Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Disseminated tuberculosis, CMV viraemia & haemophagocytic-lymphohistiocystosis syndrome in an adult patient with anti- IFNγ autoantibodies - case report and brief review

We report a case of an adult female with disseminated tuberculosis, cytomegalovirus viraemia and haemophagocytic-lymphohistiocystosis syndrome associated with neutralizing anti- interferon gamma (IFNγ) autoantibodies demonstrated by absent IFNγ stimulated STAT1 phosphorylation in the presence of patient sera. A brief review of immunodeficiency caused by anti-IFNγ autoantibodies is also described.

Groundhog Day in the emergency department: A systematic review of 20 years of news coverage in Australia

This study examined how the Australian news media have portrayed public hospital Emergency Departments (EDs) over the last two decades. A systematic review and media frame analysis, searching Factiva and Australia and New Zealand News Stream for digital and print news articles published between January 2000 and January 2020. Eligibility criteria were (1) discussed EDs in public hospitals; (2) the primary focus of the article was the ED; (3) focused on the Australian context; (4) were published by one of the Australian state-based news outlets (e.g., The Sydney Morning Herald, Herald Sun). A pair of reviewers independently screened 242 articles for inclusion according to the pre-established criteria. Discrepancies were resolved via discussion. 126 articles met the inclusion criteria. Pairs of independent reviewers identified frames in 20% of the articles using an inductive approach to develop a framework for coding the remaining articles. News media rely heavily on reporting problems within and with the ED, while also proposing a cause. Praise for EDs was minimal. Opinions were primarily from government spokespeople, professional associations, and doctors. ED performance was often reported as fact, with no reference to the source of the information. Rhetorical framing devices, such as hyperbole and imagery, were used to emphasise dominant themes. The negative bias inherent in news media reporting of EDs could potentially damage public awareness of ED functioning, with implications for the likelihood of the public's accessing ED services. Like in the film Groundhog Day, news media reporting is stuck in a loop reporting the same narrative over and over again.

Associations between oral health and general health: a surveywide association study of the NHANES

OBJECTIVE

This proof of concept study uses data from the National Health and Nutrition Examination Survey (NHANES) to explore potential associations between oral and systemic health in a survey-wide association study (SWAS).

BASIC RESEARCH DESIGN

Data from n=9,971 records in the 2015-2016 NHANES survey were used to evaluate associations between self-rated oral health and the various systemic health conditions that are included in the survey. Associations were estimated using survey-weighted linear regression models adjusted for age, sex, race, and smoking status.

RESULTS

Substantial associations with self-rated oral health were evident after correction for multiple comparisons. The study revealed associations in categories of mental health, cardiovascular disease, and diabetes adding to the body of evidence. The study also suggested associations with physical functioning, vision, hearing, genitourinary symptoms, and the prevalence of hepatitis.

CONCLUSIONS

The SWAS method demonstrated the ability to identify associations between oral health and systemic health. Suggested associations should be investigated further investigated with emphasis on both biologic and societal mechanisms. The noteworthy associations with mental health, physical activity, and cardiovascular disease in this study inform clinicians from each of these disciplines that they may benefit from collaborations with oral health care providers to promote whole-person health.

Multicentre evaluation of Erytra Eflexis®, a benchtop fully automated analyser with a compact design for routine use in blood transfusion laboratory

OBJECTIVES

Evaluation of the compact benchtop Erytra Eflexis® automated analyser was performed at three health centres representing a range of routine transfusion workload.

BACKGROUND

Automation instruments with the simplicity and flexibility adequate for small- to mid-sized blood transfusion services are an unmet need.

METHODS

Performance in pre-transfusion testing (2109 ABO/D, 382 Rh/K phenotype, 2001 antibody screening, 113 antibody identification, 151 DAT, 88 extended phenotype; 655 cross matching) in comparison to Erytra® as reference device was assessed. Throughput [time to first result (TTFR), final turn-around time (TAT), processing rate] was calculated; usability and adaptability in laboratory practice under routine and with emergency samples were surveyed.

RESULTS

Agreement between systems was 99·8% (11/5499 test discrepancies, all due to weak/doubtful positive reactions). Erytra Eflexis produced six true positives (two Rh/D, two B positives, two screening), four false positives (three screening and one cross matching) and one false negative (screening). Processing of eight routine samples with the Erytra Eflexis for ABO/Rh(D) and screening took 34-38 min and 32-37 min, respectively, independent of the simultaneous processing of a STAT sample, whether or not the incubator for STAT was reserved. In this scenario, a STAT sample requested within 2 min after the routine load was processed in 14-26 min. Processing rate tended to stabilise and optimise in the larger workloads, particularly in ABO/Rh(D)/K cards (16·7, 18 and 19·5 results/h for 10, 15 and 24 specimens, respectively).

CONCLUSION

Erytra Eflexis analyser was found to be reliable and suitable for pre-transfusion routine tests performed in a small-/medium-sized blood transfusion laboratory.

Pathogenicity of the bacterium New Zealand rickettsia-like organism (NZ-RLO2) in Chinook salmon Oncorhynchus tshawytscha smolt

Farmed New Zealand Chinook salmon Oncorhynchus tshawytscha Walbaum have been found to be infected by rickettsia-like organisms (NZ-RLO). While these Gram-negative intra-cellular bacteria are closely related to Piscirickettsia salmonis, a significant pathogen for farmed salmon globally, the pathogenicity of NZ-RLO is unknown. The aim of the present study was to determine if one strain, NZ-RLO2, causes disease in Chinook salmon. Post-smolt salmon were inoculated with NZ-RLO2 by intraperitoneal injection at high, medium and low doses and observed for 30 d. All fish in the high and medium dosed groups died by the end of the study and 63% of the low dose group died within 30 d of inoculation. Necropsy revealed the fish inoculated with NZ-RLO2 had internal multifocal haemorrhages. The most consistent histological finding in fish inoculated with NZ-RLO2 was neutrophilic and necrotizing pancreatitis and steatitis with intra-cytoplasmic organisms often visible within areas of inflammation. Other histological lesions included multifocal hepatic necrosis, haematopoietic cell necrosis and splenic and renal lymphoid depletion. The presence of NZ-RLO2 within the inoculated fish was confirmed by replication in cell culture and qPCR. The results suggest NZ-RLO2 can cause disease in Chinook salmon and therefore could be a significant pathogen in farmed Chinook salmon.

Validity of an ultra-wideband local positioning system to measure locomotion in indoor sports

The validity of an Ultra-wideband (UWB) positioning system was investigated during linear and change-of-direction (COD) running drills. Six recreationally-active men performed ten repetitions of four activities (walking, jogging, maximal acceleration, and 45º COD) on an indoor court. Activities were repeated twice, in the centre of the court and on the side. Participants wore a receiver tag (Clearsky T6, Catapult Sports) and two reflective markers placed on the tag to allow for comparisons with the criterion system (Vicon). Distance, mean and peak velocity, acceleration, and deceleration were assessed. Validity was assessed via percentage least-square means difference (Clearsky-Vicon) with 90% confidence interval and magnitude-based inference; typical error was expressed as within-subject standard deviation. The mean differences for distance, mean/peak speed, and mean/peak accelerations in the linear drills were in the range of 0.2-12%, with typical errors between 1.2 and 9.3%. Mean and peak deceleration had larger differences and errors between systems. In the COD drill, moderate-to-large differences were detected for the activity performed in the centre of the court, increasing to large/very large on the side. When filtered and smoothed following a similar process, the UWB-based positioning system had acceptable validity, compared to Vicon, to assess movements representative of indoor sports.

Training in metabolomics research. I. Designing the experiment, collecting and extracting samples and generating metabolomics data

Metabolomics is perhaps the most challenging of the -omics fields, given the complexity of an organism's metabolome and the rapid rate at which it changes. When one sets out to study metabolism there are numerous dynamic variables that can influence metabolism that must be considered. Recognizing the experimental challenges confronting researchers who undertake metabolism studies, workshops like the one at University of Alabama at Birmingham have been established to offer instructional guidance. A summary of the UAB course training materials is being published as a two-part Special Feature Tutorial. In this month's Part I the authors discuss details of good experimental design and sample collection and handling. In an upcoming Part II, the authors discuss in detail the various aspects of data analysis.

Lethal and sub-lethal effects of faecal deltamethrin residues on dung-feeding insects

Endectocides administered to livestock to facilitate pest and parasite control may be excreted in the faeces at concentrations that are toxic to coprophagous insects, including species of ecological importance. Although much research has focused on the effects of macrocyclic lactones, relatively less attention has been given to any similar impacts of the widely used pyrethroid insecticides. Here, the effects of faecal residues of the pyrethroid deltamethrin after application to Holstein-Friesian cattle in a proprietary pour-on formulation are examined. Freshly dropped dung was collected 1, 3, 5 and 7 days after treatment and from an untreated control group. In laboratory bioasssays, female Lucilia sericata (Diptera: Calliphoridae) blow flies matured significantly smaller egg batches and had a lower percentage of eggs hatch after feeding on dung collected for up to 5 days after treatment, compared with flies feeding on dung from untreated cattle. In the field, artificial dung pats were constructed from the collected dung and left on pastureland for 7 days before being retrieved and searched for insects. Significantly more adult Diptera emerged from the faeces of untreated cattle than from the dung of treated cattle collected on days 1 and 3 after treatment. Adult Coleoptera were found in lower numbers in the dung of treated animals compared with control dung, suggesting a repellent effect. The results indicate that deltamethrin residues in cattle faeces have a range of lethal and sub-lethal effects on dung-feeding insects for up to a week after treatment, but that the precise duration and nature of toxicity varies depending on the sensitivity of the insect in question.

Evolving practice: X-linked agammaglobulinemia and lung transplantation

X-linked agammaglobulinemia (XLA) is a rare primary humoral immunodeficiency syndrome characterized by agammaglobulinemia, recurrent infections and bronchiectasis. Despite the association with end-stage bronchiectasis, the literature on XLA and lung transplantation is extremely limited. We report a series of 6 XLA patients with bronchiectasis who underwent lung transplantation. Short-term outcomes were excellent however long-term outcomes were disappointing with a high incidence of pulmonary sepsis and chronic lung allograft dysfunction (CLAD).

Component reductions in oxygen delivery generate variable haemodynamic and stress hormone responses

BACKGROUND

In clinical practice, global oxygen delivery (DO2) is often considered as a whole; however pathological and adaptive responses after a decrease in individual constituents of the DO2 equation (cardiac output, haemoglobin, oxyhaemoglobin saturation) are likely to be diverse. We hypothesized that an equivalent decrease in DO2 after reductions in each separate component of the equation would result in different haemodynamic, tissue oxygenation, and stress hormonal responses.

METHODS

Anaesthetized, fluid-resuscitated male Wistar rats were subjected to circulatory, anaemic, or hypoxic hypoxia (by haemorrhage, isovolaemic haemodilution, and breathing a hypoxic gas mix, respectively), produced either rapidly over 5 min or graded over 30 min, to a targeted 50% decrease in global oxygen delivery. Sham-operated animals acted as controls. Measurements were made of haemodynamics, skeletal muscle tissue oxygen tension, blood gas analysis, and circulating stress hormone levels.

RESULTS

Whereas haemorrhage generated the largest decrease in cardiac output, and the greatest stress hormone response, haemodilution had the most marked effect on arterial pressure. In contrast, rapid hypoxaemia produced a minor impact on global haemodynamics yet induced the greatest decrease in regional oxygenation. A greater degree of hyperlactataemia was observed with graded insults compared with those administered rapidly.

CONCLUSIONS

Decreasing global oxygen delivery, achieved by targeted reductions in its separate components, induces varying circulatory, tissue oxygen tension, and stress hormone responses. We conclude that not all oxygen delivery is the same; this disparity should be emphasized in classical teaching and re-evaluated in patient management.

Imaging the effects of oxygen saturation changes in voluntary apnea and hyperventilation on susceptibility-weighted imaging

BACKGROUND AND PURPOSE

Cerebrovascular oxygenation changes during respiratory challenges have clinically important implications for brain function, including cerebral autoregulation and the rate of brain metabolism. SWI is sensitive to venous oxygenation level by exploitation of the magnetic susceptibility of deoxygenated blood. We assessed cerebral venous blood oxygenation changes during simple voluntary breath-holding (apnea) and hyperventilation by use of SWI at 3T.

MATERIALS AND METHODS

We performed SWI scans (3T; acquisition time of 1 minute, 28 seconds; centered on the anterior commissure and the posterior commissure) on 10 healthy male volunteers during baseline breathing as well as during simple voluntary hyperventilation and apnea challenges. The hyperventilation and apnea tasks were separated by a 5-minute resting period. SWI venograms were generated, and the signal changes on SWI before and after the respiratory stress tasks were compared by means of a paired Student t test.

RESULTS

Changes in venous vasculature visibility caused by the respiratory challenges were directly visualized on the SWI venograms. The venogram segmentation results showed that voluntary apnea decreased the mean venous blood voxel number by 1.6% (P < .0001), and hyperventilation increased the mean venous blood voxel number by 2.7% (P < .0001). These results can be explained by blood CO2 changes secondary to the respiratory challenges, which can alter cerebrovascular tone and cerebral blood flow and ultimately affect venous oxygen levels.

CONCLUSIONS

These results highlight the sensitivity of SWI to simple and noninvasive respiratory challenges and its potential utility in assessing cerebral hemodynamics and vasomotor responses.

An improved genetic system for bioengineering buoyant gas vesicle nanoparticles from Haloarchaea

BACKGROUND

Gas vesicles are hollow, buoyant organelles bounded by a thin and extremely stable protein membrane. They are coded by a cluster of gvp genes in the halophilic archaeon, Halobacterium sp. NRC-1. Using an expression vector containing the entire gvp gene cluster, gas vesicle nanoparticles (GVNPs) have been successfully bioengineered for antigen display by constructing gene fusions between the gvpC gene and coding sequences from bacterial and viral pathogens.

RESULTS

To improve and streamline the genetic system for bioengineering of GVNPs, we first constructed a strain of Halobacterium sp. NRC-1 deleted solely for the gvpC gene. The deleted strain contained smaller, more spindle-shaped nanoparticles observable by transmission electron microscopy, confirming a shape-determining role for GvpC in gas vesicle biogenesis. Next, we constructed expression plasmids containing N-terminal coding portions or the complete gvpC gene. After introducing the expression plasmids into the Halobacterium sp. NRC-1 ΔgvpC strain, GvpC protein and variants were localized to the GVNPs by Western blotting analysis and their effects on increasing the size and shape of nanoparticles established by electron microscopy. Finally, a synthetic gene coding for Gaussia princeps luciferase was fused to the gvpC gene fragments on expression plasmids, resulting in an enzymatically active GvpC-luciferase fusion protein bound to the buoyant nanoparticles from Halobacterium.

CONCLUSION

GvpC protein and its N-terminal fragments expressed from plasmid constructs complemented a Halobacterium sp. NRC-1 ΔgvpC strain and bound to buoyant GVNPs. Fusion of the luciferase reporter gene from Gaussia princeps to the gvpC gene derivatives in expression plasmids produced GVNPs with enzymatically active luciferase bound. These results establish a significantly improved genetic system for displaying foreign proteins on Halobacterium gas vesicles and extend the bioengineering potential of these novel nanoparticles to catalytically active enzymes.

Proton beam scattering system optimization for clinical and research applications

PURPOSE

To develop and test a method for optimizing and constructing a dual scattering system in passively scattered proton therapy.

METHODS

A beam optics optimization algorithm was developed to optimize the thickness of the first scatterer (S1) and the profile (of both the high-Z material and Lexan) of the second scatterer (S2) to deliver a proton beam matching a given set of parameters, including field diameter, fluence, flatness, and symmetry. A new manufacturing process was also tested that allows the contoured second scattering foil to be created much more economically and quickly using Cerrobend casting. Two application-specific scattering systems were developed and tested using both experimental and Monte Carlo techniques to validate the optimization process described.

RESULTS

A scattering system was optimized and constructed to deliver large uniform irradiations of radiobiology samples at low dose rates. This system was successfully built and tested using film and ionization chambers. The system delivered a uniform radiation field of 50 cm diameter (to a dose of ± 7% of the central axis) while the depth dose profile could be tuned to match the specifications of the particular investigator using modulator wheels and range shifters. A second scattering system for intermediate field size (4 cm < diameter < 10 cm) stereotactic radiosurgery and radiation therapy (SRS and SRT) treatments was also developed and tested using GEANT4. This system improved beam efficiency by over 70% compared with existing scattering systems while maintaining field flatness and depth dose profile. In both cases the proton range uniformity across the radiation field was maintained, further indicating the accuracy of the energy loss formalism in the optimization algorithm.

CONCLUSIONS

The methods described allow for rapid prototyping of scattering foils to meet the demands of both research and clinical beam delivery applications in proton therapy.

Liquid chromatography: mass spectrometry of isoflavones

High-performance liquid chromatography (HPLC) or capillary electrophoresis (CE) is particularly suited to the separation and analysis of a wide range of biological compounds. When investigating such compounds in complex matrices (e.g., blood, tissue, urine, foods), specificity of the detection method becomes an important issue. This can be overcome by extensive purification procedures before HPLC or CE analysis, but at the cost of a lot of effort and often unknown losses during the extraction and purification procedures. Such losses can be overcome by the addition of isotopically labeled internal standards, subject to their availability. The coupling of HPLC or CE with mass spectrometry provides a very specific method of detection. Compounds are transferred as ions to the gas phase by two types of spraying technologies, electrospray ionization (ESI) and heated nebulizer-atmospheric pressure chemical ionization. Although the mass-to-charge ratios of the molecular ions can be used to provisionally identify a compound, full confirmation of structure requires collision-induced dissociation and analysis of the resulting fragment ions. Combination of specific parent ion-daughter ion pairs allows for the quantitative measurement of isoflavones in the 1-5 pmol range with coefficients of variation for duplicate samples in the range of 5-9%. CE places greater demands on the mass spectrometer than does HPLC, because it generates narrow peak widths. A mass spectrometer with a scanning quadrupole analyzer does not enable full exploitation of the power of CE; in this context, an instrument with an ESI interface and a time-of-flight analyzer is ideal.

Antioxidant properties of phytoestrogens

The oxidation of lipids is an autocatalytic process consisting of a number of well-defined interrelated chemical reactions. Its importance has long been recognized in the food and polymer industry, and recent advances in the understanding of vascular diseases have shown that lipid peroxidation also contributes to human disease. The various chemical stages of the reaction offer several therapeutic targets for inhibition, and from the structural characteristics of phytoestrogens it is anticipated that they should exhibit antioxidant properties. Alone, it is not sufficient for compounds such as the phytoestrogens to exhibit biological activity as antioxidants; the criteria that should be satisfied for this mechanism to be relevant biologically are discussed.

Isoflavone metabolism in domestic cats (Felis catus): comparison of plasma metabolites detected after ingestion of two different dietary forms of genistein and daidzein

Some felid diets contain isoflavones but the metabolic capacity of cats toward isoflavones is relatively unknown, despite the understanding that isoflavones have divergent biological potential according to their metabolite end products. The objective of this study was to determine the plasma metabolites detectable in domestic cats after exposure to 2 different dietary forms of isoflavones, either as a soy extract tablet (n = 6) or as part of a dietary matrix (n = 4). Serial blood samples were collected after isoflavone exposure to identify the plasma metabolites of each cat. Genistein was detected in its unconjugated form or as a monosulfate. Daidzein was detected as both a mono- and disulfate as well as in its unconjugated form. Other daidzein metabolites detected included equol mono- and disulfate, dihydrodaidzein, and O-desmethylangolensin. No β-glucuronide metabolites of either isoflavone were detected. Equol was produced in markedly fewer cats after ingestion of a soy extract tablet as a single oral bolus compared with cats consuming an isoflavone-containing diet. The detectable metabolites of the isoflavones, genistein and daidzein, in domestic cat plasma after dietary ingestion has been described in the present study for the first time. The metabolic capacity for isoflavones by domestic cats appears to be efficient, with only minimal proportions of the ingested amount detected in their unconjugated forms. This has implications for the potential of isoflavones to exert physiological activity in the domestic cat when consumed at concentrations representative of typical dietary intake.

SU-E-T-232: Proton Source Modeling for Geant4 Monte Carlo Simulations

PURPOSE

To investigate the effect of initial proton beam source placement, distribution and angle on the proton dose distribution in a therapeutic nozzle using Geant4.

METHODS

We performed Geant4 Monte Carlo simulations of a passively scattered proton treatment nozzle. Accurate geometry including all elements in the treatment room was used. Protons were generated just inside the vacuum pipe using one of two models. First, a standard two dimensional Gaussian distribution of proton starting position was used with a small random angle added to the initial direction. The size of the Gaussian distribution and the random angle were set to match measured beam spot size and angular spread at the exit window. Second, a point source of protons further back in the vacuum pipe with a small random angle was used. The distance of the point source to exit window and the random angle were set to match the spot size and angular deviation used for the Gaussian distribution. Depth dose curves and orthogonal beam profiles were examined to determine changes between the two models.

RESULTS

Orthogonal beam profiles for large apertures showed changes of up to 6.5% between the two models with the point source showing much better agreement with measured data. Depth dose curves and orthogonal profiles for small apertures were unaffected. For large apertures, the average difference compared to measured data was of 1.9% and 0.7% and the max difference was 5.0% and 1.6% for Gaussian and point sources, respectively.

CONCLUSIONS

The point source more realistically models the proton distribution in the vacuum pipe by correlating the proton position with the direction. For certain scattering setups and large apertures point source modeling is necessary to accurate match measured data with Monte Carlo simulations.

Do hospital visitors wash their hands? Assessing the use of alcohol-based hand sanitizer in a hospital lobby

BACKGROUND

Reports regarding hand hygiene compliance (HHC) among hospital visitors are limited. Although there is an implicit assumption that the availability of alcohol-based hand sanitizer (AHS) promotes visitor HHC, the degree of AHS use by visitors remains unclear. To assess AHS use, we observed visitor HHC and how it is affected by visual cues in a private university hospital.

METHODS

Using an observational controlled study, we tested 3 interventions: a desk sign mandating all visitors to use AHS, a free-standing AHS dispenser directly in front of a security desk, and a combination of a freestanding AHS dispenser and a sign.

RESULTS

HHC was 0.52% at baseline and did not improve significantly when the desk sign was provided as a cue 0.67% (P = .753). However, HHC did improve significantly with use of the freestanding AHS dispenser (9.33%) and the sign and dispenser combination (11.67%) (P < .001 for all comparisons of dispenser alone and sign and dispenser with baseline and sign alone). The degree of improvement with the sign and dispenser combination over the dispenser was not statistically significant.

CONCLUSIONS

Hospital visitors represent an important factor in infection prevention. A coordinated effort is needed to increase visitor HHC, including an evaluation of the AHS placement, education of visitors on the importance of HHC, and evaluation of corresponding changes in hand hygiene behavior.

Actinomyces turicensis infection mimicking ovarian tumour

This case report explores an unusual presentation of a commensal organism, Actinomyces, which mimicked a presentation of ovarian cancer. A 73-year-old woman presented to a tertiary level hospital with persistent left iliac fossa abdominal pain, anorexia and fever lasting over one week, with a three-month history of bright rectal bleeding. Imaging was suggestive of malignancy. Fine needle aspiration of an enlarged lymph node was non-diagnostic. Blood cultures taken at presentation became positive after two days for Gram-positive rods, which were most likely Actinomyces. The patient was treated with penicillin 1.8 g four hourly with rapid improvement. Actinomycosis is frequently misdiagnosed as malignancy initially due to its relatively indolent course. Lesions often resolve with antibiotics, without the need for surgical intervention.

Antiresorptive effects of phytoestrogen supplements compared with estradiol or risedronate in postmenopausal women using (41)Ca methodology

INTRODUCTION

Reduction of ovarian estrogen secretion at menopause increases net bone resorption and leads to bone loss. Isoflavones have been reported to protect bone from estrogen deficiency, but their modest effects on bone resorption have been difficult to measure with traditional analytical methods.

METHODS

In this randomized-order, crossover, blinded trial in 11 healthy postmenopausal women, we compared four commercial sources of isoflavones from soy cotyledon, soy germ, kudzu, and red clover and a positive control of oral 1 mg estradiol combined with 2.5 mg medroxyprogesterone or 5 mg/d oral risedronate (Actonel) for their antiresorptive effects on bone using novel (41)Ca methodology.

RESULTS

Risedronate and estrogen plus progesterone decreased net bone resorption measured by urinary (41)Ca by 22 and 24%, respectively (P < 0.0001). Despite serum isoflavone profiles indicating bioavailability of the phytoestrogens, only soy isoflavones from the cotyledon and germ significantly decreased net bone resorption by 9% (P = 0.0002) and 5% (P = 0.03), respectively. Calcium absorption and biochemical markers of bone turnover were not influenced by interventions.

CONCLUSIONS

Dietary supplements containing genistein-like isoflavones demonstrated a significant but modest ability to suppress net bone resorption in postmenopausal women at the doses supplied in this study over a 50-d intervention period.

Barriers to advance care planning in chronic obstructive pulmonary disease

The English End of Life Care Strategy promises that all patients with advanced, life limiting illness will have the opportunity to participate in Advance Care Planning (ACP). For patients with Chronic Obstructive Pulmonary Disease (COPD), the barriers to this being achieved in practice are under-explored. Five focus groups were held with a total of 39 health care professionals involved in the care of patients with COPD. Participants reported that discussions relating to ACP are very rarely initiated with patients with COPD and identified the following barriers: inadequate information provision about the likely course of COPD at diagnosis; lack of consensus regarding who should initiate ACP and in which setting; connotations of comparing COPD with cancer; ACP discussions conflicting with goals of chronic disease management; and a lack of understanding of the meaning of 'end of life' within the context of COPD. The findings from this study indicate that, for patients with COPD, significant service improvement is needed before the objective of the End of Life Care Strategy regarding patient participation in end of life decision-making is to be achieved. Whilst the findings support the Strategy's recommendations regarding an urgent for both professional education and increased public education about end of life issues, they also indicate that these alone will not be enough to effect the level of change required. Consideration also needs to be given to the integration of chronic disease management and end of life care and to developing definitions of end of life care that fit with concepts of 'continuous palliation'.