Differential effects of heparin on NO and tumor necrosis factor-alpha production in bovine blood mononuclear cells stimulated with Salmonella typhimurium lipopolisaccharide.

We investigated the influence of heparin, one of the extracellular matrix (ECM) components, on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by bovine peripheral blood mononuclear cells (PBMC) and monocytes left to adhere for 2 (freshly adherent monocytes) and 48 h (resting monocytes), activated with Salmonella typhimurium lipopolysaccharide (LPS). After 24-h stimulation with LPS, heparin (100 microg/ml) increased (by about 40%) NO production by peripheral blood mononuclear cells and by freshly adherent monocytes. However, it did not change NO synthesis by the resting monocytes. Unlike its influence on NO level, heparin diminished TNF-alpha production by PBMC and monocytes stimulated with LPS. Microscopical examination of PBMC stained with biotin-labeled heparin, showed that both lymphocytes and monocytes were able to bind this glycosaminoglycan. We suggest that heparin, as a component of ECM, modulates the early response of monocytes to exogenous stimuli.     

Transmission of Theileriosis in the Traditional Farming Sector in the Southern Province of Zambia during 1995–1996

The incidence of first contact with the protozoan Theileria parva was determined in three traditional cattle herds in the Southern Province of Zambia in 1995 and 1996. The majority of first contacts occurred during the dry season in June, July and August, at a time of nymphal activity and in the absence of Rhipicephalus appendiculatus adults, indicating that larva to nymph transmission plays a more prominent role than nymph to adult transmission under the prevailing conditions.     

Low-CO2 Energy Pathways versus Emission Control Policies in Acidification Reduction

Integrated assessment models were applied to analyze the side-benefits of structural changes in the energy systems of Finland and the EU to reduce acidity critical load exceedances in Finland. The acidification reduction potential of structural measures, induced by the need to restrict carbon dioxide (CO₂) emissions, was compared with international agreements limiting acidifying emissions. The impacts of the UN/ECE Gothenburg protocol and the European Commission's proposal for a National Emission Ceilings (NEC) Directive were assessed together with domestic and bilateral policy scenarios. The study utilized point-source emission databases of Finland and the neighboring areas and a meso-scale deposition model together with the Europewide transfer matrices of the EMEP/MSC-W and European emission scenarios of IIASA. Further technical reduction measures in the adjacent large sulfur emission sources in Russia would reduce considerably deposition to nearby Finnish areas. Energy saving and shifts in the EU energy system towards less carbon-intensive fuels instead of further technical emission controls were found to have significant potential in limiting acidifying deposition. Implementation of the Kyoto protocol in the EU could reduce the Finnish areas at risk of acidification more than the Gothenburg protocol and the NEC Directive together.     

Development and reproduction of Adalia bipunctata (Coleoptera: Coccinellidae) on eggs of Ephestia kuehniella (Lepidoptera: Phycitidae) and pollen

Due to growing criticism over the use of non-indigenous coccinellids, the two-spot ladybird, Adalia bipunctata (L.), has enjoyed increasing attention for aphid biocontrol in Europe. In the current study, eggs of the Mediterranean flour moth, Ephestia kuehniella Zeller, whether or not supplemented with bee pollen, were evaluated as a factitious food for larvae and adults of A. bipunctata. The predator showed slower larval development and lower survival when reared on live pea aphids, Acyrthosiphon pisum (Harris), than on E. kuehniella eggs. Survival on gamma-irradiated eggs of E. kuehniella was superior to that on frozen flour moth eggs, but other developmental characteristics were similar. Adults of A. bipunctata reared on Ac. pisum were only half as fecund as those offered irradiated or frozen E. kuehniella eggs, but egg hatch was markedly better on live aphids than on flour moth eggs (61 versus 20-27%, respectively). However, when a diet of flour moth eggs was supplemented with frozen moist bee pollen, egg hatch of A. bipunctata was equally as good as on live aphids. Supplementing flour moth eggs with dry pollen did not yield satisfactory results. Only 10% of larvae reached adulthood on moist bee pollen alone and resulting adults weighed less than half as much as those obtained on flour moth eggs. Our findings indicate that A. bipunctata is able to compensate for a suboptimal diet of animal prey by supplementary feeding on flower pollen. It is concluded that pollinivory may be a crucial trait for both the rearing of this natural enemy and its use in biological control programmes.     

Evaluation of the indirect fluorescent antibody test as a diagnostic tool for East Coast fever in eastern Zambia

Serological surveys using the schizont indirect fluorescence antibody test (IFAt) are routinely carried out to monitor the Theileria parva infection prevalence. The present study evaluates the diagnostic accuracy of the IFAt in eastern Zambia, where the transmission of T. parva is highly seasonal. The data set resulted from a sentinel herd (n = 105 animals) study carried out between 1995 and 2000 and was split into an epidemic period, during which the majority of the cattle became infected, and an endemic period with seasonal disease incidence in calves. In the epidemic period the T. parva seroprevalence followed closely the build up of the herd immunity. In the endemic period the seroprevalence fluctuates considerably although most of the animals had been infected. Overall, the diagnostic sensitivity of the IFA test was 55% at cut-off titre 1:40 and 28% at cut-off 1:160. The specificity of the test was 86 and 95%, respectively. A logistic regression model demonstrates that the sensitivity is significantly lower when the T. parva transmission is low (p < 0.01). The analysis of receiver operator characteristic curves classifies the test as moderately accurate (area under the curve, AUC = 0.79) during the epidemic period and less accurate in the endemic period (AUC = 0.63). Neonatal serology surveys yield a better estimate of the infection prevalence. The sensitivity of the neonatal test was 73% at cut-off titre 1:40 and 24% at cut-off 1:160.     

Requirement for coronin 1 in T lymphocyte trafficking and cellular homeostasis

The evolutionarily conserved actin-related protein (Arp2/3) complex is a key component of actin filament networks that is dynamically regulated by nucleation-promoting and inhibitory factors. Although much is known about actin assembly, the physiologic functions of inhibitory proteins are unclear. We generated coronin 1-/- mice and found that coronin 1 exerted an inhibitory effect on cellular steady-state F-actin formation via an Arp2/3-dependent mechanism. Whereas coronin 1 was required for chemokine-mediated migration, it was dispensable for T cell antigen receptor functions in T cells. Moreover, actin dynamics, through a mitochondrial pathway, was linked to lymphocyte homeostasis.     

Economic burden of bovine trypanosomosis in three villages of Metekel zone,Northwest Ethiopia

The study was carried out to assess the economic burden of trypanosomosis in three villages of the Metekel zone in 2009. The disease was found to cause substantial economic losses through cattle mortality, drug purchase, and draft power loss of infected oxen. The farmers in the area were spending a significantly (p < 0.05) higher amount of money for the treatment of trypanosomosis than all other diseases combined. The overall mortality rate of cattle due to trypanosomosis was 4.4%. The mortality was significantly higher (p < 0.05) in an area where trypanosomosis prevalence was also higher. Many of the farmers prioritized losses of draft power as the most important impact of the disease. The overall prevalence of the disease was 12.1%. The disease burden was significantly (p < 0.05) higher in the rainy season than at other times of the year. In general, farmers had good knowledge on the signs and seasonality of trypanosomosis. Thus, tsetse suppression activities that involve the local community can be an important tool towards minimizing the economic burden of the disease in the area.     

Bayes and diagnostic testing

Interpretation of the result of a diagnostic test depends not only on the actual test result(s) but also on information external to this result, namely the test's sensitivity and specificity. This external information (also called prior information) must be combined with the data to yield the so-called updated, posterior estimates of the true prevalence and the test characteristics. The Bayesian approach offers a natural, intuitive framework in which to carry out this estimation process. The influence of the prior information on the final result may not be ignored. Guidance for the choice of prior information not in conflict with the data can be obtained from a set of statistics and indices (DIC, p(D), Bayes-p).     

Effect of host factors on the susceptibility of Rhododendron to Phytophthora ramorum

Phytophthora ramorum causes sudden oak death (SOD) in western coastal forests of the USA. In Europe, the pathogen is mainly present in the nursery industry, particularly on Rhododendron. Because of the primary role of Rhododendron as a host and potentially as a vector, the effect of Rhododendron host factors on P. ramorum susceptibility and sporulation was investigated. Inoculation methods using either wounded or non‐wounded detached leaves were applied to 59 Rhododendron cultivars and 22 botanical species, replicated in three separate years. All Rhododendron species and cultivars were susceptible when using wounded leaves, but not when using non‐wounded leaves, suggesting a resistance mechanism operating at the level of leaf penetration. Using a regression tree analysis, the cultivars and species were split into four susceptibility classes. Young leaves were more susceptible than mature leaves when wounded, but less susceptible when non‐wounded. This effect was not correlated with leaf hydrophobicity or the number of leaf hairs. The presence or the type of rootstock did not affect the cultivar susceptibility level. Sporangia and chlamydospore production in the leaf lesions varied widely among Rhododendron cultivars and was not correlated with the susceptibility level. The susceptibility to P. ramorum correlated well with the susceptibility to P. citricola and P. hedraiandra × cactorum, suggesting that the resistance mechanisms against these species are non‐specific. Susceptibility to P. kernoviae was low for most cultivars. These findings have implications for detection, spread and disease control, and are therefore important in pest risk assessment.     

Mangrove species zonation and soil redox state,sulphide concentration and salinity in Gazi Bay (Kenya), a preliminary study

The relationship between soil redox state, sulphide concentration, salinity and spatial patterns of mangrove species distribution was investigated in the mangrove forest of Gazi Bay (Kenya). Field measurements were conducted to examine the relationship between species distribution along a band transect of 280m and soil redox potential (Eh) and sulphide patterns, as well as the indirectly related (through flooding regimes) soil salinity. Of the three major species Avicenniamarina, Ceriops tagal and Rhizophoramucronata present along the transect, only the distribution of the latter correlated with the measured soil variables, R. mucronata being absent from the lessreduced zone with high salinity. Bruguieragymnorhiza and Heritieralittoralis occur in minor populations, they are restricted to the saline, sulphidepoor and lessreduced substrates. From the results it is concluded that soil redox potential (Eh), sulphide concentration and salinity may contribute to structure mangroves through the distribution of dominant species, however in combination with other environmental conditions and processes of vegetation dynamics.