The influence of acetylsalicylic acid on oxylipin migration in Cryptococcus neoformans var. neoformans UOFS Y-1378

In this paper we report the influence of acetylsalicylic acid on oxylipin migration in Cryptococcus neoformans var. neoformans UOFS Y-1378, previously isolated from human bone lesion. Transmission electron microscopy suggests that osmiophilic material originates in mitochondria and is deposited inside the yeast cell wall, from which it is excreted into the environment, along capsule protuberances, or through capsule detachments. Previous studies using immunogold labeling indicate that these osmiophilic layers contain 3-hydroxy oxylipins. In this study, the addition of acetylsalicylic acid (an inhibitor of mitochondrial function) in increasing amounts to the cells abrogated the migration of osmiophilic material, as well as capsule detachment from cell walls, and hence, oxylipin excretion. Consequently, we hypothesize that 3-hydroxy oxylipins are produced in mitochondria, probably via incomplete beta-oxidation or fatty acid synthesis, from which they are deposited inside the cell wall and excreted through tubular protuberances attached to the surrounding capsules and (or) through detachment of these oxylipin-containing capsules.     

In vivo expression of Toll-like receptor 2 and 4 by renal epithelial cells: IFN-gamma and TNF-alpha mediated up-regulation during inflammation.

The reported requirement of functional Toll-like receptor (TLR)4 for resistance to Gram-negative pyelonephritis prompted us to localize the expression of TLR2 and TLR4 mRNA in the kidney at the cellular level by in situ hybridization. The majority of the constitutive TLR2 and TLR4 mRNA expression was found to be strategically located in the renal epithelial cells. Assuming that the TLR mRNA expression is representative of apical protein expression, this suggests that these cells are able to detect and react with bacteria present in the lumen of the tubules. To gain insight in the regulation of TLR expression during inflammation, we used a model for renal inflammation. Renal inflammation evoked by ischemia markedly enhanced synthesis of TLR2 and TLR4 mRNA in the distal tubular epithelium, the thin limb of Henle's loop, and collecting ducts. The increased renal TLR4 mRNA expression was associated with significant elevation of renal TLR4 protein expression as evaluated by Western blotting. Using RT-PCR, the enhanced TLR2 and TLR4 mRNA expression was shown to be completely dependent on the action of IFN-gamma and TNF-alpha. These results indicate a potential mechanism of increased immunosurveillance during inflammation at the site in which ascending bacteria enter the kidney tissue, i.e., the collecting ducts and the distal part of the nephron.     

Investigating movement in the laboratory: dispersal apparatus designs and the red flour beetle,Tribolium castaneum

The natural dispersal of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) has been emulated in the laboratory for more than 50 years, using a simple dispersal apparatus. This has typically comprised of a starting container (initial resource or patch) connected by tubing, which contains thread for the animals to climb into a tube and hence to an end container. That is, beetles move to a new viable resource or patch from an inter‐patch zone or non‐viable habitat. We modified this basic apparatus design to test the effect of tubing length and tubing insertion angle on the dispersal rate and proportion of successful dispersers. We expected that the proportion of successful dispersers would be repeatable within each apparatus design, and that increasing tubing length and steepness of the insertion angle would reduce dispersal rate and success across apparatus designs. Dispersal increased linearly through time, similarly so for both males and females. The design with the most vertical tubing insertion angle had a lower proportion of successful dispersers. Tubing length also had a negative relationship with dispersal success (as judged by insects reaching the end container), but a significant reduction in dispersal success was only apparent between the shortest and longest tubing between containers. We suggest that locating and climbing the vertical section of string before they can enter the tubing between containers restricts dispersal and that at higher densities, insects exhibit greater inclination to climb. This type of apparatus has flexible design tolerances and further potential to study the dispersal of other small insect species that primarily use pedestrian locomotion.     

Responses of a wetland ecosystem to the controlled introduction of invasive fish

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Temperature effects on forest understorey plants in hedgerows: a combined warming and transplant experiment

Background and AimsHedgerows have been shown to improve forest connectivity, leading to an increased probability of species tracking the shifting bioclimatic envelopes. However, it is still unknown how species in hedgerows respond to temperature changes, and whether effects differ compared with those in nearby forests. We aimed to elucidate how ongoing changes in the climate system will affect the efficiency of hedgerows in supporting forest plant persistence and migration in agricultural landscapes.MethodsHere we report results from the first warming experiment in hedgerows. We combined reciprocal transplantation of plants along an 860-km latitudinal transect with experimental warming to assess the effects of temperature on vegetative growth and reproduction of two common forest herbs (Anemone nemorosa and Geum urbanum) in hedgerows versus forests.Key ResultsBoth species grew taller and produced more biomass in forests than in hedgerows, most likely due to higher competition with ruderals and graminoids in hedgerows. Adult plant performance of both species generally benefitted from experimental warming, despite lower survival of A. nemorosa in heated plots. Transplantation affected the species differently: A. nemorosa plants grew taller, produced more biomass and showed higher survival when transplanted at their home site, indicating local adaptation, while individuals of G. urbanum showed greater height, biomass, reproductive output and survival when transplanted northwards, likely owing to the higher light availability associated with increasing photoperiod during the growing season.ConclusionsThese findings demonstrate that some forest herbs can show phenotypic plasticity to warming temperatures, potentially increasing their ability to benefit from hedgerows as ecological corridors. Our study thus provides novel insights into the impacts of climate change on understorey plant community dynamics in hedgerows, and how rising temperature can influence the efficiency of these corridors to assist forest species’ persistence and colonization within and beyond their current distribution range.     

Pulmonary function,exhaled nitric oxide and symptoms in asthma patients with obesity: a cross-sectional study

Background

Obesity is a risk factor for the development of asthma. In patients with obesity the diagnosis of asthma is often based on symptoms, but without objective measurements. Nevertheless, obesity-associated asthma is recognized as a distinct asthma phenotype. Therefore, this study explores lung function and symptoms in asthma patients with and without obesity.

Methods

The Netherlands Epidemiology of Obesity (NEO) study is a population-based cohort study with 6671 participants (aged 45–65 years) of whom 472 had asthma. Of this latter group, linear regression analysis was used to examine differences in lung function and symptoms between asthma patients with (n?=?248) and without obesity (n?=?224), and between asthma patients with and without increased Fe_NO. Analyses were adjusted for confounders.

Results

Asthma patients with obesity had lower predicted FEV₁ and FVC values than patients without obesity [adjusted mean difference (MD) -3.3% predicted, 95% CI -6.5, ?0.2; adjusted MD ?5.0% predicted, 95% CI -7.8, ?2.1]. The prevalence of symptoms was higher in patients with obesity. Asthma patients with obesity and with increased Fe_NO had lower FEV₁ and FEV₁/FVC values compared with those with low Fe_NO (adjusted MD ?6.9% predicted, 95% CI -11.7, ?2.0; ?2.4%, 95% CI -4.6, ?0.2).

Conclusion

Asthma patients with obesity had lower FEV₁ and FVC values than patients without obesity. This suggests that patients with obesity have restrictive lung function changes, rather than obstructive changes. Asthma patients with obesity and increased Fe_NO showed more obstructive changes. Fe_NO might help to identify patients with eosinophilic inflammation-driven asthma, whereas patients with low Fe_NO might have an obesity-associated asthma phenotype in which symptoms are partly caused by the obesity.

     

Low flow extracorporeal CO<Subscript>2</Subscript> removal in ARDS patients: a prospective short-term crossover pilot study

Background

Lung protective mechanical ventilation (MV) is the corner stone of therapy for ARDS. However, its use may be limited by respiratory acidosis.This study explored feasibility of, effectiveness and safety of low flow extracorporeal CO₂ removal (ECCO₂R).

Methods

This was a prospective pilot study, using the Abylcap® (Bellco) ECCO₂R, with crossover off-on-off design (2-h blocks) under stable MV settings, and follow up till end of ECCO₂R. Primary endpoint for effectiveness was a 20% reduction of PaCO₂ after the first 2-h. Adverse events (AE) were recorded prospectively.We included 10 ARDS patients on MV, with PaO₂/FiO₂?<?150 mmHg, tidal volume?≤?8 mL/kg with positive end-expiratory pressure ≥?5 cmH₂O, FiO₂ titrated to SaO₂ 88–95%, plateau pressure ≥?28 cmH₂O, and respiratory acidosis (pH <7.25).

Results

After 2-h of ECCO₂R, 6 patients had a ≥?20% decrease in PaCO₂ (60%); PaCO₂ decreased 28.4% (from 58.4 to 48.7 mmHg, p?=?0.005), and pH increased (1.59%, p?=?0.005). ECCO₂R was hemodynamically well tolerated. During the whole period of ECCO₂R, 6 patients had an AE (60%); bleeding occurred in 5 patients (50%) and circuit thrombosis in 3 patients (30%), these were judged not to be life threatening.

Conclusions

In ARDS patients, low flow ECCO₂R significantly reduced PaCO₂ after 2 h, Follow up during the entire ECCO₂R period revealed a high incidence of bleeding and circuit thrombosis.

Trial registration

https://clinicaltrials.gov identifier: NCT01911533, registered 23 July 2013.