bluuebunny/crossref_metadata_2025_split huggingface dataset:
Afferent Arteriolar Dilation to 11, 12‐EET Analogs Involves PP2A Activity and Ca2+‐Activated K+ Channels
Authors: Imig John D. , Dimitropoulou Christiana , Reddy D. Sudarshan , White Richard E. , Falck John R. 
Published: February 2008

ABSTRACTThe epoxygenase metabolite, 11, 12‐epoxyeicosatrienoic acid (11, 12‐EET), has renal vascular actions. 11, 12‐EET analogs have been developed to determine the structure activity relationship for 11, 12‐EET and as a tool to investigate signaling mechanisms responsible for afferent arteriolar dilation. We hypothesized that 11, 12‐EET mediated afferent arteriolar dilation involves increased phosphoprotein phosphatase 2A (PP2A) and large‐conductance calcium activated K+ (KCa) channels. We evaluated the chemically and/or metabolically table 11, 12‐EET analogs: 11, 12‐EET‐N‐methylsulfonimide (11, 12‐EET‐SI), 11‐nonyloxy‐undec‐8(Z)‐enoic acid (11, 12‐ether‐EET‐8‐ZE), and 11, 12‐trans‐oxidoeicosa‐8(Z)‐eonoic acid (11, 12‐tetra‐EET‐8‐ZE). Afferent arteriolar responses were assessed. Activation of KCa channels by 11, 12‐EET analogs were established by single cell channel recordings in renal myocytes. Assessment of renal vascular responses revealed that 11, 12‐EET analogs increased afferent arteriolar diameter. Vasodilator responses to 11, 12‐EET analogs were abolished by K+ channel or PP2A inhibition. 11, 12‐EET analogs activated renal myocyte large‐conductance KCa channels. 11, 12‐EET analogs increased cAMP by 2‐fold and PP2A activity increased 3–8 fold in renal myocytes. PP2A inhibition did not significantly affect the 11, 12‐EET analog mediated increase in cAMP and PP2A increased renal myocyte KCa channel activity to a much greater extent than PKA. These data support the concept that 11, 12‐EET utilizes PP2A dependent pathways to activate large‐conductance KCa channels and dilate the afferent arteriole.
Automated Method for Tracking Vast Numbers of FITC‐Labeled RBCs in Microvessels of Rat Brain In Vivo Using a High‐Speed Confocal Microscope System
Authors: Tomita Minoru , Osada Takashi , Schiszler Istvan , Tomita Yutaka , Unekawa Miyuki , Toriumi Haruki , Tanahashi Norio , Suzuki Norihiro 
Published: February 2008

ABSTRACTHigh‐speed camera investigation of rapidly moving red blood cells (RBCs) in the microvasculature has been limited by an inability to handle the vast volume of data. We have developed a novel method to analyze large numbers of RBC images captured by a high‐resolution, high‐speed camera fitted on a confocal fluorescence microscope, to determine the velocities of individual RBCs in capillaries in vivo. Fluorescein isothiocyanate (FITC)‐labeled RBCs flowing in the microvasculature of the cerebral cortex of urethane‐anesthetized Wistar rats were recorded through the skull window on video clips during specified periods at high frame rates (500 fps). Sequential frames of moving RBCs in the video clips for a specified period were analyzed offline with in‐house software (KEIO‐IS2). Images of RBCs acquired were numbered automatically in order of appearance and displayed in a two‐dimensional (2‐D) RBC tracking map. The velocities of individual RBCs were automatically computed based on the RBC displacement per frame multiplied by the frame rate (fps), and the results were displayed in a 2‐D velocity map and a 2‐D RBC number map. Single capillaries were identified by staining with FITC‐dextran. The mean capillary velocity of RBCs was evaluated as 2.05 ± 1.59 mm/second in video clips obtained at 500 fps. This method is considered to have wide potential applicability.
Redirection of Flavonoid Biosynthesis through the Down-Regulation of an Anthocyanidin Glucosyltransferase in Ripening Strawberry Fruit
Authors: Griesser Markus , Hoffmann Thomas , Bellido Mari Luz , Rosati Carlo , Fink Barbara , Kurtzer Robert , Aharoni Asaph , Muñoz-Blanco Juan , Schwab Wilfried 
Published: February 2008

Abstract
Strawberry (Fragaria × ananassa) fruit contains several anthocyanins that give the ripe fruits their attractive red color. The enzyme that catalyzes the formation of the first stable intermediate in the anthocyanin pathway is anthocyanidin-3-O-glucosyltransferase. A putative glycosyltransferase sequence (FaGT1) was cloned from a strawberry fruit cDNA library and the recombinant FaGT1 transferred UDP-glucose to anthocyanidins and, to a lesser extent, flavonols, generating the respective 3-O-glucosides. Quantitative polymerase chain reaction revealed that transcripts of FaGT1 were almost undetectable in green fruits, but gene expression increased dramatically in both turning and ripe red fruit, corresponding closely to the accumulation of anthocyanins during fruit ripening. The expression of FaGT1 is fruit associated and negatively regulated by auxin. To elucidate the in planta function of FaGT1, Agrobacterium tumefaciens cells harboring an intron-hairpin construct of a partial FaGT1 sequence were injected into midsized ripening fruits. In about one-third of the injected fruits, this led to significant down-regulation of FaGT1 transcript levels that corresponded to reduced concentrations of anthocyanin pigments in ripe strawberry fruits. In contrast, significant levels of epiafzelechin—formed by anthocyanidin reductase (ANR) from pelargonidin—were identified in FaGT1-silenced fruits, indicating competition of FaGT1 and FaANR for the common anthocyanidin substrate. Thus, FaGT1 represents an important branching-point enzyme because it is channeling the flavonoid pathway to anthocyanins. These results demonstrate a method to redirect the anthocyanin biosynthesis into flavan-3-ol production to increase the levels of bioactive natural products or modify pigments in plant tissues.
Identification of Negative cis-Acting Elements in Response to Copper in the Chloroplastic Iron Superoxide Dismutase Gene of the Moss Barbula unguiculata
Authors: Nagae Miwa , Nakata Masaru , Takahashi Yohsuke 
Published: February 2008

Abstract
Superoxide dismutases (SODs) are ubiquitous metalloenzymes that catalyze the dismutation of superoxide radicals. Chloroplasts have two isozymes, copper/zinc SOD (Cu/ZnSOD) and iron SOD (FeSOD), encoded by nuclear genes. Because bryophytes are considered as the earliest land plants, they are one of the most interesting plant models for adaptation against oxidative stress. In a previous study, we found that the FeSOD gene was expressed under Cu-deficient conditions and repressed under high-Cu-supply conditions; on the other hand, the Cu/ZnSOD gene was induced by Cu in a moss, Barbula unguiculata. The expression of Cu/ZnSOD and FeSOD is coordinately regulated at the transcriptional level depending on metal bioavailability. Here, using transgenic moss plants, we determined that the GTACT motif is a negative cis-acting element of the moss FeSOD gene in response to Cu. Furthermore, we found that a plant-specific transcription factor, PpSBP2 (for SQUAMOSA promoter-binding protein), and its related proteins bound to the GTACT motif repressed the expression of the FeSOD gene. The moss FeSOD gene was negatively regulated by Cu in transgenic Nicotiana tabacum plants, and the Arabidopsis thaliana FeSOD gene promoter containing the GTACT motif was repressed by Cu. Our results suggested that molecular mechanisms of GTACT motif-dependent transcriptional suppression by Cu are conserved in land plants.
Single nucleotide polymorphisms refine QTL intervals for hip joint laxity in dogs
Authors: Zhu L. , Zhang Z. , Feng F. , Schweitzer P. , Phavaphutanon J. , Vernier‐Singer M. , Corey E. , Friedenberg S. , Mateescu R. , Williams A. , Lust G. , Acland G. , Todhunter R. 
Published: February 2008

SummaryHip laxity is one characteristic of canine hip dysplasia (CHD), an inheritable disease that leads to hip osteoarthritis. Using a genome‐wide screen with 250 microsatellites in a crossbreed pedigree of 159 dysplastic Labrador retrievers and unaffected greyhounds, we previously identified putative (P < 0.01) QTL on canine chromosomes 11 and 29 (CFA11 and CFA29). To refine these QTL locations, we have genotyped 257 dogs including 105 Labrador retrievers, seven greyhounds, four generations of their crossbreed offspring and three German shepherds for 111 and 171 SNPs on CFA11 and CFA29 respectively. The distraction index (DI, a measure of maximum hip laxity) was used as an intermediate phenotype that predicts whether a hip joint will or will not develop osteoarthritis. Using a multipoint linkage analysis, significant evidence (95% posterior probability) was found for QTL contributing to hip laxity in the 16.2–21 cM region on CFA11 that explained 15–18% of the total variance in DI. Evidence for an independent QTL on CFA29 was weaker than that on CFA11. Identification of the causative mutation(s) will lead to better understanding of biochemical pathways in both dogs and humans with hip laxity and dysplasia.
SNP‐finding in pig mitochondrial ESTs
Authors: Scheibye‐Alsing K. , Cirera S. , Gilchrist M. J. , Fredholm M. , Gorodkin J. 
Published: February 2008

SummaryThe Sino‐Danish pig genome project produced 685 851 ESTs (Gorodkin et al. 2007), of which 41 499 originated from the mitochondrial genome. In this study, the mitochondrial ESTs were assembled, and 374 putative SNPs were found. Chromatograms for the ESTs containing SNPs were manually inspected, and 112 total (52 non‐synonymous) SNPs were found to be of high confidence (five of them are close to disease‐causing SNPs in humans). Nine of the high‐confidence SNPs were tested experimentally, and eight were confirmed. The SNPs can be accessed online at http://pigest.ku.dk/more/mito.
Genetic divergence and ecological specialisation of seed weevils (Exapion spp.) on gorses (Ulex spp.)
Authors: BARAT MYRIAM , TARAYRE MICHÈLE , ATLAN ANNE 
Published: February 2008

Abstract 1. Reproductive isolation of sympatric populations may result from divergent selection of populations in different environments, and lead to ecological specialisation. In Brittany (France), the gorse Ulex europaeus (Fabaceae, Genisteae), may be encountered in sympatry with one of the two other gorse species present: U. gallii and U. minor. A recent study based on morphological identification of seed predators of gorse has shown that two weevil species (Curculionoidea, Apionidae) infest gorse pods at different seasons and have different host ranges: Exapion ulicis infests U. europaeus in spring, whereas E. lemovicinum infests U. gallii and U. minor in autumn. Weevil populations may thus have diverged in sympatry.2. As morphological identification of weevils is often difficult and some of the characters used may exhibit individual or environmental variation, mitochondrial and nuclear sequences of weevils collected within pods of the three gorse species in 10 populations of Brittany were used to reconstruct their phylogeny.3. The results reveal that species differentiation based on morphological characters is confirmed by the two molecular data sets, showing that E. ulicis and E. lemovicinum are distinct species, and suggesting the absence of host races. Finally, E. ulicis was able to use U. gallii and U. minor pods in spring in some years in some populations, which appeared to depend on the availability of pods present during its reproductive period.4. Divergence between E. ulicis and E. lemovicinum may have resulted from temporal isolation of reproductive periods of weevil populations followed by specialisation of insects to host phenology.
Strategic ejaculation in the egg parasitoid Trichogramma turkestanica (Hymenoptera: Trichogrammatidae)
Authors: MARTEL VÉRONIQUE , DAMIENS DAVID , BOIVIN GUY 
Published: February 2008

Abstract 1. Several parameters influence sperm allocation by males, including their size and sperm stock, intra‐specific variability, quality of females’, as well as the risk and intensity of sperm competition.2. Models predict that males should invest the maximum ejaculate size when sperm competition intensity is low. As sperm competition intensity increases, males should decrease the number of sperm transferred during mating.3. This decrease in sperm transfer to females occurs because the benefits gained by males with each extra unit of expenditure on sperm decrease. When sperm supply is not unlimited, males could expect a better return by keeping some or all sperm for mating under lower competition intensity.4. In this study, the ejaculate size of males that were kept in groups of one, five or 10 males prior to mating, has been investigated in the haplodiploid egg parasitoid Trichogramma turkestanica Meyer (Hymenoptera: Trichogrammatidae).5. As predicted by theory, the number of sperm transferred decreased significantly with an increase in the number of rivals.6. This is the first study showing strategic sperm allocation depending on sperm competition intensity in a parasitoid.
Neither the devil nor the deep blue sea: larval mortality factors fail to explain the abundance and distribution ofTischeria ekebladella
Authors: GRIPENBERG SOFIA , ROSLIN TOMAS 
Published: February 2008

Abstract1. The distribution, abundance and population dynamics of herbivorous insects may be affected by trophic interactions, by abiotic influences, or by intra‐specific processes. Relatively little is known about how trophic influences vary across space. Here, we investigate spatial variation in mortality in the oak‐feeding leaf minerTischeria ekebladellaas attributable to individual causal agents.2. Leaf miners were experimentally introduced on 67 trees on an island 5 km2in area in south‐western Finland. On each tree, some larvae were protected by a muslin bag, others by a glue barrier around the branch and some left exposed.3. In the bagged transplants, 78.4% of larvae survived, compared with only 9.6% in the other two treatments. Most of the mortality was because of airborne agents: mortality on branches sheltered by a glue barrier was as high as on fully exposed branch tips.4. We consider mortality caused by parasitoid wasps to be the main source of larval death and the primary factor driving general patterns of survival. The effects of bird predation and premature leaf abscission were negligible.5. We detected spatial aggregation in larval survival and parasitism rates at the level of individual trees, but not across the landscape.6. Spatial variation in overall leaf miner survival, parasitism and leaf abscission does not suffice to explain patterns of incidence and abundance of wildT. ekebladellaon experimental trees. Rather, we identify metapopulation dynamics as a likely determinant of the spatial distribution ofT. ekebladellain the landscape.
Improving light‐based geolocation by including sea surface temperature
Authors: NIELSEN ANDERS , BIGELOW KEITH A. , MUSYL MICHAEL K. , SIBERT JOHN R. 
Published: February 2008

AbstractAn approach to integrate sea surface temperature (SST) measurements into estimates of geolocations calculated by changes in ambient light level from data downloaded from pop‐up satellite archival tags (PSAT) is presented. The model is an extension of an approach based on Kalman filter estimation in a state‐space model. The approach uses longitude and latitude estimated from light, and SST. The extra information on SST is included in a consistent manner within the milieu of the Kalman filter. The technique was evaluated by attaching PSATs directly on thermistor‐equipped global positioning system drifter buoys. SSTs measured in the PSATs and drifter buoy were statistically compared with SSTs determined from satellites. The method is applied to two tracks derived from PSAT‐tagged blue sharks (Prionace glauca) in the central Pacific Ocean. The inclusion of SST in the model produced substantially more probable tracks with lower prediction variance than those estimated from light‐level data alone.
Evidence of density‐dependent effects on population variation of Japanese sardine (Sardinops melanosticta) off Korea
Authors: KIM JIN YEONG , KIM SUAM , CHOI YOUNG MIN , LEE JAE BONG 
Published: February 2008

AbstractInterannual variation of some biological parameters for the Japanese sardine, Sardinops melanosticta, population in Korean waters was investigated using scientific surveys and fisheries information since the late 1970s. The abundance and geographical coverage of sardine eggs were high (peak in 1986) and broad when spawning biomasses were high in the mid 1980s, and vice versa in the late 1970s and the early 1990s. Also, feeding and spawning areas based on fisheries information exhibited the same pattern of expansion/contraction as seen in ichthyoplankton surveys. Annual Gonadal Somatic Index (GSI) in spawning season (February to April) and the size at age 1 of sardine were reduced during the high abundance period. It is suggested that density‐dependent effects on the reproduction and growth of the sardine population in Korean waters existed.
Special regulatory T‐cell review: T‐cell dependent suppression revisited
Authors: Basten Antony , Fazekas de St Groth Barbara 
Published: February 2008

SummaryThe concept of T‐cell dependent regulation of immune responses has been a central tenet of immunological thinking since the delineation of the two cell system in the 1960s. Indeed T‐cell dependent suppression was discovered before MHC restriction. When reviewing the data from the original wave of suppression, it is intriguing to reflect not just on the decline and fall of suppressor T cells in the 1980s, but on their equally dramatic return to respectability over the past decade. Hopefully their resurgence will be supported by solid mechanistic data that will underpin their central place in our current and future understanding of the immune system.
Cannon to right of them, Cannon to left of them, Cannon in front of them Volley’d and thunder’d Storm’d at with shot and shell, Boldly they rode and well, Into the jaws of Death, Into the mouth of Hell, Rode the six hundred (suppressionists). (Adapted from The Charge of the Light Brigade, Alfred, Lord Tennyson)
Special regulatory T‐cell review: regulation of immune responses – examining the role of T cells
Authors: Simpson Elizabeth 
Published: February 2008

SummaryThe history of regulatory T cells goes back to the realisation that T cells could provide ‘help’ for antibody responses: the obverse of this is their ability to hold them in check. This brief personal overview follows the initial designation of T cells as ‘suppressor’ and the various hypotheses, some now disproved, put forward for their mechanism of action. We now cautiously label them T regulatory cells, but realise they do not control not all immune regulation. They probably operate through several mechanisms, and some of these are discussed.
Giant Holocene Freshwater Microbialites, Laguna Bacalar, Quintana Roo, Mexico
Authors: GISCHLER EBERHARD , GIBSON MICHAEL A. , OSCHMANN WOLFGANG 
Published: February 2008

AbstractWith more than 10 km of total length, Holocene microbialites in Laguna Bacalar, Mexico, belong to the largest freshwater microbialite occurrences. Microbialites include domes, ledges and oncolites. Domal forms can grow to diameters and heights of 3 m. Microbialites are composed of low magnesium calcite which is, to a large extent, precipitated due to the metabolic activity of the cyanobacteria Homeothrix and Leptolyngbya, and associated diatoms. Photosynthesis removes carbon dioxide and triggers carbonate precipitation. Also, an elevated carbonate concentration in lagoon waters, derived from dissolution of Cenozoic limestone in a karst system, supports carbonate precipitation. Trapping and binding of detrital grains is also observed, but is not as common as precipitation. Bacalar microbialites are largely thrombolitic, however, stromatolitic sections occur as well. The bulk of Bacalar microbialites probably formed in the Late Holocene (ca 1 kyr BP until present). According to 14C dating, microbialites accreted 9 to 8 cal kyr BP; however, these ages may be too old as a result of a strong hard water effect. This effect is seen in 14C ages of living bivalve and gastropod mollusc shells from Bacalar Lagoon, which are 8 to 7 cal kyr BP. The modern associated fauna of microbialites is characterized by low diversity and high abundance of the bivalve mollusc Dreissena sp. and the gastropod Pomacea sp. The abundant grazing gastropods presumably hamper modern microbialite formation. A comparison of Bacalar microbialites with other modern microbialite occurrences worldwide shows only a few patterns: sizes, shapes, microbial taxa, mineralogy, type of accretion and settings including water properties of microbialite occurrences exhibit high variability. A trend may be seen in the grazing metazoa, which are rare to absent in the marine and brackish examples, but apparently present in all the freshwater occurrences of microbialites. Also, freshwater examples are usually characterized by elevated concentrations of carbonate and/or calcium ions in the surrounding waters.
Interplay between JA, SA and ABA signalling during basal and induced resistance against Pseudomonas syringae and Alternaria brassicicola
Authors: Flors Victor , Ton Jurriaan , Van Doorn Ronald , Jakab Gabor , García‐Agustín Pilar , Mauch‐Mani Brigitte 
Published: February 2008

SummaryWe have examined the role of the callose synthase PMR4 in basal resistance and β‐aminobutyric acid‐induced resistance (BABA‐IR) of Arabidopsis thaliana against the hemi‐biotrophic pathogen Pseudomonas syringae and the necrotrophic pathogen Alternaria brassicicola. Compared to wild‐type plants, the pmr4‐1 mutant displayed enhanced basal resistance against P. syringae, which correlated with constitutive expression of the PR‐1 gene. Treating the pmr4‐1 mutant with BABA boosted the already elevated levels of PR‐1 gene expression, and further increased the level of resistance. Hence, BABA‐IR against P. syringae does not require PMR4‐derived callose. Conversely, pmr4‐1 plants showed enhanced susceptibility to A. brassicicola, and failed to show BABA‐IR. Wild‐type plants showing BABA‐IR against A. brassicicola produced increased levels of JA. The pmr4‐1 mutant produced less JA upon A. brassicicola infection than the wild‐type. Blocking SA accumulation in pmr4‐1 restored basal resistance, but not BABA‐IR against A. brassicicola. This suggests that the mutant’s enhanced susceptibility to A. brassicicola is caused by SA‐mediated suppression of JA, whereas the lack of BABA‐IR is caused by its inability to produce callose. A. brassicicola infection suppressed ABA accumulation. Pre‐treatment with BABA antagonized this ABA accumulation, and concurrently potentiated expression of the ABA‐responsive ABI1 gene. Hence, BABA prevents pathogen‐induced suppression of ABA accumulation, and sensitizes the tissue to ABA, causing augmented deposition of PMR4‐derived callose.
Chromosomal rearrangements and genetic structure at different evolutionary levels of theSorex araneusgroup
Authors: BASSET P. , YANNIC G. , HAUSSER J. 
Published: February 2008

AbstractRobertsonian (Rb) fusions received large theoretical support for their role in speciation, but empirical evidence is often lacking. Here, we address the role of Rb rearrangements on the genetic differentiation of the karyotypically diversified group of shrews,Sorex araneus. We compared genetic structure between ‘rearranged’ and ‘common’ chromosomes in pairwise comparisons of five karyotypic taxa of the group. Considering all possible comparisons, we found a significantly greater differentiation at rearranged chromosomes, supporting the role of chromosomal rearrangements in the general genetic diversification of this group. Intertaxa structure and distance were larger across rearranged chromosomes for most of the comparisons, although these differences were not significant. This last result could be explained by the large variance observed among microsatellite‐based estimates. The differences observed among the pairs of taxa analysed support the role of both the hybrid karyotypic complexity and the level of evolutionary divergence.