Aging aggravates ischemic stroke‐induced brain damage in mice with chronic peripheral infection

Ischemic stroke is confounded by conditions such as atherosclerosis, diabetes, and infection, all of which alter peripheral inflammatory processes with concomitant impact on stroke outcome. The majority of the stroke patients are elderly, but the impact of interactions between aging and inflammation on stroke remains unknown. We thus investigated the influence of age on the outcome of stroke in animals predisposed to systemic chronic infection. Th1‐polarized chronic systemic infection was induced in 18–22 month and 4‐month‐old C57BL/6j mice by administration of Trichuris muris (gut parasite). One month after infection, mice underwent permanent middle cerebral artery occlusion and infarct size, brain gliosis, and brain and plasma cytokine profiles were analyzed. Chronic infection increased the infarct size in aged but not in young mice at 24 h. Aged, ischemic mice showed altered plasma and brain cytokine responses, while the lesion size correlated with plasma prestroke levels of RANTES. Moreover, the old, infected mice exhibited significantly increased neutrophil recruitment and upregulation of both plasma interleukin‐17α and tumor necrosis factor‐α levels. Neither age nor infection status alone or in combination altered the ischemia‐induced brain microgliosis. Our results show that chronic peripheral infection in aged animals renders the brain more vulnerable to ischemic insults, possibly by increasing the invasion of neutrophils and altering the inflammation status in the blood and brain. Understanding the interactions between age and infections is crucial for developing a better therapeutic regimen for ischemic stroke and when modeling it as a disease of the elderly.     

Role of ultrasonography in diagnosing early rheumatoid arthritis and remission of rheumatoid arthritis - a systematic review of the literature

Introduction

Ultrasonography (US) might have an added value to clinical examination in diagnosing early rheumatoid arthritis (RA) and assessing remission of RA. We aimed to clarify the added value of US in RA in these situations performing a systematic review.

Methods

A systematic literature search was performed for RA, US, diagnosis and remission. Methodological quality was assessed; the wide variability in the design of studies prohibited pooling of results.

Results

Six papers on the added value of US diagnosing early RA were found, in which at least bilateral metacarpophalangeal (MCP), wrists and metatarsophalangeal (MTP) joints were scanned. Compared to clinical examination, US was superior with regard to detecting synovitis and predicting progression to persistent arthritis or RA. Eleven papers on assessing remission were identified, in which at least the wrist and the MCP joints of the dominant hand were scanned. Often US detected inflammation in patients clinically in remission, irrespective of the remission criteria used. Power Doppler signs of synovitis predicted X-ray progression and future flare in patients clinically in remission.

Conclusions

US appears to have added value to clinical examination for diagnosing of RA when scanning at least MCP, wrist and MTP joints, and, when evaluating remission of RA, scanning at least wrist and MCP joints of the dominant hand. For both purposes primarily power Doppler US might be used since its results are less equivocal than those of greyscale US.     

Knowing the way home: strong philopatry of a highly mobile insect species, Brenthis ino

Mobility is crucial for the maintenance of viable metapopulations, but quantitative data to evaluate risks due to insufficient individual mobility of focal insect species are mostly lacking. We selected the butterfly Brenthis ino, a species typically confined to wet fallow grasslands in Central Europe and performed a mark–release–recapture study in a 3.2 ha study area with one big and one small patch of suitable habitat from 22 June to 23 July 2010. The position of each butterfly capture was measured with a GPS and transferred into a GIS. In total, we marked 984 individuals in 1,545 capture events and estimated that the cumulative population size was 2,400 individuals. The initial increase of adult males proceeded much faster than for females, similar to the protandrous population build-up known from other butterflies. Moved distances for both sexes usually did not exceed 80 m, and about 40 % of all individuals used less than 2 % of the available suitable habitat. All individuals switching to the other patch returned later to their patch of origin, confirming that B. ino is highly philopatric. We conclude that low effective mobility in B. ino produces much smaller home ranges than suggested by merely observing flight activities in the field, and that low tendencies towards long-distance movements significantly hamper the maintenance of metapopulations when patch density decreases due to landscape fragmentation.     

Trafficking of the IKs‐Complex in MDCK Cells: Site of Subunit Assembly and Determinants of Polarized Localization

The voltage‐gated potassium channel K_V7.1 is regulated by non‐pore forming regulatory KCNE β‐subunits. Together with KCNE1, it forms the slowly activating delayed rectifier potassium current I_Ks. However, where the subunits assemble and which of the subunits determines localization of the I_Ks‐complex has not been unequivocally resolved yet. We employed trafficking‐deficient K_V7.1 and KCNE1 mutants to investigate I_Ks trafficking using the polarized Madin‐Darby Canine Kidney cell line. We find that the assembly happens early in the secretory pathway but provide three lines of evidence that it takes place in a post‐endoplasmic reticulum compartment. We demonstrate that K_V7.1 targets the I_Ks‐complex to the basolateral membrane, but that KCNE1 can redirect the complex to the apical membrane upon mutation of critical K_V7.1 basolateral targeting signals. Our data provide a possible explanation to the fact that K_V7.1 can be localized apically or basolaterally in different epithelial tissues and offer a solution to divergent literature results regarding the effect of KCNE subunits on the subcellular localization of K_V7.1/KCNE complexes .     

A new species of Wellsopsyllus (Copepoda, Harpacticoida, Paramesochridae) from the deep Southern Ocean and remarks on its biogeography

The new deep-sea copepod species of the family Paramesochridae (Copepoda, Harpacticoida) presented here was collected during the scientific ANtarctic benthic DEEP-sea biodiversity cruise II (ANDEEP II) to the Weddell Abyssal Plain and western Weddell Sea and the CROZet natural iron bloom and EXport experiment (CROZEX cruise) to the Crozet Isles in the Indian Ocean. The new species has been allocated to the subgenus Wellsopsyllus within the genus Wellsopsyllus Kunz, 1981, based on the 1-segmented endopods and 3-segmented exopods of swimming legs 2–4. Furthermore, the new species shows a 1-segmented exopod of the antenna. Wellsopsyllus (W.) antarcticus sp. n. can be distinguished from its congeners by its small body size, the presence of two setae on the distal segment of the endopod of the first swimming leg, by the very small furcal rami, the extremely reduced endopods of second and third swimming legs, the reduced mandibular palp and maxillula, as well as by the size and armature of the fifth and sixth swimming legs in both sexes. Difficulties of the placement of the new species into a suitable genus show an insufficiency in the present family classification. In the future, a revision of the genus Wellsopsyllus is essential. With its presence in the western Weddell Sea and the Indian Ocean, the new species may have a wide distribution range. Furthermore, it is the first abyssal species of the genus Wellsopsyllus sampled outside of the Scotia Sea.     

The conserved oligomeric Golgi complex is involved in penetration resistance of barley to the barley powdery mildew fungus

Membrane trafficking is vital to plant development and adaptation to the environment. It is suggested that post‐Golgi vesicles and multivesicular bodies are essential for plant defence against directly penetrating fungal parasites at the cell wall. However, the actual plant proteins involved in membrane transport for defence are largely unidentified. We applied a candidate gene approach and single cell transient‐induced gene silencing for the identification of membrane trafficking proteins of barley involved in the response to the fungal pathogen Blumeria graminis f.sp. hordei. This revealed potential components of vesicle tethering complexes [putative exocyst subunit HvEXO70F‐like and subunits of the conserved oligomeric Golgi (COG) complex] and Golgi membrane trafficking (COPIγ coatomer and HvYPT1‐like RAB GTPase) as essential for resistance to fungal penetration into the host cell.     

Ala54Thr Fatty Acid-Binding Protein 2 (FABP2) Polymorphism in Recurrent Depression: Associations with Fatty Acid Concentrations and Waist Circumference

Background

Fatty acid (FA)-alterations may mediate the mutual association between Major Depressive Disorder (MDD) and cardiovascular disease (CVD). However, etiology of observed FA-alterations in MDD and CVD remains largely unclear. An interesting candidate may be a mutation in the fatty acid–binding protein 2 (FABP2)-gene, because it regulates dietary FA-uptake. Therefore, we aimed to test the hypotheses that in MDD-patients the FABP2 Ala54Thr-polymorphism would be (I) more prevalent than in sex- and age-matched controls, (II) associated with observed alterations in FA-metabolism, and (III) associated with CVD-risk factor waist circumference.

Methods

We measured concentrations of 29 different erythrocyte FAs, FABP2-genotype, and waist circumference in recurrent MDD-patients and matched never-depressed controls.

Results

FABP2-genotype distribution did not significantly differ between the 137 MDD-patients and 73 matched controls. However, patients with the Ala54Thr-polymorphism had (I) higher concentrations of especially eicosadienoic acid (C20:2ω6; P=.009) and other 20-carbon FAs, and associated (II) lower waist circumference (P=.019). In addition, FABP2-genotype effects on waist circumference in patients seemed (I) mediated by its effect on C20:2ω6, and (II) different from controls.

Conclusions

Although Ala54Thr-polymorphism distribution was not associated with recurrent MDD, our results indicate that FABP2 may play a role in the explanation of observed FA-alterations in MDD. For Ala54Thr-polymorphism patients, potentially adaptive conversion of increased bioavailable dietary precursors into eicosadienoic acid instead of arachidonic acid might be related to a low waist circumference. Because this is the first investigation of these associations, replication is warranted, preferably by nutrigenetic studies applying lipidomics and detailed dietary assessment.     

Effect of Alpha Linolenic Acid Supplementation on Serum Prostate Specific Antigen (PSA): Results from the Alpha Omega Trial

Background

Alpha linolenic acid (ALA) is the major omega-3 fatty acid in the diet. Evidence on health effects of ALA is not conclusive, but some observational studies found an increased risk of prostate cancer with higher intake of ALA. We examined the effect of ALA supplementation on serum concentrations of prostate-specific antigen (PSA), a biomarker for prostate cancer.

Methods

The Alpha Omega Trial (ClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT00127452","term_id":"NCT00127452"}}NCT00127452) was a double-blind, placebo-controlled trial of ALA and the fish fatty acids eicosapentanoic acid (EPA) and docosahexanoic acid (DHA) on the recurrence of cardiovascular disease, using a 2×2 factorial design. Blood was collected at the start and the end of the intervention period. The present analysis included 1622 patients with a history of a myocardial infarction, aged 60–80 years with an initial PSA concentration <4 ng/mL. They received either 2 g per day of ALA or placebo in margarine spreads for 40 months. T-tests and logistic regression were used to assess the effects of ALA supplementation on changes in serum PSA (both continuously and as a dichotomous outcome, cut-off point: >4 ng/mL).

Findings

Mean serum PSA increased by 0.42 ng/mL on placebo (n = 815) and by 0.52 ng/mL on ALA (n = 807), a difference of 0.10 (95% confidence interval: −0.02 to 0.22) ng/mL (P = 0·12). The odds ratio for PSA rising above 4 ng/mL on ALA versus placebo was 1.15 (95% CI: 0.84–1.58).

Interpretation

An additional amount of 2 g of ALA per day increased PSA by 0.10 ng/mL, but the confidence interval ranged from −0.02 to 0.22 ng/mL and included no effect. Therefore, more studies are needed to establish whether or not ALA intake has a clinically significant effect on PSA or prostate cancer.

Trial registration information

ClinicalTrials.gov; Identifier: {"type":"clinical-trial","attrs":{"text":"NCT00127452","term_id":"NCT00127452"}}NCT00127452. URL: http://www.clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT00127452","term_id":"NCT00127452"}}NCT00127452.     

Ecological Network Indicators of Ecosystem Status and Change in the Baltic Sea

Several marine ecosystems under anthropogenic pressure have experienced shifts from one ecological state to another. In the central Baltic Sea, the regime shift of the 1980s has been associated with food-web reorganization and redirection of energy flow pathways. These long-term dynamics from 1974 to 2006 have been simulated here using a food-web model forced by climate and fishing. Ecological network analysis was performed to calculate indices of ecosystem change. The model replicated the regime shift. The analyses of indicators suggested that the system’s resilience was higher prior to 1988 and lower thereafter. The ecosystem topology also changed from a web-like structure to a linearized food-web.