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1.  Unexpected Brucella suis Biovar 2 Infection in a Dairy Cow, Belgium 
Emerging Infectious Diseases  2013;19(12):2053-2054.
doi:10.3201/eid1912.130506
PMCID: PMC3840864  PMID: 24274041
Brucella suis biovar 2; Brucella suis; brucellosis; cattle; wild boar; hunting; biosecurity; cow; Belgium; bacteria; bovine
2.  In Vitro and In Vivo Infectious Potential of Coxiella burnetii: A Study on Belgian Livestock Isolates 
PLoS ONE  2013;8(6):e67622.
Q-fever is a zoonosis caused by the gram-negative obligate intracellular pathogen Coxiella burnetii. Since its discovery, and particularly following the recent outbreaks in the Netherlands, C. burnetii appeared as a clear public health concern. In the present study, the infectious potential displayed by goat and cattle isolates of C. burnetii was compared to a reference strain (Nine Mile) using both in vitro (human HeLa and bovine macrophage cells) and in vivo (BALB/c mice) models. The isolates had distant genomic profiles with one - the goat isolate - being identical to the predominant strain circulating in the Netherlands during the 2007–2010 outbreaks. Infective doses were established with ethidium monoazide-PCR for the first time here applied to C. burnetii. This method allowed for the preparation of reproducible and characterized inocula thanks to its capacity to discriminate between live and dead cells. Globally, the proliferative capacity of the Nine Mile strain in cell lines and mice was higher compared to the newly isolated field strains. In vitro, the bovine C. burnetii isolate multiplied faster in a bovine macrophage cell line, an observation tentatively explained by the preferential specificity of this strain for allogeneic host cells. In the BALB/c mouse model, however, the goat and bovine isolates multiplied at about the same rate indicating no peculiar hypervirulent behavior in this animal model.
doi:10.1371/journal.pone.0067622
PMCID: PMC3695903  PMID: 23840751
3.  Buffer substitution in malaria rapid diagnostic tests causes false-positive results 
Malaria Journal  2010;9:215.
Background
Malaria rapid diagnostic tests (RDTs) are kits that generally include 20 to 25 test strips or cassettes, but only a single buffer vial. In field settings, laboratory staff occasionally uses saline, distilled water (liquids for parenteral drugs dilution) or tap water as substitutes for the RDT kit's buffer to compensate for the loss of a diluent bottle. The present study assessed the effect of buffer substitution on the RDT results.
Methods
Twenty-seven RDT brands were run with EDTA-blood samples of five malaria-free subjects, who were negative for rheumatoid factor and antinuclear antibodies. Saline, distilled water and tap water were used as substitute liquids. RDTs were also run with distilled water, without adding blood. Results were compared to those obtained with the RDT kit's buffer and Plasmodium positive samples.
Results
Only eight cassettes (in four RDT brands) showed no control line and were considered invalid. Visible test lines occurred for at least one malaria-free sample and one of the substitutes in 20/27 (74%) RDT brands (saline: n = 16; distilled water: n = 17; and tap water: n = 20), and in 15 RDTs which were run with distilled water only. They occurred for all Plasmodium antigens and RDT formats (two-, three- and four-band RDTs). Clearance of the background of the strip was excellent except for saline. The aspects (colour, intensity and crispness) of the control and the false-positive test lines were similar to those obtained with the RDT kits' buffer and Plasmodium positive samples.
Conclusion
Replacement of the RDT kit's dedicated buffer by saline, distilled water and tap water can cause false-positive test results.
doi:10.1186/1475-2875-9-215
PMCID: PMC3224932  PMID: 20650003
4.  Assessment of the prozone effect in malaria rapid diagnostic tests 
Malaria Journal  2009;8:271.
Background
The prozone effect (or high doses-hook phenomenon) consists of false-negative or false-low results in immunological tests, due to an excess of either antigens or antibodies. Although frequently cited as a cause of false-negative results in malaria rapid diagnostic tests (RDTs), especially at high parasite densities of Plasmodium falciparum, it has been poorly documented. In this study, a panel of malaria RDTs was challenged with clinical samples with P. falciparum hyperparasitaemia (> 5% infected red blood cells).
Methods
Twenty-two RDT brands were tested with seven samples, both undiluted and upon 10 ×, 50 × and 100 × dilutions in NaCl 0.9%. The P. falciparum targets included histidine-rich protein-2 (HRP-2, n = 17) and P. falciparum-specific parasite lactate dehydrogenase (Pf-pLDH, n = 5). Test lines intensities were recorded in the following categories: negative, faint, weak, medium or strong. The prozone effect was defined as an increase in test line intensity of at least one category after dilution, if observed upon duplicate testing and by two readers.
Results
Sixteen of the 17 HRP-2 based RDTs were affected by prozone: the prozone effect was observed in at least one RDT sample/brand combination for 16/17 HRP-2 based RDTs in 6/7 samples, but not for any of the Pf-pLDH tests. The HRP-2 line intensities of the undiluted sample/brand combinations with prozone effect (n = 51) included a single negative (1.9%) and 29 faint and weak readings (56.9%). The other target lens (P. vivax-pLDH, pan-specific pLDH and aldolase) did not show a prozone effect.
Conclusion
This study confirms the prozone effect as a cause of false-negative HRP-2 RDTs in samples with hyperparasitaemia.
doi:10.1186/1475-2875-8-271
PMCID: PMC2789093  PMID: 19948018
5.  A New E6/P63 Pathway, Together with a Strong E7/E2F Mitotic Pathway, Modulates the Transcriptome in Cervical Cancer Cells▿  
Journal of Virology  2007;81(17):9368-9376.
Cervical carcinoma is associated with certain types of human papillomaviruses expressing the E6 and E7 oncogenes, which are involved in carcinogenesis through their interactions with the p53 and pRB pathways, respectively. A critical event on the path to malignant transformation is often manifested by the loss of expression of the viral E2 transcription factor due to the integration into the host genome of the viral DNA. Using microarrays, we have previously shown that reintroduction of a functional E2 in the HeLa cervical carcinoma cell line activates a cluster of p53 target genes while at the same time severely repressing a group of E2F target genes. In the present study, using new high-density microarrays containing more than 22,000 human cDNA sequences, we identified a novel p63 pathway among E2-activated genes and 38 new mitotic genes repressed by E2. We then sought to determine the pathways through which these genes were modulated and used an approach that relies on small interfering RNA to demonstrate that the p63 target genes were activated through silencing of the E6/E6AP pathway while the mitotic genes were mainly repressed through E7 silencing. Importantly, a subset of the mitotic genes was shown to be significantly induced in biopsies of stage IV cervical cancers, which points to a prominent E7 pathway in cervical carcinoma.
doi:10.1128/JVI.00427-07
PMCID: PMC1951466  PMID: 17582001

Results 1-5 (5)