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Sample records for pikas ochotona princeps

  1. Behavioral ecology of American Pikas (Ochotona princeps) at Mono Craters, California: living on the edge

    Treesearch

    Andrew T. Smith; John D. Nagy; Connie Millar

    2016-01-01

    The behavioral ecology of the American pika (Ochotona princeps) was investigated at a relatively hot south-facing, low-elevation site in the Mono Craters, California, a habitat quite different from the upper montane regions more typically inhabited by this species and where most prior investigations have been conducted. Mono Craters pikas exhibited...

  2. New records of marginal locations for American pika (Ochotona princeps) in the Western Great Basin

    Treesearch

    Constance I. Millar; Robert D. Westfall; Diane L. Delany

    2013-01-01

    We describe 46 new site records documenting occupancy by American pika (Ochotona princeps) at 21 locations from 8 mountain regions in the western Great Basin, California, and Nevada. These locations comprise a subset of sites selected from regional surveys to represent marginal, isolated, or otherwise atypical pika locations, and to provide...

  3. Plastic pikas: Behavioural flexibility in low-elevation pikas (Ochotona princeps)

    USGS Publications Warehouse

    Varner, Johanna; Horns, Joshua J.; Lambert, Mallory S.; Westberg, Elizabeth; Ruff, James; Wolfenberger, Katelyn; Beever, Erik; Dearing, M. Denise

    2016-01-01

    Behaviour is an important mechanism for accommodating rapid environmental changes. Understanding a species’ capacity for behavioural plasticity is therefore a key, but understudied, aspect of developing tractable conservation and management plans under climate-change scenarios. Here, we quantified behavioural differences between American pikas (Ochotona princeps) living in an atypical, low-elevation habitat versus those living in a more-typical, alpine habitat. With respect to foraging strategy, low-elevation pikas spent more time consuming vegetation and less time caching food for winter, compared to high-elevation pikas. Low-elevation pikas were also far more likely to be detected in forested microhabitats off the talus than their high-elevation counterparts at midday. Finally, pikas living in the atypical habitat had smaller home range sizes compared to those in typical habitat or any previously published home ranges for this species. Our findings indicate that behavioural plasticity likely allows pikas to accommodate atypical conditions in this low-elevation habitat, and that they may rely on critical habitat factors such as suitable microclimate refugia to behaviourally thermoregulate. Together, these results suggest that behavioural adjustments are one important mechanism by which pikas can persist outside of their previously appreciated dietary and thermal niches.

  4. Plastic pikas: Behavioural flexibility in low-elevation pikas (Ochotona princeps).

    PubMed

    Varner, Johanna; Horns, Joshua J; Lambert, Mallory S; Westberg, Elizabeth; Ruff, James S; Wolfenberger, Katelyn; Beever, Erik A; Dearing, M Denise

    2016-04-01

    Behaviour is an important mechanism for accommodating rapid environmental changes. Understanding a species' capacity for behavioural plasticity is therefore a key, but understudied, aspect of developing tractable conservation and management plans under climate-change scenarios. Here, we quantified behavioural differences between American pikas (Ochotona princeps) living in an atypical, low-elevation habitat versus those living in a more-typical, alpine habitat. With respect to foraging strategy, low-elevation pikas spent more time consuming vegetation and less time caching food for winter, compared to high-elevation pikas. Low-elevation pikas were also far more likely to be detected in forested microhabitats off the talus than their high-elevation counterparts at midday. Finally, pikas living in the atypical habitat had smaller home range sizes compared to those in typical habitat or any previously published home ranges for this species. Our findings indicate that behavioural plasticity likely allows pikas to accommodate atypical conditions in this low-elevation habitat, and that they may rely on critical habitat factors such as suitable microclimate refugia to behaviourally thermoregulate. Together, these results suggest that behavioural adjustments are one important mechanism by which pikas can persist outside of their previously appreciated dietary and thermal niches. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Use of non-alpine anthropogenic habitats by American pikas (Ochotona princeps) in western Oregon, USA

    USGS Publications Warehouse

    Manning, Tom; Hagar, Joan C.

    2011-01-01

    The American pika (Ochotona princeps Richardson) has long been characterized in field guides and popular literature as an obligate inhabitant of alpine talus and as having relatively low dispersal capability. However, recent work reveals pikas to have broader habitat associations than previously reported. Over a large portion of the western slope of the Cascade Range in Oregon, pikas inhabit relatively low-elevation sites far from alpine areas and frequently occur in rocky man-made habitats such as roadcuts or rock quarries. We present observations of pikas in these previously overlooked habitats and discuss implications for (1) the proposed listing of the American pika as an endangered or threatened species; (2) furthering our understanding of pika population dynamics, habitat associations, and dispersal capabilites; and (3) management of federal, state, and private forest lands.

  6. Stress hormone concentration in Rocky Mountain populations of the American pika (Ochotona princeps)

    PubMed Central

    Wilkening, Jennifer L.; Ray, Chris; Sweazea, Karen L.

    2013-01-01

    The American pika (Ochotona princeps) is considered a sentinel species for detecting ecological effects of climate change. Pikas are declining within a large portion of their range, but previous studies have focused only on local pika extinction as a metric of change. We designed a procedure which can provide an earlier warning signal, based on non-invasive sampling and analysis of physiological stress in living pikas. Pikas were sampled at several locations in the Rocky Mountains for the measurement of glucocorticoid metabolites (GCMs) in faeces. Using a time series of faecal pellets from 12 individuals, we detected a significant increase in faecal GCM level in response to capture, thus biologically validating the use of a corticosterone enzyme immunoassay. We also established baseline, peak, and post-peak GCM concentrations for pikas in the Rocky Mountains, which varied according to gender and individual. This is the first study to measure stress hormone metabolites in any species of pika. The methods developed and validated in this study can be used to add non-invasive measurements of physiological stress to pika monitoring programmes and other research designed to assess pika vulnerability to predicted changes in climate. Pika monitoring programmes currently in place use a protocol that relates current site use by pikas with data on local habitat characteristics, such as elevation, to infer potential effects of climate change. Data generated by these monitoring studies can be used to identify the trends in site use by pikas in relationship to habitat covariates. However, this approach does not take into account the role of behavioural thermoregulation and the pika's use of microhabitats to ameliorate variations in climate. Incorporating a stress metric, such as GCM concentration, will provide relatively direct evidence for or against the hypothesis that pikas can be stressed by climate regardless of behavioural adaptations. PMID:27293611

  7. Stress hormone concentration in Rocky Mountain populations of the American pika (Ochotona princeps).

    PubMed

    Wilkening, Jennifer L; Ray, Chris; Sweazea, Karen L

    2013-01-01

    The American pika (Ochotona princeps) is considered a sentinel species for detecting ecological effects of climate change. Pikas are declining within a large portion of their range, but previous studies have focused only on local pika extinction as a metric of change. We designed a procedure which can provide an earlier warning signal, based on non-invasive sampling and analysis of physiological stress in living pikas. Pikas were sampled at several locations in the Rocky Mountains for the measurement of glucocorticoid metabolites (GCMs) in faeces. Using a time series of faecal pellets from 12 individuals, we detected a significant increase in faecal GCM level in response to capture, thus biologically validating the use of a corticosterone enzyme immunoassay. We also established baseline, peak, and post-peak GCM concentrations for pikas in the Rocky Mountains, which varied according to gender and individual. This is the first study to measure stress hormone metabolites in any species of pika. The methods developed and validated in this study can be used to add non-invasive measurements of physiological stress to pika monitoring programmes and other research designed to assess pika vulnerability to predicted changes in climate. Pika monitoring programmes currently in place use a protocol that relates current site use by pikas with data on local habitat characteristics, such as elevation, to infer potential effects of climate change. Data generated by these monitoring studies can be used to identify the trends in site use by pikas in relationship to habitat covariates. However, this approach does not take into account the role of behavioural thermoregulation and the pika's use of microhabitats to ameliorate variations in climate. Incorporating a stress metric, such as GCM concentration, will provide relatively direct evidence for or against the hypothesis that pikas can be stressed by climate regardless of behavioural adaptations.

  8. Facing a changing world: Thermal physiology of American pikas (Ochotona princeps)

    USGS Publications Warehouse

    Otto, Hans W; Wilson, James A; Beever, Erik

    2015-01-01

    American pikas (Ochotona princeps) are of concern with respect to warming montane temperatures; however, little information exists regarding their physiological ability to adapt to warming temperatures. Previous studies have shown that pikas have high metabolism and low thermal conductance, which allow survival during cold winters. It has been hypothesized that these characteristics may be detrimental, given the recent warming trends observed in montane ecosystems. We examined resting metabolic rate, surface activity, and den and ambient temperatures (Ta) of pikas in late summer (August 2011 and 2012) at 2 locations in the Rocky Mountains. Resting metabolic rate was calculated to be 2.02 mL O2 · g-1h-1, with a lower critical temperature (LCT) of 28.1 ± 0.2 °C. No upper critical temperature (UCT) could be determined from our data; therefore, the estimated thermoneutral zone (TNZ) was 28.1 °C to at least 35.0 °C (upper experimental temperature). Pikas in this study showed the same bimodal above-talus activity patterns reported in previous studies. Den temperatures in Colorado were correlated with, but consistently lower than, current ambient temperatures. Wyoming den temperatures showed a weak correlation with Ta 20 min prior to the current den temperature. This study is one of few to present data on the physiological response pikas may have to current warming conditions, and the first to perform metabolic measurements in situ. Our data support conclusions of previous studies, specifically MacArthur and Wang (1973, 1974) and Smith (1974), which indicated American pikas may not have the physiological ability to cope with high Ta. Our results also highlight the importance of shaded regions below the talus rocks for behavioral thermoregulation by pikas.

  9. Alpine biodiversity and assisted migration: The case of the American pika (Ochotona princeps)

    USGS Publications Warehouse

    Wilkening, Jennifer L.; Ray, Chris; Ramsay, Nathan G.; Klingler, Kelly

    2015-01-01

    Alpine mammals are predicted to be among the species most threatened by climate change, due to the projected loss and further fragmentation of alpine habitats. As temperature or precipitation regimes change, alpine mammals may also be faced with insurmountable barriers to dispersal. The slow rate or inability to adjust to rapidly shifting environmental conditions may cause isolated alpine species to become locally extirpated, resulting in reduced biodiversity. One proposed method for mitigating the impacts of alpine species loss is assisted migration. This method, which involves translocating a species to an area with more favourable climate and habitat characteristics, has become the subject of debate and controversy in the conservation community. The uncertainty associated with climate change projections, coupled with the thermal sensitivity of many alpine mammals, makes it difficult to a priori assess the efficacy of this technique as a conservation management tool. Here we present the American pika (Ochotona princeps) as a case study. American pikas inhabit rocky areas throughout the western US, and populations in some mountainous areas have become locally extirpated in recent years. We review known climatic and habitat requirements for this species, and also propose protocols designed to reliably identify favourable relocation areas. We present data related to the physiological constraints of this species and outline specific requirements which must be addressed for translocation of viable populations, including wildlife disease and genetic considerations. Finally, we discuss potential impacts on other alpine species and alpine communities, and overall implications for conserving alpine biodiversity in a changing climate.

  10. American pikas (Ochotona princeps) in northwestern Nevada: A newly discovered population at a low-elevation site

    USGS Publications Warehouse

    Beever, E.A.; Wilkening, J.L.; McIvor, D.E.; Weber, S.S.; Brussard, P.F.

    2008-01-01

    The central tenet of island biogeography theory - that species assemblages on islands are functions of island area, isolation from mainlands, and vicariance - has been altered by the demonstrable effects that rapid climate change is imposing on insular faunas, at least in isolated mountaintops. Although populations of American pikas (Ochotona princeps) continue to suffer extirpations, and although the lower bounds of the pika's elevational distribution are shifting upslope across the Great Basin, we report here on the new discovery of a low-elevation population of pikas in a mountain range from which they had not been reported previously. This discovery, particularly in the context of relatively rapid ecological change, highlights the importance of seeking out original sources of information and performing spatially extensive fieldwork. Results presented here further illustrate that although thermal influences appear to be the single strongest determinant of pika distribution currently, such influences interact with a number of other factors to determine persistence.

  11. Patterns of apparent extirpation among isolated populations of pikas (Ochotona princeps) in the Great Basin

    USGS Publications Warehouse

    Beever, Erik A.; Brussard, P.F.; Berger, Joel

    2003-01-01

    We conducted exploratory analyses to examine the relative roles played by natural and anthropogenic influences on persistence of a montane mammal. We revisited historical locations of pikas (Ochotona princeps) within the hydrographic Great Basin during summers of 1994-1999. Seven of 25 populations (28%) reported earlier in the 20th century appeared to have experienced recent extirpations. We assessed causative agents of faunal change using several alternative, but not mutually exclusive, hypotheses. Higher probability of persistence was correlated with greater area of talus habitat at local and mountain-range scales, higher elevation, more easterly longitude, more southern latitude, lack of livestock grazing, greater distance to primary roads, and wilderness management. However, only area of habitat in the mountain range, maximum elevation of talus habitat, and distance to primary roads appeared in the most parsimonious model of persistence when we used Akaike's information criterion model-selection technique. These results suggest that relaxation of montane faunas may occur more rapidly than previously expected; that biogeographic models of species occurrence can be refined by including more proximate factors (e.g., grazing status, proximity to roads); and that habitat-based approaches to modelling vertebrate trends should be accompanied by field data because population loss can occur with no apparent change in habitat.

  12. On the generality of a climate-mediated shift in the distribution of the American pika (Ochotona princeps).

    PubMed

    Erb, Liesl P; Ray, Chris; Guralnick, Robert

    2011-09-01

    Alpine species are among those most threatened by climatic shifts due to their physiological and geographic constraints. The American pika (Ochotona princeps), a small mammal found in mountainous, rocky habitats throughout much of western North America, has experienced recent population extirpations in the Great Basin linked to climatic drivers. It remains unclear whether these patterns of climate-related loss extend to other portions of the species' range. We investigated the distribution of the American pika and the climatic processes shaping this distribution within the Southern Rocky Mountain region. Results from a survey of 69 sites historically occupied by pikas indicate that only four populations have been extirpated within this region over the past few decades. Despite relatively few extirpations, low annual precipitation is implicated as a limiting factor for pika persistence in the Southern Rockies. Extirpations occurred only at sites that were consistently dry over the last century. While there was no climate change signal in our results, these data provide valuable insight into the potential future effects of climate change on O. princeps throughout its range.

  13. Influence of domestic livestock grazing on American Pika (Ochotona princeps) forage and haypiling behavior in the Great Basin. Western North American Naturalist.

    Treesearch

    Constance I. Millar

    2011-01-01

    In a pilot study, I observed a relationship between domestic livestock grazing and location of American pika (Ochotona princeps) haypiles in the eastern Sierra Nevada and several Great Basin mountain ranges. Where vegetation communities adjacent to talus bases (forefields) were grazed, mean distance from the talus borders to the closest fresh...

  14. Relating sub-surface ice features to physiological stress in a climate sensitive mammal, the American pika (Ochotona princeps).

    PubMed

    Wilkening, Jennifer L; Ray, Chris; Varner, Johanna

    2015-01-01

    The American pika (Ochotona princeps) is considered a sentinel species for detecting ecological effects of climate change. Pikas are declining within a large portion of their range, and ongoing research suggests loss of sub-surface ice as a mechanism. However, no studies have demonstrated physiological responses of pikas to sub-surface ice features. Here we present the first analysis of physiological stress in pikas living in and adjacent to habitats underlain by ice. Fresh fecal samples were collected non-invasively from two adjacent sites in the Rocky Mountains (one with sub-surface ice and one without) and analyzed for glucocorticoid metabolites (GCM). We also measured sub-surface microclimates in each habitat. Results indicate lower GCM concentration in sites with sub-surface ice, suggesting that pikas are less stressed in favorable microclimates resulting from sub-surface ice features. GCM response was well predicted by habitat characteristics associated with sub-surface ice features, such as lower mean summer temperatures. These results suggest that pikas inhabiting areas without sub-surface ice features are experiencing higher levels of physiological stress and may be more susceptible to changing climates. Although post-deposition environmental effects can confound analyses based on fecal GCM, we found no evidence for such effects in this study. Sub-surface ice features are key to water cycling and storage and will likely represent an increasingly important component of water resources in a warming climate. Fecal samples collected from additional watersheds as part of current pika monitoring programs could be used to further characterize relationships between pika stress and sub-surface ice features.

  15. Relating Sub-Surface Ice Features to Physiological Stress in a Climate Sensitive Mammal, the American Pika (Ochotona princeps)

    PubMed Central

    Wilkening, Jennifer L.; Ray, Chris; Varner, Johanna

    2015-01-01

    The American pika (Ochotona princeps) is considered a sentinel species for detecting ecological effects of climate change. Pikas are declining within a large portion of their range, and ongoing research suggests loss of sub-surface ice as a mechanism. However, no studies have demonstrated physiological responses of pikas to sub-surface ice features. Here we present the first analysis of physiological stress in pikas living in and adjacent to habitats underlain by ice. Fresh fecal samples were collected non-invasively from two adjacent sites in the Rocky Mountains (one with sub-surface ice and one without) and analyzed for glucocorticoid metabolites (GCM). We also measured sub-surface microclimates in each habitat. Results indicate lower GCM concentration in sites with sub-surface ice, suggesting that pikas are less stressed in favorable microclimates resulting from sub-surface ice features. GCM response was well predicted by habitat characteristics associated with sub-surface ice features, such as lower mean summer temperatures. These results suggest that pikas inhabiting areas without sub-surface ice features are experiencing higher levels of physiological stress and may be more susceptible to changing climates. Although post-deposition environmental effects can confound analyses based on fecal GCM, we found no evidence for such effects in this study. Sub-surface ice features are key to water cycling and storage and will likely represent an increasingly important component of water resources in a warming climate. Fecal samples collected from additional watersheds as part of current pika monitoring programs could be used to further characterize relationships between pika stress and sub-surface ice features. PMID:25803587

  16. Variation in subsurface thermal characteristics of microrefuges used by range core and peripheral populations of the American pika (Ochotona princeps).

    PubMed

    Rodhouse, Thomas J; Hovland, Matthew; Jeffress, Mackenzie R

    2017-03-01

    Microrefuges provide microclimates decoupled from inhospitable regional climate regimes that enable range-peripheral populations to persist and are important to cold-adapted species in an era of accelerated climate change. However, identifying and describing the thermal characteristics of microrefuge habitats is challenging, particularly for mobile organisms in cryptic, patchy habitats. We examined variation in subsurface thermal conditions of microrefuge habitats among different rock substrate types used by the American pika (Ochotona princeps), a climate-sensitive, rock-dwelling Lagomorph. We compared subsurface temperatures in talus and lava substrates in pika survey sites in two US national park units; one park study area on the range periphery and the other in the range core. We deployed paired sensors to examine within-site temperature variation. We hypothesized that subsurface temperatures within occupied sites and structurally complex substrates would be cooler in summer and warmer in winter than unoccupied and less complex sites. Although within-site variability was high, with correlations between paired sensors as low as 47%, we found compelling evidence that pikas occupy microrefuge habitats where subsurface conditions provide more thermal stability than in unoccupied microhabitats. The percentage of days in which microhabitat temperatures were between -2.5 and 25.5°C was significantly higher in occupied sites. Interestingly, thermal conditions were substantially more stable (p < .05) in the lava substrate type identified to be preferentially used by pikas (pahoehoe vs. a'a) in a previous study. Our study and others suggest that thermal stability appears to be the defining characteristic of subsurface microrefuges used by American pikas and is a likely explanation for enigmatic population persistence at the range periphery. Our study exemplifies an integrated approach for studying complex microhabitat conditions, paired with site use surveys and

  17. Distribution and Climatic Relationships of the American Pika (Ochotona princeps) in the Sierra Nevada and Western Great Basin, U.S.A.; Periglacial Landforms as Refugia in Warming Climates

    Treesearch

    Constance I. Millar; Robert D. Westfall

    2010-01-01

    We used a rapid assessment to survey American pika (Ochotona princeps) populations and documented 420 pika site occurrences in southwestern U.S.A. These included 329 sites from the Sierra Nevada (SN), California; 67 from six southwestern Great Basin (swGB) ranges, California and Nevada; 16 from three central Great Basin ranges, Nevada; and 8 from...

  18. Why museums matter: a tale of pinworms (Oxyuroidea: Heteroxynematidae) among pikas (Ochotona princeps and O. collaris) in the American west.

    PubMed

    Hoberg, E P; Pilitt, P A; Galbreath, K E

    2009-04-01

    Permanent and well-supported museum or natural history collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens in the syntype series representing L. (Eugenuris) utahensis, although the published descriptions are in disagreement. Both are identical to L. (Eugenuris) talkeetnaeuris and, as a consequence, are reduced as junior synonyms. Only 2 species of large pinworms, namely L. (Labiostomum) rauschi and L. (Eugenuris) talkeetnaeuris, are widely distributed in Ochotona collaris and O. princeps. Although this serves to clarify the taxonomy for species in these genera, prior records remain confused, as representative voucher specimens from all major surveys in North America were never submitted to museum collections. We strongly suggest that type and voucher series should not be held in private or personal collections, where such are eventually lost, discarded, or destroyed through neglect due to inattention and the absence of curation. The potential to accumulate meaningful baselines for assessment of environmental change is jeopardized if materials from survey and inventory are not routinely submitted to museum collections. The capacity of museum repositories, as a focus for systematics, ecology, and evolutionary studies and for the development of resources for biodiversity informatics, continues to be undervalued and poorly utilized by a cadre of scientists who are dependant on accurate and definitive

  19. Predictors of Current and Longer-Term Patterns of Abundance of American Pikas (Ochotona princeps) across a Leading-Edge Protected Area

    PubMed Central

    Moyer-Horner, Lucas; Beever, Erik A.; Johnson, Douglas H.; Biel, Mark; Belt, Jami

    2016-01-01

    American pikas (Ochotona princeps) have been heralded as indicators of montane-mammal response to contemporary climate change. Pikas no longer occupy the driest and lowest-elevation sites in numerous parts of their geographic range. Conversely, pikas have exhibited higher rates of occupancy and persistence in Rocky Mountain and Sierra Nevada montane ‘mainlands’. Research and monitoring efforts on pikas across the western USA have collectively shown the nuance and complexity with which climate will often act on species in diverse topographic and climatic contexts. However, to date no studies have investigated habitat, distribution, and abundance of pikas across hundreds of sites within a remote wilderness area. Additionally, relatively little is known about whether climate acts most strongly on pikas through direct or indirect (e.g., vegetation-mediated) mechanisms. During 2007–2009, we collectively hiked >16,000 km throughout the 410,077-ha Glacier National Park, Montana, USA, in an effort to identify topographic, microrefugial, and vegetative characteristics predictive of pika abundance. We identified 411 apparently pika-suitable habitat patches with binoculars (in situ), and surveyed 314 of them for pika signs. Ranking of alternative logistic-regression models based on AICc scores revealed that short-term pika abundances were positively associated with intermediate elevations, greater cover of mosses, and taller forbs, and decreased each year, for a total decline of 68% during the three-year study; whereas longer-term abundances were associated only with static variables (longitude, elevation, gradient) and were lower on north-facing slopes. Earlier Julian date and time of day of the survey (i.e., midday vs. not) were associated with lower observed pika abundance. We recommend that wildlife monitoring account for this seasonal and diel variation when surveying pikas. Broad-scale information on status and abundance determinants of montane mammals, especially

  20. Predictors of current and longer-term patterns of abundance of American pikas (Ochotona princeps) across a leading-edge protected area

    USGS Publications Warehouse

    Moyer-Horner, Lucas; Beever, Erik A.; Johnson, Douglas H.; Beil, Mark; Belt, Jami

    2016-01-01

    American pikas (Ochotona princeps) have been heralded as indicators of montane-mammal response to contemporary climate change. Pikas no longer occupy the driest and lowest-elevation sites in numerous parts of their geographic range. Conversely, pikas have exhibited higher rates of occupancy and persistence in Rocky Mountain and Sierra Nevada montane ‘mainlands’. Research and monitoring efforts on pikas across the western USA have collectively shown the nuance and complexity with which climate will often act on species in diverse topographic and climatic contexts. However, to date no studies have investigated habitat, distribution, and abundance of pikas across hundreds of sites within a remote wilderness area. Additionally, relatively little is known about whether climate acts most strongly on pikas through direct or indirect (e.g., vegetation-mediated) mechanisms. During 2007–2009, we collectively hiked >16,000 km throughout the 410,077-ha Glacier National Park, Montana, USA, in an effort to identify topographic, microrefugial, and vegetative characteristics predictive of pika abundance. We identified 411 apparently pika-suitable habitat patches with binoculars (in situ), and surveyed 314 of them for pika signs. Ranking of alternative logistic-regression models based on AICc scores revealed that short-term pika abundances were positively associated with intermediate elevations, greater cover of mosses, and taller forbs, and decreased each year, for a total decline of 68% during the three-year study; whereas longer-term abundances were associated only with static variables (longitude, elevation, gradient) and were lower on north-facing slopes. Earlier Julian date and time of day of the survey (i.e., midday vs. not) were associated with lower observed pika abundance. We recommend that wildlife monitoring account for this seasonal and diel variation when surveying pikas. Broad-scale information on status and abundance determinants of montane mammals, especially

  1. Predictors of Current and Longer-Term Patterns of Abundance of American Pikas (Ochotona princeps) across a Leading-Edge Protected Area.

    PubMed

    Moyer-Horner, Lucas; Beever, Erik A; Johnson, Douglas H; Biel, Mark; Belt, Jami

    2016-01-01

    American pikas (Ochotona princeps) have been heralded as indicators of montane-mammal response to contemporary climate change. Pikas no longer occupy the driest and lowest-elevation sites in numerous parts of their geographic range. Conversely, pikas have exhibited higher rates of occupancy and persistence in Rocky Mountain and Sierra Nevada montane 'mainlands'. Research and monitoring efforts on pikas across the western USA have collectively shown the nuance and complexity with which climate will often act on species in diverse topographic and climatic contexts. However, to date no studies have investigated habitat, distribution, and abundance of pikas across hundreds of sites within a remote wilderness area. Additionally, relatively little is known about whether climate acts most strongly on pikas through direct or indirect (e.g., vegetation-mediated) mechanisms. During 2007-2009, we collectively hiked >16,000 km throughout the 410,077-ha Glacier National Park, Montana, USA, in an effort to identify topographic, microrefugial, and vegetative characteristics predictive of pika abundance. We identified 411 apparently pika-suitable habitat patches with binoculars (in situ), and surveyed 314 of them for pika signs. Ranking of alternative logistic-regression models based on AICc scores revealed that short-term pika abundances were positively associated with intermediate elevations, greater cover of mosses, and taller forbs, and decreased each year, for a total decline of 68% during the three-year study; whereas longer-term abundances were associated only with static variables (longitude, elevation, gradient) and were lower on north-facing slopes. Earlier Julian date and time of day of the survey (i.e., midday vs. not) were associated with lower observed pika abundance. We recommend that wildlife monitoring account for this seasonal and diel variation when surveying pikas. Broad-scale information on status and abundance determinants of montane mammals, especially for

  2. Pika (Ochotona princeps) losses from two isolated regions reflect temperature and water balance, but reflect habitat area in a mainland region

    USGS Publications Warehouse

    Beever, Erik A.; Perrine, John D.; Rickman, Tom; Flores, Mary; Clark, John P.; Waters, Cassie; Weber, Shana S.; Yardley, Braden; Thoma, David P.; Chesley-Preston, Tara; Goehring, Kenneth E.; Magnuson, Michael; Nordensten, Nancy; Nelson, Melissa; Collins, Gail H.

    2016-01-01

    Although biotic responses to contemporary climate change are spatially pervasive and often reflect synergies between climate and other ecological disturbances, the relative importance of climatic factors versus habitat extent for species persistence remains poorly understood. To address this shortcoming, we performed surveys for American pikas (Ochotona princeps) at > 910 locations in 3 geographic regions of western North America during 2014 and 2015, complementing earlier modern (1994–2013) and historical (1898–1990) surveys. We sought to compare extirpation rates and the relative importance of climatic factors versus habitat area for pikas in a mainland-versus-islands framework. In each region, we found widespread evidence of distributional loss—local extirpations, upslope retractions, and encounter of only old sign. Locally comprehensive surveys suggest extirpation of O. princeps from 5 of 9 new sites from the hydrographic Great Basin and from 11 of 29 sites in northeastern California. Although American pikas were recorded as recently as 2011 in Zion National Park and in 2012 from Cedar Breaks National Monument in Utah, O. princeps now appears extirpated from all reported localities in both park units. Multiple logistic regressions for each region suggested that both temperature-related and water-balance-related variables estimated from DAYMET strongly explained pika persistence at sites in the Great Basin and in Utah but not in the Sierra-Cascade “mainland” portion of northeastern California. Conversely, talus-habitat area did not predict American pika persistence in the Great Basin or Utah but strongly predicted persistence in the Sierra-Cascade mainland. These results not only add new areas to our understanding of long-term trend of the American pika’s distribution, but also can inform decisions regarding allocation of conservation effort and management actions. Burgeoning research on species such as O. princeps has collectively demonstrated the

  3. Climate Tolerances and Habitat Requirements Jointly Shape the Elevational Distribution of the American Pika (Ochotona princeps), with Implications for Climate Change Effects.

    PubMed

    Yandow, Leah H; Chalfoun, Anna D; Doak, Daniel F

    2015-01-01

    Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps) is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions.

  4. Using High Resolution Remotely Sensed Data to Predict Territory Occupancy and Mircrorefugia for a Habitat Specialist, the American Pika (Ochotona princeps)

    NASA Astrophysics Data System (ADS)

    Beers, A.; Ray, C.

    2015-12-01

    Climate change is likely to affect mountainous areas unevenly due to the complex interactions between topography, vegetation, and the accumulation of snow and ice. This heterogeneity will complicate relationships between species presence and large-scale drivers such as precipitation and make predicting habitat extent and connectivity much more difficult. We studied the potential for fine-scale variation in climate and habitat use throughout the year in the American pika (Ochotona princeps), a talus specialist of mountainous western North America known for strong microhabitat affiliation. Not all areas of talus are likely to be equally hospitable, which may reduce connectivity more than predicted by large-scale occupancy drivers. We used high resolution remotely sensed data to create metrics of the terrain and land cover in the Niwot Ridge (NWT) LTER site in Colorado. We hypothesized that pikas preferentially use heterogeneous terrain, as it might foster greater snow accumulation, and used radio telemetry to test this with radio-collared pikas. Pikas use heterogeneous terrain during snow covered periods and less heterogeneous area during the summer. This suggests that not all areas of talus habitat are equally suitable as shelter from extreme conditions but that pikas need more than just shelter from winter cold. With those results we created a predictive map using the same habitat metrics to model the extent of suitable habitat across the NWT area. These strong effects of terrain on pika habitat use and territory occupancy show the great utility that high resolution remotely sensed data can have in ecological applications. With increasing effects of climate change in mountainous regions, this modeling approach is crucial for quantifying habitat connectivity at both small and large scales and to identify potential refugia for threatened or isolated species.

  5. Climate Tolerances and Habitat Requirements Jointly Shape the Elevational Distribution of the American Pika (Ochotona princeps), with Implications for Climate Change Effects

    PubMed Central

    Yandow, Leah H.; Chalfoun, Anna D.; Doak, Daniel F.

    2015-01-01

    Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps) is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions. PMID:26244851

  6. When cold is better: climate-driven elevation shifts yield complex patterns of diversification and demography in an alpine specialist (American pika, Ochotona princeps).

    PubMed

    Galbreath, Kurt E; Hafner, David J; Zamudio, Kelly R

    2009-11-01

    The genetic consequences of climate-driven range fluctuation during the Pleistocene have been well studied for temperate species, but cold-adapted (e.g., alpine, arctic) species that may have responded uniquely to past climatic events have received less attention. In particular, we have no a priori expectation for long-term evolutionary consequences of elevation shifts into and out of sky islands by species adapted to alpine habitats. Here, we examined the influence of elevation shifts on genetic differentiation and historical demography in an alpine specialist, the American pika (Ochotona princeps). Pika populations are divided into five genetic lineages that evolved in association with separate mountain systems, rather than lineages that reflect individual sky islands. This suggests a role for glacial-period elevation shifts in promoting gene flow among high-elevation populations and maintaining regional cohesion of genetic lineages. We detected a signature of recent demographic decline in all lineages, consistent with the expectation that Holocene climate warming has driven range retraction in southern lineages, but unexpected for northern populations that presumably represent postglacial expansion. An ecological niche model of past and future pika distributions highlights the influence of climate on species range and indicates that the distribution of genetic diversity may change dramatically with continued climate warming.

  7. Discovery of new Ohbayashinema spp. (nematoda: heligomosomoidea) in Ochotona princeps and O. cansus (lagomorpha: ochotonidae) from western North America and central Asia, with considerations of historical biogeography

    USDA-ARS?s Scientific Manuscript database

    Three new species of Ohbayashinema (Nematoda, Heligmosomoidea) are described from localities in western North America and central Asia. Two of these species, Ohbayashinema nearctica n. sp and O. aspeira n. sp. are parasitic in American pika, Ochotona princeps. Ohbayashinema nearctica is differentiat...

  8. Pulmonary alveolar microlithiasis in Afghan pika (Ochotona rufescens rufescens).

    PubMed

    Madarame, H; Kumagai, M; Suzuki, J; Watanabe, A; Konno, S

    1989-07-01

    Lung lesions of 60 Afghan pikas (Ochotona rufescens rufescens) were examined histologically; 38 cases of pulmonary alveolar microlithiasis were found. Neither sex was predominantly affected, and there was no predilection for age.

  9. An automatic watering device for the pika (Ochotona rufescens rufescens).

    PubMed

    Matsuzawa, T; Sagawa, S; Kuwabara, K

    1980-10-01

    An automatic watering device was developed for the pika (Ochotona rufuescens rufescens), using drinking nozzles for rat and plastic pipes. This device was used for at least one year without any mechanical troubles, resulting in labor saving of animal caretakers. No difference in growth was observed between pikas reared with the automatic watering device and those maintained with conventional watering bottles.

  10. Pyrogenic responses of the pika, Ochotona rufescens rufescens.

    PubMed

    Sakai, T; Kodama, Y; Horiuchi, S

    1991-07-01

    In 3-month-old male and female pikas, Ochotona rufescens rufescens, reared at an ambient temperature of 25 degrees C, the mean within-day body temperature was 39.2 degrees C without significant variance. At an ambient temperature of 35 degrees C it increased markedly in males while decreased slightly at 5 degrees C. The pikas showed lower sensitivity than Japanese white rabbits to a pyrogenic E. coli endotoxin.

  11. Characterization of mitochondrial DNA from the pika (Ochotona rufescens rufescens).

    PubMed

    Lesca, C; Moisand, A; Puget, A

    1976-01-01

    Further to anatomical and physiological studies performed on the pika (Ochotona rufescens rufescens), a new laboratory animal, the main characteristics of the mitochondrial DNA from its liver are defined. The buoyant density of this DNA is 1.695 g/cm3, its length 5.30 mum,, i.e., 3.17 times that of the replicative form of phiX 174. It could have approximately 16 500 base pairs. The DNA from the pika is very similar to that of the rat or the rabbit, although these animals show great physiological differences.

  12. Actinomyces gaoshouyii sp. nov., isolated from plateau pika (Ochotona curzoniae).

    PubMed

    Meng, Xiangli; Wang, Yiting; Lu, Shan; Lai, Xin-He; Jin, Dong; Yang, Jing; Xu, Jianguo

    2017-09-01

    Two strains (pika_113T and pika_114) of a previously undescribed Actinomyces-like bacterium were recovered from the intestinal contents of plateau pika (Ochotona curzoniae) on the Tibet-Qinghai Plateau, China. Results from biochemical characterization indicated that the two strains were phenotypically homogeneous and distinct from other previously described species of the genus Actinomyces. Based on the comparison of 16S rRNA gene sequences and genome analysis, the bacteria were determined to be a hitherto unknown subline within the genus Actinomyces, being most closely related to type strains of Actinomyces denticolens and Actinomyces timonensis with a respective 97.2 and 97.1 % similarity in their 16S rRNA gene sequences. Phylogenetic analyses confirmed that pika_113T was well separated from any other recognized species of the genus Actinomyces and within the cluster with A. denticolens and A. timonensis. The genome of strain pika_113T displayed less than 42 % relatedness in DNA-DNA hybridization with all the available genomes of existing species of the genus Actinomyces in the NCBI database. Collectively, based on the phenotypic characteristics and phylogenetic analyses results, we propose the novel isolates as representatives of Actinomyces gaoshouyii sp. nov. The type strain of Actinomyces gaoshouyii is pika_113T (=CGMCC 4.7372T=DSM 104049T), with a genomic DNA G+C content of 71 mol%.

  13. Cuboidal epithelium lining of the parietal layer of Bowman's capsule in Afghan pikas (Ochotona rufescens rufescens).

    PubMed

    Madarame, H; Kumagai, M; Motooka, N; Konno, S

    1991-01-01

    Kidneys of 64 Afghan pikas (Ochotona rufescens rufescens) were examined histologically. Seven of 21 males and two of 21 females over 6 months of age had a cuboidal epithelium lining of the parietal layer of Bowman's capsule.

  14. Biogeographical study of plateau pikas Ochotona curzoniae (Lagomorpha, Ochotonidae).

    PubMed

    Yu, Fahong; Li, Shiping; Kilpatrick, William C; McGuire, Peter M; He, Kai; Wei, Wanhong

    2012-08-01

    We reconstructed the demographic history of the plateau pika (Ochotona curzoniae) on the Qinghai-Tibetan plateau by using genetic variation data obtained from spatially distributed populations across much of the plateau. We obtained sequence data, including cob (1,140 bp) and D-loop sequences (732 bp), from 144 individuals at sites ranging from the high-altitude interior to the relatively low-altitude northeastern plateau, and identified 37 and 42 unique haplotypes, respectively. Phylogenetic analysis and haplotype networks based on the individual and the combined datasets of cob and D-loop sequences clustered all populations into four well-supported major groups, and the interaction between vicariance, dispersal, and habitat fragmentation resulted in the current geographical distribution and genetic diversity of O. curzoniae on the plateau. Analysis of molecular variance (AMOVA) and mismatch distribution suggested that the recent continuous uplifts of the plateau contributed to the radiation and diversification of the O. curzoniae populations occurring there.

  15. Interannual Variation in Timing of Parturition and Growth of Collared Pikas (Ochotona collaris) in the Southwest Yukon.

    PubMed

    Franken, Renee J; Hik, David S

    2004-04-01

    The length of the snow-free season has a significant influence on reproduction and growth in northern alpine environments, and these life history traits may provide sensitive indicators of the responses of organisms to climate change. We examined growth rates and timing of parturition of collared pikas (Ochotona collaris) from 1995-2002 in the Ruby Range, Yukon Territory, Canada. Growth rates were best described using a Gompertz model, in which the asymptotic mass, determined from the average male and female weights, was 157 g, the growth rate constant (K) was 0.0557, and the age at inflection (I) was 18.12 days, for a birth weight of 10 g. The maximum growth rate for North American pikas (O. collaris and O. princeps) increased with latitude, with maximum growth rates being approximately one-third greater in northern populations where the snow-free season is less than three months long. The mean parturition date varied significantly among years from 3 June to 3 July, and delayed parturition was correlated with indices of high snow accumulation and, to a lesser extent, late spring snowmelt. However, parturition date did not significantly affect the subsequent over-winter survival of juveniles in this population, suggesting that pikas are able to adjust to seasonal uncertainty associated with highly variable spring conditions.

  16. Pathology of excessive iron storage in the Afghan pika (Ochotona rufescens rufescens).

    PubMed

    Madarame, H; Kumagai, M; Suzuki, J; Watanabe, A; Konno, S

    1990-10-01

    Iron deposition in the tissues of 30 Afghan pikas (Ochotona rufescens rufescens) was examined histopathologically. In all cases, iron deposits were present in the liver and in two-thirds of cases, there was portal fibrosis with tissue injury. In animals, in general, tissue injury induced by iron overload is usually mild and only in a few exceptional species does hepatic haemochromatosis occur. Thus, Afghan pikas are a rare example of reaction to iron overloading.

  17. Joint study on the teratogenic sensitivity of the Pika (Ochotona rufescens rufescens) to selected drugs.

    PubMed

    Nishimura, H; Shiota, K; Uwabe, C; Nomura, T

    1986-10-01

    A collaborative study was conducted to investigate the teratological susceptibility of the Pika (Ochotona rufescens rufescens) to selected teratogenic chemicals: cyclophosphamide, 6-mercaptopurine, 5-fluorouracil, 6-aminonicotinamide, actinomycin D, ethylurethan, ampicillin, tetracycline, thalidomide, diphenylhydantoin, hypervitaminosis A, aspirin, dexamethasone, betamethasone and bredinin. Some of the chemicals were shown to be teratogenic in the Pika, but this animal was generally more resistant to their teratogenicity than the rabbit and rodents. In the Pika, thalidomide did not induce any typical limb defects, which have been produced in the rabbit. Pikas reproduce well and appear to have no substantial disadvantages as an animal species for teratological studies. Thus, the Pika may be useful as a new non-rodent species for teratological testings.

  18. Primary irritant reactions in the skin of the pika, Ochotona rufescens rufescens.

    PubMed

    Sakai, T; Kodama, Y; Yamamoto, H; Horiuchi, S; Nomura, T

    1989-10-01

    The skin of the pika (Ochotona rufescens rufescens) was found to be remarkably sensitive to the primary irritation of sodium hydroxide, as compared with the skin of the rabbit. After exposure to 0.1 N sodium hydroxide for 24 hr, the pika skin showed severe erosion, ulceration and necrosis as well as crust formation and hyperkeratosis with vascular dilation, and cell infiltration. The changes appeared already within 1 hr after 1 N or 3 hr after 0.1 N sodium hydroxide application. After application of acetic acid, changes were apparent while less remarkable.

  19. Parasite species associated with wild plateau pika (Ochotona curzoniae) in southeastern Qinghai Province, China.

    PubMed

    Wang, Chengmin; He, Hongxuan; Li, Ming; Lei, Fumin; Root, J Jeffrey; Wu, Yanyun; Qin, Jianhua

    2009-04-01

    A survey was conducted to determine the prevalence and seasonal abundance of egg, larval, and adult stages of helminths; oocyts of protozoans; and ectoparasites of plateau pikas (Ochotona curzoniae) in seven areas of southeastern Qinghai Province, China, during August 2006 and May 2007. Fecal samples collected from 430 plateau pikas were examined by the modified McMaster technique, which revealed that 83% of the samples contained eggs from two or more helminth species. Mean fecal egg counts were generally moderate and showed the same trend irrespective of the age or sex of the pikas. The prevalence and counts of cestode eggs showed strong seasonal relationships that corresponded with the rainfall pattern in the study area during the study period. Of the 430 plateau pika examined at necropsy, 89% contained adult nematode or cestode species, but none of these contained adult trematode species or protozoans. Overall, six genera of adult nematodes including Oesophagostomum sp., Cephaluris coloradensis, Eugenuris schumakowiescsi, Haemonchus sp., Trichuris sp., and Chbertiinae sp.; three genera of adult cestodes including Schizorchis sp., Ochotonae sp., and Hymenolepis nana; three ectoparasite species including Hypoderma curzonial, Pulex sp., and Ixodes ovatus; and one proscolex stage of a cestode, Echinococcus multilocularis or Echinococcus shiquicus, were encountered during the study. Other genera examined occurred in low numbers, which did not allow any meaningful comparisons. Overall, results suggest that four parasite species, Hypoderma curzonial, Pulex sp., Ixodes ovatus Neumann, and Cephaluris coloradensis, may be regulating factors in controlling future numbers of plateau pika in this study area. These data provide evidence of a natural biologic control mechanism of plateau pika on grassland habitats, and may be of use for identifying the mechanism of transmission of parasites between plateau pika, livestock, and humans.

  20. [Cloning and characterization of lactate dehydrogenase C4 from pika ochotona curzoniae].

    PubMed

    Zhang, Q -L; Yang, M; Zhao, Y -Y; Zhang, S -Z; He, Q -H; Meng, X -Y; Tan, W -R

    2014-01-01

    Lactate dehydrogenase C4 (LDH-C4) is considered to be a good target protein for the development of contraceptive drugs. To develop contraceptive rodenticide against pika (Ochotona curzoniae) LDH-C4, the pika LDH-C gene was cloned and expressed in Escherichia coli. The recombinant protein was purified and characterized. The cDNA of pika LDH-C gene was cloned by RACE method. The cDNA was 1498 bp in length containing an ORF of 996 bp which encoded a polypeptide of 332 amino acids. The ORF of pika LDH-C was introduced in E. coli and expressed with no fusion tags added. The recombinant LDH-C4 protein was purified by heating, affinity chromatography and ion-exchange chromatography. The recombinant pika LDH-C4 was a tetramer with a molecular weight of approximately 140 kDa, and it had temperature-dependent catalytic activity, as it was thermally stable up to 60 degrees C. The optimal pH values in the forward and backward reactions were around 7.48 and 10.28, respectively. The apparent Michaelis constants for pyruvate and lactate were 51.2 +/- 3.8 and 8568.8 +/- 409 microM respectively. The inhibition constant for oxalic acid was 11.8 +/- 3.5 mM. This study laid a solid foundation for contraceptive rodenticide development against pika LDH-C4.

  1. The natural tolerance of the afghan pika (Ochotona rufescens) to morphine.

    PubMed

    Puget, A; Cros, J; Meunier, J C

    1979-02-01

    A lagomorph, the afghan pika, Ochotona rufescens showed no effect whatever following the subcutaneous injection of morphine in doses up to 50 mg per 100 g of body weight, i.e. 250 times the ED50 for the rat. Higher doses were toxic and induced convulsions. However, the pika is responsive to synthetic opiates such as etorphine, pentazocine and phenoperidine. Interestingly enough, morphine antagonized the opiate response elicited by those narcotics to which the animal is sensitive. Pharmacokinetic analysis demonstrated that morphine enters the pika's brain as readily as it does the rat's. In addition, opiate receptor sites, which are present in normal amounts in pika brain retained their high affinity for 3H-etorphine (KD = 0.3 nM), 3H-naloxone (KD = 1.2 nM) and morphine. Moreover, binding of morphine to pika brain homogenates was inhibited in the presence of sodium ions (agonist response). Therefore, the antagonism of phenoperidine action by morphine appeared not to occur at the opiate receptor site; the mechanism of the pika's natural tolerance to morphine may reside in molecular events that normally preceed (metabolism?) or follow (enzyme activation?) the interaction between the drug and its specific recognition sites.

  2. Effectiveness of 10 polymorphic microsatellite markers for parentage and pedigree analysis in plateau pika (Ochotona curzoniae).

    PubMed

    Li, Kexin; Geng, Jianing; Qu, Jiapeng; Zhang, Yanming; Hu, Songnian

    2010-11-10

    The plateau pika (Ochotona curzoniae) is an underground-dwelling mammal, native to the Tibetan plateau of China. A set of 10 polymorphic microsatellite loci has been developed earlier. Its reliability for parentage assignment has been tested in a plateau pika population. Two family groups with a known pedigree were used to validate the power of this set of markers. The error in parentage assignment using a combination of these 10 loci was very low as indicated by their power of discrimination (0.803 - 0.932), power of exclusion (0.351 - 0.887), and an effectiveness of the combined probability of exclusion in parentage assignment of 99.999%. All the offspring of a family could be assigned to their biological mother; and their father or relatives could also be identified. This set of markers therefore provides a powerful and efficient tool for parentage assignment and other population analyses in the plateau pika.

  3. Effectiveness of 10 polymorphic microsatellite markers for parentage and pedigree analysis in plateau pika (Ochotona curzoniae)

    PubMed Central

    2010-01-01

    Background The plateau pika (Ochotona curzoniae) is an underground-dwelling mammal, native to the Tibetan plateau of China. A set of 10 polymorphic microsatellite loci has been developed earlier. Its reliability for parentage assignment has been tested in a plateau pika population. Two family groups with a known pedigree were used to validate the power of this set of markers. Results The error in parentage assignment using a combination of these 10 loci was very low as indicated by their power of discrimination (0.803 - 0.932), power of exclusion (0.351 - 0.887), and an effectiveness of the combined probability of exclusion in parentage assignment of 99.999%. Conclusion All the offspring of a family could be assigned to their biological mother; and their father or relatives could also be identified. This set of markers therefore provides a powerful and efficient tool for parentage assignment and other population analyses in the plateau pika. PMID:21062500

  4. Seasonal thermogenesis and body mass regulation in plateau pikas (Ochotona curzoniae).

    PubMed

    Wang, Jian-Mei; Zhang, Yan-Ming; Wang, De-Hua

    2006-09-01

    Changes in photoperiod, ambient temperature and food availability trigger seasonal acclimatization in physiology and behavior of many animals. In the present study, seasonal adjustments in body mass and in several physiological, hormonal, and biochemical markers were examined in wild-captured plateau pikas (Ochotona curzoniae) from the Qinghai-Tibetan plateau. Our results showed that plateau pikas maintained a relatively constant body mass throughout the year and showed no seasonal changes in body fat mass and circulating levels of serum leptin. However, nonshivering thermogenesis, cytochrome c oxidase activity, and mitochondrial uncoupling protein 1 (UCP1) contents in brown adipose tissues were significantly enhanced in winter. Further, serum leptin levels were positively correlated with body mass and body fat mass while negatively correlated with UCP1 contents. Together, these data suggest that plateau pikas mainly depend on increasing thermogenic capacities, rather than decreasing body mass, to cope with cold, and leptin may play a potential role in their thermogenesis and body mass regulation.

  5. Distance and temperature effects on pika forage

    Treesearch

    Jim F. Fowler; Barbara Smith; Steve Overby

    2014-01-01

    The American pika, Ochotona princeps, has been referred to as a 'canary in the coal mine' when it comes to climate change. This small rabbit relative inhabits cool alpine and subalpine mountain areas and has been shown to be sensitive to higher temperatures from both physiological experiments (Smith 1974) and from past climate transitions in the late...

  6. Relationships of Periglacial Processes to Habitat Quality and Thermal Environment of Pikas (Lagomorpha, Ochotona) in Alpine and High-Latitude Environments (Invited)

    NASA Astrophysics Data System (ADS)

    Millar, C. I.; Smith, A. T.; Hik, D. S.

    2009-12-01

    Patterned-ground and related periglacial features such as rock-glaciers and fractured-rock talus are emblematic of cold and dry arctic environments. The freeze-thaw processes that cause these features were first systematically investigated in the pioneering work of Linc Washburn. Unusual internal and autonomous micro-climatic and hydrologic processes of these features, however, are only beginning to be understood. Such features occur also in temperate latitude mountains, often in surprising abundance in regions such as the Great Basin (NV, USA) and San Juan Mtns (CO, USA), where they occur as active as well as relict (neoglacial or Pleistocene) features. Rock-dwelling species of pikas (Ochotona) in temperate North American and Asian mountains and in North American high-latitudes have long been known for their preference for talus habitats. We are investigating geomorphic, climatic, and hydrologic attributes of these periglacial features for their role in habitat quality and thermal environment of pikas. PRISM-modeled and observed climatic conditions from a range of talus types for Ochotona princeps in California and the western Great Basin (USA) indicate that, 1) thermal conditions of intra-talus-matrix in summer are significantly colder than talus-surface temperatures and colder than adjacent slopes and forefield wetlands where pika forage; 2) near-talus-surface locations (where haypiles are situated) are warmer in winter than intra-talus-matrix temperatures; 3) high-quality wetland vegetation in talus forefields is promoted by year-round persistence of outlet springs, seeps, and streams characteristic of active taluses. The importance of snowpack to winter thermal conditions is highlighted from these observations, suggesting a greater sensitivity of habitat in dry temperate regions such as eastern California and Nevada USA to warming winter minimum temperatures than in regions or elevations where snowpacks are more persistent. In regions where warming air

  7. Revisiting the past to foretell the future: summer temperature and habitat area predict pika extirpations in California

    Treesearch

    Joseph A. E. Stewart; John D. Perrine; Lyle B. Nichols; James H. Thorne; Constance I. Millar; Kenneth E. Goehring; Cody P. Massing; David H. Wright; Brett Riddle

    2015-01-01

    Aim The American pika (Ochotona princeps) appears to have experienced climate mediated upslope range contraction in the Great Basin of North America, but this result has not yet been extended to other portions of the pika’s range. Our goals were: first, to determine the environmental parameters that most influence...

  8. The chromosomes of Tsing-Ling pika, Ochotona huangensis Matschie, 1908 (Lagomorpha, Ochotonidae)

    PubMed Central

    Vakurin, Alexey A.; Korablev, Vladimir P.; Xue-Long, Jiang; Grigor'eva, Tat'iana V.

    2012-01-01

    Abstract The karyotype of the Tsing-Ling (Huanghe) pika, Ochotona huangensis Matschie, 1908 from the forest habitats of the Qinling Mountains (Shaanxi Province, China) was described for the first time. The chromosome set contains 42 chromosomes (NFa=80). The autosomes are 15 meta-submetacentric pairs and 5 subtelocentric pairs. The X chromosome is a medium sized submetacentric; the Y chromosome is a small sized acrocentric. C-banding revealed a localization of heterochromatin in the pericentromeric regions of all autosomes. PMID:24260675

  9. Opioid receptor types in the brain of the Afghan pika (Ochotona rufescens), a species which is naturally tolerant to morphine.

    PubMed

    Farges, R C; Puget, A; Moisand, C; Meunier, J C

    1988-01-01

    The rabbit is normally sensitive to morphine while another lagomorph, the Afghan pika Ochotona rufescens is naturally tolerant to the analgesic effects elicited by the opium alkaloid. In spite of the different responsiveness of the two species to morphine we find that the pika brain and the rabbit brain both contain a mixture of mu-, delta- and kappa-opioid sites in nearly the same proportions: 46-47% mu, 23% delta and 28-30% kappa. Moreover, apparent binding of morphine in pika and rabbit brain membranes is inhibited in the presence of Na+ ions and/or of 5-guanylylimidodiphosphate indicating that morphine should behave as an opiate agonist (analgesic) not only in rabbits, which it does but also in pikas, which it does not. Taken together these results suggest that the natural tolerance of the Afghan pika to morphine may not reside in modified opioid receptor types and that its origin should be sought elsewhere.

  10. Comparative ventilatory strategies of acclimated rats and burrowing plateau pika (Ochotona curzoniae) in response to hypoxic-hypercapnia.

    PubMed

    Pichon, Aurélien; Voituron, Nicolas; Bai, Zhenzhong; Jeton, Florine; Tana, Wuren; Marchant, Dominique; Jin, Guoen; Richalet, Jean-Paul; Ge, Ri-Li

    2015-09-01

    The objective of this study was to compare the different ventilatory strategies that help in coping with hypoxic-hypercapnia environment among two species: use acclimated rats and plateau pikas (Ochotona curzoniae) that live in Tibetan plateaus, and have been well adjusted to high altitude. Arterial blood samples taken at 4100 m of elevation in acclimatized rats and adapted pikas revealed inter-species differences with lower hemoglobin and hematocrit and higher blood pH in pikas. A linear and significant increase in minute ventilation was observed in pikas, which help them to cope with hypoxic-hypercapnia. Pikas also displayed a high inspiratory drive and an invariant respiratory timing regardless of the conditions. Biochemical analysis revealed that N-methyl-D-aspartate receptor (NMDA) receptor gene and nNOS gene are highly conserved between rats and pikas, however pikas have higher expression of NMDA receptors and nNOS compared to rats at the brainstem level. Taken together, these results suggest that pikas have developed a specific ventilatory pattern supported by a modification of the NMDA/NO ventilatory central pathways to survive in extreme conditions imposed on the Tibetan plateaus. These physiological adaptive strategies help in maintaining a better blood oxygenation despite high CO2 concentration in burrows at high altitude. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. [Hypoxic adaptation of the hearts of plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae)].

    PubMed

    Qi, Xin-Zhang; Wang, Xiao-Jun; Zhu, Shi-Hai; Rao, Xin-Feng; Wei, Lian; Wei, Deng-Bang

    2008-06-25

    Plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzniae) are native to the Qinghai-Tibet plateau. To study their adaptive mechanisms, the ratios of heart weight to body weight (HW/BW) and right to left ventricular plus septum weights [RV/(LV+S)] were determined; the microvessel density (MVD) of cardiac muscle were measured by immunohistochemical staining; the numerical density on area (N(A)), volume density (V(V)), specific surface (δ), and surface density (S(V)) of mitochondria were obtained by microscopy and stereology; the contents of myoglobin (Mb) and lactic acid (LD), and the activity of lactate dehydrogenase (LDH) in cardiac muscle were analyzed by spectrophotometer. The results showed that the HW/BW of plateau zokor [(4.55±0.26)%] and plateau pika [(4.41±0.38)%] was significantly greater than that of Sprague-Dawley (SD) rat [(3.44±0.41)%] (P<0.05), but the RV/(LV+S) [(22.04±1.98)%, (25.53±3.41)%] was smaller than that of SD rats [(44.23±3.87)%] (P<0.05). The MVD and N(A) of cardiac muscle were 1688.631±250.253 and 0.768±0.123 in SD rat, 2002.888±367.466 and 0.868±0.159 in plateau pika and 2 990.643±389.888 and 1.012±0.133 in plateau zokor. The V(V) of mitochondria in plateau zokor (0.272±0.045) was significantly lower than that in plateau pika (0.343±0.039) and SD rat (0.321±0.048) (P<0.05), while the δ of mitochondria in plateau zokor (9.409±1.238) was higher than that in plateau pika (6.772±0.892) and SD rat (7.287±1.373) (P<0.05). The S(V) of mitochondria in plateau pika (2.322±0.347) was not obviously different from that in plateau zokor (2.468±0.380) and SD rat (2.227±0.377), but that in plateau zokor was significantly higher than that in SD rat (P<0.05). The contents of Mb in cardiac muscle of plateau zokor [(763.33±88.73) nmol/g] and plateau pika [(765.96±28.47) nmol/g] were significantly higher than that of SD rat [(492.38±72.14) nmol/g] (P<0.05), the content of LD in plateau zokor [(0.57±0.06) mmol/L] was

  12. Forage selection by Royle's pika (Ochotona roylei) in the western Himalaya, India.

    PubMed

    Bhattacharyya, Sabuj; Adhikari, Bhupendra S; Rawat, Gopal S

    2013-10-01

    Forage selection decisions of herbivores are often complex and dynamic; they are modulated by multiple cues, such as quality, accessibility and abundance of forage plants. To advance the understanding of plant-herbivore interactions, we explored foraging behavior of the alpine lagomorph Royle's pika (Ochotona roylei) in Kedarnath Wildlife Sanctuary, India. Pika bite counts on food plants were recorded through focal sampling in three permanently marked plots. Food plant abundance was recorded by traditional quadrat procedures; forage selection was estimated with Jacob's selection index. Multiple food-choice experiments were conducted to determine whether forage selection criteria would change with variation in food plant composition. We also analyzed leaf morphology and nutrient content in both major food plants and abundantly available non-food plants. Linear regression models were used to test competing hypotheses in order to identify factors governing forage selection. Royle's pika fed primarily on 17 plant species and each forage selection decision was positively modulated by leaf area and negatively modulated by contents of avoided substances (neutral detergent fiber, acid detergent fiber, acid detergent lignin and tannin) in food plants. Furthermore, significance of the interaction term "leaf size × avoided substance" indicates that plants with large leaves were selected only when they had low avoided substance content. The forage selection criteria did not differ between field and laboratory experiments. The parameter estimates of best fit models indicate that the influence of leaf size or amount of avoided substance on pika forage selection was modulated by the magnitude of predation risk. Copyright © 2013 Elsevier GmbH. All rights reserved.

  13. VEGF189 Expression Is Highly Related to Adaptation of the Plateau Pika (Ochotona curzoniae) Inhabiting High Altitudes

    PubMed Central

    Li, Hongge; Guo, Songchang; Ren, Yongming; Wang, Depeng; Yu, Honghao; Li, Wenjing

    2013-01-01

    Abstract Li, Hongge, Songchang Guo, Yongming Ren, Depeng Wang, Honghao Yu, Wenjing Li, Xinquan Zhao, and Zhijie Chang. VEGF189 expression is highly related to adaptation of the plateau pika (Ochotona curzoniae) inhabiting high altitudes. High Alt Med Biol 14:395–404, 2013.— The plateau pika (Ochotona curzonia) has adapted to high-altitude hypoxia during evolution. Higher microvessel density in specific tissues and a blunted hypoxic pulmonary vasoconstriction response are the critical components of this adaptation. VEGF, vascular endothelial growth factor, has proved to be a key regulator of angiogenesis in response to tissue hypoxia and to play an important role in vascular vasodilation. However, the role of VEGF in adaptation to high-altitude hypoxia in the plateau pika remains unknown. In this study, we cloned cDNAs for VEGF165 and VEGF189 and examined their expression in pikas inhabiting altitudes of 3200 and 4750 m. Phylogenetic analysis reveals that pika VEGF165 and VEGF189 are evolutionarily conserved. Real-time PCR analysis demonstrates that VEGF165 and VEGF189 display tissue and altitude-specific expression patterns. Interestingly, we found that the levels of VEGF189 mRNA are significantly higher than those of VEGF165 in the brain and muscle tissues of the pika, which is different from what was previously observed in sea-level mammals. VEGF189 mRNA levels in brain, muscle, and lung of the pika increased with increased habitat altitude, whereas VEGF165 shows less change. Our study suggests an important role for VEGF189 in adaptation to hypoxia by the plateau pika in the high-altitude environment. PMID:24377347

  14. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C4 of the Plateau Pika (Ochotona curzoniae)

    PubMed Central

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2016-01-01

    Testis-specific lactate dehydrogenase (LDH-C4) is one of the lactate dehydrogenase (LDH) isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae) belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000–5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A4 (LDH-A4), Lactate Dehydrogenase B4 (LDH-B4), and LDH-C4 were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis (PAGE). The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km) of LDH-C4 for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C4 for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki) of the LDH isoenzymes varied: LDH-A4 (Ki = 26.900 mmol/L), LDH-B4 (Ki = 23.800 mmol/L), and LDH-C4 (Ki = 65.500 mmol/L). These data suggest that inhibition of lactate by LDH-A4 and LDH-B4 were stronger than LDH-C4. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4. PMID:26751442

  15. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C₄ of the Plateau Pika (Ochotona curzoniae).

    PubMed

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2016-01-07

    Testis-specific lactate dehydrogenase (LDH-C₄) is one of the lactate dehydrogenase (LDH) isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C₄ in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae) belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000-5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C₄ in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A₄ (LDH-A₄), Lactate Dehydrogenase B₄ (LDH-B₄), and LDH-C₄ were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis (PAGE). The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km) of LDH-C₄ for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C₄ for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki) of the LDH isoenzymes varied: LDH-A₄ (Ki = 26.900 mmol/L), LDH-B₄ (Ki = 23.800 mmol/L), and LDH-C₄ (Ki = 65.500 mmol/L). These data suggest that inhibition of lactate by LDH-A₄ and LDH-B₄ were stronger than LDH-C₄. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C₄.

  16. VEGF189 expression is highly related to adaptation of the plateau pika (Ochotona curzoniae) inhabiting high altitudes.

    PubMed

    Li, Hongge; Guo, Songchang; Ren, Yongming; Wang, Depeng; Yu, Honghao; Li, Wenjing; Zhao, Xinquan; Chang, Zhijie

    2013-12-01

    The plateau pika (Ochotona curzonia) has adapted to high-altitude hypoxia during evolution. Higher microvessel density in specific tissues and a blunted hypoxic pulmonary vasoconstriction response are the critical components of this adaptation. VEGF, vascular endothelial growth factor, has proved to be a key regulator of angiogenesis in response to tissue hypoxia and to play an important role in vascular vasodilation. However, the role of VEGF in adaptation to high-altitude hypoxia in the plateau pika remains unknown. In this study, we cloned cDNAs for VEGF165 and VEGF189 and examined their expression in pikas inhabiting altitudes of 3200 and 4750 m. Phylogenetic analysis reveals that pika VEGF165 and VEGF189 are evolutionarily conserved. Real-time PCR analysis demonstrates that VEGF165 and VEGF189 display tissue and altitude-specific expression patterns. Interestingly, we found that the levels of VEGF189 mRNA are significantly higher than those of VEGF165 in the brain and muscle tissues of the pika, which is different from what was previously observed in sea-level mammals. VEGF189 mRNA levels in brain, muscle, and lung of the pika increased with increased habitat altitude, whereas VEGF165 shows less change. Our study suggests an important role for VEGF189 in adaptation to hypoxia by the plateau pika in the high-altitude environment.

  17. Biological features of the skin of the pika, Ochotona rufescens rufescens: histological structure and enzymatic histochemical reactivity.

    PubMed

    Sakai, T; Yamada, S; Taniguchi, Y; Kodama, S; Horiuchi, S; Nomura, T

    1987-04-01

    To examine the usefulness of the pika, Ochotona rufescens rufescens, as an experimental animal for skin irritability tests, the histological structure and enzymatic histochemical reactivity of pika skin were investigated. The pika had a hair cycle similar to that of the rabbit. The skin and epidermis of the pika trunk were 1.16mm and 29.5 microns thick, on the average, respectively. Both of them were the thickest in the dorsal region followed by the interscapular area, while they were the thinnest in the abdominal region. In the epidermis of the pika, the strata corneum, granulosum, spinosum and basale were rather clearly distinguished. The cell arrangement in the stratum basale was more compact than that in the rabbit. Dermal mast cells, which are distributed in the stratum reticulare in rabbits and guinea pigs, were distributed in the stratum papillare right beneath the epidermis. The mast cell of the pika in the TEM images had granules of low electron density and with relatively long microvilli and rather large mitochondria. The activities of the enzymes, SDH, MDH, LDH, beta HBDH, alpha GPDH, ALD, G6PDH and GPR, in the hair follicles and sebaceous glands of the pika were similar to those of the rabbit.

  18. A modified enrichment method to construct microsatellite library from plateau pika genome (Ochotona curzoniae).

    PubMed

    Geng, Jianing; Li, Kexin; Zhang, Yanming; Hu, Songnian

    2010-03-01

    A microsatellite-enriched library of plateau pika (Ochotona curzoniae) was constructed according to the strong affinity between biotin and streptavidin. Firstly, genomic DNA was fragmented by ultrasonication, which is a major improvement over traditional methods. Linker-ligated DNA fragments were hybridized with biotinylated microsatellite probes, and then were subjected to streptavidin-coated magnetic beads. PCR amplification was performed to obtain double-stranded DNA fragments containing microsatellites. Ligation and transformation were carried out by using the pGEM-T Vector System I and Escherichia coli DH10B competent cells. Sequencing results showed that 80.2% of clones contained microsatellite repeat motif. Several modifications make this protocol time-efficient and technically easier than the traditional ones; particularly, composition and relative abundance of microsatellite repeats in plateau pika genome were truly represented through the optimized PCR conditions. This method has also been successfully applied to construct microsatellite-enriched genomic libraries of Chinese hamster (Cricetulus griseus) and small abalone [Haliotis diversicolor (Reeve)] with high rates of positive clones, demonstrating its feasibility and stability. 2010 Beijing Genomics Institute. Published by Elsevier Ltd. All rights reserved.

  19. Effects of quinestrol and levonorgestrel on populations of plateau pikas, Ochotona curzoniae, in the Qinghai-Tibetan Plateau.

    PubMed

    Liu, Ming; Qu, Jiapeng; Yang, Min; Wang, Zengli; Wang, Yanling; Zhang, Yanming; Zhang, Zhibin

    2012-04-01

    Plateau pikas (Ochotona curzoniae, Hodgson, 1858) are viewed as a pest in the Tibetan Plateau meadow ecosystem when their population densities are high. Traditional culling using rodenticides often poses a high risk to non-target species and even to humans. In this study, an investigation was made of the infertility effects of quinestrol (E), levonorgestrel (P) and a combination of the two (EP, ratio E:P = 1:2) on plateau pikas during 2007 and 2008. Treatment with E or EP significantly decreased the pregnancy rate of female pikas in 2007. In 2008, there was a cross-year effect that still suppressed male reproduction in treated groups. Treatment with E obviously reduced the reproduction of pikas but not their population abundance in 2007; the reduction in population size was significant in 2008. Single baiting of quinestrol in early breeding season reduced the reproduction and population size of pikas throughout 2007. The effect of infertility lasted into the next breeding season through a cross-year effect, which resulted in a significant reduction of population size in 2008. Quinestrol is a very promising non-lethal approach to managing pika populations; however, several factors need to be investigated further to improve the practicality of this method. Copyright © 2012 Society of Chemical Industry.

  20. Radiocarbon dating of American pika fecal pellets provides insights into population extirpations and climate refugia

    Treesearch

    Constance I. Millar; Katherine Heckman; Christopher Swanston; Karena Schmidt; Robert D. Westfall; Diane L. Delany

    2014-01-01

    The American pika (Ochotona princeps) has become a species of concern for its sensitivity to warm temperatures and potential vulnerability to global warming. We explored the value of radiocarbon dating of fecal pellets to address questions of population persistence and timing of site extirpation. Carbon was extracted from pellets collected at 43...

  1. A surprising discovery of American pika sites in the northwest Great Basin

    Treesearch

    Mackenzie R. Jeffress; K. Jane Van Gunst; Constance I. Millar

    2017-01-01

    Although the American pika (Ochotona princeps) continues to receive attention due to documented declines and range retractions, particularly in the Great Basin, thorough range inventories have yet to be completed in many parts of the region. Here we report on recently discovered populations in northwestern Nevada in areas not suspected to support...

  2. Thermal components of American pika habitat—How does a small lagomorph encounter climate?

    Treesearch

    Connie Millar; Bob Westfall; Diane L. Delany

    2016-01-01

    Anticipating the response of small mammals to climate change requires knowledge of thermal conditions of their habitat during times of the day and year when individuals use them. We measured diurnal and seasonal temperatures of free air and of six habitat components for American pikas (Ochotona princeps) over five years at 37 sites in seven...

  3. Molecular cloning and characterization of hemoglobin alpha and beta chains from plateau pika (Ochotona curzoniae) living at high altitude.

    PubMed

    Yingzhong, Yang; Yue, Cao; Guoen, Jin; Zhenzhong, Bai; Lan, Ma; Haixia, Yun; Rili, Ge

    2007-11-15

    Hemoglobin (Hb) plays an important role in oxygen transfer from lung to tissues. Possession of a Hb with high oxygen affinity helps highland animals to adapt to high altitude, has been studied profoundly. Plateau pika (Ochotona curzoniae), a native species living at 3,000-5,000 m above sea level on Qinghai-Tibet Plateau, is a typical hypoxia and low temperature tolerant mammal. To investigate the possible mechanisms of plateau pika Hb in adaptation to high altitude, the complete cDNA and amino acid sequences of plateau pika hemoglobin alpha and beta chains have been described. Compared with human Hb, alterations in important regions can be noted: alpha111 Ala-->Asn, beta35 Tyr-->Phe, beta112 Cys-->Val, beta115 Ala-->Ser, and beta125 Pro-->Gln. Phylogenetic analysis of alpha and beta chains shows that plateau pika is closer to rabbit than to other species. This study provides essential information for elucidating the possible roles of hemoglobin in adaptation to extremely high altitude in plateau pika.

  4. [Contraction responses of isolated aortic rings of pika (Ochotona curzoniae) and Sprague-Dawley rat to hypoxia].

    PubMed

    Ma, Shuang; Ma, Yan; Ge, Ri-Li

    2013-04-25

    The aim of the present study was to observe the effects of hypoxia on tensions of aortic rings of pika (Ochotona curzoniae) and Sprague-Dawley (SD) rat. The aortic rings were prepared, and in vitro vascular ring perfusion was used to assay the effects of hypoxia or different drugs on contraction responses of the rings with or without endothelium. The results showed that, there was no difference of the contractions to KCl (80 mmol/L) between the aortic rings of the pikas and SD rats. After pre-contraction with NE (1 μmol/L), the aortic rings with endothelium of the SD rats showed obvious relaxation to ACh (1 μmol/L), whereas the aortic rings of the pikas, no matter with or without endothelium, showed significant and unusual contraction to ACh. The aortic rings of pikas, no matter with or without endothelium, exhibited greater contraction when treated by 1 h of hypoxia, compared with those in SD rats; The similar result was showed under hypoxia in combination with Ca(2+) removal. These results suggest that the contraction response to hypoxia in pika is more sensitive compared to that in SD rat, which is dependent on the release of calcium from intracellular calcium store.

  5. Multilocus approaches reveal underestimated species diversity and inter-specific gene flow in pikas (Ochotona) from southwestern China.

    PubMed

    Koju, Narayan Prasad; He, Kai; Chalise, Mukesh Kumar; Ray, Chris; Chen, Zhongzheng; Zhang, Bin; Wan, Tao; Chen, Shunde; Jiang, Xuelong

    2017-02-01

    The phylogeny of living pikas (Ochotonidae, Ochotona) remains obscure, and pika species diversity in southwestern China has never been well explored. In this study, 96 tissue samples from 11 valid species in three classified subgenera (Pika, Ochotona and Conothoa) from 23 locations were characterized using multilocus sequences of 7031bp. Two mitochondrial (CYT B and COI) and five nuclear gene segments (RAG1, RAG2, TTN, OXAIL and IL1RAPL1) were sequenced. We analysed evolutionary histories using maximum likelihood (RAxML) and Bayesian analyses (BEAST), and we also used molecular species delimitation analyses (BPP) to explore species diversity. Our study supported O. syrinx (O. huangensis) as a distinct clade from all named subgenera. Relationships among subgenera were not fully resolved, which may be due to a rapid diversification in the middle Miocene (∼13.90Ma). Conflicting gene trees implied mitochondrial introgression from O. cansus to O. curzoniae. We uncovered three cryptic species from Shaanxi, Sichuan and Yunnan with strong support, suggesting an underestimation of species diversity in the "sky-island" mountains of southwest China.

  6. [Functional difference of malate-aspartate shuttle system in liver between plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae)].

    PubMed

    Zhu, Rui-Juan; Rao, Xin-Feng; Wei, Deng-Bang; Wang, Duo-Wei; Wei, Lian; Sun, Sheng-Zhen

    2012-04-25

    To explore the adaptive mechanisms of plateau zokor (Myospalax baileyi) to the enduring digging activity in the hypoxic environment and of plateau pika (Ochotona curzoniae) to the sprint running activity, the functional differences of malate-aspartate shuttle system (MA) in liver of plateau zokor and plateau pika were studied. The ratio of liver weight to body weight, the parameters of mitochondria in hepatocyte and the contents of lactic acid in serum were measured; the open reading frame of cytoplasmic malate dehydrogenase (MDH1), mitochondrial malate dehydrogenase (MDH2), and the partial sequence of aspartate glutamate carrier (AGC) and oxoglutarate malate carrier (OMC) genes were cloned and sequenced; MDH1, MDH2, AGC and OMC mRNA levels were determined by real-time PCR; the specific activities of MDH1 and MDH2 in liver of plateau zokor and plateau pika were measured using enzymatic methods. The results showed that, (1) the ratio of liver weight to body weight, the number and the specific surface of mitochondria in hepatocyte of plateau zokor were markedly higher than those of plateau pika (P < 0.01 or P < 0.05), but the content of lactic acid in serum of plateau pika was significantly higher than that of plateau zokor (P < 0.01); (2) MDH1 and MDH2 mRNA levels as well as their enzymatic activities in liver of plateau zokor were significantly higher than those of plateau pika (P < 0.01 or 0.05), AGC mRNA level of the zokor was significantly higher than that of the pika (P < 0.01), while no difference was found at OMC mRNA level between them (P > 0.05); (3) mRNA level and enzymatic activity of MDH1 was significantly lower than those of MDH2 in the pika liver (P < 0.01), MDH1 mRNA level of plateau zokor was markedly higher than that of MDH2 (P < 0.01), but the activities had no difference between MDH1 and MDH2 in liver of the zokor (P > 0.05). These results indicate that the plateau zokor obtains ATP in the enduring digging activity by enhancing the function of MA

  7. Effects of temperature and photoperiod on thermogenesis in plateau pikas (Ochotona curzoniae) and root voles (Microtus oeconomus).

    PubMed

    Wang, D; Sun, R; Wang, Z; Liu, J

    1999-02-01

    We examined the effects of temperature and photoperiod on metabolic thermogenesis and the thermogenic characteristics of brown adipose tissue in plateau pikas (Ochotona curzoniae) and root voles (Microtus oeconomus), the dominant species of small mammals in the alpine meadow ecosystems on the Qinghai-Tibetan Plateau. Pikas and voles were acclimated in the following groups: (1) Long day-warm temperature (16L:8D, 23 degrees C) (2) Long day-cold temperature (16L:8D, 5 degrees C), (3) short day-warm temperature (8L:16D, 23 degrees C), and (4) short day-cold temperature (8L:16D, 5 degrees C). Both temperature and photoperiod were important environmental cues for changes in thermogenesis for both species. Low temperature and short photoperiod induced increases in metabolic rate, nonshivering thermogenesis (NST), mitochondrial protein contents of brown adipose tissue, and cytochrome C oxidase activity of brown adipose tissue mitochondria in both species. Plateau pikas were more sensitive to cold (79% of the total NST response) than to short photoperiod (21%), while root voles were more sensitive to short photoperiod (60% of the total NST response) than to cold (40%), although cold clearly enhanced thermogenesis. Their thermogenic characteristics correlated with their preferred habitats: plateau pikas are found mainly in more exposed microhabitats in open sunny meadow, while root voles live in more sheltered microhabitats in relatively closed shrub. Our results also showed that temperature and photoperiod combined induce thermogenic adjustments in both species in seasonal acclimatization in their alpine meadow macrohabitat.

  8. Genetic diversity in Echinococcus shiquicus from the plateau pika (Ochotona curzoniae) in Darlag County, Qinghai, China.

    PubMed

    Fan, Yan-Lei; Lou, Zhong-Zi; Li, Li; Yan, Hong-Bin; Liu, Quan-Yuan; Zhan, Fang; Li, Jian-Qiu; Liu, Cong-Nuan; Cai, Jin-Zhong; Lei, Meng-Tong; Shi, Wan-Gui; Yang, Yu-Rong; McManus, Donald P; Jia, Wan-Zhong

    2016-11-01

    The metacestode of Echinococcus shiquicus has been recorded previously in the lung and liver of its intermediate host, the plateau pika (Ochotona curzoniae), but there is limited information regarding other organ sites. There is also limited evidence of intra-specific genetic variation within E. shiquicus. A PCR-amplified mitochondrial (mt) nad1 gene fragment (approximately 1400bp in size), with unique EcoRI and SspI restriction sites, was used to distinguish cysts or cyst-like lesions of E. shiquicus from E. multilocularis. Then, the complete mt nad1 and cox1 genes for the E. shiquicus isolates were amplified and sequenced. Phylogenetic tree and haplotype network analyses for the isolates were then generated based on a concatenated dataset of the nad1 and cox1 genes using the neighbour-joining (NJ) method and TCS1.21 software. Nineteen of eighty trapped pikas were found to harbor cysts (71 in total) when dissected at the survey site. Seventeen animals had cysts (fertile) present only in the lungs, one animal had fertile cysts in the lungs and spleen, and one individual had an infertile kidney cyst. Restriction endonuclease analysis of a fragment of the nad1 gene indicated all the cysts were due to E. shiquicus. Genetic diversity analysis revealed that the nad1 and cox1 genes varied by 0.1-1.2% and 0.1-1.0%, respectively. Haplotype network analysis of the concatenated nad1 and cox1 sequences of the isolates showed they were classified into at least 6 haplotypes, and different haplotype percentages ranged from 4.2% to 29.6%. Although, high haplotype diversity was evident in the study area, the complete nad1 and cox1 gene sequences obtained indicated that all samples represented isolates of E. shiquicus. The study has also provided a new PCR-restriction endonuclease-based method to rapidly distinguish E. shiquicus from E. multilocularis which provides a useful tool for epidemiological investigations where the two species overlap. Copyright © 2016. Published by

  9. Shiga Toxin-Producing Escherichia coli in Plateau Pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau, China.

    PubMed

    Bai, Xiangning; Zhang, Wang; Tang, Xinyuan; Xin, Youquan; Xu, Yanmei; Sun, Hui; Luo, Xuelian; Pu, Ji; Xu, Jianguo; Xiong, Yanwen; Lu, Shan

    2016-01-01

    Shiga toxin-producing Escherichia coli (STEC) are an emerging group of zoonotic pathogens. Ruminants are the natural reservoir of STEC. In this study we determined the prevalence and characteristics of the STEC in plateau pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau, China. A total of 1116 pika samples, including 294 intestinal contents samples, 317 fecal samples, and 505 intestinal contents samples, were collected from May to August in the years 2012, 2013, and 2015, respectively. Twenty-one samples (1.88%) yielded at least one STEC isolate; in total, 22 STEC isolates were recovered. Thirteen different O serogroups and 14 serotypes were identified. One stx 1 subtype (stx 1a) and three stx 2 subtypes (stx 2a, stx 2b, and stx 2d) were present in the STEC isolates. Fifteen, fourteen, and three STEC isolates harbored the virulence genes ehxA, subA, and astA, respectively. Adherence-associated genes iha and saa were, respectively, present in 72.73 and 68.18% of the STEC isolates. Twenty antibiotics were active against all the STEC isolates; all strains were resistant to penicillin G, and some to cephalothin or streptomycin. The 22 STEC isolates were divided into 16 pulsed-field gel electrophoresis patterns and 12 sequence types. Plateau pikas may play a role in the ongoing circulation of STEC in the Qinghai-Tibetan plateau. This study provides the first report on STEC in plateau pikas and new information about STEC reservoirs in wildlife. Based on the serotypes, virulence gene profiles and multi-locus sequence typing (MLST) analysis, the majority of these pika STECs may pose a low public health risk.

  10. [Difference in oxygen uptake in skeletal muscles between plateau zokor (Myospalax rufescens baileyi) and plateau pika (Ochotona curzoniac)].

    PubMed

    Zhu, Shi-Hai; Qi, Xin-Zhang; Wang, Xiao-Jun; Rao, Xin-Feng; Wei, Lian; Wei, Deng-Bang

    2009-08-25

    To investigate the difference between the functions of oxygen uptake in skeletal muscle and living habits of plateau zokor (Myospalax rufescens baileyi) and plateau pika (Ochotona curzoniac), the microvessel densities (MVD) of skeletal muscle of plateau zokor, plateau pika and Sprague-Dawley (SD) rat were measured by immunohistochemical staining; the numerical density on area (N(A)) of mitochondria, and surface density (S(V), external surface area density of mitochondria per unit volume of skeletal muscle fiber) were obtained by stereo microscope technique; mRNA levels of myoglobin (Mb) in skeletal muscle were determined by real-time PCR, and the contents of Mb protein in skeletal muscle were determined by spectro-photometer. The results showed that MVD, N(A) and S(V) of mitochondria in skeletal muscle of plateau pika were significantly lower than those of plateau zokor and SD rat (P<0.05). The mRNA levels of Mb gene in skeletal muscle of plateau zokor and plateau pika were notably higher than that of SD rat (P<0.05). There were significant differences in the contents of Mb among these three species, and plateau zokor and SD rat presented the highest and the lowest value, respectively (P<0.05). The results suggest that even though plateau zokor inhabits in the hypoxia environment, most of its skeletal muscle fiber are red muscle fiber. While most of skeletal muscle fibers of plateau pika are white muscle fibers. This kind of white muscle has low MVD, N(A) and S(V) of mitochondria and less content of Mb compared with the red one, suggesting it obtains most energy from aerobic oxidation. The above-mentioned differences in skeletal muscles may be related to not only the different species, but also the different living habits of these two high altitude species.

  11. Shiga Toxin-Producing Escherichia coli in Plateau Pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau, China

    PubMed Central

    Bai, Xiangning; Zhang, Wang; Tang, Xinyuan; Xin, Youquan; Xu, Yanmei; Sun, Hui; Luo, Xuelian; Pu, Ji; Xu, Jianguo; Xiong, Yanwen; Lu, Shan

    2016-01-01

    Shiga toxin-producing Escherichia coli (STEC) are an emerging group of zoonotic pathogens. Ruminants are the natural reservoir of STEC. In this study we determined the prevalence and characteristics of the STEC in plateau pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau, China. A total of 1116 pika samples, including 294 intestinal contents samples, 317 fecal samples, and 505 intestinal contents samples, were collected from May to August in the years 2012, 2013, and 2015, respectively. Twenty-one samples (1.88%) yielded at least one STEC isolate; in total, 22 STEC isolates were recovered. Thirteen different O serogroups and 14 serotypes were identified. One stx1 subtype (stx1a) and three stx2 subtypes (stx2a, stx2b, and stx2d) were present in the STEC isolates. Fifteen, fourteen, and three STEC isolates harbored the virulence genes ehxA, subA, and astA, respectively. Adherence-associated genes iha and saa were, respectively, present in 72.73 and 68.18% of the STEC isolates. Twenty antibiotics were active against all the STEC isolates; all strains were resistant to penicillin G, and some to cephalothin or streptomycin. The 22 STEC isolates were divided into 16 pulsed-field gel electrophoresis patterns and 12 sequence types. Plateau pikas may play a role in the ongoing circulation of STEC in the Qinghai-Tibetan plateau. This study provides the first report on STEC in plateau pikas and new information about STEC reservoirs in wildlife. Based on the serotypes, virulence gene profiles and multi-locus sequence typing (MLST) analysis, the majority of these pika STECs may pose a low public health risk. PMID:27047483

  12. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    Treesearch

    Joseph A. E. Stewart; David H. Wright; Katherine A. Heckman; Robert Guralnick

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species' core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps...

  13. The earliest occurrence of the steppe pika (Ochotona pusilla) in Europe near the Pliocene/Pleistocene boundary.

    PubMed

    Fostowicz-Frelik, Lucja; Frelik, Grzegorz J

    2010-03-01

    The steppe pika (Ochotona pusilla), a representative of the lagomorph family Ochotonidae, is restricted today to Kazakhstan and Russia. This subspecies-rich form belongs to a morphologically distinct, monospecific group of relatively small pikas, inhabiting steppe-like habitat. In the fossil record, it serves as a bioindicator of dry, grassland environment. The steppe pika was abundant and widespread in Europe during the Last Glaciation, and its unquestionable presence has been reported there since the middle Pleistocene. A new discovery of O. pusilla, from the Kielniki 3B locality (Poland), dated to the latest Pliocene, moves back the species appearance in Europe about one million years, almost coeval with its first record from the late Pliocene of Kazakhstan. Presence of such a typical steppe inhabitant as O. pusilla indicates significant climate change towards more arid, continental conditions, which started influencing Europe at 2.6 Ma. We present the first reliable record of the earliest O. pusilla entry deep into Europe in the latest Pliocene.

  14. The earliest occurrence of the steppe pika ( Ochotona pusilla) in Europe near the Pliocene/Pleistocene boundary

    NASA Astrophysics Data System (ADS)

    Fostowicz-Frelik, Łucja; Frelik, Grzegorz J.

    2010-03-01

    The steppe pika ( Ochotona pusilla), a representative of the lagomorph family Ochotonidae, is restricted today to Kazakhstan and Russia. This subspecies-rich form belongs to a morphologically distinct, monospecific group of relatively small pikas, inhabiting steppe-like habitat. In the fossil record, it serves as a bioindicator of dry, grassland environment. The steppe pika was abundant and widespread in Europe during the Last Glaciation, and its unquestionable presence has been reported there since the middle Pleistocene. A new discovery of O. pusilla, from the Kielniki 3B locality (Poland), dated to the latest Pliocene, moves back the species appearance in Europe about one million years, almost coeval with its first record from the late Pliocene of Kazakhstan. Presence of such a typical steppe inhabitant as O. pusilla indicates significant climate change towards more arid, continental conditions, which started influencing Europe at 2.6 Ma. We present the first reliable record of the earliest O. pusilla entry deep into Europe in the latest Pliocene.

  15. Leptin cDNA cloning and its mRNA expression in plateau pikas (Ochotona curzoniae) from different altitudes on Qinghai-Tibet Plateau.

    PubMed

    Yang, J; Zhao, X Q; Guo, S C; Li, H G; Qi, D L; Wang, D P; Cao, J H

    2006-07-14

    Leptin, an adipocyte-derived hormone, plays an important role in body energy homeostasis. Plateau pika (Ochotona curzoniae), an endemic and keystone species living only at 3000-5000 m above sea level on Qinghai-Tibet Plateau, is a typically high hypoxia and low temperature tolerant mammal with high resting metabolic rate (RMR), non-shivering thermogenesis (NST), and high ratio of oxygen utilization to cope with harsh plateau environment. To explore the molecular mechanism of ecological acclimation in plateau pika, we first cloned pika leptin cDNA and compared its mRNA expression in different altitudes (3200 and 3900 m) using real-time RT-PCR (Taqman probe) technology. The full-length pika leptin cDNA was 3015 with 504 bp open-reading frame encoding the precursor peptide of 167 amino acids including 21 residues of signal peptide. Pika leptin was 70-72% homologous to that of other species and was of similarly structural characteristics with other species. The pika-specific genetic diversity in leptin sequence occurred at twenty sites. With the increase in altitude, there were larger fat store and high level of ob gene expression in plateau pika. Our results indicated that leptin is sensitive to cold and hypoxia plateau environment and may play one of important roles in pika's ecological adaptation to harsh plateau environment.

  16. The protein level of hypoxia-inducible factor-1alpha is increased in the plateau pika (Ochotona curzoniae) inhabiting high altitudes.

    PubMed

    Li, Hong-Ge; Ren, Yong-Ming; Guo, Song-Chang; Cheng, Long; Wang, De-Peng; Yang, Jie; Chang, Zhi-Jie; Zhao, Xin-Quan

    2009-02-01

    The plateau pika (Ochotona curzoniae) is a high hypoxia-tolerant species living only at 3,000-5,000 m above sea-level on the Qinghai-Tibetan plateau. Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor that regulates a variety of cellular and systemic adaptations to hypoxia. To investigate how the plateau pika adapts to a high-altitude hypoxic environment at the molecular level, we examined the expression pattern of the HIF-1alpha protein in the pika by Western blot and immunohistochemical analysis. We found that HIF-1alpha protein is expressed at a significantly high level in the pika, which is higher in most tissues (particularly in the lung, liver, spleen and kidney) of the plateau pika than that of mice living at sea-level. Importantly, we found that the protein levels of HIF-1alpha in the lung, liver, spleen and kidney of the pika were increased with increased habitat altitudes. We observed that the plateau pika HIF-1alpha localized to the nucleus of cells by an immunostaining analysis, and enhanced HRE-driven gene expression by luciferase reporter assays. Our study suggests that the HIF-1alpha protein levels are related to the adaptation of the plateau pika to the high-altitude hypoxic environment.

  17. Feeding and excretion in the Afghan pika (Ochotona rufescens rufescens), a new laboratory animal.

    PubMed

    Matsuzawa, T; Nakata, M; Tsushima, M

    1981-10-01

    Food and water intake and the excretion of urine and faecal pellets during the day (0500-2100) and at night (2100-0500) were observed in Afghan pikas, rats and guineapigs fed appropriate diets. Urine composition was observed in these species after they had been fed the pika diet for 4 weeks. Rats ate more at night than did pikas or guineapigs. The pikas excreted numerous small, hard faeces and soft faeces, the latter being reingested. On the pika diet all species gained about 10% in bodyweight. Food consumption was similar to that shown by each species on its own diet. All animals fed the pika diet excreted alkaline urine. Chloride concentration in pika urine was similar to that of the rat and was significantly higher than that of the guineapig. The ratio of sodium to potassium in pika urine was 2.8 and 1.7 fold that of the rat and guineapig respectively. Osmolality of pika urine was slightly higher than that of the rat, and was 3.8 fold that of the guineapig.

  18. The expression of Ldh-c in the skeletal muscle of plateau pika (Ochotona curzoniae) enhances adaptation to a hypoxic environment.

    PubMed

    An, Zhi F; Wei, Deng B; Wei, Lian; Wang, Yang; Wei, Lin N

    2017-09-15

    The plateau pika (Ochotona curzoniae) is a species of sprint-running alpine animals in the Qinghai-Tibet Plateau, which is a harsh highland hypoxic environment. Ldh-c is expressed in the testis, sperm and somatic tissues of plateau pika. To reveal the role and physiological mechanisms of sperm-specific lactate dehydrogenase (LDH-C4), in plateau pika to adapt to hypoxic environment, an adenoviral line of pMultiRNAi-Ldhc was constructed and injected into the bilateral biceps femoris of the hind legs. The swimming times of the pikas, and the Ldh-c expression levels, total LDH activities and ATP levels in skeletal muscle, were measured after the pikas were raised in the trapped site for 5 days. Our results showed that after Ldh-c was silenced, the sprint-running ability (swimming time) of the plateau pikas was significant decreased, and the total LDH activities and ATP levels were reduced by 28.21% and 27.88%, respectively. Our results indicated that expression of Ldh-c in the skeletal muscle of plateau pika increased anaerobic glycolysis and enhanced adaptation to highland hypoxic environments. © 2017. Published by The Company of Biologists Ltd.

  19. Intermittent cold exposure results in visceral adipose tissue "browning" in the plateau pika (Ochotona curzoniae).

    PubMed

    Bai, Zhenzhong; Wuren, Tana; Liu, Shou; Han, Shirui; Chen, Lin; McClain, Donald; Ge, Ri-Li

    2015-06-01

    The plateau pika has developed tolerance to cold and hypoxia in order to adapt to living in the extreme environment of the Qinghai-Tibetan Plateau. One mammalian mechanism for cold adaptation is thermogenesis by brown adipose tissue (BAT), but the degree to which pika exploits this mechanism or how it may be modified by the additional stresses of high altitude is not known. Intermittent Cold Exposure (ICE) is an approachable method to study cold adaptation in rodents. To investigate the role of adipose tissue in the adaptation of pika to cold temperatures, we have studied pika during ICE. We find that pika kept in warm temperatures has little classical brown fat, but "browning" of white adipose tissues is observed rapidly upon cold exposure. This is demonstrated by the increased expression of several markers of brown fat differentiation including uncoupling protein 1 (UCP-1). Surprisingly, this occurs mainly in visceral rather than epididymal adipose tissue. In addition, ICE increases the expression of several general adipose differentiation markers at both the mRNA and protein levels. These substantial changes in the distribution of fat are accomplished without changes in weight or blood levels of glucose and triglycerides, suggesting that the adaptable changes are coordinated and self-compensated. Together, our results demonstrate that ICE promotes recruitment of BAT in pika, and unlike small mammals in at lower altitudes, pika can activate visceral WAT to adapt to cold stress without major changes overall energy balance. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Cardiac adaptation to high altitude in the plateau pika (Ochotona curzoniae).

    PubMed

    Pichon, Aurélien; Zhenzhong, Bai; Marchant, Dominique; Jin, Guoen; Voituron, Nicolas; Haixia, Yun; Favret, Fabrice; Richalet, Jean-Paul; Ge, Ri-Li

    2013-07-01

    The aim of this study was to assess maximal heart rate (HR) and heart morphological changes in high altitude living "plateau pikas" and rats bred at 2260 m. Rats and pikas were catheterized to measure HR (2260 m). After baseline measurements, 1 mg/kg of atropine (AT) and increasing doses of isoproterenol (IsoP) (0.1, 1, 10, and 100 μg kg) were injected into animals. Right (RV) and left ventricles (LV) were removed to calculate Fulton's ratio (LV + septum (S) to RV weights) and to assess mRNA expression level of β1- and β2-adrenoceptors, muscarinic m1 and m2 receptors, and vascular endothelial growth factor (VEGF). Resting HR was significantly lower in rats than in pikas and increased after AT injection only in rats. IsoP injection induced a significant increase in HR in rat for all doses, which was systematically greater than in pikas. In pikas HR was slightly increased only after the two highest concentrations of IsoP. Fulton's ratio was greater in rats compared with pikas but the LV + S adjusted for body weight was greater in pikas. Pikas showed lower β1-adrenoceptors and muscarinic m2 receptors mRNA expression but larger VEGF mRNA expression than rats both in RV and LV. These results suggest that pikas have a lower maximal HR compared with rats certainly due to a decrease in β-adrenergic and muscarinic receptors mRNA expression. However, the LV hypertrophy probably led to an increase in stroke volume to maintain cardiac output in response to the cold and hypoxic environment.

  1. Blunted hypoxic pulmonary vasoconstrictive response in the rodent Ochotona curzoniae (pika) at high altitude.

    PubMed

    Ge, R L; Kubo, K; Kobayashi, T; Sekiguchi, M; Honda, T

    1998-05-01

    To investigate the possible mechanisms of adaptation to chronic hypoxia in the pulmonary circulation, we made direct measurements of pulmonary arterial pressure (Ppa) in 10 awake pika rodents that were transported to Xining, People's Republic of China (altitude 2,260 m) after being captured at 4,300 m and in 10 Wistar rats in a decompression chamber (simulated altitudes of 4,300 and 5,000 m) in Xining. Ppa was obtained at 1 h of exposure to each simulated altitude. The histology and immunohistochemistry of the lung tissues were also studied. Ppa in the pikas after the 4,300- and 5,000-m altitude exposures did not significantly increase, whereas in the rats Ppa rose significantly. Mean changes in Ppa from 2,260 to 4,300 and 5,000 m were 1.48 +/- 0.49 and 4.80 +/- 0.67 mmHg in the pikas and 10.38 +/- 3.36 and 19.10 +/- 2.28 mmHg in the rats. The ratio of right ventricular to left ventricular plus septal weight in the pikas and rats was 0.22 and 0.45, respectively. The pikas maintained levels of Hb, hematocrit, and 2,3-diphosphoglycerate lower than those of the rats. The percent wall thickness of the small pulmonary arteries in the pikas and rats was 9.22 and 27.21%, respectively, and it was well correlated with the degree of Ppa in both groups. Mast cells were observed in the lungs of the rats (7.1 +/- 0.33 cells/mm2) but not in the pikas. There was highly positive staining for mast cell tryptase and transforming growth factor-beta around pulmonary vessels in the rats, whereas no demonstrable reaction was observed in the pikas. We conclude that the pika has adapted to high altitude by losing hypoxic pulmonary vasoconstriction and thin-walled pulmonary arterioles.

  2. Morphological characteristics of the intestinal mucosa in the Afghan pika (Ochotona rufescens rufescens).

    PubMed

    Kurohmaru, M; Hayakawa, T; Seki, M; Zyo, K

    1984-10-01

    The intestinal mucosa of the pika was examined with the naked eyes, a light microscope and a scanning electron microscope and was compared with that of the rabbit. The duodenal mucosa of the rabbit showed wavy folds different from so-called villi, while that of the pika exhibited leaf-like or columnar villi. In addition to the specific ileocecal lymphoid apparatuses, the pika had the peculiar region between the cecum and the proximal colon. That region called "the constricted portion" possessed characteristic net-arranged folds and well-developed muscular layers. At the lateral surface of these folds, small villus-like protrusions projected into the lumen in large numbers. The spiral fold ran around the mucosal surface of the rabbit cecum, whereas numerous slender protrusions, cecal digitations, projected into the lumen of the pika cecum. Although the colon of the pika showed a similar external figure to that of the rabbit, some differences were obviously found in histological structures. The first segment of the pika proximal colon with three teniae possessed several protrusions and well-developed mucous glands, while that of the rabbit had neither protrusions nor mucous glands. The second segment of the pika proximal colon with one tenia was covered with numerous villus-like protrusions, while that of the rabbit was composed of wart-like protrusions. The tubular mucous glands were observed in the lamina propria of the pika as well as the rabbit. The distal colon of the pika showed a flat mucosal surface and possessed tubular mucous glands as observed in the rabbit.

  3. Spontaneous closure of isolated ventricular septal defect in the pika (Ochotona rufescens rufescens).

    PubMed

    Shinohara, H; Nishimura, H

    1986-04-01

    The incidence of spontaneously occurring ventricular septal defects (VSD) in PIKA neonates and its fate during development are investigated. A total of 160 PIKAs were used in the present study. They consisted of three groups; first, 56 live neonates, second, 37 3-week-old live animals and third, 68 animals which had died during the first two weeks after birth from unknown causes. As high as 8.9% (5 cases out of 56) of the live neonates revealed isolated ventricular septal defects of membranous type. Decreased incidence (2.7%) was seen in 3-week-old PIKAs. Its implication and significance are evaluated in the discussion.

  4. Cardiac adaptation to high altitude in the plateau pika (Ochotona curzoniae)

    PubMed Central

    Pichon, Aurélien; Zhenzhong, Bai; Marchant, Dominique; Jin, Guoen; Voituron, Nicolas; Haixia, Yun; Favret, Fabrice; Richalet, Jean-Paul; Ge, Ri-Li

    2013-01-01

    The aim of this study was to assess maximal heart rate (HR) and heart morphological changes in high altitude living “plateau pikas” and rats bred at 2260 m. Rats and pikas were catheterized to measure HR (2260 m). After baseline measurements, 1 mg/kg of atropine (AT) and increasing doses of isoproterenol (IsoP) (0.1, 1, 10, and 100 μg kg) were injected into animals. Right (RV) and left ventricles (LV) were removed to calculate Fulton's ratio (LV + septum (S) to RV weights) and to assess mRNA expression level of β1- and β2-adrenoceptors, muscarinic m1 and m2 receptors, and vascular endothelial growth factor (VEGF). Resting HR was significantly lower in rats than in pikas and increased after AT injection only in rats. IsoP injection induced a significant increase in HR in rat for all doses, which was systematically greater than in pikas. In pikas HR was slightly increased only after the two highest concentrations of IsoP. Fulton's ratio was greater in rats compared with pikas but the LV + S adjusted for body weight was greater in pikas. Pikas showed lower β1-adrenoceptors and muscarinic m2 receptors mRNA expression but larger VEGF mRNA expression than rats both in RV and LV. These results suggest that pikas have a lower maximal HR compared with rats certainly due to a decrease in β-adrenergic and muscarinic receptors mRNA expression. However, the LV hypertrophy probably led to an increase in stroke volume to maintain cardiac output in response to the cold and hypoxic environment. PMID:24303117

  5. Morphological and molecular characterization of Oestromyia leporina (Pallas, 1778) (Diptera: Hypodermatinae) from wild plateau pikas(Ochotona curzoniae) in Qinghai province, China.

    PubMed

    Fu, Yong; Li, Wei; Duo, Hong; Guo, Zhihong; Dang, Zhisheng; Shen, Xiuying; Peng, Mao; Zhang, Yanming

    2016-02-01

    The objective of this article was to investigate the morphological and molecular characterization of Oestromyia leporina (Pallas, 1778) from wild plateau pikas (Ochotona curzoniae) in Qinghai province, China. The third-stage larvae of O. leporina were examined by scanning electron microscopy revealing morphology characteristics of the spines on the cephalic, the thoracic segments, the abdominal segments and the spiracular plates. The coding regions of 25 cytochrome oxidase I (COI) genes of O. leporina were investigated. Eighty-one variable sites and 21 haplotypes were identified and the nucleotide and haplotype diversities were 0.04456 and 0.9767, respectively, indicating a rich genetic diversity in O. leporina. Phylogenetic analysis utilizing sequences of COI revealed two distinct lineages. These findings revealed ultrastructure and molecular characterization among the O. leporina from plateau pikas in Qinghai province, China and had implications for studying morphological identification, molecular epidemiology and population genetics of O. leporina. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Cloning of hypoxia-inducible factor 1alpha cDNA from a high hypoxia tolerant mammal-plateau pika (Ochotona curzoniae).

    PubMed

    Zhao, T B; Ning, H X; Zhu, S S; Sun, P; Xu, S X; Chang, Z J; Zhao, X Q

    2004-04-02

    Hypoxia-inducible factor 1 is a transcription factor composed of HIF-1alpha and HIF-1beta. It plays an important role in the signal transduction of cell response to hypoxia. Plateau pika (Ochotona curzoniae) is a high hypoxia-tolerant and cold adaptation species living only at 3000-5000 m above sea level on the Qinghai-Tibet Plateau. In this study, HIF-1alpha cDNA of plateau pika was cloned and its expression in various tissues was studied. The results indicated that plateau pika HIF-1alpha cDNA was highly identical to those of the human (82%), bovine (89%), mouse (82%), and Norway rat (77%). The deduced amino acid sequence (822bp) showed 90%, 92%, 86%, and 86% identities with those of the human, bovine, house mouse, and Norway rat, respectively. Northern blot analyses detected two isoforms named pLHIF-1alpha and pSHIF-1alpha. The HIF-1alpha mRNA was highly expressed in the brain and kidney, and much less in the heart, lung, liver, muscle, and spleen, which was quite different from the expression pattern of mouse mRNA. Meanwhile, a new variant of plateau pika HIF-1alpha mRNA was identified by RT-PCR and characterized. The deduced protein, composed of 536 amino acids, lacks a part of the oxygen-dependent degradation domain (ODD), both transactivation domains (TADs), and the nuclear localization signal motif (NLS). Our results suggest that HIF-1alpha may play an important role in the pika's adaptation to hypoxia, especially in brain and kidney, and pika HIF-1alpha function pattern may be different from that of mouse HIF-1alpha. Furthermore, for the high ratio of HIF-1alpha homology among the animals, the HIF-1alpha gene may be a good phylogenetic performer in recovering the true phylogenetic relationships among taxa.

  7. [The expression of the sperm-specific lactate dehydrogenase gene Ldh-c in plateau pika (Ochotona curzoniae) cardiac muscle and its effect on the anaerobic glycolysis].

    PubMed

    Li, Xiao; Wei, Lian; Wang, Yang; Xu, Li-Na; Wei, Lin-Na; Wei, Deng-Bang

    2015-06-25

    The plateau pika (Ochotona curzoniae) has a strong adaptability to hypoxic plateau environment. We found that the sperm-specific lactate dehydrogenase (LDH-C4) gene Ldh-c expressed in plateau pika cardiac muscle. In order to shed light on the effect of LDH-C4 on the anaerobic glycolysis in plateau pika cardiac muscle, 20 pikas were randomly divided into the inhibitor group and the control group, and the sample size of each group was 10. The pikas of inhibitor group were injected with 1 mL 1 mol/L N-isopropyl oxamate, a specific LDH-C4 inhibitor, in biceps femoris muscle of hind legs, each leg with 500 μL. The pikas of control group were injected with the same volume of normal saline (0.9% NaCl). The mRNA and protein expression levels of Ldh-c gene in plateau pika cardiac muscle were determined by real-time PCR and Western blot. The activities of LDH, and the contents of lactate (LD) and ATP in cardiac muscle were compared between the inhibitor group and the control group. The results showed that 1) the expression levels of Ldh-c mRNA and protein were 0.47 ± 0.06 and 0.68 ± 0.08, respectively; 2) 30 min after injection of 1 mL 1 mol/L N-isopropyl oxamate in biceps femoris muscle, the concentration of N-isopropyl oxamate in blood was 0.08 mmol/L; 3) in cardiac muscle of the inhibitor group and the control group, the LDH activities were (6.18 ± 0.48) U/mg and (9.08 ± 0.58) U/mg, the contents of LD were (0.21 ± 0.03) mmol/g and (0.26 ± 0.04) mmol/g, and the contents of ATP were (4.40 ± 0.69) nmol/mg and (6.18 ± 0.73) nmol/mg (P < 0.01); 5) the inhibition rates of N-isopropyl oxamate to LDH, LD and ATP were 31.98%, 20.90% and 28.70%, respectively. The results suggest that Ldh-c expresses in cardiac muscle of plateau pika, and the pika cardiac muscle may get at least 28% ATP for its activities by LDH-C4 catalyzed anaerobic glycolysis, which reduces the dependence on oxygen and enhances the adaptation to the hypoxic environments.

  8. Immunohistochemical and ultrastructural study of anterior pituitary cells in the female Afghan pika, Ochotona rufescens rufescens.

    PubMed

    Nakamura, F; Suzuki, Y; Yoshimura, F

    1986-01-01

    An immunohistochemical study of the anterior pituitary gland of the female Afghan pika was carried out to distinguish the ultrastructural features of GH, PRL, ACTH, TSH and LH cells. The histochemically identified GH cells resembled ultrastructurally oval or round GH cells of the rat laden with large, dense secretory granules. PRL cells were divided into three subtypes based on differences in the diameter of their spherical secretory granules. They lacked polymorphic or irregularly shaped secretory granules. ACTH cells resembled ultrastructurally, in some respects, Siperstein's "corticotrophs" of the rat with peripheral arrangement of secretory granules. However, they were not always stellate, but elongate or angular in shape. The dense secretory granules were concentrated in the peripheral area of cytoplasm. TSH cells were non-stellate, but usually oval in shape, containing the smallest spherical secretory granules (100-200 nm in diameter). Almost all LH cells reacted also with FSH antiserum. They were irregular in shape, sometimes in contact with or surrounded the GH cells. They contained an abundance of medium-sized secretory granules (140-260 nm in diameter) which were larger than those in the LH cells of the female rat throughout the estrous cycle. Large secretory granules in the LH cells of the female pika seemed to be related to the endocrine state of persistent estrus.

  9. Mycoplasma lagogenitalium sp. nov., from the preputial smegma of Afghan pikas (Ochotona rufescens rufescens).

    PubMed

    Kobayashi, H; Runge, M; Schmidt, R; Kubo, M; Yamamoto, K; Kirchhoff, H

    1997-10-01

    Organisms with characteristics typical of mycoplasmas were isolated from the preputial smegma of Afghan picas (Ochotona rufescens rufescens). The results of growth inhibition tests, metabolic inhibition tests, and immunobinding assays showed that the isolated strains were identical and that they were distinct from previously described Mycoplasma, Entomoplasma, Mesoplasma, and Acholeplasma species. These organisms represent a new species, for which the name Mycoplasma lagogenitalium is proposed. M. lagogenitalium ferments glucose, does not hydrolyze arginine or urea, reduces tetrazolium chloride, possesses phosphatase activity, does not digest gelatin or casein, and does not produce films or spots. It lyses sheep erythrocytes and does not adsorb sheep, rabbit, or horse erythrocytes. Cholesterol or serum is required for growth. The growth temperature is 37 degrees C. The guanine-plus-cytosine content of the DNA is 23.0 +/- 1.0 mol%. The type strain is M. lagogenitalium 12MS (= ATCC 700289T).

  10. A morphological study of the retinal ganglion cells of the Afghan pika (Ochotona rufescens).

    PubMed

    Akaishi, Y; Uchiyama, H; Ito, H; Shimizu, Y

    1995-03-01

    The distribution and morphology of the retinal ganglion cells was studied in a relative of the rabbit, the Afghan pika. The total number of retinal ganglion cells was approximately 170,000. The total number of optic nerve fibers was between 160,000 and 190,000, corresponding to the total number of retinal ganglion cells. Retinal ganglion cells were found to have a horizontal region of high-density. The maximum density was 5250 cells/mm2. This region was located in the central retina below the optic disc. This area contained numerous closely packed small ganglion cells, while the peripheral retina (especially in the dorsal periphery) contained large ganglion cells more loosely dispersed. The retinal ganglion cells labeled by horseradish peroxidase (HRP) were morphologically classified into three types based on dendritic length and ramification pattern.

  11. Differences of glycolysis in skeletal muscle and lactate metabolism in liver between plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae).

    PubMed

    Sun, Sheng-Zhen; Wei, Lian; Wei, Deng-Bang; Wang, Duo-Wei; Ma, Ben-Yuan

    2013-06-25

    The plateau pika (Ochotona curzoniae) and plateau zokor (Myospalax baileyi) are specialized native species of the Qinghai-Tibetan plateau. The goal of this study was to examine physiological differences in skeletal muscle glycolysis and hepatic lactate metabolism between these two species. The partial sequence of pyruvate carboxylase (PC) gene was cloned and sequenced. The mRNA expression levels of PC and lactate dehydrogenases (LDH-A, LDH-B) were determined by real-time PCR. The enzymatic activity of PC was measured using malic acid coupling method. The concentration of lactic acid (LD) and the specific activities of LDH in liver and skeletal muscle of two species were measured. The different isoenzymes of LDH were determined by native polyacrylamide gel electrophoresis (PAGE). The results showed that, (1) LDH-B mRNA level in skeletal muscle of plateau zokor was significantly higher than that of plateau pika (P < 0.01), but no differences was found at LDH-A mRNA levels between them (P > 0.05); (2) PC, LDH-A and LDH-B mRNA levels in liver of plateau pika were significantly higher than those of plateau zokor (P < 0.01); (3) The LDH activity and concentration of LD in skeletal muscle and liver, as well as the PC activity in liver of plateau pika were significantly higher than those of plateau zokor (P < 0.01); (4) The isoenzymatic spectrum of lactate dehydrogenase showed that the main LDH isoenzymes were LDH-A4, LDH-A3B and LDH-A2B2 in skeletal muscle of plateau pika, while the main LDH isoenzymes were LDH-AB3 and LDH-B4 in skeletal muscle of plateau zokor; the main isoenzymes were LDH-A3B, LDH-A2B2, LDH-AB3 and LDH-B4 in liver of plateau pika, while LDH-A4 was the only isoenzyme in liver of plateau zokor. These results indicate that the plateau pika gets most of its energy for sprint running through enhancing anaerobic glycolysis, producing more lactate in their skeletal muscle, and converting lactate into glucose and glycogen in the liver by enhancing

  12. Effect of the disturbance of plateau pika (Ochotona curzoniae) on soil water and soil temperature characteristics at Alpine Meadows in Qinghai-Tibet Plateau, China

    NASA Astrophysics Data System (ADS)

    Ma, Yujun; Wu, Yinan; Wang, Xiaoxing; Li, Xiaoyan

    2015-04-01

    The plateau pika (Ochotona curzoniae) is one of main small rodents at Alpine Meadows in Qinghai-Tibet Plateau, and has a positive effect on the maintenance of regional soil biodiversity. But, its excessive disturbance was also known as an important factor that leads to the vegetation degradation. Based on the field experiment, sampling analysis and continuous observation, this study compared the difference of soil water and soil temperature characteristics at different disturbance stages, which included native grassland, new mound, old mound and bare land formed by old mound. The findings of this study revealed that, after the disturbance of plateau pika, the soil bulk density at the shallow layer (0-20 cm) increased with the time-lapse. At the 20-30 cm depth, the soil bulk density of old mound, bare land and native grassland were similar, and were all higher than that of new mound. At the deep layer (under 30 cm), the soil bulk density had no significant difference between four stages, which showed that the disturbance of plateau pika mainly distributed within the shallow 30 cm depth. The unsaturated hydraulic conductivity of new mound was higher than old mound, bare soil and native grassland, with the multiple of 3.08-8.71, 4.63-16.27 and 3.70-15.25, respectively, and led to the obvious variance of soil water change for different types of land surface. After the precipitation, the soil water content change of new mound and old mound were more significant than that of bare land and native grassland. Because of the disturbance of plateau pika, the soil temperature characteristics changed, too. The heat conductivity rate of new mound and old mound decreased, significantly, and their daily temperature difference were obvious higher than bare land and native grassland. These results were essential for the study of vegetation recovery after the disturbance of plateau pika.

  13. Fine structure of the mandibular gland in pika (Ochotona rufescens rufescens).

    PubMed

    Suzuki, S; Ago, A; Nishinakagawa, H; Otsuka, J

    1985-07-01

    The mandibular gland of the pika was examined by light microscopy, and transmission and scanning electron microscopies. The acinar cells were noted to be composed of serous cells and seromucous cells. The serous cells containing granules of moderate and high densities were slightly basophile and strongly positive to PAS, but were not stained with AB. The seromucous cells possessing less dense granules were light and moderately positive to PAS and AB. A sexual dimorphism was observed between these cells: Serous cells were considerably more frequent in males and seromucous cells were more numerous in females. Intercalated duct cells consisted of cuboidal light cells containing a few vesicles in the apical region. Striated ducts were comprised of two portions--a secretory portion and a typical striated portion without secretory granules. The secretory portion was composed of light and dark cells having secretory granules varying in size and density. The epithelium of typical striated portion consisted of light and dark cells containing fine vacuoles and vesicles.

  14. Inhibition of inducible nitric oxide synthase expression and nitric oxide production in plateau pika (Ochotona curzoniae) at high altitude on Qinghai-Tibet Plateau.

    PubMed

    Xie, Ling; Zhang, Xuze; Qi, Delin; Guo, Xinyi; Pang, Bo; Du, Yurong; Zou, Xiaoyan; Guo, Songchang; Zhao, Xinquan

    2014-04-30

    Nitric oxide (NO), a potent vasodilator, plays an important role in preventing hypoxia induced pulmonary hypertension. Endogenous NO is synthesized by nitric oxide synthases (NOSs) from l-arginine. In mammals, three different NOSs have been identified, including neuronal NOS (nNOS), endothelial NOS (eNOS) and inducible NOS (iNOS). Plateau pika (Ochotona curzoniae) is a typical hypoxia tolerant mammal that lives at 3000-5000 m above sea level on the Qinghai-Tibet Plateau. The aim of this study was to investigate whether NOS expression and NO production are regulated by chronic hypoxia in plateau pika. Quantitative real-time PCR and western blot analyses were conducted to quantify relative abundances of iNOS and eNOS transcripts and proteins in the lung tissues of plateau pikas at different altitudes (4550, 3950 and 3200 m). Plasma NO metabolites, nitrite/nitrate (NO(x)⁻) levels were also examined by Ion chromatography to determine the correlation between NO production and altitude level. The results revealed that iNOS transcript levels were significantly lower in animals at high altitudes (decreased by 53% and 57% at altitude of 3950 and 4550 m compared with that at 3200 m). Similar trends in iNOS protein abundances were observed (26% and 41% at 3950 and 4550 m comparing with at 3200 m). There were no significant differences in eNOS mRNA and protein levels in the pika lungs among different altitudes. The plasma NO(x)⁻ levels of the plateau pikas at high altitudes significantly decreased (1.65±0.19 μg/mL at 3200 m to 0.44±0.03 μg/mL at 3950 m and 0.24±0.01 μg/mL at 4550 m). This is the first evidence describing the effects of chronic hypoxia on NOS expression and NO levels in the plateau pika in high altitude adaptation. We conclude that iNOS expression and NO production are suppressed at high altitudes, and the lower NO concentration at high altitudes may serve crucial roles for helping the plateau pika to survive at hypoxic environment. Copyright © 2014

  15. Eimeria spp. (Apicomplexa: Eimeriidae) from the Plateau pika, Ochotona curzoniae, from Haibei Area, Qinghai Province, China, with the description of two new species.

    PubMed

    Cao, Yi-Fan; Ye, Run-Roung; Wu, Jian-Hua; Bian, Jiang-Hui; Duszynski, Donald W

    2009-10-01

    Fifty-two fecal samples from the Plateau pika, Ochotona curzoniae, collected in the Haibei Area, Qinghai Province, China, were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Five distinct morphotypes, all Eimeria species, were distinguished based on the structure of their sporulated oocysts. Three of these included Eimeria banffensis, Eimeria calentinei, and Eimeria cryptobarretti, all of which have been described previously from other Ochotona species. We also studied 2 morphotypes that we feel have sufficient qualitative and quantitative characters to distinguish them from all previously described species; herein, we identify them as putative new species. Eimeria qinghaiensis n.sp. was found in 18/52 (35%) O. curzoniae. It has ovoidal oocysts with a 3-layered wall, with a rough outermost layer and a micropyle, approximately 9 microm wide. Sporulated oocysts are 37.2 x 27.2 (34-41 x 24-32) microm; 1 polar granule is present, but an oocyst residuum is absent. Sporocysts are ovoidal, 16.6 x 9.8 (14-19 x 9-11) microm with a Stieda body; sporocyst residuum and sporozoites have 2 refractile bodies. Eimeria haibeiensis n. sp. was found in 21/52 (40%) pikas. It has ellipsoidal to ovoidal oocysts, with a 2-layered smooth wall and a micropyle, 3.9 microm wide. Oocysts are 22.2 x 16.2 (20-24 x 15-18) microm; polar granule and oocyst residuum are both absent. Sporocysts are ovoidal, 11.6 x 6.6 (10-13 x 5-7) microm, with a Stieda body; sporocyst residuum and sporozoites each have 2 refractile bodies, 1 at each end. The 5 eimerian species we discovered in O. curzoniae in China all represent new host and locality records.

  16. Rodent-Pika Parasite Spillover in Western North America.

    PubMed

    Foley, Patrick; Roth, Tara; Foley, Janet; Ray, Chris

    2017-09-01

    Competition during the Cenozoic expansion of the Rodentia may have contributed to ecological niche reduction of pikas, which are now increasingly under threat as their habitat degrades under global climate change, while some rodents expand their ranges and overlap with pikas. Range overlap carries the possibility of disease spillover. Contemporary North American pikas are cold-adapted and relegated primarily to alpine environments where they subsist on relatively low-quality herbaceous diet. Yet their evolutionary ancestors were distributed geographically even into the subtropics. Here we examine historical and contemporary records of fleas on pikas (Ochotona princeps) from sites at different elevations in the Sierra Nevada and Rocky Mountains and the Pacific Northwest. We calculated indices of diversity from each site and spillover fraction, i.e., the proportion of fleas on pikas that have a preference for rodents. Across this range there are four pika specialist flea species, with no more than two of these per site, and 18 characteristically rodent flea species. Diversity is greatest in the Pacific Northwest and lowest in Montana. Rodent flea spillover onto pikas declines with elevation in the Rocky Mountains. These data provide evidence that rodents and pikas interact enough to allow considerable parasite spillover, and which could be exacerbated as pikas are increasingly stressed by climate change at lower elevations some rodent species expand up-elevation in the face of increasing global warming. With global climate change, both biotic and abiotic niche shrinkage demand our attention. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. American pika in a low-elevation lava landscape: expanding the known distribution of a temperature-sensitive species

    PubMed Central

    Shinderman, Matt

    2015-01-01

    In 2010, the American pika (Ochotona princeps fenisex) was denied federal protection based on limited evidence of persistence in low-elevation environments. Studies in nonalpine areas have been limited to relatively few environments, and it is unclear whether patterns observed elsewhere (e.g., Bodie, CA) represent other nonalpine habitats. This study was designed to establish pika presence in a new location, determine distribution within the surveyed area, and evaluate influences of elevation, vegetation, lava complexity, and distance to habitat edge on pika site occupancy. In 2011 and 2012, we conducted surveys for American pika on four distinct subalpine lava flows of Newberry National Volcanic Monument, Oregon, USA. Field surveys were conducted at predetermined locations within lava flows via silent observation and active searching for pika sign. Site habitat characteristics were included as predictors of occupancy in multinomial regression models. Above and belowground temperatures were recorded at a subsample of pika detection sites. Pika were detected in 26% (2011) and 19% (2012) of survey plots. Seventy-four pika were detected outside survey plot boundaries. Lava complexity was the strongest predictor of pika occurrence, where pika were up to seven times more likely to occur in the most complicated lava formations. Pika were two times more likely to occur with increasing elevation, although they were found at all elevations in the study area. This study expands the known distribution of the species and provides additional evidence for persistence in nonalpine habitats. Results partially support the predictive occupancy model developed for pika at Craters of the Moon National Monument, another lava environment. Characteristics of the lava environment clearly influence pika site occupancy, but habitat variables reported as important in other studies were inconclusive here. Further work is needed to gain a better understanding of the species’ current

  18. WHY MUSEUMS MATTER: A TALE OF PINWORMS (OXYUROIDEA: HETEROXYNEMATIDAE) AMONG PIKAS (OCHOTONA PRINCEPS AND O. COLLARIS) IN THE AMERICAN WEST.

    USDA-ARS?s Scientific Manuscript database

    Permanent and well supported museum collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characterist...

  19. Lowly pathogenic avian influenza (H9N2) infection in Plateau pika (Ochotona curzoniae), Qinghai Lake, China.

    PubMed

    Yu, Zhijun; Cheng, Kaihui; Sun, Weiyang; Xin, Yue; Cai, Jinshan; Ma, Ruilin; Zhao, Quanbang; Li, Lin; Huang, Jing; Sang, Xiaoyu; Li, Xue; Zhang, Kun; Wang, Tiecheng; Qin, Chuan; Qian, Jun; Gao, Yuwei; Xia, Xianzhu

    2014-09-17

    Avian influenza viruses (AIVs) are globally important contagions. Several domestic mammals can be infected with AIVs and may play important roles in the adaptation and transmission of these viruses in mammals, although the roles of wild mammals in the natural ecology of AIVs are not yet clear. Here, we performed a serological survey of apparently healthy Plateau pikas at Qinghai Lake in China to assess the prevalence of exposure to AIVs. Ninety-two of 293 (31%) of wild Plateau pikas possessed serum antibodies against a lowly pathogenic avian influenza (LPAI) H9N2 virus. Experimental inoculation of Plateau pikas with a LPAI H9N2 virus resulted in productive viral replication in respiratory tissues without prior adaptation. Our findings suggest that Plateau pikas represent a natural mammalian host to H9N2 AIVs and may play a role in the ongoing circulation of H9N2 viruses at Qinghai Lake in China. Surveillance for AIV infection in Plateau pika populations and other mammals that have close contact with the Plateau pikas should be considered. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. [Biological features of the skin of the pika, Ochotona rufescens rufescens--concentration of histamine in the skin].

    PubMed

    Kodama, Y; Sakai, T; Naitou, K; Horiuchi, S

    1990-07-01

    The quantity of histamine and the number of mast cells in the skin of the pika were measured and compared with rabbits, guinea pigs and rats. The ranking of regional histamine levels in the skin of the pika was: perianal region greater than abdomen greater than interscapular region = back greater than lumbus greater than head greater than auricle, and the average value of the 7 regions was 22.6 micrograms/g. The level of histamine in the 6 regions, except the auricle, was 2-5 times that of rabbits and guinea pigs. In the auricle of each of the 4 kinds of animal (pika, rabbit, guinea pig and rat), the levels were almost identical. With respect to histamine levels, those in the pika resembled those in rats. The number of mast cells in the skin of the pika was less than in rats, and was greater than that in rabbits and guinea pigs. The average value was 9.9/mm2.

  1. [Induction of cutaneous or subcutaneous fibroblastic tumors in the Afghan pika (Ochotona rufescens rufescens) by injection or bovine papilloma virus].

    PubMed

    Puget, A; Favre, M; Orth, G

    1975-06-23

    Newborn Afghan pikas have been inoculated with bovine papilloma virus via the subcutaneous route. Cutaneous or subcutaneous fibromas and fibrosarcomas were observed after a mean incubation period of nine months. The transmission of these tumors by homograft has been obtained. Bovine papilloma virus antibodies have been demonstrated in most of the animals inoculated at birth. They have not been detected in animals bearing transplanted tumors.

  2. Colonization from divergent ancestors: glaciation signatures on contemporary patterns of genomic variation in Collared Pikas (Ochotona collaris).

    PubMed

    Lanier, Hayley C; Massatti, Rob; He, Qixin; Olson, Link E; Knowles, L Lacey

    2015-07-01

    Identifying the genetic structure of a species and the factors that drive it is an important first step in modern population management, in part because populations evolving from separate ancestral sources may possess potentially different characteristics. This is especially true for climate-sensitive species such as pikas, where the delimitation of distinct genetic units and the characterization of population responses to contemporary and historical environmental pressures are of particular interest. We combined a restriction site-associated DNA sequencing (RADSeq) data set containing 4156 single nucleotide polymorphisms with ecological niche models (ENMs) of present and past habitat suitability to characterize population composition and evaluate the effects of historical range shifts, contemporary climates and landscape factors on gene flow in Collared Pikas, which are found in Alaska and adjacent regions of northwestern Canada and are the lesser-studied of North America's two pika species. The results suggest that contemporary environmental factors contribute little to current population connectivity. Instead, genetic diversity is strongly shaped by the presence of three ancestral lineages isolated during the Pleistocene (~148 and 52 kya). Based on ENMs and genetic data, populations originating from a northern refugium experienced longer-term stability, whereas both southern lineages underwent population expansion - contradicting the southern stability and northern expansion patterns seen in many other taxa. Current populations are comparable with respect to generally low diversity within populations and little-to-no recent admixture. The predominance of divergent histories structuring populations implies that if we are to understand and manage pika populations, we must specifically assess and accurately account for the forces underlying genetic similarity. © 2015 John Wiley & Sons Ltd.

  3. Ochotona(Lagomorpha) from Late Quaternary Cave Deposits in Eastern North America

    NASA Astrophysics Data System (ADS)

    Mead, Jim I.; Grady, Frederick

    1996-01-01

    Pikas ( Ochtona)—small gnawing mammals, related to rabbits—range today throughout parts of the Northern Hemisphere, but had a wider distribution during the Pleistocene. Nine caves from northeastern North America (a region not occupied by pikas today) have Pleistocene deposits containing remains of Ochotona.We examine 526 fossil specimens (ranging in age from approximately 850,000 to 8670 yr B.P.) from five of these caves. Two morphological forms of Ochotonalived in northeastern North America during the late Pleistocene—a large species (probably O. whartoni) and a small species (probably O. princeps). Ochotonaof glacial age are not necessarily indicative of talus slopes and mesic communities. O. princeps-like of the Irvingtonian of West Virginia were living with an amphibian-reptilian assemblage found in the area today, implying winters not much, if at all, colder than at present. Late glacial and postglacial change in climate south of the ice sheets in effect would have isolated Ochotonain eastern North America, where they were unable to retreat to the west or north. Whereas western pika had the option of moving up in elevation, into boreal islands, eastern forms became restricted to ever-diminishing habitats, culminating in extinction and extirpation. Radiocarbon ages imply that Ochotonalived in eastern North America during the late Pleistocene (late Rancholabrean) and into the earliest Holocene. We describe the youngest remains of Ochotonain eastern North America and the youngest for the extinct large form, O. whartoni.

  4. Individual-based analysis of hair corticosterone reveals factors influencing chronic stress in the American pika.

    PubMed

    Waterhouse, Matthew D; Sjodin, Bryson; Ray, Chris; Erb, Liesl; Wilkening, Jennifer; Russello, Michael A

    2017-06-01

    Glucocorticoids are often measured in wildlife to assess physiological responses to environmental or ecological stress. Hair, blood, saliva, or fecal samples are generally used depending on the timescale of the stress response being investigated and species-specific considerations. Here, we report the first use of hair samples to measure long-term corticosterone levels in the climate-sensitive American pika (Ochotona princeps). We validated an immunoassay-based measurement of corticosterone extracted from hair samples and compared corticosterone estimates obtained from plasma, hair, and fecal samples of nine pikas. To demonstrate an ecological application of this technique, we characterized physiological stress in 49 pikas sampled and released at eight sites along two elevational transects. Microclimate variation was measured at each site using both ambient and subsurface temperature sensors. We used an information theoretic approach to compare support for linear, mixed-effects models relating corticosterone estimates to microclimate, body size, and sex. Corticosterone was measured accurately in pika hair samples after correcting for the influence of sample mass on corticosterone extraction efficiency. Hair- and plasma-based estimates of corticosterone were weakly correlated. The best-supported model suggested that corticosterone was lower in larger, male pikas, and at locations with higher ambient temperatures in summer. Our results are consistent with a general negative relationship between body mass and glucocorticoid concentration observed across mammalian species, attributed to the higher mass-specific metabolic rates of smaller bodied animals. The higher corticosterone levels in female pikas likely reflected the physiological demands of reproduction, as observed in a wide array of mammalian species. Additionally, we establish the first direct physiological evidence for thermal stress in the American pika through nonlethal sampling of corticosterone

  5. Long-term ventilatory adaptation and ventilatory response to hypoxia in plateau pika (Ochotona curzoniae): role of nNOS and dopamine.

    PubMed

    Pichon, Aurélien; Zhenzhong, Bai; Favret, Fabrice; Jin, Guoen; Shufeng, Han; Marchant, Dominique; Richalet, Jean-Paul; Ge, Ri-Li

    2009-10-01

    We assessed ventilatory patterns and ventilatory responses to hypoxia (HVR) in high-altitude (HA) plateau pikas, repetitively exposed to hypoxic burrows, and control rats. We evaluated the role of neuronal nitric oxide synthase (nNOS) and dopamine by using S-methyl-l-thiocitrulline (SMTC) inhibitor and haloperidol antagonist, respectively. Ventilation (Vi) was measured using a whole body plethysmograph in conscious pikas (n = 9) and low-altitude (LA) rats (n = 7) at different Pi(O(2)) (56, 80, 111, 150, and 186 mmHg) and in HA acclimatized rats (n = 9, 8 days at 4,600 m) at two different Pi(O(2)) (56 and 80 mmHg). The effects of NaCl, SMTC, and haloperidol on ventilatory patterns were assessed in pikas at Pi(O(2)) = 56 and 80 mmHg. We observed a main species effect with larger Vi, tidal volume (VT), inspiratory time/total time (T(i)/T(tot)), and a lower expiratory time in pikas than in LA rats. Pikas had also a larger VT and lower respiratory frequency compared with HA rats in hypoxia. HVR of pikas and rats were not statistically different. In pikas, SMTC induced a significant increase in Vi and VT for a Pi(O(2)) of 56 mmHg, but had no effect for a PiO(2) of 80 mmHg, i.e., the living altitude of pikas. In pikas, haloperidol injection had no effect on any ventilatory parameter. Long-term ventilatory adaptation in pikas is mainly due to an improvement in respiratory pattern (VT and T(i)/T(tot)) with no significant improvement in HVR. The sensitivity to severe acute hypoxia in pikas seems to be regulated by a peripheral nNOS mechanism.

  6. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA.

    PubMed

    Stewart, Joseph A E; Wright, David H; Heckman, Katherine A

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species' core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km2 area located within its core habitat in California's Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancy ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910-2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades.

  7. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    PubMed Central

    Wright, David H.; Heckman, Katherine A.

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species’ core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km2 area located within its core habitat in California’s Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancy ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910–2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades. PMID:28854268

  8. Pseudogenization of CCL14 in the Ochotonidae (pika) family.

    PubMed

    Neves, Fabiana; Abrantes, Joana; Lissovsky, Andrey A; Esteves, Pedro José

    2015-08-01

    The interaction between chemokines and their receptors is crucial for inflammatory cell trafficking. CCL14 binds with high affinity to CCR5. In leporids, CCR5 underwent gene conversion with CCR2. The study of CCR5 ligands in leporid species showed that CCL8 is pseudogenized, while CCL3, CCL4 and CCL5 are functional. Here, we study the evolution of CCL14 in mammals with emphasis in the order Lagomorpha. By employing maximum likelihood methods we detected six sites under positive selection. Some of these sites are located in regions crucial for CCL14 activation and binding to receptors. Sequencing of CCL14 in Ochotona species showed that O. princeps, O. pallasi, O. alpina and O. turuchanensis have a mutation at the start codon (Met > Thr), while O. hoffmanni, O. mantchurica, O. dauurica and O. rufescens present the mammalian conserved Met. Ochotona hyperborea has the two alleles. In O. pusilla, CCL14 is a pseudogene due to a seven base pair insertion. Like CCL3, CCL4 and CCL5, CCL14 is functional in all leporids but in the Ochotonidae family it underwent a pseudogenization process. This suggests that CCL14 has an important biological role in other mammals by evolving under positive selection that has been lost in Ochotonidae (subgenera Pika and Lagotona).

  9. An eco-evolutionary IBM improves predictions of future geneticconnectivity for American Pikas (Ochotona princeps) in Crater Lake National Park, Oregon

    EPA Science Inventory

    In the face of rapid, contemporary climate change, conservationbiologists are relying heavily on species distribution models (SDMs)to predict shifting occupancy and distribution patterns in responseto future conditions. These models are critical tools for assessingvulnerability t...

  10. An eco-evolutionary IBM improves predictions of future geneticconnectivity for American Pikas (Ochotona princeps) in Crater Lake National Park, Oregon

    EPA Science Inventory

    In the face of rapid, contemporary climate change, conservationbiologists are relying heavily on species distribution models (SDMs)to predict shifting occupancy and distribution patterns in responseto future conditions. These models are critical tools for assessingvulnerability t...

  11. Determinants of pika population density vs. occupancy in the Southern Rocky Mountains.

    PubMed

    Erb, Liesl P; Ray, Chris; Guralnick, Robert

    2014-04-01

    Species distributions are responding rapidly to global change. While correlative studies of local extinction have been vital to understanding the ecological impacts of global change, more mechanistic lines of inquiry are needed for enhanced forecasting. The current study assesses whether the predictors of local extinction also explain population density for a species apparently impacted by climate change. We tested a suite of climatic and habitat metrics as predictors of American pika (Ochotona princeps) relative population density in the Southern Rocky Mountains, USA. Population density was indexed as the density of pika latrine sites. Negative binomial regression and AICc showed that the best predictors of pika latrine density were patch area followed by two measures of vegetation quality: the diversity and relative cover of forbs. In contrast with previous studies of habitat occupancy in the Southern Rockies, climatic factors were not among the top predictors of latrine density. Populations may be buffered from decline and ultimately from extirpation at sites with high-quality vegetation. Conversely, populations at highest risk for declining density and extirpation are likely to be those in sites with poor-quality vegetation.

  12. Novel genomic resources for a climate change sensitive mammal: characterization of the American pika transcriptome

    PubMed Central

    2013-01-01

    Background When faced with climate change, species must either shift their home range or adapt in situ in order to maintain optimal physiological balance with their environment. The American pika (Ochotona princeps) is a small alpine mammal with limited dispersal capacity and low tolerance for thermal stress. As a result, pikas have become an important system for examining biotic responses to changing climatic conditions. Previous research using amplified fragment length polymorphisms (AFLPs) has revealed evidence for environmental-mediated selection in O. princeps populations distributed along elevation gradients, yet the anonymity of AFLP loci and lack of available genomic resources precluded the identification of associated gene regions. Here, we harnessed next-generation sequencing technology in order to characterize the American pika transcriptome and identify a large suite of single nucleotide polymorphisms (SNPs), which can be used to elucidate elevation- and site-specific patterns of sequence variation. Results We constructed pooled cDNA libraries of O. princeps from high (1400m) and low (300m) elevation sites along a previously established transect in British Columbia. Transcriptome sequencing using the Roche 454 GS FLX titanium platform generated 780 million base pairs of data, which were assembled into 7,325 high coverage contigs. These contigs were used to identify 24,261 novel SNP loci. Using high resolution melt analysis, we developed 17 of these SNPs into genotyping assays, which were validated with independent DNA samples from British Columbia Canada and Oregon State USA. In addition, we detected haplotypes in the NADH dehydrogenase subunit 5 of the mitochondrial genome that were fixed and different among elevations, suggesting that this may be an informative target gene for studying the role of cellular respiration in local adaptation. We also identified contigs that were unique to each elevation, including a high elevation-specific contig that was

  13. Novel genomic resources for a climate change sensitive mammal: characterization of the American pika transcriptome.

    PubMed

    Lemay, Matthew A; Henry, Philippe; Lamb, Clayton T; Robson, Kelsey M; Russello, Michael A

    2013-05-10

    When faced with climate change, species must either shift their home range or adapt in situ in order to maintain optimal physiological balance with their environment. The American pika (Ochotona princeps) is a small alpine mammal with limited dispersal capacity and low tolerance for thermal stress. As a result, pikas have become an important system for examining biotic responses to changing climatic conditions. Previous research using amplified fragment length polymorphisms (AFLPs) has revealed evidence for environmental-mediated selection in O. princeps populations distributed along elevation gradients, yet the anonymity of AFLP loci and lack of available genomic resources precluded the identification of associated gene regions. Here, we harnessed next-generation sequencing technology in order to characterize the American pika transcriptome and identify a large suite of single nucleotide polymorphisms (SNPs), which can be used to elucidate elevation- and site-specific patterns of sequence variation. We constructed pooled cDNA libraries of O. princeps from high (1400 m) and low (300 m) elevation sites along a previously established transect in British Columbia. Transcriptome sequencing using the Roche 454 GS FLX titanium platform generated 780 million base pairs of data, which were assembled into 7,325 high coverage contigs. These contigs were used to identify 24,261 novel SNP loci. Using high resolution melt analysis, we developed 17 of these SNPs into genotyping assays, which were validated with independent DNA samples from British Columbia Canada and Oregon State USA. In addition, we detected haplotypes in the NADH dehydrogenase subunit 5 of the mitochondrial genome that were fixed and different among elevations, suggesting that this may be an informative target gene for studying the role of cellular respiration in local adaptation. We also identified contigs that were unique to each elevation, including a high elevation-specific contig that was a positive match

  14. Mechanistic variables can enhance predictive models of endotherm distributions: the American pika under current, past, and future climates.

    PubMed

    Mathewson, Paul D; Moyer-Horner, Lucas; Beever, Erik A; Briscoe, Natalie J; Kearney, Michael; Yahn, Jeremiah M; Porter, Warren P

    2017-03-01

    How climate constrains species' distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models (SDMs), mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika (Ochotona princeps) as an example, we present a framework whereby mechanism can be incorporated into endotherm SDMs. Pika distribution has repeatedly been found to be constrained by warm temperatures, so we used Niche Mapper, a mechanistic heat-balance model, to convert macroclimate data to pika-specific surface activity time in summer across the western United States. We then explored the difference between using a macroclimate predictor (summer temperature) and using a mechanistic predictor (predicted surface activity time) in SDMs. Both approaches accurately predicted pika presences in current and past climate regimes. However, the activity models predicted 8-19% less habitat loss in response to annual temperature increases of ~3-5 °C predicted in the region by 2070, suggesting that pikas may be able to buffer some climate change effects through behavioral thermoregulation that can be captured by mechanistic modeling. Incorporating mechanism added value to the modeling by providing increased confidence in areas where different modeling approaches agreed and providing a range of outcomes in areas of disagreement. It also provided a more proximate variable relating animal distribution to climate, allowing investigations into how unique habitat characteristics and intraspecific phenotypic variation may allow pikas to exist in areas outside those predicted by generic SDMs. Only a small number of easily obtainable data are required to parameterize this mechanistic model for any endotherm, and its use can improve SDM predictions by explicitly modeling a widely applicable direct physiological effect

  15. Mechanistic variables can enhance predictive models of endotherm distributions: The American pika under current, past, and future climates

    USGS Publications Warehouse

    Mathewson, Paul; Moyer-Horner, Lucas; Beever, Erik; Briscoe, Natalie; Kearney, Michael T; Yahn, Jeremiah; Porter, Warren P.

    2017-01-01

    How climate constrains species’ distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models (SDMs), mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika (Ochotona princeps) as an example, we present a framework whereby mechanism can be incorporated into endotherm SDMs. Pika distribution has repeatedly been found to be constrained by warm temperatures, so we used Niche Mapper, a mechanistic heat-balance model, to convert macroclimate data to pika-specific surface activity time in summer across the western United States. We then explored the difference between using a macroclimate predictor (summer temperature) and using a mechanistic predictor (predicted surface activity time) in SDMs. Both approaches accurately predicted pika presences in current and past climate regimes. However, the activity models predicted 8–19% less habitat loss in response to annual temperature increases of ~3–5 °C predicted in the region by 2070, suggesting that pikas may be able to buffer some climate change effects through behavioral thermoregulation that can be captured by mechanistic modeling. Incorporating mechanism added value to the modeling by providing increased confidence in areas where different modeling approaches agreed and providing a range of outcomes in areas of disagreement. It also provided a more proximate variable relating animal distribution to climate, allowing investigations into how unique habitat characteristics and intraspecific phenotypic variation may allow pikas to exist in areas outside those predicted by generic SDMs. Only a small number of easily obtainable data are required to parameterize this mechanistic model for any endotherm, and its use can improve SDM predictions by explicitly modeling a widely applicable direct physiological effect

  16. Landscape effects on gene flow for a climate-sensitive montane species, the American pika.

    PubMed

    Castillo, Jessica A; Epps, Clinton W; Davis, Anne R; Cushman, Samuel A

    2014-02-01

    Climate change is arguably the greatest challenge to conservation of our time. Most vulnerability assessments rely on past and current species distributions to predict future persistence but ignore species' abilities to disperse through landscapes, which may be particularly important in fragmented habitats and crucial for long-term persistence in changing environments. Landscape genetic approaches explore the interactions between landscape features and gene flow and can clarify how organisms move among suitable habitats, but have suffered from methodological uncertainties. We used a landscape genetic approach to determine how landscape and climate-related features influence gene flow for American pikas (Ochotona princeps) in Crater Lake National Park. Pikas are heat intolerant and restricted to cool microclimates; thus, range contractions have been predicted as climate changes. We evaluated the correlation between landscape variables and genetic distance using partial Mantel tests in a causal modelling framework, and used spatially explicit simulations to evaluate methods of model optimization including a novel approach based on relative support and reciprocal causal modelling. We found that gene flow was primarily restricted by topographic relief, water and west-facing aspects, suggesting that physical restrictions related to small body size and mode of locomotion, as well as exposure to relatively high temperatures, limit pika dispersal in this alpine habitat. Our model optimization successfully identified landscape features influencing resistance in the simulated data for this landscape, but underestimated the magnitude of resistance. This is the first landscape genetic study to address the fundamental question of what limits dispersal and gene flow in the American pika. © 2014 John Wiley & Sons Ltd.

  17. Sex differences in the ontogeny of social behavior in pikas: possible relationships to dispersal and territoriality

    USGS Publications Warehouse

    1984-01-01

    A laboratory study on the ontogeny of social behavior in pikas (Ochotona princeps), an alpine lagomorph, was conducted to determine the role of early relationships between adult females and young and among siblings in the development of territorial and dispersal behaviors. Sex differences during development were examined because field studies have reported greater dispersal distances in young females than young males. At birth, females were significantly heavier than males. There were no sex differences in nursing frequency until after the 2nd week of age, when males initiated more nursing attempts than females. By the end of the weaning period (weeks 5 and 6), adult females became non-interactive with young, but aggression of young toward littermates and the mother increased until the eighth week. At this time, young males outweighed their sibling females. Young were dominant over their mothers by the age of 5 weeks, and young males were dominant over their sibling females. Sex differences were observed in aggression, scent-marking, exploratory activity, and submissive vocalizations, with higher rates in young males, except for submissive vocalizations, which were higher in females (Table 2). Vocalizations and scent-marking behavior increased over time, and were positively correlated with interaction rates. These data support the hypothesis that female young disperse farther than male young largely as the result of unsuccessful competition with male siblings for available territories close to the birthplace. A dispersal strategy for pikas is proposed.

  18. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    DOE PAGES

    Stewart, Joseph A. E.; Wright, David H.; Heckman, Katherine A.

    2017-08-30

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species’ core habitat has been lacking. Here in this paper, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km2 area located within its core habitat in California’s Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancy rangesmore » from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910–2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades.« less

  19. The idiosyncrasies of place: geographic variation in the climate-distribution relationships of the American pika.

    PubMed

    Jeffress, Mackenzie R; Rodhouse, Thomas J; Ray, Chris; Wolff, Susan; Epps, Clinton W

    2013-06-01

    Although climate acts as a fundamental constraint on the distribution of organisms, understanding how this relationship between climate and distribution varies over a species' range is critical for addressing the potential impacts of accelerated climate change on biodiversity. Bioclimatic niche models provide compelling evidence that many species will experience range shifts under scenarios of global change, yet these broad, macroecological perspectives lack specificity at local scales, where unique combinations of environment, biota, and history conspire against generalizations. We explored how these idiosyncrasies of place affect the climate-distribution relationship of the American pika (Ochotona princeps) by replicating intensive field surveys across bioclimatic gradients in eight U.S. national parks. At macroecological scales, the importance of climate as a constraint on pika distribution appears unequivocal; forecasts suggest that the species' range will contract sharply in coming decades. However, the species persists outside of its modeled bioclimatic envelope in many locations, fueling uncertainty and debate over its conservation status. Using a Bayesian hierarchical approach, we modeled variation in local patterns of pika distribution along topographic position, vegetation cover, elevation, temperature, and precipitation gradients in each park landscape. We also accounted for annual turnover in site occupancy probabilities. Topographic position and vegetation cover influenced occurrence in all parks. After accounting for these factors, pika occurrence varied widely among parks along bioclimatic gradients. Precipitation by itself was not a particularly influential predictor. However, measures of heat stress appeared most influential in the driest parks, suggesting an interaction between the strength of climate effects and the position of parks along precipitation gradients. The combination of high elevation, cold temperatures, and high precipitation

  20. Genetic characterization of H9N2 avian influenza virus in plateau pikas in the Qinghai Lake region of China.

    PubMed

    Yan, Yan; Gu, Jin-Yan; Yuan, Zhuang-Chuan; Chen, Xin-Yu; Li, Zeng-Kui; Lei, Jing; Hu, Bo-Li; Yan, Li-Ping; Xing, Gang; Liao, Min; Zhou, Ji-Yong

    2017-04-01

    Qinghai Lake is a major migratory-bird breeding site that has experienced several highly pathogenic avian influenza virus (AIV) epizootics. Plateau pikas (Ochotona curzoniae) have previously been implicated in the ecology of avian influenza virus in this region. We first isolated an H9N2 AIV (A/Pika/Menyuan/01/2008) from plateau pikas between November 2008 and October 2009. Sequence analysis showed that the A/Pika/Menyuan/01/2008 AIV was closely related to the H9N2 AIV strain (A/Turkey/Wisconsin/ 1/1966). Our findings suggested that plateau pikas may contribute to AIV epidemiology in the Qinghai Lake region.

  1. Pika Gut May Select for Rare but Diverse Environmental Bacteria

    PubMed Central

    Li, Huan; Li, Tongtong; Yao, Minjie; Li, Jiabao; Zhang, Shiheng; Wirth, Stephan; Cao, Weidong; Lin, Qiang; Li, Xiangzhen

    2016-01-01

    The composition of the mammalian gut bacterial communities can be influenced by the introduction of environmental bacteria in their respective habitats. However, there are no extensive studies examining the interactions between environmental bacteriome and gut bacteriome in wild mammals. Here, we explored the relationship between the gut bacterial communities of pika (Ochotona spp.) and the related environmental bacteria across host species and altitudinal sites using 16S rRNA gene sequencing. Plateau pikas (O. curzoniae) and Daurian pikas (O. daurica) were sampled at five different sites, and plant and soil samples were collected at each site as well. Our data indicated that Plateau pikas and Daurian pikas had distinct bacterial communities. The pika, plant and soil bacterial communities were also distinct. Very little overlap occurred in the pika core bacteria and the most abundant environmental bacteria. The shared OTUs between pikas and environments were present in the environment at relatively low abundance, whereas they were affiliated with diverse bacterial taxa. These results suggested that the pika gut may mainly select for low-abundance but diverse environmental bacteria in a host species-specific manner. PMID:27582734

  2. Pika Gut May Select for Rare but Diverse Environmental Bacteria.

    PubMed

    Li, Huan; Li, Tongtong; Yao, Minjie; Li, Jiabao; Zhang, Shiheng; Wirth, Stephan; Cao, Weidong; Lin, Qiang; Li, Xiangzhen

    2016-01-01

    The composition of the mammalian gut bacterial communities can be influenced by the introduction of environmental bacteria in their respective habitats. However, there are no extensive studies examining the interactions between environmental bacteriome and gut bacteriome in wild mammals. Here, we explored the relationship between the gut bacterial communities of pika (Ochotona spp.) and the related environmental bacteria across host species and altitudinal sites using 16S rRNA gene sequencing. Plateau pikas (O. curzoniae) and Daurian pikas (O. daurica) were sampled at five different sites, and plant and soil samples were collected at each site as well. Our data indicated that Plateau pikas and Daurian pikas had distinct bacterial communities. The pika, plant and soil bacterial communities were also distinct. Very little overlap occurred in the pika core bacteria and the most abundant environmental bacteria. The shared OTUs between pikas and environments were present in the environment at relatively low abundance, whereas they were affiliated with diverse bacterial taxa. These results suggested that the pika gut may mainly select for low-abundance but diverse environmental bacteria in a host species-specific manner.

  3. Replicated landscape genetic and network analyses reveal wide variation in functional connectivity for American pikas.

    PubMed

    Castillo, Jessica A; Epps, Clinton W; Jeffress, Mackenzie R; Ray, Chris; Rodhouse, Thomas J; Schwalm, Donelle

    2016-09-01

    Landscape connectivity is essential for maintaining viable populations, particularly for species restricted to fragmented habitats or naturally arrayed in metapopulations and facing rapid climate change. The importance of assessing both structural connectivity (physical distribution of favorable habitat patches) and functional connectivity (how species move among habitat patches) for managing such species is well understood. However, the degree to which functional connectivity for a species varies among landscapes, and the resulting implications for conservation, have rarely been assessed. We used a landscape genetics approach to evaluate resistance to gene flow and, thus, to determine how landscape and climate-related variables influence gene flow for American pikas (Ochotona princeps) in eight federally managed sites in the western United States. We used empirically derived, individual-based landscape resistance models in conjunction with predictive occupancy models to generate patch-based network models describing functional landscape connectivity. Metareplication across landscapes enabled identification of limiting factors for dispersal that would not otherwise have been apparent. Despite the cool microclimates characteristic of pika habitat, south-facing aspects consistently represented higher resistance to movement, supporting the previous hypothesis that exposure to relatively high temperatures may limit dispersal in American pikas. We found that other barriers to dispersal included areas with a high degree of topographic relief, such as cliffs and ravines, as well as streams and distances greater than 1-4 km depending on the site. Using the empirically derived network models of habitat patch connectivity, we identified habitat patches that were likely disproportionately important for maintaining functional connectivity, areas in which habitat appeared fragmented, and locations that could be targeted for management actions to improve functional connectivity

  4. Morphine metabolism in the naturally morphine-tolerant afghan pika: a preliminary study.

    PubMed

    Coimbra-Farges, R; Puget, A; Monsarrat, B; Moisand, C; Meunier, J C

    1990-01-01

    The afghan pika (Ochotona rufescens), a lagomorph which is naturally tolerant to the analgesic action of morphine, metabolizes morphine into morphine 3-glucuronide apparently faster than does the rabbit, another lagomorph which is however normally responsive to morphine. In the two species, following morphine administration, another unidentified component appears very soon (5 min) in pika blood plasma and much later (60 min) in rabbit blood plasma. This unknown component which appears not to be morphine derived might be involved in the natural resistance of the Afghan pika to morphine.

  5. [Impacts of Ochotona pallasi disturbance on alpine grassland community characteristics].

    PubMed

    Zhao, Guo-qin; Li, Guang-yong; Ma, Wen-hu; Zhao, Dian-zhi; Li, Xiao-yan

    2013-08-01

    Plateau pika is the main fossorial mammal in the alpine grassland in Qinghai Lake Watershed of Northwest China. Based on the field investigation data from 18 alpine grassland quadrats in the Watershed, and by using redundancy analysis (RDA) and the surface fitting offered by 'R-Vegan' , the disturbance intensity of plateau pika (Ochotona pallasi) was classified as four levels. In order to explore the impacts of plateau pika disturbance on the alpine grassland ecosystem and its grazing quality, the community characteristics under different disturbance intensities by plateau pika were analyzed, and a conceptual model about the alpine grassland community succession was proposed. The results showed that with the increase of the disturbance intensity, the dominant species changed from Juncus roemerianus to Poa pratensis and Laux maritima. When the disturbance was small, the community had high quantitative values of coverage, aboveground biomass, biodiversity, and species richness, but the proportion of weeds was also high. When the disturbance was large, the quantitative values were the lowest, while the proportion of weeds was the highest. When the disturbance was moderate, the community had relatively high quantitative values, and the proportion of grasses and sedges was the highest. It was concluded that the community' s characteristic values under low plateau pika disturbance intensity were high but the grazing quality was low, while high disturbance intensity resulted in the grassland degradation. Therefore, the disturbance intensity in the threshold could maintain the stability of alpine grassland ecosystem and improve its grazing quality.

  6. Host species shapes the co-occurrence patterns rather than diversity of stomach bacterial communities in pikas.

    PubMed

    Li, Huan; Li, Tongtong; Tu, Bo; Kou, Yongping; Li, Xiangzhen

    2017-07-01

    The mammalian stomach acts as an important barrier against ingested pathogens into the entire gastrointestinal tract, thereby playing a key role in host health. However, little is known regarding to the stomach microbial compositions in wild mammals and the factors that may influence the community compositions. Using high-throughput sequencing of the 16S rRNA gene, we characterized the stomach bacterial community compositions, diversity, and interactions in two common pika (Ochotona sp.) species in China, including Plateau pikas (Ochotona curzoniae) and Daurian pikas (Ochotona daurica) living in the Qinghai-Tibet Plateau and the Inner Mongolia Grassland, respectively. The bacterial communities can be divided into two distinct phylogenetic clusters. The most dominant bacteria in cluster I were unclassified bacteria. Cluster II was more diverse, predominantly consisting of Bacteroidetes, followed by unclassified bacteria, Firmicutes and Proteobacteria. Three dominant genera (Prevotella, Oscillospira, and Ruminococcus) in pika stomachs were significantly enriched in cluster II. In addition, seasons, host species, and sampling sites as well as body weight and sex had no significant impacts on the composition and diversity of pika stomach communities. Interestingly, Plateau pikas harbored a more complex bacterial network than Daurian pikas, and these two pika species showed different co-occurrence patterns. These results suggested that the pika stomach harbors a diverse but relatively stable and unique bacterial community, which is independent on host (host species, body weight, and sex) and measured environmental factors (sampling sites and seasons). Interestingly, host species shapes the microbial interactions rather than diversity of stomach bacterial communities in pikas, reflecting specific niche adaptation of stomach bacterial communities through species interactions.

  7. The mating system and gene dynamics of plateau pikas.

    PubMed

    Dobson; Smith; Xue Gao W

    2000-10-05

    Evolutionary theory suggests that mating systems should have substantial effects on gene dynamics of local populations. In polygynous species, local 'breeding groups' may produce significant genetic structure, due to genetic differences among groups, and rate of loss of genetic variation from such populations may be considerably slowed. We examined possible influences of the variable mating system and family group structure on genetic properties of a population of plateau pikas (Ochotona curzoniae). Pika gene dynamics were examined via F-statistics and effective population sizes (N(e)), calculated from genetic correlations within and among individuals and families. Genetic correlations were estimated from mating patterns, population demography, and dispersal patterns. Substantial genetic structure within the population was indicated by a strongly positive F(LS). Genetic influence of natal dispersal out of pika families was indicated by a strongly negative inbreeding statistic (F(IL)=-0.34). Effective size of the population was not greatly different from the census population, whereas a traditional estimate of effective size of the population was much lower, indicating that the family structure of the pikas results in a slowed loss of genetic variation over time. Thus, even though mating patterns of plateau pikas were variable, family structure had a strong influence on pika gene dynamics.

  8. Behavioral mechanisms of male sterilization on plateau pika in the Qinghai-Tibet plateau.

    PubMed

    Liu, Ming; Qu, Jiapeng; Wang, Zengli; Wang, Yan-Ling; Zhang, Yanming; Zhang, Zhibin

    2012-03-01

    Fertility control is an alternative non-lethal method in the management of rodents. Previous modeling suggests that the efficacy of male sterilization depends on mating systems of animals, but behavioral mechanisms of male sterilization have not been investigated. Here we investigated the behavioral mechanism of the sterilant quinestrol in reducing the fertility of plateau pika (Ochotona curzoniae) inhabiting the Qinghai-Tibet plateau. Male pikas treated with quinestrol showed reduced aggression compared to control males, but they showed significantly higher levels of territorial behavior such as long-calls and long-chases. Levels of long-call and long-chase were negatively correlated with the number of newborn pikas in the family. Single-baiting of quinestrol effectively sterilized male pikas and reduced the pregnancy rate of female pikas; this was likely achieved by increased territorial behavior of sterilized pikas which resulted in unsuccessful invasions by fertile adult male pikas. Our study reveals a novel behavioral mechanism, increased territoriality in sterilized males, in the fertility control of plateau pikas. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Functional Evolution of Leptin of Ochotona curzoniae in Adaptive Thermogenesis Driven by Cold Environmental Stress

    PubMed Central

    Yang, Jie; Bromage, Timothy G.; Zhao, Qian; Xu, Bao Hong; Gao, Wei Li; Tian, Hui Fang; Tang, Hui Jun; Liu, Dian Wu; Zhao, Xin Quan

    2011-01-01

    Background Environmental stress can accelerate the directional selection and evolutionary rate of specific stress-response proteins to bring about new or altered functions, enhancing an organism's fitness to challenging environments. Plateau pika (Ochotona curzoniae), an endemic and keystone species on Qinghai-Tibetan Plateau, is a high hypoxia and low temperature tolerant mammal with high resting metabolic rate and non-shivering thermogenesis to cope in this harsh plateau environment. Leptin is a key hormone related to how these animals regulate energy homeostasis. Previous molecular evolutionary analysis helped to generate the hypothesis that adaptive evolution of plateau pika leptin may be driven by cold stress. Methodology/Principal Findings To test the hypothesis, recombinant pika leptin was first purified. The thermogenic characteristics of C57BL/6J mice injected with pika leptin under warm (23±1°C) and cold (5±1°C) acclimation is investigated. Expression levels of genes regulating adaptive thermogenesis in brown adipose tissue and the hypothalamus are compared between pika leptin and human leptin treatment, suggesting that pika leptin has adaptively and functionally evolved. Our results show that pika leptin regulates energy homeostasis via reduced food intake and increased energy expenditure under both warm and cold conditions. Compared with human leptin, pika leptin demonstrates a superior induced capacity for adaptive thermogenesis, which is reflected in a more enhanced β-oxidation, mitochondrial biogenesis and heat production. Moreover, leptin treatment combined with cold stimulation has a significant synergistic effect on adaptive thermogenesis, more so than is observed with a single cold exposure or single leptin treatment. Conclusions/Significance These findings support the hypothesis that cold stress has driven the functional evolution of plateau pika leptin as an ecological adaptation to the Qinghai-Tibetan Plateau. PMID:21698227

  10. Functional evolution of leptin of Ochotona curzoniae in adaptive thermogenesis driven by cold environmental stress.

    PubMed

    Yang, Jie; Bromage, Timothy G; Zhao, Qian; Xu, Bao Hong; Gao, Wei Li; Tian, Hui Fang; Tang, Hui Jun; Liu, Dian Wu; Zhao, Xin Quan

    2011-01-01

    Environmental stress can accelerate the directional selection and evolutionary rate of specific stress-response proteins to bring about new or altered functions, enhancing an organism's fitness to challenging environments. Plateau pika (Ochotona curzoniae), an endemic and keystone species on Qinghai-Tibetan Plateau, is a high hypoxia and low temperature tolerant mammal with high resting metabolic rate and non-shivering thermogenesis to cope in this harsh plateau environment. Leptin is a key hormone related to how these animals regulate energy homeostasis. Previous molecular evolutionary analysis helped to generate the hypothesis that adaptive evolution of plateau pika leptin may be driven by cold stress. To test the hypothesis, recombinant pika leptin was first purified. The thermogenic characteristics of C57BL/6J mice injected with pika leptin under warm (23±1°C) and cold (5±1°C) acclimation is investigated. Expression levels of genes regulating adaptive thermogenesis in brown adipose tissue and the hypothalamus are compared between pika leptin and human leptin treatment, suggesting that pika leptin has adaptively and functionally evolved. Our results show that pika leptin regulates energy homeostasis via reduced food intake and increased energy expenditure under both warm and cold conditions. Compared with human leptin, pika leptin demonstrates a superior induced capacity for adaptive thermogenesis, which is reflected in a more enhanced β-oxidation, mitochondrial biogenesis and heat production. Moreover, leptin treatment combined with cold stimulation has a significant synergistic effect on adaptive thermogenesis, more so than is observed with a single cold exposure or single leptin treatment. These findings support the hypothesis that cold stress has driven the functional evolution of plateau pika leptin as an ecological adaptation to the Qinghai-Tibetan Plateau.

  11. Testis-specific lactate dehydrogenase is expressed in somatic tissues of plateau pikas.

    PubMed

    Wang, Duowei; Wei, Lian; Wei, Dengbang; Rao, Xinfeng; Qi, Xinzhang; Wang, Xiaojun; Ma, Benyuan

    2013-01-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the interconversion of pyruvate with lactate. In mammals the, Ldh-c gene was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), belonging to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living at 3000-5000 m above sea levelon the Qinghai-Tibet Plateau. We found that the expression pattern of six LDH isoenzymes in the somatic tissues of female and male plateau pikas to be the same as those in testis and sperm, suggesting that LDH-C4 was expressed in somatic tissues of plateau pika. Here we report the detection of LDHC in the somatic tissues of plateau pika using RT-PCR, Western blotting and immunohistochemistry. Our results indicate that Ldh-c mRNA is transcribed in the heart, liver, lung, kidney, brain, skeletal muscle and testis. In somatic tissues LDHC was translated in the cytoplasm, while in testis it was expressed in both cytoplasm and mitochondria. The third band from cathode to anode in LDH isoenzymes was identified as LDH-C4. The finding that Ldh-c is expressed in both somatic tissues and testis of plateau pika provides important implications for more in-depth research into the Ldh-c function in mammals.

  12. Mitochondrial genome analysis of Ochotona curzoniae and implication of cytochrome c oxidase in hypoxic adaptation.

    PubMed

    Luo, Yongjun; Gao, Wenxiang; Gao, Yuqi; Tang, Sha; Huang, Qingyuan; Tan, Xiaoling; Chen, Jian; Huang, Taosheng

    2008-12-01

    Pikas originated in Asia and are small lagomorphs native to cold climates. The plateau pika, Ochotona curzoniae is a keystone species on the Qinghai-Tibet Plateau and an ideal animal model for hypoxic adaptation studies. Altered mitochondrial function, especially cytochrome c oxidase activity, is an important factor in modulation of energy generation and expenditure during cold and hypoxia adaptation. In this study, we determined the complete nucleotide sequence of the O. curzoniae mitochondrial genome. The plateau pika mitochondrial DNA is 17,131bp long and encodes the complete set of 37 proteins typical for vertebrates. Phylogenetic analysis based on concatenated heavy-strand encoded protein-coding genes revealed that pikas are closer to rabbit and hare than to rat. This suggests that rabbit or hare would be a good control animal for pikas in cold and hypoxia adaptation studies. Fifteen novel mitochondrial DNA-encoded amino acid changes were identified in the pikas, including three in the subunits of cytochrome c oxidase. These amino acid substitutions potentially function in modulation of mitochondrial complexes and electron transport efficiency during cold and hypoxia adaptation.

  13. Echinococcus shiquicus n. sp., a taeniid cestode from Tibetan fox and plateau pika in China.

    PubMed

    Xiao, Ning; Qiu, Jiamin; Nakao, Minoru; Li, Tiaoying; Yang, Wen; Chen, Xingwang; Schantz, Peter M; Craig, Philip S; Ito, Akira

    2005-05-01

    The taeniid cestode Echinococcus shiquicus n. sp. was found from the Tibetan fox Vulpes ferrilata and the plateau pika Ochotona curzoniae in the Qinghai-Tibet plateau region of China. In the adult stage, E. shiquicus from the foxes is morphologically similar to Echinococcus multilocularis. However, the new species is differentiated by its smaller rostellar hooks, fewer segments, distinct position of genital pore in the mature segment and fewer eggs in the gravid segment. Hydatid cysts of E. shiquicus found in the livers from the pikas were essentially unilocular but an oligovesicular cyst was also found. The data of mitochondrial and nuclear DNA sequences proved E. shiquicus to be a valid taxon.

  14. Collared Pikas as a Model Species for Studying the Biological Impacts of Climate Change in Alpine Ecosystems

    NASA Astrophysics Data System (ADS)

    O'Donovan, K. S.; Hik, D.

    2007-12-01

    Climate models suggest that global temperatures could rise between 1.4° C and 5.8° C over the next 100 years, and that these effects will be most extreme in northern mountain regions. Pikas (Ochotona, Lagomorpha) are widespread small mammals in the alpine environments of Asia and North America. They are cold adapted and consequently sensitive to warming global temperatures. Considerable research has shown a poleward migration of many species as a result of rising temperatures, but high alpine dwelling species, like the pika, may already be trapped at the top of mountains. Little is known about the threshold values of environmental conditions under which pikas either persist or disappear. Collared pikas (Ochotona collaris) inhabit alpine meadows in the Kluane region of the southwest Yukon. Sites located along an environmental gradient from nunataks in the St Elias Icefields to the Ruby Range Mountains have experienced different climatic and glacial histories. Using baseline data from the long-term study in the Ruby Ranges, we report on differences in the ecological and climatic conditions of sites along this gradient and how this translates into differences in the behavioural and population ecology of the pikas living there. By looking at these differences we can infer the potential impacts of a warming climate, and the subsequent ecological changes on collared pika populations in order to clarify the causes of local extinction and allow us to develop models for predicting ecological responses as conditions change under future climate regimes.

  15. Effect of Hypoxia on Ldh-c Expression in Somatic Cells of Plateau Pika.

    PubMed

    Wei, Dengbang; Wei, Linna; Li, Xiao; Wang, Yang; Wei, Lian

    2016-08-01

    Sperm specific lactate dehydrogenases (LDH-C₄) is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, Ldh-c was originally thought to be expressed only in testes and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia-tolerant mammal living 3000-5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testes and sperm, but also in the somatic tissues of plateau pika. To reveal the effect of hypoxia on pika Ldh-c expression, we investigated the mRNA and protein level of Ldh-c as well as the biochemical index of anaerobic glycolysis in pika somatic tissues at the altitudes of 2200 m, 3200 m and 3900 m. Our results showed that mRNA and protein expression levels of Ldh-c in the tissues of pika's heart, liver, brain and skeletal muscle were increased significantly from 2200 m to 3200 m, but had no difference from 3200 m to 3900 m; the activities of LDH and the contents of lactate showed no difference from 2200 m to 3200 m, but were increased significantly from 3200 m to 3900 m. Hypoxia up-regulated and maintained the expression levels of Ldh-c in the pika somatic cells. Under the hypoxia condition, plateau pikas increased anaerobic glycolysis in somatic cells by LDH-C₄, and that may have reduced their dependence on oxygen and enhanced their adaptation to the hypoxic environment.

  16. Natural Selection and Adaptive Evolution of Leptin in the Ochotona Family Driven by the Cold Environmental Stress

    PubMed Central

    Yang, Jie; Wang, Zhen Long; Zhao, Xin Quan; Wang, De Peng; Qi, De Lin; Xu, Bao Hong; Ren, Yong Hong; Tian, Hui Fang

    2008-01-01

    Background Environmental stress can accelerate the evolutionary rate of specific stress-response proteins and create new functions specialized for different environments, enhancing an organism's fitness to stressful environments. Pikas (order Lagomorpha), endemic, non-hibernating mammals in the modern Holarctic Region, live in cold regions at either high altitudes or high latitudes and have a maximum distribution of species diversification confined to the Qinghai-Tibet Plateau. Variations in energy metabolism are remarkable for them living in cold environments. Leptin, an adipocyte-derived hormone, plays important roles in energy homeostasis. Methodology/Principal Findings To examine the extent of leptin variations within the Ochotona family, we cloned the entire coding sequence of pika leptin from 6 species in two regions (Qinghai-Tibet Plateau and Inner Mongolia steppe in China) and the leptin sequences of plateau pikas (O. curzonia) from different altitudes on Qinghai-Tibet Plateau. We carried out both DNA and amino acid sequence analyses in molecular evolution and compared modeled spatial structures. Our results show that positive selection (PS) acts on pika leptin, while nine PS sites located within the functionally significant segment 85-119 of leptin and one unique motif appeared only in pika lineages-the ATP synthase α and β subunit signature site. To reveal the environmental factors affecting sequence evolution of pika leptin, relative rate test was performed in pikas from different altitudes. Stepwise multiple regression shows that temperature is significantly and negatively correlated with the rates of non-synonymous substitution (Ka) and amino acid substitution (Aa), whereas altitude does not significantly affect synonymous substitution (Ks), Ka and Aa. Conclusions/Significance Our findings support the viewpoint that adaptive evolution may occur in pika leptin, which may play important roles in pikas' ecological adaptation to extreme environmental

  17. The pika and the watershed: The impact of small mammal poisoning on the ecohydrology of the Qinghai-Tibetan Plateau.

    PubMed

    Wilson, Maxwell C; Smith, Andrew T

    2015-02-01

    With approximately 20 % of the world's population living in its downstream watersheds, the Qinghai-Tibetan Plateau (QTP) is considered "Asia's Water Tower." However, grasslands of the QTP, where most of Asia's great rivers originate, are becoming increasingly degraded, which leads to elevated population densities of a native small mammal, the plateau pika (Ochotona curzoniae). As a result pikas have been characterized as a pest leading to wide-spread poisoning campaigns in an attempt to restore grassland quality. A contrary view is that pikas are a keystone species for biodiversity and that their burrowing activity provides a critical ecosystem service by increasing the infiltration rate of water, hence reducing overland flow. We demonstrate that poisoning plateau pikas significantly reduces infiltration rate of water across the QTP creating the potential for watershed-level impacts. Our results demonstrate the importance of burrowing mammals as ecosystem engineers, particularly with regard to their influence on hydrological functioning.

  18. The burying and grazing effects of plateau pika on alpine grassland are small: a pilot study in a semiarid basin on the Qinghai-Tibet Plateau

    NASA Astrophysics Data System (ADS)

    Yi, Shuhua; Chen, Jianjun; Qin, Yu; Xu, Gaowei

    2016-11-01

    There is considerable controversy about the effects of plateau pika (Ochotona curzoniae, hereafter pika) on alpine grassland on the Qinghai-Tibet Plateau (QTP). On the one hand, pika is considered a keystone species. On the other hand, it is being poisoned. Although significant efforts have been made to study the effects of pika at a quadrat scale ( ˜ m2), our knowledge about its distribution and effects at a larger scale is very limited. In this study, we investigated the direct effects, i.e., burying and grazing, of pika by upscaling field sampling at a quadrat scale to a plot scale ( ˜ 1000 m2) by aerial photographing. Altogether 168 plots were set on four different types of alpine grassland in a semiarid basin on the QTP. Results showed that (1) the effects of pika pile burying on the reduction of vegetation cover, biomass, soil carbon, and nitrogen were less than 10 %, which was much smaller than the effects of bald patches; and (2) pika consumed 8-21 % of annual net primary production of grassland. We concluded that the direct burying and grazing effects of pika on alpine grassland were minor in this region. The quadcopter is an efficient and economic tool for long-term repeated monitoring over large regions for further understanding the role of pika.

  19. Spatially explicit models of dynamic histories: examination of the genetic consequences of Pleistocene glaciation and recent climate change on the American Pika.

    PubMed

    Brown, Jason L; Knowles, L Lacey

    2012-08-01

    A central goal of phylogeography is to identify and characterize the processes underlying divergence. One of the biggest impediments currently faced is how to capture the spatiotemporal dynamic under which a species evolved. Here, we described an approach that couples species distribution models (SDMs), demographic and genetic models in a spatiotemporally explicit manner. Analyses of American Pika (Ochotona princeps) from the sky islands of the central Rocky Mountains of North America are used to provide insights into key questions about integrative approaches in landscape genetics, population genetics and phylogeography. This includes (i) general issues surrounding the conversion of time-specific SDMs into simple continuous, dynamic landscapes from past to current, (ii) the utility of SDMs to inform demographic models with deme-specific carrying capacities and migration potentials as well as (iii) the contribution of the temporal dynamic of colonization history in shaping genetic patterns of contemporary populations. Our results support that the inclusion of a spatiotemporal dynamic is an important factor when studying the impact of distributional shifts on patterns of genetic data. Our results also demonstrate the utility of SDMs to generate species-specific predictions about patterns of genetic variation that account for varying degrees of habitat specialization and life history characteristics of taxa. Nevertheless, the results highlight some key issues when converting SDMs for use in demographic models. Because the transformations have direct effects on the genetic consequence of population expansion by prescribing how habitat heterogeneity and spatiotemporal variation is related to the species-specific demographic model, it is important to consider alternative transformations when studying the genetic consequences of distributional shifts. © 2012 Blackwell Publishing Ltd.

  20. After the frass: foraging pikas select patches previously grazed by caterpillars

    PubMed Central

    Barrio, Isabel C.; Hik, David S.; Peck, Kristen; Bueno, C. Guillermo

    2013-01-01

    Interactions among herbivores can shape the structure of their communities and drive their dynamics. However, detecting herbivore interactions can be challenging when they are deferred in space or time. Moreover, interactions among distantly related groups of herbivores, such as vertebrates and invertebrates, are poorly understood. We investigated the effect of invertebrate herbivory on the subsequent foraging choices of a small alpine-dwelling vertebrate, the collared pika (Ochotona collaris). We carried out a field experiment within pika territories, by presenting them with a choice of foraging sites following manipulation of invertebrate (caterpillar) herbivory. Pikas actively selected areas with increased, recent invertebrate herbivory. While the underlying mechanisms behind this interaction remain unknown, our results demonstrate a positive effect of invertebrate herbivores on subsequent vertebrate foraging preferences for the first time. Even among distantly related taxa, such interactions where one herbivore is cueing on the foraging of another, could drive the creation of herbivory hotspots, with cascading consequences for ecosystem processes. PMID:23616644

  1. After the frass: foraging pikas select patches previously grazed by caterpillars.

    PubMed

    Barrio, Isabel C; Hik, David S; Peck, Kristen; Bueno, C Guillermo

    2013-06-23

    Interactions among herbivores can shape the structure of their communities and drive their dynamics. However, detecting herbivore interactions can be challenging when they are deferred in space or time. Moreover, interactions among distantly related groups of herbivores, such as vertebrates and invertebrates, are poorly understood. We investigated the effect of invertebrate herbivory on the subsequent foraging choices of a small alpine-dwelling vertebrate, the collared pika (Ochotona collaris). We carried out a field experiment within pika territories, by presenting them with a choice of foraging sites following manipulation of invertebrate (caterpillar) herbivory. Pikas actively selected areas with increased, recent invertebrate herbivory. While the underlying mechanisms behind this interaction remain unknown, our results demonstrate a positive effect of invertebrate herbivores on subsequent vertebrate foraging preferences for the first time. Even among distantly related taxa, such interactions where one herbivore is cueing on the foraging of another, could drive the creation of herbivory hotspots, with cascading consequences for ecosystem processes.

  2. Effect of Hypoxia on Ldh-c Expression in Somatic Cells of Plateau Pika

    PubMed Central

    Wei, Dengbang; Wei, Linna; Li, Xiao; Wang, Yang; Wei, Lian

    2016-01-01

    Sperm specific lactate dehydrogenases (LDH-C4) is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, Ldh-c was originally thought to be expressed only in testes and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia-tolerant mammal living 3000–5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testes and sperm, but also in the somatic tissues of plateau pika. To reveal the effect of hypoxia on pika Ldh-c expression, we investigated the mRNA and protein level of Ldh-c as well as the biochemical index of anaerobic glycolysis in pika somatic tissues at the altitudes of 2200 m, 3200 m and 3900 m. Our results showed that mRNA and protein expression levels of Ldh-c in the tissues of pika’s heart, liver, brain and skeletal muscle were increased significantly from 2200 m to 3200 m, but had no difference from 3200 m to 3900 m; the activities of LDH and the contents of lactate showed no difference from 2200 m to 3200 m, but were increased significantly from 3200 m to 3900 m. Hypoxia up-regulated and maintained the expression levels of Ldh-c in the pika somatic cells. Under the hypoxia condition, plateau pikas increased anaerobic glycolysis in somatic cells by LDH-C4, and that may have reduced their dependence on oxygen and enhanced their adaptation to the hypoxic environment. PMID:27490559

  3. Effects of hypoxia on contents of essential elements in pika and rat heart.

    PubMed

    Suo, Yourui; Wang, Hanqing; Zhang, Baochen

    2005-02-01

    The effects of hypoxia on the levels of essential macroelements and trace elements (K, Na, Ca, Mg, Cu, Zn, Fe, and Mn) in the heart muscles of Wistar rats and plateau pikas (Ochotona curzoniae) were studied by atomic absorption spectrometry. Unlike the rat, the plateau pika is tolerant to hypoxia. The levels of K, Na, and the trace element Mn were not significantly changed in rat or pika hearts after exposure to hypoxia for 1, 10, or 25 d at simulated altitudes of 5000 and 7000 m. Other minerals (Ca, Mg, Cu, Zn, and Fe) were significantly affected by hypoxia and the levels followed different time-courses under different hypoxic regimes in these two animals. There were marked differences between the rat and pika in myocardial accumulation of essential elements such as Ca, which was increased to high levels in the rat but not affected in the pika. The results suggest that hypoxia affects animal physiological mechanisms by regulating the levels of essential elements.

  4. Metabolic Alterations of Qinghai-Tibet Plateau Pikas in Adaptation to High Altitude.

    PubMed

    Cao, Xue-Feng; Bai, Zhen-Zhong; Ma, Lan; Ma, Shuang; Ge, Ri-Li

    2017-09-01

    Cao, Xue-Feng, Zhen-Zhong Bai, Lan Ma, Shuang Ma, and Ri-Li Ge. Metabolic alterations of Qinghai-Tibet plateau pikas in adaptation to high altitude. High Alt Med Biol. 18:219-225, 2017.-To determine specific metabolic alterations in the myocardium of plateau pikas (Ochotona curzoniae) and potential metabolic biomarkers involved in their adaptation to the high-altitude environment of the Qinghai-Tibet Plateau. Ten pikas were captured by traps in the Kekexili Reserve (4630 m a.s.l; n = 5) and at the foot of the Laji Mountain (2600 m a.s.l; n = 5) on the Qinghai-Tibet Plateau, Qinghai Province, China. Metabolite levels were determined by gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) metabolomics, and multivariate statistical analysis was performed. Several metabolites involved in carbohydrate, fat, energy, and redox homeostasis pathways were significantly altered in pikas living at 4630 m. In addition, those pikas showed increased levels of lactic acid, sarcosine, 4-hydroxybutyrate, methionine, tartaric acid, ribose, tyrosine, pentadecanoic acid, 2-monoolein, 3,5-dihydroxyphenylglycine, trehalose-6-phosphate, succinic acid, myoinositol, fumaric acid, taurine, 2-hydroxybutanoic acid, gluconic acid, citrulline, and glutathione, but decreased levels of oleic acid and 2'-deoxyadenosine 5'-monophosphate. Metabolic activity is significantly altered in the myocardium of pikas in the high-altitude areas of the Qinghai-Tibet Plateau. This study provides important insights into metabolic biomarkers related to the adaptation of pikas to high-altitude hypoxia.

  5. A random forest approach for predicting the presence of Echinococcus multilocularis intermediate host Ochotona spp. presence in relation to landscape characteristics in western China

    PubMed Central

    Marston, Christopher G.; Danson, F. Mark; Armitage, Richard P.; Giraudoux, Patrick; Pleydell, David R.J.; Wang, Qian; Qui, Jiamin; Craig, Philip S.

    2014-01-01

    Understanding distribution patterns of hosts implicated in the transmission of zoonotic disease remains a key goal of parasitology. Here, random forests are employed to model spatial patterns of the presence of the plateau pika (Ochotona spp.) small mammal intermediate host for the parasitic tapeworm Echinococcus multilocularis which is responsible for a significant burden of human zoonoses in western China. Landsat ETM+ satellite imagery and digital elevation model data were utilized to generate quantified measures of environmental characteristics across a study area in Sichuan Province, China. Land cover maps were generated identifying the distribution of specific land cover types, with landscape metrics employed to describe the spatial organisation of land cover patches. Random forests were used to model spatial patterns of Ochotona spp. presence, enabling the relative importance of the environmental characteristics in relation to Ochotona spp. presence to be ranked. An index of habitat aggregation was identified as the most important variable in influencing Ochotona spp. presence, with area of degraded grassland the most important land cover class variable. 71% of the variance in Ochotona spp. presence was explained, with a 90.98% accuracy rate as determined by ‘out-of-bag’ error assessment. Identification of the environmental characteristics influencing Ochotona spp. presence enables us to better understand distribution patterns of hosts implicated in the transmission of Em. The predictive mapping of this Em host enables the identification of human populations at increased risk of infection, enabling preventative strategies to be adopted. PMID:25386042

  6. The life cycle of Ohbayashinema erbaevae (Nematoda, Heligmosomoidea, Heligmosomidae) in Ochotona rufescens rufescens (Ochotonidae).

    PubMed

    Audebert, F; Cassone, J; Baccam, D; Kerboeuf, D; Durette-Desset, M C

    2001-12-01

    The morphogenesis and the chronology of the life cycle of Ohbayashinema erbaevoe Durette-Desset et al, 2000, a parasite of Ochotona daurica from Buriatia were studied in detail in an experimental host, Ochotona rufescens rufescens. Worm-free pikas were each infected per os with O. erbaevae larvae and were killed at one day post infection (DPI 1) and every 12 hours from 1.5 to 8 days post infection. By DPI 1, all the larvae were exsheathed and in the small intestine. The third moult occurred in 2.5-3.0 days. The last moult occurred in 4.0-4.5 days. The prepatent period was eight days and the patent period lasted between two and 12 weeks. The distribution of O. erbaevae along the small intestine of the pikas was assessed. For each experiment, a morphological description of the different stages of the life cycle was provided. The morphogenesis and the chronology of the life cycle of O. erbaevae appear to be identical with those of two other genera of the family of the Heligmosomidae, Heligmosomum Railliet & Henry, 1909 and Heligmosomoides Hall, 1916. They confirm that the three genera belong to the same family. The presence of an abortive posterior genital branch in the female of O. erbaevae, which represents the posterior part of the genital primordium of the didelphic females, supports the systematic position of the genus Ohbayashinema between the didelphic genus Citellinema Hall, 1916 and the monodelphic genera Heligmosomum and Heligmosomoides.

  7. [Length and weight of gastrointestinal tracts of pikas, suncus, millardias, mice and rats].

    PubMed

    Yamanaka, M; Matsuzaki, T; Saito, M

    1983-01-01

    The length and weight of gastrointestinal tracts including contents of ten week old male pikas (Ochotona rufescens rufescens) and suncus (Suncus murinus) were measured and they were investigated and compared with those of millardias, ICR-mice and Wistar-rats. The length from the duodenum to the anus of pikas was much longer and the weight from the stomach to the anus was about 16g per 100g of body weight. The weight of cecum was about 7g per body weight and they were heavier than those of other species. The length from the duodenum to the anus of the suncus was short but the weight of the small intestine plus colon and rectum per body weight did not differ from that of other species. The suncus has no cecum but the weight from the stomach to the anus was almost the same as that of rats.

  8. Genetics, morphology and ecology reveal a cryptic pika lineage in the Sikkim Himalaya.

    PubMed

    Dahal, Nishma; Lissovsky, Andrey A; Lin, Zhenzhen; Solari, Katherine; Hadly, Elizabeth A; Zhan, Xiangjiang; Ramakrishnan, Uma

    2017-01-01

    Asian pika species are morphologically ∼similar and have overlapping ranges. This leads to uncertainty and species misidentification in the field. Phylogenetic analyses of such misidentified samples leads to taxonomic ambiguity. The ecology of many pika species remains understudied, particularly in the Himalaya, where sympatric species could be separated by elevation and/or substrate. We sampled, measured, and acquired genetic data from pikas in the Sikkim Himalaya. Our analyses revealed a cryptic lineage, Ochotona sikimaria, previously reported as a subspecies of O. thibetana. The results support the elevation of this lineage to the species level, as it is genetically divergent from O. thibetana, as well as sister species, O. cansus (endemic to central China) and O. curzoniae (endemic to the Tibetan plateau). The Sikkim lineage diverged from its sister species' about 1.7-0.8myrago, coincident with uplift events in the Himalaya. Our results add to the recent spate of cryptic diversity identified from the eastern Himalaya and highlight the need for further study within the Ochotonidae. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Postnatal ontogenetic size and shape changes in the craniums of plateau pika and woolly hare (Mammalia: Lagomorpha).

    PubMed

    Zhang, Zhi-Gui; Ge, De-Yan

    2014-07-01

    In the present study, postnatal ontogenetic size and shape changes in the cranium of two lagomorph species, the plateau pika (Ochotona curzoniae) and woolly hare (Lepus oiostolus), were investigated by geometric morphometrics. The ontogenetic size and shape changes of their cranium exhibited different growth patterns in response to similar environmental pressures on the Qinghai-Tibetan Plateau. The overall size change in the cranium of the plateau pika was slower than that of the woolly hare. The percentage of ontogenetic shape variance explained by size in the woolly hare was greater than that in the plateau pika. The overall shape of the cranium was narrowed in both species, and morphological components in relation to neural maturity showed negative allometry, while those responsible for muscular development showed isometric or positive allometry. The most remarkable shape variations in the plateau pika were associated with food acquisition (temporalis development), though other remarkable shape variations in the incisive and palatal foramen in the ventral view were also observed. The most important shape change in the woolly hare was demonstrated by the elongation of the nasal bones, expansion of the supra-orbital process and shape variation of the neurocranium.

  10. Postnatal ontogenetic size and shape changes in the craniums of plateau pika and woolly hare (Mammalia: Lagomorpha)

    PubMed Central

    Zhi-Gui, ZHANG; De-Yan, GE

    2014-01-01

    In the present study, postnatal ontogenetic size and shape changes in the cranium of two lagomorph species, the plateau pika (Ochotona curzoniae) and woolly hare (Lepus oiostolus), were investigated by geometric morphometrics. The ontogenetic size and shape changes of their cranium exhibited different growth patterns in response to similar environmental pressures on the Qinghai-Tibetan Plateau. The overall size change in the cranium of the plateau pika was slower than that of the woolly hare. The percentage of ontogenetic shape variance explained by size in the woolly hare was greater than that in the plateau pika. The overall shape of the cranium was narrowed in both species, and morphological components in relation to neural maturity showed negative allometry, while those responsible for muscular development showed isometric or positive allometry. The most remarkable shape variations in the plateau pika were associated with food acquisition (temporalis development), though other remarkable shape variations in the incisive and palatal foramen in the ventral view were also observed. The most important shape change in the woolly hare was demonstrated by the elongation of the nasal bones, expansion of the supra-orbital process and shape variation of the neurocranium. PMID:25017747

  11. Distribution of sialic acid receptors and experimental infections with different subtypes of influenza A viruses in Qinghai-Tibet plateau wild pika.

    PubMed

    Li, Yan; Xiao, Haixia; Huang, Chaobin; Sun, Haigang; Li, Laixing; Su, Jingliang; Ma, Juncai; Liu, Di; Wang, Han; Liu, Wenjun; Gao, George F; Li, Xiangdong; Yan, Jinghua

    2015-04-14

    The plateau pika (Ochotona curzoniae) is a small rabbit-like mammal that lives at high altitudes in the Qinghai-Tibet plateau and is in close contact with birds. Following the outbreak of highly pathogenic avian influenza (HPAI) H5N1 during 2005 in the migratory birds of Qinghai Lake, two clades of H5N1 have been found in pikas. However, the influenza virus receptor distribution in different tissues of this animal and its susceptibility to influenza A viruses have remained unclear. The sialic acid receptor distribution tropism in pika was investigated using fluorescent Sambucus nigra and biotinylated Maackia amurensis I and II. Furthermore, the replication of three influenza A viruses H1N1, H3N2, and H5N1 in this animal was examined by immunohistochemistry and RT-PCR. Morphological and histopathological changes caused by infection were also analyzed with hematoxylin and eosin (H & E) staining. Human influenza virus-recognizing SAα2,6Gal receptors are widely expressed in the lung, kidney, liver, spleen, duodenum, ileum, rectum, and heart, whereas avian influenza virus-recognizing SAα2,3Gal receptors are strongly expressed in the trachea and lung of pika. M1 could be detected in the lungs of pikas infected with H1N1, H3N2, and H5N1 by either immunostaining or RT-PCR, and in the brain of H5N1-infected pikas. Additionally, three subtypes of influenza A viruses were able to infect pika and caused varying degrees of pneumonia with epithelial desquamation and alveolar inflammatory cell infiltration. Slight pathological changes were observed in H1N1-infected lungs. A few small bronchi and terminal bronchioles were infiltrated by lymphocytic cells in H3N2-infected lungs. In contrast, serious lung damage, such as alveolar capillary hyperemia, edema, alveolar collapse, and lymphocytic infiltrations was observed in H5N1-infected group. Furthermore, neural system changes were present in the brains of H5N1-infected pikas. SAα2,6Gal receptors are extensively present in many of

  12. Testis-Specific Lactate Dehydrogenase (LDH-C4) in Skeletal Muscle Enhances a Pika's Sprint-Running Capacity in Hypoxic Environment.

    PubMed

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2015-08-07

    LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000-5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in Qinghai-Tibet plateau

  13. Pika Population Density Is Associated with the Composition and Diversity of Gut Microbiota

    PubMed Central

    Li, Huan; Qu, Jiapeng; Li, Tongtong; Li, Jiabao; Lin, Qiang; Li, Xiangzhen

    2016-01-01

    Host population density is positively associated with the strength of social interactions or the frequency of physical contacts, and thus potentially influences microbial transmission among individuals. However, the relationship between host density and gut microbiota remains unknown. Here, we characterized the gut microbiota of plateau pikas (Ochotona curzoniae) in wild experimental fields with different host population densities. The abundance of some gut microbes significantly correlated with host density, such as Ruminococcaceae, Lachnospiraceae, and Staphylococcaceae. Intriguingly, host density was positively correlated with alpha diversity (Shannon diversity and observed species) of gut microbial communities. The inter-individual gut microbiota within high-density groups were more similar to each other than those of low-density groups. Host density significantly explained the variations in the gut microbiota, even after controlling sex, weight, diet and geographical locations. Based on the PICRUSt metagenome prediction, positive correlations were observed between host density and the relative abundances of 12 gene functions involved in cellular processes, environmental information processing and metabolism. These results indicate the importance of host density as a factor in shaping gut microbial composition and diversity in plateau pikas, and may further help us understand the social transmission of gut microbiota. PMID:27242770

  14. Pika Population Density Is Associated with the Composition and Diversity of Gut Microbiota.

    PubMed

    Li, Huan; Qu, Jiapeng; Li, Tongtong; Li, Jiabao; Lin, Qiang; Li, Xiangzhen

    2016-01-01

    Host population density is positively associated with the strength of social interactions or the frequency of physical contacts, and thus potentially influences microbial transmission among individuals. However, the relationship between host density and gut microbiota remains unknown. Here, we characterized the gut microbiota of plateau pikas (Ochotona curzoniae) in wild experimental fields with different host population densities. The abundance of some gut microbes significantly correlated with host density, such as Ruminococcaceae, Lachnospiraceae, and Staphylococcaceae. Intriguingly, host density was positively correlated with alpha diversity (Shannon diversity and observed species) of gut microbial communities. The inter-individual gut microbiota within high-density groups were more similar to each other than those of low-density groups. Host density significantly explained the variations in the gut microbiota, even after controlling sex, weight, diet and geographical locations. Based on the PICRUSt metagenome prediction, positive correlations were observed between host density and the relative abundances of 12 gene functions involved in cellular processes, environmental information processing and metabolism. These results indicate the importance of host density as a factor in shaping gut microbial composition and diversity in plateau pikas, and may further help us understand the social transmission of gut microbiota.

  15. Diet Diversity Is Associated with Beta but not Alpha Diversity of Pika Gut Microbiota

    PubMed Central

    Li, Huan; Li, Tongtong; Beasley, DeAnna E.; Heděnec, Petr; Xiao, Zhishu; Zhang, Shiheng; Li, Jiabao; Lin, Qiang; Li, Xiangzhen

    2016-01-01

    Wild mammals often consume different food sources as they become geographical available. This change in diet composition is likely to influence the gut microbial community, yet it remains unclear what the relationship looks like—particularly in small herbivores—under natural conditions. We used DNA sequencing approaches to characterize the diet composition and gut microbial community of wild plateau pikas (Ochotona curzoniae) collected from three altitudes. We tested if diet and gut microbiota composition changes across altitudes, and the relationship between diet diversity and gut microbiota diversity. Our results showed that altitude significantly influences the composition of diet and gut microbial communities. Notably, the alpha diversity (Shannon diversity and observed OTUs) of individual diet was not significantly correlated with that of gut microbiota, whereas the beta diversity (Jaccard and Bray-Curtis dissimilarity) of diet was positively correlated with that of gut microbiota. Our study is the first time to highlight the relationship between diet and gut microbiota composition in wild pikas on the Qinghai-Tibet Plateau. It suggests that the species richness within individual gut microbiota does not linearly increase with diet diversity, whereas those individuals that are more similar in diet composition harbor more similar gut microbiota. PMID:27512391

  16. Diet Diversity Is Associated with Beta but not Alpha Diversity of Pika Gut Microbiota.

    PubMed

    Li, Huan; Li, Tongtong; Beasley, DeAnna E; Heděnec, Petr; Xiao, Zhishu; Zhang, Shiheng; Li, Jiabao; Lin, Qiang; Li, Xiangzhen

    2016-01-01

    Wild mammals often consume different food sources as they become geographical available. This change in diet composition is likely to influence the gut microbial community, yet it remains unclear what the relationship looks like-particularly in small herbivores-under natural conditions. We used DNA sequencing approaches to characterize the diet composition and gut microbial community of wild plateau pikas (Ochotona curzoniae) collected from three altitudes. We tested if diet and gut microbiota composition changes across altitudes, and the relationship between diet diversity and gut microbiota diversity. Our results showed that altitude significantly influences the composition of diet and gut microbial communities. Notably, the alpha diversity (Shannon diversity and observed OTUs) of individual diet was not significantly correlated with that of gut microbiota, whereas the beta diversity (Jaccard and Bray-Curtis dissimilarity) of diet was positively correlated with that of gut microbiota. Our study is the first time to highlight the relationship between diet and gut microbiota composition in wild pikas on the Qinghai-Tibet Plateau. It suggests that the species richness within individual gut microbiota does not linearly increase with diet diversity, whereas those individuals that are more similar in diet composition harbor more similar gut microbiota.

  17. Herbivory and Competition of Tibetan Steppe Vegetation in Winter Pasture: Effects of Livestock Exclosure and Plateau Pika Reduction.

    PubMed

    Harris, Richard B; Wenying, Wang; Badinqiuying; Smith, Andrew T; Bedunah, Donald J

    2015-01-01

    Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP). Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae), assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover) with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures, but may not

  18. Herbivory and Competition of Tibetan Steppe Vegetation in Winter Pasture: Effects of Livestock Exclosure and Plateau Pika Reduction

    PubMed Central

    Harris, Richard B.; Wenying, Wang; Badinqiuying; Smith, Andrew T.

    2015-01-01

    Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP). Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae), assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover) with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures, but may not

  19. [Ocular and auditory organs of Ochotona rufescens].

    PubMed

    Yokota, M; Suzuki, H; Hata, T; Sakamoto, K; Takeda, U

    1983-10-01

    Ochotona rufescens is an animal species native to Afghanistan, and is among many new animal species currently being raised for use in experimental research in Japan. In the present paper, we report morphological findings on ocular and auditory character of Ochotona rufescens examined first under normal conditions and then under the influence of various agents, and the results were compared with those on other experimental animals used in this study. On histological examination, the cochlear portion of the labyrinth was found to consist of a coiled canal making two and one half turns from its basal end to the upper turn, and was identical to those of cats and rabbits. Moreover, triple rows of outer sensory hair cells and a single row of inner sensory hair cells were observed. Kanamycin and furosemide (Lasix), a diuretic, were administered 10 min. apart to determine the effects of these drugs on pinna reflex, however, as a result of these administration, none of the Ochotona rufescens tested showed any appreciable depression of this reflex. By funduscopic observation with photographic records, principal retinal arteries were hardly demonstrable except for extremely vague chorioidal vessels, in the layer of the pigmented epithelium which had a puce-like color. Ay contrast, retinal veins were seen in the fundus oculi, as well as whitish optic nerves. The amplitude of the "a" wave in the electroretinogram (ERG) of Ochotona rufescens was only 1/6 that of albino rats or albino rabbits, but the "b" wave was similar in amplitude for all these three species.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. How Far into Europe Did Pikas (Lagomorpha: Ochotonidae) Go during the Pleistocene? New Evidence from Central Iberia.

    PubMed

    Laplana, César; Sevilla, Paloma; Arsuaga, Juan Luis; Arriaza, Mari Carmen; Baquedano, Enrique; Pérez-González, Alfredo; López-Martínez, Nieves

    2015-01-01

    This paper reports the first find of pika remains in the Iberian Peninsula, at a site in central Spain. A fragmented mandible of Ochotona cf. pusilla was unearthed from Layer 3 (deposited some 63.4±5.5 ka ago as determined by thermoluminescence) of the Buena Pinta Cave. This record establishes new limits for the genus geographic distribution during the Pleistocene, shifting the previous edge of its known range southwest by some 500 km. It also supports the idea that, even though Europe's alpine mountain ranges represented a barrier that prevented the dispersal into the south to this and other taxa of small mammals from central and eastern Europe, they were crossed or circumvented at the coldest time intervals of the end of the Middle Pleistocene and of the Late Pleistocene. During those periods both the reduction of the forest cover and the emersion of large areas of the continental shelf due to the drop of the sea level probably provided these species a way to surpass this barrier. The pika mandible was found accompanying the remains of other small mammals adapted to cold climates, indicating the presence of steppe environments in central Iberia during the Late Pleistocene.

  1. How Far into Europe Did Pikas (Lagomorpha: Ochotonidae) Go during the Pleistocene? New Evidence from Central Iberia

    PubMed Central

    Laplana, César; Sevilla, Paloma; Arsuaga, Juan Luis; Arriaza, Mari Carmen; Baquedano, Enrique; Pérez-González, Alfredo

    2015-01-01

    This paper reports the first find of pika remains in the Iberian Peninsula, at a site in central Spain. A fragmented mandible of Ochotona cf. pusilla was unearthed from Layer 3 (deposited some 63.4±5.5 ka ago as determined by thermoluminescence) of the Buena Pinta Cave. This record establishes new limits for the genus geographic distribution during the Pleistocene, shifting the previous edge of its known range southwest by some 500 km. It also supports the idea that, even though Europe’s alpine mountain ranges represented a barrier that prevented the dispersal into the south to this and other taxa of small mammals from central and eastern Europe, they were crossed or circumvented at the coldest time intervals of the end of the Middle Pleistocene and of the Late Pleistocene. During those periods both the reduction of the forest cover and the emersion of large areas of the continental shelf due to the drop of the sea level probably provided these species a way to surpass this barrier. The pika mandible was found accompanying the remains of other small mammals adapted to cold climates, indicating the presence of steppe environments in central Iberia during the Late Pleistocene. PMID:26535576

  2. Artemisia princeps Inhibits Biofilm Formation and Virulence-Factor Expression of Antibiotic-Resistant Bacteria

    PubMed Central

    Choi, Na-Young; Kang, Sun-Young; Kim, Kang-Ju

    2015-01-01

    In this study, we used ethanol extract of A. princeps and investigated its antibacterial effects against MRSA. Ethanol extract of A. princeps significantly inhibited MRSA growth and organic acid production during glucose metabolism at concentrations greater than 1 mg/mL (P < 0.05). MRSA biofilm formation was observed using scanning electron microscopy (SEM) and safranin staining. A. princeps extract was found to inhibit MRSA biofilm formation at concentrations higher than 2 mg/mL significantly (P < 0.05). Bactericidal effects of the A. princeps were observed using confocal laser microscopy, which showed that A. princeps was bactericidal in a dose-dependent manner. Using real-time PCR, expression of mecA, an antibiotic-resistance gene of MRSA, was observed, along with that of sea, agrA, and sarA. A. princeps significantly inhibited mecA, sea, agrA, and sarA, mRNA expression at the concentrations greater than 1 mg/mL (P < 0.05). The phytochemical analysis of A. princeps showed a relatively high content of organic acids and glycosides. The results of this study suggest that the ethanol extract of A. princeps may inhibit proliferation, acid production, biofilm formation, and virulence gene expressions of MRSA, which may be related to organic acids and glycosides, the major components in the extract. PMID:26247012

  3. Genetic characterization of Toxoplasma gondii from Qinghai vole, Plateau pika and Tibetan ground-tit on the Qinghai-Tibet Plateau, China.

    PubMed

    Zhang, Xiao-Xuan; Lou, Zhong-Zi; Huang, Si-Yang; Zhou, Dong-Hui; Jia, Wan-Zhong; Su, Chunlei; Zhu, Xing-Quan

    2013-10-09

    The distribution of genetic diversity of Toxoplasma gondii in wildlife is of interest to understand the transmission of this parasite in the environment. Limited information on T. gondii genotypes has been reported in wildlife in China. The objective of this study was to carry out the genetic characterization of T. gondii isolates from wild animals on the Qinghai-Tibet Plateau. Using PCR and multilocous polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology, we detected genetic diversity of T. gondii isolates from Qinghai vole, Plateau pika and Tibetan ground-tit in these regions. In total, 183 brain tissues of different wild animals, including 48 Qinghai vole (Microtus fuscus), 101 Plateau pika (Ochotona curzoniae) and 34 Tibetan ground-tit (Pseudopodoces humilis), were tested for T. gondii infection. 11 of these were found to be positive for the T. gondii B1 gene by PCR amplification. These positive DNA samples were typed at 10 genetic markers, including 9 nuclear loci (SAG1, 5'-and 3'-SAG2, alternative SAG2, BTUB, GRA6, L358, PK1, c22-8, c29-2), and an apicoplast locus Apico. Six were successfully genotyped at eight or more genetic loci, and were grouped to three distinct genotypes. Four samples belonged to ToxoDB Genotype #10 and the other two samples were identified as two new genotypes (http://toxodb.org/toxo/). To our knowledge, this is the first report of genetic typing of T. gondii isolates in wildlife on the Qinghai-Tibet Plateau, China. The results show that there is a potential risk for the transmission of this parasite through the wildlife in this region.

  4. Genetic characterization of Toxoplasma gondii from Qinghai vole, Plateau pika and Tibetan ground-tit on the Qinghai-Tibet Plateau, China

    PubMed Central

    2013-01-01

    Background The distribution of genetic diversity of Toxoplasma gondii in wildlife is of interest to understand the transmission of this parasite in the environment. Limited information on T. gondii genotypes has been reported in wildlife in China. The objective of this study was to carry out the genetic characterization of T. gondii isolates from wild animals on the Qinghai-Tibet Plateau. Methods Using PCR and multilocous polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology, we detected genetic diversity of T. gondii isolates from Qinghai vole, Plateau pika and Tibetan ground-tit in these regions. Results In total, 183 brain tissues of different wild animals, including 48 Qinghai vole (Microtus fuscus), 101 Plateau pika (Ochotona curzoniae) and 34 Tibetan ground-tit (Pseudopodoces humilis), were tested for T. gondii infection. 11 of these were found to be positive for the T. gondii B1 gene by PCR amplification. These positive DNA samples were typed at 10 genetic markers, including 9 nuclear loci (SAG1, 5’-and 3’-SAG2, alternative SAG2, BTUB, GRA6, L358, PK1, c22-8, c29-2), and an apicoplast locus Apico. Six were successfully genotyped at eight or more genetic loci, and were grouped to three distinct genotypes. Four samples belonged to ToxoDB Genotype #10 and the other two samples were identified as two new genotypes (http://toxodb.org/toxo/). Conclusions To our knowledge, this is the first report of genetic typing of T. gondii isolates in wildlife on the Qinghai-Tibet Plateau, China. The results show that there is a potential risk for the transmission of this parasite through the wildlife in this region. PMID:24192458

  5. The link between independent acquisition of intracellular gamma-endosymbionts and concerted evolution in Tremblaya princeps.

    PubMed

    López-Madrigal, Sergio; Latorre, Amparo; Moya, Andrés; Gil, Rosario

    2015-01-01

    Many insect species establish mutualistic symbiosis with intracellular bacteria that complement their unbalanced diets. The betaproteobacterium "Candidatus Tremblaya" maintains an ancient symbiosis with mealybugs (Hemiptera: Pseudococcidae), which are classified in subfamilies Phenacoccinae and Pseudococcinae. Most Phenacoccinae mealybugs have "Candidatus Tremblaya phenacola" as their unique endosymbiont, while most Pseudococcinae mealybugs show a nested symbiosis (a bacterial symbiont placed inside another one) where every "Candidatus Tremblaya princeps" cell harbors several cells of a gammaproteobacterium. Genomic characterization of the endosymbiotic consortium from Planococcus citri, composed by "Ca. Tremblaya princeps" and "Candidatus Moranella endobia," unveiled several atypical features of the former's genome, including the concerted evolution of paralogous loci. Its comparison with the genome of "Ca. Tremblaya phenacola" PAVE, single endosymbiont of Phenacoccus avenae, suggests that the atypical reductive evolution of "Ca. Tremblaya princeps" could be linked to the acquisition of "Ca. Moranella endobia," which possess an almost complete set of genes encoding proteins involved in homologous recombination. In order to test this hypothesis, we performed comparative genomics between "Ca. Tremblaya phenacola" and "Ca. Tremblaya princeps" and searched for the co-occurrence of concerted evolution and homologous recombination genes in endosymbiotic consortia from four unexplored mealybug species, Dysmicoccus boninsis, Planococcus ficus, Pseudococcus longispinus, and Pseudococcus viburni. Our results support a link between concerted evolution and nested endosymbiosis.

  6. Understanding relationships among abundance, extirpation,and climate at ecoregional scales

    USGS Publications Warehouse

    Beever, Erik A.; Solomon Dubrowski,; ,; ,; J. Long,; ,; A. Mysnberge,; Piekielek, N. B.

    2014-01-01

    Recent research on mountain-dwelling species has illustrated changes in species’ distributional patterns in response to climate change. Abundance of a species will likely provide an earlier warning indicator of change than will occupancy, yet relationships between abundance and climatic factors have received less attention. We tested whether predictors of counts of American pikas (Ochotona princeps) during surveys from the Great Basin region in 1994–1999 and 2003–2008 differed between the two periods. Additionally, we tested whether various modeled aspects of ecohydrology better predicted relative density than did average annual precipitation, and whether risk of site-wide extirpation predicted subsequent population counts of pikas. We observed several patterns of change in pika abundance at range edges that likely constitute early warnings of distributional shifts. Predictors of pika abundance differed strongly between the survey periods, as did pika extirpation patterns previously reported from this region. Additionally, maximum snowpack and growing-season precipitation resulted in better-supported models than those using average annual precipitation, and constituted two of the top three predictors of pika density in the 2000s surveys (affecting pikas perhaps via vegetation). Unexpectedly, we found that extirpation risk positively predicted subsequent population size. Our results emphasize the need to clarify mechanisms underlying biotic responses to recent climate change at organism-relevant scales, to inform management and conservation strategies for species of concern.

  7. Understanding relationships among abundance, extirpation, and climate at ecoregional scales.

    PubMed

    Beever, Erik A; Dobrowski, S Z; Long, J; Mynsberge, A R; Piekielek, N B

    2013-07-01

    Recent research on mountain-dwelling species has illustrated changes in species distributional patterns in response to climate change. Abundance of a species will likely provide an earlier warning indicator of change than will occupancy, yet relationships between abundance and climatic factors have received less attention. We tested whether predictors of counts of American pikas (Ochotona princeps) during surveys from the Great Basin region in 1994-1999 and 2003-2008 differed between the two periods. Additionally, we tested whether various modeled aspects of ecohydrology better predicted relative density than did average annual precipitation, and whether risk of site-wide extirpation predicted subsequent population counts of pikas. We observed several patterns of change in pika abundance at range edges that likely constitute early warnings of distributional shifts. Predictors of pika abundance differed strongly between the survey periods, as did pika extirpation patterns previously reported from this region. Additionally, maximum snowpack and growing-season precipitation resulted in better-supported models than those using average annual precipitation, and constituted two of the top three predictors of pika density in the 2000s surveys (affecting pikas perhaps via vegetation). Unexpectedly, we found that extirpation risk positively predicted subsequent population size. Our results emphasize the need to clarify mechanisms underlying biotic responses to recent climate change at organism-relevant scales, to inform management and conservation strategies for species of concern.

  8. Effects of Artemisia Princeps Supplementation on Bone Metabolism in Ovariectomized Rats.

    PubMed

    Cho, H-J; Kim, J-W; Ju, S-Y; Park, Y-K

    2016-01-01

    The aim of this study was to investigate the effects of Artemisia princeps (AP) extract on bone metabolism and its potential role in the prevention of osteoporosis in ovariectomized rats. Twenty-six female Sprague-Dawley rats were divided into five groups and treated as follows: sham-operated control group (SHAM); ovariectomized control group (OVX), ovariectomized group treated by gavage with 10 mg/kg/day alendronate (ALEN); ovariectomized group treated by gavage with 100 mg/kg/day Artemisia princeps (AP100); ovariectomized group treated by gavage with 300 mg/kg/day Artemisia princeps (AP300). Treatment of ovariectomized rats with AP extracts for 15 weeks prevented the reduction in bone thickness and trabecular bone mineral density caused by urinary Ca and Cr excretion, and also prevented the increase in bone turnover by maintaining the serum Ca/P ratio. As a result, the microarchitecture of the trabecular bone and cortical bone after ovariectomy was markedly improved by administration of AP extracts. In conclusion, AP prevented bone loss and osteoclast activity associated with high bone turnover in ovariectomized rats by controlling the serum Ca/P ratio and through anti-inflammatory and anti-oxidant properties. Our data implicate AP as a promising therapeutic option for the improvement of postmenopausal osteoporosis.

  9. Comparative study of erythrocyte glycolytic enzymes in man and in two species of Lagomorphae. (Ochotona rufescens rufescens and Oryctolagus cuniculus).

    PubMed

    Puget, A; Vergnes, H; Gouarderes, C

    1974-07-01

    The authors made a comparative study of red cell enzyme glycolysis in man and in two species of Lagomorphae, the pika and the rabbit. The activities of the 12 enzymes of Embden-Meyerhoff pathway and of the two dehydrogenases of pentose shunt (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase) were determined. Phosphoglycerate kinase and pyruvate kinase showed quite similar activities in pika erythrocytes and in erythrocytes from human umbilical cord. The levels of these enzymes differed significantly in the pika and in the rabbit. No differences were noted between pyruvate kinases from the rabbit and the neonatal man. The other activities gave values either identical to those found in the adult man or intermediate between the adult and the neonatal man. In the rabbit the levels of glycolitic enzymes were generally lower than in the pika except for lactate dehydrogenase and glycose-6-phosphate dehydrogenase. Some characteristics of erythrocyte metabolism specific to the pika may account for the differences observed in this species. The influence of red cell age cannot explain the variations observed for no significant reticulocytosis was observed in the circulating blood. The percentages found in the pika and the rabbit were essentially identical at determination.

  10. Characterization of the H5N1 Highly Pathogenic Avian Influenza Virus Derived from Wild Pikas in China▿

    PubMed Central

    Zhou, Jiyong; Sun, Wenbo; Wang, Junhua; Guo, Junqing; Yin, Wei; Wu, Nanping; Li, Lanjuan; Yan, Yan; Liao, Ming; Huang, Yu; Luo, Kaijian; Jiang, Xuetao; Chen, Hualan

    2009-01-01

    The highly pathogenic H5N1 avian influenza virus emerged from China in 1996 and has spread across Eurasia and Africa, with a continuous stream of new cases of human infection appearing since the first large-scale outbreak among migratory birds at Qinghai Lake. The role of wild birds, which are the natural reservoirs for the virus, in the epidemiology of the H5N1 virus has raised great public health concern, but their role in the spread of the virus within the natural ecosystem of free-ranging terrestrial wild mammals remains unclear. In this study, we investigated H5N1 virus infection in wild pikas in an attempt to trace the circulation of the virus. Seroepidemiological surveys confirmed a natural H5N1 virus infection of wild pikas in their native environment. The hemagglutination gene of the H5N1 virus isolated from pikas reveals two distinct evolutionary clades, a mixed/Vietnam H5N1 virus sublineage (MV-like pika virus) and a wild bird Qinghai (QH)-like H5N1 virus sublineage (QH-like pika virus). The amino acid residue (glutamic acid) at position 627 encoded by the PB2 gene of the MV-like pika virus was different from that of the QH-like pika virus; the residue of the MV-like pika virus was the same as that of the goose H5N1 virus (A/GS/Guangdong [GD]/1/96). Further, we discovered that in contrast to the MV-like pika virus, which is nonpathogenic to mice, the QH-like pika virus is highly pathogenic. To mimic the virus infection of pikas, we intranasally inoculated rabbits, a species closely related to pikas, with the H5N1 virus of pika origin. Our findings first demonstrate that wild pikas are mammalian hosts exposed to H5N1 subtype avian influenza viruses in the natural ecosystem and also imply a potential transmission of highly pathogenic avian influenza virus from wild mammals into domestic mammalian hosts and humans. PMID:19553321

  11. Characterization of the H5N1 highly pathogenic avian influenza virus derived from wild pikas in China.

    PubMed

    Zhou, Jiyong; Sun, Wenbo; Wang, Junhua; Guo, Junqing; Yin, Wei; Wu, Nanping; Li, Lanjuan; Yan, Yan; Liao, Ming; Huang, Yu; Luo, Kaijian; Jiang, Xuetao; Chen, Hualan

    2009-09-01

    The highly pathogenic H5N1 avian influenza virus emerged from China in 1996 and has spread across Eurasia and Africa, with a continuous stream of new cases of human infection appearing since the first large-scale outbreak among migratory birds at Qinghai Lake. The role of wild birds, which are the natural reservoirs for the virus, in the epidemiology of the H5N1 virus has raised great public health concern, but their role in the spread of the virus within the natural ecosystem of free-ranging terrestrial wild mammals remains unclear. In this study, we investigated H5N1 virus infection in wild pikas in an attempt to trace the circulation of the virus. Seroepidemiological surveys confirmed a natural H5N1 virus infection of wild pikas in their native environment. The hemagglutination gene of the H5N1 virus isolated from pikas reveals two distinct evolutionary clades, a mixed/Vietnam H5N1 virus sublineage (MV-like pika virus) and a wild bird Qinghai (QH)-like H5N1 virus sublineage (QH-like pika virus). The amino acid residue (glutamic acid) at position 627 encoded by the PB2 gene of the MV-like pika virus was different from that of the QH-like pika virus; the residue of the MV-like pika virus was the same as that of the goose H5N1 virus (A/GS/Guangdong [GD]/1/96). Further, we discovered that in contrast to the MV-like pika virus, which is nonpathogenic to mice, the QH-like pika virus is highly pathogenic. To mimic the virus infection of pikas, we intranasally inoculated rabbits, a species closely related to pikas, with the H5N1 virus of pika origin. Our findings first demonstrate that wild pikas are mammalian hosts exposed to H5N1 subtype avian influenza viruses in the natural ecosystem and also imply a potential transmission of highly pathogenic avian influenza virus from wild mammals into domestic mammalian hosts and humans.

  12. Characterization of H7N2 Avian Influenza Virus in Wild Birds and Pikas in Qinghai-Tibet Plateau Area

    PubMed Central

    Su, Shuo; Xing, Gang; Wang, Junhua; Li, Zengkui; Gu, Jinyan; Yan, Liping; Lei, Jing; Ji, Senlin; Hu, Boli; Gray, Gregory C.; Yan, Yan; Zhou, Jiyong

    2016-01-01

    Qinghai Lake is a major migrating bird breeding site that has experienced several recent highly pathogenic avian influenza virus (HPAIV) epizootics. From 2006 to 2009 we studied Qinghai’s wild birds and pikas for evidence of AIV infections. We sampled 941 healthy wild animals and isolated seventeen H7N2 viruses (eight from pikas and nine from wild birds). The H7N2 viruses were phylogenetically closely related to each other and to viruses isolated in Hong Kong in the 1970s. We determined the pathogenicity of the H7N2 viruses by infecting chickens and mice. Our results suggest that pikas might play an important role in the ecology of AIVs, acting as intermediate hosts in which viruses become more adapted to mammals. Our findings of AI infection in pikas are consistent with previous observations and raise the possibility that pikas might play a previously unrecognized role in the ecology of AIVs peridomestic aquatic environments. PMID:27553660

  13. A novel rabies vaccine based-on toll-like receptor 3 (TLR3) agonist PIKA adjuvant exhibiting excellent safety and efficacy in animal studies

    SciTech Connect

    Zhang, Yi; Zhang, Shoufeng; Li, Wei; Hu, Yuchi; Zhao, Jinyan; Liu, Fang; Lin, Haixiang; Liu, Yuan; Wang, Liliang; Xu, Shu; Hu, Rongliang; Shao, Hui; Li, Lietao

    2016-02-15

    Vaccination alone is not sufficiently effective to protect human from post-exposure rabies virus infection due to delayed generation of rabies virus neutralizing antibodies and weak cellular immunity. Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as adjuvant of rabies vaccine. The efficacy and safety of PIKA rabies vaccine were evaluated. The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group (control) was 20–30%. According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to develop next-generation rabies vaccine and encourage the start of clinical studies. - Highlights: • Vaccination alone is not effective to protect human from rabies virus infection due to delayed generation of rabies virus neutralizing antibodies (RVNA) and weak cellular immunity. • Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as an adjuvant of rabies vaccine. • The efficacy and safety of PIKA rabies vaccine was evaluated in mice. • The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. • After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group was only 20–30%. • According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. • Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to

  14. Parasite structure of the Ocean Whitefish Caulolatilus princeps from Baja California, México (East Pacific)

    NASA Astrophysics Data System (ADS)

    Rodríguez-Santiago, M. A.; Rosales-Casián, J. A.

    2011-06-01

    The metazoan parasite fauna of Caulolatilus princeps from northern Baja California, Mexico is quantitatively described for the first time. Further, the ecological aspects of prevalence, abundance, and intensity of infection are examined through an annual cycle. Six parasite species were recorded; 2 ectoparasites (1 monogenean and 1 copepod) and 4 endoparasites (2 digeneans and 2 nematodes). The digeneans Choanodera caulolatili and Bianium plicitum, the nematodes Anisakis sp. and Hysterothylacium sp., and the copepod Hatschekia sp. set new geographical and host records. The highest values of prevalence and abundance were in Anisakis sp. (prevalence = 93.3%, abundance = 12.4 ± 4.7 ind/host) and in Hysterothylacium sp. (prevalence = 86.6%, abundance = 16.5 ± 3.4 ind/host). The mean intensity of infection showed maximum values in summer (August = 14.2) and minimums in winter (February = 4.2). The mean intensity was higher in Hatschekia sp. (20.3 ± 7.8) followed by Hysterothylacium sp. (18.6 ± 1.4) and Anisakis sp. (12.9 ± 2.2). Larval stages of Anisakis and Hysterothylacium were particularly important due to their high abundance and prevalence, because they represent a human health risk (anisakiasis). In addition, the relationships between the metazoan parasites of C. princeps and host size and weight, fish condition and water temperature (bottom) are discussed.

  15. Anticoagulant and Antiplatelet Activities of Artemisia princeps Pampanini and Its Bioactive Components

    PubMed Central

    Ryu, Ri; Jung, Un Ju; Kim, Hye-jin; Lee, Wonhwa; Bae, Jong-Sup; Park, Yong Bok; Choi, Myung-Sook

    2013-01-01

    Artemisia princeps Pampanini (AP) has been used as a traditional medicine in Korea, China and Japan and reported to exhibit various beneficial biological effects including anti-inflammatory, antioxidant, anti-atherogenic and lipid lowering activities; however, its antiplatelet and anticoagulant properties have not been studied. In the present study, we evaluated the effects of an ethanol extract of Artemisia princeps Pampanini (EAP) and its major flavonoids, eupatilin and jaceosidin, on platelet aggregation and coagulation. To determine the antiplatelet activity, arachidonic acid (AA)-, collagen- and ADP (adenosine diphosphate)-induced platelet aggregation were examined along with serotonin and thromboxane A2 (TXA2) generation in vitro. The anticoagulant activity was determined by monitoring the activated partial thromboplastin time (aPTT) and prothrombin time (PT) in vitro. The data showed that EAP and its major flavonoids, eupatilin and jaceosidin, significantly reduced AA-induced platelet aggregation and the generation of serotonin and TXA2, although no significant change in platelet aggregation induced by collagen and ADP was observed. Moreover, EAP significantly prolonged the PT and aPTT. The PT and/or aPTT were significantly increased in the presence of eupatilin and jaceosidin. Thus, these results suggest that EAP may have the potential to prevent or improve thrombosis by inhibiting platelet activation and blood coagulation. PMID:24471130

  16. Phytochemical Characteristics of Seeds and Its Effects on the Intestinal Motility and Toxicity of Joannesia princeps.

    PubMed

    Araújo, Adriano Cressoni; Guiguer, Élen Landgraf; Barbalho, Sandra Maria; Bueno, Patrícia C S; Lopes, Juliana Agostinho; da Silva, Bruna Ferreira; Girotto, Letícia Cabrini; de Paula, Marina Guirro; Zeber, Paulo Vitor; de Alvares Goulart, Ricardo

    2016-01-01

    Joannesia princeps is a plant commonly used in folk medicine as laxative for menstrual discomfort and as antihelminthic and antimicrobial to reduce edema and improve tissue healing. The seeds are used in many regions of Brazil as laxative; however, studies are needed to confirm its effectiveness and safety. Thus, the aim of this study was to evaluate the effects of using seeds of this plant on intestinal motility of Wistar rats, evaluate the effects and acute toxicity of its management, as well as determine its phytochemical profile. The evaluation of the effect on the intestinal motility was performed according to the model described by Michelin and Salgado (2004) with modifications. For the evaluation of acute toxicity, we used the model described by Craveiro et al. (2008) and Goloni et al. (2005), and for the analysis of the presence of alkaloids, flavonoids, anthraquinones, steroids, and other components, we used the method described by Carvalho et al. (2006). The results showed that J. princeps exhibits laxative effects similar to those of Senna species such as Cassia angustifolia and the phytochemical analysis of ethanol and aqueous extracts showed the presence of alkaloids, triterpenes, and/or steroids compounds. Acute toxicity showed in the first 12 h: piloerection, contortion, decreased respiratory rate, diarrhea, and weight loss. After this period, these changes were no longer observed. It was concluded that the seeds of this plant have potential laxative activity, confirming the popular use and that the dose of 5 g/kg can be considered safe for consumption.

  17. Development of monacolin K-enriched ganghwayakssuk (Artemisia princeps Pamp.) by fermentation with Monascus pilosus.

    PubMed

    Lee, Dong Sub; Lee, Inhyung

    2012-07-01

    Monacolin K-enriched ganghwayakssuk (Artemisia princeps Pamp.) was developed by fermentation with Monascus sp. Among the 15 Monascus spp. isolated previously from Monascus fermentation products, Monascus pilosus KMU108 produced 2,219 mg/kg of monacolin K during ganghwayakssuk fermentation with no detectable citrinin. The optimum concentrations of ganghwayakssuk and glucose determined from the response surface methodology (RSM) design were 2.2% and 3.8%, respectively. By applying these conditions, the monacolin K productivity was increased to 3,007 mg/kg after 15 days of fermentation. On the other hand, other characteristics such as the total content of flavonoids and phenolic compounds, and the antioxidant activity were relatively unchanged. Therefore, Monascusfermented ganghwayakssuk is an excellent biomaterial for the development of functional foods because of its high level of monacolin K, known to lower cholesterol levels.

  18. Inhibitor screening of lactate dehydrogenase C4 from black-lipped pika in the Western Sichuan Plateau.

    PubMed

    Zhang, Qinglian; He, Qinghua; Xue, Fulai; Ma, Jinhu

    2014-01-01

    Studies indicated that lactate dehydrogenase C4 (LDH-C4) was a good target protein for development of contraceptive drugs. Virtual screening and in vitro enzyme assay using pika LDH-C4 as target protein revealed NSC61610, NSC215718, and NSC345647 with Ki of 7.8, 27, and 41 μM separately. This study might be helpful for development of pika contraceptive drugs.

  19. Role of glutamate and serotonin on the hypoxic ventilatory response in high-altitude-adapted plateau Pika.

    PubMed

    Bai, Zhenzhong; Voituron, Nicolas; Wuren, Tana; Jeton, Florine; Jin, Guoen; Marchant, Dominique; Richalet, Jean-Paul; Ge, Ri-Li; Pichon, Aurélien P

    2015-07-01

    The highland "plateau Pika" is considered to be adapted to chronic hypoxia. We hypothesized that glutamate N-methyl-D-aspartate (NMDA) and non-NMDA receptors, nitric oxide (NO) synthase, and serotonin are involved in hypoxic ventilatory response (HVR) in Pikas. We tested the effects of NMDA (memantine) and non-NMDA receptors (DNQX) antagonists, NO synthase inhibitor (L-NAME), and selective serotonin reuptake inhibitors (fluoxetine) on ventilation and HVR in Pikas. Ventilatory parameters were measured before and after drug (or vehicle) injections in conscious Pikas at their natural living altitude (PIO2 86 mmHg) and after a hypoxic challenge (PIO2 57 mmHg, 3 min) to assess the influence of peripheral chemoreceptor on HVR. Minute ventilation (VI) and tidal volume (Vt) increased during hypoxic challenge after vehicle injection, whereas the Ti/Ttot ratio remained unchanged. The increase in VI and Vt observed with vehicle at PIO2-57, when compared with PIO2-86, was inhibited after memantine and fluoxetine injection, whereas the DNQX injection increased HVR. At PIO2-57, L-NAME induced an increase in the Ti/Ttot ratio when compared with vehicle. Therefore, the glutamate through NMDA-R/AMPA receptor bindings and serotonin pathway are implicated at the peripheral chemoreceptor level in HVR in Pikas. However, NO influences the ventilatory pattern of Pikas at their habitual living altitude.

  20. Reproduction and embryonic development in two species of squaliform sharks, Centrophorus granulosus and Etmopterus princeps: Evidence of matrotrophy?

    NASA Astrophysics Data System (ADS)

    Cotton, Charles F.; Dean Grubbs, R.; Dyb, Jan E.; Fossen, Inge; Musick, John A.

    2015-05-01

    Modes of reproduction and embryonic development vary greatly among the elasmobranchs, and prior studies have suggested that the energetic toll of embryogenesis in lecithotrophic species depletes embryonic organic matter by 20% or more. Matrotrophic species experience a lesser reduction or an increase in organic matter during embryogenesis. To investigate the maternal-embryonic nutritional relationship, we measured changes in organic matter from fertilization to near-parturition in embryos of Centrophorus granulosus and Etmopterus princeps. Embryos of C. granulosus experienced a reduction of 19.5% in organic matter, while E. princeps embryos experienced a reduction of 7.7% in organic matter over the course of embryonic development, suggesting some level of matrotrophy occurs, particularly for the latter species. Uterine villi were present in both species and developed concurrently with the embryos, increasing in length and thickness while becoming progressively vascularized. Embryos of C. granulosus were dissected to track the partitioning of water, organic matter, and inorganic matter to the liver, external yolk sac, internal yolk sac, digestive tract, and evicerated body throughout development. Mating was aseasonal for both species and spatially-mediated segregation by sex and maturity stage was observed. Ovarian cycles were concurrent for C. granulosus and consecutive for E. princeps. Size at maturity for C. granulosus was determined to be 111 cm TL for males and 143 cm TL for females, with an average fecundity of 5.3 embryos (range=4-7). Size at maturity for E. princeps was determined to be 56.5 cm TL for males and 61 cm TL for females north of the Azores and 54 cm TL for males and 69 cm TL for females near the Charlie Gibbs Fracture Zone. Average fecundity was 11.2 embryos (range=7-18) for this species. This is the first reporting of reproductive parameters for these two species, and the information provided will be valuable for informing stock assessment

  1. Lagomorphs (rabbits, pikas and hares) do not use telomere-directed replicative aging in vitro.

    PubMed

    Forsyth, Nicholas R; Elder, Frederick F B; Shay, Jerry W; Wright, Woodring E

    2005-01-01

    Telomere shortening is used for replicative aging in primates and ungulates but not rodents. We examined telomere biology in rabbits to expand the comparative biology of telomere-directed replicative senescence within mammals. The order Lagomorpha consists of two families; Leporidae and Ochotonidae. We examined telomere biology in species representing three leporid genera (European White Rabbit, Black-tailed Jack Rabbit, and Swamp Rabbit) and the monotypic ochotonid genus (North American Pika). Of the leporids one species was a laboratory strain and the others were wild caught. The leporids neither exhibited cellular senescence after sustained periods in culture nor displayed detectable telomerase activity. Continued culture was possible because of their extremely long telomeric arrays. Immunofluorescence showed robust telomere signals at chromosome ends and significant internal chromosomal staining in some instances. Pika was unique in displaying endogenous telomerase activity throughout time in culture. These results show that it is unlikely that lagomorphs use telomere shortening and replicative senescence as a tumor protective mechanism.

  2. Allohumibacter endophyticus gen. nov., sp. nov., isolated from the root of wild Artemisia princeps (mugwort).

    PubMed

    Ri Kim, Yu; Kim, Tae-Su; Han, Ji-Hye; Joung, Yochan; Park, Jisun; Kim, Seung Bum

    2016-04-01

    A novel actinobacterium designated strain MWE-A11T was isolated from the root of wild Artemisia princeps (mugwort). The isolate was aerobic, Gram-stain-positive and short rod-shaped, and the colonies were yellow and circular with entire margin. Strain MWE-A11T grew at 15-37 °C and pH 6.0-8.0. The predominant isoprenoid quinones were MK-11 and MK-10. The predominant fatty acids were anteiso-C15:0 and iso-C16:0, and the DNA G+C content was 68.8 mol%. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The peptidoglycan contained 2,4-diaminobutyric acid as the diagnostic diamino acid, and the acyl type was glycolyl. Phylogenetic analyses based on 16S rRNA gene sequence comparisons indicated that strain MWE-A11T was affiliated with the family Microbacteriaceae, and was most closely related to the type strains of Humibacter antri (96.4% 16S rRNA gene sequence similarity), Herbiconiux moechotypicola (96.3%), Leifsonia soli (96.3%), Leifsonia lichenia (96.2%), Leifsonia xyli subsp. cynodontis (96.1%), Microbacterium testaceum (96.0%) and Humibacter albus (96.0%). However, the combination of chemotaxonomic properties clearly distinguished strain MWE-A11T from the related taxa at genus level. Accordingly, Allohumibacter endophyticus gen. nov., sp. nov. is proposed to accommodate a new member of the family Microbacteriaceae. The type strain of the type species is MWE-A11T (=JCM 19371T=KCTC 29232T).

  3. A multifunctional, synthetic Gaussia princeps luciferase reporter for live imaging of Candida albicans infections.

    PubMed

    Enjalbert, Brice; Rachini, Anna; Vediyappan, Govindsamy; Pietrella, Donatella; Spaccapelo, Roberta; Vecchiarelli, Anna; Brown, Alistair J P; d'Enfert, Christophe

    2009-11-01

    Real-time monitoring of the spatial and temporal progression of infection/gene expression in animals will contribute greatly to our understanding of host-pathogen interactions while reducing the number of animals required to generate statistically significant data sets. Sensitive in vivo imaging technologies can detect low levels of light emitted from luciferase reporters in vivo, but the existing reporters are not optimal for fungal infections. Therefore, our aim was to develop a novel reporter system for imaging Candida albicans infections that overcomes the limitations of current luciferase reporters for this major fungal pathogen. This luciferase reporter was constructed by fusing a synthetic, codon-optimized version of the Gaussia princeps luciferase gene to C. albicans PGA59, which encodes a glycosylphosphatidylinositol-linked cell wall protein. Luciferase expressed from this PGA59-gLUC fusion (referred to as gLUC59) was localized at the C. albicans cell surface, allowing the detection of luciferase in intact cells. The analysis of fusions to strong (ACT1 and EFT3), oxidative stress-induced (TRX1, TRR1, and IPF9996), and morphogenesis-dependent (HWP1) promoters confirmed that gLUC59 is a convenient and sensitive reporter for studies of gene regulation in yeast or hyphal cells, as well as a flexible screening tool. Moreover, the ACT1-gLUC59 fusion represented a powerful tool for the imaging of disease progression in superficial and subcutaneous C. albicans infections. gLUC59 and related cell surface-exposed luciferase reporters might find wide applications in molecular biology, cell biology, pathobiology, and high-throughput screens.

  4. A novel rabies vaccine based-on toll-like receptor 3 (TLR3) agonist PIKA adjuvant exhibiting excellent safety and efficacy in animal studies.

    PubMed

    Zhang, Yi; Zhang, Shoufeng; Li, Wei; Hu, Yuchi; Zhao, Jinyan; Liu, Fang; Lin, Haixiang; Liu, Yuan; Wang, Liliang; Xu, Shu; Hu, Rongliang; Shao, Hui; Li, Lietao

    2016-02-01

    Vaccination alone is not sufficiently effective to protect human from post-exposure rabies virus infection due to delayed generation of rabies virus neutralizing antibodies and weak cellular immunity. Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as adjuvant of rabies vaccine. The efficacy and safety of PIKA rabies vaccine were evaluated. The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. After viral challenge, PIKA rabies vaccine protected 70-80% of animals, while the survival rate of non-adjuvant vaccine group (control) was 20-30%. According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to develop next-generation rabies vaccine and encourage the start of clinical studies.

  5. Changes in the morphology and protein expression of germ cells and Sertoli cells in plateau pikas testes during non-breeding season.

    PubMed

    Liu, Ming; Cao, Guangming; Zhang, Yanming; Qu, Jiapeng; Li, Wei; Wan, Xinrong; Li, Yu-Xia; Zhang, Zhibin; Wang, Yan-Ling; Gao, Fei

    2016-03-04

    Plateau pikas are seasonally breeding small herbivores that inhabit the meadow ecosystem of the Qinghai-Tibetan Plateau. Testis regression in plateau pikas begins in early June, and the male pikas are completely infertile, with a dramatically reduced testis size, in late July. In this study, a decreased germ cell number in the testes was first noted in early June. By late June, only Sertoli cells and a small number of spermatogonia remained. Interestingly, large gonocyte-like germ cells were observed in early July. In late July, the number of gonocyte-like cells per tubule increased significantly, and most of the Sertoli cell nuclei moved to and clustered in the center of the seminiferous tubules. The gonocyte-like germ cells and Sertoli cells began to express AP-2γ and anti-Mullerian hormone (AMH) proteins, which were detected in the germ cells and Sertoli cells of juvenile pikas but not in adult testes. Simultaneously, LC3 puncta dramatically increased in the seminiferous tubules of the pikas' testes during the non-breeding season. Our study found that spermatogonia and Sertoli cells in non-breeding adult pikas morphologically resembled those in juvenile pikas and expressed specific markers, indicating that de-differentiation-like transitions may occur during this process.

  6. Critical Analysis of a Social and Scientific Moral Dilemma: Fifth Graders and Veterans Respond to "Hiroshima No Pika."

    ERIC Educational Resources Information Center

    Storey, Dee

    This document presents results of a survey studying the Japanese picture book, "Hiroshima No Pika." The story aptly captures how a family of three find their lives shattered in a matter of seconds when the atomic bomb is dropped on Hiroshima (Japan) in World War II. Issues presented in the story are: (1) immediate survival in the face of…

  7. Too hot to trot? evaluating the effects of wildfire on patterns of occupancy and abundance for a climate-sensitive habitat-specialist

    USGS Publications Warehouse

    Varner, Johanna; Lambert, Mallory S.; Horns, Joshua J.; Laverty, Sean; Dizney, Laurie; Beever, Erik; Dearing, M. Denise

    2015-01-01

    Wildfires are increasing in frequency and severity as a result of climate change in many ecosystems; however, effects of altered disturbance regimes on wildlife remain poorly quantified. Here, we leverage an unexpected opportunity to investigate how fire affects the occupancy and abundance of a climate-sensitive habitat specialist, the American pika (Ochotona princeps). We determine the effects of a fire on microclimates within talus and explore habitat factors promoting persistence and abundance in fire-affected habitat. During the fire, temperatures in talus interstices remained below 19°C, suggesting that animals could have survived in situ. Within 2 years, pikas were widely distributed throughout burned areas and did not appear to be physiologically stressed at severely burned sites. Furthermore, pika densities were better predicted by topographic variables known to affect this species than by metrics of fire severity. This widespread distribution may reflect quick vegetation recovery and the fact that the fire did not alter the talus microclimates in the following years. Together, these results highlight the value of talus as a thermal refuge for small animals during and after fire. They also underscore the importance of further study in individual species’ responses to typical and altered disturbance regimes.

  8. Changes in the morphology and protein expression of germ cells and Sertoli cells in plateau pikas testes during non-breeding season

    PubMed Central

    Liu, Ming; Cao, Guangming; Zhang, Yanming; Qu, Jiapeng; Li, Wei; Wan, Xinrong; Li, Yu-xia; Zhang, Zhibin; Wang, Yan-ling; Gao, Fei

    2016-01-01

    Plateau pikas are seasonally breeding small herbivores that inhabit the meadow ecosystem of the Qinghai-Tibetan Plateau. Testis regression in plateau pikas begins in early June, and the male pikas are completely infertile, with a dramatically reduced testis size, in late July. In this study, a decreased germ cell number in the testes was first noted in early June. By late June, only Sertoli cells and a small number of spermatogonia remained. Interestingly, large gonocyte-like germ cells were observed in early July. In late July, the number of gonocyte-like cells per tubule increased significantly, and most of the Sertoli cell nuclei moved to and clustered in the center of the seminiferous tubules. The gonocyte-like germ cells and Sertoli cells began to express AP-2γ and anti-Mullerian hormone (AMH) proteins, which were detected in the germ cells and Sertoli cells of juvenile pikas but not in adult testes. Simultaneously, LC3 puncta dramatically increased in the seminiferous tubules of the pikas’ testes during the non-breeding season. Our study found that spermatogonia and Sertoli cells in non-breeding adult pikas morphologically resembled those in juvenile pikas and expressed specific markers, indicating that de-differentiation-like transitions may occur during this process. PMID:26939551

  9. Anti-scratching behavioral effect of the essential oil and phytol isolated from Artemisia princeps Pamp. in mice.

    PubMed

    Ryu, Kwon-Ryeol; Choi, Jong-Youl; Chung, Suna; Kim, Dong-Hyun

    2011-01-01

    The anti-scratching behavioral effect of the essential oil and phytol isolated from Artemisia princeps Pamp. (AP, family Asteraceae), which is widely used in traditional medicine for inflammatory diseases, was investigated IN VIVO. Treatment of mice with AP essential oil (APEO) and phytol inhibited histamine- and compound 48/80-induced scratching behaviors. The anti-scratching behavioral effects of APEO and phytol are in proportion to their vascular permeability-inhibitory effects. These agents also inhibited the level of allergic cytokines, IL-4, and TNF- α, and the activation of transcription factors, NF- κB and c-jun (AP-1), in histamine-treated skin tissues. Based on these results, APEO and phytol may improve scratching behavior in skin by inhibiting the expression of allergic cytokines via the regulation of NF- κB and AP-1 activation. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Developing a protocol for long-term population monitoring and habitat projections for a climate-sensitive sentinel species to track ecosystem change and species range shifts

    NASA Astrophysics Data System (ADS)

    Beers, A.

    2016-12-01

    As a response to ongoing climate change, many species have started to shift their ranges poleward and toward higher elevations and mountain environments are predicted to experience especially rapid climatic changes. Because of this, there is likely a greater risk of habitat loss and local extinctions for species at high elevations compared to species at lower elevations. Among those potentially threatened habitat specialists is the American pika (Ochotona princeps), a climate sensitive indicator of climate change effects which may already be experiencing climate driven extirpations. Pikas are considered sentinels, indicators of greater ecosystem change. Changes in their distribution speaks to changes in availability of resources they require and shifts in the environment. Pika presence is closely tied to sub-surface ice features that act as a temperature buffer and water source. Those sub-surface ice features are critical in water cycling and long-term water storage and drive downstream hydrological and ecological processes. Understanding how this species responds to climate change therefore provides a model to inform landscape level conservation and management decisions. Pikas may be particularly vulnerable in parts of Colorado, including Rocky Mountain National Park (ROMO) and the Niwot Ridge LTER (NWT), where they may face population collapse as habitat suitability and connectivity both decline in response to various possible climate change scenarios, in large part because of cold stress and declining functional connectivity. Because of their potential role as an ecosystem indicator, their risk for decline, and how limitations to their survival likely vary across their range, management groups can use place based models of habitat suitability for pikas or other sentinel species in designing long term monitoring protocols to detect ecosystem responses to climate change. In this project we used remotely sensed data, occupancy surveys, and a random tessellation

  11. Genetic Evidence for Restricted Dispersal along Continuous Altitudinal Gradients in a Climate Change-Sensitive Mammal: The American Pika

    PubMed Central

    Henry, Philippe; Sim, Zijian; Russello, Michael A.

    2012-01-01

    When faced with rapidly changing environments, wildlife species are left to adapt, disperse or disappear. Consequently, there is value in investigating the connectivity of populations of species inhabiting different environments in order to evaluate dispersal as a potential strategy for persistence in the face of climate change. Here, we begin to investigate the processes that shape genetic variation within American pika populations from the northern periphery of their range, the central Coast Mountains of British Columbia, Canada. At these latitudes, pikas inhabit sharp elevation gradients ranging from sea level to 1500 m, providing an excellent system for studying the effects of local environmental conditions on pika population genetic structure and gene flow. We found low levels of neutral genetic variation compared to previous studies from more southerly latitudes, consistent with the relatively recent post-glacial colonization of the study location. Moreover, significant levels of inbreeding and marked genetic structure were detected within and among sites. Although low levels of recent gene flow were revealed among elevations within a transect, potentially admixed individuals and first generation migrants were identified using discriminant analysis of principal components between populations separated by less than five kilometers at the same elevations. There was no evidence for historical population decline, yet there was signal for recent demographic contractions, possibly resulting from environmental stochasticity. Correlative analyses revealed an association between patterns of genetic variation and annual heat-to-moisture ratio, mean annual precipitation, precipitation as snow and mean maximum summer temperature. Changes in climatic regimes forecasted for the region may thus potentially increase the rate of population extirpation by further reducing dispersal between sites. Consequently, American pika may have to rely on local adaptations or phenotypic

  12. Genetic evidence for restricted dispersal along continuous altitudinal gradients in a climate change-sensitive mammal: the American Pika.

    PubMed

    Henry, Philippe; Sim, Zijian; Russello, Michael A

    2012-01-01

    When faced with rapidly changing environments, wildlife species are left to adapt, disperse or disappear. Consequently, there is value in investigating the connectivity of populations of species inhabiting different environments in order to evaluate dispersal as a potential strategy for persistence in the face of climate change. Here, we begin to investigate the processes that shape genetic variation within American pika populations from the northern periphery of their range, the central Coast Mountains of British Columbia, Canada. At these latitudes, pikas inhabit sharp elevation gradients ranging from sea level to 1500 m, providing an excellent system for studying the effects of local environmental conditions on pika population genetic structure and gene flow. We found low levels of neutral genetic variation compared to previous studies from more southerly latitudes, consistent with the relatively recent post-glacial colonization of the study location. Moreover, significant levels of inbreeding and marked genetic structure were detected within and among sites. Although low levels of recent gene flow were revealed among elevations within a transect, potentially admixed individuals and first generation migrants were identified using discriminant analysis of principal components between populations separated by less than five kilometers at the same elevations. There was no evidence for historical population decline, yet there was signal for recent demographic contractions, possibly resulting from environmental stochasticity. Correlative analyses revealed an association between patterns of genetic variation and annual heat-to-moisture ratio, mean annual precipitation, precipitation as snow and mean maximum summer temperature. Changes in climatic regimes forecasted for the region may thus potentially increase the rate of population extirpation by further reducing dispersal between sites. Consequently, American pika may have to rely on local adaptations or phenotypic

  13. PRINCEPS: A computer-based approach to the structural description and recognition of trends within structural databases, and its application to the Ce-Ni-Si System

    SciTech Connect

    Guo, Yiming; Fredrickson, Daniel C.

    2016-04-01

    Intermetallic crystal structures offer an enormous structural diversity, with an endless array of structural motifs whose connection to stability and physical properties are often mysterious. Making sense of the often complex crystal structures that arise here, developing a clear structural description, and identifying connections to other phases can be laborious and require an encyclopedic knowledge of structure types. In this Article, we present PRINCEPS, an algorithm based on a new coordination environment projection scheme that facilitates the structural analysis and comparison of such crystal structures. We demonstrate the potential of this approach by applying it to the complex Ce-Ni-Si ternary system, whose 17 binary and 21 ternary phases would present a daunting challenge to one seeking to understand the system by manual inspection (but has nonetheless been well-described through the heroic efforts of previous researchers). With the help of PRINCEPS, most of the ternary phases in this system can be rationalized as intergrowths of simple structural fragments, and grouped into a handful of structural series (with some outliers). Lastly, these results illustrate how the PRINCEPS approach can be used to organize a vast collection of crystal structures into structurally meaningful families, and guide the description of complex atomic arrangements.

  14. PRINCEPS: A computer-based approach to the structural description and recognition of trends within structural databases, and its application to the Ce-Ni-Si System

    DOE PAGES

    Guo, Yiming; Fredrickson, Daniel C.

    2016-04-01

    Intermetallic crystal structures offer an enormous structural diversity, with an endless array of structural motifs whose connection to stability and physical properties are often mysterious. Making sense of the often complex crystal structures that arise here, developing a clear structural description, and identifying connections to other phases can be laborious and require an encyclopedic knowledge of structure types. In this Article, we present PRINCEPS, an algorithm based on a new coordination environment projection scheme that facilitates the structural analysis and comparison of such crystal structures. We demonstrate the potential of this approach by applying it to the complex Ce-Ni-Si ternarymore » system, whose 17 binary and 21 ternary phases would present a daunting challenge to one seeking to understand the system by manual inspection (but has nonetheless been well-described through the heroic efforts of previous researchers). With the help of PRINCEPS, most of the ternary phases in this system can be rationalized as intergrowths of simple structural fragments, and grouped into a handful of structural series (with some outliers). Lastly, these results illustrate how the PRINCEPS approach can be used to organize a vast collection of crystal structures into structurally meaningful families, and guide the description of complex atomic arrangements.« less

  15. Distribution of a climate-sensitive species at an interior range margin

    USGS Publications Warehouse

    Ray, Chris; Beever, Erik; Rodhouse, Thomas J.

    2016-01-01

    Advances in understanding the factors that limit a species’ range, particularly in the context of climate change, have come disproportionately through investigations at range edges or margins. The margins of a species’ range might often correspond with anomalous microclimates that confer habitat suitability where the species would otherwise fail to persist. We addressed this hypothesis using data from an interior, climatic range margin of the American pika (Ochotona princeps), an indicator of relatively cool, mesic climates in rocky habitats of western North America. Pikas in Lava Beds National Monument, northeastern California, USA, occur at elevations much lower than predicted by latitude and longitude. We hypothesized that pika occurrence within Lava Beds would be associated primarily with features such as “ice caves” in which sub-surface ice persists outside the winter months. We used data loggers to monitor sub-surface temperatures at cave entrances and at non-cave sites, confirming that temperatures were cooler and more stable at cave entrances. We surveyed habitat characteristics and evidence of pika occupancy across a random sample of cave and non-cave sites over a 2-yr period. Pika detection probability was high (~0.97), and the combined occupancy of cave and non-cave sites varied across the 2 yr from 27% to 69%. Contrary to our hypothesis, occupancy was not higher at cave sites. Vegetation metrics were the best predictors of site use by pikas, followed by an edge effect and elevation. The importance of vegetation as a predictor of pika distribution at this interior range margin is congruent with recent studies from other portions of the species’ range. However, we caution that vegetation composition depends on microclimate, which might be the proximal driver of pika distribution. The microclimates available in non-cave crevices accessible to small animals have not been characterized adequately for lava landscapes. We advocate innovation in the

  16. Testing alternative models of climate-mediated extirpations.

    PubMed

    Beever, Erik A; Ray, Chris; Mote, Philip W; Wilkening, Jennifer L

    2010-01-01

    Biotic responses to climate change will vary among taxa and across latitudes, elevational gradients, and degrees of insularity. However, due to factors such as phenotypic plasticity, ecotypic variation, and evolved tolerance to thermal stress, it remains poorly understood whether losses should be greatest in populations experiencing the greatest climatic change or living in places where the prevailing climate is closest to the edge of the species' bioclimatic envelope (e.g., at the hottest, driest sites). Research on American pikas (Ochotona princeps) in montane areas of the Great Basin during 1994-1999 suggested that 20th-century population extirpations were predicted by a combination of biogeographic, anthropogenic, and especially climatic factors. Surveys during 2005-2007 documented additional extirpations and within-site shifts of pika distributions at remaining sites. To evaluate the evidence in support of alternative hypotheses involving effects of thermal stress on pikas, we placed temperature sensors at 156 locations within pika habitats in the vicinity of 25 sites with historical records of pikas in the Basin. We related these time series of sensor data to data on ambient temperature from weather stations within the Historical Climate Network. We then used these highly correlated relationships, combined with long-term data from the same weather stations, to hindcast temperatures within pika habitats from 1945 through 2006. To explain patterns of loss, we posited three alternative classes of direct thermal stress: (1) acute cold stress (number of days below a threshold temperature); (2) acute heat stress (number of days above a threshold temperature); and (3) chronic heat stress (average summer temperature). Climate change was defined as change in our thermal metrics between two 31-yr periods: 1945-1975 and 1976-2006. We found that patterns of persistence were well predicted by metrics of climate. Our best models suggest some effects of climate change

  17. Modeling behavioral thermoregulation in a climate change sentinel.

    PubMed

    Moyer-Horner, Lucas; Mathewson, Paul D; Jones, Gavin M; Kearney, Michael R; Porter, Warren P

    2015-12-01

    When possible, many species will shift in elevation or latitude in response to rising temperatures. However, before such shifts occur, individuals will first tolerate environmental change and then modify their behavior to maintain heat balance. Behavioral thermoregulation allows animals a range of climatic tolerances and makes predicting geographic responses under future warming scenarios challenging. Because behavioral modification may reduce an individual's fecundity by, for example, limiting foraging time and thus caloric intake, we must consider the range of behavioral options available for thermoregulation to accurately predict climate change impacts on individual species. To date, few studies have identified mechanistic links between an organism's daily activities and the need to thermoregulate. We used a biophysical model, Niche Mapper, to mechanistically model microclimate conditions and thermoregulatory behavior for a temperature-sensitive mammal, the American pika (Ochotona princeps). Niche Mapper accurately simulated microclimate conditions, as well as empirical metabolic chamber data for a range of fur properties, animal sizes, and environmental parameters. Niche Mapper predicted pikas would be behaviorally constrained because of the need to thermoregulate during the hottest times of the day. We also showed that pikas at low elevations could receive energetic benefits by being smaller in size and maintaining summer pelage during longer stretches of the active season under a future warming scenario. We observed pika behavior for 288 h in Glacier National Park, Montana, and thermally characterized their rocky, montane environment. We found that pikas were most active when temperatures were cooler, and at sites characterized by high elevations and north-facing slopes. Pikas became significantly less active across a suite of behaviors in the field when temperatures surpassed 20°C, which supported a metabolic threshold predicted by Niche Mapper. In general

  18. Testing alternative models of climate-mediated extirpations

    USGS Publications Warehouse

    Beever, E.A.; Chris, R.A.Y.; Mote, P.W.; Wilkening, J.L.

    2010-01-01

    Biotic responses to climate change will vary among taxa and across latitudes, elevational gradients, and degrees of insularity. However, due to factors such as phenotypic plasticity, ecotypic variation, and evolved tolerance to thermal stress, it remains poorly understood whether losses should be greatest in populations experiencing the greatest climatic change or living in places where the prevailing climate is closest to the edge of the species' bioclimatic envelope (e.g., at the hottest, driest sites). Research on American pikas (Ochotona princeps) in montane areas of the Great Basin during 1994-1999 suggested that 20th-century population extirpations were predicted by a combination of biogeographic, anthropogenic, and especially climatic factors. Surveys during 2005-2007 documented additional extirpations and within-site shifts of pika distributions at remaining sites. To evaluate the evidence in support of alternative hypotheses involving effects of thermal stress on pikas, we placed temperature sensors at 156 locations within pika habitats in the vicinity of 25 sites with historical records of pikas in the Basin. We related these time series of sensor data to data on ambient temperature from weather stations within the Historical Climate Network. We then used these highly correlated relationships, combined with long-term data from the same weather stations, to hindcast temperatures within pika habitats from 1945 through 2006. To explain patterns of loss, we posited three alternative classes of direct thermal stress: (1) acute cold stress (number of days below a threshold temperature); (2) acute heat stress (number of days above a threshold, temperature); and. (3) chronic heat stress (average summer temperature). Climate change was defined as change in our thermal metrics between two 31-y.r periods: 1945-1975 and 1976-2006. We found that patterns of persistence were well predicted by metrics of climate. Our best models suggest some effects of climate change

  19. In vitro and in vivo immunostimulatory effects of hot water extracts from the leaves of Artemisia princeps Pampanini cv. Sajabal.

    PubMed

    Kim, Tae-Hee; Lee, Seung-Jun; Rim, Hong-Kun; Shin, Ji-Sun; Jung, Ji-Yun; Heo, Jin-Sun; Kim, Jong-Bok; Lee, Myung-Suk; Lee, Kyung-Tae

    2013-08-26

    Artemisia princeps Pampanini (Asteraceae) is used as a traditional medicine to immune function-related diseases, such as dysmenorrhea, inflammation, cancer, and ulcers. The purpose of this study is to evaluate the immunostimulatory effects of the hot water extract from the leaves of Artemisia princeps Pampanini (WAPP) in recombinant interferon-γ (rIFN-γ)-primed RAW 264.7 macrophages and in cyclophosphamide (20mg/kg, i.p.)-induced immunosuppressed Sprague-Dawley rats. RAW 264.7 macrophages were treated with WAPP and production and expressions of nitric oxide (NO) and tumor necrosis factor-α (TNF-α) via nuclear factor-κB (NF-κB) were detected by immunoassay, western blot, qRT-PCR and reporter gene assay. In addition, in vivo immunomodulatory activity was studied by cyclophosphamide-induced myelosuppression in rats. In rIFN-γ-primed RAW 264.7 macrophages, pretreatment with WAPP increased the productions of nitric oxide (NO) and tumor necrosis factor-α (TNF-α),and increased the expressions of inducible nitric oxide synthase (iNOS) at the protein level and of iNOS and TNF-α at the mRNA level. Molecular data revealed that WAPP upregulated the transcriptional activity and translocation of nuclear factor-κB (NF-κB) by activating inhibitory kappa B-α (IκB-α) degradation and phosphorylation. Furthermore, WAPP upregulated the phosphorylations of p38 MAP kinase, c-Jun NH2-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK1/2). In cycloheximide-induced immunosuppressed rats, pretreatment with WAPP (100, 200, or 400mg/kg, p.o.) increased the serum levels of albumin and globulin, and reduced immobility times. Our results suggest that upregulations of the expressions of iNOS and TNF-α via the activations of NF-κB and MAPK are responsible for the immunostimulatory effects of WAPP. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Long-term Treatment with Oriental Medicinal Herb Artemisia princeps Alters Neuroplasticity in a Rat Model of Ovarian Hormone Deficiency

    PubMed Central

    Kim, Hyun-Bum; Kwon, Byeong-Jae; Cho, Hyun-Ji; Kim, Ji-Won; Chon, Jeong-Woo; Do, Moon-Ho; Park, Sang-Yong; Kim, Sun-Yeou; Maeng, Sung-Ho; Park, Yoo-Kyoung

    2015-01-01

    Artemisia princeps (AP) is a flowering perennial used as a traditional medicine and dietary supplement across East Asia. No study has yet assessed its effects on synaptic plasticity in hippocampus and much less in a model of ovarian hormone deficiency. We examined the influence of chronic oral AP ethanol extract treatment in ovariectomized rats on the induction of long-term depression in a representative synapse (CA3-CA1) of the hippocampus. Ovariectomized rats demonstrated lower trabecular mean bone mineral densities than sham, validating the establishment of pathology. Against this background of pathology, AP-treated ovariectomized rats exhibited attenuated long-term depression (LTD) in CA1 relative to water-treated controls as measured by increased field excitatory post-synaptic potentials (fEPSP) activation averages over the post-stimulation period. While pathological significance of long-term depression (LTD) in ovariectomized rats is conflicting, that AP treatment significantly affected its induction offers justification for further study of its influences on plasticity and its related disorders. PMID:25792871

  1. A New Member of Gamma-Conotoxin Family Isolated from Conus princeps Displays a Novel Molecular Target

    PubMed Central

    Bernáldez, Johanna; Jiménez, Samanta; González, Luis Javier; Ferro, Jesús Noda; Soto, Enrique; Salceda, Emilio; Chávez, Daniela; Aguilar, Manuel B.; Licea-Navarro, Alexei

    2016-01-01

    A novel conotoxin, named as PiVIIA, was isolated from the venom of Conus princeps, a marine predatory cone snail collected in the Pacific Southern Coast of Mexico. Chymotryptic digest of the S-alkylated peptide in combination with liquid chromatography coupled to tandem mass spectrometry, were used to define the sequencing of this peptide. Eleven N-terminal amino acids were verified by automated Edman degradation. PiVIIA is a 25-mer peptide (CDAOTHYCTNYWγCCSGYCγHSHCW) with six cysteine residues forming three disulphide bonds, a hydroxyproline (O) and two gamma carboxyglutamic acid (γ) residues. Based on the arrangement of six Cys residues (C-C-CC-C-C), this conotoxin might belong to the O2-superfamily. Moreover, PiVIIA has a conserved motif (-γCCS-) that characterizes γ-conotoxins from molluscivorous Conus. Peptide PiVIIA has 45% sequence identity with γ-PnVIIA—the prototype of this family. Biological activity of PiVIIA was assessed by voltage-clamp recording in rat dorsal root ganglion neurons. Perfusion of PiVIIA in the µM range produces a significant increase in the Ca2+ currents, without significantly modifying the Na+, K+ or proton-gated acid sensing ionic currents. These results indicate that PiVIIA is a new conotoxin whose activity deserves further studies to define its potential use as a positive modulator of neuronal activity. PMID:26861393

  2. A New Member of Gamma-Conotoxin Family Isolated from Conus princeps Displays a Novel Molecular Target.

    PubMed

    Bernáldez, Johanna; Jiménez, Samanta; González, Luis Javier; Ferro, Jesús Noda; Soto, Enrique; Salceda, Emilio; Chávez, Daniela; Aguilar, Manuel B; Licea-Navarro, Alexei

    2016-02-05

    A novel conotoxin, named as PiVIIA, was isolated from the venom of Conus princeps, a marine predatory cone snail collected in the Pacific Southern Coast of Mexico. Chymotryptic digest of the S-alkylated peptide in combination with liquid chromatography coupled to tandem mass spectrometry, were used to define the sequencing of this peptide. Eleven N-terminal amino acids were verified by automated Edman degradation. PiVIIA is a 25-mer peptide (CDAOTHYCTNYWγCCSGYCγHSHCW) with six cysteine residues forming three disulphide bonds, a hydroxyproline (O) and two gamma carboxyglutamic acid (γ) residues. Based on the arrangement of six Cys residues (C-C-CC-C-C), this conotoxin might belong to the O2-superfamily. Moreover, PiVIIA has a conserved motif (-γCCS-) that characterizes γ-conotoxins from molluscivorous Conus. Peptide PiVIIA has 45% sequence identity with γ-PnVIIA-the prototype of this family. Biological activity of PiVIIA was assessed by voltage-clamp recording in rat dorsal root ganglion neurons. Perfusion of PiVIIA in the µM range produces a significant increase in the Ca(2+) currents, without significantly modifying the Na⁺, K⁺ or proton-gated acid sensing ionic currents. These results indicate that PiVIIA is a new conotoxin whose activity deserves further studies to define its potential use as a positive modulator of neuronal activity.

  3. Epistasis Constrains Mutational Pathways of Hemoglobin Adaptation in High-Altitude Pikas

    PubMed Central

    Tufts, Danielle M.; Natarajan, Chandrasekhar; Revsbech, Inge G.; Projecto-Garcia, Joana; Hoffmann, Federico G.; Weber, Roy E.; Fago, Angela; Moriyama, Hideaki; Storz, Jay F.

    2015-01-01

    A fundamental question in evolutionary genetics concerns the roles of mutational pleiotropy and epistasis in shaping trajectories of protein evolution. This question can be addressed most directly by using site-directed mutagenesis to explore the mutational landscape of protein function in experimentally defined regions of sequence space. Here, we evaluate how pleiotropic trade-offs and epistatic interactions influence the accessibility of alternative mutational pathways during the adaptive evolution of hemoglobin (Hb) function in high-altitude pikas (Mammalia: Lagomorpha). By combining ancestral protein resurrection with a combinatorial protein-engineering approach, we examined the functional effects of sequential mutational steps in all possible pathways that produced an increased Hb–O2 affinity. These experiments revealed that the effects of mutations on Hb–O2 affinity are highly dependent on the temporal order in which they occur: Each of three β-chain substitutions produced a significant increase in Hb–O2 affinity on the ancestral genetic background, but two of these substitutions produced opposite effects when they occurred as later steps in the pathway. The experiments revealed pervasive epistasis for Hb–O2 affinity, but affinity-altering mutations produced no significant pleiotropic trade-offs. These results provide insights into the properties of adaptive substitutions in naturally evolved proteins and suggest that the accessibility of alternative mutational pathways may be more strongly constrained by sign epistasis for positively selected biochemical phenotypes than by antagonistic pleiotropy. PMID:25415962

  4. Adaptive divergence along environmental gradients in a climate-change-sensitive mammal.

    PubMed

    Henry, P; Russello, M A

    2013-10-01

    In the face of predicted climate change, a broader understanding of biotic responses to varying environments has become increasingly important within the context of biodiversity conservation. Local adaptation is one potential option, yet remarkably few studies have harnessed genomic tools to evaluate the efficacy of this response within natural populations. Here, we show evidence of selection driving divergence of a climate-change-sensitive mammal, the American pika (Ochotona princeps), distributed along elevation gradients at its northern range margin in the Coast Mountains of British Columbia (BC), Canada. We employed amplified-fragment-length-polymorphism-based genomic scans to conduct genomewide searches for candidate loci among populations inhabiting varying environments from sea level to 1500 m. Using several independent approaches to outlier locus detection, we identified 68 candidate loci putatively under selection (out of a total 1509 screened), 15 of which displayed significant associations with environmental variables including annual precipitation and maximum summer temperature. These candidate loci may represent important targets for predicting pika responses to climate change and informing novel approaches to wildlife conservation in a changing world.

  5. Limb bone morphology, bone strength, and cursoriality in lagomorphs

    PubMed Central

    Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

    2014-01-01

    The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which ‘cursorial specialization’ affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and μCT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high ‘displacement advantage’, permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with

  6. Dose-response study of sajabalssuk ethanol extract from Artemisia princeps Pampanini on blood glucose in subjects with impaired fasting glucose or mild type 2 diabetes.

    PubMed

    Choi, Ji-Young; Shin, Su-Kyung; Jeon, Seon-Min; Baek, Nam-In; Chung, Hae-Gon; Jeong, Tae-Sook; Lee, Kyung Tae; Lee, Mi-Kyung; Choi, Myung-Sook

    2011-01-01

    Previously we reported that an ethanol extract from Artemisia princeps Pampanini lowered blood glucose in db/db mice. Here we report a preliminary study in which the blood glucose-lowering effects of two different doses of sajabalssuk ethanol extract (SBE), containing eupatilin and jaseocidin, were examined in hyperglycemic subjects with fasting blood glucose (FBG) levels of 100-150 mg/dL. Subjects were randomized into four groups: negative control (2,000 mg of lactose /day), positive control (1,140 mg of pinitol/day), low-dose SBE (2,000 mg of SBE/day), and high-dose SBE (4,000 mg of SBE/day). After 8 weeks of supplementation, FBG and glycosylated hemoglobin levels were significantly lowered in low-and high-dose SBE groups compared to the baseline values; high-dose SBE also resulted in significantly lower plasma free fatty acid levels and systolic blood pressure. This study demonstrated that supplementation of 2 g or 4 g of SBE daily can significantly reduce blood glucose in hyperglycemic subjects, although high-dose SBE seemed to be more effective than low-dose SBE for lowering plasma free fatty acid level and systolic blood pressure.

  7. The effect of essential oils of dietary wormwood (Artemisia princeps), with and without added vitamin E, on oxidative stress and some genes involved in cholesterol metabolism.

    PubMed

    Chung, Mi Ja; Kang, Ah-Young; Park, Sung-Ok; Park, Kuen-Woo; Jun, Hee-Jin; Lee, Sung-Joon

    2007-08-01

    Wormwood (Artemisia princeps) due to the abundance of antioxidant in its essential oils (EO), has been used as a traditional drug and health food in Korea. Oxidative stress plays an important role in the etiology of atherosclerosis thus antioxidative chemicals improves hepatic lipid metabolism partly by reducing oxysterol formation. The antioxidant activity was assessed using two methods, human low-density lipoprotein (LDL) oxidation and the anti-DPPH free radical assays. It was found that the antioxidant activity of EO with vitamin E higher than EO alone. To study mechanisms accounting for the antiatherosclerotic properties of this wormwood EO, we examined the expression of key genes in cholesterol metabolism such as the LDL receptor, the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and sterol regulatory element binding proteins. The induction was increased up to twofold at 0.05 mg/mL of EO treatment in HepG2 cells for 24h. When EO (0.2 mg/mL) was co-incubated with vitamin E, interestingly, the LDL receptor was dramatically induced by 5-6-folds. HMG-CoA reductase did not change. However, treatment with the higher concentration resulted in cytotoxicity. Our data suggest that wormwood EO with vitamin E may be anti-atherogenic due to their inhibition of LDL oxidation and upregulation of the LDL receptor.

  8. Adaptation of a Gaussia princeps Luciferase reporter system in Candida albicans for in vivo detection in the Galleria mellonella infection model.

    PubMed

    Delarze, Eric; Ischer, Françoise; Sanglard, Dominique; Coste, Alix T

    2015-01-01

    For the past 10 years, mini-host models and in particular the greater wax moth Galleria mellonella have tended to become a surrogate for murine models of fungal infection mainly due to cost, ethical constraints and ease of use. Thus, methods to better assess the fungal pathogenesis in G. mellonella need to be developed. In this study, we implemented the detection of Candida albicans cells expressing the Gaussia princeps luciferase in its cell wall in infected larvae of G. mellonella. We demonstrated that detection and quantification of luminescence in the pulp of infected larvae is a reliable method to perform drug efficacy and C. albicans virulence assays as compared to fungal burden assay. Since the linearity of the bioluminescent signal, as compared to the CFU counts, has a correlation of R(2) = 0.62 and that this method is twice faster and less labor intensive than classical fungal burden assays, it could be applied to large scale studies. We next visualized and followed C. albicans infection in living G. mellonella larvae using a non-toxic and water-soluble coelenterazine formulation and a CCD camera that is commonly used for chemoluminescence signal detection. This work allowed us to follow for the first time C. albicans course of infection in G. mellonella during 4 days.

  9. A novel biorational pesticide: efficacy of methionine against Heraclides (Papilio) cresphontes, a surrogate of the invasive Princeps (Papilio) demoleus (Lepidoptera: Papilionidae).

    PubMed

    Lewis, Delano S; Cuda, James P; Stevens, Bruce R

    2011-12-01

    ABSTRACT The Southeast Asian citrus-feeding butterfly Princeps (Papilio) demoleus (L.) was recently introduced into the Americas, causing an imminent threat to citrus production and ornamental flora. The human nutrient amino acid methionine has been shown by us to disrupt aminoacid-modulated ion transport systems in caterpillars and other insect larvae that possess an alkaline midgut. Heraclides (Papilio) cresphontes was bioassayed as a United States Department of Agriculture permitted surrogate of the Florida quarantined P. demoleus to test the potential efficacy of methionine. Larvae were allowed to feed ad libitum on wild lime plants with leaves treated with methionine or proline. Methionine caused 100% mortality in first through fourth instars in a time- and dose-dependent manner, as determined by probit analysis whereas proline was not toxic. Wild lime host plants did not exhibit phytotoxicity with methionine treatments during a 14 d test period. It is concluded that methionine is an effective larvicide against H. cresphontes, and therefore may be a candidate environmentally safe biorational pesticide for use against invasive P. demoleus in the Americas.

  10. Science Challenges in Supporting Adaptation Planning in Mountainous Terrain: Lessons from the NOAA climate assessment to inform the FWS Status Review of the American pika

    NASA Astrophysics Data System (ADS)

    Ray, A. J.; Barsugli, J. J.; Eischeid, J.; Wolter, K.

    2010-12-01

    This presentation will summarize results and some of the scientific challenges that were faced in preparing a NOAA rapid assessment of climate provided as input to the Fish & Wildlife Service review of the American Pika to determine if climate change risks warranted listing the species as endangered. NOAA provided FWS with an assessment of climate observations and projections of change in pika habitat, as a climatological context for the status review. We provided western regional detail based on existing observations and IPCC model projections and new findings from interpreting those observations and projections at smaller spatial scales. A key finding of the report is the large spatial scale of recent and projected warming trends in the West. The 2050 summer temperature projections average about 3°C higher than recent climatology for most of the western U.S., and for 22 locations representative of pika habitats. Statistically downscaled temperature projections were used to relate these large-scale trends to habitat elevation bands. Finally, we provided an expert judgment on the “foreseeable future” for climate for the review. This project required considering the observations and projections in the context of the heterogeneous terrain that is the habitat for many pika populations, and interpreting and interpolating information from often distant observing stations, or large-scale model grid-boxes to make inferences about conditions at finer scales. This presentation will discuss the findings of the report, and some of the strategies that we adopted for analyzing and presenting climate projections. The emphasis will be on this real-world example where time and resource constraints were paramount, as well as the need to use “best available science,” in the context of a formal policy process vs. time to develop new work. Some of the challenges we faced are applicable to many ecological applications and for many individual species, including the choice of

  11. Effect of dietary supplementation of Lactobacillus-fermented Artemisia princeps on growth performance, meat lipid peroxidation, and intestinal microflora in Hy-line Brown male chickens.

    PubMed

    Kim, C H; Kim, G-B; Chang, M B; Bae, G S; Paik, I K; Kil, D Y

    2012-11-01

    The objective of this experiment was to investigate the effect of dietary supplementation of Lactobacillus-fermented Artemisia princeps (LFA) on growth performance, meat lipid peroxidation, and intestinal microflora in Hy-line Brown male chickens. A total of six hundred twenty-four 1-d-old Hy-Line Brown male chicks were randomly allotted to 3 dietary treatments with 4 replicated pens consisting of 52 chicks. The control diet was formulated to be adequate in energy and nutrients. Two additional diets were prepared by adding 2.5 or 5.0 g/kg of LFA to the control diet. The experimental diets were fed on an ad libitum basis to the birds during 7 wk. Body weight gain and feed intake were recorded at 2 and 7 wk. At the end of the experiment, 2 birds from each treatment were killed by cervical dislocation and the samples for ileal content, breast, and thigh meat were collected for the determination of meat lipid peroxidation and microbial population. Results indicated that increasing inclusion level of LFA in diets improved BW gain (linear and quadratic, P < 0.05) and tended to improve feed efficiency (linear and quadratic, P < 0.10) of birds during 0 to 7 wk. Feeding the diets containing increasing amounts of LFA to birds reduced (quadratic, P < 0.05) thiobarbituric acid-reactive substance (TBARS) values in breast and thigh meat during 15 d of storage. The concentrations of Lactobacillus spp. in the ileal content of birds increased (linear and quadratic, P < 0.05), but those of Salmonella spp. tended to be decreased (quadratic, P < 0.10) as inclusion level of LFA in diets increased. These results suggest that dietary LFA may be used as a functional ingredient to improve growth performance, meat lipid stability, and intestinal health of birds.

  12. The Late Quaternary biogeographic histories of some Great Basin mammals (western USA)

    NASA Astrophysics Data System (ADS)

    Grayson, Donald K.

    2006-11-01

    The Great Basin of arid western North America provides one of the most detailed late Pleistocene and Holocene mammal records available for any part of the world, though the record is by far strongest for small mammals. Of the 35 genera of now-extinct North American Pleistocene mammals, 19 are known to have occurred in the Great Basin, a list that is likely to be complete or nearly so. Of these 19, seven can be shown to have survived beyond 12,000 radiocarbon years ago, a proportion similar to that for North America as a whole. Horses, camels, mammoth, and helmeted musk-oxen appear to have been the most abundant of these genera. Pygmy rabbits ( Brachylagus idahoensis), yellow-bellied marmots ( Marmota flaviventris), and bushy-tailed woodrats ( Neotoma cinerea) declined in abundance at the end of the Pleistocene, at about the same time as populations south of their current arid western distributional boundary were extirpated. Subsequent declines occurred during the hot/dry middle Holocene. Pygmy rabbits also declined as modern pinyon-juniper woodlands developed across the Great Basin. The Snake Range of eastern Nevada has seen the late Pleistocene or Holocene extinction of both northern pocket gophers ( Thomomys talpoides) and pikas ( Ochotona princeps). Coupled with the rarity of yellow-bellied marmots here, these histories make the Snake Range a biogeographic oddity. These and other Great Basin mammal histories provide significant insights into the possible responses of Great Basin small mammals to global warming.

  13. From promise to practice: pairing non-invasive sampling with genomics in conservation.

    PubMed

    Russello, Michael A; Waterhouse, Matthew D; Etter, Paul D; Johnson, Eric A

    2015-01-01

    Conservation genomics has become an increasingly popular term, yet it remains unclear whether the non-invasive sampling that is essential for many conservation-related studies is compatible with the minimum requirements for harnessing next-generation sequencing technologies. Here, we evaluated the feasibility of using genotyping-by-sequencing of non-invasively collected hair samples to simultaneously identify and genotype single nucleotide polymorphisms (SNPs) in a climate-sensitive mammal, the American pika (Ochotona princeps). We identified and genotyped 3,803 high-confidence SNPs across eight sites distributed along two elevational transects using starting DNA amounts as low as 1 ng. Fifty-five outlier loci were detected as candidate gene regions under divergent selection, constituting potential targets for future validation. Genome-wide estimates of gene diversity significantly and positively correlated with elevation across both transects, with all low elevation sites exhibiting significant heterozygote deficit likely due to inbreeding. More broadly, our results highlight a range of issues that must be considered when pairing genomic data collection with non-invasive sampling, particularly related to field sampling protocols for minimizing exogenous DNA, data collection strategies and quality control steps for enhancing target organism yield, and analytical approaches for maximizing cost-effectiveness and information content of recovered genomic data.

  14. Late Quaternary environments and biogeography in the Great Basin

    NASA Astrophysics Data System (ADS)

    Thompson, R. S.; Mead, J. I.

    1982-01-01

    Plant and animal remains found in packrat ( Neotoma spp.) middens and cave fill from the eastern and southern Great Basin region reveal the presence of subalpine conifers and boreal mammals at relatively low elevations during the Late Wisconsin. Limber pine ( Pinus flexilis) and bristlecone pine ( P. longaeva) were important in the late Pleistocene plant communities throughout this region. Spruce ( Picea cf. engelmannii) and common juniper ( Juniperus communis) were present in some of the more northerly localities, and Douglas fir ( Pseudotsuga menziesii) and white fir ( Abies concolor) were present in southern and eastern localities. Single needle pinyon pine ( Pinus monophylla), common across this region today, was apparently not present north of the Sheep Range of southern Nevada during the Late Wisconsin. Pikas ( Ochotona cf. princeps), small boreal mammals present in only a few Great Basin mountain ranges today, were common throughout the region. Heather voles ( Phenacomys cf. intermedius) have been found in two cave fill deposits in Nevada, though they are unknown in the Great Basin today. Limber and bristlecone pines are generally restricted to rocky substrates in modern subalpine habitats in the Great Basin, and this may also have been the case when these plants grew at lower elevations during the Late Wisconsin. Subalpine conifers were present on the rock outcrops sampled by the packrat middens, but shrub communities, perhaps dominated by sagebrush ( Artemisia spp.), may have been present on alluvial valley-bottom substrates. Forested habitats would thus have been isolated habitat islands, as they are today. Boreal small mammals, including pikas and heather voles, were able to colonize the Great Basin mountain ranges during the late Pleistocene. We suggest that these mammals were able to survive in the intervening valley-bottoms under a cool-summer climatic regime, and that continuous forest or woodland corridors were not necessary for migration.

  15. LaGomiCs—Lagomorph Genomics Consortium: An International Collaborative Effort for Sequencing the Genomes of an Entire Mammalian Order

    PubMed Central

    Di Palma, Federica; Flicek, Paul; Smith, Andrew T.; Thulin, Carl-Gustaf

    2016-01-01

    The order Lagomorpha comprises about 90 living species, divided in 2 families: the pikas (Family Ochotonidae), and the rabbits, hares, and jackrabbits (Family Leporidae). Lagomorphs are important economically and scientifically as major human food resources, valued game species, pests of agricultural significance, model laboratory animals, and key elements in food webs. A quarter of the lagomorph species are listed as threatened. They are native to all continents except Antarctica, and occur up to 5000 m above sea level, from the equator to the Arctic, spanning a wide range of environmental conditions. The order has notable taxonomic problems presenting significant difficulties for defining a species due to broad phenotypic variation, overlap of morphological characteristics, and relatively recent speciation events. At present, only the genomes of 2 species, the European rabbit (Oryctolagus cuniculus) and American pika (Ochotona princeps) have been sequenced and assembled. Starting from a paucity of genome information, the main scientific aim of the Lagomorph Genomics Consortium (LaGomiCs), born from a cooperative initiative of the European COST Action “A Collaborative European Network on Rabbit Genome Biology—RGB-Net” and the World Lagomorph Society (WLS), is to provide an international framework for the sequencing of the genome of all extant and selected extinct lagomorphs. Sequencing the genomes of an entire order will provide a large amount of information to address biological problems not only related to lagomorphs but also to all mammals. We present current and planned sequencing programs and outline the final objective of LaGomiCs possible through broad international collaboration. PMID:26921276

  16. LaGomiCs-Lagomorph Genomics Consortium: An International Collaborative Effort for Sequencing the Genomes of an Entire Mammalian Order.

    PubMed

    Fontanesi, Luca; Di Palma, Federica; Flicek, Paul; Smith, Andrew T; Thulin, Carl-Gustaf; Alves, Paulo C

    2016-07-01

    The order Lagomorpha comprises about 90 living species, divided in 2 families: the pikas (Family Ochotonidae), and the rabbits, hares, and jackrabbits (Family Leporidae). Lagomorphs are important economically and scientifically as major human food resources, valued game species, pests of agricultural significance, model laboratory animals, and key elements in food webs. A quarter of the lagomorph species are listed as threatened. They are native to all continents except Antarctica, and occur up to 5000 m above sea level, from the equator to the Arctic, spanning a wide range of environmental conditions. The order has notable taxonomic problems presenting significant difficulties for defining a species due to broad phenotypic variation, overlap of morphological characteristics, and relatively recent speciation events. At present, only the genomes of 2 species, the European rabbit (Oryctolagus cuniculus) and American pika (Ochotona princeps) have been sequenced and assembled. Starting from a paucity of genome information, the main scientific aim of the Lagomorph Genomics Consortium (LaGomiCs), born from a cooperative initiative of the European COST Action "A Collaborative European Network on Rabbit Genome Biology-RGB-Net" and the World Lagomorph Society (WLS), is to provide an international framework for the sequencing of the genome of all extant and selected extinct lagomorphs. Sequencing the genomes of an entire order will provide a large amount of information to address biological problems not only related to lagomorphs but also to all mammals. We present current and planned sequencing programs and outline the final objective of LaGomiCs possible through broad international collaboration. © The American Genetic Association. 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Evaluation of nutritional and economic feed values of spent coffee grounds and Artemisia princeps residues as a ruminant feed using in vitro ruminal fermentation.

    PubMed

    Seo, Jakyeom; Jung, Jae Keun; Seo, Seongwon

    2015-01-01

    Much research on animal feed has focused on finding alternative feed ingredients that can replace conventional ones (e.g., grains and beans) to reduce feed costs. The objective of this study was to evaluate the economic, as well as nutritional value of spent coffee grounds (SCG) and Japanese mugwort (Artemisia princeps) residues (APR) as alternative feed ingredients for ruminants. We also investigated whether pre-fermentation using Lactobacillus spp. was a feasible way to increase the feed value of these by-products. Chemical analyses and an in vitro study were conducted for SCG, APR, and their pre-fermented forms. All the experimental diets for in vitro ruminal fermentation were formulated to contain a similar composition of crude protein, neutral detergent fiber and total digestible nutrients at 1x maintenance feed intake based on the dairy National Research Council (NRC). The control diet was composed of ryegrass, corn, soybean meal, whereas the treatments consisted of SCG, SCG fermented with Lactobacillus spp. (FSCG), APR, and its fermented form (FAPR). The treatment diets replaced 100 g/kg dry matter (DM) of the feed ingredients in the control. Costs were lower for the all treatments, except FAPR, than that of the control. After 24-h incubation, the NDF digestibility of the diets containing SCG and its fermented form were significantly lower than those of the other diets (P < 0.01); pre-fermentation tended to increase NDF digestibility (P = 0.07), especially for APR. Supplementation of SCG significantly decreased total gas production (ml/g DM) after 24-h fermentation in comparison with the control (P < 0.05); however, there were no significant differences between the control and the SCG or the APR diets in total gas production, as expressed per Korean Won (KRW). Diets supplemented with SCG or FSCG tended to have a higher total volatile fatty acid (VFA) concentration, expressed as per KRW, compared with the control (P = 0.06). Conversely, the fermentation

  18. Evaluation of nutritional and economic feed values of spent coffee grounds and Artemisia princeps residues as a ruminant feed using in vitro ruminal fermentation

    PubMed Central

    Seo, Jakyeom; Jung, Jae Keun

    2015-01-01

    Much research on animal feed has focused on finding alternative feed ingredients that can replace conventional ones (e.g., grains and beans) to reduce feed costs. The objective of this study was to evaluate the economic, as well as nutritional value of spent coffee grounds (SCG) and Japanese mugwort (Artemisia princeps) residues (APR) as alternative feed ingredients for ruminants. We also investigated whether pre-fermentation using Lactobacillus spp. was a feasible way to increase the feed value of these by-products. Chemical analyses and an in vitro study were conducted for SCG, APR, and their pre-fermented forms. All the experimental diets for in vitro ruminal fermentation were formulated to contain a similar composition of crude protein, neutral detergent fiber and total digestible nutrients at 1x maintenance feed intake based on the dairy National Research Council (NRC). The control diet was composed of ryegrass, corn, soybean meal, whereas the treatments consisted of SCG, SCG fermented with Lactobacillus spp. (FSCG), APR, and its fermented form (FAPR). The treatment diets replaced 100 g/kg dry matter (DM) of the feed ingredients in the control. Costs were lower for the all treatments, except FAPR, than that of the control. After 24-h incubation, the NDF digestibility of the diets containing SCG and its fermented form were significantly lower than those of the other diets (P < 0.01); pre-fermentation tended to increase NDF digestibility (P = 0.07), especially for APR. Supplementation of SCG significantly decreased total gas production (ml/g DM) after 24-h fermentation in comparison with the control (P < 0.05); however, there were no significant differences between the control and the SCG or the APR diets in total gas production, as expressed per Korean Won (KRW). Diets supplemented with SCG or FSCG tended to have a higher total volatile fatty acid (VFA) concentration, expressed as per KRW, compared with the control (P = 0.06). Conversely, the fermentation

  19. Diversity of A-conotoxins of three worm-hunting cone snails (Conus brunneus, Conus nux, and Conus princeps) from the Mexican Pacific coast.

    PubMed

    Morales-González, Daniel; Flores-Martínez, Ernesto; Zamora-Bustillos, Roberto; Rivera-Reyes, Reginaldo; Michel-Morfín, Jesús Emilio; Landa-Jaime, Víctor; Falcón, Andrés; Aguilar, Manuel B

    2015-06-01

    Conus marine snails (∼500 species) are tropical predators that use venoms mainly to capture prey and defend themselves from predators. The principal components of these venoms are peptides that are known as "conotoxins" and generally comprise 7-40 amino acid residues, including 0-5 disulfide bridges and distinct posttranslational modifications. The most common molecular targets of conotoxins are voltage- and ligand-gated ion channels, G protein-coupled receptors, and neurotransmitter transporters, to which they bind, typically, with high affinity and specificity. Due to these properties, several conotoxins have become molecular probes, medicines, and leads for drug design. Conotoxins have been classified into genetic superfamilies based on the signal sequence of their precursors, and into pharmacological families according to their molecular targets. The objective of this work was to identify and analyze partial cDNAs encoding conotoxin precursors belonging to the A superfamily from Conus brunneus, Conus nux, and Conus princeps. These are vermivorous species of the Mexican Pacific coast from which only one A-conotoxin, and few O- and I2-conotoxins have been reported. Employing RT-PCR, we identified 30 distinct precursors that contain 13 different predicted mature toxins. With the exception of two groups of four highly similar peptides, these toxins are diverse at both the sequence and the physicochemical levels, and they belong to the 4/3, 4/4, 4/5, 4/6, and 4/7 structural subfamilies. These toxins are predicted to target diverse nicotinic acetylcholine receptor (nAChR) subtypes: nx1d, muscle; pi1a-pi1d, α3β2, α7, and/or α9α10; br1a, muscle, α3β4, and/or α4β2; and nx1a-nx1c/pi1g and pi1h, α3β2, α3β4, α9β10, and/or α7. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Identification, by RT-PCR, of eight novel I₂-conotoxins from the worm-hunting cone snails Conus brunneus, Conus nux, and Conus princeps from the eastern Pacific (Mexico).

    PubMed

    Zamora-Bustillos, R; Rivera-Reyes, R; Aguilar, M B; Michel-Morfín, E; Landa-Jaime, V; Falcón, A; Heimer, E P

    2014-03-01

    Marine snails of the genus Conus (∼500 species) are tropical predators that produce venoms for capturing prey, defense and competitive interactions. These venoms contain 50-200 different peptides ("conotoxins") that generally comprise 7-40 amino acid residues (including 0-5 disulfide bridges), and that frequently contain diverse posttranslational modifications, some of which have been demonstrated to be important for folding, stability, and biological activity. Most conotoxins affect voltage- and ligand-gated ion channels, G protein-coupled receptors, and neurotransmitter transporters, generally with high affinity and specificity. Due to these features, several conotoxins are used as molecular tools, diagnostic agents, medicines, and models for drug design. Based on the signal sequence of their precursors, conotoxins have been classified into genetic superfamilies, whereas their molecular targets allow them to be classified into pharmacological families. The objective of this work was to identify and analyze partial cDNAs encoding precursors of conotoxins belonging to I superfamily from three vermivorous species of the Mexican Pacific coast: C. brunneus, C. nux and C. princeps. The precursors identified contain diverse numbers of amino acid residues (C. brunneus, 65 or 71; C. nux, 70; C. princeps, 72 or 73), and all include a highly conserved signal peptide, a C-terminal propeptide, and a mature toxin. All the latter have one of the typical Cys frameworks of the I-conotoxins (C-C-CC-CC-C-C). The prepropeptides belong to the I2-superfamily, and encode eight different hydrophilic and acidic mature toxins, rather similar among them, and some of which have similarity with I2-conotoxins targeting voltage- and voltage-and-calcium-gated potassium channels.

  1. First description of the nymph and larva of Dermacentor raskemensis (Acari: Ixodidae), parasites of pikas and other small mammals in Central Asia.

    PubMed

    Apanaskevich, Dmitry A

    2013-09-01

    Dermacentor raskemensis Pomerantzev, 1946 is one of the rare Asian species in this genus. The immature stages of this species have never been described. Reexamination of D. raskemensis holdings stored in the United States National Tick Collection revealed a collection lot containing reared nymphs and larvae of this species. This collection made it possible for us to find numerous nymphs and larvae of D. raskemensis among previously unidentified material collected in the field. Both immature stages of D. raskemensis are described here for the first time. Nymphs of D. raskemensis can be distinguished from those of other Dermacentor species in the region by small spiracular plate, relatively short and obtuse lateral projections of basis capituli dorsally, relatively short spurs on coxa I and the internal spur is characteristically very broadly rounded at its apex, and very small spur on coxa IV, whereas larvae of D. raskemensis can be distinguished from other Dermacentor by relatively short and obtuse lateral projections of basis capituli, approximately 6 denticles in the median files on hypostome, and relatively short, broad, and rounded spur on coxa I. The nymphs and larvae of D. raskemensis studied originate from Afghanistan, India, Iran, and Pakistan, where they were collected from pikas and other small mammals.

  2. First Description of the Nymph and Larva of Dermacentor raskemensis (Acari: Ixodidae), Parasites of Pikas and Other Small Mammals in Central Asia

    PubMed Central

    Apanaskevich, Dmitry A.

    2014-01-01

    Dermacentor raskemensis Pomerantzev, 1946 is one of the rare Asian species in this genus. The immature stages of this species have never been described. Reexamination of D. raskemensis holdings stored in the United States National Tick Collection revealed a collection lot containing reared nymphs and larvae of this species. This collection made it possible for us to find numerous nymphs and larvae of D. raskemensis among previously unidentified material collected in the field. Both immature stages of D. raskemensis are described here for the first time. Nymphs of D. raskemensis can be distinguished from those of other Dermacentor species in the region by small spiracular plate, relatively short and obtuse lateral projections of basis capituli dorsally, relatively short spurs on coxa I and the internal spur is characteristically very broadly rounded at its apex, and very small spur on coxa IV, whereas larvae of D. raskemensis can be distinguished from other Dermacentor by relatively short and obtuse lateral projections of basis capituli, ≈6 denticles in the median files on hypostome, and relatively short, broad, and rounded spur on coxa I. The nymphs and larvae of D. raskemensis studied originate from Afghanistan, India, Iran, and Pakistan, where they were collected from pikas and other small mammals. PMID:24180099

  3. Artemisia princeps Pamp. Essential oil and its constituents eucalyptol and α-terpineol ameliorate bacterial vaginosis and vulvovaginal candidiasis in mice by inhibiting bacterial growth and NF-κB activation.

    PubMed

    Trinh, Hien-Trung; Lee, In-Ah; Hyun, Yang-Jin; Kim, Dong-Hyun

    2011-12-01

    To investigate the inhibitory effects of Artemisia princeps Pamp. (family Asteraceae) essential oil (APEO) and its main constituents against bacterial vaginosis and vulvovaginal candidiasis, their antimicrobial activities against Gardnerella vaginalis and Candida albicans in vitro and their anti-inflammatory effects against G. vaginalis-induced vaginosis and vulvovaginal candidiasis were examined in mice. APEO and its constituents eucalyptol and α-terpineol were found to inhibit microbe growths. α-Terpineol most potently inhibited the growths of G. vaginalis and C. albicans with MIC values of 0.06 and 0.125 % (v/v), respectively. The antimicrobial activity of α-terpineol was found to be comparable to that of clotrimazole. Intravaginal treatment with APEO, eucalyptol, or α-terpineol significantly decreased viable G. vaginalis and C. albicans numbers in the vaginal cavity and myeloperoxidase activity in mouse vaginal tissues compared with controls. These agents also inhibited the expressions of proinflammatory cytokines (IL-1 β, IL-6, TNF- α), COX-2, iNOS, and the activation of NF- κB and increased expression of the anti-inflammatory cytokine IL-10. In addition, they inhibited the expressions of proinflammatory cytokines and the activation of NF- κB in lipopolysaccharide-stimulated peritoneal macrophages, and α-terpineol most potently inhibited the expressions of proinflammatory cytokines and NF- κB activation. Based on these findings, APEO and its constituents, particularly α-terpineol, ameliorate bacterial vaginosis and vulvovaginal candidiasis by inhibiting the growths of vaginal pathogens and the activation of NF- κB.

  4. Adapting to climate change at Glacier National Park, Montana, USA (Invited)

    NASA Astrophysics Data System (ADS)

    Fagre, D. B.

    2009-12-01

    The impact of climate change on mountain watersheds has been studied at Glacier National Park, Montana since 1991. Despite a 14% increase in annual precipitation, glaciers have receded, snow packs have diminished, and late season stream discharge has declined. Snow melts one month earlier in the spring, leading to earlier hydrologic peaks and tree invasions of subalpine meadows. This has been largely driven by annual temperature increases that are 2-3 times greater than the global average for the past century. How do scientists and park managers adapt? Although stopping the glaciers from disappearing is not a management option, park staff have embarked on an aggressive education and interpretation effort to use melting glaciers as the segue into dialog about climate change. Media such as podcasts, handouts, posters, visitor center displays and roadside signage complement interpretive ranger-led talks about climate change and incorporate the latest glacial data from ongoing research. With few historic data on most animal populations, Glacier Park staff and other scientists are unable to assess the impacts of climate change to resources that the public cares about. They have recently initiated alpine wildlife monitoring programs to track populations of potentially climate-sensitive organisms such as the American pika (Ochotona princeps). Recognizing that climate change increases the frequency and severity of extreme weather events, design specifications for reconstruction of an alpine highway were adjusted to include larger culverts and hardened rock walls. Species that are dependent on cold water will be at risk as glaciers and snowfields disappear but managers cannot control these processes. However, they are proactively reducing other stressors to sensitive native fish species by removing exotic, introduced species that are competitors. In addition to these adaptation measures, Glacier Park has implemented shuttles, fleet conversions and enhanced building

  5. The importance of biologically relevant microclimates in habitat suitability assessments.

    PubMed

    Varner, Johanna; Dearing, M Denise

    2014-01-01

    Predicting habitat suitability under climate change is vital to conserving biodiversity. However, current species distribution models rely on coarse scale climate data, whereas fine scale microclimate data may be necessary to assess habitat suitability and generate predictive models. Here, we evaluate disparities between temperature data at the coarse scale from weather stations versus fine-scale data measured in microhabitats required for a climate-sensitive mammal, the American pika (Ochotona princeps). We collected two years of temperature data in occupied talus habitats predicted to be suitable (high elevation) and unsuitable (low elevation) by the bioclimatic envelope approach. At low elevations, talus surface and interstitial microclimates drastically differed from ambient temperatures measured on-site and at a nearby weather station. Interstitial talus temperatures were frequently decoupled from high ambient temperatures, resulting in instantaneous disparities of over 30 °C between these two measurements. Microhabitat temperatures were also highly heterogeneous, such that temperature measurements within the same patch of talus were not more correlated than measurements at distant patches. An experimental manipulation revealed that vegetation cover may cool the talus surface by up to 10 °C during the summer, which may contribute to this spatial heterogeneity. Finally, low elevation microclimates were milder and less variable than typical alpine habitat, suggesting that, counter to species distribution model predictions, these seemingly unsuitable habitats may actually be better refugia for this species under climate change. These results highlight the importance of fine-scale microhabitat data in habitat assessments and underscore the notion that some critical refugia may be counterintuitive.

  6. The Importance of Biologically Relevant Microclimates in Habitat Suitability Assessments

    PubMed Central

    Varner, Johanna; Dearing, M. Denise

    2014-01-01

    Predicting habitat suitability under climate change is vital to conserving biodiversity. However, current species distribution models rely on coarse scale climate data, whereas fine scale microclimate data may be necessary to assess habitat suitability and generate predictive models. Here, we evaluate disparities between temperature data at the coarse scale from weather stations versus fine-scale data measured in microhabitats required for a climate-sensitive mammal, the American pika (Ochotona princeps). We collected two years of temperature data in occupied talus habitats predicted to be suitable (high elevation) and unsuitable (low elevation) by the bioclimatic envelope approach. At low elevations, talus surface and interstitial microclimates drastically differed from ambient temperatures measured on-site and at a nearby weather station. Interstitial talus temperatures were frequently decoupled from high ambient temperatures, resulting in instantaneous disparities of over 30°C between these two measurements. Microhabitat temperatures were also highly heterogeneous, such that temperature measurements within the same patch of talus were not more correlated than measurements at distant patches. An experimental manipulation revealed that vegetation cover may cool the talus surface by up to 10°C during the summer, which may contribute to this spatial heterogeneity. Finally, low elevation microclimates were milder and less variable than typical alpine habitat, suggesting that, counter to species distribution model predictions, these seemingly unsuitable habitats may actually be better refugia for this species under climate change. These results highlight the importance of fine-scale microhabitat data in habitat assessments and underscore the notion that some critical refugia may be counterintuitive. PMID:25115894

  7. Sierra Nevada Rock Glaciers: Biodiversity Refugia in a Warming World?

    NASA Astrophysics Data System (ADS)

    Millar, C. I.; Westfall, R. D.

    2007-12-01

    also mapped 125 discrete locations of American pika (Ochotona princeps) and found a strong association of pika presence with active and relict RIFs, in particular cirque rock glaciers, valley rock glaciers, and boulder streams. Using the PRISM climate model and a small network of temperature dataloggers from RIF habitats, we present a climate envelope for the pika habitats we surveyed. We propose that the large area of RIFs in the Sierra Nevada over a range of elevations could provide extensive habitat for pika in the warming future. RIFs in general are a group of landforms little studied in high mountains of western North America but of potential increasing importance to hydrologic and ecologic function as climate warms in the future. Millar, C.I. and R.D. Westfall. In press. Rock glaciers and periglacial rock-ice features in the Sierra Nevada; Classification, distribution, and climate relationships. Quaternary International.

  8. Testis-specific lactate dehydrogenase is expressed in somatic tissues of plateau pikas☆

    PubMed Central

    Wang, Duowei; Wei, Lian; Wei, Dengbang; Rao, Xinfeng; Qi, Xinzhang; Wang, Xiaojun; Ma, Benyuan

    2013-01-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the interconversion of pyruvate with lactate. In mammals the, Ldh-c gene was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), belonging to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living at 3000–5000 m above sea levelon the Qinghai-Tibet Plateau. We found that the expression pattern of six LDH isoenzymes in the somatic tissues of female and male plateau pikas to be the same as those in testis and sperm, suggesting that LDH-C4 was expressed in somatic tissues of plateau pika. Here we report the detection of LDHC in the somatic tissues of plateau pika using RT-PCR, Western blotting and immunohistochemistry. Our results indicate that Ldh-c mRNA is transcribed in the heart, liver, lung, kidney, brain, skeletal muscle and testis. In somatic tissues LDHC was translated in the cytoplasm, while in testis it was expressed in both cytoplasm and mitochondria. The third band from cathode to anode in LDH isoenzymes was identified as LDH-C4. The finding that Ldh-c is expressed in both somatic tissues and testis of plateau pika provides important implications for more in-depth research into the Ldh-c function in mammals. PMID:23772382

  9. Testis-Specific Lactate Dehydrogenase (LDH-C4) in Skeletal Muscle Enhances a Pika’s Sprint-Running Capacity in Hypoxic Environment

    PubMed Central

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2015-01-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000–5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in Qinghai

  10. [Biological features of a new Echinococcus species (Echinococcus shiquicus) in the east of Qinghai-Tibet Plateau].

    PubMed

    Xiao, Ning; Qiu, Jia-Min; Nakao, M; Li, Tiao-Ying; Chen, Xing-Wang; Schantz, P M; Craig, P S; Ito, A

    2008-08-01

    In the eastern Qinghai-Tibet Plateau region, a variety of domestic and wild mammals are involved in the transmission cycles of Echinococcus species. E. granulosus and E. multilocularis are known being sympatrically distributed in the plateau region. Recently, an unknown Echinococcus species was isolated from infected plateau pika (Ochotona curzoniae) and Tibetan fox (Vulpes ferrilata). The species shows quite distinct characteristics on morphology, genetics, host specificity and geographical distribution from others. It was therefore identified as a new Echinococcus species, Echinococcus shiquicus. This paper discussed the biological genetics and epidemiological features of the species, and proposed hypotheses and considerations for further exploration.

  11. [Food habits and hunting patterns of Tibetan brown bear during warm seasons in Kekexili region on Qinghai-Tibetan Plateau].

    PubMed

    Xu, Ai-Chun; Jiang, Zhi-Gang; Li, Chun-Wang; Cai, Ping

    2010-12-01

    Tibetan brown bear (Ursus arctos pruinosus) is an endemic subspecies of brown bear on the Qinghai-Tibetan plateau. We once reported a preliminary study on the summer food habit of Tibetan brown bear from July to August, 2005 in the Kekexili (Hoh Xil).. However, the hunting modes of the Tibetan brawn bear have not been reported. From July to August, 2009, we collected additional data on food habits and hunting patterns of Tibetan brown bear in the Kekexili region. We found Tibetan brown bears are more raptatorial than vegetarian, and their basal food was plateau pika (Ochotona curzoniae), relative frequency occurrence of pika in the fecal residual of brawn bear was 37.3%, dry weight of pika residuals was 44.7%, respectively, followed by wild yak (Bos grunniens) , 18.7% and 30.2%, and Tibetan antelope (Pantholops hodgsoni) 15.0% and 16.2%. Both prey actively mode and scavenge mode were used by Tibetan brown bears in Kekexili. Tibetan brawn bears actively dug and hunted for pika and scavenged bodies of wild yak, Tibetan antelope and Tibetan gazelle. We observed that Tibetan brawn bears spent about 10% of their time to dig and to hunt for pika but we had never seen Tibetan brawn bears actively hunted large mammals such as wild yak, Tibetan antelope and Tibetan gazelle. The total amount of Tibetan antelope, Tibetan gazelle and wild yak ingested by Tibetan brown bear through scavenge was about the same amount of Plateau pika and Himalayan marmot (Marmota himalayana) eaten by the bear.

  12. [Change in the habitat of Yersinia pestis in the Gorno-Altaisk natural focus of plague].

    PubMed

    Korzun, V M; Chipanin, E V; Balakhonov, S V; Denisov, A V; Rozhdestvenskiĭ, E N; Mihaĭlov, E P; Iarygina, M B; Kosilko, S A

    2014-01-01

    The paper analyzes the change that occurred in the habitat of the causative agent of plague in its Gorno-Altaisk natural focus in 1961 to 2012. Since 1961 when the plague microbe was found to come from the southern slopes of the Saylyugem mountain range, which are located in Mongolia, to the northern slopes situated in Russia, a gradual expansion of the habitat of Yersenia pestis subsp. altaica had commenced in South-Eastern Altai. During the considered period, the area where epizootic manifestations were registered showed an 11-fold increase. In most cases, the spread of the plague pathogen within the focus was natural and occurred in the successive and closely related settlements of Mongolian pikas (Ochotona pallasi). By now, the plague microbe has been widely distributed in three populations of this small animal, which inhabit the territory of South-Eastern Altai.

  13. Dual infection of animal hosts with different Echinococcus species in the eastern Qinghai-Tibet plateau region of China.

    PubMed

    Xiao, Ning; Nakao, Minoru; Qiu, Jiamin; Budke, Christine M; Giraudoux, Patrick; Craig, Philip S; Ito, Akira

    2006-08-01

    The eastern Qinghai-Tibet plateau of China is a highly endemic region of echinococcosis where Echinococcus granulosus sensu stricto (sheep strain), Echinococcus multilocularis, and Echinococcus shiquicus are distributed sympatrically. We developed a polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) method for the identification of the three species in this region. The PCR-RFLP showed the dual infection of animals with different Echinococcus spp. The first case was a domestic dog concurrently infected with adults of E. granulosus and E. multilocularis. The second case was a plateau pika (Ochotona curzoniae) harboring metacestodes of E. multilocularis and E. shiquicus in the liver. The high susceptibility of some mammalian hosts to the parasites and the high prevalence of the three co-endemic species probably increase the chance of mixed infections in the eastern Tibetan plateau.

  14. Echinococcus shiquicus, a new species from the Qinghai-Tibet plateau region of China: discovery and epidemiological implications.

    PubMed

    Xiao, Ning; Qiu, Jiamin; Nakao, Minoru; Li, Tiaoying; Yang, Wen; Chen, Xingwang; Schantz, Peter M; Craig, Philip S; Ito, Akira

    2006-01-01

    In Shiqu County of the Qinghai-Tibet plateau, many wild and domestic mammals are involved in the transmission cycles of Echinococcus spp. Echinococcus multilocularis and Echinococcus granulosus genotype G1 (sheep strain) are sympatrically distributed in the plateau. In 1995, we identified a unique strobilate stage of Echinococcus from the Tibetan fox, Vulpes ferrilata, but considered it to be a variant of E. multilocularis. Subsequent molecular genetic studies revealed that a hydatid cyst from the plateau pika, Ochotona curzoniae, had unique mitochondrial DNA sequences which are dissimilar to any published sequences of Echinococcus. The same sequences were subsequently found in adult worms from Tibetan foxes. Morphological, genetic and ecological features of the cestode led us to designate a new species Echinococcus shiquicus. E. shiquicus has been found at other areas surveyed on the plateau; however, no infections in humans caused by E. shiquicus have been yet identified.

  15. Crushed and injected buprenorphine tablets: characteristics of princeps and generic solutions.

    PubMed

    Bouquié, Régis; Wainstein, Laura; Pilet, Paul; Mussini, Jean-Marie; Deslandes, Guillaume; Clouet, Johann; Dailly, Eric; Jolliet, Pascale; Victorri-Vigneau, Caroline

    2014-01-01

    Self-injection of high-dose buprenorphine is responsible for well-described complications. In 2011, we have been alerted by unusual but serious cutaneous complication among injection buprenorphine users. A prospective data collection identified 30 cases of necrotic cutaneous lesions after injection of filtered buprenorphine solution, among which 25 cases occurred following injection of buprenorphine generics. The main goal of our study was to put forward particularities that could explain the cutaneous complications, by qualitatively and quantitatively confronting particles present in Subutex and generics solutions. We used the same protocol that injected-buprenorphine users: generic or subutex tablets were crushed in sterile water and filtered through 2 filters commonly used (cotton-pad and sterifilt). Solutions were analyzed by laser granulometry, flow cytometry and scanning electron microscopy. We have highlighted the wide variation of the quantity and the size of the particles present in solution between the two drugs after cotton-pad filtration. The proportion of particles <10 µm is systematically higher in the generic solutions than with Subutex. All of the insoluble particles found in generic solutions contain silica, whereas non- organic element was to be identified in the insoluble particles of Subutex. One skin biopsy obtained from one patient who developed a necrotic lesion after intravenous injection of filtrated solution of buprenorphine generic, shows non-organic elements. Identification of particles in situ enables us to confirm the presence of silica in the biopsy. Actually the monitoring of patient receiving generic of buprenorphine must be strengthened.

  16. The link between independent acquisition of intracellular gamma-endosymbionts and concerted evolution in Tremblaya princeps

    PubMed Central

    López-Madrigal, Sergio; Latorre, Amparo; Moya, Andrés; Gil, Rosario

    2015-01-01

    Many insect species establish mutualistic symbiosis with intracellular bacteria that complement their unbalanced diets. The betaproteobacterium “Candidatus Tremblaya” maintains an ancient symbiosis with mealybugs (Hemiptera: Pseudococcidae), which are classified in subfamilies Phenacoccinae and Pseudococcinae. Most Phenacoccinae mealybugs have “Candidatus Tremblaya phenacola” as their unique endosymbiont, while most Pseudococcinae mealybugs show a nested symbiosis (a bacterial symbiont placed inside another one) where every “Candidatus Tremblaya princeps” cell harbors several cells of a gammaproteobacterium. Genomic characterization of the endosymbiotic consortium from Planococcus citri, composed by “Ca. Tremblaya princeps” and “Candidatus Moranella endobia,” unveiled several atypical features of the former's genome, including the concerted evolution of paralogous loci. Its comparison with the genome of “Ca. Tremblaya phenacola” PAVE, single endosymbiont of Phenacoccus avenae, suggests that the atypical reductive evolution of “Ca. Tremblaya princeps” could be linked to the acquisition of “Ca. Moranella endobia,” which possess an almost complete set of genes encoding proteins involved in homologous recombination. In order to test this hypothesis, we performed comparative genomics between “Ca. Tremblaya phenacola” and “Ca. Tremblaya princeps” and searched for the co-occurrence of concerted evolution and homologous recombination genes in endosymbiotic consortia from four unexplored mealybug species, Dysmicoccus boninsis, Planococcus ficus, Pseudococcus longispinus, and Pseudococcus viburni. Our results support a link between concerted evolution and nested endosymbiosis. PMID:26161080

  17. Crushed and Injected Buprenorphine Tablets: Characteristics of Princeps and Generic Solutions

    PubMed Central

    Bouquié, Régis; Wainstein, Laura; Pilet, Paul; Mussini, Jean-Marie; Deslandes, Guillaume; Clouet, Johann; Dailly, Eric; Jolliet, Pascale; Victorri-Vigneau, Caroline

    2014-01-01

    Self-injection of high-dose buprenorphine is responsible for well-described complications. In 2011, we have been alerted by unusual but serious cutaneous complication among injection buprenorphine users. A prospective data collection identified 30 cases of necrotic cutaneous lesions after injection of filtered buprenorphine solution, among which 25 cases occurred following injection of buprenorphine generics. The main goal of our study was to put forward particularities that could explain the cutaneous complications, by qualitatively and quantitatively confronting particles present in Subutex and generics solutions. We used the same protocol that injected-buprenorphine users: generic or subutex tablets were crushed in sterile water and filtered through 2 filters commonly used (cotton-pad and sterifilt). Solutions were analyzed by laser granulometry, flow cytometry and scanning electron microscopy. We have highlighted the wide variation of the quantity and the size of the particles present in solution between the two drugs after cotton-pad filtration. The proportion of particles <10 µm is systematically higher in the generic solutions than with Subutex. All of the insoluble particles found in generic solutions contain silica, whereas non- organic element was to be identified in the insoluble particles of Subutex. One skin biopsy obtained from one patient who developed a necrotic lesion after intravenous injection of filtrated solution of buprenorphine generic, shows non-organic elements. Identification of particles in situ enables us to confirm the presence of silica in the biopsy. Actually the monitoring of patient receiving generic of buprenorphine must be strengthened. PMID:25474108

  18. Molecular authentication of the animal crude drug Sailonggu (bone of Myospalax baileyi).

    PubMed

    Zhou, Caiquan; Zhou, Kaiya; Zhang, Shaolai

    2004-11-01

    Two pairs of allele-specific diagnostic primers (SL1L/SL1H and SL2L/SL2H) for distinguishing the Chinese crude drug Sailonggu (bone of plateau zokor, Myospalax baileyi) from its substitutes were designed based on complete sequences of mitochondrial 12S rRNA and cytochrome b genes of the original animals of Myospalacinae, bamboo rat Rhizomys sinensis and black lipped pika Ochotona curzoniae. Total DNA was extracted from crude drug samples and original animals. Allele-specific diagnostic PCRs were performed using these primers with the total DNA as a template annealing at 65 degrees C. Positive amplifications were obtained from all DNA templates of Sailonggu and M. baileyi, whereas negative amplifications resulted from those of other zokors, the bamboo rat and black lipped pika. These results indicate that Sailonggu samples can be definitely distinguished from their substitutes by diagnostic PCR, and no incorrect discrimination was found under the same reaction conditions. Each of the two diagnostic primer pairs can be used to distinguish crude drug Sailonggu from its substitutes or adulterants. The three Sailonggu samples studied were diagnosed as genuine Sailonggu. In addition, the results of sequence alignment and phylogenetic analysis are congruent with that of the allele-specific diagnostic PCR.

  19. Comparative Morphology of Premolar Foramen in Lagomorphs (Mammalia: Glires) and Its Functional and Phylogenetic Implications

    PubMed Central

    Fostowicz-Frelik, Łucja; Meng, Jin

    2013-01-01

    Lagomorphs (a group that consists of pikas, hares, rabbits and allies) are notable for their conservative morphology retained for most of their over 50 million years evolutionary history. On the other hand, their remarkable morphological uniformity partly stems from a considerable number of homoplasies in cranial and dental structures that hamper phylogenetic analyses. The premolar foramen, an opening in the palate of lagomorphs, has been characterized as an important synapomorphy of one clade, Ochotonidae (pikas). Within Lagomorpha, however, its phylogenetic distribution is much wider, the foramen being present not only in all ochotonids but also in leporids and stem taxa; its morphology and incidence also varies considerably across the order, even intraspecifically. In this study, we provide a broad survey of the taxonomic distribution of the premolar foramen in extant and fossil Lagomorpha and describe in detail the morphological variation of this character within the group. Micro-computed tomography was used to examine the hard palate and infraorbital groove morphology in Poelagus (Leporidae) and Ochotona. Scans revealed the course and contacts of the canal behind the premolar foramen and structural differences between the two crown clades. We propose that the premolar foramen has evolved independently in several lineages of Lagomorpha, and we discuss development and function of this foramen in the lagomorph skull. This study shows the importance of comprehensive studies on phylogenetically informative non-dental characters in Lagomorpha. PMID:24278178

  20. Expression of HIF-1alpha and VEGF in skeletal muscle of plateau animals in response to hypoxic stress.

    PubMed

    Xie, H-C; He, J-P; Zhu, J-F; Li, J-G

    2014-01-01

    Hypoxia-inducible factor-1alpha (HIF-1alpha) transcriptionally regulates expression of several target genes in protecting tissues against hypoxia. With hypoxic stress, vascular endothelial growth factor (VEGF) is a signal protein produced by cells and further contributes to improvement of vascular functions and restoring the oxygen supply to tissues. In this current study, we first hypothesized that the protein levels of HIF-1alpha and VEGF are reduced in skeletal muscles of plateau animals [China Qinghai-Tibetan plateau pikas (ochotona curzoniae)] in response to hypoxia as compared with control animals [normal lowland Sprague-Dawley (SD) rats]. We further hypothesized that HIF-1alpha plays a role in regulating expression of VEGF in skeletal muscle. Note that HIF-1alpha and VEGF were determined by using two-site immunoenzymatic assay (ELISA) methods. Our results demonstrated that hypoxic stress induced by exposure of lower O(2) (6 h) significantly increased the levels of HIF-1alpha and VEGF in the oxidative and glycolytic muscles of SD rats and pikas (P<0.05 vs. normoxic conditions). Notably, the increases in HIF-1alpha and VEGF were significantly less in pikas (P<0.05, vs. SD controls) than in SD rats. In addition, a linear relationship was observed between amplified HIF-1alpha and VEGF in oxidative muscle (r=0.76 and P<0.01) and glycolytic muscle (r=0.72 and P<0.01) and inhibiting HIF-1alpha significantly decreased expression of VEGF induced by hypoxic stress in skeletal muscles (P<0.05). Overall, our findings suggest that (1) responsiveness of HIF-1alpha and VEGF in skeletal muscles to hypoxic stress is blunted in plateau animals, and (2) HIF-1alpha has a regulatory effect on VEGF under hypoxic environment.

  1. Return to Beringia: parasites reveal cryptic biogeographic history of North American pikas

    USDA-ARS?s Scientific Manuscript database

    As a dispersal corridor between the northern continents, the Bering Land Bridge played a key role in shaping Holarctic biotas. The Beringian paradigm identifies the land bridge as a zone of predominantly eastward expansion from Eurasia and a staging area for subsequent colonization of lower latitude...

  2. Landscape effects on gene flow for a climate-sensitive montane species, the American pika

    Treesearch

    Jessica A. Castillo; Clinton W. Epps; Anne R. Davis; Samuel A. Cushman

    2014-01-01

    Climate change is arguably the greatest challenge to conservation of our time. Most vulnerability assessments rely on past and current species distributions to predict future persistence but ignore species’ abilities to disperse through landscapes, which may be particularly important in fragmented habitats and crucial for long-term persistence in changing...

  3. Expertly validated models and phylogenetically-controlled analysis suggests responses to climate change are related to species traits in the order lagomorpha.

    PubMed

    Leach, Katie; Kelly, Ruth; Cameron, Alison; Montgomery, W Ian; Reid, Neil

    2015-01-01

    Climate change during the past five decades has impacted significantly on natural ecosystems, and the rate of current climate change is of great concern among conservation biologists. Species Distribution Models (SDMs) have been used widely to project changes in species' bioclimatic envelopes under future climate scenarios. Here, we aimed to advance this technique by assessing future changes in the bioclimatic envelopes of an entire mammalian order, the Lagomorpha, using a novel framework for model validation based jointly on subjective expert evaluation and objective model evaluation statistics. SDMs were built using climatic, topographical, and habitat variables for all 87 lagomorph species under past and current climate scenarios. Expert evaluation and Kappa values were used to validate past and current models and only those deemed 'modellable' within our framework were projected under future climate scenarios (58 species). Phylogenetically-controlled regressions were used to test whether species traits correlated with predicted responses to climate change. Climate change is likely to impact more than two-thirds of lagomorph species, with leporids (rabbits, hares, and jackrabbits) likely to undertake poleward shifts with little overall change in range extent, whilst pikas are likely to show extreme shifts to higher altitudes associated with marked range declines, including the likely extinction of Kozlov's Pika (Ochotona koslowi). Smaller-bodied species were more likely to exhibit range contractions and elevational increases, but showing little poleward movement, and fecund species were more likely to shift latitudinally and elevationally. Our results suggest that species traits may be important indicators of future climate change and we believe multi-species approaches, as demonstrated here, are likely to lead to more effective mitigation measures and conservation management. We strongly advocate studies minimising data gaps in our knowledge of the Order

  4. [Inhibition effect of hypoxia on humoral immunity of rats].

    PubMed

    Bai, H B; Du, J Z; Jia, H W

    1997-04-01

    To study the effect of hypoxia on humoral immunity function of rat and Ochotona curzoniae (pika), the specific antibody production to novel antigen IgG and immunoresponse to sheep red blood cell (hemolysin forming) were measured. The results show that hypoxia at altitude of 5 km and 7 km for 10 d resulted respectively in 10.3% (P < 0.05) and 21.9% (P < 0.05) decrement in hemolysin formation in rats, as compared with the control group kept at 2.3 km. When the rats were secondarily immunized and kept at the same hypoxia for 10 d, the reduction in hemolysin formation was 4.2% (P < 0.05) and 4.6% (P < 0.05) for the two respective altitudes. These changes, however, were not found in pikas. When rats were immunized two days before hypoxia, 5 km hypoxia for 5 d and 8 d failed to suppress hemolysin formation. Intracerebroventricular (i.c.v.) injection of CRF (1.0 microgram/rat), decreased hemolysin formation and production of IgG by 8.6% (P < 0.05) and 14.0% (P < 0.05) respectively, but intraperitoneal (i.p.) injection of CRF (1.0 microgram/rat) had no effect. On the other hand, i.c.v. injection of CRF receptor antagonist (alpha-helical CRF (9-41), 50 micrograms/rat) prior to 7 km hypoxia caused a hypoxia-induced suppression of IgG production from 24.2% to 12.1% (P < 0.05). Adrenalectomy in rats lowered hemolysin formation by 6.6% (P < 0.05). The above results demonstrate that hypoxia suppresses humoral immunity function and alters initial antigen processing probably through an increase of CRF in the central nervous system.

  5. Expertly Validated Models and Phylogenetically-Controlled Analysis Suggests Responses to Climate Change Are Related to Species Traits in the Order Lagomorpha

    PubMed Central

    Leach, Katie; Kelly, Ruth; Cameron, Alison; Montgomery, W. Ian; Reid, Neil

    2015-01-01

    Climate change during the past five decades has impacted significantly on natural ecosystems, and the rate of current climate change is of great concern among conservation biologists. Species Distribution Models (SDMs) have been used widely to project changes in species’ bioclimatic envelopes under future climate scenarios. Here, we aimed to advance this technique by assessing future changes in the bioclimatic envelopes of an entire mammalian order, the Lagomorpha, using a novel framework for model validation based jointly on subjective expert evaluation and objective model evaluation statistics. SDMs were built using climatic, topographical, and habitat variables for all 87 lagomorph species under past and current climate scenarios. Expert evaluation and Kappa values were used to validate past and current models and only those deemed ‘modellable’ within our framework were projected under future climate scenarios (58 species). Phylogenetically-controlled regressions were used to test whether species traits correlated with predicted responses to climate change. Climate change is likely to impact more than two-thirds of lagomorph species, with leporids (rabbits, hares, and jackrabbits) likely to undertake poleward shifts with little overall change in range extent, whilst pikas are likely to show extreme shifts to higher altitudes associated with marked range declines, including the likely extinction of Kozlov’s Pika (Ochotona koslowi). Smaller-bodied species were more likely to exhibit range contractions and elevational increases, but showing little poleward movement, and fecund species were more likely to shift latitudinally and elevationally. Our results suggest that species traits may be important indicators of future climate change and we believe multi-species approaches, as demonstrated here, are likely to lead to more effective mitigation measures and conservation management. We strongly advocate studies minimising data gaps in our knowledge of the

  6. Differential responsiveness in VEGF receptor subtypes to hypoxic stress in various tissues of plateau animals.

    PubMed

    Xie, Hui-Chun; Li, Jin-Gang; He, Jian-Ping

    2017-05-04

    With hypoxic stress, hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) are elevated and their responses are altered in skeletal muscles of plateau animals [China Qinghai-Tibetan plateau pikas (Ochotona curzoniae)] as compared with control animals [normal lowland Sprague-Dawley (SD) rats]. The results indicate that HIF-1alpha and VEGF are engaged in physiological functions under hypoxic environment. The purpose of the current study was to examine the protein levels of VEGF receptor subtypes (VEGFRs: VEGFR-1, VEGFR-2 and VEGFR-3) in the end organs, namely skeletal muscle, heart and lung in response to hypoxic stress. ELISA and Western blot analysis were employed to determine HIF-1alpha and the protein expression of VEGFRs in control animals and plateau pikas. We further blocked HIF-1alpha signal to determine if HIF-1alpha regulates alternations in VEGFRs in those tissues. We hypothesized that responsiveness of VEGFRs in the major end organs of plateau animals is differential with insult of hypoxic stress and is modulated by low oxygen sensitive HIF-1alpha. Our results show that hypoxic stress induced by exposure of lower O(2) for 6 h significantly increased the levels of VEGFR-2 in skeletal muscle, heart and lung and the increases were amplified in plateau pikas. Our results also demonstrate that hypoxic stress enhanced VEGFR-3 in lungs of plateau animals. Nonetheless, no significant alternations in VEGFR-1 were observed in those tissues with hypoxic stress. Moreover, we observed decreases of VEGFR-2 in skeletal muscle, heart and lung; and decreases of VEGFR-3 in lung following HIF-1alpha inhibition. Overall, our findings suggest that in plateau animals 1) responsiveness of VEGFRs is different under hypoxic environment; 2) amplified VEGFR-2 response appears in skeletal muscle, heart and lung, and enhanced VEGFR-3 response is mainly observed in lung; 3) HIF-1alpha plays a regulatory role in the levels of VEGFRs. Our results

  7. Paleobiogeographic Changes at the Pleistocene-Holocene Boundary near Pintwater Cave, Southern Nevada

    NASA Astrophysics Data System (ADS)

    Hockett, Bryan Scott

    2000-03-01

    In 1996, approximately 70,000 mammal and lizard bones were recovered from Pintwater Cave in the northern Mojave Desert of southern Nevada. These bones date between 32,000 and 7350 14C yr B.P. Between 32,000 and 10,100 14C yr B.P. the local fauna consisted of a mix of xeric- and cool/mesic-adapted species. Ochotona princeps and Thomomys talpoides then occupied the region, although these animals were extirpated by the onset of the middle Holocene. Sauromalus obesus and Dipodomys deserti probably migrated to the region during the latest Pleistocene. Dipsosaurus dorsalis entered the Pintwater Cave record after 8000 14C yr B.P. Consistent with climatic interpretations for the northern Great Basin, these data suggest a cool and moist latest Pleistocene climate for the northern Mojave Desert. In contrast to the northern Great Basin, however, this region experienced predictable summer precipitation coupled with increasingly warmer winters by 10,100 14C yr B.P. In both regions, the warm middle Holocene began ca. 8300 14C yr B.P. However, whereas the northern Great Basin probably experienced warm and dry conditions at that time, the northern Mojave Desert remained warm with relatively predictable summer precipitation. The modern northern Mojave Desert biota probably was not established until after 8300 14C yr B.P.

  8. Two new species of Schizorchis (Cestoda: Anoplocephalidae) from leporids (Lagomorpha: Leporidae) in China.

    PubMed

    Cai, Kuizheng; Bai, Jialin; Chen, Shien

    2012-10-01

    Four specimens of wild leporids, Lepus capensis Linnaeus, 1758, in Longde County, Ningxia Hui Autonomous Region (NXHAR), and 40 domestic rabbits, Oryctolagus cuniculus (Linnaeus, 1758) (20 from Xiji County, NXHAR, and 20 from Jingning County, Gansu Province) were examined for the presence of helminth parasites. Two new cestode species of Schizorchis Hansen, 1948 (Anoplocephalidae), were found: Schizorchis sinensis sp. n. from L. capensis and Schizorchis oryctolagi sp. n. from domestic rabbits. Schizorchis sinensis sp. n. is distinguished from all the species in the genus from pikas, Ochotona spp. (Lagomorpha: Ochotonidae) by having much longer strobila, a larger cirrus sac, a greater number of segments, and more numerous testes. The morphology of S. oryctolagi n. sp. is most similar to that of S. sinensis. It is distinguished from the latter species by its relatively small strobila, larger number of segments, smaller size of eggs, and much larger cirrus sac, which is substantially extending in a medial direction. In addition, a genital papilla is present in S. sinensis , but absent in S. oryctolagi. These findings indicate that species of Schizorchis are widespread in leporid mammals, contrary to the widespread opinion that the latter genus is specific to ochotonid lagomorph mammals. They are congruent, however, with the hypothesis of a close phylogenetic relationship between species of Schizorchis and Mosgovoyia. The occurrence of Schizorchis spp. in leporids is considered relict, vestigial from wider geographical and host ranges of this parasite genus during the Pleistocene.

  9. Nonneutral evolution of tandem repeats in the mitochondrial DNA control region of lagomorphs.

    PubMed

    Casane, D; Dennebouy, N; de Rochambeau, H; Mounolou, J C; Monnerot, M

    1997-08-01

    The mitochondrial DNA of the European rabbit (Oryctolagus cuniculus) contains a tandem array of 153-bp repeats in the vicinity of the replication origin of the H-stand. Variation among molecules in the number of these repeats results in inter- and intraindividual length polymorphism (heteroplasmy). Generally, in an individual, one predominant molecular type is observed, the others representing a low percentage of the mtDNA content. At the tissue level, we observe a particular distribution of this polymorphism in the gonads compared with liver, kidneys, or brain, implying a relationship between the differentiation status of the cells and the types of new mtDNA molecules which appear and accumulate during lifetime. Similar tandem repeats were also found in the mtDNA noncoding region of European hares (Lepus europaeus), a cottontail (Sylvilagus floridanus), and a pika (Ochotona rufescens). The lengths and the sequences of these units evolve rapidly and in a concerted way, but the number of repeats is maintained in a narrow range, and an internal 20-bp segment is highly conserved. Constraints restrict the evolution of the primary sequence of these repeated units, the number of which is probably controlled by a stabilizing selection.

  10. Surface EMG-recordings using a miniaturised matrix electrode: a new technique for small animals.

    PubMed

    Biedermann, F; Schumann, N P; Fischer, M S; Scholle, H C

    2000-04-01

    A new method for multichannel surface-EMG measurements in small animals is presented. The underlying scientific aim is the characterisation of the spreading and the co-ordination of skeletal muscle activation between different muscles or muscle parts, depending on various motor tasks. The myoelectrical signals were recorded monopolarly by a 16-channel matrix electrode on the muscle surface directly under the skin on the fascia of the investigated muscle, without damaging the muscle. Surface-EMG's were recorded for at least 5 days after surgery without electrical interferences. During defined motor tasks, the projection of the myoelectrical activation of the different parts of the M. triceps brachii of rats (Rattus norvegicus), pikas (Ochotona rufescens) and cuis (Galea musteloides) or the M. anconeus of toads (Bufo marinus) on the muscle surface was mapped. The locomotion of the investigated animals was monitored by a three-dimensional kinematic analysis (video and/or high-speed cineradiography). There was no perceptible influence from application of EMG matrix electrode. The miniaturised matrix electrode seemed practicable in gaining insight into changes in myoelectrical activation patterns (EMG mapping). This allows a characterisation of the intramuscular co-ordination processes corresponding to the actual morphofunctional state of the investigated animals.

  11. Antioxidant action of ganghwayakssuk (Artemisia princeps Pamp.) in combination with ascorbic acid to increase the shelf life in raw and deep fried chicken nuggets.

    PubMed

    Hwang, Ko-Eun; Choi, Yun-Sang; Choi, Sun-Mi; Kim, Hyun-Wook; Choi, Ji-Hun; Lee, Mi-Ai; Kim, Cheon-Jei

    2013-11-01

    Raw and deep fried chicken nuggets containing various levels of ganghwayakssuk ethanolic extract (GE) in combination with ascorbic acid (Aa) were evaluated for shelf-life during refrigerated storage (4°C). The pH and color (lightness, redness, and yellowness) values of raw and deep fried samples were significantly affected by the addition of GE (P<0.05). All antioxidant combinations except for Aa+GE 0.01 were effective at delaying lipid oxidation (CD, POV, and TBARS) when compared to the control or Aa. Raw samples with GE 0.2 and Aa+GE 0.1 exhibited lower bacterial populations during storage. The sensory characteristics (color, juiciness, flavor, tenderness, and overall acceptability) did not differ significantly in all deep fried chicken nugget samples, except color, whereas storage time had a significant effect (P<0.05). The results suggest the possibility of utilizing raw and deep fried chicken nuggets with a mixture of ganghwayakssuk and ascorbic acid for the increase of shelf-life and quality. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. [Epidemiological survey on echinococcosis in Darlag County of Qinghai Province].

    PubMed

    Han, Xiu-min; Wang, Hu; Cai, Hui-xia; Ma, Xiao; Liu, Yu-fang; Wei, Bing-hui; Ito, A; Craig, P S

    2009-02-28

    To make an epidemiological investigation on echinococcosis in Darlag County, Guoluo Tibetan Autonomous Prefecture of Qinghai Province. Local participants were screened for echinococcosis using B ultrasound from August to September in 2007. IHA was carried out to detect antibody in human sera. Indirect ELISA using recombinant-AgB and Em18 antigen was conducted to further diagnose the human alveolar echinococcosis (AE) and cystic echinococcosis (CE) . The prevalence of echinococcosis in wild rodents, yaks, sheep and dogs was examined either by dissection or through slaughterhouses. Adult worms and hydatid cysts were detected by PCR-RFLP to discriminate 3 Echinococcus species and genotype of Eg. Dog feces were tested by double antibody sandwich ELISA method to confirm the coproantigen positive rate. 1723 people were examined by ultrasound and 236 were clinically diagnosed as hydatid diseases with an overall morbidity of 13.7%, of which 5.5% were CE and 8.2% were AE. Prevalence in males and females was 11.6% and 15.6% respectively with a statistically significant difference (chi2=7.0, P< 0.05) . Prevalence in herdsmen and monks/nuns was as high as 23.0% and 13.2%, respectively. Adult worms were found in 5 out of 9 stray dogs by necropsy. 27 of 239 pikas (Ochotona curzoniae) were infected by E. shiquicus (11.3%). CE prevalence in sheep and yaks was 26.4% and 5/16 respectively. The Eg genotype was G1 (sheep strain). Three species of Echinococcus, e.g. E. granulosus, E. multilocularis and E. shiquicus are all prevalent in Darlag County. The prevalence of both AE and CE in human population is high in the area. Domestic dogs are the primary definitive host for both E. granulosus and E. multilocularis.

  13. Inhibitory effect of an ethanol extract of a rice bran mixture including Angelica gigas, Cnidium officinale, Artemisia princeps and Camellia sinensis on Brucella abortus uptake by professional and non-professional phagocytes.

    PubMed

    Hop, Huynh Tan; Arayan, Lauren Togonon; Reyes, Alisha Wehdnesday Bernardo; Huy, Tran Xuan Ngoc; Baek, Eun Jin; Min, WonGi; Lee, Hu Jang; Lee, Chun Hee; Rhee, Man Hee; Kim, Suk

    2017-09-05

    In this study, we evaluated the inhibitory effect of a rice bran mixture extract (RBE) on Brucella (B.) abortus pathogenesis in professional (RAW 264.7) and non-professional (HeLa) phagocytes. We fermented the rice bran mixture and then extracted with 50% ethanol followed by gas chromatography-mass spectrometry to identify components in RBE. Our results clearly showed that RBE caused a significant reduction in the adherence of B. abortus in both cell lines. Furthermore, analysis of phagocytic signaling proteins by Western blot revealed that RBE pretreatment resulted in inhibition of phosphorylation of JNK, ERK and p38, leading to decline of internalization compared with the controls. Additionally, the intensity of F-actin observed by fluorescence microscopy and FACS was remarkably reduced in RBE-pretreated cells compared with control cells. However, the intracellular replication of B. abortus within phagocytes was not affected by RBE. Taken together, these findings suggest that the phagocytic receptor blocking and suppressive effects of RBE on the MAPK-linked phagocytic signaling pathway could negatively affect the invasion of B. abortus into phagocytes.

  14. Cold adaptive thermogenesis in small mammals from different geographical zones of China.

    PubMed

    Li, Q; Sun, R; Huang, C; Wang, Z; Liu, X; Hou, J; Liu, J; Cai, L; Li, N; Zhang, S; Wang, Y

    2001-07-01

    The mechanisms of thermogenesis and thermoregulation were studied in the tree shrew (Tupaia belangeri) and greater vole (Eothenomys miletus) of the subtropical region, and Brandt's vole (Microtus brandti), Mongolian gerbil (Meriones unguiculatus), Daurian ground squirrel (Spermophilus dauricus) and plateau pika (Ochotona curzoniae) of the northern temperate zone. Resting metabolic rate (RMR) and non-shivering thermogenesis (NST) increased significantly in T. belangeri, E. miletus, M. brandti and M. unguiculatus after cold acclimation (4 degrees C) for 4 weeks. In T. belangeri, the increase in RMR and thermogenesis at liver cellular level were responsible for enhancing the capacity of enduring cold stress, and homeothermia was simultaneously extended. Stable body temperature in M. brandti, E. miletus, M. unguiculatus and O. curzoniae was maintained mainly through increase in NST, brown adipose tissue (BAT) mass and its mitochondrial protein content, and the upregulation of uncoupling protein (UCP1) mRNA, as well as enhancement of the activity of cytochrome C oxidase, alpha-glycerophosphate oxidase and T(4) 5'-deiodinase in BAT mitochondria. The RMR in O. curzoniae and euthermic S. dauricus was not changed, while NST significantly increased during cold exposure; the former maintained their stable body temperature and mass, while body temperature in the latter declined by 4.8 degrees C. The serum T(3) concentration or ratio of T(3)/T(4) in all the species was enhanced after cold acclimation. Results indicated that: (1) the adaptive mechanisms of T. belangeri residing in the subtropical region to cold are primarily by increasing RMR and secondly by increasing NST, and the mechanisms of thermogenesis are similar to those in tropical mammals; (2) in small mammals residing in northern regions, the adaptation to cold is chiefly to increase NST; (3) the mechanism of cold-induced thermogenesis in E. miletus residing in subtropical and high mountain regions is similar to that

  15. JPRS Report, Soviet Union, Military Affairs.

    DTIC Science & Technology

    1988-12-08

    of soldiers and sent them to Igor Pika , a friend in his hometown. He also engaged in "com- mercial" deals previously, but a misfire occurred here...his service on a larger scale. That same Pika always brought items to him. The question naturally arises: why was the "com- mercial" activity of the...marketeer Pika ," said Khaborskaya. "My son reproached me that I do not know how to live and that there is no money, and Igor always has money—he will

  16. 75 FR 6437 - Endangered and Threatened Wildlife and Plants; 12-month Finding on a Petition to List the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... and Weston 1990, p. 2). American pikas are generalist herbivores that select different classes of..., pp. 2- 4). A generalist herbivore that does not hibernate, the species relies on haypiles of...

  17. Comparative Study of Erythrocyte Glycolytic Enzymes in Man and in Two Species of Lagomorphae

    PubMed Central

    Puget, A.; Gouarderes, Christine; Vergnes, H.

    1974-01-01

    The authors made a comparative study of red cell enzyme glycolysis in man and in two species of Lagomorphae, the pika and the rabbit. The activities of the 12 enzymes of Embden-Meyerhoff pathway and of the two dehydrogenases of pentose shunt (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase) were determined. Phosphoglycerate kinase and pyruvate kinase showed quite similar activities in pika erythrocytes and in erythrocytes from human umbilical cord. The levels of these enzymes differed significantly in the pika and in the rabbit. No differences were noted between pyruvate kinases from the rabbit and the neonatal man. The other activities gave values either identical to those found in the adult man or intermediate between the adult and the neonatal man. In the rabbit the levels of glycolitic enzymes were generally lower than in the pika except for lactate dehydrogenase and glycose-6-phosphate dehydrogenase. Some characteristics of erythrocyte metabolism specific to the pika may account for the differences observed in this species. The influence of red cell age cannot explain the variations observed for no significant reticulocytosis was observed in the circulating blood. The percentages found in the pika and the rabbit were essentially identical at determination. PMID:4277413

  18. Characterization of Nutritional Composition, Antioxidative Capacity, and Sensory Attributes of Seomae Mugwort, a Native Korean Variety of Artemisia argyi H. Lév. & Vaniot

    PubMed Central

    Kim, Jae Kyeom; Shin, Eui-Cheol; Lim, Ho-Jeong; Choi, Soo Jung; Kim, Cho Rong; Suh, Soo Hwan; Kim, Chang-Ju; Park, Gwi Gun; Park, Cheung-Seog; Kim, Hye Kyung; Choi, Jong Hun; Song, Sang-Wook; Shin, Dong-Hoon

    2015-01-01

    Few studies have investigated Seomae mugwort (a Korean native mugwort variety of Artemisia argyi H. Lév. & Vaniot), exclusively cultivated in the southern Korean peninsula, and the possibility of its use as a food resource. In the present study, we compared the nutritional and chemical properties as well as sensory attributes of Seomae mugwort and the commonly consumed species Artemisia princeps Pamp. In comparison with A. princeps, Seomae mugwort had higher contents of polyunsaturated fatty acids, total phenolic compounds, vitamin C, and essential amino acids. In addition, Seomae mugwort had better radical scavenging activity and more diverse volatile compounds than A. princeps as well as favorable sensory attributes when consumed as tea. Given that scant information is available regarding the Seomae mugwort and its biological, chemical, and sensory characteristics, the results herein may provide important characterization data for further industrial and research applications of this mugwort variety. PMID:26550520

  19. Distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan, China.

    PubMed

    Xu, Xiang; Guan, Ya-Yi; Tian, Tian; Wu, Wei-Ping; Wang, Qian; Huang, Yan; Li, Guang-Qing; Wang, Li-Ying

    2011-09-01

    The rodentia and lagomorpha animals are the intermediate hosts of Echinococcus multilocularis, their distribution and infection of this parasite may facilitate the infection of definitive hosts such as dogs. The aim of this study was to determine the distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan, China. A systematic sampling method was used to investigate the density of burrows of rodents and lagomorphs at 97 pasture sites in winter and summer pastureland and remote sensing (RS) technology was used to correlate their densities to the distribution of these animals in different landscape types. Based on the densities of Ochotona curzoniae, Microtus fuscus (dependent variable) and their burrow densities (independent variable) in survey points, regression equations were fitted respectively (Ochotona curzoniae, P < 0.0001, R(2) = 0.8705; Microtus fuscus, P < 0.0001, R(2) = 0.9736). Their burrow density in summer pastureland was higher than in winter pastureland (F = 36.65, P < 0.0001). The burrow densities of Ochotona curzoniae and Microtus fuscus in bareland and half-bareland are higher than in grassland (F = 7.73, P < 0.001). The regression relationship between the densities of Ochotona curzoniae and Microtus fuscus and their burrow densities indicate that the burrow densities could reflect the animal densities and that the burrow density was greater in summer pastureland than in winter pastureland. The main distribution areas of the intermediate hosts were in bareland and half-bareland.

  20. Habitat availability and gene flow influence diverging local population trajectories under scenarios of climate change: a place-based approach.

    PubMed

    Schwalm, Donelle; Epps, Clinton W; Rodhouse, Thomas J; Monahan, William B; Castillo, Jessica A; Ray, Chris; Jeffress, Mackenzie R

    2016-04-01

    Ecological niche theory holds that species distributions are shaped by a large and complex suite of interacting factors. Species distribution models (SDMs) are increasingly used to describe species' niches and predict the effects of future environmental change, including climate change. Currently, SDMs often fail to capture the complexity of species' niches, resulting in predictions that are generally limited to climate-occupancy interactions. Here, we explore the potential impact of climate change on the American pika using a replicated place-based approach that incorporates climate, gene flow, habitat configuration, and microhabitat complexity into SDMs. Using contemporary presence-absence data from occupancy surveys, genetic data to infer connectivity between habitat patches, and 21 environmental niche variables, we built separate SDMs for pika populations inhabiting eight US National Park Service units representing the habitat and climatic breadth of the species across the western United States. We then predicted occurrence probability under current (1981-2010) and three future time periods (out to 2100). Occurrence probabilities and the relative importance of predictor variables varied widely among study areas, revealing important local-scale differences in the realized niche of the American pika. This variation resulted in diverse and - in some cases - highly divergent future potential occupancy patterns for pikas, ranging from complete extirpation in some study areas to stable occupancy patterns in others. Habitat composition and connectivity, which are rarely incorporated in SDM projections, were influential in predicting pika occupancy in all study areas and frequently outranked climate variables. Our findings illustrate the importance of a place-based approach to species distribution modeling that includes fine-scale factors when assessing current and future climate impacts on species' distributions, especially when predictions are intended to manage and

  1. Composition of archaeal, bacterial, and eukaryal RuBisCO genotypes in three Western Pacific arc hydrothermal vent systems.

    PubMed

    Elsaied, Hosam Easa; Kimura, Hiroyuki; Naganuma, Takeshi

    2007-01-01

    We studied the diversity of all forms of the RuBisCO large subunit-encoding gene cbbL in three RuBisCO uncharacterized hydrothermal vent communities. This diversity included the archaeal cbbL and the forms IC and ID, which have not previously been studied in the deep-sea environment, in addition to the forms IA, IB and II. Vent plume sites were Fryer and Pika in the Mariana arc and the Suiyo Seamount, Izu-Bonin, Japan. The cbbL forms were PCR amplified from plume bulk microbial DNA and then cloned and sequenced. Archaeal cbbL was detected in the Mariana samples only. Both forms IA and II were amplified from all samples, while the form IC was amplified only from the Pika and Suiyo samples. Only the Suiyo sample showed amplification of the form ID. The form IB was not recorded in any sample. Based on rarefaction analysis, nucleotide diversity and average pairwise difference, the archaeal cbbL was the most diverse form in Mariana samples, while the bacterial form IA was the most diverse form in the Suiyo sample. Also, the Pika sample harbored the highest diversity of cbbL phylogenetic lineages. Based on pairwise reciprocal library comparisons, the Fryer and Pika archaeal cbbL libraries showed the most significant difference, while Pika and Suiyo showed the highest similarity for forms IA and II libraries. This suggested that the Fryer supported the most divergent sequences. All archaeal cbbL sequences formed unique phylogenetic lineages within the branches of anaerobic thermophilic archaea of the genera Pyrococcus, Archaeoglobus, and Methanococcus. The other cbbL forms formed novel phylogenetic clusters distinct from any recorded previously in other deep-sea habitats. This is the first evidence for the diversity of archaeal cbbL in environmental samples.

  2. [Investigation and identification of varieties of wulingzhi in Qinghai Province].

    PubMed

    Wan, S

    1998-06-01

    This paper reports the investigation and identification of varieties of Wulingzhi used as drugs in Qinghai province. The results show Wulingzhi varieties from the province and the parts of northwest districts are different with the Wulinzhi recorded in China Pharmacopoeia, which has itself special varieties and identified standard, their originals are the excrements from Petaurista xanthotis, Ochotona erythrotis, O. curzoniae. O. daurica and O. causus.

  3. Design, synthesis, and antiviral activity of novel rutin derivatives containing 1, 4-pentadien-3-one moiety.

    PubMed

    Han, Yu; Ding, Yan; Xie, Dandan; Hu, Deyu; Li, Pei; Li, Xiangyang; Xue, Wei; Jin, Linhong; Song, Baoan

    2015-03-06

    Rutin (compound 5) and some compounds (compounds 1-4 and 6) were isolated from Artemisia princeps Pamp (A. princeps Pamp.) and a series of novel rutin derivatives containing 1,4-pentadien-3-one moiety were designed and synthesized. The target compounds were characterized by proton nuclear magnetic resonance spectroscopy ((1)H NMR), carbon nuclear magnetic resonance spectroscopy ((13)C NMR), and ESI-MS. Bioassay results indicated that some of the compounds showed good to excellent antiviral activities against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) at 500 μg/mL in vivo. The 50% effective concentrations (EC50) of the compound 7r against CMV was 394.78 μg/mL, which was better than that of Ningnanmycin (432.22 μg/mL). These results indicated that novel rutin derivatives containing 1,4-pentadien-3-one moiety can effectively control CMV.

  4. Arterial anatomy of the thumb.

    PubMed

    Ames, E L; Bissonnette, M; Acland, R; Lister, G; Firrell, J

    1993-08-01

    The anatomical literature has indicated that the arterial supply to the thumb comes from the princeps pollicis artery. However, this simplified description does not often correlate with intraoperative findings. The purpose of this study was to investigate and clarify this important area of anatomy by dissection of fresh cadaver hands. 40 dissections were completed on 35 intravascularly injected and five non-injected hands. Five patterns were identified. The most common pattern showed both a superficial and deep vessel to the first web space in 54% of specimens. Dominant vessels included the superficial palmar branch of the radial artery in 8%, first palmar metacarpal artery in 18% and dorsal metacarpal artery in 8%. Only three specimens correlated with the textbook description. We conclude that the term "princeps pollicis" is actually a misnomer.

  5. Mealybugs with distinct endosymbiotic systems living on the same host plant.

    PubMed

    Koga, Ryuichi; Nikoh, Naruo; Matsuura, Yu; Meng, Xian-Ying; Fukatsu, Takema

    2013-01-01

    Mealybugs (Homoptera: Coccoidea: Pseudococcidae) possess a large bacteriome consisting of a number of bacteriocytes whose cytoplasm is populated by endosymbiotic bacteria. In many mealybugs of the subfamily Pseudococcinae, a peculiar endosymbiotic configuration has been identified: within the bacteriocytes, the primary betaproteobacterial endosymbiont Tremblaya princeps endocellularly harbor secondary gammaproteobacterial endosymbionts in a nested manner. Meanwhile, some mealybugs of the subfamily Phenacoccinae are associated only with a betaproteobacterial endosymbiont, designated as Tremblaya phenacola, which constitutes a distinct sister clade of T. princeps. However, cytological configuration of the endosymbiotic system in the phenacoccine mealybugs has not been established. Here, we investigated the endosymbiotic systems of the azalea mealybugs Crisicoccus azaleae (Pseudococcinae) and Phenacoccus azaleae (Phenacoccinae) living on the same host plants. Crisicoccus azaleae possessed a nested endosymbiotic system with T. princeps within the bacteriocyte cytoplasm and itself endocellularly harboring gammaproteobacterial cells, whereas P. azaleae exhibited a simple endosymbiotic system in which T. phenacola cells are localized within the bacteriocytes without additional gammaproteobacterial associates. Considering that these mealybugs live on the identical plant phloem sap, these different endosymbiotic consortia likely play similar biological roles for their host insects. The findings presented here should be helpful for future functional and comparative genomics toward elucidating evolutionary pathways of mealybugs and their endosymbionts.

  6. Genetic characterization of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18) with relevant biological roles in lagomorphs

    PubMed Central

    Neves, Fabiana; Abrantes, Joana; Almeida, Tereza; de Matos, Ana Lemos; Costa, Paulo P

    2015-01-01

    ILs, as essential innate immune modulators, are involved in an array of biological processes. In the European rabbit (Oryctolagus cuniculus) IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18 have been implicated in inflammatory processes and in the immune response against rabbit hemorrhagic disease virus and myxoma virus infections. In this study we characterized these ILs in six Lagomorpha species (European rabbit, pygmy rabbit, two cottontail rabbit species, European brown hare and American pika). Overall, these ILs are conserved between lagomorphs, including in their exon/intron structure. Most differences were observed between leporids and American pika. Indeed, when comparing both, some relevant differences were observed in American pika, such as the location of the stop codon in IL-1α and IL-2, the existence of a different transcript in IL8 and the number of cysteine residues in IL-1β. Changes at N-glycosylation motifs were also detected in IL-1, IL-10, IL-12B and IL-15. IL-1α is the protein that presents the highest evolutionary distances, which is in contrast to IL-12A where the distances between lagomorphs are the lowest. For all these ILs, sequences of human and European rabbit are more closely related than between human and mouse or European rabbit and mouse. PMID:26395994

  7. Genetic characterization of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18) with relevant biological roles in lagomorphs.

    PubMed

    Neves, Fabiana; Abrantes, Joana; Almeida, Tereza; de Matos, Ana Lemos; Costa, Paulo P; Esteves, Pedro J

    2015-11-01

    ILs, as essential innate immune modulators, are involved in an array of biological processes. In the European rabbit (Oryctolagus cuniculus) IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18 have been implicated in inflammatory processes and in the immune response against rabbit hemorrhagic disease virus and myxoma virus infections. In this study we characterized these ILs in six Lagomorpha species (European rabbit, pygmy rabbit, two cottontail rabbit species, European brown hare and American pika). Overall, these ILs are conserved between lagomorphs, including in their exon/intron structure. Most differences were observed between leporids and American pika. Indeed, when comparing both, some relevant differences were observed in American pika, such as the location of the stop codon in IL-1α and IL-2, the existence of a different transcript in IL8 and the number of cysteine residues in IL-1β. Changes at N-glycosylation motifs were also detected in IL-1, IL-10, IL-12B and IL-15. IL-1α is the protein that presents the highest evolutionary distances, which is in contrast to IL-12A where the distances between lagomorphs are the lowest. For all these ILs, sequences of human and European rabbit are more closely related than between human and mouse or European rabbit and mouse. © The Author(s) 2015.

  8. The genetic properties of the primary endosymbionts of mealybugs differ from those of other endosymbionts of plant sap-sucking insects.

    PubMed

    Baumann, Linda; Thao, MyLo Ly; Hess, Justin M; Johnson, Marshall W; Baumann, Paul

    2002-07-01

    Mealybugs (Hemiptera, Coccoidea, Pseudococcidae), like aphids and psyllids, are plant sap-sucking insects that have an obligate association with prokaryotic endosymbionts that are acquired through vertical, maternal transmission. We sequenced two fragments of the genome of Tremblaya princeps, the endosymbiont of mealybugs, which is a member of the beta subdivision of the Proteobacteria. Each of the fragments (35 and 30 kb) contains a copy of 16S-23S-5S rRNA genes. A total of 37 open reading frames were detected, which corresponded to putative rRNA proteins, chaperones, and enzymes of branched-chain amino acid biosynthesis, DNA replication, protein translation, and RNA synthesis. The genome of T. princeps has a number of properties that distinguish it from the genomes of Buchnera aphidicola and Carsonella ruddii, the endosymbionts of aphids and psyllids, respectively. Among these properties are a high G+C content (57.1 mol%), the same G+C content in intergenic spaces and structural genes, and similar G+C contents of the genes encoding highly and poorly conserved proteins. The high G+C content has a substantial effect on protein composition; about one-third of the residues consist of four amino acids with high-G+C-content codons. Sequence analysis of DNA fragments containing the rRNA operon and adjacent regions from endosymbionts of several mealybug species suggested that there was a single duplication of the rRNA operon and the adjacent genes in an ancestor of the present T. princeps. Subsequently, in one mealybug lineage rpS15, one of the duplicated genes, was retained, while in another lineage it decayed. These results extend the diversity of the types of endosymbiotic associations found in plant sap-sucking insects.

  9. Hylax bahiensis Bechyné (Chrysomelidae: Eumolpinae): a New Potential Pest of Eucalyptus and Species Used for Atlantic Rainforest Restoration.

    PubMed

    Mafia, R G; da Silva, J B; Ramos, J F; Mafia, G V; Rosado-Neto, G H; Ferronatto, E M O

    2015-02-01

    Hylax bahiensis Bechyné (Coleoptera: Chrysomelidae), a new pest of forest species, including eucalyptus (hybrid Eucalyptus urophylla x Eucalyptus grandis), Joannesia princeps, Mimosa artemisiana, Croton urucurana, Croton floribundus, and Senna multijuga is recorded. The insect attack in clonal eucalyptus plantations and in forest restoration areas between 2010 and 2013 in the states of Espírito Santo, Bahia and Minas Gerais, Brasil, was observed for the first time. The outbreaks generally occurred from September to March. This new potential pest can affect the growth, productivity, and quality of the trees. We recommended monitoring this leaf-eating beetle especially during the critical period of its occurrence.

  10. Bioengineering novel floating nanoparticles for protein and drug delivery

    PubMed Central

    DasSarma, Priya; Karan, Ram; Kim, Jong-Myoung; Pecher, Wolf; DasSarma, Shiladitya

    2016-01-01

    Gas vesicle nanoparticles (GVNPs) are hollow protein nanoparticles produced by Halobacterium sp. NRC-1 which are being engineered for protein delivery. To advance the bioengineering potential of GVNPs, a strain of NRC-1 deleted for the gvpC gene (ΔgvpC) was constructed and a synthetic gene coding for Gaussia princeps luciferase was fused to an abbreviated gvpC gene on an expression plasmid. When introduced into theΔgvpC strain, an active GvpC-luciferase fusion protein bound to GVNPs resulted. These results represent both a technical improvement in the GVNP display system and its expansion for the display of active enzymes. PMID:27158595

  11. Revision of some ophiuroid records (Echinodermata: Ophiuroidea) from Argentina.

    PubMed

    Brogger, Martin I; O'Hara, Timothy D

    2015-06-12

    The taxonomy of some ophiuroids reported from off Argentina, western Antarctica and the SW Atlantic Ocean is reviewed. The species Amphilepis sanmatiensis, known only from the small holotype, is a synonym of Amphioplus lucyae. This synonymy removes the only reported endemic ophiuroid from Argentina. The species name "Ophiacantha ingrata Koehler, 1923" used for specimens from South Georgia is invalid; the specimens are likely to belong to one of two cryptic species within the O. vivipara complex. Specimens of Amphiura joubini reported from Argentina are re-identified as Amphiura princeps, and specimens of Ophiactis amator from the Antarctic Peninsula are re-identified as Ophiactis asperula.

  12. Molecular Identification of Echinococcus multilocularis Infection in Small Mammals from Northeast, Iran

    PubMed Central

    Beiromvand, Molouk; Akhlaghi, Lame; Fattahi Massom, Seyed Hossein; Meamar, Ahmad Reza; Darvish, Jamshid; Razmjou, Elham

    2013-01-01

    Background Alveolar echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus multilocularis. Many species of small mammals, including arvicolid rodents or Ochotona spp., are natural intermediate hosts of the cestode. The main aim of this study was to identify natural intermediate hosts of E. multilocularis in Chenaran County, Razavi Khorasan Province, northeastern Iran, where the prevalence of infected wild and domestic carnivores is high. Methodology/Principal Findings A program of trapping was carried out in five villages in which this cestode was reported in carnivores. The livers of 85 small mammals were investigated for the presence of E. multilocularis infection using multiplex PCR of mitochondrial genes. Infections were identified in 30 specimens: 23 Microtus transcaspicus, three Ochotona rufescens, two Mus musculus, one Crocidura gmelini, and one Apodemus witherbyi. Conclusions/Significance A range of small mammals therefore act as natural intermediate hosts for the transmission of E. multilocularis in Chenaran County, and the prevalence suggested that E. multilocularis infection is endemic in this region. The existence of the life cycle of this potentially lethal cestode in the vicinity of human habitats provides a significant risk of human infection. PMID:23875048

  13. Stem Lagomorpha and the antiquity of Glires.

    PubMed

    Asher, Robert J; Meng, Jin; Wible, John R; McKenna, Malcolm C; Rougier, Guillermo W; Dashzeveg, Demberlyn; Novacek, Michael J

    2005-02-18

    We describe several fossils referable to Gomphos elkema from deposits close to the Paleocene-Eocene boundary at Tsagan Khushu, Mongolia. Gomphos shares a suite of cranioskeletal characters with extant rabbits, hares, and pikas but retains a primitive dentition and jaw compared to its modern relatives. Phylogenetic analysis supports the position of Gomphos as a stem lagomorph and excludes Cretaceous taxa from the crown radiation of placental mammals. Our results support the hypothesis that rodents and lagomorphs radiated during the Cenozoic and diverged from other placental mammals close to the Cretaceous-Tertiary boundary.

  14. Discovery of a new hydrothermal vent based on an underwater, high-resolution geophysical survey

    NASA Astrophysics Data System (ADS)

    Nakamura, Kentaro; Toki, Tomohiro; Mochizuki, Nobutatsu; Asada, Miho; Ishibashi, Jun-ichiro; Nogi, Yoshifumi; Yoshikawa, Shuro; Miyazaki, Jun-ichi; Okino, Kyoko

    2013-04-01

    A new hydrothermal vent site in the Southern Mariana Trough has been discovered using acoustic and magnetic surveys conducted by the Japan Agency for Marine-Earth Science and Technology's (JAMSTEC) autonomous underwater vehicle (AUV), Urashima. The high-resolution magnetic survey, part of a near-bottom geophysical mapping around a previously known hydrothermal vent site, the Pika site, during the YK09-08 cruise in June-July 2009, found that a clear magnetization low extends ˜500 m north from the Pika site. Acoustic signals, suggesting hydrothermal plumes, and 10 m-scale chimney-like topographic highs were detected within this low magnetization zone by a 120 kHz side-scan sonar and a 400 kHz multibeam echo sounder. In order to confirm the seafloor sources of the geophysical signals, seafloor observations were carried out using the deep-sea manned submersible Shinkai 6500 during the YK 10-10 cruise in August 2010. This discovered a new hydrothermal vent site (12°55.30'N, 143°38.89'E; at a depth of 2922 m), which we have named the Urashima site. This hydrothermal vent site covers an area of approximately 300 m×300 m and consists of black and clear smoker chimneys, brownish-colored shimmering chimneys, and inactive chimneys. All of the fluids sampled from the Urashima and Pika sites have chlorinity greater than local ambient seawater, suggesting subseafloor phase separation or leaching from rocks in the hydrothermal reaction zone. End-member compositions of the Urashima and Pika fluids suggest that fluids from two different sources feed the two sites, even though they are located on the same knoll and separated by only ˜500 m. We demonstrate that investigations on hydrothermal vent sites located in close proximity to one another can provide important insights into subseafloor hydrothermal fluid flow, and also that, while such hydrothermal sites are difficult to detect by conventional plume survey methods, high-resolution underwater geophysical surveys provide an

  15. Telegraph Canyon Creek Channel Improvement Project, San Diego County, California; Hydraulic Model Investigation

    DTIC Science & Technology

    1988-11-01

    USAEWES (if pikae ) Hydraulics Laboratory CEWES-HS-L 6C. ADDRESS (Cty, Stat, and ZP Code) 7b. ADDRESS (Cty, State, and ZIP Code) PO Box 631 Vicksburg, MS...the model was modified to reproduce upstream channel improvements to sta 78+00 to reflect the change in location of the inlets to the box culverts from...being less than 1 mile* and the length about 10 miles; the total drainage area is about 7.5 square miles. Because climatic and drainage area

  16. Allozyme and DNA sequence comparisons of nine species of Encephalartos (Zamiaceae).

    PubMed

    van der Bank H; Wink; Vorster; Treutlein; Brand; van der Bank M; Hurter

    2001-03-01

    Phylogenetic relationships between Encephalartos altensteinii Lehmann, E. arenarius R.A. Dyer, E. horridus (Jacquin) Lehmann, E. latifrons Lehmann, E. lehmannii Lehmann, E. longifolius (Jacquin) Lehmann, E. princeps R.A. Dyer and E. trispinosus (Hooker) R.A. Dyer were studied, using E. ferox Bertoloni f. as outgroup. Three continuous and one discontinuous buffer systems were used and gene products of 14 enzyme coding loci were examined by horizontal starch gel-electrophoresis. Genetic variation was studied in a cultivated population of E. lehmannii and the average heterozygosity value for this population is 13.5%, which falls within the range reported for other cycad species. Fixed allele differences between the species studied was not found at any of the loci studied, which suggest that these species are closely related. DNA sequence analysis of rbcL and ITS 1 & 2 genes (1428 and 895 basepairs, respectively) confirmed the close genetic relationships between these taxa. According to ITS and rbcL sequences E. altensteinii and E. princeps are sibling taxa which form a sister group to E. arenarius, E. horridus, E. latifrons, E. lehmannii, E. longifolius, and E. trispinosus. The genetic distances between both groups were 0.12-0.47% for ITS and 0.08-0.16% for rbcL DNA. The results indicate recent (probably pleistocenic) speciation for this group of cycads, and the relationships are discussed with reference to affinities based on morphology and distribution.

  17. The First Finding of Six Instars of Larvae in Heteroptera and the Negative Correlation between Precipitation and Number of Individuals Collected in Sea Skaters of Halobates (Heteroptera: Gerridae)

    PubMed Central

    Harada, Tetsuo; Furuki, Takahiro; Ohoka, Wataru; Umamoto, Noritomo; Nakajo, Mitsuru; Katagiri, Chihiro

    2016-01-01

    This study, conducted during a scientific cruise, MR15-04, aims, first, to examine species and larval/adult components of Halobates (Heteroptera: Gerridae) inhabiting the tropical Indian Ocean of 4°00′ S–7°00′ S, 101°00′ E–103°00′ E and, second, to examine the correlative relationship between precipitation just before collection and the number of sea skaters collected in November and December 2015. Near Sumatra (50 km south-west), larvae and adults of four species of Halobates (Halobates germanes White, 1883; Halobates micans Eschscholtz, 1822; Halobates princeps White, 1883; undescribed species: Halobates sp.) were collected. Adults of an undescribed species had about a 5 mm long body in a gourd-like shape. One male adult specimen of H. princeps was collected. Body length, body width, and head width was measured in all specimens of Halobates. Six larval stages were detected in all three species of sea skaters as the first finding for Heteropteran insects. There was a negative correlation between amount of precipitation for 19 h before collection and the number of Halobates individuals collected by the neuston net. Death or (positive or passive) sinking by sea skaters could be due to occasional rain fall on the sea surface. PMID:27941620

  18. Binding Studies of TNF Receptor Superfamily (TNFRSF) Receptors on Intact Cells*

    PubMed Central

    Lang, Isabell; Füllsack, Simone; Wyzgol, Agnes; Fick, Andrea; Trebing, Johannes; Arana, José Antonio Carmona; Schäfer, Viktoria; Weisenberger, Daniela; Wajant, Harald

    2016-01-01

    Ligands of the tumor necrosis factor superfamily (TNFSF) interact with members of the TNF receptor superfamily (TNFRSF). TNFSF ligand-TNFRSF receptor interactions have been intensively evaluated by many groups. The affinities of TNFSF ligand-TNFRSF receptor interactions are highly dependent on the oligomerization state of the receptor, and cellular factors (e.g. actin cytoskeleton and lipid rafts) influence the assembly of ligand-receptor complexes, too. Binding studies on TNFSF ligand-TNFRSF receptor interactions were typically performed using cell-free assays with recombinant fusion proteins that contain varying numbers of TNFRSF ectodomains. It is therefore not surprising that affinities determined for an individual TNFSF ligand-TNFRSF interaction differ sometimes by several orders of magnitude and often do not reflect the ligand activity observed in cellular assays. To overcome the intrinsic limitations of cell-free binding studies and usage of recombinant receptor domains, we performed comprehensive binding studies with Gaussia princeps luciferase TNFSF ligand fusion proteins for cell-bound TNFRSF members on intact cells at 37 °C. The affinities of the TNFSF ligand G. princeps luciferase-fusion proteins ranged between 0.01 and 19 nm and offer the currently most comprehensive and best suited panel of affinities for in silico studies of ligand-receptor systems of the TNF family. PMID:26721880

  19. [Wishes for recovery on bronze--comments on a coin in honour of L. Aelius Caesar].

    PubMed

    Moog, Ferdinand Peter

    2006-01-01

    L. Aelius Caesar is a little known co-regent of Hadrian who, having already been taken ill, was elected Princeps as Hadrian's successor and died soon afterwards. The city of Mytilene in Lesbos dedicated a bronze coin for him while he was still alive. The reverse of the coin shows the arrival of Asclepios in the shape of a snake. It is certainly a reference to the mythic translation of the cult of Asclepios to Rome in the third century B. C. which introduced the worship of the healing god on the Tiber Island. The community of Mytilene that struck the coin wanted to wish the ruler, whose illness was generally known, a good recovery or even to encourage him to convalesce at the famous ancient spa of Mytilene. At the same time they wanted to make a request on their own behalf. They wanted to gain the favour of the putative successor to the ruling Princeps in order to keep or regain certain liberties for their city which have been reduced by Vespasian in his centralization of the Roman Empire.

  20. Mealybugs nested endosymbiosis: going into the ‘matryoshka’ system in Planococcus citri in depth

    PubMed Central

    2013-01-01

    Background In all branches of life there are plenty of symbiotic associations. Insects are particularly well suited to establishing intracellular symbiosis with bacteria, providing them with metabolic capabilities they lack. Essential primary endosymbionts can coexist with facultative secondary symbionts which can, eventually, establish metabolic complementation with the primary endosymbiont, becoming a co-primary. Usually, both endosymbionts maintain their cellular identity. An exception is the endosymbiosis found in mealybugs of the subfamily Pseudoccinae, such as Planococcus citri, with Moranella endobia located inside Tremblaya princeps. Results We report the genome sequencing of M. endobia str. PCVAL and the comparative genomic analyses of the genomes of strains PCVAL and PCIT of both consortium partners. A comprehensive analysis of their functional capabilities and interactions reveals their functional coupling, with many cases of metabolic and informational complementation. Using comparative genomics, we confirm that both genomes have undergone a reductive evolution, although with some unusual genomic features as a consequence of coevolving in an exceptional compartmentalized organization. Conclusions M. endobia seems to be responsible for the biosynthesis of most cellular components and energy provision, and controls most informational processes for the consortium, while T. princeps appears to be a mere factory for amino acid synthesis, and translating proteins, using the precursors provided by M. endobia. In this scenario, we propose that both entities should be considered part of a composite organism whose compartmentalized scheme (somehow) resembles a eukaryotic cell. PMID:23548081

  1. Variations in the superficial palmar arch of the hand.

    PubMed

    Bataineh, Ziad M; Habbal, Omar; Moqattash, Satei T

    2009-01-01

    Variations in the pattern of the hand blood supply are frequently encountered. Awareness and identification of such variations is crucial during hand surgery. Thirty formaline fixed hands of male and female cadavers were dissected. All arteries contributing to the superficial palmar arch (SPA) of the hand were verified. In addition to the frequently encountered types of SPA, three very rare cases were described. In the first case, the superficial branch of the radial artery passed superficial to the thenar muscles with a diameter larger than that of the ulnar artery. In addition to the common palmar digital artery to the second web space, it gave the princeps pollicis and radialis indicis arteries. In the second case, the SPA was formed by the ulnar artery and was completed by a small branch from the deep branch of the radial artery. The palmar digital artery to the ulnar side of the fifth finger and the common palmar digital artery to the fourth web space arose from a common trunk. In the third case, incomplete SPA was formed by the median artery which only gave the princeps pollicis and radialis indicis arteries, while the ulnar artery supplied the rest of the hand except the ulnar side of the third finger and the second web space which were supplied by the deep palmar arch. Therefore, sound knowledge of the pattern of the blood supply of the hand by various techniques is crucial to avoid possible complications during hand surgery.

  2. The First Finding of Six Instars of Larvae in Heteroptera and the Negative Correlation between Precipitation and Number of Individuals Collected in Sea Skaters of Halobates (Heteroptera: Gerridae).

    PubMed

    Harada, Tetsuo; Furuki, Takahiro; Ohoka, Wataru; Umamoto, Noritomo; Nakajo, Mitsuru; Katagiri, Chihiro

    2016-12-07

    This study, conducted during a scientific cruise, MR15-04, aims, first, to examine species and larval/adult components of Halobates (Heteroptera: Gerridae) inhabiting the tropical Indian Ocean of 4°00' S-7°00' S, 101°00' E-103°00' E and, second, to examine the correlative relationship between precipitation just before collection and the number of sea skaters collected in November and December 2015. Near Sumatra (50 km south-west), larvae and adults of four species of Halobates (Halobates germanes White, 1883; Halobates micans Eschscholtz, 1822; Halobates princeps White, 1883; undescribed species: Halobates sp.) were collected. Adults of an undescribed species had about a 5 mm long body in a gourd-like shape. One male adult specimen of H. princeps was collected. Body length, body width, and head width was measured in all specimens of Halobates. Six larval stages were detected in all three species of sea skaters as the first finding for Heteropteran insects. There was a negative correlation between amount of precipitation for 19 h before collection and the number of Halobates individuals collected by the neuston net. Death or (positive or passive) sinking by sea skaters could be due to occasional rain fall on the sea surface.

  3. Multiplex PCR method to discriminate Artemisia iwayomogi from other Artemisia plants.

    PubMed

    Doh, Eui Jeong; Oh, Seung-Eun

    2012-01-01

    Some plants in the genus Artemisia have been used for medicinal purposes. Among them, Artemisia iwayomogi, commonly referred to as "Haninjin," is one of the major medicinal materials used in traditional Korean medicine. By contrast, Artemisia capillaris and both Artemisia argyi and Artemisia princeps, referred to as "Injinho" and "Aeyup," respectively, are used to treat diseases different from those for which "Haninjin" is prescribed. Therefore, the development of a reliable method to differentiate each Artemisia herb is necessary. We found that a random amplified polymorphic DNA (RAPD) method can be used to efficiently discriminate a few Artemisia plants from one another. To improve the reliability of RAPD amplification, we designed primer sets based on the nucleotide sequences of RAPD products to amplify a sequence-characterized amplified region (SCAR) marker of A. iwayomogi. In addition, we designed two other primer sets to amplify SCAR markers of "Aeyup" (A. argyi and A. princeps) along with "Injinho" (A. capillaris) and Artemisia japonica, which are also traded in Korean herbal markets. Using these three primer sets, we developed a multiplex PCR method concurrently not only to discriminate A. iwayomogi from other Artemisia plants, but also to identify Artemisia plants using a single PCR process.

  4. Snow Micro-Structure Model

    SciTech Connect

    Micah Johnson, Andrew Slaughter

    2014-06-25

    PIKA is a MOOSE-based application for modeling micro-structure evolution of seasonal snow. The model will be useful for environmental, atmospheric, and climate scientists. Possible applications include application to energy balance models, ice sheet modeling, and avalanche forecasting. The model implements physics from published, peer-reviewed articles. The main purpose is to foster university and laboratory collaboration to build a larger multi-scale snow model using MOOSE. The main feature of the code is that it is implemented using the MOOSE framework, thus making features such as multiphysics coupling, adaptive mesh refinement, and parallel scalability native to the application. PIKA implements three equations: the phase-field equation for tracking the evolution of the ice-air interface within seasonal snow at the grain-scale; the heat equation for computing the temperature of both the ice and air within the snow; and the mass transport equation for monitoring the diffusion of water vapor in the pore space of the snow.

  5. Snow Micro-Structure Model

    SciTech Connect

    Micah Johnson, Andrew Slaughter

    2014-06-25

    PIKA is a MOOSE-based application for modeling micro-structure evolution of seasonal snow. The model will be useful for environmental, atmospheric, and climate scientists. Possible applications include application to energy balance models, ice sheet modeling, and avalanche forecasting. The model implements physics from published, peer-reviewed articles. The main purpose is to foster university and laboratory collaboration to build a larger multi-scale snow model using MOOSE. The main feature of the code is that it is implemented using the MOOSE framework, thus making features such as multiphysics coupling, adaptive mesh refinement, and parallel scalability native to the application. PIKA implements three equations: the phase-field equation for tracking the evolution of the ice-air interface within seasonal snow at the grain-scale; the heat equation for computing the temperature of both the ice and air within the snow; and the mass transport equation for monitoring the diffusion of water vapor in the pore space of the snow.

  6. Evolutionary Insights into IL17A in Lagomorphs

    PubMed Central

    Neves, Fabiana; Abrantes, Joana; Almeida, Tereza; Costa, Paulo P.; Esteves, Pedro J.

    2015-01-01

    In leporids, IL17A had been implicated in the host defense against extracellular pathogens, such as Francisella tularensis that infects hares and rabbits and causes the zoonotic disease tularemia. Here, we studied IL17A from five lagomorphs, European rabbit, pygmy rabbit, brush rabbit, European brown hare, and American pika. We observed that this protein is highly conserved between these species, with a similarity of 97–99% in leporids and ~88% between leporids and American pika. The exon/intron structure, N-glycosylation sites, and cysteine residues are conserved between lagomorphs. However, at codon 88, one of the interaction sites between IL17A and its receptor IL17RA, there is an Arg>Pro mutation that only occurs in European rabbit and European brown hare. This could induce critical alterations in the IL17A structure and conformation and consequently modify its function. The differences observed between leporids and humans or rodents might also represent important alterations in protein structure and function. In addition, as for other interleukins, IL17A sequences of human and European rabbit are more closely related than the sequences of human and mouse or European rabbit and mouse. This study gives further support to the hypothesis that European rabbit might be a more suitable animal model for studies on human IL17. PMID:26788019

  7. New flexible growth function and its application to the growth of small mammals.

    PubMed

    Wan, X; Zhong, W; Wang, M

    1998-01-01

    The function [formula: see text] where a is the upper asympotic weight and b, c, k are constants, is derived as a new flexible growth equation and evaluated using commonly applied growth functions such as Monomelecular, Gompertz, Logistic, Richards, France, Janoschek and Hill. Three sets of observations on growth of small mammal species (Microtus brandti and Ochotona curzoniae) are used to evaluate the fits of these functions. In addition, points of inflexion of these growth equations are also derived in this paper. The new function encompasses the Logistic and Monomolecular equation for different value of parameter b. It provides a flexible growth equation capable of describing smooth sigmoidal and diminishing returns behaviour. The success of the new equation in describing these sets of growth patterns underlines its credentials as a suitable additional growth function.

  8. High mercury concentrations reflect trophic ecology of three deep-water chondrichthyans.

    PubMed

    Newman, Michael C; Xu, Xiaoyu; Cotton, Charles F; Tom, Kyle R

    2011-05-01

    The relative contributions of proximity to mercury sources and trophic ecology to realized axial muscle mercury concentrations were explored for three deep-water chondrichthyans (Etmopterus princeps, Centroscymnus coelolepis, and Hydrolagus affinis), two species of which are harvested for human consumption. Samples were taken at three North Atlantic Ocean locations: the Azores, the Charlie Gibbs Fracture Zone, and the Bear Seamount. Despite the long distances between anthropogenic sources and the sampling locations, all species from all locations had muscle mercury concentrations exceeding the United States human health screening value of 0.3 mg/kg wet weight. Proximity to anthropogenic sources was not an obvious determinant of these elevated concentrations. Generally, mercury concentrations appeared to increase with increased dependence on benthic versus pelagic food sources (as indicated by interspecies differences in δ(13)C), and with higher position in the trophic web (as indicated by differences in δ(15)N).

  9. The Vascularized Medial Femoral Corticoperiosteal Flap for Thumb Reconstruction

    PubMed Central

    Amin, Kavit; Darhouse, Nagham; Sivakumar, Bran; Floyd, David

    2015-01-01

    Summary: We present an interesting method of shaping a vascularized medial femoral condyle (MFC) flap into a “neophalanx” for phalangeal reconstruction. Our patient presented with limited strength and function secondary to fracture nonunion of the proximal phalanx of the dominant thumb. Following excision of the pseudarthrosis, an MFC corticoperiosteal flap was harvested, sculpted into a prism shape and inset. The superomedial genicular pedicle was anastomosed to the princeps pollicis artery and a cephalic tributary. On follow-up, new bone growth was seen on radiographs and the patient had substantially improved function, with full metacarpophalangeal extension, a Kapandji score of 9, and a markedly reduced Disabilities of the Arm, Shoulder and Hand score of 2.68. The MFC flap is useful for reconstruction of bony defects, with minimal donor morbidity. This versatile vascularized flap can be crafted to requisite shapes and is useful for small defects in the hand, including phalangeal reconstruction. PMID:26495205

  10. First record of a living species of the genus Janulum (Class Demospongiae)
    in the Southern Hemisphere.

    PubMed

    Kelly, Michelle; Erpenbeck, Dirk; Morrow, Christine; Soest, Rob Van

    2015-06-29

    A new species of the enigmatic sponge genus Janulum de Laubenfels, 1936 was discovered recently on the Louisville Seamount Chain, in International Waters to the east of New Zealand; two small specimens were found encrusting the interstices of the stony coral Solenosmilia variabilis Duncan at a depth of 1200-1600 m. Janulum imago sp. nov., is described and compared with the genus type J. spinispiculum (Carter, 1876) from the North Atlantic. Janulum was also recorded from the Late Eocene Oamaru Diatomite of southern New Zealand in 1892, but was misidentified as genus Plocamia Schmidt (Order Poecilosclerida Topsent, Family Microcionidae Carter). Fossil species Janulum princeps sp. nov. is also described herein and represents the first record of this North Atlantic-Arctic Ocean genus in the Southern Hemisphere. The validity of J. filholi (Topsent, 1890), the second and only other North Atlantic species currently assigned to Janulum, is considered in the context of J. spinispiculum and the new species J. imago sp. nov.

  11. A study of the superficial palmar arteries using the Doppler Ultrasonic Flowmeter.

    PubMed Central

    Al-Turk, M; Metcalf, W K

    1984-01-01

    The pattern of the superficial arteries of the hand has been studied utilising the Doppler Flowmeter technique. The superficial arteries of the hand formed several diversified patterns that permitted classification into well defined categories. The arcus palmaris superficialis was complete in 84% of the hands and incomplete in 16%. The arteria digitalis palmaris communis primus took origin from the arch in 94% and from the arterial radialis indicis in 6% of the hands. The arteria princeps pollicis and radialis indicis were quite variable in their origin and frequently differed from the normal textbook description. In 52% of the subjects, the arterial patterns in the right and left hand were different with respect to one or more arteries, while they were identical in 48% of the subjects. It would be unwise to base anything more than tentative conclusions on the data so far accumulated, because of the small population used in this project and the absence of similar studies in the literature. PMID:6706837

  12. [Mindfulness-Based Cognitive Therapy (MBCT) program with workers in an industrial setting: a pilot study].

    PubMed

    Strub, Lionel; Tarquinio, Cyril

    2013-01-01

    The article describes the implementation of a pilot program in the tradition of secondary prevention interventions aimed at reducing the severity of stress symptom. Developed from the MBCT protocol, designed to prevent depressive relapse, its specificity lies in the adaptation of its teaching materials resting on the mindfulness meditation-cognition-psycho-education triptych. The transposition of the princeps model has been the subject of a controlled and randomized experimental trial performed on a non-clinical population working in an industrial environment to assess the effect of the aforesaid program on stress and associated symptoms. The outcomes suggest preliminary contributions as for the benefits generated on the psychic health of a group of workers.

  13. [Discovering the authentic Hildegard. Comments on the only in Florance 'Physica' handwritten texts].

    PubMed

    Vollmann, Benedikt Konrad

    2003-01-01

    The recently discovered ms. of Hildegard's, Physica' (Florence, B. Med.-Laurenz. Ashburnh. 1323) contains much more text than the Migne edition, based on Paris, BN.lat. 6952, does. Did the Florence ms. add or the Paris ms. omit? A comparison of all extant mss. and the edition princeps of 1533 reveals that the corpus of items and their order remain essentially the same, whereas the number of recipes and applications is in permanent decrease. We also observe an increasing reduction of explanatory remarks unique to Hildegard's medical doctrine. The more copious text of the Florence ms. must, therefore, be regarded as authentic, and it should be made the base of a future edition of the 'Physica'.

  14. [What are the links between sport activities and eating disorders?].

    PubMed

    Afflelou, Sabine; Duclos, Martine; Simon, Serge

    2004-12-18

    SPORT, CAUSE OR CONSEQUENCE?: There are arguments in favour of a "princeps" disorder that would orientate young anorexic girls towards certain sports and exercises, others, conversely, underline the propensity of certain sports to lead to the onset of eating disorders. AN EXAMPLE: The description of a clinical case evokes the complexity of this relationship demonstrating that intensive exercise training may promote such problems but will also limit the severity of anorexia nervosa. FROM A PRACTICAL POINT OF VIEW: We should give up the global concept of "sport" and define "exercise training" the intensity, the exclusiveness and the intrinsic body weight constraints of which are recognised as risk factors, together with a more fragile population (adolescents, females). Based on these data, prevention strategies should be applied in particularly exposed institutions.

  15. Distribution of odonates (dragonflies and damselflies) in the Indiana Dunes National Lakeshore and nearby lands

    USGS Publications Warehouse

    Smolka, George E.; Stewart, Paul M.; Swinford, Thomas O.

    1999-01-01

    From 1993 to 1997, 60 species of Anisoptera (dragonflies) and Zygoptera (damselflies) were found in Lake and Porter Counties, Indiana, including Indiana Dunes National Lakeshore, in contrast to 34 species that were recorded historically from this region. We added 17 new species to Lake County's odonate records and 39 new species to the 5 previously recorded in Porter County. Several regionally rare species were collected: Aeshna clepsydra, Enallagma cyathigerum, and Leucorrhina frigida. Nine species listed in the historical records were missing from our collections: Hetaerina americana, Calopteryx aequabilis, Nehalennia irene, Arigomphus furcifer, Argia fumipennis violacea, Gomphus spicatus, Epitheca princeps, Libellula exusta, and Sympetrum semicinctum. These nine species have either declined in the area or they may be found in other habitats after further study. Because few odonate surveys were conducted in northwest Indiana in the past, a poor baseline exists for comparisons of temporal trends in odonate diversity.

  16. Horizontal gene transfer from diverse bacteria to an insect genome enables a tripartite nested mealybug symbiosis.

    PubMed

    Husnik, Filip; Nikoh, Naruo; Koga, Ryuichi; Ross, Laura; Duncan, Rebecca P; Fujie, Manabu; Tanaka, Makiko; Satoh, Nori; Bachtrog, Doris; Wilson, Alex C C; von Dohlen, Carol D; Fukatsu, Takema; McCutcheon, John P

    2013-06-20

    The smallest reported bacterial genome belongs to Tremblaya princeps, a symbiont of Planococcus citri mealybugs (PCIT). Tremblaya PCIT not only has a 139 kb genome, but possesses its own bacterial endosymbiont, Moranella endobia. Genome and transcriptome sequencing, including genome sequencing from a Tremblaya lineage lacking intracellular bacteria, reveals that the extreme genomic degeneracy of Tremblaya PCIT likely resulted from acquiring Moranella as an endosymbiont. In addition, at least 22 expressed horizontally transferred genes from multiple diverse bacteria to the mealybug genome likely complement missing symbiont genes. However, none of these horizontally transferred genes are from Tremblaya, showing that genome reduction in this symbiont has not been enabled by gene transfer to the host nucleus. Our results thus indicate that the functioning of this three-way symbiosis is dependent on genes from at least six lineages of organisms and reveal a path to intimate endosymbiosis distinct from that followed by organelles.

  17. Analysis of Dragonfly Take-off Mechanism: Initial Impulse Generated by Aerodynamic Forces

    NASA Astrophysics Data System (ADS)

    Zhu, Ruijie; Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Flow Simulation Research Team

    2013-11-01

    Take-off is a critical part of insect flight due to not only that every single flight initiates from take-off, but also that the take-off period, despite its short duration, accounts for a relatively large fraction of the total energy consumption. Thus, studying the mechanism of insect take-off will help to improve the design of Micro Air Vehicles (MAVs) in two major properties, the success rate and the energy efficiency of take-off. In this work, we study 20 cases in which dragonflies (species including Pachydiplax longipennis, Epitheca Cynosura, Epitheca princeps etc.) take off from designed platform. By high-speed photogrammetry, 3-d reconstruction and numerical simulation, we explore how dragonflies coordinate different body parts to help take-off. We evaluate how aerodynamic forces generated by wing flapping create the initial impulse, and how these forces help save energy consumption. Supported by NSF CBET-1343154.

  18. François Tissard and his 1508 edition of the Hippocratic Oath.

    PubMed

    Rütten, Thomas

    2005-01-01

    A few years ago, a Greek text of the Hippocratic Oath (textus receptus) with an interlinear translation into Latin was (re)discovered in a book printed in 1508 in Paris. Its spiritus rector is François Tissard. This paper examines the nature of both the Greek and Latin versions of the Oath text and the rationale of including them in a book which contains an eclectic assemblage of texts in Greek, Latin and Hebrew. The paper also discusses the intellectual background of Tissard and his publishing programme, set up by Gilles de Gourmont. It addresses the social, political, pedagogical and religious implications of publishing a bilingual version of the Hippocratic Oath in 1508 in Paris, i.e. for the first time in the history of printing, and attempts to accommodate this "editio princeps" (at least for the present) within the textual history of the Hippocratic Oath.

  19. Microsatellite DNA markers for assessing phylogeographic and population structure in Preble's meadow jumping mice (Zapus hudsonius preblei) and cross-amplification among neighbouring taxa

    USGS Publications Warehouse

    King, T.L.; Eackles, M.S.; Young, C.

    2006-01-01

    We document the isolation and characterization of 14 tetranucleotide microsatellite DNA markers in Preble's meadow jumping mouse (Zapus hudsonius preblei). The identified markers displayed moderate levels of allelic diversity (averaging 4.9 alleles per locus) and heterozygosity (averaging 55.1%). Genotypic and allelic frequencies in a collection of 30 individuals conformed to Hardy-Weinberg equilibrium expectations and indicated no linkage disequilibrium. High levels of cross-amplification (95% overall) among neighbouring subspecies and two congeners (Zapus princeps and Zapus trinotatus) were observed. Multilocus genotypes resulting from these markers appear to provide ample genetic diversity for studies assessing individual- and population-level ecological interactions within Z. h. preblei and evolutionary relationships among neighbouring subspecies (Z. h. campestris, Z. h. intermedius, Z. h. pallidus and Z. h. luteus). ?? 2006 The Authors.

  20. A new humanized in vivo model of KIT D816V+ advanced systemic mastocytosis monitored using a secreted luciferase

    PubMed Central

    Bibi, Siham; Zhang, Yanyan; Hugonin, Caroline; Mangean, Mallorie Depond; He, Liang; Wedeh, Ghaith; Launay, Jean-Marie; Van Rijn, Sjoerd; Würdinger, Thomas; Louache, Fawzia; Arock, Michel

    2016-01-01

    Systemic mastocytosis are rare neoplasms characterized by accumulation of mast cells in at least one internal organ. The majority of systemic mastocytosis patients carry KIT D816V mutation, which activates constitutively the KIT receptor. Patient with advanced forms of systemic mastocytosis, such as aggressive systemic mastocytosis or mast cell leukemia, are poorly treated to date. Unfortunately, the lack of in vivo models reflecting KIT D816V+ advanced disease hampers pathophysiological studies and preclinical development of new therapies for such patients. Here, we describe a new in vivo model of KIT D816V+ advanced systemic mastocytosis developed by transplantation of the human ROSAKIT D816V-Gluc mast cell line in NOD-SCID IL-2R g−/− mice, using Gaussia princeps luciferase as a reporter. Intravenous injection of ROSAKIT D816V-Gluc cells led, in 4 weeks, to engraftment in all injected primary recipient mice. Engrafted cells were found at high levels in bone marrow, and at lower levels in spleen, liver and peripheral blood. Disease progression was easily monitored by repeated quantification of Gaussia princeps luciferase activity in peripheral blood. This quantification evidenced a linear relationship between the number of cells injected and the neoplastic mast cell burden in mice. Interestingly, the secondary transplantation of ROSAKIT D816V-Gluc cells increased their engraftment capability. To conclude, this new in vivo model mimics at the best the features of human KIT D816V+ advanced systemic mastocytosis. In addition, it is a unique and convenient tool to study the kinetics of the disease and the potential in vivo activity of new drugs targeting neoplastic mast cells. PMID:27783996

  1. A new humanized in vivo model of KIT D816V+ advanced systemic mastocytosis monitored using a secreted luciferase.

    PubMed

    Bibi, Siham; Zhang, Yanyan; Hugonin, Caroline; Mangean, Mallorie Depond; He, Liang; Wedeh, Ghaith; Launay, Jean-Marie; Van Rijn, Sjoerd; Würdinger, Thomas; Louache, Fawzia; Arock, Michel

    2016-12-13

    Systemic mastocytosis are rare neoplasms characterized by accumulation of mast cells in at least one internal organ. The majority of systemic mastocytosis patients carry KIT D816V mutation, which activates constitutively the KIT receptor. Patient with advanced forms of systemic mastocytosis, such as aggressive systemic mastocytosis or mast cell leukemia, are poorly treated to date. Unfortunately, the lack of in vivo models reflecting KIT D816V+ advanced disease hampers pathophysiological studies and preclinical development of new therapies for such patients. Here, we describe a new in vivo model of KIT D816V+ advanced systemic mastocytosis developed by transplantation of the human ROSAKIT D816V-Gluc mast cell line in NOD-SCID IL-2R γ-/- mice, using Gaussia princeps luciferase as a reporter. Intravenous injection of ROSAKIT D816V-Gluc cells led, in 4 weeks, to engraftment in all injected primary recipient mice. Engrafted cells were found at high levels in bone marrow, and at lower levels in spleen, liver and peripheral blood. Disease progression was easily monitored by repeated quantification of Gaussia princeps luciferase activity in peripheral blood. This quantification evidenced a linear relationship between the number of cells injected and the neoplastic mast cell burden in mice. Interestingly, the secondary transplantation of ROSAKIT D816V-Gluc cells increased their engraftment capability. To conclude, this new in vivo model mimics at the best the features of human KIT D816V+ advanced systemic mastocytosis. In addition, it is a unique and convenient tool to study the kinetics of the disease and the potential in vivo activity of new drugs targeting neoplastic mast cells.

  2. Evolutionary relationships among primary endosymbionts of the mealybug subfamily phenacoccinae (hemiptera: Coccoidea: Pseudococcidae).

    PubMed

    Gruwell, Matthew E; Hardy, Nate B; Gullan, Penny J; Dittmar, Katharina

    2010-11-01

    Mealybugs (Coccoidea: Pseudococcidae) are sap-sucking plant parasites that harbor bacterial endosymbionts within specialized organs. Previous studies have identified two subfamilies, Pseudococcinae and Phenacoccinae, within mealybugs and determined the primary endosymbionts (P-endosymbionts) of the Pseudococcinae to be Betaproteobacteria ("Candidatus Tremblaya princeps") containing Gammaproteobacteria secondary symbionts. Here, the P-endosymbionts of phenacoccine mealybugs are characterized based on 16S rRNA from the bacteria of 20 species of phenacoccine mealybugs and four outgroup Puto species (Coccoidea: Putoidae) and aligned to more than 100 published 16S rRNA sequences from symbiotic and free-living bacteria. Phylogenetic analyses recovered three separate lineages of bacteria from the Phenacoccinae, and these are considered to be the P-endosymbionts of their respective mealybug hosts, with those from (i) the mealybug genus Rastrococcus belonging to the Bacteroidetes, (ii) the subterranean mealybugs, tribe Rhizoecini, also within Bacteroidetes, in a clade sister to cockroach endosymbionts (Blattabacterium), and (iii) the remaining Phenacoccinae within the Betaproteobacteria, forming a well-supported sister group to "Candidatus Tremblaya princeps." Names are proposed for two strongly supported lineages: "Candidatus Brownia rhizoecola" for P-endosymbionts of Rhizoecini and "Candidatus Tremblaya phenacola" for P-endosymbionts of Phenacoccinae excluding Rastrococcus and Rhizoecini. Rates of nucleotide substitution among lineages of Tremblaya were inferred to be significantly faster than those of free-living Betaproteobacteria. Analyses also recovered a clade of Gammaproteobacteria, sister to the P-endosymbiont lineage of aphids ("Candidatus Buchnera aphidicola"), containing the endosymbionts of Putoidae, the secondary endosymbionts of pseudococcine mealybugs, and the endosymbionts of several other insect groups.

  3. Secondary (gamma-Proteobacteria) endosymbionts infect the primary (beta-Proteobacteria) endosymbionts of mealybugs multiple times and coevolve with their hosts.

    PubMed

    Thao, MyLo Ly; Gullan, Penny J; Baumann, Paul

    2002-07-01

    Mealybugs (Hemiptera, Coccoidea, Pseudococcidae) are plant sap-sucking insects that have within their body cavities specialized cells containing prokaryotic primary endosymbionts (P-endosymbionts). The P-endosymbionts have the unusual property of containing within their cytoplasm prokaryotic secondary endosymbionts (S-endosymbionts) [C. D. von Dohlen, S. Kohler, S. T. Alsop, and W. R. McManus, Nature (London) 412:433-436, 2001]. Four-kilobase fragments containing 16S-23S ribosomal DNA (rDNA) were obtained from the P-endosymbionts of 22 mealybug species and the S-endosymbionts of 12 representative species. Phylogenetic analyses of the P-endosymbionts indicated that they have a monophyletic origin and are members of the beta-subdivision of the Proteobacteria; these organisms were subdivided into five different clusters. The S-endosymbionts were members of the gamma-subdivision of the Proteobacteria and were grouped into clusters similar to those observed with the P-endosymbionts. The S-endosymbiont clusters were distinct from each other and from other insect-associated bacteria. The similarity of the clusters formed by the P- and S-endosymbionts suggests that the P-endosymbionts of mealybugs were infected multiple times with different precursors of the S-endosymbionts and once the association was established, the P- and S-endosymbionts were transmitted together. The lineage consisting of the P-endosymbionts of mealybugs was given the designation "Candidatus Tremblaya" gen. nov., with a single species, "Candidatus Tremblaya princeps" sp. nov. The results of phylogenetic analyses of mitochondrial DNA fragments encoding cytochrome oxidase subunits I and II from four representative mealybug species were in agreement with the results of 16S-23S rDNA analyses, suggesting that relationships among strains of "Candidatus T. princeps" are useful in inferring the phylogeny of their mealybug hosts.

  4. An improved genetic system for bioengineering buoyant gas vesicle nanoparticles from Haloarchaea.

    PubMed

    DasSarma, Shiladitya; Karan, Ram; DasSarma, Priya; Barnes, Susan; Ekulona, Folasade; Smith, Barbara

    2013-12-21

    Gas vesicles are hollow, buoyant organelles bounded by a thin and extremely stable protein membrane. They are coded by a cluster of gvp genes in the halophilic archaeon, Halobacterium sp. NRC-1. Using an expression vector containing the entire gvp gene cluster, gas vesicle nanoparticles (GVNPs) have been successfully bioengineered for antigen display by constructing gene fusions between the gvpC gene and coding sequences from bacterial and viral pathogens. To improve and streamline the genetic system for bioengineering of GVNPs, we first constructed a strain of Halobacterium sp. NRC-1 deleted solely for the gvpC gene. The deleted strain contained smaller, more spindle-shaped nanoparticles observable by transmission electron microscopy, confirming a shape-determining role for GvpC in gas vesicle biogenesis. Next, we constructed expression plasmids containing N-terminal coding portions or the complete gvpC gene. After introducing the expression plasmids into the Halobacterium sp. NRC-1 ΔgvpC strain, GvpC protein and variants were localized to the GVNPs by Western blotting analysis and their effects on increasing the size and shape of nanoparticles established by electron microscopy. Finally, a synthetic gene coding for Gaussia princeps luciferase was fused to the gvpC gene fragments on expression plasmids, resulting in an enzymatically active GvpC-luciferase fusion protein bound to the buoyant nanoparticles from Halobacterium. GvpC protein and its N-terminal fragments expressed from plasmid constructs complemented a Halobacterium sp. NRC-1 ΔgvpC strain and bound to buoyant GVNPs. Fusion of the luciferase reporter gene from Gaussia princeps to the gvpC gene derivatives in expression plasmids produced GVNPs with enzymatically active luciferase bound. These results establish a significantly improved genetic system for displaying foreign proteins on Halobacterium gas vesicles and extend the bioengineering potential of these novel nanoparticles to catalytically active

  5. An improved genetic system for bioengineering buoyant gas vesicle nanoparticles from Haloarchaea

    PubMed Central

    2013-01-01

    Background Gas vesicles are hollow, buoyant organelles bounded by a thin and extremely stable protein membrane. They are coded by a cluster of gvp genes in the halophilic archaeon, Halobacterium sp. NRC-1. Using an expression vector containing the entire gvp gene cluster, gas vesicle nanoparticles (GVNPs) have been successfully bioengineered for antigen display by constructing gene fusions between the gvpC gene and coding sequences from bacterial and viral pathogens. Results To improve and streamline the genetic system for bioengineering of GVNPs, we first constructed a strain of Halobacterium sp. NRC-1 deleted solely for the gvpC gene. The deleted strain contained smaller, more spindle-shaped nanoparticles observable by transmission electron microscopy, confirming a shape-determining role for GvpC in gas vesicle biogenesis. Next, we constructed expression plasmids containing N-terminal coding portions or the complete gvpC gene. After introducing the expression plasmids into the Halobacterium sp. NRC-1 ΔgvpC strain, GvpC protein and variants were localized to the GVNPs by Western blotting analysis and their effects on increasing the size and shape of nanoparticles established by electron microscopy. Finally, a synthetic gene coding for Gaussia princeps luciferase was fused to the gvpC gene fragments on expression plasmids, resulting in an enzymatically active GvpC-luciferase fusion protein bound to the buoyant nanoparticles from Halobacterium. Conclusion GvpC protein and its N-terminal fragments expressed from plasmid constructs complemented a Halobacterium sp. NRC-1 ΔgvpC strain and bound to buoyant GVNPs. Fusion of the luciferase reporter gene from Gaussia princeps to the gvpC gene derivatives in expression plasmids produced GVNPs with enzymatically active luciferase bound. These results establish a significantly improved genetic system for displaying foreign proteins on Halobacterium gas vesicles and extend the bioengineering potential of these novel

  6. Aminoglycoside-induced damage in the statocyst of the longfin inshore squid, Doryteuthis pealeii.

    PubMed

    Scharr, Alexandra L; Mooney, T Aran; Schweizer, Felix E; Ketten, Darlene R

    2014-08-01

    Squid are a significant component of the marine biomass and are a long-established model organism in experimental neurophysiology. The squid statocyst senses linear and angular acceleration and is the best candidate for mediating squid auditory responses, but its physiology and morphology are rarely studied. The statocyst contains mechano-sensitive hair cells that resemble hair cells in the vestibular and auditory systems of other animals. We examined whether squid statocyst hair cells are sensitive to aminoglycosides, a group of antibiotics that are ototoxic in fish, birds, and mammals. To assess aminoglycoside-induced damage, we used immunofluorescent methods to image the major cell types in the statocyst of longfin squid (Doryteuthis pealeii). Statocysts of live, anesthetized squid were injected with either a buffered saline solution or neomycin at concentrations ranging from 0.05 to 3.0 mmol l(-1). The statocyst hair cells of the macula statica princeps were examined 5 h post-treatment. Anti-acetylated tubulin staining showed no morphological differences between the hair cells of saline-injected and non-injected statocysts. The hair cell bundles of the macula statica princeps in aminoglycoside-injected statocysts were either missing or damaged, with the amount of damage being dose-dependent. The proportion of missing hair cells did not increase at the same rate as damaged cells, suggesting that neomycin treatment affects hair cells in a nonlethal manner. These experiments provide a reliable method for imaging squid hair cells. Further, aminoglycosides can be used to induce hair cell damage in a primary sensory area of the statocyst of squid. Such results support further studies on loss of hearing and balance in squid.

  7. Detection of diverse novel astroviruses from small mammals in China.

    PubMed

    Hu, Ben; Chmura, Aleksei A; Li, Jialu; Zhu, Guangjian; Desmond, James S; Zhang, Yunzhi; Zhang, Wei; Epstein, Jonathan H; Daszak, Peter; Shi, Zhengli

    2014-11-01

    Astroviruses infect humans and many animal species and cause gastroenteritis. To extensively understand the distribution and genetic diversity of astrovirus in small mammals, we tested 968 anal swabs from 39 animal species, most of which were bats and rodents. We detected diverse astroviruses in 10 bat species, including known bat astroviruses and a large number of novel viruses. Meanwhile, novel groups of astroviruses were identified in three wild rodent species and a remarkably high genetic diversity of astrovirus was revealed in Eothenomys cachinus. We detected astroviruses in captive-bred porcupines and a nearly full-length genome sequence was determined for one strain. Phylogenetic analysis of the complete ORF2 sequence suggested that this strain may share a common ancestor with porcine astrovirus type 2. Moreover, to our knowledge, this study reports the first discovery of astroviruses in shrews and pikas. Our results provide new insights for understanding these small mammals as natural reservoirs of astroviruses.

  8. [A NATURAL PLAGUE FOCUS. IN GORNYI ALTAI: FORMATION, DEVELOPMENT, AND FUNCTIONING].

    PubMed

    Korzun, V M; Balakhoiov, S V; Chpanin, E V; Denisov, A V; Mikhailov, E P; Mischenko, A J; Yarygina, M B; Rozhdestvensky, E N; Fomina, L A

    2016-01-01

    The paper gives the results of analyzing the data of long-term studies of the natural focal pattern of plague in the Gornyi Altai natural focus. It describes a wide range of biological processes occurring in the focus and shows the most important patterns of its functioning as a complex multilevel ecological system. The key features of the formation of the focus have been revealed. The plague focus in South-Western Altai has formed relatively, recently, about half a century ago, then it has intensively developed and its enzootic area and the activity of epizootic manifestations have considerably increased. This process is due to the space-time transformations of the basic ecological and population characteristics of Pallas' pika (Ochotoma pallasi), the principal vector of the pathogen of plague and fleas parasitizing the mammal, which is in turn related to the aridization of mountain steppes in South-Western Altai.

  9. Draft genome sequence of the Tibetan antelope.

    PubMed

    Ge, Ri-Li; Cai, Qingle; Shen, Yong-Yi; San, A; Ma, Lan; Zhang, Yong; Yi, Xin; Chen, Yan; Yang, Lingfeng; Huang, Ying; He, Rongjun; Hui, Yuanyuan; Hao, Meirong; Li, Yue; Wang, Bo; Ou, Xiaohua; Xu, Jiaohui; Zhang, Yongfen; Wu, Kui; Geng, Chunyu; Zhou, Weiping; Zhou, Taicheng; Irwin, David M; Yang, Yingzhong; Ying, Liu; Bao, Haihua; Kim, Jaebum; Larkin, Denis M; Ma, Jian; Lewin, Harris A; Xing, Jinchuan; Platt, Roy N; Ray, David A; Auvil, Loretta; Capitanu, Boris; Zhang, Xiufeng; Zhang, Guojie; Murphy, Robert W; Wang, Jun; Zhang, Ya-Ping; Wang, Jian

    2013-01-01

    The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission. Both the highland American pika, and the Tibetan antelope have signals of positive selection for genes involved in DNA repair and the production of ATPase. Genes associated with hypoxia seem to have experienced convergent evolution. Thus, our study suggests that common genetic mechanisms might have been utilized to enable high-altitude adaptation.

  10. Radiometric and geometric analysis of hyperspectral imagery acquired from an unmanned aerial vehicle

    SciTech Connect

    Hruska, Ryan; Mitchell, Jessica; Anderson, Matthew; Glenn, Nancy F.

    2012-09-17

    During the summer of 2010, an Unmanned Aerial Vehicle (UAV) hyperspectral in-flight calibration and characterization experiment of the Resonon PIKA II imaging spectrometer was conducted at the U.S. Department of Energy’s Idaho National Laboratory (INL) UAV Research Park. The purpose of the experiment was to validate the radiometric calibration of the spectrometer and determine the georegistration accuracy achievable from the on-board global positioning system (GPS) and inertial navigation sensors (INS) under operational conditions. In order for low-cost hyperspectral systems to compete with larger systems flown on manned aircraft, they must be able to collect data suitable for quantitative scientific analysis. The results of the in-flight calibration experiment indicate an absolute average agreement of 96.3%, 93.7% and 85.7% for calibration tarps of 56%, 24%, and 2.5% reflectivity, respectively. The achieved planimetric accuracy was 4.6 meters (based on RMSE).

  11. Draft genome sequence of the Tibetan antelope

    PubMed Central

    Ge, Ri-Li; Cai, Qingle; Shen, Yong-Yi; San, A; Ma, Lan; Zhang, Yong; Yi, Xin; Chen, Yan; Yang, Lingfeng; Huang, Ying; He, Rongjun; Hui, Yuanyuan; Hao, Meirong; Li, Yue; Wang, Bo; Ou, Xiaohua; Xu, Jiaohui; Zhang, Yongfen; Wu, Kui; Geng, Chunyu; Zhou, Weiping; Zhou, Taicheng; Irwin, David M.; Yang, Yingzhong; Ying, Liu; Bao, Haihua; Kim, Jaebum; Larkin, Denis M.; Ma, Jian; Lewin, Harris A.; Xing, Jinchuan; Platt, Roy N.; Ray, David A.; Auvil, Loretta; Capitanu, Boris; Zhang, Xiufeng; Zhang, Guojie; Murphy, Robert W.; Wang, Jun; Zhang, Ya-Ping; Wang, Jian

    2013-01-01

    The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission. Both the highland American pika, and the Tibetan antelope have signals of positive selection for genes involved in DNA repair and the production of ATPase. Genes associated with hypoxia seem to have experienced convergent evolution. Thus, our study suggests that common genetic mechanisms might have been utilized to enable high-altitude adaptation. PMID:23673643

  12. [Analysis of formation causes of grassland degradation in Maduo County in the source region of Yellow River].

    PubMed

    Bai, Wanqi; Zhang, Yili; Xie, Gaodi; Shen, Zhenxi

    2002-07-01

    Natural and artificial factors of grassland degradation in Maduo County in source region of Yellow River were analyzed in this paper. The results showed that overgrazing was the major reason for grassland degradation. Compared with historical average, annual temperature and precipitation in Maduo had an obvious rise since the end of 1980s. Temperature rise concentrated in winter, and precipitation rise concentrated in spring and summer. Therefore, the change in water and heat condition was advantageous to grass growth there. Maduo was a county totally dependent on stock raising, and enlarging livestock population was the only choice for economic development. Together with the pressure of population growth and local Tibetan's traditional value, the number of livestock had been increased continuously, and finally reached summit in the end of 1970s. Since then, the grassland had been kept in the state of overgrazing and degradation, which also created favorable condition for the invasion of pikas, and thus sped up the process of degradation.

  13. Novel and diverse integron integrase genes and integron-like gene cassettes are prevalent in deep-sea hydrothermal vents.

    PubMed

    Elsaied, Hosam; Stokes, H W; Nakamura, Takamichi; Kitamura, Keiko; Fuse, Hiroyuki; Maruyama, Akihiko

    2007-09-01

    The lack of information about mobile DNA in deep-sea hydrothermal vents limits our understanding of the phylogenetic diversity of the mobile genome of bacteria in these environments. We used culture-independent techniques to explore the diversity of the integron/mobile gene cassette system in a variety of hydrothermal vent communities. Three samples, which included two different hydrothermal vent fluids and a mussel species that contained essentially monophyletic sulfur-oxidizing bacterial endosymbionts, were collected from Suiyo Seamount, Izu-Bonin, Japan, and Pika site, Mariana arc. First, using degenerate polymerase chain reaction (PCR) primers, we amplified integron integrase genes from metagenomic DNA from each sample. From vent fluids, we discovered 74 new integrase genes that were classified into 11 previously undescribed integron classes. One integrase gene was recorded in the mussel symbiont and was phylogenetically distant from those recovered from vent fluids. Second, using PCR primers targeting the gene cassette recombination site (59-be), we amplified and subsequently identified 60 diverse gene cassettes. In multicassette amplicons, a total of 13 59-be sites were identified. Most of these sites displayed features that were atypical of the features previously well conserved in this family. The Suiyo vent fluid was characterized by gene cassette open reading frames (ORFs) that had significant homologies with transferases, DNA-binding proteins and metal transporter proteins, while the majority of Pika vent fluid gene cassettes contained novel ORFs with no identifiable homologues in databases. The symbiont gene cassette ORFs were found to be matched with DNA repair proteins, methionine aminopeptidase, aminopeptidase N, O-sialoglycoprotein endopeptidase and glutamate synthase, which are proteins expected to play a role in animal/symbiont metabolism. The success of this study indicates that the integron/gene cassette system is common in deep-sea hydrothermal

  14. The plateau zokors' learning and memory ability is related to the high expression levels of foxP2 in the brain.

    PubMed

    Ma, Ben-Yuan; Wei, Lian; Sun, Sheng-Zhen; Wang, Duo-Wei; Wei, Deng-Bang

    2014-04-25

    Plateau zokor (Myospalax baileyi) is a subterranean mammal. Plateau zokor has high learning and memory ability, and can determine the location of blocking obstacles in their tunnels. Forkhead box p2 (FOXP2) is a transcription factor implicated in the neural control of orofacial coordination and sensory-motor integration, particularly with respect to learning, memory and vocalization. To explore the association of foxP2 with the high learning and memory ability of plateau zokor, the cDNA of foxP2 of plateau zokor was sequenced; by using plateau pika as control, the expression levels of foxP2 mRNA and FOXP2 protein in brain of plateau zokor were determined by real-time PCR and Western blot, respectively; and the location of FOXP2 protein in the brain of plateau zokor was determined by immunohistochemistry. The result showed that the cDNA sequence of plateau zokor foxP2 was similar to that of other mammals and the amino acid sequences showed a relatively high degree of conservation, with the exception of two particular amino acid substitutions [a Gln (Q)-to-His (H) change at position 231 and a Ser (S)-to-Ile (I) change at position 235]. Higher expression levels of foxP2 mRNA (3-fold higher) and FOXP2 protein (>2-fold higher) were detected in plateau zokor brain relative to plateau pika brain. In plateau zokor brain, FOXP2 protein was highly expressed in the cerebral cortex, thalamus and the striatum (a basal ganglia brain region). The results suggest that the high learning and memory ability of plateau zokor is related to the high expression levels of foxP2 in the brain.

  15. Nidicolous ticks of small mammals in Anaplasma phagocytophilum-enzootic sites in northern California

    PubMed Central

    Foley, Janet; Rejmanek, Daniel; Fleer, Katryna; Nieto, Nathan

    2011-01-01

    Ixodes spp. tick-borne zoonotic diseases are present across the Holarctic in humans, domestic animals, and wildlife. Small mammals are reservoirs for the rickettsial pathogen Anaplasma phagocytophilum and tick vectors may include catholic-feeding bridge vectors as well as host-specialist or nidicolous ticks. Far western North American communities in which A. phagocytophilum is maintained are complex ecologically, with multiple reservoir host and tick species, multiple strains of the bacterial pathogen A. phagocytophilum and differences in dynamics of hosts and vectors across heterogeneous landscapes. We evaluated sites in northern California in order to identify primarily nidicolous ticks and the hosts they infest. A total of 667 ticks was found in 11 study sites, including 288 on flags and 379 attached to small mammals. Larvae were over-represented among attached ticks and adults on flags. The most abundant species was I. pacificus. Two-hundred fourteen nidicolous ticks were found, most abundantly I. angustus and I. spinipalpis. All adult I. ochotonae, I. auritulus, I. angustus, I. jellisoni, and I. woodi were female, while the male:female ratio of I. spinipalpis was 1.2:1 and 1:1 for I. pacificus. The greatest number of ticks was obtained from Tamias ochrogenys, Peromyscus spp., and Neotoma fuscipes. Of 234 small mammal individuals that were infested with Ixodes spp., only 81 (34.6%) were infested with I. pacificus. The remaining infested small mammals hosted nidicolous tick species. Eight ticks were PCR-positive, including 6 I. pacificus (one adult, one larva, and 6 nymphs), and 2 adult I. ochotonae and high PCR prevalences of 18% and 9% were detected in woodrats and chipmunks, respectively. Nymphal I. angustus ticks were active year-long with a possible increase in August while larval activity was only observed in December and spring months and adults only during spring and fall. Overall, we show high tick species richness and year-round high levels of

  16. The Importance of Habitat in the Ecology of Decomposition on Rabbit Carcasses in Malaysia: Implications in Forensic Entomology.

    PubMed

    Silahuddin, Siti Aisyah; Latif, Baha; Kurahashi, Hiromu; Walter, David Evans; Heo, Chong Chin

    2015-01-01

    The stages of decomposition and the faunal succession on rabbit carcasses in three different habitats, namely jungle, rural, and highland areas, were studied. Three New Zealand White rabbit (Oryctolagus cuniculus) carcasses weighing ∼2 kg were sampled daily until the decomposition process was completed. Representative specimens of adult flies, larvae, pupa, and mites were collected from the carcasses and processed in the laboratory. There were differences in decomposition rate and faunal succession between the carcasses. The fastest rate of decomposition was recorded in rural area, and the slowest rate of decomposition was recorded in highland area. The carcasses exhibited the same pattern of colonization by adult flies, but the dominant species of larvae and adult flies on each carcass in specific habitats were different. The primary species of flies recorded in jungle were Chrysomya megacephala F., Chrysomya rufifacies (Macquart), Chrysomya chani Kurahashi, Chrysomya villenuevi Patton, Chrysomya nigripes Aubertin, Chrysomya pinguis (Walker), Hemipyrellia ligurriens (Wiedemann), Hemipyrellia tagaliana (Bigot), Hypopyiopsis fumipennis (Walker), Hypopygiopsis violacea (Macquart), and Hydrotaea spinigera Stein represented by both adults and larvae. Musca domestica L., Atherigona sp., Lioproctia pattoni (Senior-White), Lioproctia saprianovae Pape & Bänziger, and Seniorwhitea princeps (Wiedemann) were represented by adults only. The biodiversity of flies in the rural area were C. megacephala, C. rufifacies, H. ligurriens, Fannia canicularis L., Hydrotaea chalcogaster (Wiedemann), and Hyd. spinigera represented by both adults and larvae, meanwhile M. domestica, Atherigona sp., Boettcherisca peregrina (Robineau-Desvoidy), Parasarcophaga taenionota Wiedemann, Parasarcophaga scopariiformis Senior-White, and S. princeps were represented by adults only. The species of flies collected in the highland area were Lucilia porphyrina (Walker), C. megacephala, C. rufifacies, C

  17. Saker falcon research and conservation efforts in Mongolia, 1997

    USGS Publications Warehouse

    Ellis, D.H.; Tsengeg, Pu; Whitlock, P.L.

    1998-01-01

    This past summer. our small field team followed a 4000 km route through central and eastern Mongolia. Even though there was a population crash underway for picas (Ochotona sp.) and voles (Microtus sp.). we found 38 new saker nests and visited 60 eyries found in previous years. Many of the former eyries were unoccupied. Others were occupied but without young. Productivity was good at eyries with large young. and southeastern Mongolia seemed unaffected by food shortages. The main goal for 1997 was to create new eyries and enlarge. stabilise. or otherwise alter marginal eyries. \\Ve created 65 eyries as follows: 8 on wooden powerlines or telephone supports, 8 on metal power line towers, 3 in trees, 3 on boulders, 11 on cliffs, 17 on abandoned buildings, 9 on metal geological survey towers, and 6 on miscellaneous structures. \\Ve also enlarged or repaired three establishedeyries and did minor repairs on several others. Lesser accomplishments include what may be the first observation of siblicide for the saker falcon (please contact us immediately if you have other records of sakerchicks attacking or killing their nest mates) and the description of a new saker flight display. We also documented an unusual golden eagle eyrie containing the remains of nearly 30 foxes, several predatory birds, and a number of gazelle. In 1998. we plan to return to Mongolia to see how many of our 'fake eyries' attracted falcons. Our work in 1997 was supported by Mr. Howell. another philanthropist (anonymous) and the Institute of Raptor Studies.

  18. Transmission ecosystems of Echinococcus multilocularis in China and Central Asia.

    PubMed

    Giraudoux, Patrick; Raoul, Francis; Afonso, Eve; Ziadinov, Iskender; Yang, Yurong; Li, Li; Li, Tiaoying; Quéré, Jean-Pierre; Feng, Xiaohui; Wang, Qian; Wen, Hao; Ito, Akira; Craig, Philip S

    2013-11-01

    From continental to regional scales, the zoonosis alveolar echinococcosis (AE) (caused by Echinococcus multilocularis) forms discrete patches of endemicity within which transmission hotspots of much larger prevalence may occur. Since the late 80s, a number of hotspots have been identified in continental Asia, mostly in China, wherein the ecology of intermediate host communities has been described. This is the case in south Gansu, at the eastern border of the Tibetan plateau, in south Ningxia, in the western Tian Shan of Xinjiang, and in the Alay valley of south Kyrgyzstan. Here we present a comparative natural history and characteristics of transmission ecosystems or ecoscapes. On this basis, regional types of transmission and their ecological characteristics have been proposed in a general framework. Combining climatic, land cover and intermediate host species distribution data, we identified and mapped 4 spatially distinct types of transmission ecosystems typified by the presence of one of the following small mammal 'flagship' species: Ellobius tancrei, Ochotona curzoniae, Lasiopodomys brandtii or Eospalax fontanierii. Each transmission ecosystem had its own characteristics which can serve as a reference for further in-depth research in the transmission ecology of E. multilocularis. This approach may be used at fine spatial scales to characterize other poorly known transmission systems of the large Eurasian endemic zone, and help in consideration of surveillance systems and interventions.

  19. Genetic characterization of the chemokine receptor CXCR4 gene in lagomorphs: comparison between the families Ochotonidae and Leporidae.

    PubMed

    Abrantes, J; Esteves, P J; Carmo, C R; Müller, A; Thompson, G; van der Loo, W

    2008-04-01

    Chemokines receptors are transmembrane proteins that bind chemokines. Chemokines and their receptors are known to play a crucial role in the immune system and in pathogen entry. There is evidence that myxoma virus, the causative agent of myxomatosis, can use the chemokine receptor CXCR4 to infect cells. This virus causes a benign disease in its natural host, Sylvilagus, but in the European rabbit (Oryctolagus cuniculus) it causes a highly fatal and infectious disease known as myxomatosis. We have characterized the chemokine receptor CXCR4 gene in five genera of the order Lagomorpha, Ochotona (Ochotonidae), and Oryctolagus, Lepus, Bunolagus and Sylvilagus (Leporidae). In lagomorphs, the CXCR4 is highly conserved, with most of the protein diversity found at surface regions. Five amino acid replacements were observed, two in the intracellular loops, one in the transmembrane domain and two in the extracellular loops. Oryctolagus features unique amino acid changes at the intracellular domains, putting this genus apart of all other lagomorphs. Furthermore, in the 37 European rabbits analysed, which included healthy rabbits and rabbits with clinical symptoms of myxomatosis, 14 nucleotide substitutions were obtained but no amino acid differences were observed.

  20. [Study on the natural foci of Marmota himalayana plague in Sichuan province].

    PubMed

    Wang, Li-Mao; Luo, Zhi-Danba; Yue, Qi; Duan, Yong-Jun; Zhu, Xiao-Ping; Mao, Su-Ling; Liu, Lun-Guang; Wang, Hong; Liu, Yi; Xie, Fei; Chen, De-Gang; Chen, Kai-Hua; Deng, Bing; Kang, Jun-Xing

    2009-06-01

    To explore the existence of natural foci on Marmota himalayana plague in Sichuan province and to provide basis for prevention and control of the disease. Both epidemiological investigation and laboratory tests were used to provide the host animal and fleas of the vectors with Yersinia pestis carriers. 30 species of animals were found to belong to 10 orders. Ochotona curzoniae and M. himalayana were the most common ones while 7 species of the fleas belonged to 7 genera and 3 families. M. himalayana was the main reservoirs while Callopsylla dolabris and Oropsylla silantiewi served as vectors. The 13 Y. pestis were identified from 43 Marmota samples. 8 samples were identified under IHA, with the highest titer of herding-dogs serum as 1:10,240. 19 samples were F1 antigen positive using RIHA and the highest titer of M. himalayana serum was 1:409,600. The major foci was 4545 km2, distributed at Dege county in Sichuan province. We have confirmed the existence of natural foci on M. himalayana plague in Sichuan province.

  1. Torque patterns of the limbs of small therian mammals during locomotion on flat ground.

    PubMed

    Witte, Hartmut; Biltzinger, Jutta; Hackert, Rémi; Schilling, Nadja; Schmidt, Manuela; Reich, Christian; Fischer, Martin S

    2002-05-01

    In three species of small therian mammals (Scandentia: Tupaia glis, Rodentia: Galea musteloides and Lagomorpha: Ochotona rufescens) the net joint forces and torques acting during stance phase in the four kinematically relevant joints of the forelimbs (scapular pivot, shoulder joint, elbow joint, wrist joint) and the hindlimbs (hip joint, knee joint, ankle joint, intratarsal joint) were determined by inverse dynamic analysis. Kinematics were measured by cineradiography (150 frames s(-1)). Synchronously ground reaction forces were acquired by forceplates. Morphometry of the extremities was performed by a scanning method using structured illumination. The vector sum of ground reaction forces and weight accounts for most of the joint force vector. Inertial effects can be neglected since errors of net joint forces amount at most to 10 %. The general time course of joint torques is comparable for all species in all joints of the forelimb and in the ankle joint. Torques in the intratarsal joints differ between tailed and tail-less species. The torque patterns in the knee and hip joint are unique to each species. For the first time torque patterns are described completely for the forelimb including the scapula as the dominant propulsive segment. The results are compared with the few torque data available for various joints of cats (Felis catus), dogs (Canis lupus f. familiaris), goats (Capra sp.) and horses (Equus przewalskii f. caballus).

  2. Molecular and Phylogenetic Characterization of Non-O157 Shiga Toxin-Producing Escherichia coli Strains in China

    PubMed Central

    Bai, Xiangning; Hu, Bin; Xu, Yanmei; Sun, Hui; Zhao, Ailan; Ba, Pengbin; Fu, Shanshan; Fan, Ruyue; Jin, Yujuan; Wang, Hong; Guo, Qiusheng; Xu, Xuebin; Lu, Shan; Xiong, Yanwen

    2016-01-01

    Shiga toxin-producing Escherichia coli (STEC) causes diarrhea and hemorrhagic colitis with life-threatening complications, such as hemolytic uremic syndrome. The aim of this study was to assess the molecular epidemiologic features of non-O157 STEC strains from different resources in China and illustrate the role of animal reservoirs or animal-derived foodstuffs in human STEC infections. A collection of 301 non-O157 STEC isolates from domestic and wild animals (i.e., cattle, goat, pig, yak, pika, and antelope), raw meats (i.e., beef, pork, mutton, chicken, and duck), diarrheal patients, and healthy carriers in different regions of China were selected in this study. Of the 301 analyzed STEC isolates, 67 serogroups, and 118 serotypes were identified; this included some predominant serogroups associated with human disease, such as O26, O45, O103, O111, and O121. Eighteen different combinations of stx subtypes were found. Eleven isolates carried the intimin gene eae, 93 isolates contained ehxA, and 73 isolates carried astA. The prevalence of other putative adhesion genes saa, paa, efa1, and toxB was 28.90% (87), 6.98% (21), 2.31% (7), and 1% (3), respectively. The phylogenetic distribution of isolates was analyzed by multilocus sequence typing (MLST). Ninety-four sequence types were assigned across the 301 isolates. A subset of isolates recovered from yak and pika residing in the similar wild environments, Qinghai-Tibetan plateau, showed similar genetic profiles and more tendencies to cluster together. Isolates from goat and mutton exhibited close genetic relatedness with those from human-derived isolates, providing evidence that transmission may have occurred locally within intraspecies or interspecies, and importantly, from animal reservoirs, or raw meats to humans. Comparing isolates in this study with highly virulent strains by MLST, along with serotyping and virulence profiles, it is conceivable that some of isolates from goat, yak, or raw meats may have potential

  3. Role of tectonic and volcanic activity in hydrothermal systems at the southern Mariana Trough: detailed bathymetric characteristics of the hydrothermal sites

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Okino, K.; Asada, M.; Nogi, Y.; Mochizuki, N.; Nakamura, K.

    2012-12-01

    We present the detailed bathymetric characterization of field-scale geological features associated with hydrothermal systems in the southern Mariana Trough near 12°57'N, 143°37'E, using near-bottom swath mapping data collected by the autonomous underwater vehicle (AUV) Urashima during cruise YK09-08 and dive observation data acquired by the submersible Shinkai6500 during cruise YK10-11. In the study area, two of the hydrothermal sites are located on the active backarc spreading axis (the Snail and Yamanaka sites), one is located at the eastern foot of the axial high (the Archean site), and two are located on an off-axis knoll about 5 km from the spreading axis (the Pika and Urashima sites). We examined 1) the nature of' tectonic and volcanic controls on the hydrothermal systems, and 2) the relationship between geomorphological characteristics and hydrothermal activity based on the survey results (Yoshikawa et al., 2012). The two on-axis hydrothermal sites are possibly locally developed on a 4th order spreading segment, in association with diking events (on the basis of comparisons with previously studied cases on the East Pacific Rise). The three off-axis sites (the Archean, Urashima, and Pika sites) appear to represent locations of sustained hydrothermal activity that has created relatively large-scale hydrothermal features compared with those in the on-axis area. The formation of off-axis hydrothermal sites is likely to be closely related to an off-axis magma upwelling system, as evidenced by the absence of fault systems and the undeformed morphology of the mound and knoll. The three off-axis hydrothermal sites are composed mainly of breccia assemblages that probably originated from hydrothermal activity with black smoker venting. These areas are characterized by numerous ridge lines (height, mainly 1-6 m), conical mounds (height: < 100 m, diameter: < 300 m), and bumpy seabed. Most of the ridge lines have formed as a result of collapse of the seafloor. The

  4. U-Th and ESR dating of drilled cores from a giant hydrothermal mounds in South Mariana

    NASA Astrophysics Data System (ADS)

    Takamasa, A.; Nakai, S.; Sato, F.; Toyoda, S.; Ishibashi, J.

    2012-12-01

    The time scale for hydrothermal activity is an important factor controlling the size of hydrothermal ore deposits and the evolution of chemosynthesis-based communities in a submarine hydrothermal system. We determined the age of hydrothermal deposits samples, both collected samples by submersible and drilled core samples from South Mariana Trough. Samples were collected from four hydrothermal sites, Snail (near the spreading axis), Archean ( 1.5km from the axis), Pika ( 4.9km from the axis) and Urashima ( 4.9km from the axis). 230Th-234U radioactive disequilibrium dating was applied to hydrothermal sufide minerals consisting of pyrite and sphalerite while electron spin resonance (ESR) dating was applied to barite. For 230Th-234U radioactive disequilibrium dating, we carried out magnetic separation for bulk samples, then we digested samples with nitric acid. U and Th were purified by two-step column separations, and isotopic compositions of spiked and unspiked U and Th were measured by a MC-ICP-MS. Analytical methods for ESR age determination were described in a companion abstract by Toyoda et al. We found that the magnetic fractions had significantly higher U/Th ratios, which enabled 230Th-234U age determinations as precise as ±2% (2σ). This probably reflects that pyrite enriched in magnetic fractions has high U/Th ration. In a sulfide crust sample collected from Archean site, the 230Th-234U ages of the sulfide minerals (0.3-2.2 ka) were compared with ESR ages of barites separated from 12 subsamples of the same sulfide crust. ESR ages (0.27 - 1.7 ka) show a spatial pattern broadly resembling that observed in 230Th-234U dating method. While there are some significant offsets, these results illustrate the potential of the two methods for use in provide information on evolution history of a hydrothermal system. Samples from Pika, Archean and Snail sites yield from 0.5 to ~9 ka, from 0.1 to 3 ka and < ~90 a, respectively. The oldest ages from each site are correlated

  5. Investigations and Mimicry of the Optical Properties of Butterfly Wings

    NASA Astrophysics Data System (ADS)

    Summers, Christopher J.; Gaillot, Davy P.; Crne, Matija; Blair, John; Park, Jung O.; Srinivasarao, Mohan; Deparis, Olivier; Welch, Victoria; Vigneron, Jean-Pol

    Structural color in Nature has been observed in plants, insects and birds, and has led to a strong interest in these phenomena and a desire to understand the mechanisms responsible. Of particular interest are the optical properties of butterflies. In this paper, we review three investigations inspired by the unique optical properties exhibited in a variety of butterfly wings. In the first investigation, conformal atomic layer depositions (ALDs) were used to exploit biologically defined 2D photonic crystal (PC) templates of Papilio blumei with the purpose of increasing the understanding of the optical effects of naturally formed dielectric architectures, and of exploring any novel optical effects. In the second study, it was demonstrated that faithful mimicry of Papilio palinurus can be achieved by physical fabrication methods through using breath figures to provide templates and ALD routines to enable optical properties. Finally, knowledge of the optical structure properties of the Princeps nireus butterfly has resulted in bioinspired designs to enhanced scintillator designs for radiation detection.

  6. Light-induced protein degradation in human-derived cells.

    PubMed

    Sun, Wansheng; Zhang, Wenyao; Zhang, Chao; Mao, Miaowei; Zhao, Yuzheng; Chen, Xianjun; Yang, Yi

    2017-05-27

    Controlling protein degradation can be a valuable tool for posttranslational regulation of protein abundance to study complex biological systems. In the present study, we designed a light-switchable degron consisting of a light oxygen voltage (LOV) domain of Avena sativa phototropin 1 (AsLOV2) and a C-terminal degron. Our results showed that the light-switchable degron could be used for rapid and specific induction of protein degradation in HEK293 cells by light in a proteasome-dependent manner. Further studies showed that the light-switchable degron could also be utilized to mediate the degradation of secreted Gaussia princeps luciferase (GLuc), demonstrating the adaptability of the light-switchable degron in different types of protein. We suggest that the light-switchable degron offers a robust tool to control protein levels and may serves as a new and significant method for gene- and cell-based therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Reversible low-light induced photoswitching of crowned spiropyran-DO3A complexed with gadolinium(III) ions.

    PubMed

    Kruttwig, Klaus; Yankelevich, Diego R; Brueggemann, Chantal; Tu, Chuqiao; L'etoile, Noelle; Knoesen, André; Louie, Angelique Y

    2012-05-31

    Photoswitchable spiropyran has been conjugated to the crowned ring system DO3A, which improves its solubility in dipolar and polar media and stabilizes the merocyanine isomer. Adding the lanthanide ion gadolinium(III) to the macrocyclic ring system leads to a photoresponsive magnetic resonance imaging contrast agent that displays an increased spin-lattice relaxation time (T₁) upon visible light stimulation. In this work, the photoresponse of this photochromic molecule to weak light illumination using blue and green light emitting diodes was investigated, simulating the emission spectra from bioluminescent enzymes. Photon emission rate of the light emitting diodes was changed, from 1.75 × 10¹⁶ photons·s⁻¹ to 2.37 × 10¹² photons·s⁻¹. We observed a consistent visible light-induced isomerization of the merocyanine to the spiropyran form with photon fluxes as low as 2.37 × 10¹² photons·s⁻¹ resulting in a relaxivity change of the compound. This demonstrates the potential for use of the described imaging probes in low light level applications such as sensing bioluminescence enzyme activity. The isomerization behavior of gadolinium(III)-ion complexed and non-complexed spiropyran-DO3A was analyzed in water and ethanol solution in response to low light illumination and compared to the emitted photon emission rate from over-expressed Gaussia princeps luciferase.

  8. Alternative luciferase for monitoring bacterial cells under adverse conditions.

    PubMed

    Wiles, Siouxsie; Ferguson, Kathryn; Stefanidou, Martha; Young, Douglas B; Robertson, Brian D

    2005-07-01

    The availability of cloned luciferase genes from fireflies (luc) and from bacteria (luxAB) has led to the widespread use of bioluminescence as a reporter to measure cell viability and gene expression. The most commonly occurring bioluminescence system in nature is the deep-sea imidazolopyrazine bioluminescence system. Coelenterazine is an imidazolopyrazine derivative which, when oxidized by an appropriate luciferase enzyme, produces carbon dioxide, coelenteramide, and light. The luciferase from the marine copepod Gaussia princeps (Gluc) has recently been cloned. We expressed the Gluc gene in Mycobacterium smegmatis using a shuttle vector and compared its performance with that of an existing luxAB reporter. In contrast to luxAB, the Gluc luciferase retained its luminescence output in the stationary phase of growth and exhibited enhanced stability during exposure to low pH, hydrogen peroxide, and high temperature. The work presented here demonstrated the utility of the copepod luciferase bioluminescent reporter as an alternative to bacterial luciferase, particularly for monitoring responses to environmental stress stimuli.

  9. In vitro anti-herpes simplex viruses and anti-adenoviruses activity of twelve traditionally used medicinal plants in Taiwan.

    PubMed

    Chiang, Lien-Chai; Cheng, Hua-Yew; Liu, Mei-Chi; Chiang, Wen; Lin, Chun-Ching

    2003-11-01

    As an effort to search for new antiviral agents from traditional medicine, the hot water (HW) extract of twelve traditionally used medicinal plants in Taiwan was evaluated for their in vitro anti-herpes simplex viruses (HSV; including HSV-1 and HSV-2) and anti-adenoviruses (ADV; including ADV-3, ADV-8 and ADV-11) activities with a XTT-based colorimetric assay. Results showed that the tested HW extracts exhibited anti-HSV and anti-ADV activities at different magnitudes of potency. Among the twelve medicinal plants, Boussingaultia gracilis var. pseudobaselloides (Basellaceae) and Serissa japonica (Rubiaceae) possessed broad spectrum of antiviral activity. Ardisia squamulosa (Myrsinaceae) and Artemisai princeps var. orientalis (Compositae) were more effective in inhibiting ADV-8 replication than the other four viruses. Cell cytotoxic assay demonstrated that all tested HW extracts had CC50 values higher than their EC50 values. It was concluded that the twelve traditionally used medicinal plants in Taiwan possessed antiviral activity, and some of them merit further investigation.

  10. Convergent patterns in the evolution of mealybug symbioses involving different intrabacterial symbionts.

    PubMed

    Szabó, Gitta; Schulz, Frederik; Toenshoff, Elena R; Volland, Jean-Marie; Finkel, Omri M; Belkin, Shimshon; Horn, Matthias

    2017-03-01

    Mealybugs (Insecta: Hemiptera: Pseudococcidae) maintain obligatory relationships with bacterial symbionts, which provide essential nutrients to their insect hosts. Most pseudococcinae mealybugs harbor a unique symbiosis setup with enlarged betaproteobacterial symbionts ('Candidatus Tremblaya princeps'), which themselves contain gammaproteobacterial symbionts. Here we investigated the symbiosis of the manna mealybug, Trabutina mannipara, using a metagenomic approach. Phylogenetic analyses revealed that the intrabacterial symbiont of T. mannipara represents a novel lineage within the Gammaproteobacteria, for which we propose the tentative name 'Candidatus Trabutinella endobia'. Combining our results with previous data available for the nested symbiosis of the citrus mealybug Planococcus citri, we show that synthesis of essential amino acids and vitamins and translation-related functions partition between the symbiotic partners in a highly similar manner in the two systems, despite the distinct evolutionary origin of the intrabacterial symbionts. Bacterial genes found in both mealybug genomes and complementing missing functions in both symbioses were likely integrated in ancestral mealybugs before T. mannipara and P. citri diversified. The high level of correspondence between the two mealybug systems and their highly intertwined metabolic pathways are unprecedented. Our work contributes to a better understanding of the only known intracellular symbiosis between two bacteria and suggests that the evolution of this unique symbiosis included the replacement of intrabacterial symbionts in ancestral mealybugs.

  11. Repeated replacement of an intrabacterial symbiont in the tripartite nested mealybug symbiosis

    PubMed Central

    Husnik, Filip; McCutcheon, John P.

    2016-01-01

    Stable endosymbiosis of a bacterium into a host cell promotes cellular and genomic complexity. The mealybug Planococcus citri has two bacterial endosymbionts with an unusual nested arrangement: the γ-proteobacterium Moranella endobia lives in the cytoplasm of the β-proteobacterium Tremblaya princeps. These two bacteria, along with genes horizontally transferred from other bacteria to the P. citri genome, encode gene sets that form an interdependent metabolic patchwork. Here, we test the stability of this three-way symbiosis by sequencing host and symbiont genomes for five diverse mealybug species and find marked fluidity over evolutionary time. Although Tremblaya is the result of a single infection in the ancestor of mealybugs, the γ-proteobacterial symbionts result from multiple replacements of inferred different ages from related but distinct bacterial lineages. Our data show that symbiont replacement can happen even in the most intricate symbiotic arrangements and that preexisting horizontally transferred genes can remain stable on genomes in the face of extensive symbiont turnover. PMID:27573819

  12. The Ordovician acritarch genera Tranvikium and Ampullula: their relationship and taxonomy.

    PubMed

    Uutela; Sarjeant

    2000-10-01

    A restudy of the Ordovician (Arenig-Llanvirn) acritarch taxa Tranvikium polygonale Tynni, 1982, and Ampullula suetica Righi, 1991, indicates that they represent extremes in a single morphological plexus. At one extreme are forms with a polar 'excystment' aperture (closed by an operculum or two opercular pieces) and a smaller opening (plugged or open) at the opposite pole; at the other are forms lacking a polar aperture but having, at the opposite pole, a tube open distally and plugged or open basally. New morphological terms for these structures are proposed. The genera and species are treated as synonyms and an emended diagnosis is given for Tranvikium polygonale, incorporating this whole morphological plexus. The possible purposes of the structures exhibited and the likely affinity of T. polygonale to various groups of algae are discussed. The emendation of Ampullula by Brocke (1997) is rejected and the genus Stelomorpha Yin, 1994 retained, with an emended diagnosis. The new combination Stelomorpha princeps (Brocke, 1997) Uutela and Sarjeant is proposed.

  13. DNA-based characterisation and classification of forensically important flesh flies (Diptera: Sarcophagidae) in Malaysia.

    PubMed

    Tan, Siew Hwa; Rizman-Idid, Mohammed; Mohd-Aris, Edah; Kurahashi, Hiromu; Mohamed, Zulqarnain

    2010-06-15

    Insect larvae and adult insects found on human corpses provide important clues for the estimation of the postmortem interval (PMI). Among all necrophagous insects, flesh flies (Diptera: Sarcophagidae) are considered as carrion flies of forensic importance. DNA variations of 17 Malaysian, two Indonesian and one Japanese flesh fly species are analysed using the mitochondrial COI and COII. These two DNA regions were useful for identifying most species experimented. However, characterisation of the species was not sufficiently made in the case of Sarcophaga javanica. Seventeen Malaysian species of forensic importance were successfully clustered into distinct clades and grouped into the six species groups: peregrina, albiceps, dux, pattoni, princeps and ruficornis. These groups correspond with generic or subgeneric taxa of the subfamily Sarcophaginae: Boettcherisca, Parasarcophaga, Liosarcophaga, Sarcorohdendorfia-Lioproctia, Harpagophalla-Seniorwhitea and Liopygia. The genetic variations found in COI and COII can be applied not only to identify the species of forensic importance, but also to understand the taxonomic positions, generic or subgeneric status, of the sarcophagine species.

  14. Permanent Genetic Resources added to Molecular Ecology Resources database 1 January 2009-30 April 2009.

    PubMed

    Abercrombie, L G; Anderson, C M; Baldwin, B G; Bang, I C; Beldade, R; Bernardi, G; Boubou, A; Branca, A; Bretagnolle, F; Bruford, M W; Buonamici, A; Burnett, R K; Canal, D; Cárdenas, H; Caullet, C; Chen, S Y; Chun, Y J; Cossu, C; Crane, C F; Cros-Arteil, S; Cudney-Bueno, R; Danti, R; Dávila, J A; Della Rocca, G; Dobata, S; Dunkle, L D; Dupas, S; Faure, N; Ferrero, M E; Fumanal, B; Gigot, G; González, I; Goodwin, S B; Groth, D; Hardesty, B D; Hasegawa, E; Hoffman, E A; Hou, M L; Jamsari, A F J; Ji, H J; Johnson, D H; Joseph, L; Justy, F; Kang, E J; Kaufmann, B; Kim, K S; Kim, W J; Koehler, A V; Laitung, B; Latch, P; Liu, Y D; Manjerovic, M B; Martel, E; Metcalfe, S S; Miller, J N; Midgley, J J; Migeon, A; Moore, A J; Moore, W L; Morris, V R F; Navajas, M; Navia, D; Neel, M C; De Nova, P J G; Olivieri, I; Omura, T; Othman, A S; Oudot-Canaff, J; Panthee, D R; Parkinson, C L; Patimah, I; Pérez-Galindo, C A; Pettengill, J B; Pfautsch, S; Piola, F; Potti, J; Poulin, R; Raimondi, P T; Rinehart, T A; Ruzainah, A; Sarver, S K; Scheffler, B E; Schneider, A R R; Silvain, J F; Siti Azizah, M N; Springer, Y P; Stewart, C N; Sun, W; Tiedemann, R; Tsuji, K; Trigiano, R N; Vendramin, G G; Wadl, P A; Wang, L; Wang, X; Watanabe, K; Waterman, J M; Weisser, W W; Westcott, D A; Wiesner, K R; Xu, X F; Yaegashi, S; Yuan, J S

    2009-09-01

    This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis.

  15. Variant Superficial Branch of Radial Artery along with Supplementary Tendons on the Dorsum of the Hand and Their Surgical Implications

    PubMed Central

    Shetty, Surekha D.

    2016-01-01

    Variations of radial artery, in both its course and branching pattern in the anatomical snuffbox, are clinically significant for the plastic surgeons, cardiologists, and radiologists. Reports on its abnormal high origin and subsequent superficial course have been well documented. Herein, we report an unusual superficial branch of the radial artery given off before its entry into the palm by passing between the two heads of first dorsal interosseous. It eventually divided into princeps pollicis and radialis indicis arteries at the first web space of palm as a unique vascular variation. Apart from this, in the present case, the tendon of extensor digiti minimi and of extensor indicis divided into two parts. The split tendons of extensor digiti minimi were inserted to the dorsal digital expansion of the digitus minimus. However, lateral tendon of split extensor indicis was inserted along with the tendon of extensor digitorum to the index finger and the medial one was inserted along with the tendon of extensor digitorum to the middle finger. Unusual superficial branch of radial artery on the dorsum of the hand is vulnerable for an iatrogenic injury during surgical approaches in the region. Supplementary extensor tendons on the hand are one of the potential causes for the tenosynovitis. PMID:27818829

  16. Balzac's Louis Lambert : schizophrenia before Kraepelin and Bleuler.

    PubMed

    Dieguez, Sebastian

    2013-01-01

    Honoré de Balzac (1799-1850) is well known for his penetrating observations and descriptions of the burgeoning social life and emerging modernity of 19th century France. This chapter focuses on the novel Louis Lambert, first published in 1832. It is argued that its main character provides the first complete and convincing description of schizophrenia - 69 years before Kraepelin fully developed the concept of dementia praecox and 76 years before Bleuler coined the word 'schizophrenia'. We consider the history of the concept of schizophrenia and the intriguing possibility that it is a recent disease. Indeed, if schizophrenia had always existed, it would seem odd that Balzac's novel should be the very first convincing and complete literary account of the disease. This claim is examined by a thorough description of Louis Lambert's symptoms as they appear in the text, and compared to other claims of priority (namely, Shakespeare's King Lear and Gogol's Diary of a Madman). The chapter also provides some background on Balzac's relationship with mysticism, mental illness, and the world of psychiatry. We conclude with remarks regarding influences of Louis Lambert, the case for the priority of the novel as the princeps case of schizophrenia, and its relevance to the recency hypothesis of schizophrenia.

  17. Circularly permutated bioluminescent probes for illuminating ligand-activated protein dynamics.

    PubMed

    Kim, Sung Bae; Sato, Moritoshi; Tao, Hiroaki

    2008-12-01

    Engineered bioluminescent enzymes provide a creative approach for illuminating the intracellular molecular events. We demonstrate a new strategy for molecular imaging of bioactive small molecules using circularly permutated luciferases (cpLuc), derived from Gaussia princeps (GLuc), Photinus pyralis (FLuc), and Pyrearinus termitilluminans (CBLuc): (i) the luciferases were first dissected into two fragments, (ii) the original N- and C-termini were linked with a GS linker and the new termini were created in an appropriate site, and (iii) the new ends were correspondingly linked with proteins of interest, e.g., a ligand-binding domain (LBD) and an LBD-recognition protein. When the ends of the cpCBLuc were linked with LBD of estrogen receptor (ER) and Src homology 2 domain of Src (SH2 of Src), the estrogen can trigger an intramolecular ER LBD-Src SH2 binding. This assembly subsequently provokes an approximation of the adjacent fragments of cpCBLuc recovering the enzyme activity. These probes were surprisingly stable in the mammalian cells and largely exhibited a decreased background luminescence (e.g., 1000 times in case of cpGLuc) and improved signal-to-noise ratios, compared with the non-CP indicators. This study offers a new strategy for luciferase-aided probing systems. Our study is the first to fabricate circular permutation (CP) in luciferases for tracing the molecular dynamics of proteins.

  18. Eupatilin protects against tumor necrosis factor-α-mediated inflammation inhuman umbilical vein endothelial cells.

    PubMed

    Yu, Kai; Li, Xi-Ming; Xu, Xiao-Lei; Zhang, Ru-Yan; Cong, Hong-Liang

    2015-01-01

    Inflammatory responses in the blood vessel play a pivotal role in the pathogenesis of atherosclerosis. Eupatilin, a flavone derived from Artemisia princepsPampanini, has various pharmacological activities, including antioxidant, anti-tumor, and anti-inflammatory capacities. However, there has been no research examining the function of eupatilin on vascular inflammation. Therefore, the aim of this study was to investigate the effects of eupatilin on tumor necrosis factor (TNF)-α-induced human umbilical vein endothelial cells (HUVECs) activation and the underlying molecular mechanisms. Our findings showed that eupatilin reduced U937 cells adhesion to TNF-α-stimulated HUVECs and attenuated TNF-α-induced the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in HUVECs, as well as the production of intracellular reactive oxygen species (ROS). Moreover, eupatilininhibits TNF-α-induced phosphorylation of NF-kB p65 and MAPKs in HUVECs. Taken together, the results of the present study suggest that eupatilin inhibited inflammatory reaction through suppressing the ROS/MAPK-NF-ĸB pathway in HUVECs. Thus, eupatilin is proposed as an effective new anti-inflammatory agent to suppress vascular inflammation, and further prevent atherosclerosis.

  19. The Anti-Inflammatory Effects and Mechanisms of Eupafolin in Lipopolysaccharide-Induced Inflammatory Responses in RAW264.7 Macrophages

    PubMed Central

    Chen, Chin-Chaun; Lin, Ming-Wei; Liang, Chan-Jung; Wang, Shu-Huei

    2016-01-01

    Eupafolin is a flavone isolated from Artemisia princeps Pampanini (family Asteraceae). The aim of this study was to examine the anti-inflammatory effects of eupafolin in lipopolysaccharide (LPS)-treated RAW264.7 macrophages and LPS-induced mouse skin and lung inflammation models and to identify the mechanism underlying these effects. Eupafolin decreased the LPS-induced release of inflammatory mediators (iNOS, COX-2 and NO) and proinflammatory cytokines (IL-6 and TNF-α) from the RAW264.7 macrophages. Eupafolin inhibited the LPS-induced phosphorylation of p38 MAPK, ERK1/2, JNK, AKT and p65 and the nuclear translocation of p65 and c-fos. These effects were mainly mediated by the inhibition of JNK. In the mouse paw and lung models, eupafolin effectively suppressed the LPS-induced edema formation and down-regulated iNOS and COX-2 expression. These results demonstrated that eupafolin exhibits anti-inflammatory properties and suggested that eupafolin can be developed as an anti-inflammatory agent. PMID:27414646

  20. Molecular and Histological Characterization of Primary (Betaproteobacteria) and Secondary (Gammaproteobacteria) Endosymbionts of Three Mealybug Species

    PubMed Central

    Sutherland, Paul; Forgie, Shaun A.; Kaji, Ryohei; Christeller, John T.

    2012-01-01

    Microscopic localization of endosymbiotic bacteria in three species of mealybug (Pseudococcus longispinus, the long-tailed mealybug; Pseudococcus calceolariae, the citrophilus mealybug; and Pseudococcus viburni, the obscure mealybug) showed these organisms were confined to bacteriocyte cells within a bacteriome centrally located within the hemocoel. Two species of bacteria were present, with the secondary endosymbiont, in all cases, living within the primary endosymbiont. DNA from the dissected bacteriomes of all three species of mealybug was extracted for analysis. Sequence data from selected 16S rRNA genes confirmed identification of the primary endosymbiont as “Candidatus Tremblaya princeps,” a betaproteobacterium, and the secondary endosymbionts as gammaproteobacteria closely related to Sodalis glossinidius. A single 16S rRNA sequence of the primary endosymbiont was found in all individuals of each mealybug species. In contrast, the presence of multiple divergent strains of secondary endosymbionts in each individual mealybug suggests different evolutionary and transmission histories of the two endosymbionts. Mealybugs are known vectors of the plant pathogen Grapevine leafroll-associated virus 3. To examine the possible role of either endosymbiont in virus transmission, an extension of the model for interaction of proteins with bacterial chaperonins, i.e., GroEL protein homologs, based on mobile-loop amino acid sequences of their GroES homologs, was developed and used for analyses of viral coat protein interactions. The data from this model are consistent with a role for the primary endosymbiont in mealybug transmission of Grapevine leafroll-associated virus 3. PMID:22156418

  1. Electrical nature of the taxis signal in cyanobacteria.

    PubMed

    Murvanidze, G V; Glagolev, A N

    1982-04-01

    Electrical events after a light-dark stimulus were studied in the multicellular organism Phormidium uncinatum. Normally, such a stimulus causes the gliding trichome to reverse direction. By directing a large light spot on the end of a batch of trichomes and then switching it off, we achieved synchronization of the trichomes, since the "head" is much more sensitive than the "tail." The abrupt disappearance of a uniform light produced a depolarization wave which initiated at the head, as registered by externally applied electrodes. The second stimulus produced a depolarization of the opposite direction, reflecting the reorientation of the trichomes. No electrical response was observed at Ca2+ concentrations less than or equal to 10(-8) M. Factors causing oscillatory reversals, i.e., a combination of Ca2+ and A23187, or a viscous environment also abolished the electrical signal. Changes in an externally applied electrical field (4 V/cm2) had little effect on the motile behavior of P. uncinatum or Oscillatoria princeps. However, in the presence of 5 microM Ca2+-1 microM A23187, all the trichomes reversed synchronously to the anode after a change in polarity of an externally applied electrical field. We suggest that an increased Ca2+ concentration together with a change in delta psi (or delta mu H+) represents the taxis signal in cyanobacteria.

  2. Complete mitochondrial genome of the stonefly Cryptoperla stilifera Sivec (Plecoptera: Peltoperlidae) and the phylogeny of Polyneopteran insects.

    PubMed

    Wu, Hai-Yan; Ji, Xiao-Yu; Yu, Wei-Wei; Du, Yu-Zhou

    2014-03-10

    We present the complete mitogenome of a stonefly, Cryptoperla stilifera Sivec (Plecoptera; Peltoperlidae). The mitogenome was a circular molecule consisting of 15,633 nucleotides, 37 genes and a A+T-rich region. C. stilifera mitogenome was similar to Pteronarcys princeps mitogenome (Plecoptera; Pteronarcyidae). All transfer RNA genes (tRNAs) had typical cloverleaf secondary structures except for trnSer (AGN), where the stem-loop structure of the dihydrouridine (DHU) arm was missing. The A+T-rich region of C. stilifera had two stem-loops and each had two interlink. Three conserved sequence blocks (CSBs) were present in the A+T-rich regions of C. stilifera, Peltoperla tarteri and Peltoperla arcuata. Moreover, many polynucleotide stretches (Poly N, N=A, T and C) in the A+T-rich region of C. stilifera Phylogenetic relationships of Polyneopteran species were constructed based on the nucleotide sequences of 13 protein coding genes (PCGs). Both maximum likelihood (ML) and Bayesian inference (BI) analyses supported Grylloblattodea as the sister group to Plecoptera+Dermaptera and Embiidina and Phasmatodea as sister groups.

  3. Molecular evolution in bacterial endosymbionts of fungi.

    PubMed

    Castillo, Dean M; Pawlowska, Teresa E

    2010-03-01

    The prediction that progressive coupling of host and symbiont metabolic and reproductive interests leads to reduced mixing of symbiont lineages has been verified extensively in maternally transmitted bacterial endosymbionts of insects. To test whether this prediction is also applicable to associations of bacteria with fungi, we explored patterns of molecular evolution in two lineages of mutualistic endosymbionts of fungi: the Burkholderia endosymbionts of Rhizopus microsporus (Mucormycotina) and Candidatus Glomeribacter gigasporarum endosymbionts of arbuscular mycorrhizal fungi (Glomeromycota). We compared these two lineages with the closely related Candidatus Tremblaya princeps endosymbionts of mealybugs (Hemiptera, Coccoidea, Pseudococcidae) and to free-living Burkholderia species. To make inferences about the life histories of the endosymbionts, we relied on the empirically validated predictions of the nearly neutral theory of molecular evolution that a reduction of the effective population size increases the rate of fixation of slightly deleterious mutations. Our analyses showed that the slightly deleterious mutation accumulation patterns in the Burkholderia endosymbionts of Rhizopus were nearly indistinguishable from those in their free-living relatives. In contrast, Ca. Glomeribacter showed unique patterns of molecular evolution that differentiated them from both the Burkholderia endosymbionts of Rhizopus and from the Ca. Tremblaya endosymbionts of insects. These findings imply that reduced mixing of symbiont lineages is not a universal feature of symbioses between fungi and endocellular bacteria.

  4. An interdependent metabolic patchwork in the nested symbiosis of mealybugs

    PubMed Central

    McCutcheon, John P.; von Dohlen, Carol D.

    2011-01-01

    Summary Highly reduced genomes of 144–416 kilobases have been described from nutrient-provisioning bacterial symbionts of several insect lineages [1–5]. Some host insects have formed stable associations with pairs of bacterial symbionts that live in specialized cells and provide them with essential nutrients; genomic data from these systems have revealed remarkable levels of metabolic complementary between the symbiont pairs [3, 4, 6, 7]. The mealybug, Planococcus citri (Hemiptera: Pseudococcidae), contains dual bacterial symbionts existing with an unprecedented organization: an unnamed Gammaproteobacteria, for which we propose the name Candidatus Moranella endobia, lives inside the Betaproteobacteria Candidatus Tremblaya princeps [8]. Here we describe the complete genomes and metabolic contributions of these unusual nested symbionts. We show that while there is little overlap in retained genes involved in nutrient production between symbionts, several essential amino acid pathways in the mealybug assemblage require a patchwork of interspersed gene products from Tremblaya, Moranella, and possibly P. citri. Furthermore, while Tremblaya has the smallest cellular genome yet described, it contains a genomic inversion present in both orientations in individual insects, starkly contrasting the extreme structural stability typical of highly reduced bacterial genomes [4, 9, 10]. PMID:21835622

  5. Molecular and histological characterization of primary (betaproteobacteria) and secondary (gammaproteobacteria) endosymbionts of three mealybug species.

    PubMed

    Gatehouse, Laurence N; Sutherland, Paul; Forgie, Shaun A; Kaji, Ryohei; Christeller, John T

    2012-02-01

    Microscopic localization of endosymbiotic bacteria in three species of mealybug (Pseudococcus longispinus, the long-tailed mealybug; Pseudococcus calceolariae, the citrophilus mealybug; and Pseudococcus viburni, the obscure mealybug) showed these organisms were confined to bacteriocyte cells within a bacteriome centrally located within the hemocoel. Two species of bacteria were present, with the secondary endosymbiont, in all cases, living within the primary endosymbiont. DNA from the dissected bacteriomes of all three species of mealybug was extracted for analysis. Sequence data from selected 16S rRNA genes confirmed identification of the primary endosymbiont as "Candidatus Tremblaya princeps," a betaproteobacterium, and the secondary endosymbionts as gammaproteobacteria closely related to Sodalis glossinidius. A single 16S rRNA sequence of the primary endosymbiont was found in all individuals of each mealybug species. In contrast, the presence of multiple divergent strains of secondary endosymbionts in each individual mealybug suggests different evolutionary and transmission histories of the two endosymbionts. Mealybugs are known vectors of the plant pathogen Grapevine leafroll-associated virus 3. To examine the possible role of either endosymbiont in virus transmission, an extension of the model for interaction of proteins with bacterial chaperonins, i.e., GroEL protein homologs, based on mobile-loop amino acid sequences of their GroES homologs, was developed and used for analyses of viral coat protein interactions. The data from this model are consistent with a role for the primary endosymbiont in mealybug transmission of Grapevine leafroll-associated virus 3.

  6. Lassa and Ebola virus inhibitors identified using minigenome and recombinant virus reporter systems.

    PubMed

    Welch, Stephen R; Guerrero, Lisa Wiggleton; Chakrabarti, Ayan K; McMullan, Laura K; Flint, Mike; Bluemling, Gregory R; Painter, George R; Nichol, Stuart T; Spiropoulou, Christina F; Albariño, César G

    2016-12-01

    Lassa virus (LASV) and Ebola virus (EBOV) infections are important global health issues resulting in significant morbidity and mortality. While several promising drug and vaccine trials for EBOV are ongoing, options for LASV infection are currently limited to ribavirin treatment. A major factor impeding the development of antiviral compounds to treat these infections is the need to manipulate the virus under BSL-4 containment, limiting research to a few institutes worldwide. Here we describe the development of a novel LASV minigenome assay based on the ambisense LASV S segment genome, with authentic terminal untranslated regions flanking a ZsGreen (ZsG) fluorescent reporter protein and a Gaussia princeps luciferase (gLuc) reporter gene. This assay, along with a similar previously established EBOV minigenome, was optimized for high-throughput screening (HTS) of potential antiviral compounds under BSL-2 containment. In addition, we rescued a recombinant LASV expressing ZsG, which, in conjunction with a recombinant EBOV reporter virus, was used to confirm any potential antiviral hits in vitro. Combining an initial screen to identify potential antiviral compounds at BSL-2 containment before progressing to HTS with infectious virus will reduce the amount of expensive and technically challenging BSL-4 containment research. Using these assays, we identified 6-azauridine as having anti-LASV activity, and demonstrated its anti-EBOV activity in human cells. We further identified 2'-deoxy-2'-fluorocytidine as having potent anti-LASV activity, with an EC50 value 10 times lower than that of ribavirin.

  7. Invasion of toxic marine cyanobacteria in to the tsunami affected coastal villages of southern India.

    PubMed

    Muthukumaravel, S; Padmanabhan, V; Boopathidoss, P S; Sadanandane, C; Srinivasan, R; Gunasekaran, K; Sabesan, S; Balaraman, K

    2010-06-01

    This documentation explores the facts about the invasion of marine cyanobacteria in to the tsunami affected coastal villages of Nagapattinam district of Tamilnadu and Karaikkal district of Pondicherry Union Territory (UT) in southern India. Water samples were collected from eight tsunami-hit coastal villages in different open water sources. The collected samples were processed for detecting marine cyanobacterial growth. Totally 110 water samples were processed, three samples were positive for the toxic cyanobacteria, Lyngbya sp., and nine for nontoxic species such as Epithemia sp.,, Johannesbaptistia pellucida, Oscillatoria princeps, Phormidium fragile, Synechocystis sp. Besides posing a public health risk because of the toxic cyanobacteria, the bloom formation by the cyanobacterial species such as Anabaena, Microcystis, Lyngbya, Plectonema, Phormidium contaminated the water bodies and deteriorated the water quality in the tsunami affected villages. The study revealed that another kind of public health risk from the invasion of toxic cyanobacteria to the costal ecosystem during the tsunami. It is necessary, in this context, that the surveillance mechanism, which is geared up during or after natural disasters, should have a provision to monitor the transportation of toxic elements/organisms from marine system to coastal/inland ecosystems and to control such organisms.

  8. Convergent patterns in the evolution of mealybug symbioses involving different intrabacterial symbionts

    PubMed Central

    Szabó, Gitta; Schulz, Frederik; Toenshoff, Elena R; Volland, Jean-Marie; Finkel, Omri M; Belkin, Shimshon; Horn, Matthias

    2017-01-01

    Mealybugs (Insecta: Hemiptera: Pseudococcidae) maintain obligatory relationships with bacterial symbionts, which provide essential nutrients to their insect hosts. Most pseudococcinae mealybugs harbor a unique symbiosis setup with enlarged betaproteobacterial symbionts (‘Candidatus Tremblaya princeps'), which themselves contain gammaproteobacterial symbionts. Here we investigated the symbiosis of the manna mealybug, Trabutina mannipara, using a metagenomic approach. Phylogenetic analyses revealed that the intrabacterial symbiont of T. mannipara represents a novel lineage within the Gammaproteobacteria, for which we propose the tentative name ‘Candidatus Trabutinella endobia'. Combining our results with previous data available for the nested symbiosis of the citrus mealybug Planococcus citri, we show that synthesis of essential amino acids and vitamins and translation-related functions partition between the symbiotic partners in a highly similar manner in the two systems, despite the distinct evolutionary origin of the intrabacterial symbionts. Bacterial genes found in both mealybug genomes and complementing missing functions in both symbioses were likely integrated in ancestral mealybugs before T. mannipara and P. citri diversified. The high level of correspondence between the two mealybug systems and their highly intertwined metabolic pathways are unprecedented. Our work contributes to a better understanding of the only known intracellular symbiosis between two bacteria and suggests that the evolution of this unique symbiosis included the replacement of intrabacterial symbionts in ancestral mealybugs. PMID:27983719

  9. Eupafolin enhances TRAIL-mediated apoptosis through cathepsin S-induced down-regulation of Mcl-1 expression and AMPK-mediated Bim up-regulation in renal carcinoma Caki cells

    PubMed Central

    Woo, Seon Min; Seo, Bo Ram; Kwon, Taeg Kyu

    2016-01-01

    Eupafolin, a flavone found in Artemisia princeps, has been reported for its anti-tumor activity in several cancer cells. In this study, we examined whether eupafolin could sensitize TRAIL-mediated apoptosis in human renal carcinoma Caki cells. We found that eupafolin alone and TRAIL alone had no effect on apoptosis. However, combined treatment with eupafolin and TRAIL markedly induced apoptosis in human renal carcinoma (Caki) cells, glioma cells (U251MG), and prostate cancer cells (DU145), but not normal cells [mesangial cells (MC) and normal mouse kidney cells (TCMK-1)]. Eupafolin induced down-regulation of Mcl-1 expression at the post-translational levels in cathepsin S-dependent manner, and over-expression of Mcl-1 markedly blocked apoptosis induced by combined treatment with eupafolin and TRAIL. In addition, eupafolin increased Bim expression at the post-translational levels via AMP-activated protein kinase (AMPK)-mediated inhibition of proteasome activity. Knock-down of Bim expression by siRNA inhibited eupafolin plus TRAIL-induced apoptosis. Furthermore, combined treatment with eupafolin and TRAIL reduced tumor growth in xenograft models. Taken together, these results suggest that eupafolin enhanced TRAIL-mediated apoptosis via down-regulation of Mcl-1 and up-regulation of Bim in renal carcinoma Caki cells. PMID:27582546

  10. Stereotactic disconnection of hypothalamic hamartoma to control seizure and behavior disturbance: case report and literature review.

    PubMed

    de Almeida, Antonio Nogueira; Fonoff, Erich Talamoni; Ballester, Gerson; Teixeira, Manoel Jacobsen; Marino, Raul

    2008-07-01

    An 18-year-old boy with refractory epilepsy and aggressiveness associated to a hypothalamic hamartoma was submitted to a stereotactically guided lesion by thermocoagulation. The target was based on magnetic resonance (MR) images merged with computed tomography scan images taken on the day of surgery while patient was on a stereotactic frame. In order to reveal structures not discernible in MR images, the Schaltenbrand digital brain atlas was merged onto the patient's images. Target and trajectory of the depth electrode were chosen based on three-dimensional imaging reconstructions. A surgical plan was devised to disconnect the hypothalamic hamartoma from the hypothalamus, medial forebrain bundle, fasciculus princeps, and dorsal longitudinal fasciculus. Our target was placed at the inferior portion of the posterolateral component of the hamartoma, bordering the normal hypothalamus. The patient evolved with marked lessening of aggressiveness. Seizure frequency was reduced from several seizures per day to less than one tonic-clonic seizure during sleep per month and only two episodes suggestive of partial complex seizures during daytime. These results have remained consistent over a 24-month postoperative follow-up. Functional neuroanatomy of hypothalamic connections involved in seizure propagation and aggressive behavior was reviewed.

  11. [Size structure, selectivity and specific composition of the catch in traps for marine fish in the Gulf of California].

    PubMed

    Nevárez-Martínez, Manuel O; Balmori-Ramírez, Alejandro; Miranda-Mier, Everardo; Santos-Molina, J Pablo; Méndez-Tenorio, Francisco J; Cervantes-Valle, Celio

    2008-09-01

    We analyzed the performance of three traps for marine fish between October 2005 and August 2006 in the Gulf of California, Mexico. The performance was measured as difference in selectivity, fish diversity, size structure and yield. The samples were collected with quadrangular traps 90 cm wide, 120 cm long and 50 cm high. Trap type 1 had a 5 x 5 cm mesh (type 2: 5 x 5 cm including a rear panel of 5 x 10 cm; trap 3: 5 x 10 cm). Most abundant in our traps were: Goldspotted sand bass (Paralabrax auroguttatus), Ocean whitefish (Caulolatilus princeps), Spotted sand bass (P. maculatofaciatus) and Bighead tilefish (C. affinis); there was no bycatch. The number offish per trap per haul decreased when mesh size was increased. We also observed a direct relationship between mesh size and average fish length. By comparing our traps with the authorized fishing gear (hooks-and-line) we found that the size structure is larger in traps. Traps with larger mesh size were more selective. Consequently, we recommend adding traps to hooks-and-line as authorized fishing gear in the small scale fisheries of the Sonora coast, Mexico.

  12. Bioinspired Structures and Devices for Nanophotonics

    NASA Astrophysics Data System (ADS)

    Summers, Christopher J.

    2010-03-01

    The catalog of novel material structures and device concepts being discovered in biological systems continues to grow with astonishing speed. Nature's ``innovations'' include various strategies for structural coloration,footnotetext M. Srinivasarao, Chemical Reviews 99, 1935 (1999) broadband nanostructured low- and high-reflective surfaces, photonic crystal light collection schemes and unique multi-colored polarization based vision systems. Nature achieves these effects using very low-index structures and hierarchal fabrication schemes. In this presentation we review some of these key discoveries and present physical based fabrication strategies that emulate nature. For example, the green wing color of the Papilio palinurus butterfly results from a micro-bowl array formed from multilayers of air and chitin and is a consequence of the mixing of yellow light reflected from the bottom of the bowls and blue light reflected from the sides of the bowls.footnotetext P. Vukusic, J. R. Sambles, C. R. Lawrence, Nature 404, 457 (2000) We have emulated this strategy by using breath figure templated self-assembly to mimic the microbowl structure and then by atomic layer deposition of TiO2/Al2O3 multilayer films obtained the same coloration as the original butterfly structure. Additionally, other bioinspired schemes, such as those derived from the fluorescence properties displayed by the Princeps nireus butterfly which have lead to new concepts for detecting thermal neutrons, are presented.

  13. Parasitism of immature stages of Haemaphysalis sulcata (Acari: Ixodidae) on some reptiles in Turkey.

    PubMed

    Keskin, Adem; Bursali, Ahmet; Kumlutas, Yusuf; Ilgaz, Cetin; Tekin, Saban

    2013-10-01

    Reptiles may contribute to maintaining tick populations by feeding larvae, nymphs, and adults. The life cycles and tick-host associations of many Turkish ticks are still poorly known, and only 3 ixodid tick species have been reported on 7 reptile species in Turkey. In this study, we performed a tick survey on reptiles in the Southeastern Anatolia Region of Turkey. In 2005, 57 reptiles (52 lizards and 5 snakes) comprising 10 species from 5 families were captured and examined for tick infestation. A total of 427 ticks was collected. The majority of ticks found on lizards was the immature stages of Haemaphysalis sulcata, 420 larvae and 4 nymphs. The only adult ticks recorded on the agamid lizard, Laudakia stellio, were Hyalomma aegyptium (1 ♂, 2 ♀). The highest tick infestation rate was recorded on specimens of Timon princeps. This study is the first detailed investigation on ticks infesting reptiles in Turkey. To the best of our knowledge, these tick-host associations have never been documented in the literature.

  14. Biodiversity of microalgae in Western and Eastern Ghats, India.

    PubMed

    Suresh, A; Kumar, R Praveen; Dhanasekaran, D; Thajuddin, N

    2012-10-01

    The systematic study was conducted on the microalgal flora of Western Ghats and other parts of Eastern Ghats revealed a rich wetland algal resource for biotechnological exploration. The present study reveals with the diversity of microalgal flora in the region of Kodaikanal (10 degrees 14' N, 77 degrees 28' E), Gudalur (9 degrees 19'N 77 degrees 12'E), Agasthiyar falls (9 degrees 58'N, 78 degrees 10'E) and Kolli hills (10 degrees 12'N, 77 degrees 56'E) located in Western and Eastern Ghats of Tamilnadu, India collected in May 2011. In total, 97 species of micro algae belonging to three taxonomic groups were identified, of which 41 species belonging to Cyanophyceae, 38 species from Chlorophyceae and 18 species from Bacillariophyceae. The predominant species in Cyanophyceae were Aphanothece microscopica, Chroococcus minutus, Coelospharium dubium, Hydrococcus rivularism, Oscillatoria princeps, Nostoc muscorum, Nostoc puncteforme, Nostoc commune, Gleotricha gausii, Calothrix braunii, Rivellaria sp., Tolypothrix tenuis, Scytonema schmidtii, whereas in Chlorophyceae, Chlorella sp., Scenedesmus sp., Pediastrum duplex, Cosmarium consperum, Euastrum elagans, Micrasterias americana and in Bacillariophyceae, Navicula hallophyla, Rhophaldia gebrella, Fragellaria intermedia, Pinnularia virdis, Nitzchia palliate. Physicochemical nature of water samples were analyzed and correlated with the total microalgal diversity. Based on the correlation coefficient data, the micro algae showed positive relationship with dissolved oxygen, salinity, nutrients and negative relationship with temperature and turbidity. The species diversity index (H'), Species Richness (SR) and species evenness (J') were calculated and analyzed for microalgal population dynamic variation in the Western and Eastern Ghats.

  15. Contributions to the moss flora of Giresun Region (Sebinkarahisar and Alucra district).

    PubMed

    Ozdemir, T; Batan, N

    2008-08-15

    The aim of the study was to obtain knowledge on the moss flora of the Giresun Region-rather than to identify the entire range moss flora of the region. After the identification of 287 moss specimens collected from the research area between June and August in 2007 and 2008, total 85 taxa were defined. These taxa belong to 17 families and 37 genera of Bryopsida (Musci). Among them, 14 taxa -Hygroamblystegium irriguum Hedw., Rhynchostegium confertum (Dicks.) B. S. G., Rhynchostegium alpinum Huds. ex With., Bryum dichotomum Hedw., Bryum laevifilum Syed., Hygrohypnum smithii (Sw.) Broth., Grimmia decipiens (Schultz) Lindb., Grimmia tergestina Tomm. Ex Bruch and Schimp., Schistidium flaccidum (DeNot.) Ochyra., Schistidium platyphyllum (Mitt.) Kindb., Palustriella decipens (De Not.) Ochyra., Desmatodon latifolius (Hedw.) Brid., Phascum curvicolle Hedw., Syntrichia princeps (De Not.) Mitt. new for A4 grid square (40 degrees- 42' N, 38 degrees -42' E) which was adopted by Henderson. Thirty six taxa are new for Giresun Province. All taxa are new for study area. For every each taxon, the habitat pattern and distribution data are presented.

  16. 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

  17. Arthropod vectors and vector-borne bacterial pathogens in Yosemite National Park.

    PubMed

    Fleer, Katryna A; Foley, Patrick; Calder, Lee; Foley, Janet E

    2011-01-01

    Ticks, fleas, and vector-borne pathogens were surveyed in diverse small mammals in Yosemite National Park, California, from 2005 to 2007. A total of 450 unique captures of small mammals was collected during a 3-yr period and yielded 16 species of fleas and 10 species of ticks, including known vectors of Anaplasma phagocytophilum and Borrelia burgdorferi and plague. Serology was performed for A. phagocytophilum, spotted fever group Rickettsia spp., B. burgdorferi, and Yersinia pestis. A. phagocytophilum exposure was identified in 12.1% of all wild small mammals tested, with seropositive animals in 10 species, notably Belding's ground squirrels (Spermophilus beldingi), jumping mice (Zapus princeps), and voles (Microtus sp.). Spotted fever group Rickettsia spp. exposure was detected in 13.9% of all small mammals tested, with seropositive animals in eight species. Additionally, 37.0% of rodents in five species tested were seropositive for B. burgdorferi. No individuals were seropositive for Y. pestis. No animals were polymerase chain reaction positive for any pathogen tested. These results provide baseline data for future research and prediction of emerging vector-borne disease in Yosemite National Park, as well as adding to the known ranges and host species for tick and fleas in California.

  18. Species composition and distribution patterns of fishes captured by longlines on the Mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    Fossen, I.; Cotton, C. F.; Bergstad, O. A.; Dyb, J. E.

    2008-01-01

    During the 2004 MAR-ECO expedition to the Mid-Atlantic Ridge, the M/S Loran deployed longlines and caught a total of 8518 fish, representing 40 species and 17 families. The 59 longline sets were distributed across the ridge axis at depths ranging from 400 to 4300 m within two sub-areas, i.e. just north of the Azores archipelago and in the Charlie-Gibbs Fracture Zone (CGFZ). Overall, chondrichthyans dominated the catches and contributed nearly 60% in terms of both weight and numbers. This was mainly due to the dominance of Etmopterus princeps in both sub-areas. Multidimensional scaling using species-by-station data indicated an assemblage distribution related primarily to factors varying by depth and latitude. Grouping patterns of stations were not very pronounced, suggesting a gradual spatial change rather than abrupt changes in species composition by depth or latitude. Catch rates peaked at the shallower stations in the CGFZ sub-area, and generally decreased with depth. Relatively large individuals dominated, and the overall mean weight was 2.4 kg. Average fish weight was lower in the CGFZ sub-area than in the southern sub-area. No depth-related pattern was found.

  19. Anti-Inflammatory Effects of Artemisia Leaf Extract in Mice with Contact Dermatitis In Vitro and In Vivo.

    PubMed

    Yun, Chanyong; Jung, Youngchul; Chun, Wonjoo; Yang, Beodeul; Ryu, Junghyun; Lim, Chiyeon; Kim, Jung-Hoon; Kim, Hyungwoo; Cho, Su-In

    2016-01-01

    The leaves of Artemisia argyi Lev. et Vant. and A. princeps Pamp. are well known medicinal herbs used to treat patients in China, Japan, and Korea with skin problems such as eczema and itching, as well as abdominal pain and dysmenorrhoea. We investigated the anti-inflammatory effects of Artemisia leaf extract (ALE) using CD mice and Raw 264.7 cells. The effects of ALE on histopathological changes and cytokine production in ear tissues were assessed in mice with CD induced by 1-fluoro-2,4-dinitrobenzene (DNFB). Moreover, the anti-inflammatory effects on production levels of prostaglandin E2 (PGE2) and nitric oxide (NO) and expression levels of cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS) were investigated in Raw 264.7 cells. Topical application of ALE effectively prevented ear swelling induced by repeated DNFB application. ALE prevented epidermal hyperplasia and infiltration of immune cells and lowered the production of interferon- (IFN-) gamma (γ), tumour necrosis factor- (TNF-) alpha (α), and interleukin- (IL-) 6 in inflamed tissues. In addition, ALE inhibited expression of COX-2 and iNOS and production of NO and PGE2 in Raw 264.7 cells. These results indicate that Artemisia leaf can be used as a therapeutic agent for inflammatory skin diseases and that its anti-inflammatory effects are closely related to the inhibition of inflammatory mediator release from macrophages and inflammatory cytokine production in inflamed tissues.

  20. Phylogenetic correlates of extinction risk in mammals: species in older lineages are not at greater risk.

    PubMed

    Verde Arregoitia, Luis Darcy; Blomberg, Simon P; Fisher, Diana O

    2013-08-22

    Phylogenetic information is becoming a recognized basis for evaluating conservation priorities, but associations between extinction risk and properties of a phylogeny such as diversification rates and phylogenetic lineage ages remain unclear. Limited taxon-specific analyses suggest that species in older lineages are at greater risk. We calculate quantitative properties of the mammalian phylogeny and model extinction risk as an ordinal index based on International Union for Conservation of Nature Red List categories. We test for associations between lineage age, clade size, evolutionary distinctiveness and extinction risk for 3308 species of terrestrial mammals. We show no significant global or regional associations, and three significant relationships within taxonomic groups. Extinction risk increases for evolutionarily distinctive primates and decreases with lineage age when lemurs are excluded. Lagomorph species (rabbits, hares and pikas) that have more close relatives are less threatened. We examine the relationship between net diversification rates and extinction risk for 173 genera and find no pattern. We conclude that despite being under-represented in the frequency distribution of lineage ages, species in older, slower evolving and distinct lineages are not more threatened or extinction-prone. Their extinction, however, would represent a disproportionate loss of unique evolutionary history.

  1. Radiometric and geometric analysis of hyperspectral imagery acquired from an unmanned aerial vehicle

    DOE PAGES

    Hruska, Ryan; Mitchell, Jessica; Anderson, Matthew; ...

    2012-09-17

    During the summer of 2010, an Unmanned Aerial Vehicle (UAV) hyperspectral in-flight calibration and characterization experiment of the Resonon PIKA II imaging spectrometer was conducted at the U.S. Department of Energy’s Idaho National Laboratory (INL) UAV Research Park. The purpose of the experiment was to validate the radiometric calibration of the spectrometer and determine the georegistration accuracy achievable from the on-board global positioning system (GPS) and inertial navigation sensors (INS) under operational conditions. In order for low-cost hyperspectral systems to compete with larger systems flown on manned aircraft, they must be able to collect data suitable for quantitative scientific analysis.more » The results of the in-flight calibration experiment indicate an absolute average agreement of 96.3%, 93.7% and 85.7% for calibration tarps of 56%, 24%, and 2.5% reflectivity, respectively. The achieved planimetric accuracy was 4.6 meters (based on RMSE).« less

  2. Sub-seafloor bacterial community structures within massive sulfide deposits at the Southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Yamagishi, A.; Kato, S.; Moriya, O.; Urabe, T.

    2012-12-01

    Yet-uncharacterized sub-seafloor bacterial communities within massive sulfide deposits important for ocean elemental flux were investigated by 16S rRNA gene analysis. Shallow sub-seafloor drilling was performed in a deep-sea hydrothermal field (called Pika site) of the Southern Mariana Trough (SMT). The borehole length was 4.252 m and the length of the core sample obtained was 2,920 mm (¬68.7% recovery). The core sample mainly consisted of pyrite (FeS2), sphalerite (ZnS) and chalcopyrite (CuFeS2), and contained barite (BaSO4) as minor components. Three subsamples (upper, middle and lower) of the core sample were picked up from different depth points (0.77, 1.14, 2.37 mbsf). Bacterial 16S rRNA gene analysis was performed for the three subsamples. The community structures based on the detected clones were clearly different from one another. The dominant clone detected in each subsample was related to Gammaproteobacteria, Bacteroidetes and Ignavibacteria, or Nitrospirae, respectively. Many clones detected from the sub-seafloor massive sulfide deposits were similar to those from sulfide chimneys of inactive vents or basaltic lavas on the seafloor including SMT and other areas. Comparative analysis revealed the commonality and difference of the community structures with those in surrounding seafloor environments depending on the sampling depth.

  3. High-resolution magnetic signature of active hydrothermal systems in the back-arc spreading region of the southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Fujii, Masakazu; Okino, Kyoko; Honsho, Chie; Dyment, Jerome; Szitkar, Florent; Mochizuki, Nobutatsu; Asada, Miho

    2015-05-01

    High-resolution vector magnetic measurements were performed on five hydrothermal vent fields of the back-arc spreading region of the southern Mariana Trough using Shinkai 6500, a deep-sea manned submersible. A new 3-D forward scheme was applied that exploits the surrounding bathymetry and varying altitudes of the submersible to estimate absolute crustal magnetization. The results revealed that magnetic-anomaly-derived absolute magnetizations show a reasonable correlation with natural remanent magnetizations of rock samples collected from the seafloor of the same region. The distribution of magnetic-anomaly-derived absolute magnetization suggests that all five andesite-hosted hydrothermal fields are associated with a lack of magnetization, as is generally observed at basalt-hosted hydrothermal sites. Furthermore, both the Pika and Urashima sites were found to have their own distinct low-magnetization zones, which could not be distinguished in magnetic anomaly data collected at higher altitudes by autonomous underwater vehicle due to their limited extension. The spatial extent of the resulting low magnetization is approximately 10 times wider at off-axis sites than at on-axis sites, possibly reflecting larger accumulations of nonmagnetic sulfides, stockwork zones, and/or alteration zones at the off-axis sites.

  4. Molecular dietary analysis of two sympatric felids in the Mountains of Southwest China biodiversity hotspot and conservation implications

    PubMed Central

    Xiong, Mengyin; Wang, Dajun; Bu, Hongliang; Shao, Xinning; Zhang, Dan; Li, Sheng; Wang, Rongjiang; Yao, Meng

    2017-01-01

    Dietary information is lacking in most of small to mid-sized carnivores due to their elusive predatory behaviour and versatile feeding habits. The leopard cat (LPC; Prionailurus bengalensis) and the Asiatic golden cat (AGC; Catopuma temminckii) are two important yet increasingly endangered carnivore species in the temperate mountain forest ecosystem in Southwest China, a global biodiversity hotspot and a significant reservoir of China’s endemic species. We investigated the vertebrate prey of the two sympatric felids using faecal DNA and a next-generation sequencing (NGS)/metabarcoding approach. Forty vertebrate prey taxa were identified from 93 LPC and 10 AGC faecal samples; 37 taxa were found in the LPC diet, and 20 were detected in the AGC diet. Prey included 27 mammalian taxa, 11 birds, one lizard and one fish, with 73% (29/40) of the taxa assigned to the species level. Rodents and pikas were the most dominant LPC prey categories, whereas rodents, pheasant, fowl and ungulates were the main AGC prey. We also analysed the seasonal and altitudinal variations in the LPC diet. Our results provide the most comprehensive dietary data for these felids and valuable information for their conservation planning. PMID:28195150

  5. Absolute calibration of a variable attenuator using few-photon pulses.

    PubMed

    Levine, Zachary H; Glebov, Boris L; Pintar, Adam L; Migdall, Alan L

    2015-06-15

    We demonstrate the ability to calibrate a variable optical attenuator directly at the few-photon level using a superconducting Transition Edge Sensor (TES). Because of the inherent linearity of photon-number resolving detection, no external calibrations are required, even for the energy of the laser pulses, which ranged from means of 0.15 to 18 photons per pulse at the detector. To verify this method, calibrations were compared to an independent conventional calibration made at much higher photon fluxes using analog detectors. In all cases, the attenuations estimated by the two methods agree within their uncertainties.Our few-photon measurement determined attenuations using the Poisson-Influenced K-Means Algorithm (PIKA) to extract mean numbers of photons per pulse along with the uncertainties of these means. The robustness of the method is highlighted by the agreement of the two calibrations even in the presence of significant drifts in the optical power over the course of the experiment.Work of the United States Government. Not subject to copyright.

  6. Ecology and geographic distribution of Yersinia enterocolitica among livestock and wildlife in China.

    PubMed

    Liang, Junrong; Duan, Ran; Xia, Shengli; Hao, Qiong; Yang, Jinchuan; Xiao, Yuchun; Qiu, Haiyan; Shi, Guoxiang; Wang, Shukun; Gu, Wenpeng; Wang, Chunxiang; Wang, Mingliu; Tian, Kecheng; Luo, Longze; Yang, Meng; Tian, Huaiyu; Wang, Jiazheng; Jing, Huaiqi; Wang, Xin

    2015-07-09

    The results in this study show the prevalence of Yersinia enterocolitica varies in different animal species and regions of China. The highest prevalence is among pigs (12.91%), followed by dogs (9.80%), Ochotona curzoniae (plateau pica) (6.76%), chickens (4.50%), rodents (3.40%), cattle (2.78%) and sheep (0.89%). Pathogenic isolates comprised the majority of the Y. enterocolitica recovered from pigs (73.50%) and dogs (59.44%); whereas the nonpathogenic Y. enterocolitica made up most of poultry and wildlife recovered strains. A correlation analysis comparing the prevalence and geographic factors showed the isolation rate of Y. enterocolitica in pigs and dogs was negatively correlated with elevation (r=-0.50, P<0.05) and annual average air temperature (r=-0.43, P<0.05), but there was positive correlation with annual precipitation (r=0.43, P<0.05); conversely, the isolation rate from wildlife is positively correlated with elevation (r=0.3, P<0.05) contrary to the result seen in livestock. Twelve novel biotype 2 pathogenic Y. enterocolitica carried ail and ystB virulence genes, and one biotype 1A nonpathogenic strain positive with ail, ystB and ystA genes were isolated from Microtus fuscus (Qinghai vole) on plague foci of the Qinghai-Xizang plateau. The PFGE pattern K6GN11C30021 was predominant in pigs (44.25%) and patients (41.18%); K6GN11C30068 was predominant in dogs (40.16%). Animal isolates from the same region shared the same pattern (K6GN11C30021 and K6GN11C30012), indicating they may be from the same clone and arose through cross infection. Moreover, the identical PFGE pattern among local animals and diarrhea patients suggested that the animals may be the source of infections in these areas. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. [Species identification of Echinococcus isolates collected from canines and Tibetan foxes in Chengduo County, Qinghai Province].

    PubMed

    Feng, Kai; Huang, Fu-Qiang; Duo, Hong; Fu, Yong; Shen, Xiu-Ying; Peng, Mao; Li, Wei

    2013-06-01

    To identify Echinococcus isolates collected from Tibetan foxes(Vulpes ferrilata) and dogs in Chengduo county, Yushu Prefecture, Qinghai Province. Six Tibetan foxes and 6 Tibetan dogs died accidently. Small intestines were dissected from the animals. The adult tap-worms were collected by sedimentation technique. The worms were stained with borax carmine and observed under microscope. The isolates were identified initially by morphology and the infection intensity for each animal was calculated. Eight isolates of E. multilocularis and 2 isolates of E. shiquicus were selected for the extraction of total DNA. The mitochondrion DNA CO I gene was amplified with specific primers by PCR, then sequenced and analyzed. E. multilocularis and E. shiquicus were found. Two out of 6 Tibetan foxes were infected with E. multilocularis, the infection intensity was 1,640 and 839. One Tibetan fox was infected by E. shiquicus with an infection intensity of 833. Two Tibetan dogs were infected with E. multilocularis, and the infection intensity was 10,195 and 78, respectively. The obtained partial sequences of CO I gene were 450 bp. The CO I gene from 8 isolates of E. multilocularis shared 100% homology with the isolates collected from Tibetan dogs in Sichuan Province (Accession No. AB461417). The CO I gene from 2 isolates of E. shiquicus showed high sequence homology (99.2%) with the isolates collected from Ochotona curzoniae in Shiqu County, Sichuan Province(Accession No. AB159136). E. multilocularis and E. shiquicus have been identified in the small intestines of wild foxes, and E. multilocularis in Tibetan dogs.

  8. Microalgal diversity in relation to the physicochemical parameters of some Industrial sites in Mangalore, South India.

    PubMed

    Miranda, Jyothi; Krishnakumar, G

    2015-11-01

    This study is undertaken to understand the microalgal species composition, diversity, abundance and their association with the polluted sites of an industrial area. The microalgae and the wastewater samples collected from these sites were preserved and analysed using standard methods. One hundred and eight species of the microalgae, belonging to Cyanophyceae, Chlorophyceae, Euglenophyceae, Bacillariophyceace and Desmidaceae, were identified. Of these, the members of Cyanophyceae formed the dominant flora. It was observed that the family Oscillatoriaceae was the most diverse family. In this family, the most diverse genus was found to be the Oscillatoria, with 13 species. Further, the abundance of Oscillatoria princeps indicated that these species are tolerant to the pollution and therefore considered as the 'marker species' of the habitat. The abundance of the Cyanophyceae in these sites was found to be due to the favourable contents of the oxidizable organic matter and the presence of the nutrients, such as the nitrates and the phosphates, in abundance, with less dissolved oxygen. The lesser percentage of the Bacillariophyceae (14%), and the negligible number of the euglenoids (2%) indicated that the sites were rich in the inorganic pollutants and poor in the organic pollutants. The range of Shannon diversity indices was found between 2.10 and 3.50, while the dominance index was found between 0.03 and 0.14, the species evenness between 0.73 and 0.93 and the Margalef index between 1.8 and 6.3. The diversity indices indicated that there is light to moderate level of pollution in the studied sites, with moderate diversity level. The principal component analysis (PCA) of the physicochemical parameters identified the four possible groups, which were responsible for the data structure, explaining the 74% of the total variance of the data set. In the PCA performed using all the variables, the first principal component showed the positive correlation with the total

  9. Fermented rice bran prevents atopic dermatitis in DNCB-treated NC/Nga mice

    PubMed Central

    Saba, Evelyn; Lee, Chun Hee; Jeong, Da Hye; Lee, Kija; Kim, Tae-Hwan; Roh, Seong-Soo; Kim, Seung-Hyung; Rhee, Man Hee

    2016-01-01

    Abstract The fermentation of natural plants has a favorable effect on the functional and biological activities of living systems. These include anti-oxidative, anti-inflammatory, and anti-platelet aggregation activities. This is attributed to the chemical conversion of the parent plants to functional constituents, which show more potent biological activity. In our study, rice bran along with oriental medicinal plants (Angelicae gigantis, Cnidium officinale, Artemisia princeps, and Camellia sinensis) was fermented by Lactobacillus rhamnosus and Pichia deserticola (FRBE). We evaluated the effects of oral administration of FRBE on atopic dermatitis in 1-chloro-2,4-dinitrobenzene (DNCB)-treated NC/Nga mice. FRBE significantly ameliorated the macroscopic and microscopic appearance of skin lesions in DNCB-induced atopic dermatitis and reduced levels of serum immunoglobulin E and the differential white blood cell count. In addition, it reduced skin thickness compared to that of atopic dermatitis-affected skin. FRBE treatment also reduced mast cell incorporation in skin lesions of atopic dermatitis. The total cell number in dorsal skin tissue and the axillary lymph node increased following DNCB application, and this was normalized by FRBE treatment. Moreover, it decreased the levels of CD8+ helper T cells and Gr-1+/CD11b+ B cells in peripheral blood mononuclear cells and skin lesions in DNCB-induced atopic dermatitis. Using real-time polymerase chain reaction analysis, we demonstrated that FRBE significantly inhibited mRNA expression of cytokines (e.g., interleukin-5 and interleukin-13) and cyclooxygenase-2 in AD skin lesions. These results suggest that FRBE could be a valuable herbal remedy for the treatment of atopic dermatitis. PMID:27323667

  10. Cestodes from deep-water squaliform sharks in the Azores

    NASA Astrophysics Data System (ADS)

    Caira, Janine N.; Pickering, Maria

    2013-12-01

    The majority of our knowledge on marine tapeworms (cestodes) is limited to taxa that are relatively easy to obtain (i.e., those that parasitize shallower-water species). The invitation to participate in a deep-water research survey off the Condor seamount in the Azores offered the opportunity to gain information regarding parasites of the less often studied sharks of the mesopelagic and bathypelagic zone. All tapeworms (Platyhelminthes: Cestoda) found parasitizing the spiral intestine of squaliform shark species (Elasmobranchii: Squaliformes) encountered as part of this survey, as well as some additional Azorean sampling from previous years obtained from local fishermen are reported. In total, 112 shark specimens of 12 species of squaliform sharks representing 4 different families from depths ranging between 400 and 1290 m were examined. Cestodes were found in the spiral intestines from 11 of the 12 squaliform species examined: Deania calcea, D. cf. profundorum, D. profundorum, Etmopterus princeps, E. pusillus, E. spinax, Centroscyllium fabricii, Centroscymnus coelolepis, C. cryptacanthus, C. crepidater, and Dalatias licha. No cestodes were found in the spiral intestines of Centrophorus squamosus. Light microscopy and scanning electron microscopy revealed several potentially novel trypanorhynch and biloculated tetraphyllidean species. Aporhynchid and gilquiniid trypanorhynchs dominated the adult cestode fauna of Etmopterus and Deania host species, respectively, while larval phyllobothriids were found across several host genera, including, Deania, Centroscyllium, and Centroscymnus. These results corroborate previous findings that deep-water cestode faunas are relatively depauperate and consist primarily of trypanorhynchs of the families Gilquiniidae and Aporhynchidae and larval tetraphyllideans. A subset of specimens of most cestode species was preserved in ethanol for future molecular analysis to allow more definitive determinations of the identification of the

  11. Ultraviolet-C Light for Treatment of Candida albicans Burn Infection in Mice

    PubMed Central

    Dai, Tianhong; Kharkwal, Gitika B; Zhao, Jie; St. Denis, Tyler G; Wu, Qiuhe; Xia, Yumin; Huang, Liyi; Sharma, Sulbha K; d’Enfert, Christophe; Hamblin, Michael R

    2011-01-01

    Burn patients are at high risk of invasive fungal infections, which are a leading cause of morbidity, mortality, and related expense exacerbated by the emergence of drug resistant fungal strains. In this study, we investigated the use of UVC light (254-nm) for the treatment of Candida albicans infection in mouse third degree burns. In-vitro studies demonstrated that UVC could selectively kill the pathogenic yeast C. albicans compared to a normal keratinocyte cell line in a light exposure dependent manner. A mouse model of chronic C. albicans infection in non-lethal 3rd degree burns was developed. The C. albicans strain was stably transformed with a version of the Gaussia princeps luciferase gene that allowed real-time bioluminescence imaging of the progression of C. albicans infection. UVC treatment with a single exposure carried out on day 0 (30 minutes post-infection) gave an average 2.16-log10-unit (99.2%) loss of fungal luminescence when 2.92 J/cm2 UVC had been delivered, while UVC 24-hours post-infection gave 1.94-log10-unit (95.8%) reduction of fungal luminescence after 6.48 J/cm2. Statistical analysis demonstrated that UVC treatment carried out both on both day 0 and day 1 significantly reduced the fungal bioburden of infected burns. UVC was found to be superior to a topical antifungal drug, nystatin cream. UVC was tested on normal mouse skin and no gross damage was observed 24 hours after 6.48 J/cm2. DNA lesions (cyclobutane pyrimidine dimers) were observed by immunofluorescence in normal mouse skin immediately after a 6.48 J/cm2 UVC exposure, but the lesions were extensively repaired at 24-hours after UVC exposure. PMID:21208209

  12. Predation on larval suckers in the Williamson River Delta revealed by molecular genetic assays—A pilot study

    USGS Publications Warehouse

    Hereford, Danielle M.; Ostberg, Carl O.; Burdick, Summer M.

    2016-06-13

    Predation of endangered Lost River suckers (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) during larval egress to Upper Klamath Lake from the Williamson River is poorly understood but may be an important factor limiting recruitment into adult spawning populations. Native and non-native piscivores are abundant in nursery wetland habitat, but larval predation has not been directly studied for all species. Larvae lack hard body structures and digest rapidly in predator digestive systems. Therefore, traditional visual methods for diet analysis may fail to identify the extent of predation on larvae. The goals of this study were to (1) use quantitative polymerase chain reaction (qPCR) and single nucleotide polymorphism (SNP) assays developed for Lost River and shortnose suckers to assay predator stomach contents for sucker DNA, and (2) to assess our ability to use this technique to study predation. Predators were captured opportunistically during larval sucker egress. Concurrent feeding trials indicate that most predators—yellow perch (Perca flaverscens), fathead minnow (Pimephales promelas), blue chub (Gila coerulea), Klamath tui chub (Siphatales bicolor bicolor), Klamath Lake sculpin (Cottus princeps), slender sculpin (Cottus tenuis)—preyed on sucker larvae in the laboratory. However, sucker DNA was not detected in fathead minnow stomachs. Of the stomachs screened from fish captured in the Williamson River Delta, 15.6 percent of yellow perch contained sucker DNA. This study has demonstrated that the application of qPCR and SNP assays is effective for studying predation on larval suckers. We suggest that techniques associated with dissection or detection of sucker DNA from fathead minnow stomachs need improvement.

  13. Reporter enzyme inhibitor study to aid assembly of orthogonal reporter gene assays.

    PubMed

    Ho, Pei-i; Yue, Kimberley; Pandey, Pramod; Breault, Lyne; Harbinski, Fred; McBride, Aaron J; Webb, Brian; Narahari, Janaki; Karassina, Natasha; Wood, Keith V; Hill, Adam; Auld, Douglas S

    2013-05-17

    Reporter gene assays (RGAs) are commonly used to measure biological pathway modulation by small molecules. Understanding how such compounds interact with the reporter enzyme is critical to accurately interpret RGA results. To improve our understanding of reporter enzymes and to develop optimal RGA systems, we investigated eight reporter enzymes differing in brightness, emission spectrum, stability, and substrate requirements. These included common reporter enzymes such as firefly luciferase (Photinus pyralis), Renilla reniformis luciferase, and β-lactamase, as well as mutated forms of R. reniformis luciferase emitting either blue- or green-shifted luminescence, a red-light emitting form of Luciola cruciata firefly luciferase, a mutated form of Gaussia princeps luciferase, and a proprietary luciferase termed "NanoLuc" derived from the luminescent sea shrimp Oplophorus gracilirostris. To determine hit rates and structure-activity relationships, we screened a collection of 42,460 PubChem compounds at 10 μM using purified enzyme preparations. We then compared hit rates and chemotypes of actives for each enzyme. The hit rates ranged from <0.1% for β-lactamase to as high as 10% for mutated forms of Renilla luciferase. Related luciferases such as Renilla luciferase mutants showed high degrees of inhibitor overlap (40-70%), while unrelated luciferases such as firefly luciferases, Gaussia luciferase, and NanoLuc showed <10% overlap. Examination of representative inhibitors in cell-based assays revealed that inhibitor-based enzyme stabilization can lead to increases in bioluminescent signal for firefly luciferase, Renilla luciferase, and NanoLuc, with shorter half-life reporters showing increased activation responses. From this study we suggest strategies to improve the construction and interpretation of assays employing these reporter enzymes.

  14. [Bioaccumulation of heavy metals by the dominant plants growing in Huayuan manganese and lead/zinc mineland, Xiangxi].

    PubMed

    Yang, Sheng-Xiang; Tian, Qi-Jian; Liang, Shi-Chu; Zhou, Yao-Yu; Zou, Hui-Cheng

    2012-06-01

    Heavy metal pollution is a major environmental problem of mine wasteland. Finding out the tolerant plants, which can adapt to the local climate and the soil conditions, is the premise of vegetation restoration. An extensive vegetation survey and sampling were conducted in Huayuan Mn and Pb/Zn mineland, 76 species belonging to 69 genera and 39 families were recorded. The main dominant species and their associated soils were determined for heavy metal concentrations. The results showed that soil Pb, Zn and Cd levels exceeded the threshold levels of Class II of China Environmental Quality Standard for Soils, which suggested minesoils might be polluted by the three elements. The main dominant plants can adapt to the unfavorable edaphic conditions of mineland and were tolerant to heavy metals. There were great variations of metal uptake and accumulation among different plant species. They were classified into three types according to the metal concentrations in the plant shoots and roots: the accumulator, e. g. Camellia oleifera and Dicranopteris dichotoma, absorbed a large amount of heavy metals by the roots and transported to the shoots, which can be used to clean up the soils containing light to moderate toxic metal concentration and with high-value; the root compartment, e. g. Rubus tephrodes, R. corchorifolius, R. chroosepalus, Artemisia princeps and Pteridium aquilinum also absorbed a large amount of heavy metals but held in the roots; and the excluder, e. g. Miscanthus sinensis, Imperata cylindrica, Indocalamus tessellatus and Toddalia asiatica, absorbed less heavy metals than the accumulators. The root compartment and the excluder were more suitable for remediation of the mine wastelands with high heavy metal concentration, low-value and extensive area.

  15. Evolutionary Relationships among Primary Endosymbionts of the Mealybug Subfamily Phenacoccinae (Hemiptera: Coccoidea: Pseudococcidae) ▿

    PubMed Central

    Gruwell, Matthew E.; Hardy, Nate B.; Gullan, Penny J.; Dittmar, Katharina

    2010-01-01

    Mealybugs (Coccoidea: Pseudococcidae) are sap-sucking plant parasites that harbor bacterial endosymbionts within specialized organs. Previous studies have identified two subfamilies, Pseudococcinae and Phenacoccinae, within mealybugs and determined the primary endosymbionts (P-endosymbionts) of the Pseudococcinae to be Betaproteobacteria (“Candidatus Tremblaya princeps”) containing Gammaproteobacteria secondary symbionts. Here, the P-endosymbionts of phenacoccine mealybugs are characterized based on 16S rRNA from the bacteria of 20 species of phenacoccine mealybugs and four outgroup Puto species (Coccoidea: Putoidae) and aligned to more than 100 published 16S rRNA sequences from symbiotic and free-living bacteria. Phylogenetic analyses recovered three separate lineages of bacteria from the Phenacoccinae, and these are considered to be the P-endosymbionts of their respective mealybug hosts, with those from (i) the mealybug genus Rastrococcus belonging to the Bacteroidetes, (ii) the subterranean mealybugs, tribe Rhizoecini, also within Bacteroidetes, in a clade sister to cockroach endosymbionts (Blattabacterium), and (iii) the remaining Phenacoccinae within the Betaproteobacteria, forming a well-supported sister group to “Candidatus Tremblaya princeps.” Names are proposed for two strongly supported lineages: “Candidatus Brownia rhizoecola” for P-endosymbionts of Rhizoecini and “Candidatus Tremblaya phenacola” for P-endosymbionts of Phenacoccinae excluding Rastrococcus and Rhizoecini. Rates of nucleotide substitution among lineages of Tremblaya were inferred to be significantly faster than those of free-living Betaproteobacteria. Analyses also recovered a clade of Gammaproteobacteria, sister to the P-endosymbiont lineage of aphids (“Candidatus Buchnera aphidicola”), containing the endosymbionts of Putoidae, the secondary endosymbionts of pseudococcine mealybugs, and the endosymbionts of several other insect groups. PMID:20851962

  16. Variation in phenology of hibernation and reproduction in the endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus).

    PubMed

    Frey, Jennifer K

    2015-01-01

    Hibernation is a key life history feature that can impact many other crucial aspects of a species' biology, such as its survival and reproduction. I examined the timing of hibernation and reproduction in the federally endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus), which occurs across a broad range of latitudes and elevations in the American Southwest. Data from museum specimens and field studies supported predictions for later emergence and shorter active intervals in montane populations relative to lower elevation valley populations. A low-elevation population located at Bosque del Apache National Wildlife Refuge (BANWR) in the Rio Grande valley was most similar to other subspecies of Z. hudsonius: the first emergence date was in mid-May and there was an active interval of 162 days. In montane populations of Z. h. luteus, the date of first emergence was delayed until mid-June and the active interval was reduced to ca 124-135 days, similar to some populations of the western jumping mouse (Z. princeps). Last date of immergence into hibernation occurred at about the same time in all populations (mid to late October). In montane populations pregnant females are known from July to late August and evidence suggests that they have a single litter per year. At BANWR two peaks in reproduction were expected based on similarity of active season to Z. h. preblei. However, only one peak was clearly evident, possibly due to later first reproduction and possible torpor during late summer. At BANWR pregnant females are known from June and July. Due to the short activity season and geographic variation in phenology of key life history events of Z. h. luteus, recommendations are made for the appropriate timing for surveys for this endangered species.

  17. Antioxidant activity of various teas against free radicals and LDL oxidation.

    PubMed

    Ohmori, Reiko; Iwamoto, Tamami; Tago, Motomi; Takeo, Tadakazu; Unno, Tomonori; Itakura, Hiroshige; Kondo, Kazuo

    2005-08-01

    Tea is a widely consumed beverage throughout the world. We assessed the antioxidant activity of six teas, including the aqueous extracts of green tea and oolong tea (Camellia sinensis), tochu (Eucommia ulmoides), Gymnema sylvestre, Japanese mugwort (Artemisia princeps), and barley (Hordeum vulgare), against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and LDL oxidation, and examined the association of LDL oxidizability with the plasma catechin levels in 10 healthy volunteers with a single dose of 5 g green tea powder. In vitro, the inhibitory effects of DPPH radicals and LDL oxidation were found to be strongest in the extract of green tea and weakest in that of barley. After the ingestion of green tea powder, the lag time increased from basal 52.2 +/- 4.1 to 60.3 +/- 4.2 min at 1 h and 59.5 +/- 4.1 min at 2 h, and then returned to the baseline lag time (51.9 +/- 1.4 at 4 h and 52.1 +/- 4.7 min at 6 h). Regarding the plasma catechin levels, epigallocatechingallate and epicatechingallate significantly increased from basal 3.7 +/- 1.3 and 0.8 +/- 0.8 ng/mL to 65.7 +/- 11.6 and 54.6 +/- 12.6 ng/mL at 1 h, and 74.4 +/- 18.6 and 49.4 +/- 7.1 ng/mL at 2 h, respectively. Green tea therefore showed the strongest antioxidant activity among the six different teas, and the inhibitory effects of green tea on LDL oxidation depended on the plasma catechin levels.

  18. Rapid construction and screening of artificial microRNA systems in Chlamydomonas reinhardtii.

    PubMed

    Hu, Jinlu; Deng, Xuan; Shao, Ning; Wang, Gaohong; Huang, Kaiyao

    2014-09-01

    The unicellular green algae Chlamydomonas reinhardtii is a classic model for the study of flagella/cilia and photosynthesis, and it has recently been exploited for producing biopharmaceuticals and biofuel. Due to the low frequency of homologous recombination, reverse genetic manipulation in Chlamydomonas relies mainly on miRNA- and siRNA-based knockdown methods. However, the difficulty in constructing artificial miRNA vectors, laborious screening of knockdown transformants, and undesired epigenetic silencing of exogenous miRNA constructs limit their application. We have established a one-step procedure to construct an artificial miRNA precursor by annealing eight oligonucleotides of approximately 40 nucleotides. In the final construct, the Gaussia princeps luciferase gene (G-Luc) is positioned between the promoter and the artificial miRNA precursor so that knockdown strains may quickly be screened by visualizing luciferase luminescence using a photon-counting camera. Furthermore, the luciferase activity of transformants correlates with the knockdown level of two test target proteins: the chloroplast protein VIPP1 (vesicle inducing protein in plastids 1) and the flagellar protein CDPK3 (calcium-dependent protein kinase 3). Adding an intron from RBCS2 (ribulose bisphosphate carboxylase/oxygenase small subunit 2) to the miRNA construct enhanced both the luciferase activity and the miRNA knockdown efficiency. A second miRNA vector incorporated the promoter of the nitrate reductase gene to allow inducible expression of the artificial miRNA. These vectors will facilitate application of the artificial miRNA and provide tools for studying the mechanism of epigenetics in Chlamydomonas, and may also be adapted for use in other model organisms.

  19. Selenocystamine improves protein accumulation in chloroplasts of eukaryotic green algae.

    PubMed

    Ferreira-Camargo, Livia S; Tran, Miller; Beld, Joris; Burkart, Michael D; Mayfield, Stephen P

    2015-12-01

    Eukaryotic green algae have become an increasingly popular platform for recombinant proteins production. In particular, Chlamydomonas reinhardtii, has garnered increased attention for having the necessary biochemical machinery to produce vaccines, human antibodies and next generation cancer targeting immunotoxins. While it has been shown that chloroplasts contain chaperones, peptidyl prolylisomerases and protein disulfide isomerases that facilitate these complex proteins folding and assembly, little has been done to determine which processes serve as rate-limiting steps for protein accumulation. In other expression systems, as Escherichia coli, Chinese hamster ovary cells, and insect cells, recombinant protein accumulation can be hampered by cell's inability to fold the target polypeptide into the native state, resulting in aggregation and degradation. To determine if chloroplasts' ability to oxidize proteins that require disulfide bonds into a stable conformation is a rate-limiting step of protein accumulation, three recombinant strains, each expressing a different recombinant protein, were analyzed. These recombinant proteins included fluorescent GFP, a reporter containing no disulfide bonds; Gaussia princeps luciferase, a luminescent reporter containing disulfide bonds; and an immunotoxin, an antibody-fusion protein containing disulfide bonds. Each strain was analyzed for its ability to accumulate proteins when supplemented with selenocystamine, a small molecule capable of catalyzing the formation of disulfide bonds. Selenocystamine supplementation led to an increase in luciferase and immunotoxin but not GFP accumulation. These results demonstrated that selenocystamine can increase the accumulation of proteins containing disulfide bonds and suggests that a rate-limiting step in chloroplast protein accumulation is the disulfide bonds formation in recombinant proteins native structure.

  20. Multidimensional effects of biologically synthesized silver nanoparticles in Helicobacter pylori, Helicobacter felis, and human lung (L132) and lung carcinoma A549 cells

    NASA Astrophysics Data System (ADS)

    Gurunathan, Sangiliyandi; Jeong, Jae-Kyo; Han, Jae Woong; Zhang, Xi-Feng; Park, Jung Hyun; Kim, Jin-Hoi

    2015-02-01

    Silver nanoparticles (AgNPs) are prominent group of nanomaterials and are recognized for their diverse applications in various health sectors. This study aimed to synthesize the AgNPs using the leaf extract of Artemisia princeps as a bio-reductant. Furthermore, we evaluated the multidimensional effect of the biologically synthesized AgNPs in Helicobacter pylori, Helicobacter felis, and human lung (L132) and lung carcinoma (A549) cells. UV-visible (UV-vis) spectroscopy confirmed the synthesis of AgNPs. X-ray diffraction (XRD) indicated that the AgNPs are specifically indexed to a crystal structure. The results from Fourier transform infrared spectroscopy (FTIR) indicate that biomolecules are involved in the synthesis and stabilization of AgNPs. Dynamic light scattering (DLS) studies showed the average size distribution of the particle between 10 and 40 nm, and transmission electron microscopy (TEM) confirmed that the AgNPs were significantly well separated and spherical with an average size of 20 nm. AgNPs caused dose-dependent decrease in cell viability and biofilm formation and increase in reactive oxygen species (ROS) generation and DNA fragmentation in H. pylori and H. felis. Furthermore, AgNPs induced mitochondrial-mediated apoptosis in A549 cells; conversely, AgNPs had no significant effects on L132 cells. The results from this study suggest that AgNPs could cause cell-specific apoptosis in mammalian cells. Our findings demonstrate that this environmentally friendly method for the synthesis of AgNPs and that the prepared AgNPs have multidimensional effects such as anti-bacterial and anti-biofilm activity against H. pylori and H. felis and also cytotoxic effects against human cancer cells. This report describes comprehensively the effects of AgNPs on bacteria and mammalian cells. We believe that biologically synthesized AgNPs will open a new avenue towards various biotechnological and biomedical applications in the near future.

  1. Field evaluation of traditionally used plant-based insect repellents and fumigants against the malaria vector Anopheles darlingi in Riberalta, Bolivian Amazon.

    PubMed

    Moore, Sarah J; Hill, Nigel; Ruiz, Carmen; Cameron, Mary M

    2007-07-01

    Inexpensive insect repellents may be needed to supplement the use of impregnated bed-nets in the Amazon region, where the primary malaria vector, Anopheles darlingi (Root), is exophilic and feeds in the early evening. Three plants that are traditionally used to repel mosquitoes in Riberalta, Bolivian Amazon, were identified by focus group, and then they were tested against An. darlingi as well as Mansonia indubitans (Dyar & Shannon)/Mansonia titillans (Walker). Cymbopogon citratus (Staph), Guatemalan lemongrass, essential oil at 25% was used as a skin repellent, and it provided 74% protection for 2.5 h against predominantly An. darlingi and 95% protection for 2.5 h against Mansonia spp. Attalea princeps (name not verified) husks, burned on charcoal in the traditional way provided 35 and 51% protection against An. darlingi and Mansonia spp., respectively. Kerosene lamps, often used to light rural homes, were used as a heat source to volatilize 100% Mentha arvensis (Malinv ex. Bailey) essential oil, and they reduced biting by 41% inside traditional homes against Mansonia spp., although they were ineffective outdoors against An. darlingi. All three plant-based repellents provided significant protection compared with controls. Plant-based repellents, although less effective than synthetic alternatives, were shown by focus groups to be more culturally acceptable in this setting, in particular para-menthane-3, 8, idol derived from lemon eucalyptus, Corymbia citriodora (Hook). Plant-based repellents have the potential to be produced locally and therefore sold more cheaply than synthetic commercial repellents. Importantly, their low cost may encourage user compliance among indigenous and marginalized populations.

  2. Arterial supply of the thumb: Systemic review.

    PubMed

    Miletin, J; Sukop, A; Baca, V; Kachlik, D

    2017-10-01

    We offer a complete systemic review of the anatomy of arteries of the thumb, including their sources in the first web space. Eleven studies were selected from the PubMed, Medline, Embase, Scopus and Ovid databases. Data about each artery of the thumb were obtained; in particular, the incidence and dominance of each of these arteries were calculated. The ulnopalmar digital artery of the thumb (UPDAT) was found in 99.63%, the radiopalmar digital artery of the thumb (RPDAT) in 99.26%, the ulnodorsal digital artery of the thumb (UDDAT) in 83.39%, and the radiodorsal digital artery of the thumb (RDDAT) in 70.38%. The sources for the thumb arteries are the first palmar metacarpal artery (for UPDAT in 63.15%, for RPDAT in 78.88%, for UDDAT in 56.95% and for RDDAT in 41.48%), the first dorsal metacarpal artery (for UPDAT in 20.54%, for RPDAT 2.53%, for UDDAT in 20.62%, and for RDDAT in 4.81%) and the superficial palmar arch, either complete or incomplete (for UPDAT in 25.57%, for RPDAT in 23.04%, for UDDAT in 0%, and for RDDAT in 5.19%). The dominant source could be identified in 88.2% of cases: the first palmar metacarpal artery (66.2%), the first dorsal metacarpal artery (15.5%) and the superficial palmar arch, complete or incomplete (8.2%). Four arteries usually supply the thumb. Any artery in the first web space can be a source for the thumb arteries. We propose a new classification of the arteries of the hand, dividing them into three systems (superficial palmar, deep palmar and dorsal system), and suggest that the term "princeps pollicis artery" be reconsidered and systemic anatomical terms of the thumb arteries preferred. Clin. Anat. 30:963-973, 2017. ©2017 Wiley-Liss, Inc. © 2017 Wiley Periodicals, Inc.

  3. Candida albicans Biofilm Development on Medically-relevant Foreign Bodies in a Mouse Subcutaneous Model Followed by Bioluminescence Imaging

    PubMed Central

    Kucharíková, Soňa; Vande Velde, Greetje; Himmelreich, Uwe; Van Dijck, Patrick

    2015-01-01

    Candida albicans biofilm development on biotic and/or abiotic surfaces represents a specific threat for hospitalized patients. So far, C. albicans biofilms have been studied predominantly in vitro but there is a crucial need for better understanding of this dynamic process under in vivo conditions. We developed an in vivo subcutaneous rat model to study C. albicans biofilm formation. In our model, multiple (up to 9) Candida-infected devices are implanted to the back part of the animal. This gives us a major advantage over the central venous catheter model system as it allows us to study several independent biofilms in one animal. Recently, we adapted this model to study C. albicans biofilm development in BALB/c mice. In this model, mature C. albicans biofilms develop within 48 hr and demonstrate the typical three-dimensional biofilm architecture. The quantification of fungal biofilm is traditionally analyzed post mortem and requires host sacrifice. Because this requires the use of many animals to perform kinetic studies, we applied non-invasive bioluminescence imaging (BLI) to longitudinally follow up in vivo mature C. albicans biofilms developing in our subcutaneous model. C. albicans cells were engineered to express the Gaussia princeps luciferase gene (gLuc) attached to the cell wall. The bioluminescence signal is produced by the luciferase that converts the added substrate coelenterazine into light that can be measured. The BLI signal resembled cell counts obtained from explanted catheters. Non-invasive imaging for quantifying in vivo biofilm formation provides immediate applications for the screening and validation of antifungal drugs under in vivo conditions, as well as for studies based on host-pathogen interactions, hereby contributing to a better understanding of the pathogenesis of catheter-associated infections. PMID:25651138

  4. Infection dynamics of coexisting beta- and gammaproteobacteria in the nested endosymbiotic system of mealybugs.

    PubMed

    Kono, Marie; Koga, Ryuichi; Shimada, Masakazu; Fukatsu, Takema

    2008-07-01

    We investigated the infection dynamics of endosymbiotic bacteria in the developmental course of the mealybugs Planococcus kraunhiae and Pseudococcus comstocki. Molecular phylogenetic analyses identified a betaproteobacterium and a gammaproteobacterium from each of the mealybug species. The former bacterium was related to the beta-endosymbionts of other mealybugs, i.e., "Candidatus Tremblaya princeps," and formed a compact clade in the Betaproteobacteria. Meanwhile, the latter bacterium was related to the gamma-endosymbionts of other mealybugs but belonged to distinct clades in the Gammaproteobacteria. Whole-mount in situ hybridization confirmed the peculiar nested formation in the endosymbiotic system of the mealybugs: the beta-endosymbiont cells were present in the cytoplasm of the bacteriocytes, and the gamma-endosymbiont cells were located in the beta-endosymbiont cells. In nymphal and female development, a large oval bacteriome consisting of a number of bacteriocytes was present in the abdomen, wherein the endosymbionts were harbored. In male development, strikingly, the bacteriome progressively degenerated in prepupae and pupae and became almost unrecognizable in adult males. In the degeneration process, the gamma-endosymbionts disappeared more rapidly than the beta-endosymbionts did. Quantitative PCR analyses revealed that (i) the population dynamics of the endosymbionts in female development reflected the reproductive activity of the insects, (ii) the population dynamics of the endosymbionts were strikingly different between female development and male development, (iii) the endosymbiont populations drastically decreased in male development, and (iv) the gamma-endosymbiont populations decreased more rapidly than the beta-endosymbiont populations in male development. Possible mechanisms underlying the uncoupled regulation of the beta- and gamma-endosymbiont populations are discussed in relation to the establishment and evolution of this unique prokaryote

  5. Nocardioides endophyticus sp. nov. and Nocardioides conyzicola sp. nov., isolated from herbaceous plant roots.

    PubMed

    Han, Ji-Hye; Kim, Tae-Su; Joung, Yochan; Kim, Mi Na; Shin, Kee-Sun; Bae, Taeok; Kim, Seung Bum

    2013-12-01

    Two Gram-stain-positive, non-motile, non-spore-forming, rod-shaped actinobacterial strains were isolated from the surface-sterilized roots of mugwort (Artemisia princeps) and horse-weed (Conyza canadensis), and subjected to taxonomic characterization. 16S rRNA gene sequence analysis indicated that the isolates, designated MWE 3-5(T) and HWE 2-02(T), should be placed in the genus Nocardioides of the family Nocardioidaceae. The strains were closely related to Nocardioides hankookensis DS-30(T), which exhibited 16S rRNA gene sequence similarity values of 97.99 and 99.09 % with strains MWE 3-5(T) and HWE 2-02(T), respectively. The genome relatedness of N. hankookensis DS-30(T) with strain MWE 3-5(T) was 35.8 %, and that with strain HWE 2-02(T) was 36.4 %, whereas that between the two isolates was 43.2 %. Strains MWE 3-5(T) and HWE 2-02(T) possessed MK-8(H4) as the major isoprenoid quinone, and ll-diaminopimelic acid in the cell-wall peptidoglycan. The main fatty acids were iso-C16 : 0, iso-C17 : 0 and C18 : 1ω9c for strain MWE 3-5(T) and iso-C16 : 0, 10-methyl C18 : 0 and C18 : 1ω9c for strain HWE 2-02(T). Based on phenotypic, genotypic and phylogenetic studies, the following two novel species are proposed: Nocardioides endophyticus sp. nov. (type strain, MWE 3-5(T) = KCTC 29122(T) = JCM 18532(T)) and Nocardioides conyzicola sp. nov. (type strain, HWE 2-02(T) = KCTC 29121(T) = JCM 18531(T)).

  6. Variation in phenology of hibernation and reproduction in the endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus)

    PubMed Central

    2015-01-01

    Hibernation is a key life history feature that can impact many other crucial aspects of a species’ biology, such as its survival and reproduction. I examined the timing of hibernation and reproduction in the federally endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus), which occurs across a broad range of latitudes and elevations in the American Southwest. Data from museum specimens and field studies supported predictions for later emergence and shorter active intervals in montane populations relative to lower elevation valley populations. A low-elevation population located at Bosque del Apache National Wildlife Refuge (BANWR) in the Rio Grande valley was most similar to other subspecies of Z. hudsonius: the first emergence date was in mid-May and there was an active interval of 162 days. In montane populations of Z. h. luteus, the date of first emergence was delayed until mid-June and the active interval was reduced to ca 124–135 days, similar to some populations of the western jumping mouse (Z. princeps). Last date of immergence into hibernation occurred at about the same time in all populations (mid to late October). In montane populations pregnant females are known from July to late August and evidence suggests that they have a single litter per year. At BANWR two peaks in reproduction were expected based on similarity of active season to Z. h. preblei. However, only one peak was clearly evident, possibly due to later first reproduction and possible torpor during late summer. At BANWR pregnant females are known from June and July. Due to the short activity season and geographic variation in phenology of key life history events of Z. h. luteus, recommendations are made for the appropriate timing for surveys for this endangered species. PMID:26290794

  7. [The examination of men's wits by Juan Huarte de San Juan, and the dawn of the neurobiology of intelligence in the Spanish renaissance].

    PubMed

    Martín-Araguz, A; Bustamante-Martínez, C

    The Spanish renaissance doctor Juan Huarte de San Juan (1529-1588) was the author of a unique and immortal work, The Examination of Men's Wits, the edition princeps of which was printed in Baeza in 1575. Since then it has been reprinted at least 80 times and translated into seven languages, which makes it the most influential Spanish contribution to medicine ever published. In this paper we review the unjustly little-known figure of Huarte as the founder of Neuropsychology, and we also analyse his works from a historical and neuroscientific point of view. Huarte's writings deal with the problem of the organic relations between the brain and understanding, and accept the possible influences exerted by temper on the will within the field of the Neurobiology of Intelligence. Thus, over four centuries ago Huarte became the founder of Differential or Physiological Psychology, Neuropsychology, Eugenics and Career Guidance. Huarte's work not only played a fundamental role in the history and development of the body of neuroscientific knowledge, but has also been a clear (although not always cited) influence on scientists, philosophers and men of letters such as Alarcón, Bacon, Cabanis, Cervantes (whose Don Quixote was inspired by him), Charron, Chomsky, Gall, Goethe, Hume, Kant, Kretchmer, Lessing, Lope de Vega, Montaigne, Montesquieu, Nietzsche, Quevedo, Rousseau, Schopenhauer, Thomasius, Tirso de Molina and Ziegler. In the middle of the 16th century, Huarte and his Examination of Men's Wits, together with the works of the naturalist philosophers Gómez Pereira (Antoniana Margarita, 1554) and Miguel Sabuco (New Philosophy, 1587), constituted the prestigious triumvirate of Spanish Renaissance scholars who, for the first time in history, contemplated the workings of the brain from a point of view that had more to do with science than the supernatural.

  8. The Purisima Formation at Capitola Beach, Santa Cruz County, CA: A Deeper Examination of Pliocene Fossils

    NASA Astrophysics Data System (ADS)

    White, L. D.; Brooks, K.; Chen, R.; Chen, T.; James, T.; Gonzales, J.; Schumaker, D.; Williams, D.

    2005-12-01

    Fossil samples from the Pliocene Purisima Formation at Capitola Beach in Santa Cruz County, CA were collected in July-August 2005. The Purisima Formation composes the bulk of the cliffs exposed at Capitola Beach and a rich assemblage of well-preserved fossils occur in gray to brown sandstone and siltstone. Erosion of the cliff face averages 0.3 meter/year and fresh cliff falls in the winter and spring months of 2005 provided an excellent opportunity to resample the Capitola Beach section of the Purisima Formation previously documented by Perry (1988). Organisms were identified from information in Perry (1988) and were compared with collections at the California Academy of Sciences. The most abundant fossils found are from the phylum Mollusca, classes Bivalvia and Gastropoda. Abundant bivalve taxa are: Anadara trilineata, Clinocardium meekianum, Macoma sp., Protothaca staleyi, and Tresus pajaroanus. Also common are the gastropods, Calyptraea fastigata, Crepdiula princeps, Mitrella gausapata, Nassarius grammatus, Nassarius californianus, Natica clausa, and Olivella pedroana. Less common invertebrate fossils are from the phylum Echinodermata ( Dendraster sp., the extinct fossil sand dollar) and from the phylum Arthropoda ( Crustacea), crab fragments ( Cancer) and barnacles ( Balanus). Because numerous fossils are concentrated as fragments in shell beds, Norris (1986) and Perry (1988) believe many were redeposited as storm beds during strong current events that promoted rapid burial. In contrast, whale and other vertebrate bones are common in certain horizons and their presence may be related to the conditions that promoted phosphate mineralization, such as episodes of low sedimentation rates and prolonged exposure on the seafloor (Föllmi and Garrison, 1991). The bone beds, together with the rich infaunal and epifaunal invertebrate assemblages, represent a community of invertebrate organisms that thrived in a shallow marine sea during the Pliocene epoch, approximately

  9. Topsoil, ripping, and herbicides influence tree survival and growth on coal minesoil after nine years

    SciTech Connect

    Kost, D.A.; Brown, J.H.; Vimmerstedt, J.P. |

    1998-12-31

    On reclaimed coal surface mines trees are stressed by soil compaction, herbaceous competition, and animal damage. The authors tested treatments to modify soils and herbaceous competition in a split-split-plot experiment on calcareous minesoils in southeastern Ohio. They measured tree survival and growth as affected by minesoil surface (standard graded topsoil, ripped topsoil, graded overburden) and herbicide applications (type, rate, and frequency). Green ash, silver maple, European alder, black pine, eastern white pine, and Virginia pine were planted into a grass/legume ground cover seeded 18 months earlier. Herbicides were applied over the trees at two rates and two frequencies (first year only, two consecutive years) for all species except Virginia pine. After nine years, only green ash (95%) and black pine (48%) had adequate survival. Silver maple (16%), alder (7%), Virginia pine (6%) and white pine (<1%) had low survival by the fifth year. Black pine survived better on standard topsoil (60%) than on graded overburden (37%) and was 43% taller on both topsoils (165 or 168 cm total height) than on graded overburden (116 cm). Green ash height varied significantly on all soil surfaces (172 cm on ripped topsoil, 136 cm on standard topsoil, 102 cm on graded overburden). Survival on herbicide treated plots was greater than on untreated controls only for Virginia pine sprayed with Princep or Oust and for silver maple sprayed with Stomp, but both species had less than 25% survival even when treated by these herbicides. Green ash survival decreased with both rates of Oust and with increasing frequency of Oust. Green ash height was increased on average of 19% by either rate of Dowpon or Surflan. Longer term tree growth was benefited more by topsoil replacement and ripping than by herbicide treatments.

  10. Candida albicans biofilm development on medically-relevant foreign bodies in a mouse subcutaneous model followed by bioluminescence imaging.

    PubMed

    Kucharíková, Soňa; Vande Velde, Greetje; Himmelreich, Uwe; Van Dijck, Patrick

    2015-01-27

    Candida albicans biofilm development on biotic and/or abiotic surfaces represents a specific threat for hospitalized patients. So far, C. albicans biofilms have been studied predominantly in vitro but there is a crucial need for better understanding of this dynamic process under in vivo conditions. We developed an in vivo subcutaneous rat model to study C. albicans biofilm formation. In our model, multiple (up to 9) Candida-infected devices are implanted to the back part of the animal. This gives us a major advantage over the central venous catheter model system as it allows us to study several independent biofilms in one animal. Recently, we adapted this model to study C. albicans biofilm development in BALB/c mice. In this model, mature C. albicans biofilms develop within 48 hr and demonstrate the typical three-dimensional biofilm architecture. The quantification of fungal biofilm is traditionally analyzed post mortem and requires host sacrifice. Because this requires the use of many animals to perform kinetic studies, we applied non-invasive bioluminescence imaging (BLI) to longitudinally follow up in vivo mature C. albicans biofilms developing in our subcutaneous model. C. albicans cells were engineered to express the Gaussia princeps luciferase gene (gLuc) attached to the cell wall. The bioluminescence signal is produced by the luciferase that converts the added substrate coelenterazine into light that can be measured. The BLI signal resembled cell counts obtained from explanted catheters. Non-invasive imaging for quantifying in vivo biofilm formation provides immediate applications for the screening and validation of antifungal drugs under in vivo conditions, as well as for studies based on host-pathogen interactions, hereby contributing to a better understanding of the pathogenesis of catheter-associated infections.

  11. Discovery and drilling of on- and off-axis hydrothermal sites in backarc spreading center of southern Mariana Trough, Western Pacific

    NASA Astrophysics Data System (ADS)

    Urabe, T.; Ishibashi, J.; Maruyama, A.; Marumo, K.; Seama, N.; Utsumi, M.

    2004-12-01

    The Mariana Trough is an actively spreading backarc basin that is located along the eastern margin of Philippine Sea Plate. GPS monitoring indicates that the rate of spreading is about 45 mm/yr in the southern section (Kato et al., 2003). No transform fault offsets exist despite significant changes in the trend of the spreading center. Fryer et al. (1998) pointed out the close proximity of submarine arc volcanoes to the spreading center and tectonic fabric that is at a high angle to the trend of the spreading center on the eastern flank. Three hydrothermal sites were discovered along such tectonic lineament in southern Mariana Trough (12o55-57'N, 143o37-39'E). On-axis site (so-called Fryer site, depth: 2,850 m) consists of a hydrothermal mound about 20 m in diameter that develops on pillow lava of a segment center of the spreading axis. The segment is characterized by highly variable rock composition (up to 68% SiO2). Repeated temperature measurements revealed rapid cooling of the hydrothermal system from 240oC in April 2003, through 112oC in October 2003 to 69oC in March 2004. On the other hand, two off-axis sites seem to have longevity of life: The Archaean site which locates about 2 km off-axis on the eastern (arc side) skirt is characterized by its huge sulfide spire; 50 m in height and 20 m in diameter. It is composed of pyrite, chalcopyrite and sphalerite, and is emanating hydrothermal fluids up to 220oC. In the third site (Pika site), active black smokers (max. temp. = 330oC), numerous dead chimneys and sulfide mounds were found on a basaltic seamount about 5 km off-axis. These lines of evidence support the idea of Fryer et al. (1998) that the backarc magma is replenished by arc/off-axis magma along the tectonic lineation. The first and third sites been drilled and cased using a tethered, submarine rock-drill system BMS (Benthic Multi-coring System) on-board the R/V Hakurei-Maru # 2 as a part of Archaean Park Project*. Rocks from two holes (7.5 m and 4.1 m

  12. Topographic characteristics of four hydrothermal sites at the southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Okino, K.; Asada, M.

    2011-12-01

    A high-resolution bathymetry is one of the essential information to clarify the broad overview of hydrothermal system. We here represent the geomorphological characteristics of four hydrothermal sites at the southern Mariana Trough, using the near-bottom swath mapping data that can produce 2 m grid spacing collected by SEABAT7125AUV on AUV Urashima during YK09-08 cruise, and dive observation data acquired by Shinkai6500 during YK10-11 cruise. In the study area, near 12°57'N, 143°37'E, the hydrothermal sites (Snail and Yamanaka site, Archaean site, Pika site) are located just on the active backarc spreading axis, the eastern foot of the axial high, and the top of an off-axis knoll about 5 km from the axis, respectively (e.g., Ishibashi et al., 2004; Kakegawa et al., 2008; Urabe et al., 2004), and these are aligned roughly perpendicular to the spreading axis. Each AUV survey was conducted within the area of about 1 km x 2 km. On-axis area is divided into two subareas based on their geological characteristics: 1) the area strongly deformed by many faults and fissures, and 2) the area with several mounds cut by fissures. The two hydrothermal sites (Snail and Yamanaka site) are distributed along the fissure in the latter area. The strike of faults and fissures and distribution of the mounds are approximately parallel to the spreading axis. The height of the mounds ranges from 5 to 30 m, and its diameter is 250 to 320 m. They have comparatively flat tops and gentle slopes, indicating dome like morphology. The Archean site is located on the top of single mound. The mound is conical in shape, whose diameter is 250 to 300 m and its height is 50 to 100 m. Numerous ridge lines and several chimney-like structures (up to about 6 m high) are formed on the top and slope of the mound. The age of the mound is younger than that of surrounding rugged seafloor because of the undeformed mound morphology. The off-axis knoll consists of two peaks. The Pika site is located on its

  13. Chemical characteristics of magma and related seafloor sulfide deposits on back-arc spreading center and off-ridge volcanoes in Southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Urabe, T.; Kanamori, S.; Ishibashi, J.; Kentaro, K.; Sato, H.; Kato, S.; Toyoda, S.

    2012-12-01

    The back-arc basalt in Mariana Trough is characterized by fluid-dominated components (Stolper and Newman, 1994). They suggested that the H2O-enriched magma of the Mariana Trough is formed as melting mixture between MORB-type mantle source and H2O-rich component which is likely to be derived from the subducting slab. Four active and one inactive hydrothermal sites were found within a distance of 5 km in Southern Mariana Trough; that is, Snail site (12o57.19'N, 143o37.16'E, depth:2861m) and Yamanaka site (12o56.64'N, 143o36.80'E, depth: 2823m) on the spreading-axis, Archean site (12o56.35'N, 143o37.89'E, depth: 2986m), and Pika+Urashima sites (12o55.13'N, 143o38.92'E, depth: 2773m) on the off-axis seamount, respectively. We conducted nine BMS (Benthic Multi-coring System) drillings during the Hakurei-Maru No.2 cruise of TAIGA project (see below) in June 2010. Both basalt glasses and associated seafloor massive sulfide ores from these sites are cored and served for ICP-MS analyses. Multi-element plot of basalt glass indicates that both on-axis and off-axis basalts have similar pattern and are categorized as differentiated MORB and basaltic andesite which cannot be produced by fractionation of MORB, respectively. Sulfide ores at on-axis and off-axis sites show similar mineral assemblage of pyrite/marcasite, sphalerite, chalcopyrite, barite, and limited occurrence of galena only at on-axis site. Fluid-mobile elements such as As, Ba, Pb and others in sulfide ores show systematic increase at off-axis sites which reflect the influence of subduction zone fluids towards the Mariana arc. The sulfur isotope composition of pyrite/marcasite from on-axis sites shows values (+6.4 - +7.9 permil) typically observed in arc magma-related hydrothermal deposits (Suzuki, unpubl. data). On the other hand, those observed at off-axis sites (Archean; +3.6 - +6.9 permil, Pika; +0.8 - +3.5 permil) are similar to the composition of sulfides on mid-ocean ridges where the influence of sulfur

  14. Landscape Composition and Spatial Prediction of Alveolar Echinococcosis in Southern Ningxia, China

    PubMed Central

    Pleydell, David R. J.; Yang, Yu Rong; Danson, F. Mark; Raoul, Francis; Craig, Philip S.; McManus, Donald P.; Vuitton, Dominique A.; Wang, Qian; Giraudoux, Patrick

    2008-01-01

    Background Alveolar echinococcosis (AE) presents a serious public health challenge within China. Mass screening ultrasound surveys can detect pre-symptomatic AE, but targeting areas identified from hospital records is inefficient regarding AE. Prediction of undetected or emerging hotspots would increase detection rates. Voles and lemmings of the subfamily Arvicolinae are important intermediate hosts in sylvatic transmission systems. Their populations reach high densities in productive grasslands where food and cover are abundant. Habitat availability is thought to affect arvicoline population dynamic patterns and definitive host–intermediate host interactions. Arvicoline habitat correlates with AE prevalence in Western Europe and southern Gansu Province, China. Methods and Findings Xiji County, Ningxia Hui Autonomous Region, borders southern Gansu. The aims of this study were to map AE prevalence across Xiji and test arvicoline habitat as a predictor. Land cover was mapped using remotely sensed (Landsat) imagery. Infection status of 3,205 individuals screened in 2002–2003 was related, using generalised additive mixed models, to covariates: gender; farming; ethnicity; dog ownership; water source; and areal cover of mountain pasture and lowland pasture. A Markov random field modelled additional spatial variation and uncertainty. Mountain pasture and lowland pasture were associated with below and above average AE prevalence, respectively. Conclusions Low values of the normalised difference vegetation index indicated sub-optimality of lowland pasture for grassland arvicolines. Unlike other known endemic areas, grassland arvicolines probably did not provide the principal reservoir for Echinococcus multilocularis in Xiji. This result is consistent with recent small mammal surveys reporting low arvicoline densities and high densities of hamsters, pikas and jerboas, all suitable intermediate hosts for E. multilocularis, in reforested lowland pasture. The risk of re

  15. Comparative phylogeography highlights the double-edged sword of climate change faced by arctic- and alpine-adapted mammals.

    PubMed

    Lanier, Hayley C; Gunderson, Aren M; Weksler, Marcelo; Fedorov, Vadim B; Olson, Link E

    2015-01-01

    Recent studies suggest that alpine and arctic organisms may have distinctly different phylogeographic histories from temperate or tropical taxa, with recent range contraction into interglacial refugia as opposed to post-glacial expansion out of refugia. We use a combination of phylogeographic inference, demographic reconstructions, and hierarchical Approximate Bayesian Computation to test for phylodemographic concordance among five species of alpine-adapted small mammals in eastern Beringia. These species (Collared Pikas, Hoary Marmots, Brown Lemmings, Arctic Ground Squirrels, and Singing Voles) vary in specificity to alpine and boreal-tundra habitat but share commonalities (e.g., cold tolerance and nunatak survival) that might result in concordant responses to Pleistocene glaciations. All five species contain a similar phylogeographic disjunction separating eastern and Beringian lineages, which we show to be the result of simultaneous divergence. Genetic diversity is similar within each haplogroup for each species, and there is no support for a post-Pleistocene population expansion in eastern lineages relative to those from Beringia. Bayesian skyline plots for four of the five species do not support Pleistocene population contraction. Brown Lemmings show evidence of late Quaternary demographic expansion without subsequent population decline. The Wrangell-St. Elias region of eastern Alaska appears to be an important zone of recent secondary contact for nearctic alpine mammals. Despite differences in natural history and ecology, similar phylogeographic histories are supported for all species, suggesting that these, and likely other, alpine- and arctic-adapted taxa are already experiencing population and/or range declines that are likely to synergistically accelerate in the face of rapid climate change. Climate change may therefore be acting as a double-edged sword that erodes genetic diversity within populations but promotes divergence and the generation of

  16. Comparative Phylogeography Highlights the Double-Edged Sword of Climate Change Faced by Arctic- and Alpine-Adapted Mammals

    PubMed Central

    Lanier, Hayley C.; Gunderson, Aren M.; Weksler, Marcelo; Fedorov, Vadim B.; Olson, Link E.

    2015-01-01

    Recent studies suggest that alpine and arctic organisms may have distinctly different phylogeographic histories from temperate or tropical taxa, with recent range contraction into interglacial refugia as opposed to post-glacial expansion out of refugia. We use a combination of phylogeographic inference, demographic reconstructions, and hierarchical Approximate Bayesian Computation to test for phylodemographic concordance among five species of alpine-adapted small mammals in eastern Beringia. These species (Collared Pikas, Hoary Marmots, Brown Lemmings, Arctic Ground Squirrels, and Singing Voles) vary in specificity to alpine and boreal-tundra habitat but share commonalities (e.g., cold tolerance and nunatak survival) that might result in concordant responses to Pleistocene glaciations. All five species contain a similar phylogeographic disjunction separating eastern and Beringian lineages, which we show to be the result of simultaneous divergence. Genetic diversity is similar within each haplogroup for each species, and there is no support for a post-Pleistocene population expansion in eastern lineages relative to those from Beringia. Bayesian skyline plots for four of the five species do not support Pleistocene population contraction. Brown Lemmings show evidence of late Quaternary demographic expansion without subsequent population decline. The Wrangell-St. Elias region of eastern Alaska appears to be an important zone of recent secondary contact for nearctic alpine mammals. Despite differences in natural history and ecology, similar phylogeographic histories are supported for all species, suggesting that these, and likely other, alpine- and arctic-adapted taxa are already experiencing population and/or range declines that are likely to synergistically accelerate in the face of rapid climate change. Climate change may therefore be acting as a double-edged sword that erodes genetic diversity within populations but promotes divergence and the generation of

  17. Appearance of Iron-based Microbial Ecosystems on and below the Seafloor: a Case Study of the Southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Kato, S.; Kentaro, K.; Toki, T.; Ishibashi, J.; Tsunogai, U.; Hirota, A.; Suzuki, K.; Moriya, O.; Yamagishi, A.

    2012-12-01

    Microbial community structures in deep-sea hydrothermal vents fields are constrained by available energy yields provided by inorganic redox reactions, which are in turn controlled by chemical composition of hydrothermal fluids. To date, geochemical and microbiological studies have been conducted in deep-sea hydrothermal vents at three geographically different areas (Snail, Archaean and Pika sites) of the Southern Mariana Trough (SMT). A variety of geochemical data of hydrothermal fluids and an unparalleled microbiological data of various samples (i.e., sulfide structures of active vents, iron-rich microbial mats, borehole fluids and surrounding bottom seawater) are available for comparative analyses. In the present study, we summarize these geochemical and microbiological characteristics and assess the relationship between the microbial community structures and the fluid geochemistry in the SMT by thermodynamic modeling. In the high-temperature vent fluids, aerobic sulfide-oxidation has the potential to yield large amounts of bioavailable energy in the vent fluids, which is consistent with the detection of species related to sulfide-oxidizing bacteria (such as Thiomicrospira in the Gammaproteobacteria and Sulfurimonas in the Epsilonproteobacteria). In contrast, the bioavailable energy yield from aerobic iron-oxidation reactions in the low-temperature fluids collected from man-made boreholes and several natural vents were comparable to or higher than those from sulfide-oxidation. This is consistent with the detection of species related to iron-oxidizing bacteria (Mariprofundus in the Zetaproteobacteria) in these low-temperature samples. These results provide novel insights into the presence and significance of iron-based microbial ecosystems in deep-sea hydrothermal fields.

  18. Molecular characterization of adipose tissue in the African elephant (Loxodonta africana).

    PubMed

    Nilsson, Emeli M; Fainberg, Hernan P; Choong, Siew S; Giles, Thomas C; Sells, James; May, Sean; Stansfield, Fiona J; Allen, William R; Emes, Richard D; Mostyn, Alison; Mongan, Nigel P; Yon, Lisa

    2014-01-01

    Adipose tissue (AT) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT) was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit), Lepus oiostolus (woolly hare), and members of the Ochotonidae (Pika). Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition and body

  19. Toward Improved Hyperspectral Analysis in Semiarid Systems

    NASA Astrophysics Data System (ADS)

    Glenn, N. F.; Mitchell, J.

    2012-12-01

    Idaho State University's Boise Center Aerospace Laboratory (BCAL) has processed and applied hyperspectral data for a variety of biophysical sciences in semiarid systems over the past 10 years. HyMap hyperspectral data have been used in most of these studies, along with AVIRIS, CASI, and PIKA-II data. Our studies began with the detection of individual weed species, such as leafy spurge, corroborated with extensive field analysis, including spectrometer data. Early contributions to the field of hyperspectral analysis included the use of: time-series datasets and classification threshold methods for target detection, and subpixel analysis for characterizing weed invasions and post-fire vegetation and soil conditions. Subsequent studies optimized subpixel unmixing performance using spectral subsetting and vegetation abundance investigations. More recent studies have extended the application of hyperspectral data from individual plant species detection to identification of biochemical constituents. We demonstrated field and airborne hyperspectral Nitrogen absorption in sagebrush using combinations of data reduction and spectral transformation techniques (i.e., continuum removal, derivative analysis, partial least squares regression). In spite of these and many other successful demonstrations, gaps still exist in effective species level discrimination due to the high complexity of soil and nonlinear mixing in semiarid shrubland. BCAL studies are currently focusing on complimenting narrowband vegetation indices with LiDAR (light detection and ranging, both airborne and ground-based) derivatives to improve vegetation cover predictions. Future combinations of LiDAR and hyperspectral data will involve exploring the full range spectral information and serve as an integral step in scaling shrub biomass estimates from plot to landscape and regional scales.

  20. Low, complex and probably reticulated chromosome evolution of Sciuromorpha (Rodentia) and Lagomorpha.

    PubMed

    Richard, F; Dutrillaux, B

    2012-01-01

    Lagomorpha (rabbits and pikas) and Sciuromorpha (squirrels) are grouped in the Glires superorder. Their chromosome diversification, since their separation from the eutherian mammalian common ancestor, was characterized by a low rate of chromosome rearrangements. Consequently, the structure of some chromosomes was either conserved or only slightly modified, making their comparison easy at the genus, family and even order level. Interspecific in situ hybridization (Zoo-FISH) largely corroborates classical cytogenetic data but provides much more reliability in comparisons, especially for distant species. We reconstructed common ancestral karyotypes for Glires, Lagomorpha, Sciuromorpha, and Sciuridae species, and then, determined the chromosome changes separating these ancestors from their common eutherian ancestor. We propose that reticulated evolution occurred during the diversification of Glires, which implies that several pericentric inversions and Robertsonian translocations were conserved in the heterozygous status for an extensive period. Finally, among Lagomorpha and Sciuromorpha, we focused on Leporidae and Sciuridae chromosome evolution. In the various attempts to establish dichotomic evolutionary schemes, it was necessary to admit that multiple homoplasies (convergent and reverse rearrangements) occurred in Sciuridae and in a lesser degree, in Leporidae. In Leporidae, additional rearrangements were sufficient to propose a resolved phylogeny. However, a resolved phylogeny was not possible for Sciuridae because most of the rearrangements occurred in terminal branches. We conclude that a reticulated evolution took place early during the evolution of both families and lasted longer in Sciuridae than in Leporidae. In Sciuridae, most chromosome rearrangements were pericentric inversions involving short fragments. Such rearrangements have only mild meiotic consequences, which may explain the long persistence of the heterozygous status characterizing reticulated

  1. Faster Speciation and Reduced Extinction in the Tropics Contribute to the Mammalian Latitudinal Diversity Gradient

    PubMed Central

    Rolland, Jonathan; Condamine, Fabien L.; Jiguet, Frederic; Morlon, Hélène

    2014-01-01

    The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals) peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas) reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha), high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha), or both (Chiroptera and Rodentia). Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the “out of the tropics” hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern. PMID:24492316

  2. Faster speciation and reduced extinction in the tropics contribute to the Mammalian latitudinal diversity gradient.

    PubMed

    Rolland, Jonathan; Condamine, Fabien L; Jiguet, Frederic; Morlon, Hélène

    2014-01-01

    The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals) peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas) reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha), high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha), or both (Chiroptera and Rodentia). Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the "out of the tropics" hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern.

  3. Evolutionary history of lagomorphs in response to global environmental change.

    PubMed

    Ge, Deyan; Wen, Zhixin; Xia, Lin; Zhang, Zhaoqun; Erbajeva, Margarita; Huang, Chengming; Yang, Qisen

    2013-01-01

    Although species within Lagomorpha are derived from a common ancestor, the distribution range and body size of its two extant groups, ochotonids and leporids, are quite differentiated. It is unclear what has driven their disparate evolutionary history. In this study, we compile and update all fossil records of Lagomorpha for the first time, to trace the evolutionary processes and infer their evolutionary history using mitochondrial genes, body length and distribution of extant species. We also compare the forage selection of extant species, which offers an insight into their future prospects. The earliest lagomorphs originated in Asia and later diversified in different continents. Within ochotonids, more than 20 genera occupied the period from the early Miocene to middle Miocene, whereas most of them became extinct during the transition from the Miocene to Pliocene. The peak diversity of the leporids occurred during the Miocene to Pliocene transition, while their diversity dramatically decreased in the late Quaternary. Mantel tests identified a positive correlation between body length and phylogenetic distance of lagomorphs. The body length of extant ochotonids shows a normal distribution, while the body length of extant leporids displays a non-normal pattern. We also find that the forage selection of extant pikas features a strong preference for C(3) plants, while for the diet of leporids, more than 16% of plant species are identified as C(4) (31% species are from Poaceae). The ability of several leporid species to consume C(4) plants is likely to result in their size increase and range expansion, most notably in Lepus. Expansion of C(4) plants in the late Miocene, the so-called 'nature's green revolution', induced by global environmental change, is suggested to be one of the major 'ecological opportunities', which probably drove large-scale extinction and range contraction of ochotonids, but inversely promoted diversification and range expansion of leporids.

  4. Molecular Characterization of Adipose Tissue in the African Elephant (Loxodonta africana)

    PubMed Central

    Choong, Siew S.; Giles, Thomas C.; Sells, James; May, Sean; Stansfield, Fiona J.; Allen, William R.; Emes, Richard D.; Mostyn, Alison; Mongan, Nigel P.; Yon, Lisa

    2014-01-01

    Adipose tissue (AT) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT) was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit), Lepus oiostolus (woolly hare), and members of the Ochotonidae (Pika). Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition and body

  5. Evolutionary History of Lagomorphs in Response to Global Environmental Change

    PubMed Central

    Ge, Deyan; Wen, Zhixin; Xia, Lin; Zhang, Zhaoqun; Erbajeva, Margarita; Huang, Chengming; Yang, Qisen

    2013-01-01

    Although species within Lagomorpha are derived from a common ancestor, the distribution range and body size of its two extant groups, ochotonids and leporids, are quite differentiated. It is unclear what has driven their disparate evolutionary history. In this study, we compile and update all fossil records of Lagomorpha for the first time, to trace the evolutionary processes and infer their evolutionary history using mitochondrial genes, body length and distribution of extant species. We also compare the forage selection of extant species, which offers an insight into their future prospects. The earliest lagomorphs originated in Asia and later diversified in different continents. Within ochotonids, more than 20 genera occupied the period from the early Miocene to middle Miocene, whereas most of them became extinct during the transition from the Miocene to Pliocene. The peak diversity of the leporids occurred during the Miocene to Pliocene transition, while their diversity dramatically decreased in the late Quaternary. Mantel tests identified a positive correlation between body length and phylogenetic distance of lagomorphs. The body length of extant ochotonids shows a normal distribution, while the body length of extant leporids displays a non-normal pattern. We also find that the forage selection of extant pikas features a strong preference for C3 plants, while for the diet of leporids, more than 16% of plant species are identified as C4 (31% species are from Poaceae). The ability of several leporid species to consume C4 plants is likely to result in their size increase and range expansion, most notably in Lepus. Expansion of C4 plants in the late Miocene, the so-called ‘nature’s green revolution’, induced by global environmental change, is suggested to be one of the major ‘ecological opportunities’, which probably drove large-scale extinction and range contraction of ochotonids, but inversely promoted diversification and range expansion of leporids

  6. Diversities in hepatic HIF-1, IGF-I/IGFBP-1, LDH/ICD, and their mRNA expressions induced by CoCl(2) in Qinghai-Tibetan plateau mammals and sea level mice.

    PubMed

    Chen, Xue-Qun; Wang, Shi-Jun; Du, Ji-Zeng; Chen, Xiao-Cheng

    2007-01-01

    Ochotona curzoniae and Microtus oeconomus are the native mammals living on the Qinghai-Tibetan-Plateau of China. The molecular mechanisms of their acclimatization to the Plateau-hypoxia remain unclear. Expressions of hepatic hypoxia-inducible factor (HIF)-1alpha, insulin-like growth factor-I (IGF-I)/IGF binding protein (BP)-1(IGFBP-1; including genes), and key metabolic enzymatic genes [lactate dehydrogenase (LDH)-A/isocitrate dehydrogenase (ICD)] are compared in Qinghai-Tibetan-Plateau mammals and sea-level mice after injection of CoCl(2) (20, 40, or 60 mg/kg) and normobaric hypoxia (16.0% O(2), 10.8% O(2), and 8.0% O(2)) for 6 h, tested by histochemistry, Western blot analysis, ELISA, and RT-PCR. Major results are CoCl(2) markedly increased 1) HIF-1alpha only in mice, 2) hepatic and circulatory IGF-I in M. oeconomus, 3) hepatic IGFBP-1 in mice and O. curzoniae, and 4) LDH-A but reduced ICD mRNA in mice (CoCl(2) 20 mg/kg) but were unchanged in the Tibetan mammals. Normobaric hypoxia markedly 1) increased HIF-1alpha and LDH-A mRNA in mice and M. oeconomus (8.0% O(2)) not in O. curzoniae, and 2) reduced ICD mRNA in mice and M. oeconomus (8.0% O(2)) not in O. curzoniae. Results suggest that 1) HIF-1alpha responsiveness to hypoxia is distinct in lowland mice and plateau mammals, reflecting a diverse tolerance of the three species to hypoxia; 2) CoCl(2) induces diversities in HIF-1, IGF-I/IGFBP-1 protein or genes in mice, M. oeconomus, and O. curzoniae. In contrast, HIF-1 mediates IGFBP-1 transcription only in mice and in M. oeconomus (subjected to severe hypoxia); 3) differences in IGF-I/IGFBP-1 expressions induced by CoCl(2) reflect significant diversities in hormone regulation and cell protection from damage; and 4) activation of anaerobic glycolysis and reduction of Krebs cycle represents strategies of lowland-animals vs. the stable metabolic homeostasis of plateau-acclimatized mammals.

  7. The ecology of tick-transmitted infections in the redwood chipmunk (Tamias ochrogenys)

    PubMed Central

    Foley, Janet E.; Nieto, Nathan C.

    2011-01-01

    The redwood chipmunk contributes to the maintenance of tick-borne diseases in northern California. The range of redwood chipmunks overlaps that of western black-legged ticks and tick-borne disease, including granulocytic anaplasmosis and Lyme borreliosis. Chipmunks have high Anaplasma phagocytophilum PCR- and seroprevalence, are infested with a diversity of Ixodes spp. ticks, and are reservoir competent for Borrelia burgdorferi. We hypothesized that chipmunks could maintain tick-borne disease on the forest floor while also potentially bridging infection to arboreal sciurids as well. We used radio-telemetry to evaluate chipmunk movement and use of trees, characterized burrows, described prevalence of tick-borne disease, and identified ticks on these chipmunks. A total of 192 chipmunks from Hendy Woods, Mendocino County, California, USA, was evaluated between November 2005 and April 2009. The mean density was 2.26–5.8 chipmunks/ha. The longest detected life span was 3 years. Female weights ranged from 80–120 g and males from 80–180 g. The A. phagocytophilum and Borrelia spp. seroprevalence was 21.4% and 24.7%, respectively, and PCR prevalence for these pathogens was 10.6% and 0%, respectively. Ixodes spp. ticks included I. angustus, I. ochotonae, I. pacificus, and I. spinipalpis. The mean infestation level was 0.92 ticks/chipmunk. Based on telemetry of 11 chipmunks, the greatest distance traveled ranged from 0.14–0.63 km for females and 0.1–1.26 km for males. Areas occupied by chipmunks ranged from 0.005–0.24 km2 for females and 0.006–0.73 km2 for males. On 3 occasions, chipmunks were found in trees. Burrows were identified under a moss-covered redwood log, deep under a live redwood tree, under a Douglas fir log, in a clump of huckleberry, in a root collection from an overturned Douglas fir tree, and in a cluster of exposed huckleberry roots. The biology of the redwood chipmunk has multiple features that allow it to be an important reservoir host for

  8. Temperature-Sensitive Mutants in the Influenza A Virus RNA Polymerase: Alterations in the PA Linker Reduce Nuclear Targeting of the PB1-PA Dimer and Result in Viral Attenuation

    PubMed Central

    Da Costa, Bruno; Sausset, Alix; Munier, Sandie; Ghounaris, Alexandre; Naffakh, Nadia; Le Goffic, Ronan

    2015-01-01

    ABSTRACT The influenza virus RNA-dependent RNA polymerase catalyzes genome replication and transcription within the cell nucleus. Efficient nuclear import and assembly of the polymerase subunits PB1, PB2, and PA are critical steps in the virus life cycle. We investigated the structure and function of the PA linker (residues 197 to 256), located between its N-terminal endonuclease domain and its C-terminal structured domain that binds PB1, the polymerase core. Circular dichroism experiments revealed that the PA linker by itself is structurally disordered. A large series of PA linker mutants exhibited a temperature-sensitive (ts) phenotype (reduced viral growth at 39.5°C versus 37°C/33°C), suggesting an alteration of folding kinetic parameters. The ts phenotype was associated with a reduced efficiency of replication/transcription of a pseudoviral reporter RNA in a minireplicon assay. Using a fluorescent-tagged PB1, we observed that ts and lethal PA mutants did not efficiently recruit PB1 to reach the nucleus at 39.5°C. A protein complementation assay using PA mutants, PB1, and β-importin IPO5 tagged with fragments of the Gaussia princeps luciferase showed that increasing the temperature negatively modulated the PA-PB1 and the PA-PB1-IPO5 interactions or complex stability. The selection of revertant viruses allowed the identification of different types of compensatory mutations located in one or the other of the three polymerase subunits. Two ts mutants were shown to be attenuated and able to induce antibodies in mice. Taken together, our results identify a PA domain critical for PB1-PA nuclear import and that is a “hot spot” to engineer ts mutants that could be used to design novel attenuated vaccines. IMPORTANCE By targeting a discrete domain of the PA polymerase subunit of influenza virus, we were able to identify a series of 9 amino acid positions that are appropriate to engineer temperature-sensitive (ts) mutants. This is the first time that a large

  9. Development of a lentivirus vector-based assay for non-destructive monitoring of cell fusion activity.

    PubMed

    Neshati, Zeinab; Liu, Jia; Zhou, Guangqian; Schalij, Martin J; de Vries, Antoine A F

    2014-01-01

    Cell-to-cell fusion can be quantified by endowing acceptor and donor cells with latent reporter genes/proteins and activators of these genes/proteins, respectively. One way to accomplish this goal is by using a bipartite lentivirus vector (LV)-based cell fusion assay system in which the cellular fusion partners are transduced with a flippase-activatable Photinus pyralis luciferase (PpLuc) expression unit (acceptor cells) or with a recombinant gene encoding FLPeNLS+, a nuclear-targeted and molecularly evolved version of flippase (donor cells). Fusion of both cell populations will lead to the FLPe-dependent generation of a functional PpLuc gene. PpLuc activity is typically measured in cell lysates, precluding consecutive analysis of one cell culture. Therefore, in this study the PpLuc-coding sequence was replaced by that of Gaussia princeps luciferase (GpLuc), a secretory protein allowing repeated analysis of the same cell culture. In myotubes the spread of FLPeNLS+ may be limited due to its nuclear localization signal (NLS) causing low signal outputs. To test this hypothesis, myoblasts were transduced with LVs encoding either FLPeNLS+ or an NLS-less version of FLPe (FLPeNLS-) and subsequently co-cultured in different ratios with myoblasts containing the FLPe-activatable GpLuc expression cassette. At different times after induction of cell-to-cell fusion the GpLuc activity in the culture medium was determined. FLPeNLS+ and FLPeNLS- both activated the latent GpLuc gene but when the percentage of FLPe-expressing myoblasts was limiting, FLPeNLS+ generally yielded slightly higher signals than FLPeNLS- while at low acceptor-to-donor cell ratios FLPeNLS- was usually superior. The ability of FLPeNLS+ to spread through myofibers and to induce reporter gene expression is thus not limited by its NLS. However, at high FLPe concentrations the presence of the NLS negatively affected reporter gene expression. In summary, a rapid and simple chemiluminescence assay for quantifying

  10. Development of a Lentivirus Vector-Based Assay for Non-Destructive Monitoring of Cell Fusion Activity

    PubMed Central

    Neshati, Zeinab; Liu, Jia; Zhou, Guangqian; Schalij, Martin J.; de Vries, Antoine A. F.

    2014-01-01

    Cell-to-cell fusion can be quantified by endowing acceptor and donor cells with latent reporter genes/proteins and activators of these genes/proteins, respectively. One way to accomplish this goal is by using a bipartite lentivirus vector (LV)-based cell fusion assay system in which the cellular fusion partners are transduced with a flippase-activatable Photinus pyralis luciferase (PpLuc) expression unit (acceptor cells) or with a recombinant gene encoding FLPeNLS+, a nuclear-targeted and molecularly evolved version of flippase (donor cells). Fusion of both cell populations will lead to the FLPe-dependent generation of a functional PpLuc gene. PpLuc activity is typically measured in cell lysates, precluding consecutive analysis of one cell culture. Therefore, in this study the PpLuc-coding sequence was replaced by that of Gaussia princeps luciferase (GpLuc), a secretory protein allowing repeated analysis of the same cell culture. In myotubes the spread of FLPeNLS+ may be limited due to its nuclear localization signal (NLS) causing low signal outputs. To test this hypothesis, myoblasts were transduced with LVs encoding either FLPeNLS+ or an NLS-less version of FLPe (FLPeNLS−) and subsequently co-cultured in different ratios with myoblasts containing the FLPe-activatable GpLuc expression cassette. At different times after induction of cell-to-cell fusion the GpLuc activity in the culture medium was determined. FLPeNLS+ and FLPeNLS− both activated the latent GpLuc gene but when the percentage of FLPe-expressing myoblasts was limiting, FLPeNLS+ generally yielded slightly higher signals than FLPeNLS− while at low acceptor-to-donor cell ratios FLPeNLS− was usually superior. The ability of FLPeNLS+ to spread through myofibers and to induce reporter gene expression is thus not limited by its NLS. However, at high FLPe concentrations the presence of the NLS negatively affected reporter gene expression. In summary, a rapid and simple chemiluminescence assay for

  11. Goat meat does not cause increased blood pressure.

    PubMed

    Sunagawa, Katsunori; Kishi, Tetsuya; Nagai, Ayako; Matsumura, Yuka; Nagamine, Itsuki; Uechi, Shuntoku

    2014-01-01

    While there are persistent rumors that the consumption of goat meat dishes increases blood pressure, there is no scientific evidence to support this. Two experiments were conducted to clarify whether or not blood pressure increases in conjunction with the consumption of goat meat dishes. In experiment 1, 24 Dahl/Iwai rats (15 weeks old, body weight 309.3±11.1 g) were evenly separated into 4 groups. The control group (CP) was fed a diet containing 20% chicken and 0.3% salt on a dry matter basis. The goat meat group (GM) was fed a diet containing 20% goat meat and 0.3% salt. The goat meat/salt group (GS) was fed a diet containing 20% goat meant and 3% to 4% salt. The Okinawan mugwort (Artemisia Princeps Pampan)/salt group (GY) was fed a diet containing 20% goat meat, 3% to 4% salt and 5% of freeze-dried mugwort powder. The experiment 1 ran for a period of 14 weeks during which time the blood pressure of the animals was recorded. The GS, and GY groups consumed significantly more water (p<0.01) than the CP and GM groups despite the fact that their diet consumption levels were similar. The body weight of animals in the CP, GM, and GS groups was similar while the animals in the GY group were significantly smaller (p<0.01). The blood pressure in the GM group was virtually the same as the CP group throughout the course of the experiment. In contrast, while the blood pressure of the animals in the GS and GY group from 15 to 19 weeks old was the same as the CP group, their blood pressures were significantly higher (p<0.01) after 20 weeks of age. The GY group tended to have lower blood pressure than the GS group. In experiment 2, in order to clarify whether or not the increase in blood pressure in the GS group and the GY group in experiment 1 was caused by an excessive intake of salt, the effects on blood pressure of a reduction of salt in diet were investigated. When amount of salt in the diet of the GS and GY group was reduced from 4% to 0.3%, the animal's blood pressure

  12. Goat Meat Does Not Cause Increased Blood Pressure

    PubMed Central

    Sunagawa, Katsunori; Kishi, Tetsuya; Nagai, Ayako; Matsumura, Yuka; Nagamine, Itsuki; Uechi, Shuntoku

    2014-01-01

    While there are persistent rumors that the consumption of goat meat dishes increases blood pressure, there is no scientific evidence to support this. Two experiments were conducted to clarify whether or not blood pressure increases in conjunction with the consumption of goat meat dishes. In experiment 1, 24 Dahl/Iwai rats (15 weeks old, body weight 309.3±11.1 g) were evenly separated into 4 groups. The control group (CP) was fed a diet containing 20% chicken and 0.3% salt on a dry matter basis. The goat meat group (GM) was fed a diet containing 20% goat meat and 0.3% salt. The goat meat/salt group (GS) was fed a diet containing 20% goat meant and 3% to 4% salt. The Okinawan mugwort (Artemisia Princeps Pampan)/salt group (GY) was fed a diet containing 20% goat meat, 3% to 4% salt and 5% of freeze-dried mugwort powder. The experiment 1 ran for a period of 14 weeks during which time the blood pressure of the animals was recorded. The GS, and GY groups consumed significantly more water (p<0.01) than the CP and GM groups despite the fact that their diet consumption levels were similar. The body weight of animals in the CP, GM, and GS groups was similar while the animals in the GY group were significantly smaller (p<0.01). The blood pressure in the GM group was virtually the same as the CP group throughout the course of the experiment. In contrast, while the blood pressure of the animals in the GS and GY group from 15 to 19 weeks old was the same as the CP group, their blood pressures were significantly higher (p<0.01) after 20 weeks of age. The GY group tended to have lower blood pressure than the GS group. In experiment 2, in order to clarify whether or not the increase in blood pressure in the GS group and the GY group in experiment 1 was caused by an excessive intake of salt, the effects on blood pressure of a reduction of salt in diet were investigated. When amount of salt in the diet of the GS and GY group was reduced from 4% to 0.3%, the animal’s blood pressure

  13. [Typus melancholicus and melancholia: Theoretical synthesis using a clinical case].

    PubMed

    Englebert, J; Stanghellini, G

    2016-02-01

    construction and refinement of theoretical and conceptual frameworks (like princeps Tellenbach's studies). Over-synchronized tempo and over-identification with social role are emblematically in this case the two sides of the same coin. A parallelism can be established between synchronization (with the mother) and respect for the role at the expense of own identity. The clinical case of Jonas highlights a conceptual bridge between the model of melancholia as loss of social role and the model of melancholia as desynchronization. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  14. [Modified Exeter technique in revision hip surgery].

    PubMed

    de Thomasson, E; Guingand, O; Terracher, R; Mazel, C

    2008-06-01

    in two (Postel-Merle-d'Aubigné score). Defective distal cementing with implant migration (less than 5 mm) was noted in four cases followed by secondary stabilization. Transformation of the allograft occurred in 36 cases, associated with corticalization of the recipient bone in 14. This technique is reproducible since primary stability was obtained in 90% of hips, without hindering transformation of the allograft. The results, which are sustained over time, are the same as with the princeps technique and no radiographic evidence of stress shielding could be found.

  15. Does exposure to noise from human activities compromise sensory information from cephalopod statocysts?

    NASA Astrophysics Data System (ADS)

    Solé, Marta; Lenoir, Marc; Durfort, Mercè; López-Bejar, Manel; Lombarte, Antoni; van der Schaar, Mike; André, Michel

    2013-10-01

    Many anthropogenic noise sources are nowadays contributing to the general noise budget of the oceans. The extent to which sound in the sea impacts and affects marine life is a topic of considerable current interest both to the scientific community and to the general public. Cepaholopods potentially represent a group of species whose ecology may be influenced by artificial noise that would have a direct consequence on the functionality and sensitivity of their sensory organs, the statocysts. These are responsible for their equilibrium and movements in the water column. Controlled Exposure Experiments, including the use of a 50-400Hz sweep (RL=157±5dB re 1μPa with peak levels up to SPL=175dB re 1μPa) revealed lesions in the statocysts of four cephalopod species of the Mediterranean Sea, when exposed to low frequency sounds: (n=76) of Sepia officinalis, (n=4) Octopus vulgaris, (n=5) Loligo vulgaris and (n=2) Illex condietii. The analysis was performed through scanning (SEM) and transmission (TEM) electron microscopical techniques of the whole inner structure of the cephalopods' statocyst, especially on the macula and crista. All exposed individuals presented the same lesions and the same incremental effects over time, consistent with a massive acoustic trauma observed in other species that have been exposed to much higher intensities of sound: Immediately after exposure, the damage was observed in the macula statica princeps (msp) and in the crista sensory epithelium. Kinocilia on hair cells were either missing or were bent or flaccid. A number of hair cells showed protruding apical poles and ruptured lateral plasma membranes, most probably resulting from the extrusion of cytoplasmic material. Hair cells were also partially ejected from the sensory epithelium, and spherical holes corresponding to missing hair cells were visible in the epithelium. The cytoplasmic content of the damaged hair cells showed obvious changes, including the presence of numerous vacuoles

  16. Mapping the interactome of HPV E6 and E7 oncoproteins with the ubiquitin-proteasome system.

    PubMed

    Poirson, Juline; Biquand, Elise; Straub, Marie-Laure; Cassonnet, Patricia; Nominé, Yves; Jones, Louis; van der Werf, Sylvie; Travé, Gilles; Zanier, Katia; Jacob, Yves; Demeret, Caroline; Masson, Murielle

    2017-08-08

    Protein ubiquitination and its reverse reaction, deubiquitination, regulate protein stability, protein binding activity, and their subcellular localization. These reactions are catalyzed by the enzymes E1, E2, and E3 ubiquitin (Ub) ligases and deubiquitinases (DUBs). The Ub-proteasome system (UPS) is targeted by viruses for the sake of their replication and to escape host immune response. To identify novel partners of human papillomavirus 16 (HPV16) E6 and E7 proteins, we assembled and screened a library of 590 cDNAs related to the UPS by using the Gaussia princeps luciferase protein complementation assay. HPV16 E6 was found to bind to the homology to E6AP C terminus-type Ub ligase (E6AP), three really interesting new gene (RING)-type Ub ligases (MGRN1, LNX3, LNX4), and the DUB Ub-specific protease 15 (USP15). Except for E6AP, the binding of UPS factors did not require the LxxLL-binding pocket of HPV16 E6. LNX3 bound preferentially to all high-risk mucosal HPV E6 tested, whereas LNX4 bound specifically to HPV16 E6. HPV16 E7 was found to bind to several broad-complex tramtrack and bric-a-brac domain-containing proteins (such as TNFAIP1/KCTD13) that are potential substrate adaptors of Cullin 3-RING Ub ligases, to RING-type Ub ligases implicated in innate immunity (RNF135, TRIM32, TRAF2, TRAF5), to the substrate adaptor DCAF15 of Cullin 4-RING Ub ligase and to some DUBs (USP29, USP33). The binding to UPS factors did not require the LxCxE motif but rather the C-terminal region of HPV16 E7 protein. The identified UPS factors interacted with most of E7 proteins across different HPV types. This study establishes a strategy for the rapid identification of interactions between host or pathogen proteins and the human ubiquitination system. © 2017 Federation of European Biochemical Societies.

  17. Drug-Encoded Biomarkers for Monitoring Biological Therapies

    PubMed Central

    Bedenk, Kristina; Zhang, Qian; Frentzen, Alexa; Cappello, Joseph; Fischer, Utz; Szalay, Aladar A.

    2015-01-01

    Blood tests are necessary, easy-to-perform and low-cost alternatives for monitoring of oncolytic virotherapy and other biological therapies in translational research. Here we assessed three candidate proteins with the potential to be used as biomarkers in biological fluids: two glucuronidases from E. coli (GusA) and Staphylococcus sp. RLH1 (GusPlus), and the luciferase from Gaussia princeps (GLuc). The three genes encoding these proteins were inserted individually into vaccinia virus GLV-1h68 genome under the control of an identical promoter. The three resulting recombinant viruses were used to infect tumor cells in cultures and human tumor xenografts in nude mice. In contrast to the actively secreted GLuc, the cytoplasmic glucuronidases GusA and GusPlus were released into the supernatants only as a result of virus-mediated oncolysis. GusPlus resulted in the most sensitive detection of enzyme activity under controlled assay conditions in samples containing as little as 1 pg/ml of GusPlus, followed by GusA (25 pg/ml) and GLuc (≥375 pg/ml). Unexpectedly, even though GusA had a lower specific activity compared to GusPlus, the substrate conversion in the serum of tumor-bearing mice injected with the GusA-encoding virus strains was substantially higher than that of GusPlus. This was attributed to a 3.2 fold and 16.2 fold longer half-life of GusA in the blood stream compared to GusPlus and GLuc respectively, thus a more sensitive monitor of virus replication than the other two enzymes. Due to the good correlation between enzymatic activity of expressed marker gene and virus titer, we conclude that the amount of the biomarker protein in the body fluid semiquantitatively represents the amount of virus in the infected tumors which was confirmed by low light imaging. We found GusA to be the most reliable biomarker for monitoring oncolytic virotherapy among the three tested markers. PMID:26348361

  18. Pasture degradation modifies soil organic matter properties and biochemical functioning in Tibetan grasslands

    NASA Astrophysics Data System (ADS)

    Spielvogel, Sandra; Steingräber, Laura; Schleuß, Per; Kuzyakov, Yakov; Guggenberger, Georg

    2015-04-01

    Kobresia pastures of the Tibetan Plateau represent the world's largest alpine ecosystem. Moderate husbandry on Kobresia pastures is beneficial for the storage of soil organic carbon (OC), nitrogen (N) and other nutrients and prevents erosion by establishment of sedge-turf root mats with high OC allocation rates below ground. However, undisturbed root mats are affected by freezing and thawing processes, which cause initial ice cracks. As a consequence decomposition of root mat layers will be accelerated and current sedentarization programs with concomitant increased grazing intensity may additionally enhance root mat degradation. Finally, cracks are enlarged by water and wind erosion as well as pika activities until bare soil surface areas without root mat horizons occur. The aim of this study was to understand the impact of the root mat layer on soil organic carbon stabilization and microbial functioning depending on soil depths and to predict future changes (OC, N and nutrient losses, soil microbial functioning in SOM transformation) by overgrazing and climate change. We investigated the mineral soil below Kobresia root mats along a false time degradation sequence ranging from stage 1 (intact root mat) to stage 4 (mats with large cracks and bare soil patches). Vertical gradients of δ13C values, neutral sugar, cutin and suberin contents as well as microbial biomass estimated by total phospholipid fatty acid (PLFA), microbial community composition (PLFA profiles) and activities of six extracellular enzymes involved in the C, N, and P cycle were assessed. Soil OC and N contents as well as C/N ratios indicate an increasing illuviation of topsoil material into the subsoil with advancing root mat degradation. This was confirmed by more negative δ13C values as well as significantly (p ≤ 0.05) increasing contributions of cutin derived hydroxy fatty acids to OC in the subsoils from degradation stages 1 to 4. PLFA profiles were surprisingly similar in the subsoils of

  19. Geochemistry of Hydrothermal Fluids in South Mariana Backarc Spreading Center

    NASA Astrophysics Data System (ADS)

    Ishibashi, J.; Yamanaka, T.; Kimura, H.; Hirota, A.; Toki, T.; Tsunogai, U.; Gamo, T.; Utsumi, M.; Roe, K.; Miyabe, S.; Okamura, K.

    2004-12-01

    Fluid samples were collected from active hydrothermal sites along the south Mariana backarc spreading center, during dive programs with SHINKAI6500 (JAMSTEC) / Yokosuka (YK03-09 cruise) in Oct. 2003, and with ROPOS (CSSF) / Thomas G. Thompson (TN167A cruise) in March 2004. Fluid geochemistry shows diversity among three sites, probably reflecting their geological settings. High temperature fluid (T=315° C) from black smokers at the top of an off-axis seamount (Pika site: 12° 55.1'N, 143° 38.9'E, depth=2830m) shows metal-rich signature and high Cl concentration (=600mM). Modest high temperature fluid (T=213° C) from giant sulfide structure of a few ten meters high (Archaean Site: 12° 56.3'N, 143° 38.0'E, depth=2990m) shows slight K-rich from ridge-type fluids and low Cl concentration (=470mM). On the other hand, along the spreading axis, only shimmering venting directly from basaltic seafloor was observed (Fryer site: 12° 57.2'N, 143° 37.2'E, depth=2880m). Although temperature of the venting fluid were reported as 240° C when this site was discovered at May 2003, it has decreased to 110° C at Oct. 2003, and to 70° C at March 2004. Based on fluid chemistry composition, the shimmering fluid is considered as formed by mixing between hydrothermal fluid endmember (Mg=0) with seawater, and hydrothermal contribution has diminished for this one year. We also successfully collected fluid samples venting from the casing pipes which had been drilled by BMS at January 2004. The fluid (T=30° C) from APM01 located in the vicinity of Fryer site showed chemistry well explained by mixing of the same hydrothermal fluid endmember with seawater. Under the framework of Achaean Park Project, samples for microbiological studies were collected simultaneously, and these geochemical data provides basic information for them.

  20. Characterization of Dissolved Organic Matter from Deep-sea Floor Hydrothermal Vents in South Mariana Backarc Spreading Center

    NASA Astrophysics Data System (ADS)

    Kitajima, F.; Yamanaka, T.

    2004-12-01

    In South Mariana Backarc Spreading Center, a few active hydrothermal fields are located. We investigated a characterization of dissolved organic matter (DOM) from hydrothermal vents in this area, in order to clarify the biosphere beneath deep-sea floor. Hot water sample was collected from a drilled hole (APM01 located in Fryer site, 12o 55.22fN, 143o 37.16fE, depth 2850m) during the ROPOS/TN167A cruise in March 2004. The hole had been drilled during Hakurei-Maru 2 cruise in January 2004. Another hot water sample was collected from a natural black smoker located in Pika site (12o 55.15fN, 143o 36.96fE, depth 2773m) during YK03-09 cruise. In this investigation, we developed a standalone filtration system in order to collect and enrich dissolved organic matter of quite low concentration. This system was designed to be put near hydrothermal vents for at least 24h. This system has an ODS disk (EmporeTM High Performance Extraction Disk C18 90mmφ) with a pre-filter (Whatman GMF 1 μ)m filter paper) to adsorb dilute organics. We collected DOM from the APM01 casing pipe for about 30h (Tmax = 25-30 o C, the estimated volume of filtrated water is max. 300L) using this filtration system. Adsorbed organics were eluted with methanol for 12h twice and toluene once using soxhlet extractor. Recovered amounts of methanol eluents are 72.8mg for APM01, and 89.7mg for the black smoker. Prior to GCMS analysis, we carried out high resolution 1 H-NMR measurement (400MHz), together with the DOM samples collected from the Suiyo Seamount in July-August 2001 and August 2002. Most of the samples show signals in the region of 3-4 ppm, and the samples from the vents of relatively low temperatures (APM01 and AP04: the natural vent at the Suiyo Seamount, temperature 8-48o C ) show signals also in the region of 0.8-1.6 ppm.

  1. Biodiversity and biogeography of hydrothermal vent species in the western Pacific: a biological perspective of TAIGA project

    NASA Astrophysics Data System (ADS)

    Seo, M.; Watanabe, H.; Nakamura, M.; Sasaki, T.; Ogura, T.; Yahagi, T.; Takahashi, Y.; Ishibashi, J.; Kojima, S.

    2012-12-01

    Deep-sea hydrothermal vents are scientifically interesting environments where strong interactions of geology, chemistry, and biology can be observed. The hydrothermal vents are geologically controlled in association with magmatic activities while diversity of chemicals (such as hydrogen sulfide) contained in hydrothermal fluid is controlled by geochemical interaction between heated seawater and surrounding rocks. In addition to those geological and chemical characters of hydrothermal vents, high biomasses of chemosynthetic community have been known around many vents since the first discovery in the 1970s. To understand the unique system and diversity of biological communities associated with vents is highly valuable in geological, chemical, and biological sciences. As an activity of the research project "TAIGA (Trans-crustal Advection & In-situ bio-geochemical processes of Global sub-seafloor Aquifer)" (Representative: Tetsuro Urabe, Department of Earth & Planetary Science, the University of Tokyo), we analyzed population structures and connectivity as well as larval ecology of various hydrothermal vent species in the Okinawa Trough and the Mariana Trough in an attempt to estimate faunal transitional history associated with hydrothermal activities. The specimens analyzed in the present study were collected by R/V Yokosuka with manned submersible Shinkai6500 and R/V Natsushima with ROV Hyper-Dolphin during YK10-11 and NT11-20 cruises, respectively. In the Mariana Trough (YK10-11), benthic and planktonic faunas were investigated by multiple sampling and use of plankton samplers in three hydrothermal vents (Snail, Archaean, and Urashima-Pika fields). Faunal compositions were then compared as well as size compositions and genetic diversities of major vent species among local populations. In the Okinawa Trough (NT11-20), multiple quantitative sampling was made with simultaneous environmental measurements at more than two sites in five hydrothermal vents (Minami

  2. Larval abundance and dispersal at deep-sea hydrothermal vents in the southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Beaulieu, S. E.; Watanabe, H.; Mills, S. W.; Pradillon, F.; Kojima, S.; Mullineaux, L. S.

    2010-12-01

    Since the discovery of deep-sea hydrothermal vents over thirty years ago, scientists have been perplexed by the question: “How are the faunal populations established and maintained at these very discrete and often ephemeral habitats?” For the animals that are sessile or have limited mobility as adults, dispersal to these habitats occurs early in the life cycle, as planktonic larvae in the water column. Due to the difficulties in sampling deep-sea larvae, including low abundances (dilute concentrations), we have very few quantitative estimates of larval dispersal between or larval supply to hydrothermal vents. Here, we will present results of an international, collaborative effort to study larval abundance and dispersal at vents near the back-arc spreading center in the southern Mariana Trough. On R/V Yokosuka cruise YK10-11 in September 2010, we will deploy large-volume plankton pumps at approximately 3000-m depth at Snail (also called South Backarc), Archaean, and Pika, three of the Vents (Volcanic) Unit sites in the U.S. Marianas Trench Marine National Monument. These vents are being studied as part of the Japanese multi-disciplinary program TAIGA (Trans-crustal Advection and In-situ biogeochemical proceses of Global sub-sea floor Aquifer). These will be the first collections of vent larvae in the Mariana back-arc, and we will compare the abundances and diversity of larvae to similar work conducted at the Ridge 2000 East Pacific Rise Integrated Studies Site. We will deploy a current meter near the Snail site (on-axis) for preliminary estimates of passive larval transport on the time scale of the cruise. The three study sites are situated in a line perpendicular to the back-arc spreading axis, and thus may be interesting in terms of local dispersal processes. Perhaps more interesting, however, is that the back-arc vents that we will visit are as close as 25 km to known vents on the arc, yet 600 km south of the other known vents in the back-arc. These two

  3. Environmental change and cultural adaptation in the southern Caucasus: latest results from Aghitu-3 Cave, Armenia

    NASA Astrophysics Data System (ADS)

    Kandel, Andrew; Gasparyan, Boris; Bruch, Angela; Nahapetyan, Samvel; Weissbrod, Lior

    2014-05-01

    consisting of fine silt horizons with alternating layers of frost shattered basalt slabs. Pollen shows a change to boreal forest, and the increased presence of pika among the micromammals suggests colder and more barren conditions than today. The wide spectrum of micromammals further points to their likely accumulation by a non-selective raptor such as eagle owl. Fish remains of brown trout confirm the presence of a significant fluvial corridor, likely the nearby Vorotan River. This agrees with the charcoal remains identified thus far, which have the signature of a riparian woodland. The sedimentary sequence ends here, truncated at about 24,000 cal BP by late Holocene deposits of anthropogenic origin.

  4. GEOSS AIP-2 Climate Change and Biodiversity Use Scenarios: Interoperability Infrastructures (Invited)

    NASA Astrophysics Data System (ADS)

    Nativi, S.; Santoro, M.

    2009-12-01

    Transaction server: this component publishes the model outputs. The framework was successfully tested in two use scenarios of the GEOSS AIP-2 Climate Change and Biodiversity WG aiming to predict species distribution changes due to Climate Change factors, with the scientific patronage of the University of Colorado and the University of Alaska. The first scenario dealt with the Pikas specie regional distribution in the Great Basin area (North America). While, the second one concerned the modeling of the Arctic Food Chain species in the North Pole area -the relationships between different environmental parameters and Polar Bears distribution was analyzed. Results are published in the GEOSS AIP-2 web site: http://www.ogcnetwork.net/AIP2develop .

  5. A technology framework to analyse the Climate Change impact on biodiversity species distribution

    NASA Astrophysics Data System (ADS)

    Nativi, S.; Khalsa, S. J.; Geller, G. N.; O'Tuama, E.; Thomas, D.; Mazzetti, P.; Santoro, M.

    2009-04-01

    successfully experimented in the GEOSS Interoperability Process Pilot Project (IP3) and demonstrated at the IV Ministerial summit in Cape Town -November 2007. Presently, the framework is used for the GEOSS Architecture Implementation Pilot project -phase 2. The usage case of the impact of climate change on the distribution of Pikas in North America is presented and discussed. This usage case is based on research being done at the University of Colorado. The used presence datasets were collected by the Scientist and from the GBIF (Global Biodiversity Information Facility) Data Portal. Climate datasets were discovered and collected by the WMO publications and distribution system.

  6. GEOSS AIP-2 Climate Change and Biodiversity Use Scenarios: Interoperability Infrastructures

    NASA Astrophysics Data System (ADS)

    Nativi, Stefano; Santoro, Mattia

    2010-05-01

    publish climate, environmental and biodiversity datasets; e)Ecological Niche Model Server: this component is able to run one or more Ecological Niche Models (ENM) on selected biodiversity and climate datasets; f)Data Access Transaction server: this component publishes the model outputs. This framework was assessed in two use scenarios of GEOSS AIP-2 Climate Change and Biodiversity WG. Both scenarios concern the prediction of species distributions driven by climatological change forecasts. The first scenario dealt with the Pikas specie regional distribution in the Great Basin area (North America). While, the second one concerned the modeling of the Arctic Food Chain species in the North Pole area -the relationships between different environmental parameters and Polar Bears distribution was analyzed. The scientific patronage was provided by the University of Colorado and the University of Alaska, respectively. Results are published in the GEOSS AIP-2 web site: http://www.ogcnetwork.net/AIP2develop.

  7. Vulnerability on the Roof of the World: Resilience to Climate Change and Natural Resource Policies on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Klein, J. A.; Hopping, K. A.; Yeh, E.; Hu, J.; Nyima, Y.; Boone, R.; Galvin, K.; Kang, S.; Ojima, D. S.

    2010-12-01

    Pastoralists on the Tibetan Plateau are a marginalized people living in an extreme environment and may be especially vulnerable as the system approaches critical thresholds. In Tibet, temperatures are increasing several times more than the global average while the frequency and severity of severe snowstorms is predicted to increase. Pastoralists are also experiencing reduced mobility and severe grazing restrictions. We are using interdisciplinary frameworks and methods that include a multifactor ecological experiment, household interviews, remote sensing, and a coupled ecosystem and household decision-making model to examine herder and ecosystem vulnerability to climate change and extreme weather events within the context of changing natural resource policies in China. The fully factorial ecological experiment includes two climate changes (warming and spring snow additions) and two types of grazing (yak and pika). We established the experiment in 2008 within the Tibet Autonomous Region (4,870 m) and are monitoring microclimate, vegetation, nutrient availability, carbon fluxes and stable isotopes. We are investigating the sensitivity of the system, whether it is likely to cross critical thresholds, and how resilient this system may be to predicted climate and land use changes. Semi-structured interviews on indigenous knowledge and vulnerability complement the ecological experimental work. We are asking herders about climatic and ecological change and vulnerability to snow disasters. To integrate our ecological and social findings, we are coupling an ecosystem model to an agent-based pastoral household model. Our results from the experiment and the indigenous knowledge study suggest that Kobresia pygmaea, the dominant species and primary grazing resource, is vulnerable to warming. Snow additions can partially mediate this effect. Herders throughout this region share common knowledge about both climatic and ecological changes, but appear to be more closely attuned to

  8. The Late Pleistocene-Holocene community development in Central and SE-Europe in direct fossil record: scope of the approach, common patterns and inter-regional differences.

    NASA Astrophysics Data System (ADS)

    Horacek, Ivan; Lozek, Vojen

    2010-05-01

    continuous sedimentary sequences from different regions of Czech Republic and Slovakia (850 community samples, 29,800 MNI) and neighbouring countries of Central Europe. Despite common general trends we demonstrated stricking local and regional specificities. Among other they include (a) continuous survival of several woodland elements (Clethrionomys glareolus, Sorex araneus, Micotus subterraneus, Microtus agrestis) throughout Weichselian (including LGM) in the Carpathians, (b) prolonged survival of the glacial elements Ochotona pusilla and Microtus gregalis in Pannonian basin and (c) Dicrostonyx gulielmi in the Carpathian foredeep, contrasting to (d) the early disappearance of them in S-Germany and Bohemia, and (e) similar difference were found also in other cenologic traits. While the glacial communities were nearly homogenous in their structure throughout whole the region, the Holocene development produced a considerable faunal provincialism, which was the most pronounced during Boreal. In contrast to central Europe, the available sequences from the SE-Europe and Asia Minor show only minute faunal changes during the Vistulian and Holocene, no essential rearrangements in community structure were observed (at least as the core species are concerned) and except for Lagurus no glacial immigrant did invade the region. At the same time a degree of local provincialism was continuously high and, in a regional scale, it continuously exceeded that of the Boreal central Europe.

  9. Six new deep-water sternaspid species (Annelida, Sternaspidae) from the Pacific Ocean.

    PubMed

    Salazar-Vallejo, Sergio I; Buzhinskaja, Galina

    2013-01-01

    Most sternaspid species have been described from shallow water, and Caulleryaspis Sendall & Salazar-Vallejo, 2013 includes one deep water species: C. gudmundssoni Sendall & Salazar-Vallejo, 2013 from Iceland. In Sternaspis Otto, 1821, the most speciose genus, most species were described from shallow water and only three thrive in deep water: S. maior Chamberlin, 1919 from the Gulf of California, S. princeps Selenka, 1885 from New Zealand, and S. riestchi Caullery, 1944 from Indonesia. The study of some deep sea sternaspids from the Pacific Ocean in the collections of six research institutions resulted in the discovery of six undescribed species, and for three of them there were abundant materials showing ventro-caudal shield development. Caulleryaspis fauchaldi sp. n. is described based on specimens from Oregon and California; it differs from the known species because it has a shield with rounded anterior margins and its peg chaetae form thin, small spines. Caulleryaspis nuda sp. n. was collected off Oregon; it is unique because its shield lacks a layer of sediment particles firmly attached, but has instead a thin layer of small particles loosely attached. Four other species are newly described in Sternaspis: S. annenkovae sp. n. was collected east off the northern Kurile Islands in about 4,000 m depth; it differs from other species by having a bicolored body, with the introvert darker than the abdomen, and its ventro-caudal shield plates are divergent resulting in a divided fan. The second species, S. maureri sp. n. was found off Peru in 1296-6489 m water depths and in the Southwestern Pacific in 795-3830 m; it resembles S. williamsae sp. n. but differs because its shield has better-developed ribs, the fan has a shallow or indistinct median notch and has lateral notches well-developed. The third species, S. uschakovi sp. n., was found in the Okhotsk Sea in 592-1366 m, off California in 1585 m, Gulf of California in 1200-1274 m, and Western Mexico in 2548 m; it

  10. Six new deep-water sternaspid species (Annelida, Sternaspidae) from the Pacific Ocean

    PubMed Central

    Salazar-Vallejo, Sergio I.; Buzhinskaja, Galina

    2013-01-01

    Abstract Most sternaspid species have been described from shallow water, and Caulleryaspis Sendall & Salazar-Vallejo, 2013 includes one deep water species: C. gudmundssoni Sendall & Salazar-Vallejo, 2013 from Iceland. In Sternaspis Otto, 1821, the most speciose genus, most species were described from shallow water and only three thrive in deep water: S. maior Chamberlin, 1919 from the Gulf of California, S. princeps Selenka, 1885 from New Zealand, and S. riestchi Caullery, 1944 from Indonesia. The study of some deep sea sternaspids from the Pacific Ocean in the collections of six research institutions resulted in the discovery of six undescribed species, and for three of them there were abundant materials showing ventro-caudal shield development. Caulleryaspis fauchaldi sp. n. is described based on specimens from Oregon and California; it differs from the known species because it has a shield with rounded anterior margins and its peg chaetae form thin, small spines. Caulleryaspis nuda sp. n. was collected off Oregon; it is unique because its shield lacks a layer of sediment particles firmly attached, but has instead a thin layer of small particles loosely attached. Four other species are newly described in Sternaspis: S. annenkovae sp. n. was collected east off the northern Kurile Islands in about 4,000 m depth; it differs from other species by having a bicolored body, with the introvert darker than the abdomen, and its ventro-caudal shield plates are divergent resulting in a divided fan. The second species, S. maureri sp. n. was found off Peru in 1296–6489 m water depths and in the Southwestern Pacific in 795–3830 m; it resembles S. williamsae sp. n. but differs because its shield has better-developed ribs, the fan has a shallow or indistinct median notch and has lateral notches well-developed. The third species, S. uschakovi sp. n., was found in the Okhotsk Sea in 592–1366 m, off California in 1585 m, Gulf of California in 1200–1274 m, and Western Mexico

  11. Revision of sternaspis otto, 1821 (polychaeta, sternaspidae).

    PubMed

    Sendall, Kelly; Salazar-Vallejo, Sergio I

    2013-01-01

    To the memory of William Ronald Sendall Sternaspid polychaetes are common and often abundant in soft bottoms in the world oceans. Some authors suggest that only one species should be recognized, whereas others regard a few species as widely distributed in many seas and variable depths from the low intertidal to about 4400 m. There are some problems with species delineation and the distinctive ventro-caudal shield has been disregarded or barely used for identifying species. In order to clarify these issues, the ventral shield is evaluated in specimens from the same locality and its diagnostic potential is confirmed. On this basis, a revision of Sternaspis Otto, 1821 (Polychaeta: Sternaspidae) is presented based upon type materials, or material collected from type localities. The sternaspid body, introvert hooks and shield show three distinct patterns, two genera have seven abdominal segments and tapered introvert hooks, and one genus has eight abdominal segments and spatulate introvert hooks. The ventro-caudal shield has three different patterns: stiff with ribs, and sometimes concentric lines, stiff with feebly-defined ribs but no concentric lines, and soft with firmly adhered sediment particles. Sternaspis is restricted to include species with seven abdominal segments, falcate introvert hooks, and stiff shields, often exhibiting radial ribs, concentric lines or both. Sternaspis includes, besides the type species, Sternaspis thalassemoides Otto, 1821 from the Mediterranean Sea, Sternaspis affinis Stimpson, 1864 from the Northeastern Pacific, Sternaspis africana Augener, 1918, stat. n. from Western Africa, Sternaspis andamanensis sp. n. from the Andaman Sea, Sternaspis costata von Marenzeller, 1879 from Japan, Sternaspis fossor Stimpson, 1853 from the Northwestern Atlantic, Sternaspis islandica Malmgren, 1867 from Iceland, Sternaspis maior Chamberlin, 1919 from the Gulf of California, Sternaspis princeps Selenka, 1885 from New Zealand, Sternaspis rietschi Caullery

  12. Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae)

    PubMed Central

    Sendall, Kelly; Salazar-Vallejo, Sergio I.

    2013-01-01

    Abstract To the memory of William Ronald Sendall Sternaspid polychaetes are common and often abundant in soft bottoms in the world oceans. Some authors suggest that only one species should be recognized, whereas others regard a few species as widely distributed in many seas and variable depths from the low intertidal to about 4400 m. There are some problems with species delineation and the distinctive ventro-caudal shield has been disregarded or barely used for identifying species. In order to clarify these issues, the ventral shield is evaluated in specimens from the same locality and its diagnostic potential is confirmed. On this basis, a revision of Sternaspis Otto, 1821 (Polychaeta: Sternaspidae) is presented based upon type materials, or material collected from type localities. The sternaspid body, introvert hooks and shield show three distinct patterns, two genera have seven abdominal segments and tapered introvert hooks, and one genus has eight abdominal segments and spatulate introvert hooks. The ventro-caudal shield has three different patterns: stiff with ribs, and sometimes concentric lines, stiff with feebly-defined ribs but no concentric lines, and soft with firmly adhered sediment particles. Sternaspis is restricted to include species with seven abdominal segments, falcate introvert hooks, and stiff shields, often exhibiting radial ribs, concentric lines or both. Sternaspis includes, besides the type species, Sternaspis thalassemoides Otto, 1821 from the Mediterranean Sea, Sternaspis affinis Stimpson, 1864 from the Northeastern Pacific, Sternaspis africana Augener, 1918, stat. n. from Western Africa, Sternaspis andamanensis sp. n. from the Andaman Sea, Sternaspis costata von Marenzeller, 1879 from Japan, Sternaspis fossor Stimpson, 1853 from the Northwestern Atlantic, Sternaspis islandica Malmgren, 1867 from Iceland, Sternaspis maior Chamberlin, 1919 from the Gulf of California, Sternaspis princeps Selenka, 1885 from New Zealand, Sternaspis rietschi

  13. Demersal fish assemblages off the Seine and Sedlo seamounts (northeast Atlantic)

    NASA Astrophysics Data System (ADS)

    Menezes, Gui M.; Rosa, Alexandra; Melo, Octávio; Pinho, Mário R.

    2009-12-01

    hypothesis [Isaacs, J.D., Schwartzlose, R.A., 1965. Migrant sound scatterers: interaction with the sea floor. Science 150, 1810-1813]. At both seamounts mesopelagic feeders (e.g., Beryx splendens) dominate the upper-slope assemblages (<800 m), while the mid-slope assemblages (800-1200/1300 m) and the lower-slope assemblages (>1300 m) were dominated by squaliform species (e.g., Centrophorus squamosus, Centroscymnus coelolepis, Etmopterus princeps) along with Mora moro or the Antimora rostrata. The lower abundance of C. squamosus observed at Seine may be a result of the fishing activities in the area, since the species is an important by-catch of the black-scabbard fish fishery in the Madeira archipelago. The slightly higher predominance of scavenger species at Seine in deeper assemblages may be the result of an ecological response favouring this functional group in lower productivity regimes. Especially relevant was the record of large reproductive aggregations of B. splendens and Epigonus telescopus found at the edge of the Sedlo plateau.

  14. Methane Distribution In Plumes Of The South Mariana Back-arc Spreading Center

    NASA Astrophysics Data System (ADS)

    Toki, T.; Hirota, A.; Tsunogai, U.; Gamo, T.; Nakamura, K.; Noguchi, T.; Taira, N.; Oomori, T.; Ishibashi, J.; Utsumi, M.

    2004-12-01

    In the South Mariana Back-arc Spreading Center, two methane plumes were observed in water column based on analysis of methane in seawater samples collected during the R/V Thompson expeditions in 2003 around water depth of 2,700 m over the Fryer site on the ridge-axis seamount (12\\deg57.22N, 143\\deg37.16E, depth: 2,850 m). The estimated end-member isotopic compositions of methane in the two plumes are \\delta13C_{CH4} = -5‰ PDB and -50‰ PDB. These values indicated that the two plumes were originated from the different sources. During YK03-09 cruise using the submersible Shinkai 6500 from October to November in 2003, detailed seafloor observation discovered sulfide chimneys emitting black and clear hydrothermal fluid on the off-axis seamount at Pika site (12°55.15N, 143°36.96E, depth: 2,773 m). The result of analysis of isotopic composition of methane in the hydrothermal fluids recovered from the off-axis hydrothermal vents using WHATS (Water and Hydrothermal Atsuryoku Tight Sampler) was averaged value of -4‰ PDB (standard deviation = 1‰ PDB, n = 3). Hydrothermal fluids from the Fryer site were also sampled and were measured: average value = -6.7‰ PDB, standard deviation = 0.3‰ PDB, n = 3. During the R/V Thompson expeditions in March 2004 using ROV ROPOS, 11 ROPOS dives and CTD-RMS plume surveys were conducted, and newly discovered a huge hydrothermal structure with active fluid venting at Achaean site on the ridge skirt (12°56.37N, 143°37.92E, depth: 2,990 m). The δ ^{13}C_{CH4} value of the fluid sample from the site using ROCS (Rotary Clean Seawater sampler) was -14.7‰ PDB. Analysis of isotopic composition of methane in the plume samples collected using the CTD-hydrocast at water depth of 2,500 m over the Archaean site showed -45‰ PDB. Source of methane (δ ^{13}C_{CH4} = -50‰ PDB), however, in the two plumes of the South Mariana Back-arc Spreading Center has been missing. The δ ^{13}C of methane cannot be considered in sediment

  15. Using a Multi-Method Approach to Examine Social-Ecological Vulnerability to Climate Change and Natural Resource Policies on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Klein, J.; Hopping, K. A.; Yeh, E.; Nyima, Y.; Galvin, K.; Boone, R.; Dorje, T.; Ojima, D. S.

    2012-12-01

    Pastoralists and ecosystems on the Tibetan Plateau are facing a suite of novel stresses. Temperatures are increasing several times more than the global average. The frequency and severity of severe snowstorms, which lead to critical losses of livestock, are also increasing. Pastoralists are also experiencing changes to their livelihood activities, including reduced mobility and severe grazing restrictions. We are using interdisciplinary frameworks and methods that integrate results from a multifactor ecological experiment, household interviews, remote sensing, and a coupled ecosystem and household decision-making model to examine herder and ecosystem vulnerability to climate change and extreme weather events (snow disasters) within the context of changing natural resource management policies in China. The fully factorial ecological experiment includes two climate changes (warming and spring snow additions) and two types of grazing (yak and pika) that are being affected by current policy. We established the experiment in 2008 within the Tibet Autonomous Region. We are monitoring microclimate, vegetation, nutrient availability, ecosystem carbon fluxes and stable isotope signatures of select plant species. Through this experiment, we are investigating the sensitivity of the system, whether it can cross critical thresholds, and how resilient this system may be to predicted future climate and land use changes. Semi-structured, in-depth interviews on indigenous knowledge and vulnerability complement the ecological experimental work. We are asking herders about climate and ecological change and their drivers and are also conducting interviews on vulnerability to snow disasters across a three site, 300-500mm precipitation gradient. We are using remote sensing to identify biophysical landscape change over time. To integrate our ecological and social findings, we are coupling the Savanna ecosystem model to the DECUMA agent-based pastoral household model. Our results to date