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61.
Jane Alisa Allardyce James Edward Rookes Hashmath Inayath Hussain David Miles Cahill 《Functional & integrative genomics》2013,13(2):217-228
Phytophthora cinnamomi is a soil-borne plant pathogen that has caused widespread damage to vulnerable native ecosystems and agriculture systems across the world and shows no sign of abating. Management of the pathogen in the natural environment is difficult and the options are limited. In order to discover more about how resistant plants are able to defend themselves against this generalist pathogen, a microarray study of plant gene expression following root inoculation with P. cinnamomi was undertaken. Zea mays was used as a resistant model plant, and microarray analysis was conducted using the Affymetrix GeneChip Maize Genome Array on root samples collected at 6- and 24-h post-inoculation. Over 300 genes were differentially expressed in inoculated roots compared with controls across the two time points. Following Gene Ontology enrichment analysis and REVIGO visualisation of the up-regulated genes, many were implicated in plant defence responses to biotic stress. Genes that were up-regulated included those involved in phytoalexin biosynthesis and jasmonic acid/ethylene biosynthesis and other defence-related genes including those encoding glutathione S-transferases and serine-protease inhibitors. Of particular interest was the identification of the two most highly up-regulated genes, terpene synthase11 (Tps11) and kaurene synthase2 (An2), which are both involved in production of terpenoid phytoalexins. This is the first study that has investigated gene expression at a global level in roots in response to P. cinnamomi in a model plant species and provides valuable insights into the mechanisms involved in defence. 相似文献
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64.
Katrin Kuhls Elisa Cupolillo Soraia O. Silva Carola Schweynoch Mariana C?rtes Boité Maria N. Mello Isabel Mauricio Michael Miles Thierry Wirth Gabriele Sch?nian 《PLoS neglected tropical diseases》2013,7(10)
Background/Objectives: Parasites of the subgenus Leishmania (Viannia) cause varying clinical symptoms ranging from cutaneous leishmaniases (CL) with single or few lesions, disseminated CL (DL) with multiple lesions to disfiguring forms of mucocutaneous leishmaniasis (MCL). In this population genetics study, 37 strains of L. (V.) guyanensis, 63 of L. (V.) braziliensis, four of L. (V.) shawi, six of L. (V.) lainsoni, seven of L. (V.) naiffi, one each of L. (V.) utingensis and L. (V.) lindenbergi, and one L. (V.) lainsoni/L. naiffi hybrid from different endemic foci in Brazil were examined for variation at 15 hyper-variable microsatellite markers.
Methodology/Principal findings: The multilocus microsatellite profiles obtained for the 120 strains were analysed using both model- and distance-based methods. Significant genetic diversity was observed for all L. (Viannia) strains studied. The two cluster analysis approaches identified two principal genetic groups or populations, one consisting of strains of L. (V.) guyanensis from the Amazon region and the other of strains of L. (V.) braziliensis isolated along the Atlantic coast of Brazil. A third group comprised a heterogeneous assembly of species, including other strains of L. braziliensis isolated from the north of Brazil, which were extremely polymorphic. The latter strains seemed to be more closely related to those of L. (V.) shawi, L. (V.) naiffi, and L. (V.) lainsoni, also isolated in northern Brazilian foci. The MLMT approach identified an epidemic clone consisting of 13 strains of L. braziliensis from Minas Gerais, but evidence for recombination was obtained for the populations of L. (V.) braziliensis from the Atlantic coast and for L. (V.) guyanensis.
Conclusions/Significance: Different levels of recombination versus clonality seem to occur within the subgenus L. (Viannia). Though clearly departing from panmixia, sporadic, but long-term sustained recombination might explain the tremendous genetic diversity and limited population structure found for such L. (Viannia) strains. 相似文献
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Kathryn L. Gatford Siti A. Sulaiman Saidatul N. B. Mohammad Miles J. De Blasio M. Lyn Harland Rebecca A. Simmons Julie A. Owens 《PloS one》2013,8(2)
Background
IUGR increases the risk of type 2 diabetes mellitus (T2DM) in later life, due to reduced insulin sensitivity and impaired adaptation of insulin secretion. In IUGR rats, development of T2DM can be prevented by neonatal administration of the GLP-1 analogue exendin-4. We therefore investigated effects of neonatal exendin-4 administration on insulin action and β-cell mass and function in the IUGR neonate in the sheep, a species with a more developed pancreas at birth.Methods
Twin IUGR lambs were injected s.c. daily with vehicle (IUGR+Veh, n = 8) or exendin-4 (1 nmol.kg-1, IUGR+Ex-4, n = 8), and singleton control lambs were injected with vehicle (CON, n = 7), from d 1 to 16 of age. Glucose-stimulated insulin secretion and insulin sensitivity were measured in vivo during treatment (d 12–14). Body composition, β-cell mass and in vitro insulin secretion of isolated pancreatic islets were measured at d 16.Principal Findings
IUGR+Veh did not alter in vivo insulin secretion or insulin sensitivity or β-cell mass, but increased glucose-stimulated insulin secretion in vitro. Exendin-4 treatment of the IUGR lamb impaired glucose tolerance in vivo, reflecting reduced insulin sensitivity, and normalised glucose-stimulated insulin secretion in vitro. Exendin-4 also reduced neonatal growth and visceral fat accumulation in IUGR lambs, known risk factors for later T2DM.Conclusions
Neonatal exendin-4 induces changes in IUGR lambs that might improve later insulin action. Whether these effects of exendin-4 lead to improved insulin action in adult life after IUGR in the sheep, as in the PR rat, requires further investigation. 相似文献67.
Chihiro Motozono John J. Miles Zafrul Hasan Hiroyuki Gatanaga Stanley C. Meribe David A. Price Shinichi Oka Andrew K. Sewell Takamasa Ueno 《PloS one》2013,8(6)
Antigen cross-reactivity is an inbuilt feature of the T cell compartment. However, little is known about the flexibility of T cell recognition in the context of genetically variable pathogens such as HIV-1. In this study, we used a combinatorial library containing 24 billion octamer peptides to characterize the cross-reactivity profiles of CD8+ T cells specific for the immunodominant HIV-1 subtype B Nef epitope VY8 (VPLRPMTY) presented by HLA-B*35∶01. In conjunction, we examined naturally occurring antigenic variations within the VY8 epitope. Sequence analysis of plasma viral RNA isolated from 336 HIV-1-infected individuals revealed variability at position (P) 3 and P8 of VY8; Phe at P8, but not Val at P3, was identified as an HLA-B*35∶01-associated polymorphism. VY8-specific T cells generated from several different HIV-1-infected patients showed unique and clonotype-dependent cross-reactivity footprints. Nonetheless, all T cells recognized both the index Leu and mutant Val at P3 equally well. In contrast, competitive titration assays revealed that the Tyr to Phe substitution at P8 reduced T cell recognition by 50–130 fold despite intact peptide binding to HLA-B*35∶01. These findings explain the preferential selection of Phe at the C-terminus of VY8 in HLA-B*35∶01+ individuals and demonstrate that HIV-1 can exploit the limitations of T cell recognition in vivo. 相似文献
68.
Miles J. Penfold Martin L. Schulman Sarah Clift Lisa du Plessis Peter N. Thompson Marthinus J. Hartman 《Zoo biology》2020,39(5):325-333
The histological effect on the felid uterus of sterilization, via ovariectomy or salpingectomy, is currently unknown. To investigate the association of ovariectomy or salpingectomy with uterine health, it is first necessary to establish if changes are distributed evenly throughout the uterus. Both laparoscopic ovariectomy and salpingectomy with concurrent sampling of the tip of the uterine horn are possible in the cheetah. Currently accepted practice for histopathological screening of the uterus utilizes four biopsy samples. It is not known whether this method accurately reflects the status of the entire uterus. In this study we histologically examined the uteri of six older cheetahs (one 7-year-old and five 10–10.5-year-old animals) via 21 tissue samples (three samples from seven different anatomical regions) per cheetah to determine overall uterine health. Although no defined lesions were detected, mild endometrial gland dilation, assumed to be of no functional consequence, was observed in multiple samples. The odds of observing this dilation was lowest in the uterine body and progressively increased in a cranial direction, being significantly higher at the tip of the uterine horns (OR = 11.5; 95% CI, 2.0-65.1; p = 0.006). This supported the reliability of sampling the tip of the uterine horn to screen for endometrial gland dilation. 相似文献
69.
The effects of ocean acidification will be pronounced in high-latitude marine communities, although little is known on how reproduction in free-spawning polar invertebrates will respond. Using the circum-Antarctic sea star Odontaster validus, we examined fertilisation, larval survival and development under a controlled seawater treatment (temperature = ?0.5 °C, pH 8.1, pCO2(aq) = 326.6 μatm, TA = 2,274.2 μmol kg soln?1), two near-future pH treatments (pH 7.8 and 7.6) and an extreme treatment (pH 7.0). At a sperm concentration of 3.5 × 105 sperm ml?1, percentage of fertilisation was 98–90 % across a pH 8.1–7.0 range. At near-future pH ranges (pH 7.8 and 7.6), fertilisation was not significantly lower than in the control pH 8.1 except at the lowest sperm concentration (2.2 × 103 sperm ml?1) where fertilisation was reduced to 60 and 61 % in pH 7.6 and 7.8, respectively. Larval survival was not significantly affected by a decrease in pH of 0.3 units, but at pH 7.6 survival was significantly reduced. This difference was apparent at 9 days, and at the end of the experiment at 58 days, survival was 55 % compared with 85 % in the ambient treatment. Near-future changes to pH yielded smaller larvae, a result of both subtle differences in their morphology and slowed development rates, while larvae at pH 7.0 showed evidence of abnormal development. O. validus fertilisation and larval success declines in seawater pH conditions expected in coastal Antarctica over the coming decades, although the responses observed are within the range observed in warmer-water echinoderms. 相似文献
70.
Pierre L. van den Berghe Walker Connor A. H. M. Kirk‐Greene Robert Mahuta Robert Miles John Beattie 《Ethnic and racial studies》2013,36(4):484-498
Milton M. Gordon, HUMAN NATURE, CLASS AND ETHNICITY. London and New York, Oxford University Press, 1978, 302 pp., £6.50, $11.95 ($3.50 paper). June Teufel Dreyer, CHINA'S FORTY MILLIONS: MINORITY NATIONALITIES AND NATIONAL INTEGRATION IN THE PEOPLE'S REPUBLIC OF CHINA. Cambridge (Mass.) and London, Harvard University Press, 1976, 333 pp., £9.55. W. Stanford Reid (ed), THE SCOTTISH TRADITION IN CANADA. Toronto, McClelland & Stewart, 1976, xi + 324 pp., $12.55. I. H. Kawharu, MAORI LAND TENURE: STUDIES OF A CHANGING INSTITUTION. Oxford, Clarendon Press, 1977, 362 pp., £13.50. David T. Wellman, PORTRAITS OF WHITE RACISM. London, Cambridge University Press, 1977, 254 pp., £9.50 (£4.00 paper). Lucy Mair, AFRICAN KINGDOMS. Oxford, Clarendon Press, 1977, 151 pp., £3.95, (£1.95 paper). Roger Scott, NORTHERN IRELAND: THE POLITICS OF VIOLENCE. Canberra Series in Administrative Studies 2., Canberra College of Advanced Education, 1977, 84 pp., n.p. James A. Geschwender, CLASS, RACE AND WORKER INSURGENCY: THE LEAGUE OF BLACK REVOLUTIONARY WORKERS. London, Cambridge University Press, 1977, 249 pp., £8.50 (£3.50 paper). Crawford Young, THE POLITICS OF CULTURAL PLURALISM. Madison, University of Wisconsin Press, 1976. 560 pp., £13.60. D. C. R. A. Goonetilleke, DEVELOPING COUNTRIES IN BRITISH FICTION. London, Macmillan, 1977, 282 pp., £8.95. M. M. Mahood, THE COLONIAL ENCOUNTER. London, Rex Collings, 1977, 210 pp., £4.75. Brian V. Street, THE SAVAGE IN LITERATURE. London, Routledge & Kegan Paul, 1975, 207 pp., £5.75. 相似文献