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.

Spatially resolved diagnostics for optimization of large ion beam sources

Giant negative ion sources for neutral beam injectors deliver huge negative ion currents, thanks to their multi-beamlet configuration. As the single-beamlet optics defines the transmission losses along the beamline, the extraction of a similar current for all beamlets is extremely desirable, in order to facilitate the beam source operation (i.e., around perveance match). This Review investigates the correlation between the vertical profile of beam intensity and the vertical profiles of plasma properties at the extraction region of the source, focusing on the influence of increasing cesium injection. Only by the combined use of all available source diagnostics, described in this Review, can beam features on the scale of the non-uniformities be investigated with a sufficient space resolution. At RF power of 50 kW/driver, with intermediate bias currents and a filter field of 2.4 mT, it is found that the central part of the four vertical beam segments exhibits comparable plasma density and beamlet currents; at the edges of the central segments, both the beam and electron density appear to decrease (probably maintaining fixed electron-to-ion ratio); at the bottom of the source, an increase of cesium injection can compensate for the vertical drifts that cause a much higher presence of electrons and a lower amount of negative ions.

Effectiveness of fascial closure technique following percutaneous endovascular aneurysm repair

INTRODUCTION

Percutaneous access and closure is commonly performed for patients undergoing endovascular aneurysm repair (EVAR). It has proven to be a safe and successful method of closure associated with fewer complications when compared with the traditional open technique. Fascial closure is an alternative technique that can be used for closure reducing the risks associated with the open technique. The aim of this study was to assess the safety and durability of fascial closure for failed percutaneous closure device following EVAR.

MATERIALS AND METHODS

Over a 12-month period, 49 patients who had undergone EVAR were identified via our EVAR register. Retrospective analysis of the clinical records was undertaken. We identified all the patients who had fascial closure of the groins following a failed percutaneous closure device. Patients had a computed tomography angiogram one month postoperatively, with duplex imaging and clinic follow-up three months later.

RESULTS

Fascial closure was performed in 14 groins. It failed in three groins and these patients had traditional open repair. Fascial closure was successful in 11 groins (7 patients). Of these seven patients, one was female (6%). The mean age was 80 years (range 68-92 years). Two patients died and one was lost to follow-up. One pseudoaneurysms were seen on computed tomography angiogram, which was managed conservatively and had resolved on follow-up imaging.

CONCLUSIONS

Fascial closure is a very good alternative to open repair after failure of the closure device.

Fatal Pulmonary Embolism following Hip and Knee Replacement. A Study of 2153 Cases Using Routine Mechanical Prophylaxis and Selective Chemoprophylaxis

In order to prevent fatal pulmonary embolism, TED stockings, foot pumps and early mobilisation on the second post-operative day are used at our centre. Only patients deemed to be high risk (previous DVT/PE or obese) are given clexane as inpatients and warfarin for six weeks postop. From the hospital database 1137 primary total hip replacements and 1017 primary total knee replacements were identified and the figures were confirmed with the theatre implant order books. The cause of death for those patients on the database, now deceased, was obtained from the coroner. Where a postmortem had not been performed the patient was assumed to have died of a PE. Within three months of surgery, a fatal PE rate of 0.09% (95% CI 0.00–0.26%) following hip replacement and 0.20% (95% CI 0.00–0.46%) after knee replacement was found. Thirty-four patients had been discharged on warfarin according to the pharmacy records. We would therefore not recommend the routine use of chemical thromboprophylaxis following joint replacement.

Associations between gender and outcome of acute psychiatric admission, looking specifically at length of stay and type of admission

Introduction

There is little published data regarding the association between gender and outcomes in acute inpatient psychiatry. We present outcomes from a study of 5601 acute psychiatric admissions.

Objective

The objective of this study was to identify associations between gender and outcome of acute psychiatric admission, looking specifically at length of stay and at whether they were detained in hospital.

Methods

The relationship between gender and acute psychiatric inpatient length of stay and detention status was analyzed for all admissions over 90 months from Sept 2002 to Feb 2010. There were 5601 consecutive admissions included in this study, 2862 of which were male and 2739 were female. There were no exclusions. Data was complete for more than 99% of subjects, and was extracted from part of routine service data on an anonymous- basis. The subjects were admitted into two acute inpatient wards in central Norfolk. Data was analyzed using SPSS. Ethics consent was granted by the research ethics committee.

Results

The study showed no significant difference in average length of stay (female = 32.98, male = 32.11; P = 0.595). Additionally, no significant difference was found linking gender to detention status (26% female, 25% male; P = 0.517) as opposed to informal or voluntary admission.

Conclusion

The study found no evidence of a gender bias regarding overall length of stay and legal status in acute admissions. Further research should be conducted in this area to examine whether there is any gender bias in outcomes relating to diagnosis.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

A 3 year minimum follow up of Endoprosthetic replacement for distal femoral fractures - An alternative treatment option

INTRODUCTION

Although the use of an endoprosthesis for distal femoral fractures remains a valid treatment option the widespread use is in its infancy.

METHODOLOGY

In this retrospective case series, we review cases of distal femoral fracture treated with endoprosthetic replacement (EPR). The outcomes we assessed were the time to start mobilising, the time to discharge, morbidity and mortality as well as an Oxford knee score to assess pain and function and also the early survivorship. 6 of the 11 from the cohort had existing Total Knee Replacements (TKRs) in situ.

RESULTS

There were 11 knees in our cohort with a mean age of 81.5 years (range 52-102 years). The median time to follow up was 3.5 years (range 1.6 to 5.5 years). The median times to theatre was 3 days and to discharge was 16 days. Oxford functional and pain scores were 32/48.

DISCUSSION

In the appropriate patient and fracture pattern, Endoprosthetic knee replacement is an excellent option in the treatment of distal femoral fractures whether associated with an existing TKR or not. The implant is more costly than traditional open reduction and internal fixation, but the earlier return to full mobility post-operatively may save on hospital/care home stay and free up hospital space and minimise complications.

The North Wyke Farm Platform: effect of temperate grassland farming systems on soil moisture contents, runoff and associated water quality dynamics

The North Wyke Farm Platform was established as a United Kingdom national capability for collaborative research, training and knowledge exchange in agro-environmental sciences. Its remit is to research agricultural productivity and ecosystem responses to different management practices for beef and sheep production in lowland grasslands. A system based on permanent pasture was implemented on three 21-ha farmlets to obtain baseline data on hydrology, nutrient cycling and productivity for 2 years. Since then two farmlets have been modified by either (i) planned reseeding with grasses that have been bred for enhanced sugar content or deep-rooting traits or (ii) sowing grass and legume mixtures to reduce nitrogen fertilizer inputs. The quantities of nutrients that enter, cycle within and leave the farmlets were evaluated with data recorded from sensor technologies coupled with more traditional field study methods. We demonstrate the potential of the farm platform approach with a case study in which we investigate the effects of the weather, field topography and farm management activity on surface runoff and associated pollutant or nutrient loss from soil. We have the opportunity to do a full nutrient cycling analysis, taking account of nutrient transformations in soil, and flows to water and losses to air. The NWFP monitoring system is unique in both scale and scope for a managed land-based capability that brings together several technologies that allow the effect of temperate grassland farming systems on soil moisture levels, runoff and associated water quality dynamics to be studied in detail.

HIGHLIGHTS

Can meat production systems be developed that are productive yet minimize losses to the environment?The data are from an intensively instrumented capability, which is globally unique and topical.We use sensing technologies and surveys to show the effect of pasture renewal on nutrient losses.Platforms provide evidence of the effect of meteorology, topography and farm activity on nutrient loss.

Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a systematic literature review

The objective of the study was to review the literature reporting visual disturbance (VD)following sclerotherapy for varicose veins. Underlying mechanisms will be discussed. A literature search of the databases Medline and Google Scholar was performed. Original articles including randomized trials, case series and case reports reporting VD in humans following sclerotherapy for varicose veins were included. Additional references were also obtained if they had been referenced in related publications. The search yielded 4948 results of which 25 reports were found to meet the inclusion criteria. In larger series with at least 500 included patients the prevalence of VD following sclerotherapy ranges from 0.09% to 2%. In most reports foam sclerotherapy was associated with VD (19); exclusive use of liquid sclerosant was reported in two cases, some reports included foam and liquid sclerosant (4). There were no persistent visual disorders reported. VD occurred with polidocanol and sodium tetradecyl sulphate in different concentrations (0.25–3%). Various forms of foam preparation including various ways of foam production and the liquid –air ratio (1 or 2 parts of liquid mixed with 3, 4 or 5 parts of air) were reported in association with the occurrence of VD. VDs following sclerotherapy for varicose veins are rare and all reported events were transient. Bubble embolism or any kind of embolism seems unlikely to be the only underlying mechanism. A systemic inflammatory response following sclerotherapy has been suggested. Further research to clarify the mechanism of action of sclerosants is required.

Localization and expression of CaBP1/caldendrin in the mouse brain

Ca(2+) binding protein 1 (CaBP1) and caldendrin are alternatively spliced variants of a subfamily of CaBPs with high homology to calmodulin. Although CaBP1 and caldendrin regulate effectors including plasma membrane and intracellular Ca(2+) channels in heterologous expression systems, little is known about their functions in vivo. Therefore, we generated mice deficient in CaBP1/caldendrin expression (C-KO) and analyzed the expression and cellular localization of CaBP1 and caldendrin in the mouse brain. Immunoperoxidase labeling with antibodies recognizing both CaBP1 and caldendrin was absent in the brain of C-KO mice, but was intense in multiple brain regions of wild-type mice. By Western blot, the antibodies detected two proteins that were absent in the C-KO mouse and consistent in size with caldendrin variants originating from alternative translation initiation sites. By quantitative PCR, caldendrin transcript levels were far greater than those for CaBP1, particularly in the cerebral cortex and hippocampus. In the frontal cortex but not in the hippocampus, caldendrin expression increased steadily from birth. By double-label immunofluorescence, CaBP1/caldendrin was localized in principal neurons and parvalbumin-positive interneurons. In the cerebellum, CaBP1/caldendrin antibodies labeled interneurons in the molecular layer and in basket cell terminals surrounding the soma and axon initial segment of Purkinje neurons, but immunolabeling was absent in Purkinje neurons. We conclude that CaBP1/caldendrin is localized both pre- and postsynaptically where it may regulate Ca(2+) signaling and excitability in select groups of excitatory and inhibitory neurons.

Cost effectiveness of nitrate leaching mitigation measures for grassland livestock systems at locations in England and Wales

As much as 60% of the nitrate in water in England is thought to derive from agriculture. Legislation aims to improve water quality by limiting nitrate concentration in surface and groundwaters to 50 mg l(-1). The UK Government responded to the requirements of the EC Nitrate Directive by delineating Nitrate Vulnerable Zones (NVZs) to cover 55% of England in 2002 and increased it to 70% in 2009. In this study we assessed the cost-effectiveness of measures for implementation in livestock systems to mitigate nitrate leaching in the UK. These estimates were prepared for a range of hypothetical farms representative of typical dairy, beef and sheep farms at different locations in England and Wales and for a list of mitigation measures identified to reduce leaching. The NGAUGE and NFixCycle models were used to estimate leaching from these systems. The costs of implementation of the mitigation measures were also assessed in order to evaluate the cost-effectiveness of these measures. In general, the most effective measures to reduce leaching for all systems were the ones that involved a reduction in stocking rates and grazing time, followed by those involving improvements in fertiliser and crop management. Only in the case of the dairy system was effectiveness affected by location of the farm. The costs for implementation in the sheep system were relatively low compared with beef and dairy systems. Implementation of some of the measures with high cost-effectiveness would need to be incentivised financially or with legislation due to the high costs involved.

The 2008 ICOH Workshop on Skin Notation

BACKGROUND

On 29 March 2008 the International Commission on Occupational Health (ICOH) Scientific Committee on Occupational and Environmental Dermatoses organized a Skin Notation Workshop hosted by the 11th International Percutaneous Penetration Perspectives Conference (La Grande Motte, France). Skin notation (S) was chosen as a topic for discussion because this is the only example of existing regulation in the field of dermal risk assessment. The issue was discussed in a previous workshop held in Siena, Italy in 2006 with the objective of focussing on the problems related to S, the different assignment criteria and the attempts to improve the S system made by various international and governmental agencies. A position paper was subsequently published.

OBJECTIVES

The workshop in France was a continuation of this activity with the aim of evaluating how the different strategies can improve S.

METHODS AND DISCUSSION

The Workshop was divided into two sessions. The first was dedicated to lectures focused on different aspects of S. In the second session participants discussed key issues with the aim of exploring the actions needed to improve international S. systems.

Mass balance of the Antarctic ice sheet

The Antarctic contribution to sea-level rise has long been uncertain. While regional variability in ice dynamics has been revealed, a picture of mass changes throughout the continental ice sheet is lacking. Here, we use satellite radar altimetry to measure the elevation change of 72% of the grounded ice sheet during the period 1992-2003. Depending on the density of the snow giving rise to the observed elevation fluctuations, the ice sheet mass trend falls in the range -5-+85Gtyr-1. We find that data from climate model reanalyses are not able to characterise the contemporary snowfall fluctuation with useful accuracy and our best estimate of the overall mass trend-growth of 27+/-29Gtyr-1-is based on an assessment of the expected snowfall variability. Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica. The result exacerbates the difficulty of explaining twentieth century sea-level rise.

Forward surgery on Operation Telic--Iraq 2003

Two Air Assault Surgical Groups (AASGs) from 16 Close Support Medical Regiment deployed to Kuwait on Operation Telic in February 2003. Each AASG was comprised of a four-table resuscitation facility, a two table FST and a twin-bedded ITU facility. An A+E Consultant and nurse, an experienced radiographer and laboratory technician with two further RGNs and CMTs provided resuscitation support. Each FST had an orthopaedic and a general surgeon, two anaesthetists and eight operating department practitioners. Further equipment consisted of a Polymobil 111 X-ray unit, a Sonosite 180 ultrasound scanner and an ISTAT gas, haematocrit and electrolyte analyser. 100 units of mixed blood were carried by each AASG. Fifty-one surgical procedures were performed on thirty one patients. Twenty one of these patients were Iraqi prisoners of war or civilians. Seventeen wound debridements, five amputations, five laparotomies, four insertions of Denham pins with Thomas splintage for femoral fracture, three external fixations and one axillary artery repair formed the basis of the major cases undertaken. The first field use of activated factor VII by the British Army was successful in the resuscitation of a patient with exsanguinating haemorrhage after an open-book (APC-III) pelvic fracture and a ruptured intrapelvic haematoma. The other cases included eleven manipulations under anaesthetic/application of plaster and four finger terminalisations. Forward military surgery has a continued role to play on the modern fast moving battlefield. 16 Close Support Medical Regiment normally supports 16 Air Assault Brigade with its remit for expeditionary operations and SF support. Its experience on Op Telic should influence planning for future deployment.

Helicobacter pylori in children is strongly associated with poverty

BACKGROUND AND AIMS

To examine the association between prevalence of H. pylori colonisation and social deprivation in a sample of children investigated in hospital.

METHODS

A retrospective review of the hospital records of all children (n = 626) who underwent 13C-urea breath testing for suspected H. pylori infection at the Royal Hospital for Sick Children, Glasgow, Scotland between August 1995 to December 2002 was performed. Prevalence of H. pylori colonisation was measured by the 13C-urea breath test and socioeconomic status was measured by the Carstairs and Morris index of deprivation.

RESULTS

The overall prevalence of H. pylori was 26%. There was a highly significant positive association between H. pylori colonisation and poor socioeconomic status (p < 0.000). The prevalence of colonisation was significantly higher in children from the most deprived areas (DepCat 6 and 7; 34%) compared to children from intermediate (DepCat 3 to 5; 22%) and the most affluent areas (DepCat 1 and 2; 16%) (p < 0.0001).

CONCLUSIONS

Socioeconomic deprivation in childhood is associated with a high prevalence of H. pylori colonisation. While the incidence of H. pylori may be declining, it remains common in poor families. If the prevalence of H. pylori (26%) in this selected group reflects that of the population at large, then over 9000 (5%) of Glasgow's children are at risk of this preventable disease. In a city where the majority of adults are colonised with H. pylori, colonisation in early life adds to the burden of health risks to which deprived children are exposed.

Esomeprazole 20 mg on-demand is more acceptable to patients than continuous lansoprazole 15 mg in the long-term maintenance of endoscopy-negative gastro-oesophageal reflux patients: the COMMAND Study

BACKGROUND

Symptom relief, through adherence to appropriate maintenance therapy, is the sole objective of treatment for patients with endoscopy-negative gastro-oesophageal reflux disease.

AIM

To compare the efficacy of 'on-demand' treatment with esomeprazole 20 mg vs. continuous treatment with lansoprazole 15 mg daily in patients with endoscopy-negative gastro-oesophageal reflux disease.

METHODS

Endoscopy-negative gastro-oesophageal reflux disease patients who achieved complete resolution of heartburn after short-term (2-4 weeks) treatment with esomeprazole 20 mg (n = 774) were randomized to receive either esomeprazole 20 mg on-demand (n =311) or lansoprazole 15 mg continuous daily treatment (n = 311) for 6 months.

RESULTS

Significantly more patients were willing to continue taking esomeprazole on-demand than lansoprazole continuous therapy after 6 months (93% vs. 88%; P = 0.02). This superior outcome was achieved despite patients on esomeprazole requiring medication only 38% as often as those on lansoprazole, leading to direct cost savings of more than one-third (36%). Furthermore, patients receiving esomeprazole 20 mg on-demand were more satisfied with their treatment after 1 month compared with patients taking lansoprazole 15 mg continuously.

CONCLUSIONS

In patients with endoscopy-negative gastro-oesophageal reflux disease, esomeprazole 20 mg on-demand is more acceptable to patients and is an economically more effective treatment than lansoprazole 15 mg continuously.

Maternal docosahexaenoic acid supplementation during pregnancy and visual evoked potential development in term infants: a double blind, prospective, randomised trial

AIM

To test the hypothesis that maternal docosahexaenoic acid (DHA) supplementation during pregnancy enhances maturation of the visual evoked potential (VEP) in healthy term infants.

METHODS

One hundred women were supplemented with either fish oil capsules rich in DHA (n = 50) or placebo capsules (n = 50) from week 15 of pregnancy until delivery. Total fatty acids in red blood cells and plasma were measured at weeks 15, 28, and 40 of pregnancy and at delivery in umbilical cord blood. Infant visual pathway development was assessed using VEPs recorded to flash stimuli shortly after birth and to both flash and pattern-reversal stimuli at 50 and 66 weeks post-conceptional age (PCA).

RESULTS

Maternal supplementation did not significantly elevate the level of DHA in umbilical cord blood. Moreover, there were no significant differences in any of the VEP measures observed between supplementation groups. However, maturity of the pattern-reversal VEP at 50 and 66 weeks PCA was associated with DHA status of the infants at birth. Infants with higher DHA status, both as a concentration and as a percentage of total fatty acids, showed shorter P100 peak latencies of the pattern-reversal VEP than those with lower DHA status.

CONCLUSIONS

Maternal DHA supplementation during pregnancy did not enhance VEP maturation in healthy term infants. However, these results show an association between the DHA status of infants at term and early postnatal development of the pattern-reversal VEP, suggesting that DHA status itself may influence maturation of the central visual pathways.

The CATH database: an extended protein family resource for structural and functional genomics

The CATH database of protein domain structures (http://www.biochem.ucl.ac.uk/bsm/cath_new) currently contains 34 287 domain structures classified into 1383 superfamilies and 3285 sequence families. Each structural family is expanded with domain sequence relatives recruited from GenBank using a variety of efficient sequence search protocols and reliable thresholds. This extended resource, known as the CATH-protein family database (CATH-PFDB) contains a total of 310 000 domain sequences classified into 26 812 sequence families. New sequence search protocols have been designed, based on these intermediate sequence libraries, to allow more regular updating of the classification. Further developments include the adaptation of a recently developed method for rapid structure comparison, based on secondary structure matching, for domain boundary assignment. The philosophy behind CATHEDRAL is the recognition of recurrent folds already classified in CATH. Benchmarking of CATHEDRAL, using manually validated domain assignments, demonstrated that 43% of domains boundaries could be completely automatically assigned. This is an improvement on a previous consensus approach for which only 10-20% of domains could be reliably processed in a completely automated fashion. Since domain boundary assignment is a significant bottleneck in the classification of new structures, CATHEDRAL will also help to increase the frequency of CATH updates.

Can attention select only a fixed number of objects at a time?

Several previous studies have suggested that we may attend only a fixed number of 'objects' at a time. However, whereas findings from two-target experiments suggest that we can attend only one object at a time, other results from object-tracking and enumeration paradigms point instead to a four-object limit. Here, we note that in these previous studies the number of objects covaried with the overall size and complexity of the stimulus, such that apparent one-object or four-object limits in those tasks may reflect changes in the complexity of attended stimuli, rather than the number of objects per se. Accordingly, in the current experiments we employ stimuli in which the number of objects varies, while overall size and complexity are held constant. Using these refined measures of object-based effects, we find no evidence for a one-object or four-object limit on attention. Indeed, we conclude that the number of attended objects does not affect how efficiently we can attend a given stimulus. We propose and test an alternative approach to object-based attention limitations based on within-object and between-object feature-binding mechanisms in human vision.

In vivo analysis of porcine endogenous retrovirus expression in transgenic pigs

Xenotransplantation offers a potential solution to the shortage of donor organs for allotransplantation. In vitro studies that demonstrate the transmission of porcine endogenous retroviruses (PERV) from porcine cells to human cells and cell lines have raised concerns regarding the potential transmission of PERV to both xenograft recipients and their contacts (1-4). While no evidence of infection has been detected in any patients who have been treated with a variety of different porcine tissues (5-8), two studies have shown that severe combined immunodeficient (SCID) mice can be infected by PERV after the transplantation of porcine islets (9-10). To further address the concerns of PERV, expression of this virus in tissues and serum from transgenic pigs that express human decay accelerating factor was investigated. Although viral mRNA expression was detected in a variety of tissues, no evidence of viral release was observed in any of the porcine tissues analyzed by transmission electron microscopy. Analysis of porcine serum using the product-based reverse transcriptase assay suggested that virions may be present in porcine serum from large white pigs. However, using methods based on those previously described by Wilson et al. (4), infectious virus was not detected when activated peripheral blood mononuclear cells from these pigs were cocultivated with human cells known to be permissive for PERV.

Scrapie removal using Planova virus removal filters

As a possible method for reducing the risk of transmissible spongiform encephalopathy (TSE) infection, Planova virus removal filters were tested for their ability to remove scrapie agent ME7. Albumin solution was spiked with high-titre ME7 and filtered through three different pore sizes of Planova filters. Infectivity of the pre- and post-filtration samples was assayed in log dilutions by intracerebral inoculation into C57B1/6 mice. Filtration of albumin solution in the absence or presence of a detergent (Sarkosyl) with Planova 35N (35+/-2 nm mean pore size) removed the contaminating scrapie agent with reduction factors of 4.93 log10 and 1.61 log10, respectively. Filtration, both in the absence and presence of detergent with Planova 15N (15+/-2 nm mean pore size), and in the presence of detergent with Planova 10N (9+/-2 nm mean pore size), showed high levels of scrapie reduction of >5.87 log10, >4.21 log10, and >3.80 log10, respectively, with no residual infectively detected in any of the filtrate samples. The effectiveness of Planova 35N filtration for the removal of infectivity of this TSE agent is greatly reduced in the presence of a strong detergent, but Planova filters with 15 nm or smaller pore size membranes can remove such infectivity at high reduction rates.

Inland thinning of Pine Island Glacier, West Antarctica

The Pine Island Glacier (PIG) transports 69 cubic kilometers of ice each year from approximately 10% of the West Antarctic Ice Sheet (WAIS). It is possible that a retreat of the PIG may accelerate ice discharge from the WAIS interior. Satellite altimetry and interferometry show that the grounded PIG thinned by up to 1.6 meters per year between 1992 and 1999, affecting 150 kilometers of the inland glacier. The thinning cannot be explained by short-term variability in accumulation and must result from glacier dynamics.