Antigenic cross-reactivity between severe acute respiratory syndrome-associated coronavirus and human coronaviruses 229E and OC43

Cross-reactivity between antibodies to different human coronaviruses (HCoVs) has not been systematically studied. By use of Western blot analysis, indirect immunofluorescence assay (IFA), and enzyme-linked immunosorbent assay (ELISA), antigenic cross-reactivity between severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) and 2 HCoVs (229E and OC43) was demonstrated in immunized animals and human serum. In 5 of 11 and 10 of 11 patients with SARS, paired serum samples showed a ≥4-fold increase in antibody titers against HCoV-229E and HCoV-OC43, respectively, by IFA. Overall, serum samples from convalescent patients who had SARS had a 1-way cross-reactivity with the 2 known HCoVs. Antigens of SARS-CoV and HCoV-OC43 were more cross-reactive than were those of SARS-CoV and HCoV-229E. © 2005 by the Infectious Diseases Society of America. All rights reserved.published_or_final_versio

Direct detection of Mycobacterium tuberculosis in clinical specimens using single-tube biotinylated nested polymerase chain reaction-enzyme linked immunoassay (PCR-ELISA)

A biotinylated single-tube nested polymerase chain reaction (PCR) assay with microwell hybridization assay (bPCR-ELISA) was developed for detection of Mycobacterium tuberculosis in clinical specimens. A total of 659 specimens (601 respiratory specimens and 58 nonrespiratory specimens) were collected for evaluation using three DNA amplification techniques: newly designed bPCR-ELISA, in-house single-tube nested PCR for IS6110 gene sequence (nPCR), and commercial automated assays, the Cobas Amplicor System from Roche Diagnostic Systems (aPCR). Sixty-four (9.7%) specimens were culture-positive for M. tuberculosis. Eleven (1.7%) specimens culture-positive for nontuberculosis mycobacteria were negative by all three PCR assays. The resolved performance of bPCR-ELISA, nPCR, and aPCR was found at sensitivities of 97%, 94%, and 97%, respectively. All three PCR assays exhibited a 100% specificity. In evaluation of bPCR-ELISA, a clear distinction between PCR-positive and PCR-negative specimens when an OD405 value of 0.6 was chosen as cut-off. With serial dilutions of M. tuberculosis H37Rv DNA, the detection limit of bPCR-ELISA was found to be 0.75 cfu per reaction at OD405 value of 0.6. Our developed bPCR-ELISA provides a highly sensitive and low-costing molecular diagnosis suitable for developing countries with high prevalence of tuberculosis. © 2004 Elsevier Inc. All rights reserved.link_to_subscribed_fulltex

Slow-release fluoride devices: a literature review

Although the prevalence of caries has decreased dramatically over the past decades, it has become a polarised disease, with most of subjects presenting low caries levels and few individuals accounting for most of the caries affected surfaces. Thus it become evident for the need of clinical approaches directed at these high-risk patients, in order to overcome problems related to compliance and low attendance at dental care centres. Slow-release fluoride devices were developed based on the inverse relationship existing between intra-oral fluoride levels and dental caries experience. The two main types of slow-release devices - copolymer membrane type and glass bead - are addressed in the present review. A substantial number of studies have demonstrated that these devices are effective in raising intra-oral F concentrations at levels able to reduce enamel solubility, resulting in a caries-protective effect. Studies in animals and humans demonstrated that the use of these devices was able to also protect the occlusal surfaces, not normally protected by conventional fluoride regimens. However, retention rates have been shown to be the main problem related to these devices and still requires further improvements. Although the results of these studies are very promising, further randomised clinical trials are needed in order to validate the use of these devices in clinical practice. The concept of continuously providing low levels of intra-oral fluoride has great potential for caries prevention in high caries-risk groups

(En)visioning place-based adaptation to sea-level rise

Sustainable climate change adaptation requires an understanding of people\u27s place attachments, so that potential impacts and trade-offs are illuminated when making adaptation decisions. Methods are needed that elucidate these important, but often intangible, place attachments at risk. A study was undertaken to explore place attachment, and how these person–place bonds might be impacted by flooding and sea-level rise. It engaged with a small town in coastal Australia that is already highly vulnerable to flooding, and which has been subject to numerous policy directives intended to reduce climate change-induced flood risk. The town therefore acts as an analogue for climate change adaptation in other semi-rural coastal communities. Photo-elicitation was found to be highly effective at elucidating multifarious dimensions of residents\u27 place attachment. The attachments that were likely to be affected by flooding (and adapting to flood risk) were encapsulated in: the personal and communal identities associated with the tourism and fishing industries, the sense of belonging from living and re-living family connections to local places, and the sense of community and enjoyment derived from diverse recreational activities. The photo-elicitation process provided different outcomes to conventional interviews, focus groups and questionnaires. Participants sought to both vision (by elucidating their current experiences) and re-envision (in advocating for different futures) their everyday experiences of adapting to flooding through their photographs and accompanying narratives. A video introduction to this paper is available at: https://vimeo.com/83484905