrojó 735 publicaciones de las cuales 78 cumplieron con los criterios de inclusión. Conclusiones: El consumo de fructosa ha aumentado en las últimas décadas, especialmente a través de bebidas endulzadas y productos alimentarios con fructosa agregada. La alta ingesta de fructosa tiene un impacto a nivel intestinal y hepático, asociándose a patologías como hígado graso no alcohólico y malabsorción de fructosa.

  7. [Immunomodulatory role of dietary lipids in an immunosuppressed mouse model and infected with listeria monocytogenes].

    PubMed

    Cerón Rodríguez, José María; Puertollano Vacas, M Ángeles; Puertollano Vacas, M Elena; Alvarez de Cienfuegos López, Gerardo

    2014-10-01

    Introducción: La capacidad inmunomoduladora de los ácidos grasos de la dieta en situaciones de inmunosupresión puede diferir de acuerdo con el tipo de ácido graso presente. Objetivo: Analizar el efecto de diferentes tipos de dietas lipídicas, en la resistencia de animales inmunosuprimidos o no, frente a una infección experimental con Listeria monocytogenes. Métodos: Ratones Balb/c fueron divididos en cuatro grupos experimentales, según su tratamiento inmunosupresor: control (PBS), Ciclofosfamida (CPA), GK 1.5 y RB6-8C5. Cada grupo fue subdividido en cuatro subgrupos según la dieta lipídica utilizada: control con aceite de maíz 5% (BG); aceite de oliva 20% (AO); aceite de pescado 20% (AP) y aceite de girasol 20% (AG). Los animales se alimentaron durante un mes antes del tratamiento y posteriormente infectados con L. monocytogenes. Resultados: Mostramos incrementos en el número de bacterias viables en bazo e hígado, y bajos porcentajes de supervivencia en todos los grupos de ratones inmunosuprimidos y también en el grupo PBS alimentado con AP. Además, se observaron incrementos en la linfoproliferación, de bazos de ratones alimentados con AO y tratados con CPA. Discusión: La dieta AP, produce una disminución en la resistencia del hospedador en situaciones de inmunosupresión. Por el contrario, las dietas AO y AG muestran mayor eficacia en la eliminación de L. monocytogenes y mayores ventajas en animales inmunosuprimidos. El tratamiento con RB6-8C5, produce una reducción en la supervivencia de los ratones de los grupos estudiados, lo que induce a establecer que los granulocitos juegan un papel fundamental en el control de la infección.

  8. Oral physiology and quality of life in cancer patients.

    PubMed

    Pereira, Luciano J; Braga Caputo, Júnior; Midori Castelo, Paula; Francelino Andrade, Eric; Silva Marques, Leandro; Martins de Paiva, Saul; Márcia Pereira, Stela; Vicente Pereira, Cássio

    2015-05-01

    Introdución: El tratamiento del cáncer puede afectar la salud de los dientes y estructuras de apoyo, que son esenciales para el proceso de masticación, que pueden cambiar el estado nutricional del paciente. Objetivo: El objetivo de este estudio fue evaluar el impacto de los cambios fisiológicos orales sobre la calidad de vida (QoL) de los pacientes sometidos a tratamiento contra el cáncer. Metodos: Inicialmente 84 pacientes con cáncer fueron examinados y sólo los que presentan al menos 15 dientes naturales fueron seleccionados para la fisiología oral y la calidad de las pruebas de la vida. La muestra final quedó conformado por 30 pacientes. Veinte sujetos fueron seleccionados como controles emparejados por edad y sexo. Dental estado de la caries, el flujo salival, rendimiento masticatorio (MP), la ubicación del tumor, la duración de la quimioterapia y la radioterapia y lo cuestionario de La Organización Mundial de la Salud Calidad de Vida (WHOQOL-BREF) cuestionario fueron evaluados. Se utilizaron modelos de regresión lineal para probar la relación entre los dominios del WHOQOL-BREF (psicológicos relación física,, social, ambiental y de calidad de vida en general) y variables independientes bajo estudio. Resultados y Discusión: Número de dientes, MP y el flujo salival fueron menores en los pacientes de cáncer, así como para las puntuaciones obtenidas en la relación social, medio ambiente y dominios de calidad de vida general (p.

  9. Therapeutic efficacy test in malaria falciparum in Antioquia, Colombia

    PubMed Central

    Blair, Silvia; Carmona-Fonseca, Jaime; Piñeros, Juan G; Ríos, Alexandra; Álvarez, Tania; Álvarez, Gonzalo; Tobón, Alberto

    2006-01-01

    Objective Evaluate the frequency of failure of eight treatments for non-complicated malaria caused by Plasmodium falciparum in patients from Turbo (Urabá region), El Bagre and Zaragoza (Bajo Cauca region), applying the 1998 protocol of the World Health Organization (WHO). Monotherapies using chloroquine (CQ), amodiaquine (AQ), mefloquine (MQ) and sulphadoxine-pyrimethamine (SP), and combinations using chloroquine-sulphadoxine-pyrimethamine (CQ-SP), amodiaquine-sulphadoxine-pyrimethamine (AQ-SP), mefloquine-sulphadoxine-pyrimethamine (MQ-SP) and artesunate-sulphadoxine-pyrimethamine (AS-SP), were examined. Methodology A balanced experimental design with eight groups. Samples were selected based on statistical and epidemiological criteria. Patients were followed for 21 to 28 days, including seven or eight parasitological and clinical evaluations, with an active search for defaulting patients. A non-blinded evaluation of the antimalarial treatment response (early failure, late failure, adequate response) was performed. Results Initially, the loss of patients to follow-up was higher than 40%, but the immediate active search for the cases and the monetary help for transportation expenses of patients, reduced the loss to 6%. The treatment failure was: CQ 82%, AQ 30%, MQ 4%, SP 24%, CQ-SP 17%, AQ-SP 2%, MQ-S-P 0%, AS-SP 3%. Conclusion The characteristics of an optimal epidemiological monitoring system of antimalarial treatment response in Colombia are discussed. It is proposed to focus this on early failure detection, by applying a screening test every two to three years, based on a seven to 14-day follow-up. Clinical and parasitological assessment would be carried out by a general physician and a field microscopist from the local hospital, with active measures to search for defaulter patients at follow-up. PMID:16504002

  10. [MALNUTRITION BY EXCESS IN CHILDREN-ADOLESCENT AND ITS IMPACT ON THE DEVELOPMENT OF RISK CARDIOMETABOLIC AND LOW LEVELS OF PHYSICAL PERFORMANCE].

    PubMed

    Caamaño Navarrete, Felipe; Delgado Floody, Pedro; Guzmán Guzmán, Iris Paola; Jerez Mayorga, Daniel; Campos Jara, Christian; Osorio Poblete, Aldo

    2015-12-01

    Antecedentes: en Chile, el incremento de la obesidad infantil se ha transformado en una pandemia y ha llegado a ser un importante problema de salud pública. Objetivo: el propósito del estudio fue determinar la prevalencia de malnutrición por exceso de niños-adolescentes y analizar su asociación con el riesgo cardiometabólico y el rendimiento físico. Material y métodos: participaron en la investigación 342 escolares (151 mujeres y 191 hombres), que presentaban entre 11 y 16 años de edad; se evaluó índice de masa corporal (IMC), porcentaje de masa grasa (%MG), contorno de cintura (CC), razón cintura-estatura (RCE) y rendimiento físico a través de una batería de test. Resultados: el 3,2% de los niños-adolescentes presentaron bajo peso, el 48,5% normopeso, 30,9% sobrepeso y el 17,3 % obesidad. Las categorías se analizaron como la presencia o no de sobrepeso y obesidad. Se reportó una relación inversa entre el estado nutricional y el rendimiento físico. Los escolares con obesidad, en comparación con los que no la presentan, mostraron un incremento significativo en las medidas antropométricas, así como una disminución del rendimiento físico (p.

  11. [Reliability of a questionnaire to assess physical activity in normal weight adolescents and overweight].

    PubMed

    Gómez Campos, Rossana; de Arruda, Miguel; Camargo, Cristiane; Cossio Bolaños, Marco A

    2015-05-01

    Introducción: En los últimos años se ha reportado altos niveles de obesidad relacionados con bajos niveles de actividad física, lo que muestra la necesidad de su valoración como elementos de la salud y calidad de vida. Objetivo: Verificar la capacidad de reproductibilidad de un cuestionario de AF en adolescentes escolares clasificados como normopeso, con sobrepeso y con obesidad. Métodos: Se realizó un estudio descriptivo de corte transversal en 1306 adolescentes escolares (562 hombres y 744 mujeres) de tres instituciones educativas Municipales de la provincia de Talca (Chile). El rango de edad fue de 12,0 a 17,9 años. Se evaluó el peso y la estatura y se calculó el Índice de Masa Corporal. Se utilizó los puntos de corte del CDC-2000 para la clasificación en categorías nutricionales (normopeso, sobrepeso y obesidad). Se aplicó una encuesta de actividad física a los tres grupos estudiados. Resultados: Se identificaron 388 hombres y 533 mujeres con normopeso, 131 hombres y 169 mujeres con sobrepeso, 43 hombres y 42 mujeres con obesidad. En ambos sexos el alfa de Cronbach mostró altos valores de confiabilidad. En hombres (con normopeso 0,80, con sobrepeso 0,77 y con obesidad 0,83) y en mujeres (con normopeso 0,79, con sobrepeso 0,77 y con obesidad 0,76). Conclusión: El instrumento utilizado mostró alta capacidad de reproductibilidad, tanto en adolescentes normopesos, con sobrepeso y con obesidad. Estos resultados sugieren el uso cotidiano en la encuesta para valorar los patrones de AF a gran escala, independientemente del estado nutricional en la que se encuentren.

  12. [Sedentarism and physical fitness in postmenopausal women].

    PubMed

    Morales, Silvia; Gómez-Cabello, Alba; González-Agüero, Alejandro; Casajús, José Antonio; Ara, Ignacio; Vicente-Rodríguez, Germán

    2013-01-01

    Introducción: El envejecimiento es un proceso fisiológico natural asociado a diferentes cambios, entre los que se encuentra un descenso de la condición física. Objetivos: Establecer la relación entre un comportamiento sedentario (permanecer sentada =?4 horas/día) y la condición física en 457 mujeres mayores de 65 años. Metodología: La condición física se evaluó mediante 8 test (adaptados de las baterías “Senior Fitness Test” y “Eurofit Testing Battery”). Se utilizó ANOVA para analizar las diferencias entre grupos en función de las horas de sedestación y regresión logística para estudiar la asociación del comportamiento sedentario con una baja condición física, utilizando como referencia el percentil 20 de los valores normativos en España (Proyecto EXERNET). Resultados: Las mujeres sedentarias obtuvieron valores más bajos en las pruebas de equilibrio, fuerza de piernas y brazos, flexibilidad de brazos, velocidad y resistencia (p < 0,05). Además, aquellas mujeres que permanecían sentadas =?4 horas/día tenían mayor probabilidad de tener baja condición física en la mayoría de las pruebas citadas anteriormente, independientemente de las horas dedicadas a caminar (p < 0,05). Conclusión: Permanecer mucho tiempo sentada influye negativamente sobre la condición física de las mujeres postmenopáusicas independientemente del tiempo que caminen.

  13. [Control of epilepsy in adult patients with tuberous sclerosis].

    PubMed

    Gallardo-Tur, Alejandro; García-Martín, Guillermina; Chamorro-Muñoz, María Isabel; Romero-Godoy, Jorge; Romero-Acebal, Manuel

    2013-06-01

    Introduccion. La esclerosis tuberosa es una enfermedad genetica cuyas manifestaciones principales son la formacion de tumores neuroectodermicos, que asocia epilepsia secundaria muy frecuentemente. Objetivo. Describir el perfil epileptico, el control, la frecuencia de crisis y la efectividad del tratamiento en pacientes adultos con esclerosis tuberosa. Pacientes y metodos. Estudio descriptivo en el que se han incluido pacientes adultos (mayores de 14 anos) con diagnostico confirmado de esclerosis tuberosa. Se ha analizado la frecuencia y tipos de crisis. Se ha realizado un estudio y contabilizacion de los diferentes farmacos antiepilepticos en cada paciente, la frecuencia de uso de cada principio activo y un estudio comparativo entre control de crisis y tipo de terapia. Resultados. De 19 adultos estudiados, tuvieron crisis epilepticas 16 (84%). Presentaron control de crisis completo, crisis esporadicas y crisis frecuentes el 44%, 25% y 31%, respectivamente. Hubo frecuencia de crisis focales, generalizadas y ambas en el 38%, 6% y 25%, respectivamente. Estaban en tratamiento con farmacos antiepilepticos en monoterapia, biterapia y triterapia el 38%, 44% y 19%, respectivamente. El mas consumido globalmente fue el levetiracetam, seguido de la carbamacepina y el acido valproico. En monoterapia, el mas frecuente fue la carbamacepina, con mayor proporcion de control completo. Conclusiones. La epilepsia en la esclerosis tuberosa es relativamente benigna, y se consigue un aceptable control en la mayoria de casos con un numero de antiepilepticos acorde con lo aconsejado en las guias de tratamiento. Se observa estabilidad de lesiones, y no hay malignizacion en nuestra serie. El bajo numero de la muestra limita el estudio, pero se observan proporciones similares de efectividad del tratamiento respecto a otra serie publicada.

  14. [Endovascular treatment of spinal dorsal intradural arteriovenous fistulas].

    PubMed

    Santos-Franco, Jorge Arturo; Collado-Arce, María Griselda Lizbeth; Dávila-Romero, Julio César; Saavedra-Andrade, Rafael; Sandoval-Balanzario, Miguel Antonio

    2015-01-01

    Introducción: las fístulas arteriovenosas intradurales dorsales espinales (FAVIDE) son lesiones poco frecuentes y complejas que son subdiagnósticadas y condicionan discapacidad. El objetivo es presentar nuestra experiencia en el manejo endovascular. Métodos: estudio ambispectivo de pacientes con FAVIDE, tratados mediante terapia endovascular (TEV) con n-butil-cianoacrilato en el periodo de 2007 a 2013. Resultados: se incluyeron 15 pacientes con edad media de 37 años. En 12 casos la presentación fue progresiva e insidiosa en un lapso de entre 6 meses y un año, mientras que 3 presentaron hemorragia. La lesión tuvo localización torácica en 73 % de los casos, lumbar en 20 % y cervical en 7 %. Previo al tratamiento observamos discapacidad de grados 5 y 4 en 73 %, y 67 % tenían alteraciones de la micción de grado 3. Como complicaciones, solo una paciente tuvo deterioro del estado de alerta transitorio 6 horas después del procedimiento. Se encontró una mejoría hacia los grados 1 y 2 de discapacidad, a las 48 horas, 3 y 6 meses, de 53 %, 73 % y 87 %, respectivamente. Conclusiones: con la TEV se tiene un tiempo quirúrgico corto, el volumen de hemorragia es bajo y la estancia hospitalaria es corta, respecto de otras técnicas quirúrgicas. La TEV es un procedimiento seguro y con efectividad significativa en el tratamiento de FAVIDE. Esta es la primera serie de casos tratados con TEV en México.

  15. [Urgent stroke care in hospitals with a stroke unit. Quick Project].

    PubMed

    Masjuán, Jaime; Álvarez-Sabín, José; Arias-Rivas, Susana; Blanco, Miguel; de Felipe, Alicia; Escudero-Martínez, Irene; Fuentes, Blanca; Gállego-Culleré, Jaime; Moniche-Álvarez, Francisco; Muñoz, Lucía; Pérez de la Ossa-Herrero, Natalia; Sahuquillo, Patricia; Santamarina, Estevo; Sanz, Borja; Tembl, José I; Zandio, Beatriz

    2016-04-01

    Introduccion. El ictus es una emergencia medica dependiente del tiempo. La rapidez en su reconocimiento y en la atencion que reciben los pacientes es clave en el pronostico. Objetivos. Analizar los tiempos de actuacion medica, evaluar posibles areas de mejora y estudiar la dotacion de recursos de los centros. Pacientes y metodos. Registro prospectivo de pacientes atendidos en ocho unidades de ictus experimentadas españolas con sospecha de ictus y activacion del codigo ictus. Se recogieron los tiempos inicio-puerta, puerta-tomografia computarizada (TC), puerta-aguja, TC-aguja e inicio-aguja. Tambien se recogieron el metodo de trasporte al hospital, el tipo de ictus y las terapias de reperfusion. En cuanto a la dotacion estructural de los centros, se recogieron la ratio de enfermeria, la monitorizacion de camas, la disponibilidad de TC multimodal y resonancia magnetica, y la realizacion de cursos de informacion o formacion. Resultados. Se incluyeron 197 pacientes, de los cuales fueron validos 181 (151 infartos y 30 hemorragias cerebrales). Las medianas (p25-p75) en minutos fueron: inicio-puerta, 104 (70-188); puerta-TC, 27 (19-41); TC-aguja, 30 (21-43); puerta-aguja, 64 (49-83); e inicio-aguja, 156 (129-202). Se aplicaron terapias de reperfusion en 68 pacientes (el 45% de los infartos cerebrales), de los cuales el 81% fueron trombolisis intravenosas; el 7%, tratamientos endovasculares; y el 12%, una combinacion de ambos. Los recursos de los centros estuvieron de acuerdo con lo recomendado por las guias clinicas. Hubo un bajo porcentaje de pacientes estudiados con resonancia magnetica. Conclusion. El porcentaje de pacientes tratados con trombolisis fue muy elevado y los tiempos de los circuitos intrahospitalarios, aunque buenos, tienen margen de mejora.

  16. Prevalence and determinants of the dual burden of malnutrition at the household level in Puna and Quebrada of Humahuaca, Jujuy, Argentina.

    PubMed

    Bassete, M N; Romaguera, D; Giménez, M A; Lobo, M O; Samman, N C

    2014-02-01

    El objetivo del presente estudio fue identificar los hogares en los que coexisten el sobrepeso y bajo peso (doble carga de malnutrición) y explorar los factores que podrían contribuir a la doble carga de malnutrición en los hogares de esta población. Después de aplicar los criterios de exclusión, se incluyeron 136 hogares. Las madres fueron clasificadas como de peso normal o con sobrepeso/ obesidad basado en puntos de corte del índice de masa corporal (IMC), los niños y adolescentes fueron clasificados según z–score de la talla para la edad, si tenían o no retraso en el crecimiento (Stunted). Los hogares con una madre obesa y niños o adolescentes con retraso en el crecimiento fueron clasificados como hogares de doble carga. La prevalencia de hogares con doble carga fue del 12 %. En comparación con los otros hogares, en los hogares con doble carga de malnutrición habitan un mayor número de personas en la casa, y el nivel de educación del jefe de familia fue menor. Las personas que viven en hogares de doble carga mostraron ingestas de energía global más bajas y eran más propensos a tener una ingesta insuficiente de calcio y hierro. Una de las principales causas de la doble carga de malnutrición observada en esta comunidad podría ser la transición nutricional. Los resultados presentados aquí indican la necesidad de considerar a los programas que se centran en un solo tipo de problema nutricional y que en realidad podrían exacerbar el otro.

  17. [EVALUATION OF THE BODY ADIPOSITY INDEX IN PREDICTING PERCENTAGE BODY FAT AMONG COLOMBIAN ADULTS].

    PubMed

    González-Ruíz, Katherine; Correa-Bautista, Jorge Enrique; Ramírez-Vélez, Robinson

    2015-07-01

    Objetivo: el índice de adiposidad corporal (IAC) es un sencillo y nuevo método de predicción del porcentaje de grasa corporal (%GC) a través de una simple ecuación que incluye la circunferencia de cadera y la estatura. Hasta la fecha, pocos estudios han evaluado el IAC en la determinación el exceso de grasa en la población colombiana. El objetivo de este estudio fue evaluar la utilidad del IAC como predictor del %GC en adultos de Colombia. Métodos: estudio transversal en 204 hombres del sector educativo de Bogotá, Colombia. Se estimó el IAC con la ecuación de Bergman et al. [(circunferencia de cadera, en cm)/((estatura, en m)1,5 )-18)]. El %GC se determinó a través de bioimpedancia eléctrica tetrapolar (BIA) como la medida de referencia de la adiposidad. Se utilizó el análisis de Bland-Altman para evaluar el grado de acuerdo entre ambos métodos, IAC y BIA, y se evaluaron las relaciones con otras medidas antropométricas mediante el coeficiente de correlación de Pearson. Resultados: en la población general, el IAC sobreestima el %GC (diferencia de medias: 12,5% [IC95% = -4,04% a -21.02%]), en especial en sujetos con niveles bajos de adiposidad (diferencia de medias: 10,2 ± 3,3). Tras ajustar por edad, el IAC muestra correlaciones significativas con el IMC (r = 0,480), la relación cintura-estatura (r = 0,557) y el %GC por BIA (r = 0,777), p.

  18. [A better self-perception of physical fitness is associated with lower prevalence of metabolic syndrome and its components among university students].

    PubMed

    Fonseca-Camacho, Deivy Fredery; Hernández-Fonseca, John Manuel; González-Ruíz, Katherine; Tordecilla-Sanders, Alejandra; Ramírez-Vélez, Robinson

    2014-12-17

    Objetivo: Evaluar si la auto-percepción de la condición física (CF) se relaciona con la frecuencia y componentes del síndrome metabólico (SM) en una muestra de estudiantes universitarios de Bogotá, Colombia. Método: Un total de 493 varones (edad 28,5±11,5 años) universitarios sin enfermedad cardiovascular previa, completaron el cuestionario de auto-reporte de la CF “The International FItness Scale” (IFIS). La identificación de los componentes relacionados al SM se establecieron según los criterios del “International Diabetes Federation” (IDF) y el “National Colesterol Education Program’s Adult Treatment Panel III” (NCEP: ATP-III). La masa grasa (MG), el porcentaje de grasa (%G), la masa libre de grasa (MLG) y el índice de masa grasa (IMG), se estimaron con equipo de impedancia bioeléctrica segmentada. Resultados: El 23% de los participantes presentaron SM. La obesidad abdominal (33%) fue el factor más prevalente, seguido del c-HDL bajo (31%). Los demás componentes asociados a la presencia de SM fueron hipercolesterolemia (60%), c-LDL elevado (32%) e hipertrigliceridemia (19%). Los sujetos que acusaron como “bueno/muy bueno” en el auto-reporte de fitness cardiorrespiratorio/ muscular, presentaron promedios más saludables en la tensión arterial, MLG, IMG y triglicéridos (p.

  19. [Differences in magnitude of nutritional status in Chilean school children according to CDC and WHO 2005-2008 reference].

    PubMed

    Vásquez, Fabián; Cerda Rioseco, Ricardo; Andrade, Margarita; Morales, Gladys; Gálvez, Patricia; Orellana, Yasna; Leyton, Bárbara

    2013-01-01

    Introducción: Es necesario realizar nuevas discusiones respecto a la magnitud de los problemas nutricionales diagnosticados, al usar CDC u OMS, frente a la existencia de nuevas definiciones biológicas o estadísticas de obesidad. Objetivo: Comparar la evolución de la prevalencia de estado nutricional en escolares de primero básico, desde el 2013 2005 al 2008, según CDC y OMS. Métodos: Cohorte retrospectiva, de 140.265 escolares de ambos sexos de primero básico, evaluados entre 2005- 2008, cuyos datos antropométricos (peso y talla), se obtuvieron del sistema anual de registro del estado nutricional escolar. Para clasificar el estado nutricional, se utilizaron los patrones CDC y OMS. Resultados: Los promedios de IMC fueron levemente diferentes y menores en la niñas que en los niños, en 2005 y 2006. Durante el 2007 y 2008 el promedio de IMC en las niñas alcanzó la cifra observada en los varones. Hubo mayor prevalencia de bajo peso según OMS (p=0,03), con una tendencia a la disminución en los 2013s posteriores. La prevalencia de normalidad fue mayor según el criterio CDC, con una reducción entre el 2005 y 2007 y un incremento 2008 (p<0,001). Hubo una menor prevalencia de sobrepeso según el criterio CDC (p<0,001), con aumento entre el 2005 y 2007, tanto CDC como OMS. La prevalencia de obesidad fue menor según el criterio OMS, no encontrándose diferencia estadísticamente significativa al comparar con el patrón CDC. Conclusiones: Al comparar ambos patrones, CDC tiende a sobreestimar la normalidad y subestimar el sobrepeso, mientras que en obesidad no se encontraron diferencias significativas.

  20. La formación de la Nube de Oort y el entorno galáctico primitivo

    NASA Astrophysics Data System (ADS)

    Fernández, J. A.

    Se analizan las condiciones de formación de la nube de Oort en el medio galáctico primitivo, bajo la suposición de que los objetos que alcanzaron la nube fueron planetesimales residuales eyectados por los planetas gigantes durante las etapas finales de su acreción. Los objetos que adquieren órbitas cuasiparabólicas están sujetos a las perturbaciones de estrellas vecinas y al potencial del disco galáctico, las que desacoplan sus perihelios de la región planetaria, dando a los objetos una larga estabilidad dinámica. Se demuestra que un entorno galáctico como el presente pudo, sin embargo, no ser suficiente para formar un reservorio cometario con una vida dinámica comparable a la vida del sistema solar. La existencia de la nube de Oort después de 4600 millones de años es, pues, una fuerte indicación de que el sistema solar se formó en un entorno galáctico mucho mas denso que el presente, tal vez en una nube molecular y/o un cúmulo abierto, que es el modo de producción de la mayoría de las estrellas. Se encuentra que un campo perturbador externo mas intenso, producto de un entorno galáctico mas denso, sería capaz de formar una nube de Oort mas compacta, con un radio del orden de 103- 104 UA. El campo externo mas intenso cesó de actuar una vez que la nube molecular y/o el cúmulo abierto se disiparon, previniendo entonces que ese mismo campo externo disolviera el reservorio cometario.

  1. Efficacy of social support on metabolic syndrome among low income rural women in Chiapas, México.

    PubMed

    Bezares-Sarmiento, Vidalma del Rosario; Bacardí-Gascón, Montserrat; Márquez-Rosa, Sara; Molinero-González, Olga; Estrada-Grimaldo, Martha; Jiménez-Cruz, Arturo

    2013-01-01

    Introducción: El propósito de este estudio fue valorar una intervención de soporte social entre mujeres rurales de Chiapas, sobre los cambios en el estilo de vida, el autoconcepto, y el síndrome metabólico (MS). Métodos: Se realizó una muestra de conveniencia entre todas la mayores de 16 años de una población rural marginada del centro de Chiapas. Se utilizaron dos cuestionarios. Uno sobre el auto-concepto de salud y el otro sobre el perfil de estilos saludables. Los componentes del MS se valoraron de acuerdo a los criterios de la Federación Internacional de Diabetes. La intervención se realizó durante un período de tres meses y se dividió en 13 sesiones que incluían soporte social (SS) y educación nutricional (EN). Resultados: Cumplieron con los criterios de inclusión, 586 mujeres. Al inicio del estudio 47% tenían MS; obesidad abdominal, 69%; altos niveles de glucosa, 27%; de triglicéridos, 56%; de presión arterial sistólica, 17%; de presión arterial diastólica, 15%; y bajos niveles de colesterol- HDL, 55%. Después de la intervención 38% presentaron MS y se observó una reducción de todos los componentes del MS. Al final del estudio se observaron cambios significativos en AF5, PETS-1 y algunos componentes del SM. Conclusiones: Después de una intervención de SS y EN, se observaron cambios significativos en varias dimensiones del AF5 y del PETS-1, así como en SM y todos los componentes del SM.

  2. [Prognostic implications of folliculo-stellate cells in pituitary adenomas: relationship with tumoral behavior].

    PubMed

    Tortosa, F; Pires, M; Ortiz, S

    2016-10-01

    Introduccion. A pesar del progreso en la comprension de su patogenia, no se ha encontrado ningun marcador predictivo independiente del comportamiento agresivo de los adenomas hipofisarios que facilite el tratamiento y seguimiento de pacientes afectados. Objetivo. Analizar la expresion de celulas foliculo-estrelladas, mediante inmunomarcacion con proteina S-100, en una serie de pacientes con adenomas hipofisarios seguidos durante al menos siete años. Pacientes y metodos. Estudio retrospectivo de 51 pacientes diagnosticados de adenoma hipofisario entre 2006 y 2008, segun los criterios vigentes de la Organizacion Mundial de la Salud. Se evaluo inmunohistoquimicamente la expresion de S-100 en celulas foliculo-estrelladas, y se correlaciono con parametros clinicorradiologicos e histopatologicos del tumor y la progresion/recurrencia postoperatoria. Resultados. De 51 tumores, 40 se clasificaron como adenomas hipofisarios tipicos y 11 como atipicos. La mayoria de los tipicos mostro celulas foliculo-estrelladas positivas para S-100 (media: 3,93%); los atipicos tenian pocas o ninguna celula S-100 positivas (media: 0,83%). No hubo diferencias significativas en la expresion de S-100 con respecto a la edad o sexo del paciente, tamaño, invasividad o recidiva tumoral posquirurgica. Conclusiones. En el grupo de estudio, a excepcion de los adenomas no funcionantes inmunopositivos para prolactina, con la media mas baja y mas alta de todos los subtipos en ambos grupos (tipicos, 0,25%, frente a atipicos, 9,24%; p = 0,0028), el factor predictivo de agresividad tumoral para los adenomas hipofisarios no esta representado por un bajo valor de S-100 en las celulas foliculo-estrelladas, lo que no permite seleccionar a pacientes para un tratamiento postoperatorio intensivo.

  3. [PREVALENCE OF THINNESS, OVERWEIGHT AND OBESITY AMONG 4-TO-6-YEAR-OLD SPANISH SCHOOLCHILDREN IN 2013; SITUATION IN THE EUROPEAN CONTEXT].

    PubMed

    González García, Alberto; Álvarez Bueno, Celia; Lucas de la Cruz, Lidia; Sánchez López, Mairena; Solera Martínez, Montserrat; Díez Fernández, Ana; Martínez Vizcaíno, Vicente

    2015-10-01

    Introducción y objetivos: tanto el exceso de peso como la delgadez se relacionan con diversos problemas de salud que pueden continuar hasta la edad adulta. Los objetivos de este estudio fueron estimar la prevalencia de delgadez, sobrepeso y obesidad en escolares de 4-6 años de las provincias de Cuenca y Ciudad Real (España), mediante criterios del Grupo Internacional de Trabajo sobre Obesidad y de la Organización Mundial de la Salud, y comparar estas cifras con otros estudios europeos. Métodos: estudio observacional-transversal que incluyó a 1.585 escolares realizado en septiembre de 2013. Las mediciones de peso y talla fueron realizadas por enfermeras entrenadas y mediante procedimientos estandarizados. El estatus ponderal se definió según los criterios del Grupo Internacional de Trabajo sobre Obesidad y la Organización Mundial de la Salud. Resultados: según criterios del Grupo Internacional de Trabajo sobre Obesidad, la prevalencia de delgadez, sobrepeso y obesidad fue del 20,51%, 11,84% y 8,58%, respectivamente; y del 3,97%, 13,92% y 10,79% cuando se utilizaron los criterios de la Organización Mundial de la Salud. No se encontraron diferencias estadísticamente significativas por sexo ni provincia para ninguna categoría de estatus ponderal. Para ambos criterios, la prevalencia de delgadez fue menor a medida que aumentaba la edad, mientras que la prevalencia de sobrepeso/obesidad fue mayor. Conclusiones: la prevalencia de exceso de peso podría haber tocado techo en España, aunque continúa siendo un importante problema de salud pública. El aumento de la prevalencia de bajo peso debería ocupar un lugar relevante en las intervenciones de salud pública.

  4. Clinical and Demographic Characteristics of Binge Drinkers Associated with Lack of Efficacy of Brief Intervention and Medical Advice.

    PubMed

    Rubio, Gabriel; López-Rodríguez, Juan A; Zuluaga, Pilar; Ponce, Guillermo; Martínez-Gras, Isabel; Jiménez-Arriero, Miguel Ángel

    2015-06-17

    La Intervención Breve (IB) y el Consejo Médico simple (CM) son intervenciones psicoterapéuticas usadas para el tratamiento del consumo de alcohol por atracones en Atención Primaria. A pesar de la frecuencia de este patrón de abuso en Europa y en los Estados Unidos, ningún estudio ha evaluado las características de los sujetos que no responden a esas dos técnicas. Objetivo. Determinar las características demográficas y clínicas de los bebedores por atracones en los que la IB y el CM no son efectivos para la reducción del consumo perjudicial de alcohol. Métodos. Se trata de un análisis secundario de los datos obtenidos en un ensayo aleatorizado de intervención breve en alcohol con un período de seguimiento de 12 meses. Un total de 674 sujetos (89%) participaron durante todo el estudio hasta el final. La variable principal fue el cambio en el uso perjudicial de alcohol tras 12 meses de seguimiento. Resultados. Para ambos grupos de tratamiento las variables que predecían la continuidad en el consumo perjudicial tras el seguimiento eran: bajo nivel educativo, ser jóvenes, el número de cigarrillos fumados, la historia familiar de alcoholismo y la gravedad del consumo de alcohol basalmente. Conclusiones. Las características clínicas y sociodemográficas de los sujetos con un patrón de consumo de alcohol por atracones atendidos en Atención primaria influyen en el pronóstico de las Intervenciones breves y del Consejo Médico.

  5. HYPERTRIGLYCERIDEMIC WAIST PHENOTYPE AND CARDIOMETABOLIC ALTERATIONS IN BRAZILIAN ADULTS.

    PubMed

    Cabral Rocha, Anna Ligia; Feliciano Pereira, Patricia; Cristine Pessoa, Milene; Gonçalves Alfenas, Rita de Cassia; Segheto, Wellington; da Silva, Danielle Cristina Guimarães; Pacheco Andrade, Marcio; Zarbato Longo, Giana

    2015-09-01

    Objetivos: evaluar la prevalencia de alteraciones cardiometabolicas segun el fenotipo cintura hipertrigliceridemica (CH) en adultos brasilenos. Métodos: estudio transversal, de base poblacional, con 976 (n = 533 mujeres) individuos de 20 a 59 anos. El CH fue definido por un aumento en las concentraciones de trigliceridos y en la circunferencia de la cintura (CC). Todos los analisis fueron ajustados por el efecto del diseno del estudio y ponderados por genero, edad y escolaridad. Fue realizado un análisis descriptivo de promedio y presentados sus respectivos intervalos de confianza (IC 95%). La prevalencia de las alteraciones cardiometabolicas segun la presencia o no del fenotipo CH y segun el sexo fue calculada y comparada a traves del test chi-cuadrado de Pearson. El nivel de significancia estadistica adoptado fue de 0,05. Se estimo la probabilidad de riesgo de evento coronario en 10 anos, a partir del score de Framinghan a traves del grafico de densidad de Kernel. Resultados: la prevalencia del fenotipo CH en la muestra fue de 17,32% (IC 95% 13,54-21,89), no se observo diferencia entre sexos. Se observaron mayores promedios para todos los factores de riesgo cardiometabolico analizados en aquellos con CH. Solo Se verificaron menores valores medianos para el HDL en este grupo. Los individuos con CH presentaban mayor probabilidad de evolucionar hacia un evento cardiovascular en 10 anos que aquellos sin el fenotipo. Conclusión: el fenotipo CH constituye un importante marcador precoz del riesgo cardiovascular. Su utilizacion en la practica clinica debe ser incentivada, ya que se trata de una herramienta sencilla y de bajo coste.

  6. [ANTHROPOMETRIC INDICATORS AND CARDIOMETABOLIC EVENTS AMONG SCHOOL-AGED CHILDREN FROM SONORA, MEXICO].

    PubMed

    Peralta Peña, Sandra Lidia; Reséndiz González, Eunice; Rubí Vargas, María; Terrazas Medina, Efraín Alonso; Cupul Uicab, Lea Aurora

    2015-10-01

    Introducción: la obesidad durante la niñez es predictiva de obesidad en la adultez y se asocia a eventos adversos para la salud observables desde etapas tempranas; sin embargo, la evaluación conjunta de obesidad y eventos adversos en los menores no es parte de la atención médica habitual. Objetivos: evaluar la asociación de sobrepeso y obesidad, obesidad abdominal y exceso de grasa corporal con la presión arterial sistólica [PAS] y diastólica [PAD], y el perfil de lípidos y glucosa; e identificar el mejor indicador antropométrico de dichos eventos. Material y métodos: estudio transversal en 412 escolares a quienes se les determinó la presencia de sobrepeso y obesidad, obesidad abdominal y exceso de grasa corporal. Los niveles de colesterol total, triglicéridos, lipoproteínas de alta y baja densidad y glucosa se determinaron en una submuestra (n = 133). Las asociaciones se evaluaron con modelos de regresión lineal y logística ajustados. Resultados: el 33% de los participantes tuvieron sobrepeso u obesidad. El sobrepeso, la obesidad, la obesidad abdominal y el exceso de grasa corporal se asociaron con un incremento de PAS y PAD, y con un perfil de lípidos y glucosa que representan riesgos para la salud. El sobrepeso y la obesidad fueron los mejores predictores de dichos eventos. Conclusiones: en nuestra población, la obesidad se asoció con mayor posibilidad de presentar eventos adversos para la salud como PA elevada, niveles de lípidos y glucosa altos. La obesidad puede ser determinada con el IMC, que es un índice de bajo coste, no invasivo y de fácil implementación.

  7. Seasonal changes in fish assemblage structure at a shallow seamount in the Gulf of California

    PubMed Central

    Klimley, A. Peter; Muhlia-Melo, Arturo; Morgan, Steven G.

    2016-01-01

    Seamounts have generally been identified as locations that can promote elevated productivity, biomass and predator biodiversity. These properties attract seamount-associated fisheries where elevated harvests can be obtained relative to surrounding areas. There exists large variation in the geological and oceanographic environment among the thousands of locations that fall within the broad definition of seamount. Global seamount surveys have revealed that not all seamounts are hotspots of biodiversity, and there remains a strong need to understand the mechanisms that underlie variation in species richness observed. We examined the process of fish species assembly at El Bajo Espiritu Santo (EBES) seamount in the Gulf of California over a five-year study period. To effectively quantify the relative abundance of fast-moving and schooling fishes in a ‘blue water’ habitat, we developed a simplified underwater visual census (UVC) methodology and analysis framework suitable for this setting and applicable to future studies in similar environments. We found correlations between seasonally changing community structure and variability in oceanographic conditions. Individual species responses to thermal habitat at EBES revealed three distinct assemblages, a ‘fall assemblage’ tracking warmer overall temperature, a ‘spring assemblage’ correlated with cooler temperature, and a ‘year-round assemblage’ with no significant response to temperature. Species richness was greatest in spring, when cool and warm water masses stratified the water column and a greater number of species from all three assemblages co-occurred. We discuss our findings in the context of potential mechanisms that could account for predator biodiversity at shallow seamounts. PMID:27651985

  8. [Methods to obtain platelet-rich plasma and osteoinductive therapeutic use].

    PubMed

    Moreno, Raquel; Gaspar Carreño, Marisa; Jiménez Torres, José; Alonso Herreros, José María; Villimar, Ana; López Sánchez, Piedad

    2015-05-01

    Introduccion: El Plasma Rico en Plaquetas (PRP) es un plasma autólogo con una cifra de plaquetas superior a la del plasma basal, por haber sido sometido a algún proceso de extracción y concentración. El empleo del PRP como osteoinductor es conflictivo dado que, no existen estudios clínicos rigurosos que permita extraer conclusiones firmes respecto a su utilidad. Objetivo: Proporcionar información sobre las técnicas de obtención del PRP, las consideraciones legales sobre su obtención y empleo, el mecanismo de acción molecular, así como la evidencia disponible sobre su seguridad y tolerancia. Resultado: El PRP se obtiene de forma manual, mediante “técnica abierta”, o mediante kits desechables con “técnica cerrada”, siendo estos últimos productos sanitarios clasificados como IIa. La Agencia Española de Medicamentos y Productos Sanitarios (AEMPS) considera el PRP como medicamento, estableciendo unos requisitos mínimos para garantizar su seguridad, trazabilidad, farmacovigiliancia e información. El PRP, por su elevado contenido en factores de crecimiento, reúne cualidades para ser un potente papel osteoinductor, capaz de acelerar la consolidación de fracturas o de osteointegrar rápida y eficientemente distintos tipos de implantes óseos. La tolerancia a la infiltración es generalmente buena, aunque hay que tener en cuenta su elevado potencial angiogénico. Conclusiones: El PRP, dadas las características de producción y aplicación, es considerado por la AEMPS como un medicamento de dispensación bajo prescripción médica restringida, por lo que los servicios de farmacia hospitalaria deberían, cuando menos, supervisar su gestión y manipulación.

  9. [Tropical spastic paraparesis in a non tropical region].

    PubMed

    Pias-Peleteiro, L; Pias-Peleteiro, J M; Arias, M

    2015-10-16

    Introduccion. El virus linfotropo humano de celulas T tipo 1 (HTLV-1) es el agente causal de la paraparesia espastica tropical. Su prevalencia, elevada en determinadas areas tropicales, es baja en Europa y Norteamerica. Casos clinicos. Se describen dos casos de paraparesia espastica tropical en varones naturales y residentes en Galicia. Se realizaron estudios analiticos en la sangre y el liquido cefalorraquideo (LCR), examenes neurofisiologicos y resonancia magnetica craneal y medular. En ambos pacientes, la presentacion clinica fue la de una mielopatia cronica, con cuadro torpido y progresivo que evoluciono a paraparesia espastica. Un paciente desarrollo uveitis antes de la clinica neurologica. En los dos casos, el estudio del LCR demostro leve pleocitosis linfoide, ligera hiperproteinorraquia, bandas oligoclonales negativas y anticuerpos anti-HTLV-1 positivos. La reaccion en cadena de la polimerasa par