Dynamics of immune cell recruitment during West Nile encephalitis and identification of a new CD19+B220-BST-2+ leukocyte population

West Nile virus (WNV) is an emerging neurotropic flavivirus. We investigated the dynamics of immune cell recruitment in peripheral tissues and in the CNS during WNV encephalitis in an immunocompetent mouse model. In the periphery, immune cell expansion can successfully limit viremia and lymphoid tissue infection. However, viral clearance in the periphery is too late to prevent viral invasion of the CNS. In the CNS, innate immune cells, including microglia/macrophages, NK cells, and plasmacytoid dendritic cells, greatly expand as the virus invades the brain, whereas B and T cells are recruited after viral invasion, and fail to control the spread of the virus. Thus, the onset of WNV encephalitis was correlated both with CNS viral infection and with a large local increase of innate immune cells. Interestingly, we identify a new immune cell type: CD19(+)B220(-) BST-2(+), which we name G8-ICs. These cells appear during peripheral infection and enter the CNS. G8-ICs express high levels of MHC class II, stain for viral Ag, and are localized in the paracortical zone of lymph nodes, strongly suggesting they are previously unidentified APCs that appear in response to viral infection.     

Population Dynamics and Diversity of Viruses,Bacteria and Phytoplankton in a Shallow Eutrophic Lake

We have studied the temporal variation in viral abundances and community assemblage in the eutrophic Lake Loosdrecht through epifluorescence microscopy and pulsed field gel electrophoresis (PFGE). The virioplankton community was a dynamic component of the aquatic community, with abundances ranging between 5.5 x 10(7) and 1.3 x 10(8) virus-like particles ml(-1) and viral genome sizes ranging between 30 and 200 kb. Both viral abundances and community composition followed a distinct seasonal cycle, with high viral abundances observed during spring and summer. Due to the selective and parasitic nature of viral infection, it was expected that viral and host community dynamics would covary both in abundances and community composition. The temporal dynamics of the bacterial and cyanobacterial communities, as potential viral hosts, were studied in addition to a range of environmental parameters to relate these to viral community dynamics. Cyanobacterial and bacterial communities were studied applying epifluorescence microscopy, flow cytometry, and denaturing gradient gel electrophoresis (DGGE). Both bacterial and cyanobacterial communities followed a clear seasonal cycle. Contrary to expectations, viral abundances were neither correlated to abundances of the most dominant plankton groups in Lake Loosdrecht, the bacteria and the filamentous cyanobacteria, nor could we detect a correlation between the assemblage of viral and bacterial or cyanobacterial communities during the overall period. Only during short periods of strong fluctuations in microbial communities could we detect viral community assemblages to covary with cyanobacterial and bacterial communities. Methods with a higher specificity and resolution are probably needed to detect the more subtle virus-host interactions. Viral abundances did however relate to cyanobacterial community assemblage and showed a significant positive correlation to Chl-a as well as prochlorophytes, suggesting that a significant proportion of the viruses in Lake Loosdrecht may be phytoplankton and more specific cyanobacterial viruses. Temporal changes in bacterial abundances were significantly related to viral community assemblage, and vice versa, suggesting an interaction between viral and bacterial communities in Lake Loosdrecht.     

Spatial modelling of the barn owl Tyto alba habitat using landscape characteristics derived from SPOT data

Landscape parameters extracted from classified SPOT satellite imagery are used as independent variables for predicting potential habitat areas of the barn owl Tyto alba in a landscape north-east of Brussels, Belgium Field data on the nest sites, recorded during 9 yr, are used as the dependent variable A canonical correlation analysis of the landscape characteristics of 'successful breeding and non-breeding sites' selects a set of most significant parameters contributing to the distinction between suitable and unsuitable breeding habitat parameters measuring the spatial configuration and fragmentation of landscape elements, such as deciduous woods and grasslands, in combination with some visual characteristics of the open spaces in the landscape The selected set of parameters formed the basis for the calculation of a habitat model, whereby potential breeding sites could be located throughout the complete study area, at specific levels of confidence The results showed the relevance of this method for landscape ecological research and nature conservation planning     

Set-based particle swarm optimization applied to the multidimensional knapsack problem

Particle swarm optimization algorithms have been successfully applied to discrete/valued optimization problems. However, in many cases the algorithms have been tailored specifically for the problem at hand. This paper proposes a generic set-based particle swarm optimization algorithm for use in discrete-valued optimization problems that can be formulated as set-based problems. A detailed sensitivity analysis of the parameters of the algorithm is conducted. The performance of the proposed algorithm is then compared against three other discrete particle swarm optimization algorithms from literature using the multidimensional knapsack problem and is shown to statistically outperform the existing algorithms.     

The effect of inhibition of endothelial cell cyclooxygenase on arterial thrombosis

Arterial platelet thrombosis was induced in vivo in a branch of the mesenteric artery of the white Wistar rat by topical superfusion by adenosine diphosphate following local de-endothelialization of the dissected segment by means of a small electrical current. Detection of the thrombotic phenomena was performed by projection of the arterial segment onto a set of light sensitive elements, wich allows the registration of several discriminating parameters. The addition of arachidonic acid to the superfusing mixture results in an increase in thromboformation; this increasing effect can be blocked completely by prior inhibition od the vessel wall cyclooxygenase activity by inhibitors such as flurbiprofen or indomethacin. We therefore concluded that the arachidonate cascade, triggered within the endothelial cells, is involved in platelet-vessel wall interaction leading ultimately to local thrombosis.     

Impact of Financial Liberalization on Banking Sectors Performance from Central and Eastern European Countries

In this paper we analyse the impact of financial liberalization and reforms on the banking performance in 17 countries from CEE for the period 2004–2008 using a two-stage empirical model that involves estimating bank performance in the first stage and assessing its determinants in the second one. From our analysis it results that banks from CEE countries with higher level of liberalization and openness are able to increase cost efficiency and eventually to offer cheaper services to clients. Banks from non-member EU countries are less cost efficient but experienced much higher total productivity growth level, and large sized banks are much more cost efficient than medium and small banks, while small sized banks show the highest growth in terms of productivity.     

MAP kinase activation by hypoosmotic stress of tobacco cell suspensions: towards the oxidative burst response?

Hypoosmotic stress activates a phosphorylation-dependent oxidative burst. In-gel kinase assays were performed to characterize the protein kinases that could be implicated in osmoregulation and in the activation of the oxidative burst. Hypoosmotic stress activated several kinases among which 50 and 46 kDa proteins displayed mitogen-activated protein kinase (MAP kinase) properties. They phosphorylated myelin basic protein in the absence of calcium, were recognized by antibodies directed against human MAP kinases, and were phosphorylated on tyrosine. Immunoprecipitation with an antibody directed against the tobacco MAP kinase Ntf4 showed that at least one of the activated kinases would be Ntf4-like. Apigenin, a MAP kinase and cyclin-dependent kinase inhibitor which prevents the hypoosmotically induced oxidative burst ( Cazaléet al. 1998 ; Plant Physiol. 116, 659–669), inhibited these kinases in vitro suggesting that they may play a role in the activation of the oxidative burst. Like the oxidative response, activation of the kinases depended on extracellular calcium influx and protein kinases sensitive to staurosporine and 6-DMAP. However, kinase activation did not depend on effluxes through anion channels or on the oxidative burst. Two-dimensional in-gel kinase assays revealed the presence of three protein kinases with an apparent molecular mass of 50 kDa and one of 46 kDa, all four being activated by hypoosmotic stress. The same kinases were also activated by oligogalacturonides and salicylic acid, underlying the importance of these MAP kinases as common components of different signaling pathways triggered by different extracellular stimuli.     

Bioactive aristolactams from Piper umbellatum

Four alkaloids named piperumbellactams A-D (1-4) were isolated from branches of Piper umbellatum together with known N-hydroxyaristolam II (5), N-p-coumaroyl tyramine (6), 4-nerolidylcatechol (7), N-trans-feruloyltyramine, E-3-(3,4-dihydroxyphenyl)-N-2-[4-hydroxyphenylethyl]-2-propenamide, beta-amyrin, friedelin, apigenin 8-C-neohesperidoside, acacetin 6-C-beta-d-glucopyranoside, beta-sitosterol, its 3-O-beta-d-glucopyranoside and its 3-O-beta-d-[6'-dodecanoyl]-glucopyranoside. Glycosidase inhibition, antioxidant and antifungal activities of these compounds were evaluated. Compounds 1-3 showed moderate alpha-glucosidase enzyme inhibition with IC50 values 98.07+/-0.44, 43.80+/-0.56 and 29.64+/-0.46, respectively. In DPPH radical scavenging assay, compounds 2, 3 and 6 showed potent inhibitory activity while compounds 4, 5 and 7 showed potent antifungal activity.     

Life Expectancy in a Large Cohort of Type 2 Diabetes Patients Treated in Primary Care (ZODIAC-10)

Background

Most longitudinal studies showed increased relative mortality in individuals with type 2 diabetes mellitus until now. As a result of major changes in treatment regimes over the past years, with more stringent goals for metabolic control and cardiovascular risk management, improvement of life expectancy should be expected. In our study, we aimed to assess present-day life expectancy of type 2 diabetes patients in an ongoing cohort study.

Methodology and Principal Findings

We included 973 primary care type 2 diabetes patients in a prospective cohort study, who were all participating in a shared care project in The Netherlands. Vital status was assessed from May 2001 till May 2007. Main outcome measurement was life expectancy assessed by transforming actual survival time to standardised survival time allowing adjustment for the baseline mortality rate of the general population. At baseline, mean age was 66 years, mean HbA_1c 7.0%. During a median follow-up of 5.4 years, 165 patients died (78 from cardiovascular causes), and 17 patients were lost to follow-up. There were no differences in life expectancy in subjects with type 2 diabetes compared to life expectancy in the general population. In multivariate Cox regression analyses, concentrating on the endpoints ‘all-cause’ and cardiovascular mortality, a history of cardiovascular disease: hazard ratio (HR) 1.71 (95% confidence interval (CI) 1.23–2.37), and HR 2.59 (95% CI 1.56–4.28); and albuminuria: HR 1.72 (95% CI 1.26–2.35), and HR 1.83 (95% CI 1.17–2.89), respectively, were significant predictors, whereas smoking, HbA_1c, systolic blood pressure and diabetes duration were not.

Conclusions

This study shows a normal life expectancy in a cohort of subjects with type 2 diabetes patients in primary care when compared to the general population. A history of cardiovascular disease and albuminuria, however, increased the risk of a reduction of life expectancy. These results show that, in a shared care environment, a normal life expectancy is achievable in type 2 diabetes patients.