Infrared Thermography as a Diagnostic Tool for Pododermatitis in Captive Greater Flamingos (Phoenicopterus roseus)

This cross-sectional study investigated the use of infrared thermography as a diagnostic tool for pododermatitis in captive greater flamingos (Phoenicopterus roseus). Photographs and thermal images were obtained for 775 feet from 408 flamingos held at three UK zoological collections. The feet were divided into eight regions, which were assigned a score for hyperkeratosis, fissures, nodules and papillomatous growths according to a previously defined scoring system. Minimum, mean and maximum temperatures were recorded for each region. 97 feet (12.5%) were scored as normal (no lesions or only mild hyperkeratosis), whilst 678 (87.5%) were scored as abnormal. It was found that 99.9% (95% confidence interval (CI): 99.3–100%) of the scored feet exhibited hyperkeratosis, 61.7% (95% CI: 58.2–65.1%) fissures, 16.0% (95% CI: 13.5–18.8%) nodules and 38.5% (95% CI: 35.0–42.0%) papillomatous growths. Thermal data assessed using general linear mixed effect modelling showed that regional and individual bird temperature differences accounted for most of the temperature variation, but there was a statistically significant (P<0.05) difference between regions with nodules versus regions without when using maximum temperatures. Intra- and inter-foot variation, using a regional correction factor and ankle temperatures, was assessed for 272 birds, where temperature distributions for each lesion type were compared with that of normal regions using t-tests. A statistically significant difference (P<0.05) was found between corrected values for regions with hyperkeratosis and papillomatous growths compared with normal, but no difference was found for fissures or nodules. Despite the differences found, the results suggest that infrared thermography may not be a practical diagnostic tool for pododermatitis in flamingos due to wide temperature variations between and within normal feet and a great degree of overlap of temperatures between normal and abnormal feet

Alu repeats increase local recombination rates

BACKGROUND: Recombination rates vary widely across the human genome, but little of that variation is correlated with known DNA sequence features. The genome contains more than one million Alu mobile element insertions, and these insertions have been implicated in non-homologous recombination, modulation of DNA methylation, and transcriptional regulation. If individual Alu insertions have even modest effects on local recombination rates, they could collectively have a significant impact on the pattern of linkage disequilibrium in the human genome and on the evolution of the Alu family itself. RESULTS: We carried out sequencing, SNP identification, and SNP genotyping around 19 AluY insertion loci in 347 individuals sampled from diverse populations, then used the SNP genotypes to estimate local recombination rates around the AluY loci. The loci and SNPs were chosen so as to minimize other factors (such as SNP ascertainment bias and SNP density) that could influence recombination rate estimates. We detected a significant increase in recombination rate within ~2 kb of the AluY insertions in our African population sample. To test this observation against a larger set of AluY insertions, we applied our locus- and SNP-selection design and analyses to the HapMap Phase II data. In that data set, we observed a significantly increased recombination rate near AluY insertions in both the CEU and YRI populations. CONCLUSION: We show that the presence of a fixed AluY insertion is significantly predictive of an elevated local recombination rate within 2 kb of the insertion, independent of other known predictors. The magnitude of this effect, approximately a 6% increase, is comparable to the effects of some recombinogenic DNA sequence motifs identified via their association with recombination hot spots

Serological evidence for the presence of wobbly possum disease virus in Australia

Wobbly possum disease virus (WPDV) is an arterivirus that was originally identified in common brushtail possums (Trichosurus vulpecula) in New Zealand, where it causes severe neurological disease. In this study, serum samples (n = 188) from Australian common brushtail, mountain brushtail (Trichosurus cunninghami) and common ringtail (Pseudocheirus peregrinus) possums were tested for antibodies to WPDV using ELISA. Antibodies to WPDV were detected in possums from all three species that were sampled in the states of Victoria and South Australia. Overall, 16% (30/188; 95% CI 11.0-22.0) of possums were seropositive for WPDV and 11.7% (22/188; 95% CI 7.5-17.2) were equivocal. The frequency of WPDV antibody detection was the highest in possums from the two brushtail species. This is the first reported serological evidence of infection with WPDV, or an antigenically similar virus, in Australian possums, and the first study to find antibodies in species other than common brushtail possums. Attempts to detect viral RNA in spleens by PCR were unsuccessful. Further research is needed to characterise the virus in Australian possums and to determine its impact on the ecology of Australian marsupials

Imaging of the diffusion of single band 3 molecules on normal and mutant erythrocytes

Membrane-spanning proteins may interact with a variety of other integral and peripheral membrane proteins via a diversity of protein-protein interactions. Not surprisingly, defects or mutations in any one of these interacting components can impact the physical and biological properties on the entire complex. Here we use quantum dots to image the diffusion of individual band 3 molecules in the plasma membranes of intact human erythrocytes from healthy volunteers and patients with defects in one of their membrane components, leading to well-known red cell pathologies (hereditary spherocytosis, hereditary elliptocytosis, hereditary hydrocytosis, Southeast Asian ovalocytosis, and hereditary pyropoikilocytosis). After characterizing the motile properties of the major subpopulations of band 3 in intact normal erythrocytes, we demonstrate that the properties of these subpopulations of band 3 change significantly in diseased cells, as evidenced by changes in the microscopic and macroscopic diffusion coefficients of band 3 and in the compartment sizes in which the different band 3 populations can diffuse. Because the above membrane abnormalities largely arise from defects in other membrane components (eg, spectrin, ankyrin), these data suggest that single particle tracking of band 3 might constitute a useful tool for characterizing the general structural integrity of the human erythrocyte membrane

An insulator with barrier-element activity promotes α-spectrin gene expression in erythroid cells

Understanding mechanisms controlling expression of the α-spectrin gene is important for understanding erythropoiesis, membrane biogenesis, and spectrin-linked hemolytic anemia. We showed previously that a minimal α-spectrin promoter directed low levels of expression only in early erythroid development, indicating elements outside the promoter are required for expression in adult erythrocytes. Addition of noncoding exon 1′ and intron 1′ conferred a 10-fold increase in activity in reporter gene assays. In this report, we used a transgenic mouse model to show that addition of exon 1′ and intron 1′ to the α-spectrin promoter conferred tissue-specific expression of a linked Aγ-globin gene in erythroid cells at all developmental stages. Expression was nearly position-independent, as 21 of 23 lines expressed the transgene, and γ-globin protein was present in 100% of erythrocytes, indicating uniform expression. Additional in vivo studies revealed that exon 1′ functions as an insulator with barrier-element activity. Chromatin immunoprecipitation assays demonstrated that this region was occupied by the upstream stimulatory factors 1/2 (USF1/USF2), similar to the well-characterized chicken HS4 insulator. These data identify the first barrier element described in an erythrocyte membrane protein gene and indicate that exon 1′ and intron 1′ are excellent candidate regions for mutations in patients with spectrin-linked hemolytic anemia