The relationship between eDNA particle concentration and organism abundance in nature is strengthened by allometric scaling.

Organism abundance is a critical parameter in ecology, but its estimation is often challenging. Approaches utilizing eDNA to indirectly estimate abundance have recently generated substantial interest. However, preliminary correlations observed between eDNA concentration and abundance in nature are typically moderate in strength with significant unexplained variation. Here, we apply a novel approach to integrate allometric scaling coefficients into models of eDNA concentration and organism abundance. We hypothesize that eDNA particle production scales nonlinearly with mass, with scaling coefficients < 1. Wild populations often exhibit substantial variation in individual body size distributions; we therefore predict that the distribution of mass across individuals within a population will influence population-level eDNA production rates. To test our hypothesis, we collected standardized body size distribution and mark-recapture abundance data using whole-lake experiments involving nine populations of brook trout. We correlated eDNA concentration with three metrics of abundance: density (individuals/ha), biomass (kg/ha) and allometrically scaled mass (ASM) (∑(individual mass0.73 )/ha). Density and biomass were both significantly positively correlated with eDNA concentration (adj. r2  = 0.59 and 0.63, respectively), but ASM exhibited improved model fit (adj. r2  = 0.78). We also demonstrate how estimates of ASM derived from eDNA samples in "unknown" systems can be converted to biomass or density estimates with additional size-structure data. Future experiments should empirically validate allometric scaling coefficients for eDNA production, particularly where substantial intraspecific size distribution variation exists. Incorporating allometric scaling may improve predictive models to the extent that eDNA concentration may become a reliable indicator of abundance in nature.

Risk-mitigating behaviours in people with inflammatory skin and joint disease during the COVID-19 pandemic differ by treatment type: a cross-sectional patient survey.

BACKGROUND: Registry data suggest that people with immune-mediated inflammatory diseases (IMIDs) receiving targeted systemic therapies have fewer adverse coronavirus disease 2019 (COVID-19) outcomes compared with patients receiving no systemic treatments. OBJECTIVES: We used international patient survey data to explore the hypothesis that greater risk-mitigating behaviour in those receiving targeted therapies may account, at least in part, for this observation. METHODS: Online surveys were completed by individuals with psoriasis (globally) or rheumatic and musculoskeletal diseases (RMDs) (UK only) between 4 May and 7 September 2020. We used multiple logistic regression to assess the association between treatment type and risk-mitigating behaviour, adjusting for clinical and demographic characteristics. We characterized international variation in a mixed-effects model. RESULTS: Of 3720 participants (2869 psoriasis, 851 RMDs) from 74 countries, 2262 (60·8%) reported the most stringent risk-mitigating behaviour (classified here under the umbrella term 'shielding'). A greater proportion of those receiving targeted therapies (biologics and Janus Kinase inhibitors) reported shielding compared with those receiving no systemic therapy [adjusted odds ratio (OR) 1·63, 95% confidence interval (CI) 1·35-1·97]. The association between targeted therapy and shielding was preserved when standard systemic therapy was used as the reference group (OR 1·39, 95% CI 1·23-1·56). Shielding was associated with established risk factors for severe COVID-19 [male sex (OR 1·14, 95% CI 1·05-1·24), obesity (OR 1·37, 95% CI 1·23-1·54), comorbidity burden (OR 1·43, 95% CI 1·15-1·78)], a primary indication of RMDs (OR 1·37, 95% CI 1·27-1·48) and a positive anxiety or depression screen (OR 1·57, 95% CI 1·36-1·80). Modest differences in the proportion shielding were observed across nations. CONCLUSIONS: Greater risk-mitigating behaviour among people with IMIDs receiving targeted therapies may contribute to the reported lower risk of adverse COVID-19 outcomes. The behaviour variation across treatment groups, IMIDs and nations reinforces the need for clear evidence-based patient communication on risk-mitigation strategies and may help inform updated public health guidelines as the pandemic continues.

Small population size and low genomic diversity have no effect on fitness in experimental translocations of a wild fish.

Little empirical work in nature has quantified how wild populations with varying effective population sizes and genetic diversity perform when exposed to a gradient of ecologically important environmental conditions. To achieve this, juvenile brook trout from 12 isolated populations or closed metapopulations that differ substantially in population size and genetic diversity were transplanted to previously fishless ponds spanning a wide gradient of ecologically important variables. We evaluated the effect of genome-wide variation, effective population size (Ne), pond habitat, and initial body size on two fitness correlates (survival and growth). Genetic variables had no effect on either fitness correlate, which was determined primarily by habitat (pond temperature, depth, and pH) and initial body size. These results suggest that some vertebrate populations with low genomic diversity, low Ne, and long-term isolation can represent important sources of variation and are capable of maintaining fitness in, and ultimately persisting and adapting to, changing environments. Our results also reinforce the paramount importance of improving available habitat and slowing habitat degradation for species conservation.

EULAR/ERA-EDTA recommendations for the management of ANCA-associated vasculitis.

In this article, the 2009 European League Against Rheumatism (EULAR) recommendations for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) have been updated. The 2009 recommendations were on the management of primary small and medium vessel vasculitis. The 2015 update has been developed by an international task force representing EULAR, the European Renal Association and the European Vasculitis Society (EUVAS). The recommendations are based upon evidence from systematic literature reviews, as well as expert opinion where appropriate. The evidence presented was discussed and summarised by the experts in the course of a consensus-finding and voting process. Levels of evidence and grades of recommendations were derived and levels of agreement (strengths of recommendations) determined. In addition to the voting by the task force members, the relevance of the recommendations was assessed by an online voting survey among members of EUVAS. Fifteen recommendations were developed, covering general aspects, such as attaining remission and the need for shared decision making between clinicians and patients. More specific items relate to starting immunosuppressive therapy in combination with glucocorticoids to induce remission, followed by a period of remission maintenance; for remission induction in life-threatening or organ-threatening AAV, cyclophosphamide and rituximab are considered to have similar efficacy; plasma exchange which is recommended, where licensed, in the setting of rapidly progressive renal failure or severe diffuse pulmonary haemorrhage. These recommendations are intended for use by healthcare professionals, doctors in specialist training, medical students, pharmaceutical industries and drug regulatory organisations.

Modification of the National Inpatient Medication Chart improves venous thromboembolism prophylaxis rates in high-risk medical patients.

BACKGROUND: Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality in Australia. While there is well-established evidence for the use of VTE prophylaxis in hospital inpatients, adherence to such guidelines is poor. AIM: The aim of the present study is to assess the impact of education and system change on improving rates of VTE prophylaxis in hospital inpatients. METHODS: We performed four consecutive audits of inpatient medical records of a regional hospital service over 2 years. The audits aimed to test the impact of serial interventions at increasing the appropriate use of VTE prophylaxis (based on risk assessment). The interventions were (i) staff education and (ii) a process change that mandated a prophylaxis decision by modifying the National Inpatient Medication Chart with 'VTE avoidance' preprinted in the first medication box. RESULTS: Our results from the baseline study showed that of the 236 medical inpatients reviewed, 80% were at high risk of VTE. Of this high-risk cohort, 34.9% (confidence interval (CI) 28-42%) had appropriate prophylaxis decisions. Post the education intervention, 43.2% (CI 37-49%) of the high-risk cohort received appropriate VTE prophylaxis, an improvement of 8.3% (CI -1% to 18%) from baseline. With the subsequent introduction of a process change, 82.1% (CI 66-92%) of the high-risk cohort received appropriate prophylaxis, an improvement of 47.2% and 38.8% (CI 24-54%) when compared with baseline and education respectively. Retention rates at 11 months postsystem change were 73% (CI 55-86%). CONCLUSIONS: This study therefore concluded that while education has an impact on rates of appropriate VTE prophylaxis, it is system change that has the most marked and sustained effect.

Naringenin degradation by the endophytic diazotroph Herbaspirillum seropedicae SmR1.

Several bacteria are able to degrade flavonoids either to use them as carbon sources or as a detoxification mechanism. Degradation pathways have been proposed for several bacteria, but the genes responsible are not known. We identified in the genome of the endophyte Herbaspirillum seropedicae SmR1 an operon potentially associated with the degradation of aromatic compounds. We show that this operon is involved in naringenin degradation and that its expression is induced by naringenin and chrysin, two closely related flavonoids. Mutation of fdeA, the first gene of the operon, and fdeR, its transcriptional activator, abolished the ability of H. seropedicae to degrade naringenin.

Culture-independent analysis of endophytic bacterial communities associated with Brazilian sugarcane.

Sugarcane is an economically important culture in Brazil. Endophytic bacteria live inside plants, and can provide many benefits to the plant host. We analyzed the bacterial diversity of sugarcane cultivar RB-72454 by cultivation-independent techniques. Total DNA from sugarcane stems from a commercial plantation located in Paraná State was extracted. Partial 16S rRNA genes were amplified and sequenced for library construction. Of 152 sequences obtained, 52% were similar to 16S rRNA from Pseudomonas sp, and 35.5% to Enterobacter sp. The genera Pantoea, Serratia, Citrobacter, and Klebsiella were also represented. The endophytic communities in these sugarcane samples were dominated by the families Enterobacteriaceae and Pseudomonadaceae (class Gammaproteobacteria).

Naringenin regulates expression of genes involved in cell wall synthesis in Herbaspirillum seropedicae.

Five thousand mutants of Herbaspirillum seropedicae SmR1 carrying random insertions of transposon pTnMod-OGmKmlacZ were screened for differential expression of LacZ in the presence of naringenin. Among the 16 mutants whose expression was regulated by naringenin were genes predicted to be involved in the synthesis of exopolysaccharides, lipopolysaccharides, and auxin. These loci are probably involved in establishing interactions with host plants.

Survival of adenovirus types 2 and 41 in surface and ground waters measured by a plaque assay.

To manage artificial recharge systems, it is necessary to understand the inactivation process of microorganisms within aquifers so that requirements regarding storage times and treatment strategies for ground and surface waters can be developed and modeled to improve water management practices. This study was designed to investigate the survival of representative adenoviruses in surface- and groundwaters using a cell culture plaque assay with human lung carcinoma cells (A549) to enumerate surviving viruses. Adenovirus types 2 (Ad2) and 41 (Ad41) were seeded into 50 mL of three sterilized surface waters and groundwaters, and incubated at 10 and 19 °C for up to 301 days. Concentrations of Ad2 and Ad41 were relatively stable in all waters at 10 °C for at least 160 days and in some instances up to 301 days. At 19 °C, virus concentrations were reduced by 99.99% (4 log) after 301 days in surface water. There was approximately 90% (1 log) reduction of both viruses at 19 °C after 160 days of incubation in groundwater samples. There was no overall difference in survival kinetics in surface waters compared to groundwaters. The relatively high stability and long-term survival of adenoviruses in environmental waters at elevated temperatures should be considered in risk assessment models and drinking water management strategies.

Large outbreak of isoniazid-monoresistant tuberculosis in London, 1995 to 2006: case-control study and recommendations.

We conducted a case­control study to examine risk factors for isoniazid-monoresistant Mycobacterium tuberculosis in an ongoing outbreak in London. Cases were defined as individuals with an isoniazid-monoresistant strain diagnosed from 1995 to the third quarter of 2006 with an indistinguishable restriction fragment length polymorphism (RFLP) or mycobacterial interspersed repetitive unit (MIRU)-variable number tandem repeats (VNTR) pattern who were resident in or had epidemiological links with London. Controls were all other individuals reported with tuberculosis to the Health Protection Agency London regional epidemiology unit or the HPA London TB Register during 2000 to 2005. Of 293 cases, 153 (52%) were sputum smear-positive compared with 3,266 (18%) of controls. Cases were more likely to be young adults (aged between 15 and 34 years), born in the United Kingdom (OR: 2.4; 95% CI: 1.7­3.4) and of white (OR: 2.9; 95% CI: 1.8­4.8) or black Caribbean (OR: 12.5; 95% CI: 7.7­20.4) ethnicity, a prisoner at the time of diagnosis (OR: 20.2; 95% CI: 6.7­60.6), unemployed (OR: 4.1; 95% CI: 3.0­5.6), or a drug dealer or sex worker (OR: 187.1; 95% CI: 28.4­1,232.3). A total of 113 (39%) of cases used drugs and 54 (18%) were homeless. Completion of treatment gradually improved in cases from 55% among those diagnosed up to the end of 2002 compared with 65% by the end of 2006. Treatment completion increased from 79% to 83% in controls from 2000 to 2005. There are complex social challenges facing many cases in this outbreak that need to be addressed if medical interventions are to be successful.

MYSTAT: A compact potentiostat/galvanostat for general electrochemistry measurements.

An open-source potentiostat/galvanostat instrument design is introduced that provides the ability to take accurate measurements over a current range of ±200 mA and a potential range of ±12 V. The improved capability of the instrument compared to the previously published design upon which it is based makes it suitable for performing a wider range of electrochemical measurements including the ability to use larger working electrodes, study of high current density processes, study of electrochemistry in nonaqueous solutions and use in high voltage processes such as electrophoretic deposition. The instrument can be controlled from any computer capable of running the Python programming language, including a low-cost Raspberry Pi. Unlike many commercial potentiostat designs, the instrument is completely open-source, giving researchers the ability to modify the hardware and software as needed for custom measurement techniques. The low cost makes the instrument attractive for research and teaching laboratories in which multiple electrochemical measurements need to be carried out in parallel.

Steric stabilization of thermally responsive N-isopropylacrylamide particles by poly(vinyl alcohol).

Poly(vinyl alcohol) (PVA) was used as a steric stabilizer for the dispersion polymerization of cross-linked poly(N-isopropylacrylamide) (PNIPAM) in water. A series of reactions were carried out using PVA of varying molecular weight and degree of hydrolysis. Under appropriate conditions, PNIPAM particles of uniform and controllable size were produced using PVA as the stabilizer. The colloidal stability was investigated by measuring changes in particle size with temperature in aqueous suspensions of varying ionic strength. For comparison, parallel colloidal stability measurements were conducted on PNIPAM particles synthesized with low-molecular-weight ionic surfactants. PVA provides colloidal stability over a wide range of temperature and ionic strength, whereas particles produced with ionic surfactants flocculate in moderate ionic strength solutions upon collapse of the hydrogel as the temperature is increased. Experimental results and theoretical consideration indicate that sterically stabilized PNIPAM particles resulted from the grafting of PVA to the PNIPAM particle surface. The enhanced colloidal stability afforded by PVA allows the temperature-responsive PNIPAM particles to be used under physiological conditions where electrostatic stability is ineffective.

The utility of transoesophageal echocardiography to determine management in suspected embolic stroke.

BACKGROUND: Assessment for source of stroke is a common indication for transoesophageal echocardiography (TOE). Although an abnormality is frequently found, it remains uncertain how frequently the findings alter patient management. Also, the role of transthoracic echocardiography (TTE) prior to or instead of TOE is not well defined. We sought to determine the use of TTE prior to TOE, the outcome of the TOE and its impact on management. METHODS: We retrospectively reviewed the records and echocardiography results of 100 consecutive patients who underwent TOE for any reason at a tertiary hospital. In 35 subjects (35%), the indication was evaluation for source of stroke. Among these, we determined clinical risk factors for stroke, if a TTE was performed prior to their TOE, the results of the TOE and its effect on management. RESULTS: The mean age of the stroke patients was 64.6 years (17-90) and 49% were women. Eighty per cent had at least one risk factor for stroke and 17% had atrial fibrillation. A TTE, performed in 40% prior to the TOE, found an abnormality in 14% (2/14). The TOE showed an abnormality in 71% of patients; 54% had aortic atheroma; 17% PFO; 14% spontaneous echo contrast; 6% left atrial appendage thrombus, 3% left ventricular thrombus and 3% vegetation. In only one patient (3%) the management was altered based on the abnormal TOE findings. CONCLUSION: An abnormality on TOE, although common (71%) and more sensitive than TTE, altered management in only 3% of subjects referred for stroke assessment. Its role requires further consideration.

Extensively drug-resistant tuberculosis in the UK: 1995 to 2007.

BACKGROUND: The emergence of multidrug-resistant tuberculosis (MDRTB) and extensively drug-resistant tuberculosis (XDRTB) is a threat to global tuberculosis control. Limited information is, however, available on the outcome of XDRTB cases. This study describes the susceptibility to second- and third-line antituberculosis drugs among MDRTB cases and treatment outcome of identified XDRTB cases. METHOD: The results of second-line antituberculosis drug susceptibility tests in the UK between January 1995 and December 2007 were retrospectively reviewed and clinicians contacted for treatment outcome of XDRTB cases. Participants included all 678 patients with culture-confirmed MDRTB in the UK. The main outcome measures were the proportion of isolates resistant to second-line antituberculosis drugs and treatment outcome for XDRTB cases. RESULTS: Among MDRTB isolates, levels of resistance to amikacin, capreomycin, ciprofloxacin, cycloserine, ethionamide and p-aminosalicylic acid (PAS) were 5.5, 3.4, 5.6, 5.1, 14.0 and 16.7%, respectively. Six XDRTB cases (0.9% of MDR cases) were identified during this period. Two further cases of XDRTB were reported in 2008. Five individuals with XDRTB died of tuberculosis within 3 years of diagnosis and three are still on treatment. CONCLUSION: Levels of MDRTB remain low, and those of XDRTB very low, in this high income country. The case fatality ratio among XDRTB cases was high despite low levels of HIV co-infection.

Complement 1s is the serine protease that cleaves IGFBP-5 in human osteoarthritic joint fluid.

UNLABELLED: Insulin-like growth factor-I (IGF-I) and IGF binding proteins (IGFBPs) are trophic factors for cartilage and have been shown to be chondroprotective in animal models of osteoarthritis (OA). IGFBP-5 is degraded in joint fluid and inhibition of IGFBP-5 degradation has been shown to enhance the trophic effects of IGF-I. OBJECTIVE: To determine the identity of IGFBP-5 protease activity in human OA joint fluid. METHOD: OA joint fluid was purified and the purified material was analyzed by IGFBP-5 zymography. RESULTS: Both crude joint fluid and purified material contained a single band of proteolytic activity that cleaved IGFBP-5. Immunoblotting of joint fluid for complement 1s (C1s) showed a band that had the same Mr estimate, e.g., 88 kDa. In gel tryptic digestion and subsequent peptide analysis by LC-MS/MS showed that the band contained human C1s. A panel of protease inhibitors was tested for their ability to inhibit IGFBP-5 cleavage by the purified protease. Three serine protease inhibitors, FUT175 and CP-143217 and CB-349547 had IC50's between 1 and 6 microM. Two other serine protease inhibitors had intermediate activity (e.g., IC50's 20-40 microM) and MMP inhibitors had no detectible activity at concentrations up to 300 microM. CONCLUSION: Human OA fluid contains a serine protease that cleaves IGFBP-5. Zymography, immunoblotting and LC-MS/MS analysis indicate that C1s is the protease that accounts for this activity.

Seismic data from man-made impacts on the moon.

Unusually long reverberations were recorded from two lunar impacts by a seismic station installed on the lunar surface by the Apollo 12 astronauts. Seismic data from these impacts suggest that the lunar mare in the region of the Apollo 12 landing site consists of material with very low seismic velocities near the surface, with velocity increasing with depth to 5 to 6 kilometers per second (for compressional waves) at a depth of 20 kilometers. Absorption of seismic waves in this structure is extremely low relative to typical continental crustal materials on earth. It is unlikely that a major boundary similar to the crustmantle interface on earth exists in the outer 20 kilometers of the moon. A combination of dispersion and scattering of surface waves probably explains the lunar seismic reverberation. Scattering of these waves implies the presence of heterogeneity within the outer zone of the mare on a scale of from several hundred meters (or less) to several kilometers. Seismic signals from 160 events of natural origin have been recorded during the first 7 months of operation of the Apollo 12 seismic station. At least 26 of the natural events are small moonquakes. Many of the natural events are thought to be meteoroid impacts.