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To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1532-5415.2008.01949.x Byline: Emily R. Adams ([double dagger]), Vikki G. Nolan (*), Stacy L. Andersen ([dagger]), Thomas T. Perls ([dagger]), Dellara F. Terry ([dagger]) Keywords: centenarian; longevity; morbidity; familial Abstract: OBJECTIVES: To assess the relative incidence of age-related diseases in a group of centenarian offspring who have thus far been considered to be predisposed to 'healthy' aging. DESIGN: Longitudinal study. SETTING: Nationwide sample. PARTICIPANTS: Four hundred forty centenarian offspring and 192 referent cohort subjects who met inclusion criteria of having initial and follow-up health questionnaire data available. Median age of both cohorts was 72 at the initial health questionnaire. MEASUREMENTS: Initial health questionnaires were collected from 1997 to 2006. Follow-up questionnaires were collected from 2004 to 2007. The mean period of follow-up was 3.5[+ or -]1.7 years for the centenarian offspring and 3.9[+ or -]2.2 years for the referent cohort. RESULTS: During the follow-up period, centenarian offspring had a 78% lower risk of myocardial infarction (P CONCLUSION: These findings suggest that centenarian offspring retain some important cardiovascular advantages over time over similarly aged referent cohort subjects. These findings reinforce the notion that there may be physiological reasons that longevity runs in families and that centenarian offspring are more likely to age in better cardiovascular health and with a lower mortality than their peers. Author Affiliation: (From the*)Department of Epidemiology, School of Public Health, Boston University, Boston, Massachusetts ([dagger])New England Centenarian Study, Geriatrics Section, Department of Medicine ([double dagger])School of Medicine, Boston University and Boston Medical Center, Boston, Massachusetts. Article note: Address correspondence to Dellara F. Terry, MD, MPH, Geriatrics Section, Boston Medical Center, 88 East Newton St., Robinson 2, Boston, MA 02118. E-mail: laterry@bu.edu

•Development and evaluation of a novel air-dried HRM assay to detect eight major ESBL and carbapenemase genes.•Sensitivity and specificity of the air-dried HRM assay versus the reference molecular tests was 94.7–98.3% and 98.5–99.2%.•Assay had overall agreement of 91.1% in predicting phenotypic resistance to cefotaxime and meropenem in Enterobacteriaceae.•Cross-platform validation showed almost perfect reproducibility in five different qPCR platforms.•No loss of sensitivity was observed after 8 months of storage at room, refrigerator and oven temperatures.

With the push towards control and elimination of soil-transmitted helminthiasis and schistosomiasis in low- and middle-income countries, there is a need to develop alternative diagnostic assays that complement the current in-country resources, preferably at a lower cost. Here, we describe a novel high-resolution melt (HRM) curve assay with six PCR primer pairs, designed to sub-regions of the nuclear ribosomal locus. Used within a single reaction and dye detection channel, they are able to discriminate Ancylostoma duodenale , Necator americanus , Strongyloides stercoralis , Ascaris lumbricoides , Trichuris trichiuria and Schistosoma spp. by HRM curve analysis. Here we describe the primers and the results of a pilot assessment whereby the HRM assay was tested against a selection of archived fecal samples from Ghanaian children as characterized by Kato–Katz and real-time PCR analysis with species-specific TaqMan hydrolysis probes. The resulting sensitivity and specificity of the HRM was 80 and 98.6% respectively. We judge the assay to be appropriate in modestly equipped and resourced laboratories. This method provides a potentially cheaper alternative to the TaqMan method for laboratories in lower resource settings. However, the assay requires a more extensive assessment as the samples used were not representative of all target organisms. [ABSTRACT FROM AUTHOR]

Countries in the Indian subcontinent have committed to reducing the incidence of kala-azar, a clinical manifestation of visceral leishmaniasis, to below 1 in 10,000 by 2020. We address the role of timing of use and accuracy of diagnostics in kala-azar control and elimination. We use empirical data on health-seeking behaviour and health-system performance from the Indian state of Bihar, Bangladesh and Nepal to parameterize a mathematical model. Diagnosis of cases is key to case management, control and surveillance. Treatment of cases prevents onward transmission, and we show that the differences in time to diagnosis in these three settings explain the observed differences in incidence. Shortening the time from health-care seeking to diagnosis is likely to lead to dramatic reductions in incidence in Bihar, bringing the incidence down to the levels seen in Bangladesh and Nepal. The results emphasize the importance of maintaining population and health-system awareness, particularly as transmission and disease incidence decline. We explore the possibility of diagnosing patients before the onset of clinical kala-azar (before 14 days fever), and show that this could have a marked impact on incidence, even for a moderately sensitive test. However, limited specificity (that results in false positives) is a major barrier to such a strategy. Diagnostic tests of high specificity used at an early stage of active infection, even if sensitivity is only moderate, could have a key role in the control of kala-azar, and prevent its resurgence when paired with the passive health-care system and tests of high sensitivity, such as the test for rK39 antibody response.This article has not been written or reviewed by Nature editors. Nature accepts no responsibility for the accuracy of the information provided.

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ABSTRACTTuberculosis (TB) is a global public health problem, with the highest burden occurring in low-income countries. In these countries, the use of more sensitive diagnostics, such as Xpert MTB/RIF (Xpert), is still limited by costs. A cost-saving strategy to diagnose other diseases is to pool samples from various individuals and test them with single tests. The samples in positive pool samples are then retested individually to identify the patients with the disease. We assessed a pooled testing strategy to optimize the affordability of Xpert for the diagnosis of TB. Adults with presumptive TB attending hospitals or identified by canvassing of households in Abuja, Nigeria, were asked to provide sputum for individual and pooled (4 per pool) testing. The agreement of the results of testing of individual and pooled samples and costs were assessed. A total of 738 individuals submitted samples, with 115 (16%) being Mycobacterium tuberculosispositive. Valid Xpert results for individual and pooled samples were available for 718 specimens. Of these, testing of pooled samples detected 109 (96%) of 114 individual M. tuberculosis-positive samples, with the overall agreement being 99%. Xpert semiquantitative M. tuberculosislevels had a positive correlation with the smear grades, and the individual sample-positive/pooled sample-negative results were likely due to the M. tuberculosisconcentration being below the detection limit. The strategy reduced cartridge costs by 31%. Savings were higher with samples from individuals recruited in the community, where the proportion of positive specimens was low. The results of testing of pooled samples had a high level of agreement with the results of testing of individual samples, and use of the pooled testing strategy reduced costs and has the potential to increase the affordability of Xpert in countries with limited resources.

Variation in clinical accuracy of molecular diagnostic methods for cutaneous leishmaniasis (CL) is commonly observed depending on the sample source, the method of DNA recovery and the molecular test. Few attempts have been made to compare these variables. Two swab and aspirate samples from lesions of patients with suspected CL (n = 105) were evaluated alongside standard diagnosis by microscopic detection of amastigotes or culture of parasites from lesion material. Three DNA extraction methods were compared: Qiagen on swab and aspirate specimens, Isohelix on swabs and Boil/Spin of lesion aspirates. Recovery of Leishmania DNA was evaluated for each sample type by real-time polymerase chain reaction detection of parasitic 18S rDNA, and the diagnostic accuracy of the molecular method determined. Swab sampling combined with Qiagen DNA extraction was the most efficient recovery method for Leishmania DNA, and was the most sensitive (98%; 95% CI: 91–100%) and specific (84%; 95% CI: 64–95%) approach. Aspirated material was less sensitive at 80% (95% CI: 70–88%) and 61% (95% CI: 50–72%) when coupled to Qiagen or Boil-Spin DNA extraction, respectively. Swab sampling of lesions was painless, simple to perform and coupled with standardized DNA extraction enhances the feasibility of molecular diagnosis of CL. [ABSTRACT FROM PUBLISHER]

ABSTRACTCritical to the search for new anti-leishmanial drugs is the availability of high-throughput screening (HTS) methods to test chemical compounds against the relevant stage for pathogenesis, the intracellular amastigotes. Recent progress in automated microscopy and genetic recombination has produced powerful tools for drug discovery. Nevertheless, a simple and efficient test for measuring drug activity against Leishmaniaclinical isolates is lacking. Here we describe a quantitative colorimetric assay in which the activity of a Leishmanianative enzyme is used to assess parasite viability. Enzymatic reduction of disulfide trypanothione, monitored by a microtiter plate reader, was used to quantify the growth of Leishmaniaparasites. An excellent correlation was found between the optical density at 412 nm and the number of parasites inoculated. Pharmacological validation of the assay was performed against the conventional alamarBlue method for promastigotes and standard microscopy for intracellular amastigotes. The activity of a selected-compound panel, including several anti-leishmanial reference drugs, demonstrated high consistency between the newly developed assay and the reference method and corroborated previously published data. Quality assessment with standard measures confirmed the robustness and reproducibility of the assay, which performed in compliance with HTS requirements. This simple and rapid assay provides a reliable, accurate method for screening anti-leishmanial agents, with high throughput. The basic equipment and manipulation required to perform the assay make it easy to implement, simplifying the method for scoring inhibitor assays.