Reorientational Dynamics in Y(BH4)3·xNH3 (x = 0, 3, and 7): The Impact of NH3 on BH4- Dynamics.

The reorientational dynamics of Y(BH4)3·xNH3 (x = 0, 3, and 7) was studied using quasielastic neutron scattering (QENS) and neutron spin echo (NSE). The results showed that changing the number of NH3 ligands drastically alters the reorientational mobility of the BH4- anion. From the QENS experiments, it was determined that the BH4- anion performs 2-fold reorientations around the C2 axis in Y(BH4)3, 3-fold reorientations around the C3 axis in Y(BH4)3·3NH3, and either 2-fold reorientations around the C2 axis or 3-fold reorientations around the C3 axis in Y(BH4)3·7NH3. The relaxation time of the BH4- anion at 300 K decreases from 2 × 10-7 s for x = 0 to 1 × 10-12 s for x = 3 and to 7 × 10-13 s for x = 7. In addition to the reorientational dynamics of the BH4- anion, it was shown that the NH3 ligands exhibit 3-fold reorientations around the C3 axis in Y(BH4)3·3NH3 and Y(BH4)3·7NH3 as well as 3-fold quantum mechanical rotational tunneling around the same axis at 5 K. The new insights constitute a significant step toward understanding the relationship between the addition of ligands and the enhanced ionic conductivity observed in systems such as LiBH4·xNH3 and Mg(BH4)2·xCH3NH2.

Climate footprint assessment of plastic waste pyrolysis and impacts on the Danish waste management system.

Increased plastic recycling is necessary to reduce environmental impacts related to manufacturing and end-of-life of plastic products, however, mechanical recycling (MR) - currently the most widespread recycling option for plastic waste - is limited by quality requirements for inputs and reduced quality of outputs. In this study, pyrolysis of plastic waste is assessed against MR, municipal solid waste incineration (MSWI) and fuel substitution through climate footprint assessment (CFA) based on primary data from pyrolysis of plastic waste sourced from Danish waste producers. Results of the CFA are scaled to the Danish plastic waste resource in an impact assessment of current Danish plastic waste management, and scenarios are constructed to assess reductions through utilization of pyrolysis. Results of the CFA show highest benefits utilizing pyrolysis for monomer recovery (-1400 and -4800 kg CO2e per ton polystyrene (PS) and polymethyl methacrylate (PMMA), respectively) and MR for single polymer polyolefins (-1000 kg CO2e per ton PE). The two management options perform similarly with mixed plastic waste (200 kg CO2e per ton plastic waste). MSWI has the highest impact (1600-2200 kg CO2e per ton plastic waste) and should be avoided when alternatives are available. Scaling the results of the CFA to the full Danish plastic waste resource reveals an impact of 0.79 Mt CO2e in year 2020 of current plastic waste management. Utilizing pyrolysis to manage MR residues reduces the system impact by 15%. Greater reductions are possible through increased separation of plastic from residual waste. The best performance is achieved through a combination of MR and pyrolysis.

Previous fracture and subsequent fracture risk: a meta-analysis to update FRAX.

A large international meta-analysis using primary data from 64 cohorts has quantified the increased risk of fracture associated with a previous history of fracture for future use in FRAX. INTRODUCTION: The aim of this study was to quantify the fracture risk associated with a prior fracture on an international basis and to explore the relationship of this risk with age, sex, time since baseline and bone mineral density (BMD). METHODS: We studied 665,971 men and 1,438,535 women from 64 cohorts in 32 countries followed for a total of 19.5 million person-years. The effect of a prior history of fracture on the risk of any clinical fracture, any osteoporotic fracture, major osteoporotic fracture, and hip fracture alone was examined using an extended Poisson model in each cohort. Covariates examined were age, sex, BMD, and duration of follow-up. The results of the different studies were merged by using the weighted ß-coefficients. RESULTS: A previous fracture history, compared with individuals without a prior fracture, was associated with a significantly increased risk of any clinical fracture (hazard ratio, HR = 1.88; 95% CI = 1.72-2.07). The risk ratio was similar for the outcome of osteoporotic fracture (HR = 1.87; 95% CI = 1.69-2.07), major osteoporotic fracture (HR = 1.83; 95% CI = 1.63-2.06), or for hip fracture (HR = 1.82; 95% CI = 1.62-2.06). There was no significant difference in risk ratio between men and women. Subsequent fracture risk was marginally downward adjusted when account was taken of BMD. Low BMD explained a minority of the risk for any clinical fracture (14%), osteoporotic fracture (17%), and for hip fracture (33%). The risk ratio for all fracture outcomes related to prior fracture decreased significantly with adjustment for age and time since baseline examination. CONCLUSION: A previous history of fracture confers an increased risk of fracture of substantial importance beyond that explained by BMD. The effect is similar in men and women. Its quantitation on an international basis permits the more accurate use of this risk factor in case finding strategies.

Evaluation of an individually tailored smoking-cessation intervention for patients with rheumatoid arthritis in an outpatient clinic.

OBJECTIVE: The aim of this study was to evaluate an individually tailored smoking-cessation intervention delivered in rheumatology care and compare the characteristics of patients who quit smoking with those who did not. METHOD: This was an open single-group prospective intervention study over 24 months, with assessments at baseline and at 6, 12, 18, and 24 months. Current smokers with rheumatoid arthritis (RA) were invited to a smoking-cessation programme including behavioural change support, with or without pharmacotherapy. Data on disease activity, medical treatment, and patient-reported outcomes were retrieved from the Swedish Rheumatology Quality Register. The primary outcome was the proportion of patients at month 24 who reported having quit smoking with self-reported 7 day smoking abstinence. RESULTS: In total, 99 patients participated in the study. Median age was 58 years (interquartile range 50-64); 69% were female and 88% rheumatoid factor and/or anti-cyclic citrullinated peptide positive. At 24 months, 21% of the patients had quit smoking. At 6, 12, and 18 months, 12%, 12%, and 14% of patients, respectively, had quit smoking. For patients still smoking at 24 months, the median number of cigarettes per day was significantly reduced from 12 to 6 (p ≤ 0.001). Among patients who had quit smoking at 24 months, a smaller proportion reported anxiety at baseline compared to those still smoking (28% vs 58%, p = 0.02). CONCLUSION: A smoking-cessation intervention including behavioural change support with or without pharmacotherapy can be helpful for a substantial number of RA patients. Anxiety is associated with lower smoking-cessation success rates.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan.

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. INTRODUCTION: The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors. METHODS: A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible. RESULTS: Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed. CONCLUSIONS: These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

Subclinical hyperthyroidism is associated with increased risk of vertebral fractures in older men.

In elderly men included in MrOS-Sweden, subclinical hyperthyroidism (SHyper) was markedly associated with increased risk of vertebral fractures. INTRODUCTION: Overt hyperthyroidism is associated with increased risk of fractures. However, only a few studies have investigated whether SHyper is associated with fracture risk in elderly men. We therefore investigated if SHyper was a risk factor for fractures in Swedish men. METHODS: We followed (median 9.8 years) elderly men (n = 1856; mean age 75, range 69-81 years) participating in the Gothenburg and Malmö subcohorts of the prospective, population-based MrOS-Sweden study. The statistical analyses included Cox proportional hazards regression. SHyper was defined as serum thyroid-stimulating hormone (TSH) < 0.45 mIU/L (n = 38). RESULTS: SHyper was associated with increased risk of all fractures [n = 456; hazard ratio (HR) adjusted for age, study center, and levothyroxine treatment = 1.99, 95% confidence interval (CI): 1.20-3.32], major osteoporotic fractures (MOF, n = 338; HR 2.44, 95% CI: 1.42-4.21), and vertebral fractures (n = 176; HR 3.79, 95% CI: 2.02-7.11). These associations remained after full adjustment for covariates including total hip bone mineral density and in subanalyses including only men with serum free thyroxine ≤ the upper normal limit. However, after exclusion of men receiving levothyroxine treatment, the associations with all fractures and MOF lost significance. CONCLUSIONS: In elderly Swedish men, there was a strong association between SHyper and increased risk of vertebral fractures, whereas the associations with all incident fractures and MOF need to be confirmed in further studies.

Radiology departmental policy compliance with Swedish guidelines regarding post-contrast acute kidney injury for examinations with iodinated contrast media.

INTRODUCTION: Guidelines concerning intravenous iodinated contrast media (CM) during computed tomography (CT) examinations are important to follow to minimize the risk for post-contrast acute kidney injury (PC-AKI). The purpose of this study was to investigate the radiology departmental policy compliance with Swedish guidelines concerning PC-AKI. METHODS: In February 2020, an electronic survey was distributed to the responsible radiographer at 41 radiology departments in all university hospitals and medium-sized hospitals in Sweden. The questions focused on routines around renal functional tests, individualized contrast administration and handling of patients with diabetes mellitus taking metformin. RESULTS: The response rate was 83%. Seventy-six percent (n = 26) of radiology departments calculated estimated glomerular filtration rate (eGFR) from serum creatinine prior to CM administration, but only 24% (n = 8) followed the recommendation to calculate eGFR from both serum creatinine and cystatin C. For acute/inpatients, 55% (n = 18) followed the recommendation that renal functional tests should be performed within 12 h before CM administration. For elective patients, 97% (n = 33) followed the recommendation to have eGFR newer than three months which is acceptable for patients with no history of disease that may have affected renal function. Approximately 80% of the radiology departments followed the recommendation that CM dose always should be individually adjusted to patient eGFR. Seventy-six percent (n = 26) followed the recommendation to continue with metformin at eGFR ≥ 45 ml/min. CONCLUSION: Compliance with the national guidelines was high regarding routines around renal functional tests, dose adjustment of CM and metformin discontinuation. Improvements can be made in using both cystatin C and serum creatinine for eGFR calculations as well as ensuring renal function tests within 12 h for acute/inpatients with acute disease that may affect renal function. IMPLICATIONS FOR PRACTICE: This study raises awareness of the importance of adhering to guidelines in healthcare. To have knowledge about the current level of compliance regarding PCI-AKI is important to maintain and develop effective clinical implementation of guidelines. The variation in practice seen in this study emphasizes the need of more effective implementation strategies to ensure adherence with best practice.

Interplay between the Reorientational Dynamics of the B3H8 - Anion and the Structure in KB3H8.

The structure and reorientational dynamics of KB3H8 were studied by using quasielastic and inelastic neutron scattering, Raman spectroscopy, first-principles calculations, differential scanning calorimetry, and in situ synchrotron radiation powder X-ray diffraction. The results reveal the existence of a previously unknown polymorph in between the α'- and ß-polymorphs. Furthermore, it was found that the [B3H8]- anion undergoes different reorientational motions in the three polymorphs α, α', and ß. In α-KB3H8, the [B3H8]- anion performs 3-fold rotations in the plane created by the three boron atoms, which changes to a 2-fold rotation around the C 2 symmetry axis of the [B3H8]- anion upon transitioning to α'-KB3H8. After transitioning to ß-KB3H8, the [B3H8]- anion performs 4-fold rotations in the plane created by the three boron atoms, which indicates that the local structure of ß-KB3H8 deviates from the global cubic NaCl-type structure. The results also indicate that the high reorientational mobility of the [B3H8]- anion facilitates the K+ cation conductivity, since the 2-orders-of-magnitude increase in the anion reorientational mobility observed between 297 and 311 K coincides with a large increase in K+ conductivity.

Imaging low-mass planets within the habitable zone of α Centauri.

Giant exoplanets on wide orbits have been directly imaged around young stars. If the thermal background in the mid-infrared can be mitigated, then exoplanets with lower masses can also be imaged. Here we present a ground-based mid-infrared observing approach that enables imaging low-mass temperate exoplanets around nearby stars, and in particular within the closest stellar system, α Centauri. Based on 75-80% of the best quality images from 100 h of cumulative observations, we demonstrate sensitivity to warm sub-Neptune-sized planets throughout much of the habitable zone of α Centauri A. This is an order of magnitude more sensitive than state-of-the-art exoplanet imaging mass detection limits. We also discuss a possible exoplanet or exozodiacal disk detection around α Centauri A. However, an instrumental artifact of unknown origin cannot be ruled out. These results demonstrate the feasibility of imaging rocky habitable-zone exoplanets with current and upcoming telescopes.

High platelet count is associated with low bone mineral density: The MrOS Sweden cohort.

In elderly ambulatory men, high platelet and high neutrophil counts are related to low bone mineral density (BMD), after adjustment for relevant covariates. Low hemoglobin (hgb) is even associated with low BMD, but this relationship seems to be dependent on estradiol and osteocalcin. PURPOSE: Blood and bone cells exist in close proximity to each other in the bone marrow. Accumulating evidence, from both preclinical and clinical studies, indicates that these cell types are interconnected. Our hypothesis was that BMD measurements are associated with blood count variables and bone remodeling markers. METHODS: We analyzed blood count variables, bone remodeling markers, and BMD, in subjects from the MrOS cohort from Gothenburg, Sweden. Men with at least one blood count variable (hgb, white blood cell count, or platelet count) analyzed were included in the current analysis (n = 1005), median age 75.3 years (range 69-81 years). RESULTS: Our results show that high platelet counts were related to low BMD at all sites (total hip BMD; r = - 0.11, P = 0.003). No statistically significant association was seen between platelet counts and bone remodeling markers. Neutrophil counts were negatively associated with total body BMD (r = - 0.09, P = 0.006) and total hip BMD (r = - 0.08, P = 0.010), and positively related to serum ALP (r = 0.15, P < 0.001). Hgb was positively related to total hip BMD (r = 0.16, P < 0.001), and negatively to serum osteocalcin (r = - 0.13, P < 0.001). The association between platelet and neutrophil counts and total hip BMD was statistically significant after adjustments for other covariates, but the association between hgb and total hip BMD was dependent on estradiol and osteocalcin. CONCLUSIONS: Our observations support the hypothesis of an interplay between blood and bone components.

Sprayed cultured autologous keratinocytes in the treatment of severe burns: a retrospective matched cohort study.

The standard treatment of burns is early excision followed by autologous skin grafting. The closure of extensive deep burns poses a considerable challenge. Cultured autologous keratinocytes have been used since 1981 in an effort to improve healing. However, the time required to culture the cells and the lack of a dermal component limit the expectations of outcome. Our aim was to compare the duration of hospital stay between patients who were treated with autologous skin grafts and cultured autologous keratinocytes and those who were treated with autologous skin grafting without cultured autologous keratinocytes. In this retrospective study all patients treated with cultured autologous keratinocytes between 2012 and 2015 were matched by size and depth of burn with patients not treated with cultured autologous keratinocytes. Multivariable regression was used to analyse associations between duration of hospital stay and treatment adjusted for age, mortality, size and depth of the burn. Then, we investigated the possibility of differentiation of human bone marrow stem cell line to keratinocyte- like cells as a future direction. The regression analysis showed a coefficient of 17.36 (95% CI -17.69 to 52.40), p= 0.32, for hospital stay in the treatment group, compared with the matched group. Our results showed no difference in the duration of hospital stay between the two treatments. Autologous stem cells should be considered as a future modality of burn management, although further studies are needed.

Le traitement de référence des brûlures est l'excision- greffe précoce, qui est problématique en cas d'atteinte étendue. La culture de kératinocytes autologues est utilisée depuis 1981 dans le but de répondre à cette problématique mais se heure au temps nécessaire à sa mise en oeuvre, ainsi qu'à l'absence de feuillet dermique, génératrice de séquelles. Cette étude a comparé la durée de séjour des patients traité par excision- greffe et culture de kératinocytes à celle des patients traités de manière conventionnelle. Les patients hospitalisés entre 2012 et 2015 ont été comparés à des patients de même surface et profondeur traités conventionnellement, en utilisant une analyse multivariée ajustée sur l'âge, la mortalité, la surface et la profondeur de la brûlure. L'analyse n'est pas significative (coefficient 17,36 ; IC95 -17,69 à 52,4 ; p= 0,32). Il serait utile d'étudier l'utilisation des cellules souches médullaires, différentiées en kératinocytes, dans un protocole de culture.

Population pharmacokinetics of colistin and the relation to survival in critically ill patients infected with colistin susceptible and carbapenem-resistant bacteria.

OBJECTIVES: The aim was to analyse the population pharmacokinetics of colistin and to explore the relationship between colistin exposure and time to death. METHODS: Patients included in the AIDA randomized controlled trial were treated with colistin for severe infections caused by carbapenem-resistant Gram-negative bacteria. All subjects received a 9 million units (MU) loading dose, followed by a 4.5 MU twice daily maintenance dose, with dose reduction if creatinine clearance (CrCL) < 50 mL/min. Individual colistin exposures were estimated from the developed population pharmacokinetic model and an optimized two-sample per patient sampling design. Time to death was evaluated in a parametric survival analysis. RESULTS: Out of 406 randomized patients, 349 contributed pharmacokinetic data. The median (90% range) colistin plasma concentration was 0.44 (0.14-1.59) mg/L at 15 minutes after the end of first infusion. In samples drawn 10 hr after a maintenance dose, concentrations were >2 mg/L in 94% (195/208) and 44% (38/87) of patients with CrCL ≤120 mL/min, and >120 mL/min, respectively. Colistin methanesulfonate sodium (CMS) and colistin clearances were strongly dependent on CrCL. High colistin exposure to MIC ratio was associated with increased hazard of death in the multivariate analysis (adjusted hazard ratio (95% CI): 1.07 (1.03-1.12)). Other significant predictors included SOFA score at baseline (HR 1.24 (1.19-1.30) per score increase), age and Acinetobacter or Pseudomonas as index pathogen. DISCUSSION: The population pharmacokinetic model predicted that >90% of the patients had colistin concentrations >2 mg/L at steady state, but only 66% at 4 hr after start of treatment. High colistin exposure was associated with poor kidney function, and was not related to a prolonged survival.

Risk for hip fracture before and after total knee replacement in Sweden.

We studied the risk for hip fracture before and after total knee replacement (TKR) in the entire population in Sweden. Women and men had a low risk for hip fracture before TKR but an increased risk the first year after TKR. PURPOSE: It is known that osteoarthritis is associated with high bone mass. We therefore studied the risk of hip fracture before and after total knee replacement (TKR), risk of different hip fracture types, and risk subdivided in genders and age groups. METHODS: We followed the total Swedish population born between 1902 and 1952 (n = 4,258,934) during the period 1987-2002 and identified all patients with TKR due to primary OA (n = 39,291), and all patients with hip fracture (n = 195,860) in the Swedish National Inpatient Register. The risk time analyses were based on Poisson regression models. RESULTS: The hazard ratio (HR) for hip fracture the last year before TKR was 0.86 (95% CI 0.74 to 1.00) and the first year after 1.26 (95% CI 1.11 to 1.42) compared to individuals without TKR. The HR for femoral neck fracture 0-10 years after TKR was 0.95 (95% CI 0.89 to 1.01) and for trochanteric fracture was 1.13 (95% CI 1.06 to 1.21). The HR for hip fracture in the age group 50-74 was 1.28 (95% CI 1.14 to 1.43) and in the age group 75-90 years was 0.99 (95% CI 0.94 to 1.04) 0-10 years after TKR, compared to individuals without TKR. CONCLUSION: Individuals had a low risk for hip fracture before TKR but an increased risk the first year after TKR. The risk in individuals below age 75 years and for trochanteric fractures was increased after TKR. Possible explanations include changed knee kinematics after a TKR, physical activity level, fall risk, and other unknown factors.

Increased risk for hip fracture after death of a spouse-further support for bereavement frailty?

Death of a spouse is associated with poorer physical and mental health. We followed all married individuals, born from 1902 to 1942, during the period from 1987 to 2002, and found that widows and widowers had higher risk for hip fracture, compared with still married women and men. INTRODUCTION: Spousal bereavement can lead to poorer physical and mental health. We aimed to determine whether married women and men had an elevated risk of hip fracture after death of a spouse. METHODS: In a retrospective cohort study, we followed all Swedish married individuals aged 60 to 100 years (n = 1,783,035), from 1987 to 2002. Data are presented as mean with 95% confidence interval (CI). RESULTS: During the follow-up period, 21,305 hip fractures among widows and 6538 hip fractures among widowers were noted. The hazard ratio (HR) for hip fracture in widows compared with married women was 1.34 (95% CI 1.31 to 1.37) and for widowers compared with married men 1.32 (95% CI 1.29 to 1.35). The HR for hip fracture in the first 6 months after death of a spouse was in widows compared with married women 1.62 (95% CI 1.53 to 1.71) and in widowers compared with married men 1.84 (95% CI 1.68 to 2.03). The elevated risk was especially prominent in young widowers in the age range 60-69 years. During the first 6 months they showed a HR of 2.76 (95% CI 1.66 to 4.58) for a hip fractvure compared with age matched married men. Widows aged 60-69 years showed a HR of 1.59 (95% CI 1.26 to 1.99) compared with age matched married women. CONCLUSION: Our observation of a higher hip fracture risk in both genders in connection with the death of a spouse indicates a possible effect of bereavement on frailty.

Handling underlying discrete variables with bivariate mixed hidden Markov models in NONMEM.

Non-linear mixed effects models typically deal with stochasticity in observed processes but models accounting for only observed processes may not be the most appropriate for all data. Hidden Markov models (HMMs) characterize the relationship between observed and hidden variables where the hidden variables can represent an underlying and unmeasurable disease status for example. Adding stochasticity to HMMs results in mixed HMMs (MHMMs) which potentially allow for the characterization of variability in unobservable processes. Further, HMMs can be extended to include more than one observation source and are then multivariate HMMs. In this work MHMMs were developed and applied in a chronic obstructive pulmonary disease example. The two hidden states included in the model were remission and exacerbation and two observation sources were considered, patient reported outcomes (PROs) and forced expiratory volume (FEV1). Estimation properties in the software NONMEM of model parameters were investigated with and without random and covariate effect parameters. The influence of including random and covariate effects of varying magnitudes on the parameters in the model was quantified and a power analysis was performed to compare the power of a single bivariate MHMM with two separate univariate MHMMs. A bivariate MHMM was developed for simulating and analysing hypothetical COPD data consisting of PRO and FEV1 measurements collected every week for 60 weeks. Parameter precision was high for all parameters with the exception of the variance of the transition rate dictating the transition from remission to exacerbation (relative root mean squared error [RRMSE] > 150%). Parameter precision was better with higher magnitudes of the transition probability parameters. A drug effect was included on the transition rate probability and the precision of the drug effect parameter improved with increasing magnitude of the parameter. The power to detect the drug effect was improved by utilizing a bivariate MHMM model over the univariate MHMM models where the number of subject required for 80% power was 25 with the bivariate MHMM model versus 63 in the univariate MHMM FEV1 model and > 100 in the univariate MHMM PRO model. The results advocates for the use of bivariate MHMM models when implementation is possible.

Effects of fibrinogen supplementation on clot formation in blood samples from cardiac surgery patients before and after tranexamic acid administration.

OBJECTIVES: To investigate if supplementation with fibrinogen concentrate to blood samples collected after tranexamic acid administration improve clot formation more than what can be achieved with fibrinogen in the absence of tranexamic acid. BACKGROUND: It is not known if the combination of fibrinogen and tranexamic acid has additional effects than what can be achieved individually. METHODS: Four blood samples were collected from 15 coronary artery bypass patients. Two samples were collected before surgery, before and after 2 g tranexamic acid was administered. The preoperative samples were diluted to haematocrit 21%. Two samples were collected after surgery, before and after a second dose of 2 g tranexamic acid. Fibrinogen concentrate corresponding to a dose of 3 g in a 70-kg patient was added to the samples. Platelet-independent clotting time and maximum clot firmness assessed by thromboelastometry (ROTEM-FIBTEM®) were compared between the samples. RESULTS: Administration of tranexamic acid shortened clotting time marginally (-6%) before surgery, P = 0·029) but did not influence clot firmness. Fibrinogen concentrate shortened clotting time (-14% before and -12% after surgery, both P = 0·003) and increased clot firmness (+51 and +39%, both P < 0·001). The effects of fibrinogen did not differ before and after tranexamic acid administration. Fibrinolysis was not detected in any sample. CONCLUSIONS: The results of this in vitro study suggest that the enhancing effects of fibrinogen on clot firmness in blood samples from cardiac surgery patients are not further increased in the presence of tranexamic acid. Further studies on patients with ongoing bleeding and/or hyperfibrinolysis are necessary to validate the results.

Plant species affects establishment of Escherichia coli O157:H7 gfp+ on leafy vegetables.

AIMS: Greenhouse trials were conducted with different cultivars of baby leaf spinach, rocket and Swiss chard and inoculation of Escherichia coli O157:H7 gfp+, to determine whether plant species and cultivar have an impact on the establishment of this strain. METHODS AND RESULTS: Three cultivars each of spinach, rocket and Swiss chard were spray inoculated with E. coli O157:H7 gfp+ at doses of log 7 CFU per ml. Due to the different lengths of growing period spinach and Swiss chard were spray inoculated three times and rocket five times, with final inoculation performed 3 days prior to harvest. After a growing period of 26-33 days, E. coli O157:H7 gfp+ was recovered from the leaf surface in mean populations between log 1 and 6 CFU per gram. The lowest occurrence of E. coli O157:H7 gfp+ was found on rocket leaves and the highest on spinach. There was no significant difference in the establishment of E. coli O157:H7 gfp+ between cultivars, but there were differences between plant species. Indigenous phyllosphere bacteria were pure cultured and identified with 16S rRNA gene sequencing. CONCLUSIONS: Despite the same high inoculation dose of E. coli O157:H7 gfp+ on leaves, the establishment rate differed between plant species. However, plant cultivar did not affect establishment. Pantoea agglomerans dominated the identified bacterial isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: As previous studies are inconclusive on choice of model plant species and cultivar, we studied whether plant species or cultivar determines the fate of E. coli O157:H7 gfp+ on leafy vegetables. The findings indicate that plant species is a key determinant in the establishment of E. coli O157:H7 gfp+.

Effect of fruit and host fly species on the associative learning by Fopius arisanus.

Parasitoids, released in augmentative biological control programmes, which display a rapid host-location capacity, have a higher likelihood of successfully controlling target pest species. By learning to associate sensory cues to a suitable oviposition site, might parasitoids used as biological control agents, locate hosts more rapidly, and perhaps increase the efficacity of e.g. Tephritidae fruit fly management. We studied associative learning of Fopius arisanus (Hymenoptera: Braconidae) and tested its range of learning in natural and conditional hosts and host fruits, i.e. Bactrocera dorsalis, Zeugodacus cucurbitae, Ceratitis capitata and Ceratitis cosyra (Diptera: Tephritidae) and on fruits (papaya, tomato, banana). Naïve female F. arisanus were compared with experienced wasps, which had been offered infested and non-infested fruit, and been allowed to oviposit. Preferences for olfactory cues from infested fruits were thereafter assessed in a two-choice olfactometer. Naïve and trained parasitoids preference differed in general and non-responders to infested fruits were higher among naïve parasitoids. The trained wasps preferred the fruit infested in the training more than the control fruit, for all combination, except when C. cosyra infested the fruits, hence avoidance behavioural response was observed towards the odour of the infested fruit. Fopius arisanus was capable of behaviourally respond to the learned information, e.g. associative odour learning was achieved, yet limited depending on interaction level, fruit fly and fruit combination. To create F. arisanus preference of an associated odour, it might hence be needed to ensure oviposition in perceived suitable host and host fruit, for the parasitoid learning to become favourable in a biological control setup.

Variations in the vitamin D receptor gene are not associated with measures of muscle strength, physical performance, or falls in elderly men. Data from MrOS Sweden.

The vitamin D receptor (VDR) has been proposed as a candidate gene for several musculoskeletal phenotypes. However, previous results on the associations between genetic variants of the VDR with muscle strength and falls have been contradictory. The MrOS Sweden survey, a prospective population-based cohort study of 3014 elderly men (mean age 75 years, range 69-81) offered the opportunity to further investigate these associations. At baseline, data were collected on muscle strength and also the prevalence of falls during the previous 12 months. Genetic association analysis was performed for 7 Single Nucleotide Polymorphisms (SNPs), covering the genetic region surrounding the VDR gene in 2924 men with available samples of DNA. Genetic variations in the VDR were not associated with five different measurements of muscle strength or physical performance (hand grip strength right and left, 6 m walking test (easy and narrow) and timed-stands test). However, one of the 7 SNPs of the gene for the VDR receptor, rs7136534, was associated with prevalence of falls (33.6% of the AA, 14.6% of the AG and 16.5% of the GG allele). In conclusion, VDR genetic variants are not related to muscle strength or physical performance in elderly Swedish men. The role of the rs7136534 SNP for the occurrence of falls is not clear.