Feline herpesvirus 1 and feline calicivirus infections in a heterogeneous cat population of a rescue shelter.

Feline herpesvirus 1 (FeHV-1) and feline calicivirus (FCV), associated with upper respiratory tract disease, are highly prevalent in cats worldwide. With the aim to investigate the importance of feline respiratory viruses in a heterogeneous population of cats, samples were taken in a rescue shelter in Liege, Belgium, between March 2005 and August 2006. Reverse transcription polymerase chain reaction (RT-PCR) and polymerase chain reaction (PCR) were performed to diagnose FCV and FeHV-1 infection in the sampled cats. The prevalence rate (33.1%) was higher for FCV than for FeHV-1 (20.1%) whereas prevalence rate of co-infection with both viruses was 10%. Gingivitis was more common in FCV infections (odds ratio (OR)=2.83) whereas respiratory signs were more often observed with FeHV-1 infections. The average age was significantly higher in FCV positive cats (38 months) than in FeHV-1 positive cats (29.9 months). The second and the fourth quarters of the year and the two first quarters were significantly more at risk than the others in the case of FeHV-1 and FCV infection, respectively. Age was found to be a confounding factor. High prevalence of both infections strengthens the importance of applying hygienic and preventive measures in rescue shelters where cats with an unknown status of vaccination are introduced.Peer reviewe

A SYBR Green RT-PCR assay in single tube to detect human and bovine noroviruses and control for inhibition

BACKGROUND: Noroviruses are single-stranded RNA viruses belonging to the family Caliciviridae. They are a major cause of epidemic and sporadic gastroenteritis in humans and clinical signs and lesions of gastroenteritis were reported in bovines. Due to their genetic proximity, potential zoonotic transmission or animal reservoir can be hypothesized for noroviruses. RT-PCR has become the "gold standard" for the detection of noroviruses in faecal and environmental samples. With such samples, the control for inhibition of the reaction during amplification and detection is crucial to avoid false negative results, which might otherwise not be detected. The aim of the reported method is to detect, with a SYBR Green technology, a broad range of noroviruses with a control for inhibition. RESULTS: A SYBR Green real-time RT-PCR assay was developed making use of a foreign internal RNA control added in the same tube. This assay is able to detect human and bovine noroviruses belonging to genogroups I, II and III and to distinguish between norovirus and internal control amplicons using melting curve analysis. A 10-fold dilution of samples appears to be the method of choice to remove inhibition. This assay was validated with human and bovine stool samples previously tested for norovirus by conventional RT-PCR. CONCLUSION: This SYBR Green real-time RT-PCR assay allows the detection of the most important human and bovine noroviruses in the same assay, and avoids false negative results making use of an internal control. Melting curves allow the discrimination between the internal control and norovirus amplicons. It gives preliminary information about the species of origin. The sensitivity of the developed assay is higher than conventional RT-PCR and a 10-fold dilution of samples showed a better efficiency and reproducibility to remove RT-PCR inhibition than addition of bovine serum albumin

Bluetongue in Captive Yaks

In August 2006, several Northern European countries including Belgium reported their first cases of bluetongue (BT). Surprisingly, it was the first time that BT was diagnosed so far in the northern hemisphere (1). BT is a non contagious, arthropod borne animal disease. The causal virus belongs to the genus Orbivirus in the family Reoviridae. The genome of the bluetongue virus (BTV) consists of 10 segments of double-stranded RNA and 24 serotypes have been reported (2). Serotype 8 (BTV-8) was implied in the emergence in Belgium (3). All ruminant species are thought to be susceptible to BT (2) but lack of data remains for certain species. We report here laboratory confirmed clinical cases of BT in yaks

True versus False Parasite Interactions: A Robust Method to Take Risk Factors into Account and Its Application to Feline Viruses

International audienceBACKGROUND: Multiple infections are common in natural host populations and interspecific parasite interactions are therefore likely within a host individual. As they may seriously impact the circulation of certain parasites and the emergence and management of infectious diseases, their study is essential. In the field, detecting parasite interactions is rendered difficult by the fact that a large number of co-infected individuals may also be observed when two parasites share common risk factors. To correct for these "false interactions", methods accounting for parasite risk factors must be used. METHODOLOGY/PRINCIPAL FINDINGS: In the present paper we propose such a method for presence-absence data (i.e., serology). Our method enables the calculation of the expected frequencies of single and double infected individuals under the independence hypothesis, before comparing them to the observed ones using the chi-square statistic. The method is termed "the corrected chi-square." Its robustness was compared to a pre-existing method based on logistic regression and the corrected chi-square proved to be much more robust for small sample sizes. Since the logistic regression approach is easier to implement, we propose as a rule of thumb to use the latter when the ratio between the sample size and the number of parameters is above ten. Applied to serological data for four viruses infecting cats, the approach revealed pairwise interactions between the Feline Herpesvirus, Parvovirus and Calicivirus, whereas the infection by FIV, the feline equivalent of HIV, did not modify the risk of infection by any of these viruses. CONCLUSIONS/SIGNIFICANCE: This work therefore points out possible interactions that can be further investigated in experimental conditions and, by providing a user-friendly R program and a tutorial example, offers new opportunities for animal and human epidemiologists to detect interactions of interest in the field, a crucial step in the challenge of multiple infections

Isolation of Nucleoli from Ehrlich Ascites Tumor Cells and Dynamics of Nascent RNA within Isolated Nucleoli.

Here we describe a new, rapid method for isolating nucleoli from Ehrlich tumor cells that preserves their morphological integrity and high transcriptional activity. Until now, methods for isolation of nucleoli were generally assumed to empty one of their three main compartments, the fibrillar center, of its contents. This new method consists of sonicating cells in an isotonic medium containing MgSO(4), spermidine, and spermine, followed by separation of nucleoli through a Percoll density gradient. Using the nonisotopic approach of labelling with BrUTP, we have further investigated the dynamics of nascent ribosomal RNAs (rRNAs) within morphologically intact isolated nucleoli at the electron microscope level. We show that ribosomal transcripts are elongated in the cortex of the fibrillar center and then enter the surrounding dense fibrillar component

Assessment of the analytical performance and the sensitivity of serum free light chains immunoassay in patients with monoclonal gammopathy

Objectives: A new immunoassay which quantifies Kappa, Lambda free light chains (FLC) and a ratio of Kappa to Lambda FLC has been reported to be sensitive for detecting a variety of FLC diseases. We assessed the analytical criteria and the diagnostic performance of this immunoassay in patients who present a monoclonal gammopathy. Design and methods: Quantification of FLC, serum protein electrophoresis (SPE) and immunofixation (IFE) were performed on patients who present a monoclonal gammopathy of undetermined significance (MGUS), an intact immunoglobulin multiple myeloma (IIMM) or a light chain multiple myeloma (LCMM). Results: The monoclonal component was identified by IFE in the sera of all patients. Based on the diagnostic reference range, the ratio of Kappa to Lambda FLC was abnormal in 25% of the tested population, compared to 94% for SPE in MGUS patients. For IIMM and LCMM, the FLC ratio was abnormal in 70% and 100% of the population, compared to 85% and 40% for SPE, respectively. Conclusion: SPE and IFE have a higher sensitivity for identifying MGUS and IIMM. © 2006 The Canadian Society of Clinical Chemists.SCOPUS: ar.jinfo:eu-repo/semantics/publishe