The role of phadiatop in the screening of respiratory allergy

Phadiatop is a new in vitro screening test for respiratory allergy. This test, based on the RAST procedure, detects in serum, the presence of specific IgE to a mixture of common inhalent allergens. Among 70 patients (26 children and 44 adults) consulting for respiratory syndrome, Phadiatop was positive in 31 cases. There were a good correlation between this new test and skin tests (59% for adults and 92% for children), total IgE (70% for adults and 65% for children) and RAST (93% for adults and 96% for children). Phadiatop, with a specificity of 100%, a sensitivity of 82% (76% for adults and 92% for children) and an efficiency of 90% (86% for adults and 96% for children), is a more accurate test than total IgE and could be an excellent in vitro screening test for respiratory allergy.     

Serum beta 2 microglobulin in adult myeloid acute leukemias

Serum beta 2 microglobulin levels, measured by radioimmunoassay (Phadebas test), were found increased in acute myeloid leukemias at diagnosis. Serum beta 2 microglobulin levels were significantly higher in patients with monocytic leukemias (13 patients, M4-M5 FAB classification) than in those with other cytological types (18 patients). Beta 2 microglobulin levels at diagnosis were correlated with serum lysozyme levels, but they were not correlated with blood blast counts, serum LDH and ferritin levels. 195 serum beta 2 microglobulin measurements were made serially in 30 patients with acute myeloid leukemias in first remission. Compared to values at diagnosis, beta 2 microglobulin levels in remission were significantly decreased. Out of 30 patients in remission 12 had increased serum beta 2 microglobulin levels (greater than 3 mg/l). Serial measurements were not predictive for relapses.     

Female wing spreading as acceptance signal in theDrosophila virilis group of species

Females of manyDrosophila species spread apart their wings prior to copulation. In the present study we found female wing spreading to provoke male copulation attempts inDrosophila virilis-group species, helping the males to attempt copulation when the female is ready to mate. The males of most species, however, rarely responded to female wing spreading by copulation attempt without licking the female genitalia before and/or after female wing spreading bout. Blocking the female genitalia (D. virilis, D. novamexicana) reduces males' tendency to attempt copulation after female wing spreading. In these, and most other species of the group, female wing spreading seems to be an efficient signal only when combined with stimuli from female genitalia.     

Facilitation promotes invasions in plant‐associated microbial communities

While several studies have established a positive correlation between community diversity and invasion resistance, it is less clear how species interactions within resident communities shape this process. Here, we experimentally tested how antagonistic and facilitative pairwise interactions within resident model microbial communities predict invasion by the plant–pathogenic bacterium Ralstonia solanacearum. We found that facilitative resident community interactions promoted and antagonistic interactions suppressed invasions both in the lab and in the tomato plant rhizosphere. Crucially, pairwise interactions reliably explained observed invasion outcomes also in multispecies communities, and mechanistically, this was linked to direct inhibition of the invader by antagonistic communities (antibiosis), and to a lesser degree by resource competition between members of the resident community and the invader. Together, our findings suggest that the type and strength of pairwise interactions can reliably predict the outcome of invasions in more complex multispecies communities.     

Tumor necrosis factor alpha enhances influenza A virus-induced expression of antiviral cytokines by activating RIG-I gene expression

Epithelial cells of the lung are the primary targets for respiratory viruses. Virus-carried single-stranded RNA (ssRNA) can activate Toll-like receptors (TLRs) 7 and 8, whereas dsRNA is bound by TLR3 and a cytoplasmic RNA helicase, retinoic acid-inducible protein I (RIG-I). This recognition leads to the activation of host cell cytokine gene expression. Here we have studied the regulation of influenza A and Sendai virus-induced alpha interferon (IFN-alpha), IFN-beta, interleukin-28 (IL-28), and IL-29 gene expression in human lung A549 epithelial cells. Sendai virus infection readily activated the expression of the IFN-alpha, IFN-beta, IL-28, and IL-29 genes, whereas influenza A virus-induced activation of these genes was mainly dependent on pretreatment of A549 cells with IFN-alpha or tumor necrosis factor alpha (TNF-alpha). IFN-alpha and TNF-alpha induced the expression of the RIG-I, TLR3, MyD88, TRIF, and IRF7 genes, whereas no detectable TLR7 and TLR8 was seen in A549 cells. TNF-alpha also strongly enhanced IKK epsilon mRNA and protein expression. Ectopic expression of a constitutively active form of RIG-I (deltaRIG-I) or IKK epsilon, but not that of TLR3, enhanced the expression of the IFN-beta, IL-28, and IL-29 genes. Furthermore, a dominant-negative form of RIG-I inhibited influenza A virus-induced IFN-beta promoter activity in TNF-alpha-pretreated cells. In conclusion, IFN-alpha and TNF-alpha enhanced the expression of the components of TLR and RIG-I signaling pathways, but RIG-I was identified as the central regulator of influenza A virus-induced expression of antiviral cytokines in human lung epithelial cells.     

Radioimmunological determination of the serum IgD

We describe a sensitive liquid phase radioimmunoassay for serum IgD. Extreme values obtained from 85 control patients sera are 0.2 and 121 mg/l with an arithmetic mean of 25 mg/l. In atopic patients (with high serum IgE levels), arithmetic mean is 47 mg/l.     

Spatiotemporal dynamics of plant occurrence in an urban forest fragment

The study area is an urban forest remnant in the city of Tampere (Finland). The presence of vascular plant species were surveyed in 1980 and again in 2000 within the 5 × 5 m grid cells covering the whole forest. The forest fragment has been influenced by three types of urban pressure: general ecological conditions (such as eutrophication due to increase of nitrogen), edge effect and local human disturbance. A general and spatially even eutrophication was reflected in the frequencies of C- and S-strategists as a shift towards to the C-point in the CSR triangle. The total number of native species (83 in 1980, 89 in 2000), typical Vaccinium type (VT)-forest species (32 in 1980, 31 in 2000) and aliens (57 in 1980, 68 in 2000) did change, but only to a moderate extent. The number of typical VT-forest species and native species were more common in central parts of the fragment. In terms of the number of species, the forest has been relatively resistant to date to major changes. However, the average number of native plant species per grid cell increased from 13.7 to 14.4, the average number of aliens increased from 2.0 to 4.2 and the average number of typical VT-forest species decreased from 5.5 to 5.0. Natives were spatially concentrated in the centre in 1980, but in 2000 they were more evenly distributed. The edge has offered habitats for new species, but the typical VT-forest species of the original sub-xeric forest are slowly diminishing.     

Screening of microbes for novel acidic cutinases and cloning and expression of an acidic cutinase from Aspergillus niger CBS 513.88

Isolates from gardening waste compost and 38 culture collection microbes were grown on agar plates at pH 4.0 with the cutinase model substrate polycaprolactone as a carbon source. The strains showing polycaprolactone hydrolysis were cultivated in liquid at acidic pH and the cultivations were monitored by assaying the p-nitrophenyl butyrate esterase activities. Culture supernatants of four strains were analyzed for the hydrolysis of tritiated apple cutin at different pHs. Highest amounts of radioactive hydrolysis products were detected at pHs below 5. The hydrolysis of apple cutin by the culture supernatants at acidic pH was further confirmed by GC–MS analysis of the hydrolysis products. On the basis of screening, the acidic cutinase from Aspergillus niger CBS 513.88 was chosen for heterogeneous production in Pichia pastoris and for analysis of the effects of pH on activity and stability. The recombinant enzyme showed activity over a broad range of pHs with maximal activity between pH 5.0 and 6.5. Activity could be detected still at pH 3.5.