Seroprevalence of <Emphasis Type="Italic">Borrelia burgdorferi</Emphasis> sensu lato and <Emphasis Type="Italic">Anaplasma phagocytophilum</Emphasis> in Danish horses

Background

Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses.

Methods

A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against B. burgdorferi sensu lato and A. phagocytophilum by the use of the SNAP^®4DX ^® ELISA test.

Results

Overall, 29.0% of the horses were seropositive for B. burgdorferi sensu lato whereas 22.3% were seropositive for A. phagocytophilum.

Conclusions

Antibodies against B burgdorferi sensu lato and A. phagocytophilum are commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.

     

Estimates of DNA and protein sequence divergence: an examination of some assumptions

Some of the assumptions underlying estimates of DNA and protein sequence divergence are examined. A solution for the variance of these estimates that allows for different mutation rates and different population sizes in each species and for an arbitrary structure in the initial population is obtained. It is shown that these conditions do not strongly affect estimates of divergence. In general, they cause the variance of divergence to be smaller than a binomial variance. Thus, the binomial variance that is usually assumed for these estimates is safely conservative. It is shown that variability in the mutation rate among sites can have an effect as large as or larger than variability in the mutation rate among bases. Variability in the mutation rate among bases and among sites causes the number of substitutions between two sequences to be underestimated. Protein and DNA sequences from several species are collected to estimate the variability in mutation rates among sites. When many homologous sequences are known, standard methods to estimate this variability can be used. The estimates of this variability show that this factor is important when considering the spectrum of spontaneous mutations and is strongly reflected in the divergence of sequences. Smaller variability is found for the third position of codons than for the first and second codon positions. This may be because of less selective constraints on this position or because the third position has been saturated with mutations for the sequences examined.      

Molecular phylogeny of diplomonads and enteromonads based on SSU rRNA,alpha-tubulin and HSP90 genes: Implications for the evolutionary history of the double karyomastigont of diplomonads

Background  

Fornicata is a relatively recently established group of protists that includes the diplokaryotic diplomonads (which have two similar nuclei per cell), and the monokaryotic enteromonads, retortamonads and Carpediemonas, with the more typical one nucleus per cell. The monophyly of the group was confirmed by molecular phylogenetic studies, but neither the internal phylogeny nor its position on the eukaryotic tree has been clearly resolved.     

Statins but not fibrates improve the atherogenic to anti-atherogenic lipoprotein particle ratio: a randomized crossover study

Background  

Prior studies suggested low density lipoprotein particle (LDLP) size is a predictor of atherosclerosis. Knowledge of effects of lipid lowering drugs on lipoprotein subclasses is useful. We treated subjects with hyperlipidemia sequentially with statins and fibrates, the 2 main classes of lipid lowering therapy and studied changes in NMR lipoprotein subclasses.     

New insights in Salicornia L. and allied genera (Chenopodiaceae) inferred from nrDNA sequence data

A phylogenetic analysis was performed based on ITS DNA sequences of fourteen samples from different sources of six species of Salicornia, the three allied genera Arthrocnemum, Sarcocornia and Halocnemum of the same tribe Salicornieae, and other genera of the subfamily Salicornioideae used in previous studies. Bassia hirsuta, Camphorosma monspeliaca (subfamily Chenopodioideae) and four species of Suaeda (subf. Suaedoideae) were chosen as outgroups. Results show that the annual genus Salicornia is a sister group to the perennial genera Sarcocornia, Arthrocnemum and Halocnemum. Moreover, the phylogenetic analysis based on ITS results distinguished two groups of Salicornia species which fitted with ploidy level: one group consisted of diploid species, and the second of tetraploid ones. Sarcocornia and Arthrocnemum are shown to be closely related, even though the species investigated here exhibited an evident distance between their ITS sequences. On the basis of our results, these two genera should be united. Bienertia (already separated as Bienertieae) was confirmed as probable outgroup to the subf. Salicornioideae, while Kalidium (subf. Salicornioideae, tribe Halopeplideae) was an outgroup to the rest of the Salicornioideae (tribe Salicornieae). The group Allenrolfea plus Halocnemum was the most basal of the tribe Salicornieae amongst those investigated in this study. The two samples of Halocnemum strobilaceum used in this work displayed numerous changes (transitions and transversions) in their respective sequences, probably related to their morphological and chorological differentiation. On the basis of our analysis, the most probable basal chromosome number for Salicornieae appears to be 2n = 18. The same number would also be the base number for the annual genus Salicornia and the perennial Arthrocnemum ( + Sarcocornia), with polyploidy arising independently in the two groups.     

Substructure of the glomerular slit diaphragm in freeze-fractured normal rat kidney

In the renal glomerulus, the narrow slits between adjacent epithelial podocytes are bridged by a diaphragm (2, 8, 11). In rat and mouse kidneys fixed by perfusion with tannic acid and glutaraldehyde (TAG), it has recently been discovered that this diaphragm has a highly ordered, isoporous substructure (9). It consists of a regular array of alternating cross bridges extending from the podocyte plasma membranes to a centrally running filament. This zipperlike pattern results in two rows of rectangular pores, approximately 40 X 140 A in cross section, dimensions consistent with the proposed role of the diaphragm as an important filtration barrier to plasma proteins (6). In the present study, we found in freeze-cleaved and in freeze-etched normal rat glomeruli that the surface of the slit diaphragm has an appearance conforming to the pattern found in sectioned material.     

Statistical deconvolution of enthalpic energetic contributions to MHC-peptide binding affinity

Background  

MHC Class I molecules present antigenic peptides to cytotoxic T cells, which forms an integral part of the adaptive immune response. Peptides are bound within a groove formed by the MHC heavy chain. Previous approaches to MHC Class I-peptide binding prediction have largely concentrated on the peptide anchor residues located at the P2 and C-terminus positions.     

Erratum to: Seroprevalence of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in Danish horses

Background  

Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses.