727 research outputs found
IFNAR1-Signalling Obstructs ICOS-mediated Humoral Immunity during Non-lethal Blood-Stage Plasmodium Infection
Funding: This work was funded by a Career Development Fellowship (1028634) and a project grant (GRNT1028641) awarded to AHa by the Australian National Health & Medical Research Council (NHMRC). IS was supported by The University of Queensland Centennial and IPRS Scholarships. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
Implementation of herd health program to improve survival of Boer goats in Malaysia.
A Boer goat breeding farm with 800 heads of breeder females, 50 breeder males, and 400 growing goats of various ages in Sabah, Malaysia was selected to study the effect of implementing herd health program. This included vaccination program against pneumonic mannheimiosis; fecal monitoring for helminthiasis, coccidiosis, and colibacillosis; and introduction of modified feeding regime comprised of day-time grazing and feeding of cut grass and supplemented feed. The herd health program was implemented in September 2007 and the impact was observed on body weight gains, body scoring, and annual mortality among adults and kids. It was found that implementation of herd health program significantly (p<0. 05) increased the average body weight gains in both adults and kids from 1. 8 g per kid and 0. 6 g per adult in 2006 to 3. 7 g per kid and 2. 2 g per adult in 2008. The percentage of adults with body scoring of <3 was significantly (p<0. 05) reduced from 82. 3% in 2006 to 77. 6% in 2007 and 4% in 2008. Similarly, the annual mortality rate was significantly (p<0. 05) reduced from 6. 5% among kids and 58. 2% among adults in 2006 to 12. 1% among kids and 10. 4% among adults in 2007, and to 9. 1% among kids and 1. 1% among adults in 2008. Therefore, it was concluded that implementation of herd health program significantly improved the survival and performance of goats
Are Nested Networks More Robust to Disturbance? A Test Using Epiphyte-Tree, Comensalistic Networks
Recent research on ecological networks suggests that mutualistic networks are
more nested than antagonistic ones and, as a result, they are more robust
against chains of extinctions caused by disturbances. We evaluate whether
mutualistic networks are more nested than comensalistic and antagonistic
networks, and whether highly nested, host-epiphyte comensalistic networks fit
the prediction of high robustness against disturbance. A review of 59 networks
including mutualistic, antagonistic and comensalistic relationships showed that
comensalistic networks are significantly more nested than antagonistic and
mutualistic networks, which did not differ between themselves. Epiphyte-host
networks from old-growth forests differed from those from disturbed forest in
several topological parameters based on both qualitative and quantitative
matrices. Network robustness increased with network size, but the slope of this
relationship varied with nestedness and connectance. Our results indicate that
interaction networks show complex responses to disturbances, which influence
their topology and indirectly affect their robustness against species
extinctions
A transcriptomic snapshot of early molecular communication between Pasteuria penetrans and Meloidogyne incognita
© The Author(s). 2018Background: Southern root-knot nematode Meloidogyne incognita (Kofoid and White, 1919), Chitwood, 1949 is a key pest of agricultural crops. Pasteuria penetrans is a hyperparasitic bacterium capable of suppressing the nematode reproduction, and represents a typical coevolved pathogen-hyperparasite system. Attachment of Pasteuria endospores to the cuticle of second-stage nematode juveniles is the first and pivotal step in the bacterial infection. RNA-Seq was used to understand the early transcriptional response of the root-knot nematode at 8 h post Pasteuria endospore attachment. Results: A total of 52,485 transcripts were assembled from the high quality (HQ) reads, out of which 582 transcripts were found differentially expressed in the Pasteuria endospore encumbered J2 s, of which 229 were up-regulated and 353 were down-regulated. Pasteuria infection caused a suppression of the protein synthesis machinery of the nematode. Several of the differentially expressed transcripts were putatively involved in nematode innate immunity, signaling, stress responses, endospore attachment process and post-attachment behavioral modification of the juveniles. The expression profiles of fifteen selected transcripts were validated to be true by the qRT PCR. RNAi based silencing of transcripts coding for fructose bisphosphate aldolase and glucosyl transferase caused a reduction in endospore attachment as compared to the controls, whereas, silencing of aspartic protease and ubiquitin coding transcripts resulted in higher incidence of endospore attachment on the nematode cuticle. Conclusions: Here we provide evidence of an early transcriptional response by the nematode upon infection by Pasteuria prior to root invasion. We found that adhesion of Pasteuria endospores to the cuticle induced a down-regulated protein response in the nematode. In addition, we show that fructose bisphosphate aldolase, glucosyl transferase, aspartic protease and ubiquitin coding transcripts are involved in modulating the endospore attachment on the nematode cuticle. Our results add new and significant information to the existing knowledge on early molecular interaction between M. incognita and P. penetrans.Peer reviewedFinal Published versio
Steroid receptor expression in the fish inner ear varies with sex, social status, and reproductive state
<p>Abstract</p> <p>Background</p> <p>Gonadal and stress-related steroid hormones are known to influence auditory function across vertebrates but the cellular and molecular mechanisms responsible for steroid-mediated auditory plasticity at the level of the inner ear remain unknown. The presence of steroid receptors in the ear suggests a direct pathway for hormones to act on the peripheral auditory system, but little is known about which receptors are expressed in the ear or whether their expression levels change with internal physiological state or external social cues. We used qRT-PCR to measure mRNA expression levels of multiple steroid receptor subtypes (estrogen receptors: ERα, ERβa, ERβb; androgen receptors: ARα, ARβ; corticosteroid receptors: GR2, GR1a/b, MR) and aromatase in the main hearing organ of the inner ear (saccule) in the highly social African cichlid fish <it>Astatotilapia burtoni</it>, and tested whether these receptor levels were correlated with circulating steroid concentrations.</p> <p>Results</p> <p>We show that multiple steroid receptor subtypes are expressed within the main hearing organ of a single vertebrate species, and that expression levels differ between the sexes. We also show that steroid receptor subtype-specific changes in mRNA expression are associated with reproductive phase in females and social status in males. Sex-steroid receptor mRNA levels were negatively correlated with circulating estradiol and androgens in both males and females, suggesting possible ligand down-regulation of receptors in the inner ear. In contrast, saccular changes in corticosteroid receptor mRNA levels were not related to serum cortisol levels. Circulating steroid levels and receptor subtype mRNA levels were not as tightly correlated in males as compared to females, suggesting different regulatory mechanisms between sexes.</p> <p>Conclusions</p> <p>This is the most comprehensive study of sex-, social-, and reproductive-related steroid receptor mRNA expression in the peripheral auditory system of any single vertebrate. Our data suggest that changes in steroid receptor mRNA expression in the inner ear could be a regulatory mechanism for physiological state-dependent auditory plasticity across vertebrates.</p
ABI3 ectopic expression reduces in vitro and in vivo cell growth properties while inducing senescence
<p>Abstract</p> <p>Background</p> <p>Mounting evidence has indicated that <it>ABI3 </it>(ABI family member 3) function as a tumor suppressor gene, although the molecular mechanism by which ABI3 acts remains largely unknown.</p> <p>Methods</p> <p>The present study investigated <it>ABI3 </it>expression in a large panel of benign and malignant thyroid tumors and explored a correlation between the expression of ABI3 and its potential partner ABI3-binding protein (ABI3BP). We next explored the biological effects of <it>ABI3 </it>ectopic expression in thyroid and colon carcinoma cell lines, in which its expression was reduced or absent.</p> <p>Results</p> <p>We not only observed that <it>ABI3 </it>expression is reduced or lost in most carcinomas but also that there is a positive correlation between <it>ABI3 </it>and <it>ABI3BP </it>expression. Ectopic expression of <it>ABI3 </it>was sufficient to lead to a lower transforming activity, reduced tumor <it>in vitro </it>growth properties, suppressed <it>in vitro </it>anchorage-independent growth and <it>in vivo </it>tumor formation while, cellular senescence increased. These responses were accompanied by the up-regulation of the cell cycle inhibitor <it>p21 </it><sup>WAF1 </sup>and reduced ERK phosphorylation and <it>E2F1 </it>expression.</p> <p>Conclusions</p> <p>Our result links <it>ABI3 </it>to the pathogenesis and progression of some cancers and suggests that ABI3 or its pathway might have interest as therapeutic target. These results also suggest that the pathways through which <it>ABI3 </it>works should be further characterized.</p
Phospholipids Trigger Cryptococcus neoformans Capsular Enlargement during Interactions with Amoebae and Macrophages
A remarkable aspect of the interaction of Cryptococcus
neoformans with mammalian hosts is a consistent increase in capsule
volume. Given that many aspects of the interaction of C.
neoformans with macrophages are also observed with amoebae, we
hypothesized that the capsule enlargement phenomenon also had a protozoan
parallel. Incubation of C. neoformans with Acanthamoeba
castellanii resulted in C. neoformans capsular
enlargement. The phenomenon required contact between fungal and protozoan cells
but did not require amoeba viability. Analysis of amoebae extracts showed that
the likely stimuli for capsule enlargement were protozoan polar lipids. Extracts
from macrophages and mammalian serum also triggered cryptococcal capsular
enlargement. C. neoformans capsule enlargement required
expression of fungal phospholipase B, but not phospholipase C. Purified
phospholipids, in particular, phosphatidylcholine, and derived molecules
triggered capsular enlargement with the subsequent formation of giant cells.
These results implicate phospholipids as a trigger for both C.
neoformans capsule enlargement in vivo and
exopolysaccharide production. The observation that the incubation of C.
neoformans with phospholipids led to the formation of giant cells
provides the means to generate these enigmatic cells in vitro.
Protozoan- or mammalian-derived polar lipids could represent a danger signal for
C. neoformans that triggers capsular enlargement as a
non-specific defense mechanism against potential predatory cells. Hence,
phospholipids are the first host-derived molecules identified to trigger
capsular enlargement. The parallels apparent in the capsular response of
C. neoformans to both amoebae and macrophages provide
additional support for the notion that certain aspects of cryptococcal virulence
emerged as a consequence of environmental interactions with other microorganisms
such as protists
Study of decays to the final state and evidence for the decay
A study of decays is performed for the first time
using data corresponding to an integrated luminosity of 3.0
collected by the LHCb experiment in collisions at centre-of-mass energies
of and TeV. Evidence for the decay
is reported with a significance of 4.0 standard deviations, resulting in the
measurement of
to
be .
Here denotes a branching fraction while and
are the production cross-sections for and mesons.
An indication of weak annihilation is found for the region
, with a significance of
2.4 standard deviations.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-022.html,
link to supplemental material inserted in the reference
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