Genome of the host-cell transforming parasite Theileria annulata compared with T. parva

Theileria annulata and T. parva are closely related protozoan parasites that cause lymphoproliferative diseases of cattle. We sequenced the genome of T. annulata and compared it with that of T. parva to understand the mechanisms underlying transformation and tropism. Despite high conservation of gene sequences and synteny, the analysis reveals unequally expanded gene families and species-specific genes. We also identify divergent families of putative secreted polypeptides that may reduce immune recognition, candidate regulators of host-cell transformation, and a Theileria-specific protein domain [frequently associated in Theileria (FAINT)] present in a large number of secreted proteins.     

Evaluation of a TaqMan real-time PCR for the detection of Theileria parva in buffalo and cattle

A real-time PCR assay based on TaqMan probe chemistry was developed for the detection of Theileria parva DNA in blood samples. It uses a Theileria genus-specific PCR primer set and a T. parva-specific probe to amplify and hybridize with a species-specific part of the 18S rRNA gene of the parasite. The test was evaluated using positive and negative reference blood samples and shown to be specific for T. parva. Analytical sensitivity was determined by testing a dilution series of T. parva positive blood. It was shown to be able to detect parasitaemia as low as 2 × 10(-6)%. The Taqman assay results were also compared with that obtained with the real-time hybridization probe PCR assay, which is currently employed as the official test for the diagnosis of T. parva infections in buffalo and cattle and was shown to be equally sensitive. A panel of 1164 field samples was screened using both assays and 164 samples tested positive in both tests, indicating a good correlation.     

Electrical recordings from meningioma cells during cytolytic action of antibody and complement

Resting membrane potential and total cell resistance of human meningioma cells in tissue culture have been measured with fine microelectrodes. Addition of either antiserum inactivated with heat or control serum from normal rabbits produced small depolarizations (2 to 4 millivolts) with no discernible ( 5 percent) change in resistance. Addition of antiserums with complement, however, produced larger depolarizations and decreases in resistance before any changes in cell morphology were visible with light microscopy; as cytoplasmic swelling progressed, membrane potential dropped close to zero, and resistance decreased five- to tenfold. The electrical recording technique may be useful in the study of sublethal as well as lethal damage to immune cells and, in particular, may permit temporal resolution of damaging events and repair mechanisms in a single cell.     

Effectiveness of acoustic cameras as tools for assessing biogenic structures formed by Sabellaria in highly turbid environments

1. Accurately mapping the extent and status of biogenic reefs formed by polychaete worms of the genus Sabellaria is of conservation importance given their protected status across Europe.
2. Traditionally, side‐scan sonar (SSS) combined with ground‐truthing in the form of seabed photography and videography has been widely accepted as the most suitable approach for mapping these reefs in the subtidal zone. In highly turbid environments visibility at the seabed can be near zero, however, rendering optical‐based ground‐truthing redundant. Consequently, the true distribution and status of Sabellaria reefs in some shallow subtidal areas around the UK remains unclear despite their designation as Annex‐I features of several Special Areas of Conservation (SACs) under the Habitats Directive.
3. Acoustic camera imagery (ACI) collected using acoustic cameras in two deployment configurations matched well with the backscatter signatures of seabed features in corresponding SSS data. The ACI was of suitable resolution for visualizing Sabellaria colony structures, allowing for their Annex‐I ‘reef’ defining attributes (extent, patchiness, and elevation) to be assessed. Colony formation ‘type’ was also distinguishable in the ACI, although confidence in differentiating between low‐lying Sabellaria formations and surrounding substrates was low, particularly when using a pole‐mounted configuration.
4. This study provides a proof of concept for using acoustic cameras as tools for ground‐truthing SSS interpretation and assessing the status of Sabellaria bioconstructions in low‐visibility environments. Further development of this approach and incorporating it into statutory monitoring programmes could improve the management of the reef habitats in subtidal areas of the Severn Estuary and other highly turbid environments.

     

IDENTIFICATION OF ARACHNOID CYSTS IN THE QUADRIGEMINAL CISTERN USING ULTRASONOGRAPHY

The ultrasonographic findings in three small breed dogs with intracranial arachnoid cysts are described. Ultrasound images were obtained via the foramen magnum, temporal window and persistent bregmatic fontanelle (when possible). In transverse, dorsal and sagittal transcranial ultrasound images there was marked dilation of the lateral ventricles and a well-defined, oval to triangular-shaped anechoic area between the caudal aspect of the occipital lobes, dorsal to the midbrain, and rostral to the cerebellum. These findings were consistent with a diagnosis of concurrent hydrocephalus and an arachnoid cyst within the quadrigeminal cistern.