Although feathers are commonly used to monitor mercury (Hg) in avian populations, their reliability as a sampling matrix has not been thoroughly assessed for many avian species, including most ...songbirds (Order Passeriformes). To better understand relationships between total Hg (THg) concentrations in feathers and other tissues for birds in the thrush and sparrow families, we (1) examined variation in THg concentrations among tissues, including feathers from six different tracts, nails, liver, and muscle; (2) tested relationships between THg concentrations in the various feather tracts and those in internal tissues from the same birds, to assess the predictive power of feather THg, and; (3) compared these relationships to those between THg concentrations in nails and internal tissues, to assess the viability of nails as a non-lethal sampling alternative. THg concentrations in all feather tracts and nails were consistently higher than those in the liver and muscle, and THg was higher in the thrushes than the sparrows. When comparing feather tracts, we observed high variation within some individuals, suggesting that estimates of Hg exposure could vary depending on which feather was sampled. Despite this variation, feather type had little effect on the predictive power of feather THg concentrations, which ranged from extremely weak in the sparrows (0.09 ≤
R
2
≤ 0.16) to moderate (0.29 ≤
R
2
≤ 0.42) in the thrushes. Alternatively, we found that nail samples better predicted internal tissue THg concentrations in both the thrushes (0.44 ≤
R
2
≤ 0.48) and sparrows (0.70 ≤
R
2
≤ 0.78). Nails have been used to monitor Hg in mammals and reptiles, but their reliability as a sampling matrix for monitoring Hg in avian populations has yet to be assessed for most taxa. While nails exhibit stronger relationships to internal tissue THg concentrations, they may not be an effective sampling option for all avian species because the collection of sizable nail samples could harm living birds, particularly small songbirds. However, this method may be reasonable for retrospective museum studies. Overall, our results suggest that, despite their current use in the literature, feathers are not a suitable sampling matrix for Hg monitoring in some songbird species.
Herbicides are commonly deployed as the front-line treatment to control infestations of weeds in native ecosystems and among crop plants in agriculture. However, the prevalence of herbicide ...resistance in many species is a major global challenge. The specificity and effectiveness of herbicides acting on diverse weed species are tightly linked to targeted proteins. The conservation and variance at these sites among different weed species remain largely unexplored. Using novel genome data in a genome-guided approach, 12 common herbicide-target genes and their coded proteins were identified from seven species of Weeds of National Significance in Australia:
Alternanthera philoxeroides
(alligator weed),
Lycium ferocissimum
(African boxthorn),
Senecio madagascariensis
(fireweed),
Lantana camara
(lantana),
Parthenium hysterophorus
(parthenium),
Cryptostegia grandiflora
(rubber vine), and
Eichhornia crassipes
(water hyacinth). Gene and protein sequences targeted by the acetolactate synthase (ALS) inhibitors and glyphosate were recovered. Compared to structurally resolved homologous proteins as reference, high sequence conservation was observed at the herbicide-target sites in the ALS (target for ALS inhibitors), and in 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase (target for glyphosate). Although the sequences are largely conserved in the seven phylogenetically diverse species, mutations observed in the ALS proteins of fireweed and parthenium suggest resistance of these weeds to ALS-inhibiting and other herbicides. These protein sites remain as attractive targets for the development of novel inhibitors and herbicides. This notion is reinforced by the results from the phylogenetic analysis of the 12 proteins, which reveal a largely consistent vertical inheritance in their evolutionary histories. These results demonstrate the utility of high-throughput genome sequencing to rapidly identify and characterize gene targets by computational methods, bypassing the experimental characterization of individual genes. Data generated from this study provide a useful reference for future investigations in herbicide discovery and development.
To describe the incidence, clinical and demographic factors, and treatment patterns associated with discordant elevated alpha-fetoprotein (AFP) findings in patients with pure seminomatous histology.
...We queried the National Cancer Database to identify patients with testicular germ cell tumors (GCT) diagnosed in 2011-2015. Patients were grouped based on histologic diagnosis and pre-operative serum AFP level.
Of 18,616 patients diagnosed with testicular GCT, 53% (N = 9,849) had pure seminomatous histology, of whom 8.3% (N = 821) had an elevated serum AFP pre-operatively. Non-white patients with seminoma were more likely to have a pre-op elevated AFP (OR 1.42; 95% CI: 1.10-1.83); patients treated at higher volume centers were less likely to have a pre-op elevated AFP (0.66, 95% CI: 0.53-0.83). Patients with seminoma with elevated AFP received adjuvant radiation more frequently than those with NSGCT (Stage I: 15% vs 0.2%, P <.01; Stage II: 21.9% vs 0.1%, P <.01) and less frequently underwent retroperitoneal lymph node dissection (RPLND) (Stage 1: 1.9% vs 11.1% P <.01; Stage II: 8.8% vs 17.4%, P <.01).
The detection of elevated serum alpha-fetoprotein (AFP) in patients with pure seminomatous testicular germ cell tumors (GCT) is a discordant finding that implies the presence of occult non-seminomatous GCT (NSGCT) elements. 8% of patients with pure seminomatous GCTs had diagnostically discordant elevated pre-operative AFP levels. Despite recommendations to manage these patients as NSGCT, patients with seminoma and elevated AFP were managed in a fashion comparable to those with seminoma and normal AFP levels.
A critical need exists in low-income and middle-income countries for low-cost, low-tech, yet highly reliable and scalable testing for SARS-CoV-2 virus that is robust against circulating variants.
To ...assess whether a smartphone-based assay is suitable for SARS-CoV-2 and influenza virus testing without requiring specialized equipment, accessory devices, or custom reagents.
This cohort study enrolled 2 subgroups of participants (symptomatic and asymptomatic) at Santa Barbara Cottage Hospital. The symptomatic group consisted of 20 recruited patients who tested positive for SARS-CoV-2 with symptoms; 30 asymptomatic patients were recruited from the same community, through negative admission screening tests for SARS-CoV-2. The smartphone-based real-time loop-mediated isothermal amplification (smaRT-LAMP) was first optimized for analysis of human saliva samples spiked with either SARS-CoV-2 or influenza A or B virus; these results then were compared with those obtained by side-by-side analysis of spiked samples using the Centers for Disease Control and Prevention (CDC) criterion-standard reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) assay. Next, both assays were used to test for SARS-CoV-2 and influenza viruses present in blinded clinical saliva samples obtained from 50 hospitalized patients. Statistical analysis was performed from May to June 2021.
Testing for SARS-CoV-2 and influenza A and B viruses.
SARS-CoV-2 and influenza infection status and quantitative viral load were determined.
Among the 50 eligible participants with no prior SARS-CoV-2 infection included in the study, 29 were men. The mean age was 57 years (range, 21 to 93 years). SmaRT-LAMP exhibited 100% concordance (50 of 50 patient samples) with the CDC criterion-standard diagnostic for SARS-CoV-2 sensitivity (20 of 20 positive and 30 of 30 negative) and for quantitative detection of viral load. This platform also met the CDC criterion standard for detection of clinically similar influenza A and B viruses in spiked saliva samples (n = 20), and in saliva samples from hospitalized patients (50 of 50 negative). The smartphone-based LAMP assay was rapid (25 minutes), sensitive (1000 copies/mL), low-cost (<$7/test), and scalable (96 samples/phone).
In this cohort study of saliva samples from patients, the smartphone-based LAMP assay detected SARS-CoV-2 infection and exhibited concordance with RT-qPCR tests. These findings suggest that this tool could be adapted in response to novel CoV-2 variants and other pathogens with pandemic potential including influenza and may be useful in settings with limited resources.
Partner notification is essential to the comprehensive case management of sexually transmitted infections. Systematic reviews and mathematical modelling can be used to synthesise information about ...the effects of new interventions to enhance the outcomes of partner notification.
To study the effectiveness and cost-effectiveness of traditional and new partner notification technologies for curable sexually transmitted infections (STIs).
Secondary data analysis of clinical audit data; systematic reviews of randomised controlled trials (MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials) published from 1 January 1966 to 31 August 2012 and of studies of health-related quality of life (HRQL) MEDLINE, EMBASE, ISI Web of Knowledge, NHS Economic Evaluation Database (NHS EED), Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment (HTA) published from 1 January 1980 to 31 December 2011; static models of clinical effectiveness and cost-effectiveness; and dynamic modelling studies to improve parameter estimation and examine effectiveness.
General population and genitourinary medicine clinic attenders.
Heterosexual women and men.
Traditional partner notification by patient or provider referral, and new partner notification by expedited partner therapy (EPT) or its UK equivalent, accelerated partner therapy (APT).
Population prevalence; index case reinfection; and partners treated per index case.
Enhanced partner therapy reduced reinfection in index cases with curable STIs more than simple patient referral risk ratio (RR) 0.71; 95% confidence interval (CI) 0.56 to 0.89. There are no randomised trials of APT. The median number of partners treated for chlamydia per index case in UK clinics was 0.60. The number of partners needed to treat to interrupt transmission of chlamydia was lower for casual than for regular partners. In dynamic model simulations, >10% of partners are chlamydia positive with look-back periods of up to 18 months. In the presence of a chlamydia screening programme that reduces population prevalence, treatment of current partners achieves most of the additional reduction in prevalence attributable to partner notification. Dynamic model simulations show that cotesting and treatment for chlamydia and gonorrhoea reduce the prevalence of both STIs. APT has a limited additional effect on prevalence but reduces the rate of index case reinfection. Published quality-adjusted life-year (QALY) weights were of insufficient quality to be used in a cost-effectiveness study of partner notification in this project. Using an intermediate outcome of cost per infection diagnosed, doubling the efficacy of partner notification from 0.4 to 0.8 partners treated per index case was more cost-effective than increasing chlamydia screening coverage.
There is evidence to support the improved clinical effectiveness of EPT in reducing index case reinfection. In a general heterosexual population, partner notification identifies new infected cases but the impact on chlamydia prevalence is limited. Partner notification to notify casual partners might have a greater impact than for regular partners in genitourinary clinic populations. Recommendations for future research are (1) to conduct randomised controlled trials using biological outcomes of the effectiveness of APT and of methods to increase testing for human immunodeficiency virus (HIV) and STIs after APT; (2) collection of HRQL data should be a priority to determine QALYs associated with the sequelae of curable STIs; and (3) standardised parameter sets for curable STIs should be developed for mathematical models of STI transmission that are used for policy-making.
The National Institute for Health Research Health Technology Assessment programme.
Chlamydia trachomatis is the most common bacterial sexually transmitted infection (STI) in many developed countries. The highest prevalence rates are found among young adults who have frequent ...partner change rates. Three published individual-based models have incorporated a detailed description of age-specific sexual behaviour in order to quantify the transmission of C. trachomatis in the population and to assess the impact of screening interventions. Owing to varying assumptions about sexual partnership formation and dissolution and the great uncertainty about critical parameters, such models show conflicting results about the impact of preventive interventions. Here, we perform a detailed evaluation of these models by comparing the partnership formation and dissolution dynamics with data from Natsal 2000, a population-based probability sample survey of sexual attitudes and lifestyles in Britain. The data also allow us to describe the dispersion of C. trachomatis infections as a function of sexual behaviour, using the Gini coefficient. We suggest that the Gini coefficient is a useful measure for calibrating infectious disease models that include risk structure and highlight the need to estimate this measure for other STIs.
Background/aim: The National Chlamydia Screening Programme (NCSP) is being implemented in England. This study aims to estimate the cost effectiveness of (a) the NCSP strategy (annual screening offer ...to men and women aged under 25 years) and (b) alternative screening strategies. Methods: A stochastic, individual based, dynamic sexual network model was combined with a cost effectiveness model to estimate the complications and associated costs of chlamydial infection. The model was constructed and parameterised from the perspective of the National Health Service (NHS) (England), including the direct costs of infection, complications and screening. Unit costs were derived from standard data sources and published studies. The average and incremental cost effectiveness ratio (cost per major outcome averted or quality adjusted life year (QALY) gained) of chlamydia screening strategies targeting women and/or men of different age groups was estimated. Sensitivity analyses were done to explore model uncertainty. Results: All screening strategies modelled are likely to cost the NHS money and improve health. If pelvic inflammatory disease (PID) progression is less than 10% then screening at any level is unlikely to be cost effective. However, if PID progression is 10% or higher the NCSP strategy compared to no screening appears to be cost effective. The incremental cost effectiveness analysis suggests that screening men and women aged under 20 years is the most beneficial strategy that falls below accepted thresholds. There is a high degree of uncertainty in the findings. Conclusions: Offering an annual screening test to men and women aged under 20 years may be the most cost effective strategy (that is, under accepted thresholds) if PID progression is 10% or higher.
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