bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial Scale or Amplitude of Predictors as Determinants of the Relative Importance of Environmental Factors to Plant Community Structure
Authors: Pansonato Marcelo P. , Costa Flávia R. C. , de Castilho Carolina V. , Carvalho Fernanda A. , Zuquim Gabriela 
Published: November 2012

AbstractThe literature on tropical rain forest plant‐community relationships with environmental factors usually does not recognize that the relative importance of environmental factors recorded in each study might be due to their amplitude of variation within sites. Geographic scale, however, is recognized as an important modulator of this relative importance. To disentangle the effects of scale and environmental amplitude, ferns and trees in two landscapes of the same size (each 25 km2) with different soil‐fertility amplitudes but similar soil‐texture range were sampled in central Amazonia. We found that major determinants of community structure were the same for ferns and trees. Texture was the main predictor of community structure in the site with homogeneous soil fertility, while availability of exchangeable cations was the main predictor in the site with a wider fertility range. When both sites were analyzed together, soil fertility was the main predictor of community structure and soil texture segregated floristic subgroups within certain ranges of the soil‐fertility gradient. We conclude that: (1) floristic patterns for trees and ferns are congruent; (2) floristic variation depends on the amplitude of the studied gradients, more than on geographical scale; (3) limiting factors are not necessarily the most important predictors of compositional patterns; and (4) communities are structured hierarchically. Therefore, landscape structure (meaning which combinations of environmental factors, their amplitude of variation and which part of the gradient is found within the landscape) affect our perception of the relative importance that environmental factors will have as predictors of species composition.
Insulin resistance does not affect early embryo development but lowers implantation rate in in vitro maturation–in vitro fertilization–embryo transfer cycle
Authors: Chang Eun M. , Han Ji E. , Seok Hyun H. , Lee Dong R. , Yoon Tae K. , Lee Woo S. 
Published: November 2012

AbstractObjectiveAlthough extensive evidence indicates the hyperinsulinemia directly contributes to reproductive dysfunction in polycystic ovarian syndrome (PCOS), influence of insulin resistance (IR) on assisted reproductive technology outcomes is poorly understood. In this study we aimed to evaluate the effects of IR on in vitro maturation‐in vitro fertilization–embryo transfer (IVM‐IVF‐ET) in patients with PCOS.DesignProspective observational study.PatientsWomen with PCOS (n = 115) commencing IVM.MeasurmentsIR (n = 51) and non‐IR (n = 64) women with PCOS ready to commence an IVM cycle were recruited. IR was diagnosed using the glucose tolerance test (GTT) and homeostasis model assessment (HOMA) index. Patients with an abnormal GTT and/or HOMA index >2·4 were considered IR. Patients underwent 115 cycles of unstimulated hCG‐primed IVM.ResultsMaturation, fertilization, cleavage rates, the number of good‐quality embryo, and blastocyst formation rates were not significantly different between groups. However, implantation (11·6% vs 28·7%, P = 0·001, respectively), clinical pregnancy (23·5% vs 53·1%, P = 0·002, respectively), and ongoing pregnancy rates (21·6% vs 46·9%. P = 0·006, respectively) were significantly decreased in the IR group. The negative effect of IR on pregnancy outcomes remained after controlling for age, body mass index (BMI) and lipid profiles (OR 4·928, 95% CI 1·735–13·991, P = 0·003).ConclusionsPregnancy rate after IVM is impaired in IR patients with PCOS. Oocyte development and embryo quality are not affected, suggesting that the effects of hyperinsulinemia on endometrial function and implantation process underlie the decreased pregnancy rate.
Spatial distribution of Greenland halibut Reinhardtius hippoglossoides in relation to abundance and hypoxia in the estuary and Gulf of St. Lawrence
Authors: Youcef Wahiba Ait , Lambert Yvan , Audet Celine 
Published: November 2012

AbstractAnnual bottom‐trawl surveys (1990–2010) were used to examine associations between environmental conditions, spatial distribution, and size‐specific abundance of Greenland halibut Reinhardtius hippoglossoides in the estuary and Gulf of St. Lawrence (EGSL), and to test the influence of hypoxic conditions on habitat selection. Size classes representing juvenile, immature and adult fish were used for the analyses. The highest concentrations of fish were found in the St. Lawrence estuary at both high and low levels of stock abundance. The areas occupied by 50, 75, and 95% of juvenile fish expanded with higher population abundance. However, contrary to our predictions, densities in marginal habitats did not increase at a higher rate than in optimal habitats. Fish longer than 32 cm were distributed over a broader area than juvenile fish. Their abundance explained a limited proportion of the variability in spatial distribution. The spatial dynamics of Greenland halibut in the EGSL is best described by a proportional density model where the rate of increase in local density is associated with population abundance. Habitats selected by Greenland halibut were characterized by low dissolved oxygen (DO) levels. The strong association between high fish densities and low DO concentrations indicates a high tolerance of Greenland halibut to hypoxia. It also indicates that negative effects, if present, could be compensated by other factors such as food availability and/or refuge from predation. The results of this study also clearly define the St. Lawrence estuary as the major nursery area for the EGSL population.
Impacts of the 2011 mega‐earthquake and tsunami on abalone Haliotis discus hannai and sea urchin Strongylocentrotus nudus populations at Oshika Peninsula, Miyagi, Japan
Authors: TAKAMI HIDEKI , WON NAM‐IL , KAWAMURA TOMOHIKO 
Published: November 2012

AbstractOn 11 March 2011, a massive tsunami generated by a mega‐earthquake with a moment magnitude of 9.0 hit a wide area of Pacific coast of northeast Japan. We observed and analyzed the effects of the earthquake and tsunami event on populations of the abalone Haliotis discus hannai and sea urchin Strongylocentrotus nudus at Tomarihama in Miyagi, where we have carried out regular surveys since January 2008. Before the event, algal forests dominated by the brown macroalga Eisenia bicyclis had developed in the survey area shallower than 5 m in depth, where adult abalone >50 mm in shell length (SL) inhabited. Juvenile abalone <20 mm SL and juvenile and adult urchins inhabited the deeper area dominated by crustose coralline algae (CCA). After the event, although no apparent decrease was observed in the brown macroalgal population, the mean density of adult abalone >50 mm SL, mainly inhabiting the algal forests, was reduced by more than half. The impact of the tsunami was more profound in the CCA area than in the macroalgal forest. Juvenile abalone and urchins largely decreased to 14 and 5% of the densities just before the event, respectively. The distribution pattern of juvenile abalone and urchins could be a cause of the marked decrease, because most of these animals inhabited the CCA area where the disturbance by the massive water movement was not reduced by the effects of the macroalgal forest.
Changes of imidazoline receptors in spontaneously hypertensive rats
Authors: Mar Guang‐Yuan , Chou Ming‐Ting , Chung Hsien‐Hui , Chiu Nien‐Hua , Chen Mei‐Fen , Cheng Juei‐Tang 
Published: November 2012

SummaryThe role of imidazoline receptors in the regulation of vascular function remains unclear. In this study, we evaluated the effect of agmatine, an imidazoline receptor agonist, on systolic blood pressure (SBP) in spontaneously hypertensive rats (SHRs) and investigated the expressions of imidazoline receptors by Western blot. The isometric tension of aortic rings isolated from male SHRs was also estimated. Agmatine decreased SBP in a dose‐dependent manner in SHRs but not in the normal group [Wistar–Kyoto (WKY) rats]. This reduction in SBP in SHRs was abolished by BU224, a selective antagonist of imidazoline I2‐receptors. Higher expression of imidazoline receptors in SHR was observed. Moreover, agmatine‐induced relaxation in isolated aortic rings precontracted with phenylephrine or KCl. This relaxation was also abolished by BU224 but was not modified by efaroxan, an imidazoline I1‐receptor antagonist. Agmatine‐induced relaxation was also attenuated by PNU 37883, a selective blocker of vascular ATP‐sensitive potassium (KATP) channels. Additionally, vasodilatation by agmatine was reduced by an inhibitor of protein kinase A (PKA). We suggest that agmatine can lower blood pressure in SHRs through activation of the peripheral imidazoline I2‐receptor, which is expressed more highly in SHRs.
Ecomarkets for conservation and sustainable development in the coastal zone
Authors: Fujita Rod , Lynham John , Micheli Fiorenza , Feinberg Pasha G. , Bourillón Luis , Sáenz‐Arroyo Andrea , Markham Alexander C. 
Published: November 2012

ABSTRACTBecause conventional markets value only certain goods or services in the ocean (e.g. fish), other services provided by coastal and marine ecosystems that are not priced, paid for, or stewarded tend to become degraded. In fact, the very capacity of an ecosystem to produce a valued good or service is often reduced because conventional markets value only certain goods and services, rather than the productive capacity. Coastal socio‐ecosystems are particularly susceptible to these market failures due to the lack of clear property rights, strong dependence on resource extraction, and other factors. Conservation strategies aimed at protecting unvalued coastal ecosystem services through regulation or spatial management (e.g. Marine Protected Areas) can be effective but often result in lost revenue and adverse social impacts, which, in turn, create conflict and opposition. Here, we describe ‘ecomarkets’ – markets and financial tools – that could, under the right conditions, generate value for broad portfolios of coastal ecosystem services while maintaining ecosystem structure and function by addressing the unique problems of the coastal zone, including the lack of clear management and exclusion rights. Just as coastal tenure and catch‐share systems generate meaningful conservation and economic outcomes, it is possible to imagine other market mechanisms that do the same with respect to a variety of other coastal ecosystem goods and services. Rather than solely relying on extracting goods, these approaches could allow communities to diversify ecosystem uses and focus on long‐term stewardship and conservation, while meeting development, food security, and human welfare goals. The creation of ecomarkets will be difficult in many cases, because rights and responsibilities must be devolved, new social contracts will be required, accountability systems must be created and enforced, and long‐term patterns of behaviour must change. We argue that efforts to overcome these obstacles are justified, because these deep changes will strongly complement policies and tools such as Marine Protected Areas, coastal spatial management, and regulation, thereby helping to bring coastal conservation to scale.
Novel crosstalk between ERK MAPK and p38 MAPK leads to homocysteine‐NMDA receptor‐mediated neuronal cell death
Authors: Poddar Ranjana , Paul Surojit 
Published: November 2012

AbstractHyperhomocysteinemia is an independent risk factor for both acute and chronic neurological disorders, but little is known about the underlying mechanisms by which elevated homocysteine can promote neuronal cell death. We recently established a role for NMDA receptor‐mediated activation of extracellular signal‐regulated kinase (ERK)‐MAPK in homocysteine‐induced neuronal cell death. In this study, we examined the involvement of the stress‐induced MAPK, p38 in homocysteine‐induced neuronal cell death, and further explored the relationship between the two MAPKs, ERK and p38, in triggering cell death. Homocysteine‐mediated NMDA receptor stimulation and subsequent Ca2+ influx led to a biphasic activation of p38 MAPK characterized by an initial rapid, but transient activation followed by a delayed and more prolonged response. Selective inhibition of the delayed p38 MAPK activity was sufficient to attenuate homocysteine‐induced neuronal cell death. Using pharmacological and RNAi approaches, we further demonstrated that both the initial and delayed activation of p38 MAPK is downstream of, and dependent on activation of ERK MAPK. Our findings highlight a novel interplay between ERK and p38 MAPK in homocysteine‐NMDA receptor‐induced neuronal cell death.
Comparison of Freshwater Diatom Assemblages from a High Arctic Oasis to Nearby Polar Desert Sites and Their Application to Environmental Inference Models
Authors: Michelutti Neal , McCleary Kathryn , Douglas Marianne S.V. , Smol John P. 
Published: November 2012

Arctic oases are regions of atypical warmth and relatively high biological production and diversity. They are small in area (<5 km2) and uncommon in occurrence, yet they are relatively well studied due to the abundance of plant and animal life contained within them. A notable exception is the lack of research on freshwater ecosystems within polar oases. Here, we aim to increase our understanding of freshwater diatom ecology in polar oases. Diatoms were identified and enumerated from modern sediments collected in 23 lakes and ponds contained within the Lake Hazen oasis on Ellesmere Island, and compared with diatom assemblages from 29 sites located outside of the oasis across the northern portion of the island. There were significant differences in water chemistry variables between oasis and northern sites, with oasis sites having higher conductivity and greater concentrations of nutrients and related variables such as dissolved organic carbon (DOC). Taxa across all sites were typical of those recorded in Arctic freshwaters, with species from the genera Achnanthes sensu lato, Fragilaria sensu lato, and Nitzschia dominating the assemblages. A correspondence analysis (CA) ordination showed that oasis sites generally plotted separately from the northern sites, although the sites also appear to plot separately based on whether they were lakes or ponds. Canonical correspondence analysis (CCA) identified specific conductivity, DOC, and SiO2 as explaining significant (P < 0.05) and additional amounts of variation in the diatom data set. The most robust diatom‐based inference model was generated for DOC, which will provide useful reconstructions on long‐term changes in paleo‐optics of high Arctic lakes.
Clonal traits outperform foliar traits as predictors of ecosystem function in experimental mesocosms
Authors: Bittebiere Anne‐Kristel , Clément Bernard , Mony Cendrine 
Published: November 2012

AbstractQuestionsIs productivity linked with clonal traits through their indirect effect on competitive interactions? Are clonal traits better predictors of productivity than foliar traits?LocationRennes, France.MethodsWe used a wide‐scale mesocosm experiment based on several assemblages of species differing in clonal traits, and evaluated if the relationship between biomass production and clonal traits is consistent at different ecological scales.ResultsResults showed that at the individual level, foliar traits were independent from clonal traits in most studied species. Community specific above‐ground net primary productivity was significantly correlated to community‐aggregated values of clonal and foliar traits. Nevertheless, a stronger relationship with clonal traits was indicated, emphasizing a plant foraging strategy along the horizontal plant plane, which was a determinant of community productivity. An inverse relationship between clonal traits and biomass production was observed at the individual and community levels, which was attributed to modifications in resource acquisition processes resulting from competitive interactions.ConclusionsWe demonstrated that clonal traits are correlated with productivity at the individual and community scales. These traits were indicators of resource acquisition processes mediated through competitive interactions.
Nerve growth factor induced after temporomandibular joint inflammation decelerates chondrocyte differentiation
Authors: Huang H , Shank G , Ma L , Tallents RH , Kyrkanides S 
Published: November 2012

ObjectiveThe goal of this study was to investigate changes in nerve growth factor (NGF) and its high‐affinity receptor‐tropomyosin receptor kinase A (TrkA) expression in the TMJ after intra‐articular inflammation.Materials and MethodsWe employed the Col1‐IL1βXAT inducible model of joint inflammation. Changes in NGF and TrkA expression were evaluated by immunohistochemistry. The function of NGF on cell differentiation was assessed in vitro employing the ATDC5 chondrocyte cell line.ResultsNGF expression was observed in articular chondrocytes only after TMJ inflammation, whereas TrkA expression was detected in articular chondrocytes under both naïve as well as inflamed conditions. The potential effect of NGF on articular chondrocytes was studied on the ATDC5 cell line, whereby NGF decelerated the maturation rate of this chondrogenic cell line, presumably by arresting cell differentiation at the prehypertrophic stage of chondrocyte maturation.ConclusionsNGF‐TrkA signaling in the TMJ provides potentially a means of protection against the development of osteoarthritis by decelerating chondrocyte differentiation. This discovery may lead to the development of novel therapies for osteoarthritis of the TMJ and other joints.
Class II‐specific histone deacetylase inhibitors MC1568 and MC1575 suppress IL‐8 expression in human melanoma cells
Authors: Venza I. , Visalli M. , Oteri R. , Cucinotta M. , Teti D. , Venza M. 
Published: November 2012

SummaryHere, we explored the effects of the novel class II‐specific histone deacetylase inhibitors (HDACis) MC1568 and MC1575 on interleukin‐8 (IL‐8) expression and cell proliferation in cutaneous melanoma cell line GR‐M and uveal melanoma cell line OCM‐3 upon stimulation with phorbol 12‐myristate 13‐acetate (PMA). We found that PMA upregulated IL‐8 transcription via the AP‐1 binding site and identified c‐Jun as the transcription factor involved in this eventS. MC1568 and MC1575 inhibited IL‐8 levels and cell proliferation in either unstimulated or PMA‐stimulated melanoma cells. They acted by suppressing (i) c‐Jun binding to the IL‐8 promoter, (ii) recruitment of histones 3 and 4, RNA polymerase II and TFIIB to the c‐Jun promoter, and (iii) c‐Jun expression. Our findings provide new insights into mechanisms underlying anti‐tumoral activities of class II‐specific HDACis in human melanoma and suggest that they may constitute a novel therapeutic strategy for improving the treatment of this cancer.
The C57Bl/6 mouse serves as a suitable model of human skeletal muscle mitochondrial function
Authors: Jacobs Robert A. , Díaz Víctor , Meinild Anne‐Kristine , Gassmann Max , Lundby Carsten 
Published: November 2012

New Findings
What is the central question of this study?Do mouse skeletal muscle mitochondria resemble human skeletal muscle mitochondria sufficiently to serve as a proper model and how do differences of skeletal muscle type affect the comparison?
What is the main finding and its importance?We find that mouse skeletal muscle respiratory capacity and control function rather similar to human m. vastus lateralis, with the mouse quadricep being overall the most similar. This resemblance is not universal, however, because the coupling control of electron transport during fat oxidation in type I murine muscle is more comparable to human vastus lateralis.
It is debatable whether differences in mitochondrial function exist across skeletal muscle types and whether mouse skeletal muscle mitochondrial function can serve as a valid model for human skeletal muscle mitochondrial function. The aims of this study were to compare and contrast three different mouse skeletal muscles and to identify the mouse muscle that most closely resembles human skeletal muscle respiratory capacity and control. Mouse quadriceps (QUADM), soleus (SOLM) and gastrocnemius (GASTM) skeletal muscles were obtained from 8‐ to 10‐week‐old healthy mice (n= 8), representing mixed, oxidative and glycolytic muscle, respectively. Skeletal muscle samples were also collected from young, active, healthy human subjects (n= 8) from the vastis lateralis (QUADH). High‐resolution respirometry was used to examine mitochondrial function in all skeletal muscle samples, and mitochondrial content was quantified with citrate synthase activity. Mass‐specific respiration was higher across all respiratory states in SOLM versus both GASTM and QUADH (P < 0.01). When controlling for mitochondrial content, however, SOLM respiration was lower than GASTM and QUADH (P < 0.05 and P < 0.01, respectively). When comparing respiratory capacity between mouse and human muscle, QUADM exhibited only one different respiratory state when compared with QUADH. These results demonstrate that qualitative differences in mitochondrial function exist between different mouse skeletal muscles types when respiratory capacity is normalized to mitochondrial content, and that skeletal muscle respiratory capacity in young, healthy QUADM does correspond well with that of young, healthy QUADH.