Characterisation and expression of SPLUNC2, the human orthologue of rodent parotid secretory protein

We recently described the Palate Lung Nasal Clone (PLUNC) family of proteins as an extended group of proteins expressed in the upper airways, nose and mouth. Little is known about these proteins, but they are secreted into the airway and nasal lining fluids and saliva where, due to their structural similarity with lipopolysaccharide-binding protein and bactericidal/permeability-increasing protein, they may play a role in the innate immune defence. We now describe the generation and characterisation of novel affinity-purified antibodies to SPLUNC2, and use them to determine the expression of this, the major salivary gland PLUNC. Western blotting showed that the antibodies identified a number of distinct protein bands in saliva, whilst immunohistochemical analysis demonstrated protein expression in serous cells of the major salivary glands and in the ductal lumens as well as in cells of minor mucosal glands. Antibodies directed against distinct epitopes of the protein yielded different staining patterns in both minor and major salivary glands. Using RT-PCR of tissues from the oral cavity, coupled with EST analysis, we showed that the gene undergoes alternative splicing using two 5' non-coding exons, suggesting that the gene is regulated by alternative promoters. Comprehensive RACE analysis using salivary gland RNA as template failed to identify any additional exons. Analysis of saliva showed that SPLUNC2 is subject to N-glycosylation. Thus, our study shows that multiple SPLUNC2 isoforms are found in the oral cavity and suggest that these proteins may be differentially regulated in distinct tissues where they may function in the innate immune response

Distributional Patterns of Pseudacteon Associated with the Solenopsis saevissima Complex in South America

Classical biological control efforts against imported fire ants have largely involved the use of Pseudacteon parasitoids. To facilitate further exploration for species and population biotypes a database of collection records for Pseudacteon species was organized, including those from the literature and other sources. These data were then used to map the geographical ranges of species associated with the imported fire ants in their native range in South America. In addition, we found geographical range metrics for all species in the genus and related these metrics to latitude and host use. Approximately equal numbers of Pseudacteon species were found in temperate and tropical regions, though the majority of taxa found only in temperate areas were found in the Northern Hemisphere. No significant differences in sizes of geographical ranges were found between Pseudacteon associated with the different host complexes of fire ants despite the much larger and systemic collection effort associated with the S. saevissima host group. The geographical range of the flies was loosely associated with both the number of hosts and the geographical range of their hosts. Pseudacteon with the most extensive ranges had either multiple hosts or hosts with broad distributions. Mean species richnesses of Pseudacteon in locality species assemblages associated with S. saevissima complex ants was 2.8 species, but intensively sampled locations were usually much higher. Possible factors are discussed related to variation in the size of geographical range, and areas in southern South America are outlined that are likely to have been under-explored for Pseudacteon associated with imported fire ants

Ecological inference and spatial heterogeneity: an entropy-based distributionally weighted regression approach

In this article we compare two competing approaches to ecological modelling using test data. The first approach is based on the "traditional" method of Ordinary Least Squares (OLS), assuming constancy of parameters across disaggregated spatial units (spatial homogeneity). The second (new) approach is based on the method of Generalised Cross-Entropy (GCE), assuming varying parameters (spatial heterogeneity). The latter approach is designated as entropy-based "distributionally weighted regression" (DWR). The two approaches are tested in a real-world application, using data on per-capita GDP for the 17 regions and some covariates for the 50 provinces of Spain. Specifically, the performances of the two approaches are assessed by examining their capability in tracking the actual per-capita GDP data for the provinces (while treating them as if they were not observed by the econometrician), and in showing evidence of spatial heterogeneity. Our findings indicate that the GCE varying-parameter approach outperforms the OLS approach in terms of predictive power. Specifically, we find that the GCE predictions make efficient use of the lower-level information that is available. In addition, it is shown that entropy-based DWR has some potential as a useful technique for investigating spatially heterogeneous relationships at the lower level of analysis that might otherwise be overlooked. Copyright (c) 2006 the author(s). Journal compilation (c) 2006 RSAI.

Neural networks for regional employment forecasts: are the parameters relevant?

Neural networks, Sensitivity analysis, Employment forecasts, Local labour markets, C45, E27, R23,