103 research outputs found
Dietary Supplementation with Yerba Mate (Ilex paraguariensis) Infusion Increases IRS-1 and PI3K mRNA Levels and Enhances Insulin Sensitivity and Secretion in Rat Pancreatic Islets
âYerba mateâ (YM), an aqueous extract of Ilex paraguariensis, has antioxidant, diuretic, cardio-protective and hypoglycaemic properties. Since its effect on the pancreatic islets remains unclear, we evaluated insulin sensitivity and glucose-stimulated insulin secretion (GSIS) in rats consuming YM or tap water (C) for 21 days. Glucose tolerance, glycemia, triglyceridemia, insulinemia, TBARS and FRAP serum levels were evaluated. GSIS and mRNA levels of insulin signaling pathway and inflammatory markers were measured in isolated pancreatic islets from both groups. In C rats, islets were incubated with YM extract or its phenolic components to measure GSIS. YM improved glucose tolerance, enhanced GSIS, increased FRAP plasma levels and islet mRNA levels of IRS-1 and PI3K (p110), and decreased TBARS plasma levels and islet gene expression of TNF-α and PAI-1. Islets from C rats incubated with 100 ”g/mL dry YM extract, 1 ”M chlorogenic acid, 0.1 and 1 ”M rutin, 1 ”M caffeic acid or 1 ”M quercetin showed an increase in GSIS. Our results suggest that YM enhances glucose tolerance because of its positive effects on GSIS, oxidative stress rate and insulin sensitivity in rat islets, suggesting that long-term dietary supplementation with YM may improve glucose homeostasis in pre-diabetes or type 2 diabetes
26Postoperative diagnosis and outcome in patients with revision arthroplasty for aseptic loosening
BACKGROUND:
The most common cause of implant failure is aseptic loosening (AL), followed by prosthetic joint infection (PJI). This study evaluates the incidence of PJI among patients operated with suspected AL and whether the diagnosis of PJI was predictive of subsequent implant failure including re-infection, at 2 years of follow up.
METHODS:
Patients undergoing revision hip or knee arthroplasty due to presumed AL from February 2009 to September 2011 were prospectively evaluated. A sonication fluid of prosthesis and tissue samples for microbiology and histopathology at the time of the surgery were collected. Implant failure include recurrent or persistent infection, reoperation for any reason or need for chronic antibiotic suppression.
RESULTS:
Of 198 patients with pre-and intraoperative diagnosis of AL, 24 (12.1 %) had postoperative diagnosis of PJI. After a follow up of 31 months (IQR: 21 to 38 months), 9 (37.5 %) of 24 patients in the PJI group had implant failure compared to only 1 (1.1 %) in the 198 of AL group (pâ20 CFU) and peri-prosthetic tissue culture were 87.5 % vs 66.7 %, respectively. Specificities were 100 % for both techniques (95 % CI, 97.9-100 %). A greater number of patients with PJI (79.1 %) had previous partial arthroplasty revisions than those patients in the AL group (56.9 %) (pâ=â0.04). In addition, 5 (55.5 %) patients with PJI and implant failure had more revision arthroplasties during the first year after the last implant placement than those patients with PJI without implant failure (1 patient; 6.7 %) (RR 3.8; 95 % CI 1.4-10.1; pâ=â0.015). On the other hand, 6 (25 %) patients finally diagnosed of PJI were initially diagnosed of AL in the first year after primary arthroplasty, whereas it was only 16 (9.2 %) patients in the group of true AL (RR 2.7; 95 % CI 1.2-6.1; pâ=â0.03).
CONCLUSIONS:
More than one tenth of patients with suspected AL are misdiagnosed PJI. Positive histology and positive peri-implant tissue and sonicate fluid cultures are highly predictive of implant failure in patients with PJI. Patients with greater number of partial hip revisions for a presumed AL had more risk of PJI. Early loosening is more often caused by hidden PJI than late loosening
Genetic variation and recombination of RdRp and HSP 70h genes of Citrus tristeza virus isolates from orange trees showing symptoms of citrus sudden death disease
<p>Abstract</p> <p>Background</p> <p>Citrus sudden death (CSD), a disease that rapidly kills orange trees, is an emerging threat to the Brazilian citrus industry. Although the causal agent of CSD has not been definitively determined, based on the disease's distribution and symptomatology it is suspected that the agent may be a new strain of <it>Citrus tristeza virus </it>(CTV). CTV genetic variation was therefore assessed in two Brazilian orange trees displaying CSD symptoms and a third with more conventional CTV symptoms.</p> <p>Results</p> <p>A total of 286 RNA-dependent-RNA polymerase (RdRp) and 284 heat shock protein 70 homolog (HSP70h) gene fragments were determined for CTV variants infecting the three trees. It was discovered that, despite differences in symptomatology, the trees were all apparently coinfected with similar populations of divergent CTV variants. While mixed CTV infections are common, the genetic distance between the most divergent population members observed (24.1% for RdRp and 11.0% for HSP70h) was far greater than that in previously described mixed infections. Recombinants of five distinct RdRp lineages and three distinct HSP70h lineages were easily detectable but respectively accounted for only 5.9 and 11.9% of the RdRp and HSP70h gene fragments analysed and there was no evidence of an association between particular recombinant mosaics and CSD. Also, comparisons of CTV population structures indicated that the two most similar CTV populations were those of one of the trees with CSD and the tree without CSD.</p> <p>Conclusion</p> <p>We suggest that if CTV is the causal agent of CSD, it is most likely a subtle feature of population structures within mixed infections and not merely the presence (or absence) of a single CTV variant within these populations that triggers the disease.</p
Molecular Characterization of Clinical Isolates of Aeromonas Species from Malaysia
Background: Aeromonas species are common inhabitants of aquatic environments giving rise to infections in both fish and humans. Identification of aeromonads to the species level is problematic and complex due to their phenotypic and genotypic heterogeneity. Methodology/Principal Findings: Aeromonas hydrophila or Aeromonas sp were genetically re-identified using a combination of previously published methods targeting GCAT, 16S rDNA and rpoD genes. Characterization based on the genus specific GCAT-PCR showed that 94 (96%) of the 98 strains belonged to the genus Aeromonas. Considering the patterns obtained for the 94 isolates with the 16S rDNA-RFLP identification method, 3 clusters were recognised, i.e. A. caviae (61%), A. hydrophila (17%) and an unknown group (22%) with atypical RFLP restriction patterns. However, the phylogenetic tree constructed with the obtained rpoD sequences showed that 47 strains (50%) clustered with the sequence of the type strain of A. aquariorum, 18 (19%) with A. caviae, 16 (17%) with A. hydrophila, 12 (13%) with A. veronii and one strain (1%) with the type strain of A. trota. PCR investigation revealed the presence of 10 virulence genes in the 94 isolates as: lip (91%), exu (87%), ela (86%), alt (79%), ser (77%), fla (74%), aer (72%), act (43%), aexT (24%) and ast (23%). Conclusions/Significance: This study emphasizes the importance of using more than one method for the correct identification of Aeromonas strains. The sequences of the rpoD gene enabled the unambiguous identication of the 9
Ecological implications of fine-scale fire patchiness and severity in tropical savannas of northern Australia
Research ArticleUnderstanding fine-scale fire patchiness
has significant implications for
ecological processes and biodiversity
conservation. It can affect local
extinction of and recolonisation by
relatively immobile fauna and poorly
seed-dispersed flora in fire-affected
areas. This study assesses fine-scale fire
patchiness and severity, and associated
implications for biodiversity, in north
Australian tropical savanna systems.
We used line transects to sample
burning patterns of ground layer
vegetation in different seasons and
vegetation structure types, within the
perimeter of 35 fires that occurred
between 2009 and 2011. We evaluated
two main fire characteristics: patchiness
(patch density and mean patch length)
and severity (inferred from char and
scorch heights, and char and ash
proportions). The mean burned area of ground vegetation was 83 % in the
early dry season (EDS: May to July)
and 93 % in the late dry season (LDS:
August to November). LDS fires were
less patchy (smaller and fewer
unburned patches), and had higher fire
severity (higher mean char and scorch
heights, and twice the proportion of
ash) than EDS fires. Fire patchiness
varied among vegetation types,
declining under more open canopy
structure. The relationship between
burned area and fire severity depended
on season, being strongly correlated in
the EDS and uncorrelated in the LDS.
Simulations performed to understand
the implications of patchiness on the
population dynamics of fire-interval
sensitive plant species showed that
small amounts of patchiness
substantially enhance survival. Our
results indicate that the ecological
impacts of high frequency fires on firesensitive
regional biodiversity
elements are likely to be lower than
has been predicted from remotely
sensed studies that are based on
assumptions of homogeneous burninginfo:eu-repo/semantics/publishedVersio
Maternal prepregnancy body mass index and offspring white matter microstructure: results from three birth cohorts
Prepregnancy maternal obesity is a global health problem and has been associated with offspring
metabolic and mental ill-health. However, there is a knowledge gap in understanding potential neurobiological factors
related to these associations. This study explored the relation between maternal prepregnancy body mass index (BMI) and
offspring brain white matter microstructure at the age of 6, 10, and 26 years in three independent cohorts. Maternal BMI was associated with higher FA and lower MD in multiple brain tracts in offspring aged 10 and
26 years, but not at 6 years of age. Future studies should examine whether our observations can be replicated and explore the
potential causal nature of the findings.This work was supported by the European
Unionâs Horizon 2020 research and innovation program [grant
agreement no. 633595 DynaHEALTH] and no. 733206 LifeCycle], the
Netherlands Organization for Health Research and Development
[ZONMW Vici project 016.VICI.170.200]. The PREOBE cohort was
funded by Spanish Ministry of Innovation and Science. Junta de
AndalucĂa: Excellence Projects (P06-CTS-02341) and Spanish Ministry of Economy and Competitiveness (BFU2012-40254-C03-01).
The first phase of the Generation R Study is made possible by financial
support from the Erasmus Medical Centre, the Erasmus University,
and the Netherlands Organization for Health Research and Development (ZonMW, grant ZonMW Geestkracht 10.000.1003). The
Northern Finland Birth Cohort 1986 is funded by University of Oulu,
University Hospital of Oulu, Academy of Finland (EGEA), Sigrid
Juselius Foundation, European Commission (EURO-BLCS, Framework 5 award QLG1-CT-2000-01643), NIH/NIMH
(5R01MH63706:02
Constraints on the structure and seasonal variations of Tritonâs atmosphere from the 5 October 2017 stellar occultation and previous observationsâ
Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range âŒ8 km to âŒ190 km, corresponding to pressure levels from 9 ÎŒbar down to a few nanobars. Results. (i) A pressure of 1.18 ± 0.03 ÎŒbar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 ÎŒbar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude
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