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Przedstawiono analizą struktury sprzedaży wody mineralnej na rynku w Polsce w 2001 r.
Przedstawiono analizę rynku napojów bezalkoholowych w 2001 r. i strukturę sprzedaży poszczególnych kategorii - napojów gazowanych, niegazowanych i wód mineralnych. Omówiono strukturę sprzedaży pod względem smaku i użytych rodzajów opakowań.
110 blood samples from clinically healthy mares of English breed, half-blood and the Wielkopolska race were tested for the presence of EHV-1 and EHV-2 using nested PCR. 15 samples were EHV-1-positive, 24 samples were EHV-2-positive, whereas only 4 samples were both EHV-1 and EHV-2 positive. The virus was isolated from PBLs in equine dermal cell cultures by co-cultivation or by culture inoculation with cell lysates derived from PBLs. A total of 14 strains were isolated from EHV-2 and EHV-1/EHV-2-positive samples. However, all of them were identified by nPCR as being type 2. Since no EHV-1 was isolated, even from dually infected leukocytes, it was concluded that the presence of EHV-2 does not stimulate in-vitro isolation of EHV-1 from infected leukocytes. It is tempting to speculate that such stimulatory effects in-vivo may involve EHV-2-induced immunosupression. Despite any possible mechanism of EHV-1 stimulation, it seems that EHV-2 does not play a significant role in the epidemiology of EHV-1-caused miscarriages in horses since mixed infections are rather rare.
The aim of the study was to investigate the influence of equine herpesvirus type 1 (EHV-1) infection on actin cytoskeleton in ED (equine dermal). Cells in vitro.ED cells were infected with a strain of Jan-E of EHV-1, fixed and stained for the presence of actin and virus antigen. Results were evaluated by confocal microscopy. The assembly of the actin cytoskeleton was heavily disturbed. In order to affirm whether changes in cytoskeleton of EHV-1 infected cells depend on the type of cells, we infected Vero cell culture with 2 different standard strains of EHV-1 - Rac-H, AIV - and Jan-E isolated from an aborted fetus. Unfortunately, the infection of Vero cells with the strain Jan-E of EHV-1 failed because this strain was not adapted to the heterogeneous cell line. Only strain Rac-H and AIV can replicate in Vero cells, which was determined through the application of PCR.
The nested PCR technique (Borchers and Slater, 1993) was applied for the diagnosis of EHV-1 infections. DNA samples were isolated from livers of miscarried fetuses or dead foals. After amplification we detected EHV-1 specific sequences in 9 out of 15 fetuses and in 2 out of 6 foals. PCR results were compared to results of routinely performed immunofluorescent detection of viral antigen in cryosections of tissues. Six tested fetuses were FAT-positive, 7 FAT-negative and 2 were questionable. One FAT-negative fetus and two questionable were PCR-positive. All foals were FAT-negative. We have demonstrated that PCR is more sensitive than FAT and allows verification of inconclusive results of antigen detection. PCR is also suitable for detection of EHV-1 specific sequences in archival samples frozen up to 3 years.
In previous experiments, we have demonstrated that the presence of equine herpesvirus 2 (EHV-2) enhanced plaque formation in cell cultures infected with equine herpesvirus type 1. To determine whether a specific region of the EHV-2 genome is responsible for this effect, we have constructed a library of Bam HI fragments of the EHV-2 genome ligated into pcDNA plasmid. Equine dermal (ED) cell cultures were subsequently transfected with the constructs, passaged 5 times, tested for the presence of the plasmids and infected with EHV-1 at MOI=0.01. Only in cultures transfected with the pcDNA/Bam HI[G]construct, designated Δ2/4, the mean number of plaques at 24 hrs p.i. was approximately 10 times higher than in non-transfected controls. Virus titers in culture supernatants as well as in freeze-thawed cells were 4- and 5-fold higher, respectively, than in non-transfected cultures. These differences were observed only at 24 hrs p.i. At 48 hrs p.i. cultures were completely destroyed and, surprisingly, the virus titer was slightly lower in the supernatant of transfected cells. However, the titer of EHV-1 in freeze-thawed culture was exactly the same as in the control. These results suggest that the presence of Bam HI[G] fragment of the EHV-2 genome stimulates (accelerates?) plaque formation only at earlier stages of infection but does not influence the total yield of EHV-1 at 48 hrs p.i. The exact mechanism of this stimulation remains unclear and further experiments are necessary to determine the role of putative EHV-2 proteins encoded by Bam HI [G] fragment of the EHV-genome.
Equine herpesvirus type 1 (EHV-1) is one of the major horse diseases, causing considerable worldwide losses. A variety of techniques, including nested PCR, have been used to diagnose EHV-1 infections. In this paper, a real-time PCR assay that uses non-specific SYBR Green I® fluorochrome for the detection of EHV-1 DNA is described. This method does not require post-amplification manipulations, thereby reducing the risk of cross-contamination. The assay was sensitive enough to detect EHV-1 sequences in neuronal cell cultures and also different clinical samples. The technique is specific: it was not reactive with other herpesviruses or opportunistic bacterial pathogens such as Escherichia coli, Staphylococcus epidermidis and Enterococcus faecium. In comparison to virus isolation or the nested PCR used previously, the test was more sensitive and should be useful for the common diagnosis based on its specificity and rapidity.
Equine herpesvirus type 1 (EHV-1) is one of the major viral agents causing diseases in horses common worldwide. A variety of techniques, including PCR, have been used to diagnose EHV-1 infections. In this paper, an attempt of real-time PCR has been described, which uses specific fluorochrome-labeled TaqMan probes for detection of viral DNA. This method does not require post-amplification manipulations, thereby reducing the risk of cross-contamination. The assay was sensitive enough to detect EHV-1 sequences in different clinical samples, as well in mice neuronal cell cultures. The technique was also very specific – there was no cross reaction with other human and equine herpesviruses. Compared to previously used nested PCR technique, the test was more sensitive and should be useful for the common diagnosis based on its specificity and rapidity.
Equid herpesvirus type 1 (EHV-1) is a prevalent causative agent of equine diseases worldwide. After primary replication in the respiratory epithelium the virus disseminates systemically through a peripheral blood mononuclear cell (PBMC)-associated viraemia. EHV-1 is the only alphaherpes-virus known so far which is capable of establishing latent infection not only in neurons but also in immune system cells (mainly in lymphocytes and macrophages). Since leukocytes are not the target cells for viral replication but are used to transport EHV-1 to the internal organs, the question remains how the virus avoids the immune response and whether it could potentially be associated with virus-induced cytoskeletal rearrangements. Therefore, the aim of this study was to investigate the progress of EHV-1 replication in leukocytes stimulated by phytohemagglutinin and the impact of EHV-1 infection on the actin cytoskeleton. Using the real-time PCR method we evaluated the quantity of viral DNA from samples collected at indicated time points post infection. In order to examine possible changes in actin cytoskeleton organization due to EHV-1 infection, we performed immunofluorescent staining using TRITC-phalloidin conjugate. The results showed that EHV-1 replicates in leukocytes at a restricted level but with the accompaniment of chromatin degradation. Simultaneously, infection with EHV-1 caused disruption of the actin cytoskeleton; this was particularly apparent in further stages of infection. Disruption of the actin cytoskeleton may lead to the limited release of the virus from the cells, but may be also beneficial for the virus, since at the same time it potentially impairs the immune function of leukocytes.
Real-time cell electronic sensing (RT-CES) based on impedance measurements is an emerging technology for analyzing the status of cells in vitro. It allows label-free, real time monitoring of the biological status of cells. The present study was designed to assess dynamic data on the cell processes during equine herpesvirus type 1 (EHV-1) infection of ED (equine dermal) cells and primary murine neuronal cell culture. We have demonstrated that the xCELLigence system with dynamic monitoring can be used as a rapid diagnostic tool both to analyze cellular behavior and to investigate the effect of viral infection.
Equine herpesvirus type 1 (EHV-1) causes respiratory infections, abortion and neurological disorders in horses. Molecular epidemiology studies have demonstrated that a single-point mutation in DNA polymerase gene, resulting in an amino acid variation (N752/D752), is significantly associated with the neuropathogenic potential of EHV-1 strains. The aim of the study was to elucidate if there are any differences between neuropathogenic (EHV-1 26) and non-neuropathogenic (Jan-E and Rac-H) EHV-1 strains in their ability to infect neuronal cells. For the tested EHV-1 strains, cytopathic effect (CPE) was manifested by changed morphology of cells, destruction of actin cytoskeleton and nuclei degeneration, which led to focal degeneration. Moreover, EHV-1 26 strain caused fusion of the infected cells to form syncytia in culture. Real-time PCR analysis demonstrated that both neuropathogenic and non-neuropathogenic EHV-1 strains replicated in neurons and ED cells (equine dermal cell line) at a similar level. We can assume that a point mutation in the EHV-1 polymerase does not affect viral replication in this cell type.
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