bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk for Nonalcoholic Fatty Liver Disease in Hispanic Youth With BMI ≥95th Percentile
Authors: Quirós‐Tejeira Rubén E , Rivera Chantal A , Ziba Taonga T , Mehta Nitesh , Smith C Wayne , Butte Nancy F 
Published: January 2007

ABSTRACTObjectives:To characterize children at risk for nonalcoholic fatty liver disease (NAFLD) and to explore possible mechanisms underlying the development of NAFLD in Hispanic youth with a body mass index ≥95th percentile.Patients and Methods:Hispanic nonoverweight (n = 475) and overweight (n = 517) children, ages 4 to 19 y, were characterized in terms of body composition (dual‐energy x‐ray absorptiometry), maturation (Tanner stage), diet (24‐h recall), physical activity (accelerometry), fitness (maximal oxygen uptake), and biochemical profile (fasting alanine aminotransferase [ALT], glucose, insulin, and lipids; inflammation markers such as adiponectin, leptin, C‐reactive protein, and soluble intercellular adhesion molecule‐1; and total antioxidants) using standard laboratory techniques. Risk for NAFLD was defined by fasting serum ALT values >97.5th percentile for age‐ and sex‐specific reference values.Results:Fasting serum ALT was elevated in 24% of overweight children and in only 4% of nonoverweight children. Therefore, to identify risk factors associated with elevated ALT, the remaining statistical analysis was restricted to the overweight group. The percentage of overweight children with elevated ALT did not differ by sex, age, or Tanner stage. Weight, body mass index, z score, waist‐to‐hip ratio, fat‐free mass, fat mass, and percent truncal fat mass were higher in the overweight children with elevated ALT. Fasting insulin, glucose, and homeostasis model‐insulin resistance were higher in the overweight children with elevated ALT, as were triglycerides, total cholesterol, low‐density lipoprotein, thyroid‐stimulating hormone, and triiodothyronine. Fasting serum leptin, C‐reactive protein, and soluble intercellular adhesion molecule‐1 were significantly higher and adiponectin was lower in the overweight children with elevated ALT.Conclusions:The risk for developing NAFLD was high in the overweight Hispanic children. The proportion of “at risk” children was not influenced by gender, age, or maturation. The risk for elevated ALT was predicted by the severity of obesity, central adiposity, hyperinsulinemia, hypertriglyceridemia, elevated thyroid‐stimulating hormone, and systemic inflammation.
Hepatosplenic T Cell Lymphoma Associated With Infliximab Use in Young Patients Treated for Inflammatory Bowel Disease
Authors: Mackey Ann Corken , Green Lanh , Liang Li‐ching , Dinndorf Patricia , Avigan Mark 
Published: January 2007

ABSTRACTHepatosplenic T cell lymphoma (HSTCL) are rare cancers (≈100 published cases worldwide) and comprise 5% of peripheral T cell lymphomas. As of October 5, 2006, the FDA's Adverse Event Reporting System has received 8 cases of HSTCL in young patients using infliximab, a tumor necrosis factor‐α blocking agent, to treat inflammatory bowel disease (6 of the 8 cases had a fatal outcome). All 8 patients were receiving concomitant immunosuppressant therapy (eg, azathioprine, prednisone). It has not been established that infliximab had an exclusive or primary role in the pathogenesis of these HSTCL cases; however, it appears that patients using this product may be at greater risk for developing this rare lymphoma.
Characterization of a novel Toll/interleukin‐1 receptor (TIR)‐TIR gene differentially expressed in common bean (Phaseolus vulgaris cv. Othello) undergoing a defence response to the geminivirus Bean dwarf mosaic virus
Authors: SEO YOUNG‐SU , JEON JONG‐SEONG , ROJAS MARIA R. , GILBERTSON ROBERT L. 
Published: January 2007

SUMMARYCommon bean (Phaseolus vulgaris L.) cultivar (cv.) Othello develops a hypersensitive response‐associated vascular resistance to infection by Bean dwarf mosaic virus (BDMV), a single‐stranded DNA virus (genus Begomovirus, family Geminiviridae). A PCR‐based cDNA subtraction approach was used to identify genes involved in this resistance response. Eighteen clones, potentially involved with BDMV resistance, were identified based upon being up‐regulated in BDMV‐infected tissues and/or having sequence similarity with known resistance‐associated genes. Analysis of these clones revealed potential genes involved in pathogen defence, including pathogenesis‐related protein genes and resistance gene analogues (RGAs). Further characterization of one RGA, F1‐10, revealed that it encodes a predicted protein with a double Toll/interleukin‐1 receptor (TIR) motif. Full‐length (F1‐10) and spliced (F1‐10sp) forms of the RGA were strongly up‐regulated in BDMV‐infected cv. Othello hypocotyl tissues by 4 days post‐inoculation, but not in equivalent mock‐inoculated tissues. In agroinfiltration experiments, F1‐10, but not F1‐10sp, mediated resistance to BDMV in the susceptible common bean cv. Topcrop. By contrast, transgenic Nicotiana benthamiana lines expressing F1‐10 or F1‐10sp were not resistant to BDMV. Interestingly, when these transgenic lines were inoculated with the potyvirus Bean yellow mosaic virus, some F1‐10 lines showed a more severe symptom phenotype compared with non‐transgenic control plants. Based on these findings, F1‐10 was named: Phaseolus vulgaris VIRUS response TIR‐TIR GENE 1 (PvVTT1).
Ferricrocin synthesis inMagnaporthe griseaand its role in pathogenicity in rice
Authors: HOF CAROLIN , EISFELD KATRIN , WELZEL KAI , ANTELO LUIS , FOSTER ANDREW J. , ANKE HEIDRUN 
Published: January 2007

SUMMARYIron is an essential element for the growth of nearly all organisms. In order to overcome the problem of its low bioavailability, microorganisms (including fungi) secrete siderophores, high‐affinity iron chelators. As the acquisition of iron is also a key step in infection processes, siderophores have been considered as potential virulence factors in several host–pathogen interactions. Most fungi produce siderophores of the hydroxamate‐type, which are synthesized by non‐ribosomal peptide synthetases (NRPSs).Magnaporthe grisea, the causal agent of rice blast disease, produces ferricrocin as intracellular storage siderophore and excretes coprogens. In theM. griseagenome we identifiedSSM1, an NRPS gene, and a gene encoding anl‐ornithine N5‐monooxygenase (OMO1) that is clustered withSSM1and responsible for catalysing the first step in siderophore biosynthesis, the N5hydroxylation of ornithine. Disruption ofSSM1confirmed that the gene encodes ferricrocin synthetase. Pathogenicity of these mutants towards rice was reduced, suggesting a role of this siderophore in pathogenicity ofM. grisea.
Zucchini yellow mosaic virus: insect transmission and pathogenicity —the tails of two proteins
Authors: GAL‐ON AMIT 
Published: January 2007

SUMMARYTaxonomy: Zucchini yellow mosaic virus (ZYMV) is a member of genus Potyvirus, family Potyviridae. ZYMV is a positive‐strand RNA virus. Physical properties: Virions are flexuous filaments of 680–730 nm in length and 11–13 nm in diameter, composed of about 2000 subunits of a single 31‐kDa protein (calculated). The genome RNA size is 9.6 kb covalently linked to a viral‐encoded protein (the VPg) at the 5′ end, and with a 3′ poly A tail. The 5′ end of the sequence is AU‐rich (69%). Viral proteins: The genome is expressed as a polyprotein cleaved by three viral proteases and processed into ten putative mature proteins. The structural coat protein is processed from the carboxyl terminus of the polyprotein and is highly immunogenic. Host and symptoms: Natural and experimental infection has been reported mainly in the Cucurbitaceae. Experimental local lesion hosts include Chenopodium amaranticolour, C. quinoa and Gomphrena globosa. Some ZYMV strains cause symptomless infection as in Ranunculus sardous, Nicotiana benthamiana and Sesamum indicum. ZYMV causes stunting and major foliar deformation with dark green blisters and mosaics in cucurbit hosts, eventually developing a filamentous leaf phenotype. In general, symptoms are severe on cucurbit hosts and cause dramatic reductions in yields due to severe fruit deformation. The virus is present in all the plant tissues at relatively high concentrations (c. 0.1 mg/mL of purified virus per 1 g fresh leaf tissue). The most suitable species for maintenance and purification is Cucurbita pepo. Transmission: ZYMV is efficiently transmitted by aphids in a non‐persistent manner. The coat protein (CP) and the helper component‐protease (HC‐Pro) are required for aphid transmission, through the CP DAG motif and the HC‐Pro KLSC and PTK motifs. Mechanical transmission is efficient both in the laboratory and naturally. Economic importance: ZYMV disease is a major constraint in the production of cucurbits world‐wide. The virus can cause massive damage (to total loss) to cucurbit crops, and prevents the growth of some cucurbit crops in certain areas. Control of ZYMV requires the integration of conventional resistance and transgenic breeding along with cross‐protection technologies.
Functional analysis of NLP genes from Botrytis elliptica
Authors: STAATS MARTIJN , VAN BAARLEN PETER , SCHOUTEN ALEXANDER , VAN KAN JAN A. L. 
Published: January 2007

SUMMARYWe functionally analysed two Nep1‐like protein (NLP) genes from Botrytis elliptica (a specialized pathogen of lily), encoding proteins homologous to the necrosis and ethylene‐inducing protein (NEP1) from Fusarium oxysporum. Single gene replacement mutants were made for BeNEP1 and BeNEP2, providing the first example of transformation and successful targeted mutagenesis in this fungus. The virulence of both mutants on lily leaves was not affected. BeNEP1 and BeNEP2 were individually expressed in the yeast Pichia pastoris, and the necrosis‐inducing activity was tested by infiltration of both proteins into leaves of several monocots and eudicots. Necrotic symptoms developed on the eudicots tobacco, Nicotiana benthamiana and Arabidopsis thaliana, and cell death was induced in tomato cell suspensions. No necrotic symptoms developed on leaves of the monocots rice, maize and lily. These results support the hypothesis that the necrosis‐inducing activity of NLPs is limited to eudicots. We conclude that NLPs are not essential virulence factors and they do not function as host‐selective toxins for B. elliptica.
Biogeochemical interactions between iron and sulphate in freshwater wetlands and their implications for interspecific competition between aquatic macrophytes
Authors: VAN DER WELLE MARLIES E. W. , SMOLDERS ALFONS J.P. , OP DEN CAMP HUUB J.M. , ROELOFS JAN G.M. , LAMERS LEON P.M. 
Published: January 2007

Summary1. Wetlands are threatened by desiccation, eutrophication and changing water quality, generally leading to greatly altered biogeochemical processes. Sulphate pollution can lead to severe eutrophication and sulphide toxicity, but may also interact with the availability of iron and other metals.2. In the present study, we examined the biogeochemical interactions between sulphate and iron availability, and their effects on aquatic macrophytes, in a field experiment with enclosures. The natural iron supply by groundwater was mimicked by adding iron to the sediment, and the effect of increased sulphate concentrations in the surface water was also studied. The enclosure experiment was performed in a mesotrophic, anaerobic ditch in a peat meadow reserve in the Netherlands. In all enclosures, three Stratiotes aloides plants were introduced to serve as indicator species.3. Addition of sulphate led to the mobilisation of phosphate, whereas addition of iron or both iron and sulphate did not affect P mobilisation. Growth of S. aloides was decreased by both iron addition and sulphate addition (sulphide toxicity). Addition of iron under sulphidic conditions, however, led to mutual detoxification of both toxicants (iron and sulphide) and did not decrease S. aloides growth. The uptake of metals was highest in the treatment involving sulphate addition, probably as a result of increased mineralisation of the peat soil.4. Growth of Elodea nuttallii, which grew naturally in the enclosures, was stimulated by iron or iron plus sulphate addition. It did not, however, grow in the enclosures with sulphate addition, as a result of sulphide toxicity or sulphide‐induced iron deficiency. Under iron‐rich conditions, E. nuttallii appeared to be a better competitor than S. aloides and depressed the growth of the latter species.5. We propose that the growth of S. aloides is directly regulated by interactions between sulphide and iron and indirectly by the effects of both compounds on the competitive strength of E. nuttallii. In general, we conclude that biogeochemical interactions between sulphate and iron can have a strong influence on plant species composition in freshwater wetlands, because of direct effects or changes in the competitive strength of plant species related to differential sensitivity to either iron or sulphide.
Ecological relationships between stream communities and spatial scale: implications for designing catchment‐level monitoring programmes
Authors: JOHNSON RICHARD K. , FURSE MIKE T. , HERING DANIEL , SANDIN LEONARD 
Published: January 2007

Summary1. Stream communities are structured by factors acting over multiple spatial and temporal scales. Identifying what factors are driving spatial patterns in stream communities is a central aim of ecology.2. Here we used two large European data sets of fish, invertebrates, macrophytes, benthic diatoms and environmental data in two stream groups (lowland and mountain) to determine the importance of variables at different spatial scales (geographical, regional, local) on community structure.3. Both geographical position and ecoregion were selected first in canonical correspondence analysis (CCA), clearly showing the broad spatial gradients covered in the data set. Secondary predictors (after accounting for spatial and/or ecoregion effects) were similar between stream groups and among the four organism groups. In particular, conductivity and N concentration were strong predictors reflecting catchment land use.4. Using partial CCA, we assessed the individual importance of the three spatial scales on the community structure of the four organism groups in the two stream groups. The majority of among‐site variability (22–29%) was accounted for by local scale variables (e.g. water chemistry and substratum type), with regional and spatial variables accounting 11–13% and 5–6%, respectively. Our findings indicate that the four organism groups are responding similarly to the different levels of spatial scale, implying much redundancy which should be consider when implementing studies of bioassessment.
Fish assemblage patterns in the littoral zone of a European reservoir
Authors: BROSSE SEBASTIEN , GROSSMAN GARY D. , LEK SOVAN 
Published: January 2007

Summary1. Although reservoirs are common aquatic habitats in Europe, there is little quantitative information on the spatial organisation of fish assemblages inhabiting their littoral zones. Consequently, we characterised fish assemblage structure in the littoral zone of a reservoir (Lake Pareloup) in SW France during late spring, summer and early autumn (the growing season).2. We measured the relative abundance of fish weekly, from mid‐May to mid‐October, using point abundance sampling by electrofishing. We identified temporal patterns in assemblage structure using hierarchical cluster analysis, and then characterised the spatial distribution of 17 defined ecospecies using a Kohonen self‐organising map (SOM, an unsupervised Artificial Neural Network).3. Our analyses revealed three distinct faunal structures within the littoral zone. From mid‐May to mid‐July, adults and young‐of‐the‐year (0+) occupied separate habitats, with most 0+ fish in vegetated habitats and adults in open water. From mid‐July to late August, some 0+ co‐occurred with adults, but most 0+ fishes remained in vegetated areas. Finally, from late August to mid‐October, most fish (both 0+ and adults) left the vegetation for unvegetated littoral habitats, the exception being fish species known to be dependent on macrophytes.4. Contrary to patterns for adult fishes, the 0+ fish assemblage was dynamic. These dynamics were driven by ontogenetic species‐specific habitat changes. Consequently, there was little evidence of stable assemblages or strong assemblage–habitat relationships that would be expected of an ‘interactive’ assemblage. It is likely that the patterns observed are a result of species‐specific response to habitat availability in the lake.
Response of river metabolism to restoration of flow in the Kissimmee River, Florida, U.S.A.
Authors: COLANGELO DAVID J. 
Published: January 2007

Summary1. The single station diel oxygen curve method was used to determine the response of system metabolism to backfilling of a flood control canal and restoration of flow through the historic river channel of the Kissimmee River, a sub‐tropical, low gradient, blackwater river in central Florida, U.S.A. Gross primary productivity (GPP), community respiration (CR), the ratio of GPP/CR (P/R) and net daily metabolism (NDM) were estimated before and after canal backfilling and restoration of continuous flow through the river channel.2. Restoration of flow through the river channel significantly increased reaeration rates and mean dissolved oxygen (DO) concentrations from <2 mg L−1 before restoration of flow to 4.70 mg L−1 after flow was restored.3. Annual GPP and CR rates were 0.43 g O2 m−2 day−1 and 1.61 g O2 m−2 day−1 respectively, before restoration of flow. After restoration of flow, annual GPP and CR rates increased to 3.95 O2 m−2 day−1 and 9.44 g O2 m−2 day−1 respectively.4. The ratio of P/R (mean of monthly values) increased from 0.29 during the prerestoration period to 0.51 after flow was restored, indicating an increase in autotrophic processes in the restored river channel. NDM values became more negative after flow was restored.5. After flow was restored, metabolism parameters were generally similar to those reported for other blackwater river systems in the southeast U.S.A. Postrestoration DO concentrations met target values derived from free flowing, minimally impacted reference streams.
Nutrient availability and the carnivorous habit in Utricularia vulgaris
Authors: KIBRIYA SADIA , IWAN JONES J. 
Published: January 2007

Summary1. Carnivory in plants is thought to enhance growth through an increased supply of nutrients, although there are considerable costs involved. It has been assumed that the relative investment of biomass in traps is inversely proportional to the availability of nutrients from non‐carnivorous sources. Our aim was to test the effect of increasing nutrient concentration on investment in carnivory by Utricularia vulgaris.2. Plants were grown under controlled conditions and nitrogen and phosphorus added at three loadings in a crossed design. Investment in carnivory was assessed as the proportion of (i) leaf biomass and (ii) leaf area comprising traps.3. There was no effect of nutrient additions on plant growth or periphyton abundance. Investment in carnivory declined with increasing phosphorus loading. There was no effect of nitrogen, despite this being the nutrient commonly thought to be sought by carnivorous plants. Analysis of previously published data also indicated a decline in investment with increasing P availability.4. Investment in carnivory in U. vulgaris is inversely proportional to the availability of phosphorus from non‐carnivorous sources.
Challenging the tragedy of the commons in root competition: confounding effects of neighbour presence and substrate volume
Authors: SEMCHENKO MARINA , HUTCHINGS MICHAEL J. , JOHN ELIZABETH A. 
Published: January 2007

Summary

It has been claimed that, compared with plants grown without competition, plants competing for a common pool of soil‐based resources overproduce roots at the expense of reproduction (known as the tragedy of the commons). However, experiments on this phenomenon have manipulated not only the presence/absence of neighbours, but also substrate volume. Restricted substrate volume can itself affect plant growth, possibly through chemical self‐inhibition of root growth. We conducted an experiment with oats (Avena sativa) to examine whether the experimental design used in previous studies on the tragedy of the commons in root competition might have confounded the effects of detection of neighbours and substrate volume.
Six treatments combined two factors, namely the presence or absence of activated carbon, and either the presence of a plastic or a mesh partition, or the absence of a partition, between two plants in a pot. Activated carbon was used to adsorb root exudates and reduce their potential effects on root growth. In a seventh treatment, plants were grown alone in pots with half the substrate volume replaced by gravel, to fragment the distribution of available resources.
We observed no tragedy of the commons in a comparison of the performance of plants grown with and without partitions; plants performed equally well in the presence and absence of root competition.
In the treatment with gravel, plants displayed reduced tillering and shoot growth per unit root mass, and an earlier switch to reproduction.
Pot partitioning was associated with inhibition of root growth that was mediated by root exudates. When activated carbon was present, plants in partitioned pots performed better than plants growing with a root competitor.
We conclude that two processes could determine plant growth in the experimental design used in studies of the tragedy of the commons: (i) greater root self‐inhibition in the more limited space of partitioned pots, and (ii) inefficient root placement in larger substrate volumes in unpartitioned pots that are shared with roots of a competitor. These findings provide a new challenge for experimental designs attempting to demonstrate the role of self/non‐self discrimination in root competition.
Effect of resource availability on biparental care, and offspring neural and behavioral development in the California mouse (Peromyscus californicus)
Authors: Bredy Timothy W. , Brown Richard E. , Meaney Michael J. 
Published: January 2007

AbstractMaternal care influences cognitive function in humans, primates and rodents; however, little is known about the effect of biparental care. Environmental factors such as resource availability play an important role in modulating parental investment strategies with subsequent effects on the offspring. Thus, we examined the interaction between foraging demand and biparental care on hippocampal development and novel object recognition in the monogamous, biparental California mouse. We characterized biparental behavior for 15 days in families exposed to either control (ad libitum feeding) or a high‐foraging demand across the weaning period. Adult male offspring were then tested in the open field, and for novel object and place recognition, as well as for hippocampal synaptic density and the expression of genes encoding for subunits of the N‐methyl‐d‐aspartate (NMDA) receptor complex, and the postsynaptic density (PSD)‐95 scaffolding protein. Under high‐foraging demand, the mothers' body weight was decreased at weaning and fathers spent significantly less time in contact with pups. Offspring reared under high‐foraging demand weighed less at weaning and, as adults, were more fearful in the open field and showed profound deficits in both novel object and place recognition. While synaptic density and NR1 mRNA expression were unaffected, offspring reared under high‐foraging demand showed increased NR2A and decreased NR2B mRNA expression. Further, PSD‐95 protein expression was decreased in mice reared under high‐foraging demand. Together, the results suggest that resource availability affects biparental investment strategies, with subsequent effects on hippocampal development and novel object recognition in the offspring.