Use of a nested PCR-enzyme immunoassay with an internal control to detect Chlamydophila psittaci in turkeys

BACKGROUND: Laboratory diagnosis of Chlamydophila psittaci, an important turkey respiratory pathogen, is difficult. To facilitate the diagnosis, a nested PCR-enzyme immunoassay (PCR-EIA) was developed to detect the Cp. psittaci outer membrane protein A (ompA) gene in pharyngeal swabs. METHODS: The fluorescein-biotin labelled PCR products were immobilized on streptavidin-coated microtiter plates and detected with anti-fluorescein peroxidase conjugate and a colorimetric substrate. An internal inhibition control was included to rule out the presence of inhibitors of DNA amplification. The diagnostic value of the ompA nested PCR-EIA in comparison to cell culture and a 16S-rRNA based nested PCR was assessed in pharyngeal turkey swabs from 10 different farms experiencing respiratory disease. RESULTS: The sensitivity of the nested PCR-EIA was established at 0.1 infection forming units (IFU). Specificity was 100%. The ompA nested PCR-EIA was more sensitive than the 16S-rRNA based nested PCR and isolation, revealing 105 out of 200 (52.5%) positives against 13 and 74 for the latter two tests, respectively. Twenty-nine (23.8%) out of 122 ompA PCR-EIA negatives showed the presence of inhibitors of DNA amplification, although 27 of them became positive after diluting (1/10) the specimens in PCR buffer or after phenol-chloroform extraction and subsequent ethanol precipitation. CONCLUSION: The present study stresses the need for an internal control to confirm PCR true-negatives and demonstrates the high prevalence of chlamydiosis in Belgian turkeys and its potential zoonotic risk. The ompA nested PCR-EIA described here is a rapid, highly sensitive and specific diagnostic assay and will help to facilitate the diagnosis of Cp. psittaci infections in both poultry and man

HIV testing within general practices in Europe : A mixed-methods systematic review

Funding Information: This work was supported by IWT (Belgium) and the ANRS (France) through the framework of HIVERA JTC 2014. Publisher Copyright: © 2018 The Author(s).Background: Late diagnosis of HIV infection remains a key challenge in Europe. It is acknowledged that general practitioners (GPs) may contribute greatly to early case finding, yet there is evidence that many diagnostic opportunities are being missed. To further promote HIV testing in primary care and to increase the utility of available research, the existing evidence has been synthesised in a systematic review adhering to the PRISMA guidelines. Methods: The databases PubMed, Scopus and Embase were searched for the period 2006-2017. Two authors judged independently on the eligibility of studies. Through a mixed-methods systematic review of 29 studies, we provide a description of HIV testing in general practices in Europe, including barriers and facilitators. Results: The findings of the study show that although various approaches to target patients are used by GPs, most tests are still carried out based on the patient's request. Several barriers obstruct HIV testing in general practice. Included are a lack of communication skills on sexual health, lack of knowledge about HIV testing recommendations and epidemic specificities, difficulties with using the complete list of clinical HIV indicator diseases and lack of experience in delivering and communicating test results. The findings also suggest that the provision of specific training, practical tools and promotion programmes has an impact on the testing performance of GPs. Conclusions: GPs could have an increased role in provider-initiated HIV-testing for early case finding. To achieve this objective, solutions to the reported barriers should be identified and testing criteria adapted to primary healthcare defined. Providing guidance and training to better identify priority groups for HIV testing, as well as information on the HIV epidemic's characteristics, will be fundamental to increasing awareness and testing by GPs.publishersversionPeer reviewe

Walkway lengths for measuring walking speed in stroke rehabilitation

Author name used in this publication: Shamay S. M. Ng2011-2012 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Association of human herpesvirus 7 with cytomegalovirus disease in renal transplant recipients

Background. Recent studies have linked human herpesviruses 6 (HHV-6) and 7 (HHV-7) with posttransplant cytomegalovirus (CMV) disease. Methods. Thirty- seven renal transplant recipients were monitored weekly for CMV, HHV-6, and HHV-7 DNA and serological responses for 12 weeks after transplantation. Plasma CMV load and the occurrence of CMV disease was related to HHV-6 and -7 detection. Results. CMV disease was identified in 12 patients. In a logistic regression analysis, factors significantly associated with CMV disease were the detection of HHV-7 DNA in peripheral blood leucocytes and donor-recipient CMV serostatus. Patients with detectable HHV-7 DNA had significantly higher peak plasma CMV loads (P = 0.01). Conclusions. An association was found between HHV-7, but not HHV-6, DNA detection and CMV disease, suggesting a possible role of HHV-7 in its pathogenesis.link_to_subscribed_fulltex

Association of tumour necrosis factor aplha and interleukin 6 levels with cytomegalovirus DNA detection and disease after renal transplantation

Cytokines such as tumour necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) are thought to be important in the pathogenesis of post-transplant cytomegalovirus (CMV) disease. CMV infection increases the production of TNF-α and IL-6. Conversely, TNF-α switches on the replication of CMV. To study the association of these two cytokines with CMV activity and disease, TNF-α and IL-6 levels were assayed in plasma samples taken serially from three groups of renal transplant recipients. Group A (n = 12) had CMV disease and syndrome; Group B (n = 11) had detectable CMV DNA in plasma or peripheral blood leucocytes without disease, i.e., presumed asymptomatic CMV infection, and Group C (n = 11) had no detectable CMV DNA nor disease. The median peak TNF-α levels in patients with CMV disease (Group A) were significantly higher than that in Group B or Group C (P  10,000 copies/ml). IL-6 levels above 15 pg/ml were significantly associated with CMV DNA detection, but not with CMV disease or elevated CMV load. High levels of TNF-α or IL-6 were not associated with CMV donor/recipient serostatus, HHV-6 or HHV-7 DNA detection, immunosuppressive regimen or rejection episodes. The role of TNF-α in the pathogenesis of CMV disease deserves further investigation. J. Med. Virol. 64:29–34, 2001. © 2001 Wiley-Liss, Inc

Prevalence of tick-borne encephalitis virus in Ixodes ricinus ticks in Finland

Approximately 20 cases of tick-borne encephalitis (TBE) occur annually in Finland. The known endemic areas are situated mainly in the archipelago and coastal regions of Finland, with highest incidence in Åland islands. Ixodes ricinus panels collected in 1996-1997 from two endemic areas were screened for the presence of RNA. Two distinct RT-PCR methods were applied, and were shown to have an approximate detection limit of 10 focus forming doses (FFD)/100 μl. One out of 20 pools (a total of 139 ticks) from Helsinki Isosaari Island and one out of 48 pools (a total of 450 ticks) from Åland were positive with both methods, whereas the remaining pools were negative. The observed overall frequency (0.34%) in ticks in endemic areas of Finland, was similar to the low incidence found by virus isolation in mice in the 1960s (0.5%). Viral RNA was detectable in a diluted sample representing 0.005% of a positive pool often nymphs suggesting that the viral RNA load within an infected tick pool was approximately equivalent to 20,000-200,000 FFD. Sequence analysis did not show geographical clustering of the Finnish strains, suggesting an independent emergence of different TBE foci from the south. TBE virus RNA positive ticks were not found in I. ricinus panels consisting of 130 pools (726 ticks) from Helsinki city parks or 41 pools (197 ticks) from Võrmsi Island in Estonia. © 2001 Wiley-Liss, Inc.link_to_subscribed_fulltex

Assessing the walking speed of older adults: The influence of walkway length

OBJECTIVE: The aim of this study was to investigate the effect of walkway length (5, 8, or 10 m) on measurements of comfortable and maximum walking speed in healthy older adults. DESIGN: In this cross-sectional study at a university-based rehabilitation center, 25 healthy older adults (mean age, 60.3 ± 8.3 yrs) participated in timed walking at both comfortable and maximum speeds with different walkway lengths (5-, 8-, and 10-m walkway distances) measured by a stopwatch. RESULTS: Walkway length did not affect either comfortable walking speed (P = 0.319) or maximum walking speed (P = 0.568). For all walkway lengths, comfortable speed was significantly different from maximum speed (P < 0.001). CONCLUSIONS: Different walkway lengths (5, 8, and 10 m) do not affect both comfortable and maximum walking speed and can yield consistent results in measuring gait speed clinically. A 5-m walkway with standardized 2-m acceleration and 2-m deceleration distances is recommended because it occupies less space and imposes less stress on the healthy older adults.link_to_subscribed_fulltex