The majority of pathogens that cause high host mortalities are capable of infecting more than 1 host species. One characteristic of pathogens, which enables infection of multiple hosts, is the ...existence of free-living infectious stages, e.g., zoospores that are produced in vast numbers. Understanding the influence of environmental factors, particularly temperature, on the production and survival of these free-living stages is key to predicting future spread and emergence of disease. The rosette agent, Sphaerothecum destruens, is a significant multi-host intracellular fish parasite, with an obligate intracellular spore stage and a free-living (extracellular), potentially infectious, zoospore stage. It has caused high mortalities in endangered and commercially important fish species. Here we investigate the influence of temperature on S. destruens zoospore production and longevity. Our results indicate a wide temperature tolerance of the spore and zooflagellate stage with later onset and longer lifespan of zoospores at lower temperatures. This has important implications for the environmental persistence of S. destruens and provides additional information on the pathogen's life cycle with direct implications for S. destruens risk assessment.
Sphaerothecum destruens is a significant intracellular parasite of fish which has caused disease and mortalities in cultured north American Chinook salmon Oncorhynchus tshawytscha and Atlantic salmon ...Salmo salar. Several hosts for S. destruens have been identified within the Salmonidae family, and the histopathology of the infection can differ between hosts. Recently, S. destruens has been associated with the most invasive cyprinid species in Europe, topmouth gudgeon Pseudorasbora parva. Accurate disease identification based on thorough descriptions of clinical signs and histopathology in this new range of hosts is thus paramount to support further epizootiological studies. In this study, the associated histopathology of S. destruens infection is described along with its pathogenesis in the endangered cyprinid sunbleak Leucaspius delineatus. Histological examination of 100 L. delineatus in a wild population in the south of England revealed the presence of S. destruens infections, with a prevalence of 5% with S. destruens, suggesting an over-dispersed distribution within the L. delineatus sample. Clinical signs of the infection were absent, but histological examination revealed the presence of both disseminated and nodular lesions in several organs.
Contrary to the relatively common benign bone tumours and tumour-like lesions, bone sarcomas are rare malignancies with an incidence of 0.8 new cases per 100 000 persons per year. The most common ...primary malignant bone tumour is osteosarcoma, followed by chondrosarcoma and Ewing sarcoma. Osteosarcomas and Ewing sarcomas occur predominantly in children, adolescents and young adults, while chondrosarcomas primarily affect older patients. Most of the tumours are located in the extremities and the pelvis and in about 90% of the cases the surgical treatment can be performed by means of a limb-sparing wide resection. An endoprosthetic or biological reconstruction of the resulting defect, depending on several patient- und tumour-related factors, is usually necessary. Apart from the surgical treatment, patients with osteosarcoma and Ewing sarcoma require a pre- and postoperative chemotherapy, while Ewing sarcoma patients often undergo radiation therapy as well. Regular follow-up examinations are required after the completion of treatment for the early detection and management of local and/or systemic recurrences as well as treatment-related complications. An extensive experience in the clinical and imaging features as well as the interdisciplinary treatment of these tumours is necessary for optimal patient care. Without it mistakes are often made, which can have grave consequences on the patients' prognosis and functional outcome. The centralised treatment of these patients in specialised sarcoma centres is therefore recommended.
Sphaerothecum destruens is an obligate intracellular parasite with the potential to cause high mortalities and spawning inhibition in the endangered cyprinid Leucaspius delineatus. We investigated ...the influence of L. delineatus's reproductive state on the prevalence and infection level of S. destruens. A novel real time quantitative polymerarse chain reaction (qPCR) was developed to determine S. destruens' prevalence and infection level. These parameters were quantified and compared in reproductive and non-reproductive L. delineatus. The detection limit of the S. destruens specific qPCR was determined to be 1 pg of purified S. destruens genomic DNA. Following cohabitation in the lab, reproductive L. delineatus had a significantly higher S. destruens prevalence (P<0.05) and infection levels (P<0.01) compared to non-reproductive L. delineatus. S. destruens prevalence was 19% (n=40) in non-reproductive L. delineatus and 41% (n=32) in reproductive L. delineatus. However, there was no difference in S. destruens prevalence in reproductive and non-reproductive fish under field conditions. Mean infection levels were 18 and 99 pg S. destruens DNA per 250 ng L. delineatus DNA for non-reproductive and reproductive L. delineatus respectively. The present work indicates that S. destruens infection in L. delineatus can be influenced by the latter's reproductive state and provides further support for the potential adverse impact of S. destruens on the conservation of L. delineatus populations.
The efficiency of individual genetic tagging was determined by using passive integrated transponders (PIT) as a comparative conventional tagging method. Fifty‐five common dace Leuciscus leuciscus ...were captured in the wild, PIT tagged and fin clipped (for DNA analysis). Thirty fish were recaptured on three occasions and tissue samples were collected. Using 18 microsatellite loci, 79–94% of the recaptures were correctly assigned. Experience with scoring L. leuciscus microsatellites led to more individuals correctly assigned. Allowing matches that differed by one or two alleles resulted in 100% of all recaptures successfully assigned irrespective of the observer. Reducing the set of loci to five to six loci appropriately selected did not affect the assignment rate, demonstrating that costs can be subsequently reduced. Despite their potential benefits, the application of genetic tags for teleosts has been limited. Here, it was demonstrated that genetic tagging could be applied, and a clear guideline (flowchart) is provided on how this method can be developed for teleosts and other organisms, with subsequent practical applications to ecology, evolutionary biology and conservation management.
We report the case of a 47-year-old patient with autosomal dominant polycystic kidney disease, who became symptomatic owing to a painful metastasis of a renal cell carcinoma. Abdominal sonography, ...multiphase CT and MRI were performed in order to localise and resect the primary tumour, but its identification was severely hampered owing to multiple renal cysts. In addition to standard MRI protocol, a spin-echo, single-shot echo planar diffusion-weighted imaging sequence was performed. The mean apparent diffusion coefficient (ADC) of renal cysts was 2.66±0.12 × 10(-3) mm(2) s(-1), 1.76±0.19 × 10(-3) mm(2) s(-1) of renal parenchyma in and 1.26±0.18 × 10(-3) mm(2) s(-1) of a suspicious soft-tissue mass at the midsection of the right kidney, indicating an area of higher cellularity. This value was significant lower than the ADC obtained for renal parenchyma (p<0.0001). Right-sided nephrectomy was performed and the pathological diagnosis of the suspicious lesion was clear cell renal carcinoma.
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