bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual Signaling during Mating in Brown‐headed Cowbirds (Molothrus ater, Family Emberizidae/Icterinae)
Authors: West Meredith J. , King Andrew P. , Freeberg Todd M. 
Published: May 2010

AbstractMale brown‐headed cowbirds (Molothrus ater) vocalize to females during pair formation, a period usually lasting several days. Males also vocalize to females in the seconds immediately prior to females' adopting copulatory postures. The two major classes of male vocalizations occurring during courtship and copulation are songs and flight whistles. Observations across the species' North American range suggest that the function of these two courtship vocalizations may differ geographically. Aviary observations of eastern and midwestern populations suggested, furthermore, that the precise timing of song and whistle used during copulation sequences differs, with flight whistles occurring most often after a copulatory posture but before the male mounts and the pair copulates. Such timing of the two signals suggested different proximate functions. Here, we report three experiments that addressed the communicative properties of the two signals in two midwestern populations. First, we tested females of the two populations in two playback experiments to determine copulatory responsiveness and discrimination of the two signals. We asked whether females of the two populations gave more copulatory responses to the playbacks of songs and flight whistles of males of their own population than to those of males of the other population, and whether females responded differently to songs than to whistles. In the third experiment, we observed courtship interactions among males and females from one population in a large aviary to assess the use of flight whistles in relation to courtship success. Females of both populations responded more frequently to playbacks of songs than to playbacks of flight whistles and showed reliably more responsiveness to local song variants. Thus, information in male song can be used by females to discriminate the local population. The aviary data revealed that the rate of flight whistling correlated strongly with male courtship success. Thus, the vocal antecedents to mating in midwestern cowbirds include close‐range signaling to females followed by longer range signaling, perhaps to other males and to females other than the mate. Acoustic and behavioral differences between these two signals in diverse parts of the cowbirds' range suggest that the function of ‘speciestypical’ signals such as songs or whistles may not be fixed, a conclusion in keeping with the growing evidence of vocal and social mallcability in these brood parasitic birds.
Feeding behaviour of the greenbug Schizaphis graminum on wheat plants treated with imidacloprid and/or silicon
Authors: Costa R. R. , Moraes J. C. , DaCosta R. R. 
Published: May 2010

AbstractThe greenbug Schizaphis graminum (Rond.) (Hemiptera: Aphididae) is one of the principal pests of Triticum aestivum L. and may be responsible for the injection of toxins, the transmission of viral infections and, ultimately, plant death. The aphid can be controlled by the use of selective insecticides or with the application of silicon. The objective of the present study was to investigate the influence of imidacloprid and silicon on the feeding behaviour of S. graminum on wheat plants. Aphids collected from and reared on sorghum plants were maintained in a growth room at 25 ± 2°C; 12 h photoperiod. Seeds of the wheat cultivar EMBRAPA 22 were planted in plastic pots containing a commercially available soil substrate and thinned out 8 days after sowing to leave two vigorously growing seedlings in each pot. Four treatments (each replicated 25 times) were applied: (i) seeds were treated with imidacloprid (36 g/100 kg) 1 day prior to sowing; (ii) silicon (50 ml of 1% silicic acid; equivalent to a dose of 1000 kg of silicon/ha) was applied directly to the substrate 10 days after plant emergence; (iii) the described treatments with imidacloprid and silicon were applied jointly; and (iv) neither seeds nor substrate were treated (untreated controls). Electrical penetration graph assays were performed 15, 30 and 45 days after plant emergence. The results showed that wheat seed treatment with imidacloprid and/or the application of silicon to the substrate reduced both the feeding time of S. graminum and the percentage of insects that fed on phloem sap. Moreover, this study provides further support that the action of silicon may not be restricted to physical resistance (constitutive or induced) but may also involve induced plant chemical defence.
Reduction of major histocompatibility complex class I expression on bladder carcinoma following tumor antigen‐pulsed dendritic cell vaccine: Implications for immunoresistance in therapy
Authors: Li Mengqiang , Wang Huili , Xi Zhijun , Xu Enci , Jiang Xuejun , Chen Jiangying , Shi Wenzhen 
Published: May 2010

Objectives:  To clarify the relationship between a decreased major histocompatibility complex class I (MHC‐I) expression on bladder tumors and decreased immunological efficacy of tumor antigen‐pulsed dendritic cell vaccine in a rat bladder carcinoma model induced by N‐methyl‐N‐nitrosourea irrigation.Methods:  Enzyme‐linked immunosorbent assay was used to evaluate interferon‐gamma concentration in the serum and colorimetric lactate dehydrogenase release assay in vitro was used to test the cytotoxicity capability of T lymphocytes. MHC‐I expression on tumor cells was detected by flow cytometry and analyzed with CellQuest software.Results:  The tumor antigen sensitized dendritic cell vaccine group showed decreased hyperplastic formations, lower pathological stages in rat bladders and more potent cytotoxicity activity (P < 0.001) than the dendritic cell vaccine group. Additionally, immunization with pulsed dendritic cell vaccine induced higher specific cytokine production of interferon‐gamma. Nevertheless, a decreased MHC‐I expression on bladder tumors was tested after immunotherapy by pulsed dendritic cell vaccine on week 15. As expected, the cytotoxic activity of T lymphocytes from rats on tumor cells with low MHC‐I expression was also decreased to 19.70 ± 4.82% as compared with tumor cells with high MHC‐I (52.10 ± 8.66%, P = 0.005).Conclusions:  Tumor antigen sensitized dendritic cell vaccine has beneficial activity on N‐methyl‐N‐nitrosourea‐induced bladder cancer in situ in rats, but therapeutic responses are accompanied by decreased MHC‐I expression on tumors, possibly suggesting poor long‐term therapeutic outcomes.
Molecular complexity orchestrates modulation of phagosome biogenesis and escape to the cytosol of macrophages by Francisella tularensis
Authors: Asare Rexford , Abu Kwaik Yousef 
Published: May 2010

SummaryUpon entry of Francisella tularensis to macrophages, the Francisella‐containing phagosome (FCP) is trafficked into an acidified late endosome‐like phagosome with limited fusion to the lysosomes followed by rapid escape into the cytosol where the organism replicates. Although the Francisella Pathogenicity Island (FPI), which encodes a type VI‐like secretion apparatus, is required for modulation of phagosome biogenesis and escape into the cytosol, the mechanisms involved are not known. To decipher the molecular bases of modulation of biogenesis of the FCP and bacterial escape into the macrophage cytosol, we have screened a comprehensive mutant library of F. tularensis ssp. novicida for their defect in proliferation within human macrophages, followed by characterization of modulation of phagosome biogenesis and bacterial escape into the cytosol. Our data show that at least 202 genes are required for intracellular proliferation within macrophages. Among the 125 most defective mutants in intracellular proliferation, we show that the FCP of at least 91 mutants colocalize persistently with the late endosomal/lysosomal marker LAMP‐1 and fail to escape into the cytosol, as determined by fluorescence‐based phagosome integrity assays and transmission electron microscopy. At least 34 genes are required for proliferation within the cytosol but do not play a detectable role in modulation of phagosome biogenesis and bacterial escape into the cytosol. Our data indicate a tremendous adaptation and metabolic reprogramming by F. tularensis to adjust to the micro‐environmental and nutritional cues within the FCP, and these adjustments play essential roles in modulation of phagosome biogenesis and escape into the cytosol of macrophages as well as proliferation in the cytosol. The plethora of the networks of genes that orchestrate F. tularensis‐mediated modulation of phagosome biogenesis, phagosomal escape and bacterial proliferation within the cytosol is novel, complex and involves an unusually large portion of the genome of an intracellular pathogen.
Molecular bases of proliferation of Francisella tularensis in arthropod vectors
Authors: Asare Rexford , Akimana Christine , Jones Snake , Abu Kwaik Yousef 
Published: May 2010

SummaryArthropod vectors are important vehicles for transmission of Francisella tularensis between mammals, but very little is known about the F. tularensis–arthropod vector interaction. Drosophila melanogaster has been recently developed as an arthropod vector model for F. tularensis. We have shown that intracellular trafficking of F. tularensis within human monocytes‐derived macrophages and D. melanogaster‐derived S2 cells is very similar. Within both evolutionarily distant host cells, the Francisella‐containing phagosome matures to a late endosome‐like phagosome with limited fusion to lysosomes followed by rapid bacterial escape into the cytosol where the bacterial proliferate. To decipher the molecular bases of intracellular proliferation of F. tularensis within arthropod‐derived cells, we screened a comprehensive library of mutants of F. tularensis ssp. novicida for their defect in intracellular proliferation within D. melanogaster‐derived S2 cells. Our data show that 394 genes, representing 22% of the genome, are required for intracellular proliferation within D. melanogaster‐derived S2 cells, including many of the Francisella Pathogenicity Island (FPI) genes that are also required for proliferation within mammalian macrophages. Functional gene classes that exhibit growth defect include metabolic (25%), FPI (2%), type IV pili (1%), transport (16%) and DNA modification (5%). Among 168 most defective mutants in intracellular proliferation in S2 cells, 80 are defective in lethality and proliferation within adult D. melanogaster. The observation that only 135 of the 394 mutants that are defective in S2 cells are also defective in human macrophages indicates that F. tularensis utilize common as well as distinct mechanisms to proliferate within mammalian and arthropod cells. Our studies will facilitate deciphering the molecular aspects of F. tularensis–arthropod vector interaction and its patho‐adaptation to infect mammals.
The 3,4‐dihydroxyphenylacetic acid catabolon, a catabolic unit for degradation of biogenic amines tyramine and dopamine in Pseudomonas putida U
Authors: Arcos Mario , Olivera Elías R. , Arias Sagrario , Naharro Germán , Luengo José M. 
Published: May 2010

SummaryDegradation of tyramine and dopamine by Pseudomonas putida U involves the participation of twenty one proteins organized in two coupled catabolic pathways, Tyn (tynABFEC tynG tynR tynD, 12 338 bp) and Hpa (hpaR hpaBC hpaHI hpaX hpaG1G2EDF hpaA hpaY, 12 722 bp). The Tyn pathway catalyses the conversion of tyramine and dopamine into 4‐hydroxyphenylacetic acid (4HPA) and 3,4‐dihydroxyphenylacetic acid (3,4HPA) respectively. Together, the Tyn and Hpa pathways constitute a complex catabolic unit (the 3,4HPA catabolon) in which 3,4HPA is the central intermediate. The genes encoding Tyn proteins are organized in four consecutive transcriptional units (tynABFEC, tynG, tynR and tynD), whereas those encoding Hpa proteins constitute consecutive operons (hpaBC, hpaG1G2EDF, hpaX, hpaHI) and three independent units (hpaA, hpaR and hpaY). Genetic engineering approaches were used to clone tyn and hpa genes and then express them, either individually or in tandem, in plasmids and/or bacterial chromosomes, resulting in recombinant bacterial strains able to eliminate tyramine and dopamine from different media. These results enlarge our biochemical and genetic knowledge of the microbial catabolic routes involved in the degradation of aromatic bioamines. Furthermore, they provide potent biotechnological tools to be used in food processing and fermentation as well as new strategies that could be used for pharmacological and gene therapeutic applications in the near future.
The effect of group‐based lifestyle interventions on risk factors and insulin resistance in subjects at risk for metabolic syndrome: the Tabaruzaka Study 1
Authors: Yamashiro T. , Nishikawa T. , Isami S. , Wei C.‐N. , Fukumoto K. , Matsuo H. , Yoshinaga T. , Kukidome D. , Motoshima H. , Matsumura T. , Ueda A. , Araki E. 
Published: May 2010

Aim: The aim of this study was to evaluate the efficacy of two group‐based lifestyle interventions in ameliorating the risk factors of metabolic syndrome (MS) and insulin resistance. Methods: Ninety‐eight subjects who had at least one component of MS were randomized into standard intervention (SI) (4‐month intervention; n = 50) and extended intervention (EI) (10‐month intervention; n = 48) groups, and 39 subjects were followed up for a control group. The effects of intervention were evaluated after 10, 22 and 34 months. Results: At month 10, the standard and EI groups showed improved body mass index (BMI) (SI, −0.28; EI, −0.47; control, −0.09), high‐density lipoprotein (HDL) cholesterol, fasting plasma glucose and A1c and a decreased mean number of components of MS (SI, −0.37; EI, −0.51; control, 0.08). At month 34, the effects on BMI (SI, −0.66; EI, −0.60; control, −0.05) and HDL‐cholesterol were sustained for both the intervention groups. In controls, the increases in fasting plasma glucose and the mean number of components of MS from the baseline to month 34 were greater than those in the standard and EI groups. Whole body insulin sensitivity index and hepatic insulin resistance index were also improved at month 10. Conclusions: Group‐based lifestyle intervention could be an efficient way to prevent MS. Its effects were sustainable, at least in part, for 2 years. These effects may be mediated by an improvement in insulin sensitivity.
Phylogenetic relationships of the Suidae (Mammalia, Cetartiodactyla): new insights on the relationships within Suoidea
Authors: Orliac Maeva J. , Pierre‐Olivier Antoine , Ducrocq Stephane 
Published: May 2010

Orliac, M. J., Antoine, P. ‐O., Ducrocq, S. (2010). Phylogenetic relationships of the Suidae (Mammalia, Cetartiodactyla): new insights on the relationships within Suoidea. —Zoologica Scripta,39, 315–330.In most analyses, both molecular and morphological phylogenies of the Cetartiodactyla support the monophyly of Suoidea. However, the evolutionary history of this superfamily remains poorly known primarily due to long‐lasting debates about the taxonomic content and relationships of the suoid families and subfamilies. Despite their crucial position in the reconstruction of the phylogeny of Cetartiodactyla, Suoidea themselves have received little attention in those phylogenies, and no extensive analysis of the group has been performed so far. We therefore examine the phylogeny of the Suidae through the first phylogenetic analysis of Suoidea, including recent and fossil representatives of all four putative families. The results support the monophyly of the traditional suid subfamilies and indicate the Sanitheriidae as sister taxon to the Suidae clade. The evolutionary history within Suidae reveals its complexity, with major convergences involving important morphological structures such as the auditory region or the upper male canine. Divergent signals gathered from either dental or cranio‐mandibular features are responsible for two long‐lasting unresolved issues within Suoidea: the question of the relationships between ‘Old World’ and ‘New World’ peccaries remaining unsolved, as well as the position and familial status of the mid‐Tertiary tayassuidPerchoerus.
Management history and climate as key factors driving natterjack toad population trends in Britain
Authors: McGrath A. L. , Lorenzen K. 
Published: May 2010

AbstractAlong with other amphibian populations in Europe and elsewhere, natterjack toad Bufo calamita populations in Britain have declined since at least 1960. Conservation management since the 1970s has aimed to halt the decline and maintain viable populations at key sites throughout the species' recent historical range. Here, we assess population trends from 1985 to 2006 at 20 British B. calamita sites and evaluate the role of active management in maintaining good conservation status. We investigated the effects of 25 climatic, site‐characteristic and conservation management variables on population trends using general linear models. In single‐variable analyses, rainfall variables showed negative relationships with population trends. Among the site characteristics, being located at the very edge of the species' range (northern Irish Sea coast) and occurrence of common toad (B. bufo) were negatively related to B. calamita population trends. Management history (populations established via translocation as opposed to native populations) had a significant positive effect; as had sites that received greater translocation releases, undergone Species Recovery Programme management, and where common toad was absent. In multiple‐variable analyses, the combined effects of management history and average pre‐breeding season rainfall accounted for inter‐site variation in population trends. The rainfall effects in single‐ and multiple‐variable analyses were strongly influenced by three sites with very high rainfall whilst no clear effect was apparent for the remaining sites. This study highlights the role of climatic factors in population decline, and the importance of conservation management in stabilizing population trends. Climate change over the next 50–100 years is predicted to have limited impacts on most B. calamita populations in Britain, but strongly positive impacts on the most threatened populations located at the very edge of species' range that will benefit from reduced precipitation. A need for active conservation management will remain for the foreseeable future.
Sexual segregation and use of water by bighorn sheep: implications for conservation
Authors: Whiting J. C. , Bowyer R. T. , Flinders J. T. , Bleich V. C. , Kie J. G. 
Published: May 2010

AbstractMales and females of most dimorphic ruminants segregate outside the mating season, which may necessitate that conservation efforts focus on differential resources used by the sexes. Dimorphic bighorn sheep Ovis canadensis are one of the rarest ungulates in North America with some populations listed as endangered. Water sources are important for the persistence of populations of bighorns, especially in a changing climate. Understanding whether the sexes use different water sources could influence the conservation of this species and the habitats they occupy; however, little research exists regarding this important topic. We tested hypotheses relating to use of water sources by reintroduced male and female bighorns in Utah, USA. We investigated whether use of this resource differed across seasons by sex, and if sexes used water more during drought compared with non‐drought conditions. Bighorns used small, adjacent core areas during segregation, and males and females used different sources of water during that time. Males visited water sources used by females more during aggregation. Males and females used water sources more in summer, and males visited water sources more during rut than did females. Males and females did not use water sources more during drought compared with non‐drought conditions; however, sexes visited water sources more during the season following drought than following non‐drought conditions, indicating a time‐lag in use of this resource. Our results highlight the importance of water sources used by sexes of bighorns, and indicate that the existing criterion for distance of bighorn reintroductions from water may be inadequate for successful establishment of populations. We recommend conservationists assess availability of water sources near habitat used by male and female ungulates before conserving and manipulating habitat, siting artificial sources of water and reintroducing animals.
The Life‐history of Dromia vulgaris.
Authors: Lebour Marie V. 
Published: May 2010

Summary.We now have a good idea of the larval stages of Dromia vulgaris. It is evident from the above descriptions that the larvæ differ in almost every important point from those of the Brachyura, although the brachyuran larva has certain characters which may be derived from the Galatheidæ. Firstly, it differs in the armature of the pre‐zoea; afterwards, in the form of the carapace and spines of the zoea, antennule, antenna, in the presence of a functional swimming exopodite on the third maxillipede and in the number of setæ on the expodites of the maxillipedes, in the presence of a functional exopodite on the first leg and traces of exopodites on the second and third, in the shape and armature of the telson, and in the gills. On the other hand, it has certain features which resemble Upogebia and its relatives, particularly the antennal endopodite, the functional exopodite on the third maxillipede and the basal endopodite, the functional exopodite on the first leg, and the exopodites on legs 2 and 3. The telson also resembles that of the members of the Thalas‐sinidea except for the fact that there is no median spine. In the gills it differs much. In the armature of the pre‐zoea, the zoeal telson, carapace, functional third maxillipede, and basal endopodite, and in some other minor characters it resembles the Anomura, especially in the gills resembling the Galatheidea, but differs from the Anomura in having exopodites on the first three legs. Thus it combines characters belonging to the anomuran section of the Thalassinidea and to the Anomura. Dromia, however, with other members of the Dromiacea, has characters of its own, the antennal scale being surrounded with setæ which is unlike the Anomura and Thalassinidea, the third maxillipede being functional in the first zoea, the megalopa being spiny and shaped like the Brachyura, but the fifth legs unlike any brachyuran known, and the gills being quite different.It seems that we must remove the Dromiacea from the Brachyura, but, as Gurney rightly says, it is difficult to place it in the Anomura, and it cannot be placed in the Thalassinidea. Apparently the best position for it in a natural classification is in a separate group and not in the direct line of descent of the Brachyura. Possibly, again referring to Gurney, the Brachyura are derived from a stem common to the Galatheidea and Dromiace.Literature.