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.

Post-mortem computed tomography in the investigation of conflict and terrorist related deaths: UK military experience of developing a multidisciplinary service

This paper discusses the introduction, development and utility of post-mortem imaging relating specifically to conflict-related and terrorist-related deaths and considers the use of computed tomography (CT) in the investigations. We demonstrate how a multi-disciplinary approach involving direct communication between forensic pathologist and radiologist can maximise evidential yield, reduce the need for unnecessary dissection and further our understanding of such injuries. This summarises our shared experience of hundreds of cases, each having been individually discussed and reviewed, and has helped shape our understanding of conflict injury as well as contributing to the development of mitigation strategies and adaptations to protective equipment. A series of clinical cases are presented to demonstrate some of the strengths and weaknesses of the process.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

Incidence, Natural History and Risk Factors of Deep Vein Thrombosis in Elective Knee Arthroscopy

Aims: to determine the incidence, anatomical distribution and extent of deep vein thrombosis (DVT) in limbs undergoing elective unilateral knee arthroscopy without active prophylaxis, to evaluate its effect on venous function following early diagnosis, and to quantify the impact of risk factors on its incidence. Methods: 102 consecutive patients undergoing unilateral knee arthroscopy without prophylaxis were studied. A history was obtained with emphasis on the risk factors for thromboembolism, and physical examination and colour duplex were performed prior to and within a week after surgery. Patients who developed calf DVT were given aspirin (150 mg) and compression stockings; those with proximal DVT were admitted for anticoagulation (heparin followed by warfarin). Follow-up (mean 118 [range 84-168] days) entailed weekly physical and duplex examinations during the first month and monthly thereafter. Results: 8 patients developed calf DVT in the operated leg (incidence 7.84% [95% Cl: 2.7%-13.2%]); thrombosis was asymptomatic in 4 of those (50%), caused calf tenderness in 4 (50%) and a positive Homan’s sign in one (12.5%). DVT occurred in the following veins: peroneal 4 subjects (50%), soleal 4 (50%), gastrocnemial 2 (25%) and tibial 2 (25%). Propagation of a calf DVT to the popliteal vein was identified in 1 patient (12.5%). After a median period of 118 days, total clot lysis was found in 50% of DVTs, with partial thrombus resorption in the rest; reflux in the thrombosed veins was present in 75% of limbs with DVT. 43% of patients had 1 risk factor for DVT and 20% had ≥2. The incidence of DVT was higher amongst those with two or more risk factors for thromboembolism (p <.05) or those with previous thrombosis alone (p <.005). Symptoms or signs of pulmonary embolism were not documented. Conclusions: Elective unilateral knee arthroscopy performed without prophylaxis is complicated by ipsilateral calf DVT in 7.8% (95% CI: 2.7%-13.2%) of cases. The risk is higher in the presence of previous thrombosis (relative risk: 8.2) and two or more risk factors for DVT (relative risk: 2.94). Thrombosis may propagate to the proximal veins, despite early diagnosis. 50% of calf clots totally lyse in 4 months, yet reflux develops in at least 75% of limbs with DVT. Further studies to determine optimal prophylaxis are warranted.

Post-viraemic detection of bovine ephemeral fever virus by use of autogenous lymphoid tissue-derived bovine primary cell cultures

BACKGROUND

The potential tissue replication sites and specific cell types that support in vivo virus survival beyond the acute phase of bovine ephemeral fever virus (BEFV) infection have not been fully defined in cattle. To clarify the knowledge gap, tissue specimens were tested after collection from an adult steer necropsied 1 week after acute BEF.

CASE REPORT

Significant necropsy findings included fibrinoproliferative synovitis in the stifle joints and fibrin clot-laden fluid in serous body cavities. Moderate numbers of infiltrating neutrophils were demonstrated in sections of the prefemoral lymph nodes and haemal node, and lymphoid hyperplasia in the spleen, haemal node and prefemoral lymph nodes. Viral RNA was detected by qRT-PCR in fresh spleen, haemal node, prefemoral lymph node, synovial fluid and in several spleen-derived cell cultures. BEFV was isolated from autogenously derived splenic primary cell cultures 6 days after cessation of viraemia, and characteristic bullet-shaped virions were confirmed by electron microscopy of an ultrathin haemal node section. In sections of the spleen, haemal node and other tissues, immunohistochemistry demonstrated BEFV antigens that were intracellularly associated with probable histiocytic cells.

CONCLUSION

BEFV has preferential tropism for bovine lymphoid tissues and the spleen and haemal node may be potential sites for post-viraemic virus replication.

Viral neurotropism, peripheral neuropathy and other morphological abnormalities in bovine ephemeral fever virus-infected downer cattle

OBJECTIVE

This study assessed the neurotropism of bovine ephemeral fever (BEF) virus (BEFV) and described histomorphological abnormalities of the brain, spinal cord and peripheral nerves that may causally contribute to paresis or paralysis in BEF.

METHODS

Four paralysed and six asymptomatic but virus-infected cattle were monitored, and blood and serum samples screened by qRT-PCR, virus isolation and neutralisation tests. Fresh brain, spinal cord, peripheral nerve and other tissues were qRT-PCR-tested for viral RNA, while formalin-fixed specimens were processed routinely and immunohistochemically evaluated for histomorphological abnormalities and viral antigen distribution, respectively.

RESULTS

The neurotropism of BEFV was immunohistochemically confirmed in the brain and peripheral nerves and peripheral neuropathy was demonstrated in three paralysed but not the six aneurological but virus-infected animals. Wallerian degeneration (WD) was present in the ventral funicular white matter of the lumbar spinal cord of a paralysed steer and in cervical and thoracic spinal cord segments of three paralysed animals. Although no spinal cord lesions were seen in the steer euthanased within 7 days of illness, peripheral neuropathy was present and more severe in nerves of the brachial plexuses than in the gluteal or fibular nerves. The only steer with WD in the lumbar spinal cord also showed intrahistiocytic cell viral antigen that was spatially distributed within areas of moderate brain stem encephalitis.

CONCLUSION

The data confirmed neurotropism of BEFV in cattle and documented histomorphological abnormalities in peripheral nerves and brain which, together with spinal cord lesions, may contribute to chronic paralysis in BEFV-infected downer cattle.

Evidence-based guidelines for treating bipolar disorder: Revised third edition recommendations from the British Association for Psychopharmacology

The British Association for Psychopharmacology guidelines specify the scope and targets of treatment for bipolar disorder. The third version is based explicitly on the available evidence and presented, like previous Clinical Practice Guidelines, as recommendations to aid clinical decision making for practitioners: it may also serve as a source of information for patients and carers, and assist audit. The recommendations are presented together with a more detailed review of the corresponding evidence. A consensus meeting, involving experts in bipolar disorder and its treatment, reviewed key areas and considered the strength of evidence and clinical implications. The guidelines were drawn up after extensive feedback from these participants. The best evidence from randomized controlled trials and, where available, observational studies employing quasi-experimental designs was used to evaluate treatment options. The strength of recommendations has been described using the GRADE approach. The guidelines cover the diagnosis of bipolar disorder, clinical management, and strategies for the use of medicines in short-term treatment of episodes, relapse prevention and stopping treatment. The use of medication is integrated with a coherent approach to psychoeducation and behaviour change.

The Norwich Patellar Instability Score: Validity, internal consistency and responsiveness for people conservatively-managed following first-time patellar dislocation

BACKGROUND

This paper assessed the validity, internal consistency, responsiveness and floor-ceiling effects of the Norwich Patellar Instability (NPI) Score for a cohort of conservatively managed people following first-time patellar dislocation (FTPD).

METHODS

Fifty patients were recruited, providing 130 completed datasets over 12 months. The NPI Score, Lysholm Knee Score, Tegner Level of Activity Score and isometric knee extension strength were assessed at baseline, six weeks, six and 12 months post-injury.

RESULTS

There was high convergent validity with a statistically significant correlation between the NPI Score and the Lysholm Knee Score (p<0.001), Tegner Level of Activity Score (p<0.001) and isometric knee extension strength (p<0.002). Principal component analysis revealed that the NPI Score demonstrated good concurrent validity with four components account for 70.4% of the variability. Whilst the NPI Score demonstrated a flooring-effect for 13 of the 19 items, no ceiling effect was reported. There was high internal consistency with a Cronbach Alpha value of 0.93 (95% CI: 0.91 to 0.93). The NPI Score was responsive to change over the 12 months period with an effect size of 1.04 from baseline to 12 months post-injury.

CONCLUSIONS

The NPI Score is a valid tool to assess patellar instability symptoms in people conservatively managed following FTPD.

LEVEL OF EVIDENCE

Level II.

Kinetics of selected plasma cytokines during innate-adaptive immune response transition in adult cattle infected with the bovine ephemeral fever virus

While virus neutralizing antibodies are known to be variably protective against bovine ephemeral fever (BEF) virus (BEFV) infections, the cytokine events that mediate the nascent adaptive immune response have not been defined in cattle. This study determined the plasma kinetics of IL-2, IFN-γ, IL-6, and IL-10 during the period of innate-immune response transition and evaluated the relationship between the virus neutralizing antibody response and viraemia in BEFV-infected cattle. Plasma from four virus-infected and uninfected negative control animals was tested by cytokine-specific immunoenzymatic assays, viraemia monitored by qRT-PCR, and virus neutralizing antibody titres determined using a standard protocol. Unlike the negative controls, plasma IL-6 and IL-10 were increased in all the virus-infected animals starting several days prior to initiation of viraemia. In one animal, plasma IL-2 and IFN-γ were consistently higher than in the other three virus-infected animals and the negative control mean. The animal with the strongest IL-2 and IFN-γ responses had the shortest viraemia while the heifer with the lowest IL-2/IFN-γ indices demonstrated the longest viraemia. Evidently, increase in plasma IL-6 and IL-10 precedes seroconversion during BEFV infections in cattle suggesting the two cytokines may influence immunological events that pave way to B-cell activation and seroconversion. While there is remarkable variability in IL-2 and IFN-γ expression amongst BEFV-infected animals, increased plasma levels of the two cytokines appear to be associated with a shorter viraemia. Ongoing studies will help define the precise role of T cells in anti-BEFV adaptive immune responses.

Died of wounds: a mortality review

OBJECTIVES

Combat casualty care is a complex system involving multiple clinicians, medical interventions and casualty transfers. Improving the performance of this system requires examination of potential weaknesses. This study reviewed the cause and timing of death of casualties deemed to have died from their injuries after arriving at a medical treatment facility during the recent conflicts in Iraq and Afghanistan, in order to identify potential areas for improving outcomes.

METHODS

This was a retrospective review of all casualties who reached medical treatment facilities alive, but subsequently died from injuries sustained during combat operations in Afghanistan and Iraq. It included all deaths from start to completion of combat operations. The UK military joint theatre trauma registry was used to identify cases, and further data were collected from clinical notes, postmortem records and coroner's reports.

RESULTS

There were 71 combat-related fatalities who survived to a medical treatment facility; 17 (24%) in Iraq and 54 (76%) in Afghanistan. Thirty eight (54%) died within the first 24 h. Thirty-three (47%) casualties died from isolated head injuries, a further 13 (18%) had unsurvivable head injuries but not in isolation. Haemorrhage following severe lower limb trauma, often in conjunction with abdominal and pelvic injuries, was the cause of a further 15 (21%) deaths.

CONCLUSIONS

Severe head injury was the most common cause of death. Irrespective of available medical treatment, none of this group had salvageable injuries. Future emphasis should be placed in preventative strategies to protect the head against battlefield trauma.

Kinetics of pro-inflammatory cytokines, interleukin-10, and virus neutralising antibodies during acute ephemeral fever virus infections in Brahman cattle

While fever and inflammation are hallmark features of bovine ephemeral fever (BEF), the cytokine networks that underlie the acute phase of the disease have not been empirically defined in cattle. This study characterised the plasma kinetics of proinflammatory cytokines (IL-1β, IL-6, TNF-α) and IL-10 during acute BEF and elucidated on the relationship between the onset of the virus neutralizing antibody response and resolution of viraemia in natural BEF virus (BEFV) infections in cattle. Plasma from three BEFV-infected and three uninfected cattle was tested for the study cytokines by a cELISA, viraemia monitored by qRT-PCR, and virus neutralizing antibody titres determined using a standard protocol. Unlike the negative controls, plasma concentrations of IL-1β, TNF-α, IL-6, and IL-10 were consistently increased in the three virus-infected animals. Two of the infected heifers were recumbent and pyrexic on the first day of monitoring and increased cytokine production was already in progress by the time viraemia was detected in all the three infected animals. In all the virus-infected heifers, IL-1β was the most strongly expressed cytokine, IL-6 and IL-10 manifested intermediate plasma concentrations while TNF-α was the least expressed and demonstrated bi-phasic peaks three and five days after the onset of pyrexia. In two of the BEFV-infected heifers, viraemia resolved on the day of seroconversion while in the other infected animal, viral RNA was detectable up to three days after seroconversion. The present data document variable increase in plasma IL-1β, IL-6, TNF-α, and IL-10 during natural BEFV infections and the fact that upregulation of all but TNF-α precedes seroconversion. In addition to virus neutralising antibodies, it is likely that cytokine-mediated cellular mechanisms may be required for resolution of viraemia in BEF. Considering the anti-inflammatory properties of IL-10, its upregulation may potentially antagonise the fever response in BEFV-infected cattle.

Isolated popliteus tendon injury does not lead to abnormal laxity in posterior-stabilised total knee arthroplasty

PURPOSE

The popliteus tendon is crucial to postero-lateral stability and prone to iatrogenic injury intra-operatively. Its role in the stability of the replaced knee remains contentious. The aim of this study was to use computer navigation to quantify the effect of popliteus sectioning on the 'envelope of laxity' (EoL) offered by a posterior-stabilised (PS) total knee arthroplasty (TKA) and compare with that of the native knee.

METHODS

Loaded cadaveric legs were mounted on a purpose built rig. EoL was measured in 3 degrees of freedom using computer navigation. Knees were subjectively stressed in varus/valgus, internal/external rotation and anterior draw. This was performed preoperatively, during TKA and after sectioning of the popliteus tendon. Real-time data were recorded at 0°, 30°, 60° and 90° of flexion as the operating surgeon stressed the knee in 3 degrees of freedom to its subjective endpoint. Mixed-effect modelling was used to quantify the effects of intervention on degree of laxity.

RESULTS

In all conditions, there was an increase in laxity with knee flexion. Insertion of a PS TKA resulted in increased constraint, particularly in rotation. Sectioning of the popliteus did not result in a significant increase in knee laxity to 90º of knee flexion. However, at deeper flexion angles, tendon sectioning overcame the constraints of the implant resulting in a significant increase in rotatory and varus/valgus laxity towards the native condition.

CONCLUSION

These findings support the view that certain current designs of PS knee replacement can constrain the knee in flexion in the absence of postero-lateral deficiency. For this implant, isolated sectioning of the popliteus tendon did not substantially generate abnormal knee laxity.

Experimental penetration of fragment simulating projectiles into porcine tissues compared with simulants

INTRODUCTION

Ballistic gelatin is well validated in its ability to simulate the retardation of bullets into homogenous muscle. However the relationship is less clear for fragmentation projectiles and non-homogenous tissues as would truly be found in a human.

METHOD

0.16 g, 1.10 g and 2.84 g NATO standardised cylindrical Fragment Simulating Projectiles (FSPs) were fired at a range of velocities (112-1652 m s(-1)) into four body areas (thigh, abdomen, thorax or neck) of six pig cadavers as well as 20% gelatin. Cadavers were imaged by Computed Tomography (CT) scanning and FSP Depth of Penetration (DoP) ascertained through radiology followed by dissection by a forensic pathologist.

RESULTS

106/149 (71%) FSPs were retained in tissues enabling DoP measurements and 43/149 (29%) exited the subjects. There was significantly less retardation of FSPs in the thorax and abdomen compared to gelatin but no difference in retardation in leg and neck tissue compared to gelatin. Although the gradient appeared identical for the 2.84 g FSP as well, there were insufficient FSPs retained in the neck and leg for meaningful analysis to be undertaken.

DISCUSSION

Porcine leg and neck muscle was demonstrated to be comparable to 20% ballistic gelatin in terms of retardation, validating the use of projectile penetration algorithms derived from this tissue simulant. The effect of pig skin was significant for the 0.16 g FSP, especially at lower velocities, and we would therefore suggest that specific algorithms for any future numerical injury models be based directly from animal data or validated skin simulants for this smaller sized FSP. Reproducing the retardation effects of FSPs in the thorax and abdomen using tissue simulants alone will be problematic due to the anatomical complexity as well as multiple tissue-air interfaces and we would recommend further research in this area.

Associated injuries in casualties with traumatic lower extremity amputations caused by improvised explosive devices

BACKGROUND

Improvised explosive devices (IEDs) pose a significant threat to military personnel, often resulting in lower extremity amputation and pelvic injury. Immediate management is haemorrhage control and debridement, which can involve lengthy surgery. Computed tomography is necessary to delineate the extent of the injury, but it is unclear whether to perform this during or after surgery.

METHODS

The UK Joint Theatre Trauma Registry was searched to identify all UK service personnel who had a traumatic lower extremity amputation following IED injury between January 2007 and December 2010. Data were collected on injury pattern and survival.

RESULTS

There were 169 patients who sustained 278 traumatic lower extremity amputations: 69 were killed in action, 16 died from their wounds and 84 were wounded in action, but survived. The median (interquartile range) Injury Severity Score was 75 (21) for those killed in action, 46 (23) for those who died from wounds and 29 (12) for survivors. There were significantly more severe head, chest and abdominal injuries (defined as a body region Abbreviated Injury Scale score of 3 or more) in patients who were killed in action than in those reaching hospital (P < 0·001). Hindquarter amputations were the most lethal, with a mortality rate of 95 per cent. Of the 100 casualties who reached hospital alive, there were nine thoracotomies, one craniotomy and 34 laparotomies. All head or torso injuries that required immediate operation were clinically apparent on admission.

CONCLUSION

Higher levels of amputation were associated with greater injury burden and mortality. Intraoperative computed tomography had little value in identifying clinically significant covert injuries.

Epitope mapping of the human TSH receptor; structure function studies

With the aid of recombinant DNA technology (PCR/site directed mutagenesis, sequencing) the full length coding region of the human TSH receptor was manipulated to place a specific epitope peptide tag (FLAG epitope sequence) at the carboxyl end of the protein. The resulting construct was cloned into a eukaryotic expression vector and stably transfected into HeLa cells. The expression/translation of the tagged TSH receptor molecule was monitored by immune-precipitation and western blotting of protein lysates, and was found to be expressed at considerable levels using the commercially available antibodies directed towards the FLAG epitope. This analysis revealed two discrete specific bands 90-120 KDa representing, presumably, differently glycosylated forms of the receptor. TSH radio receptor assays demonstrated that the FLAG tagged TSH receptor bound TSH comparable with the wild type receptor. Furthermore TSH stimulated cAMP response in these transfected cells were comparable to the wild type receptor, thus demonstrating that the tagged receptor was functionally identical to the transfected wild type receptor. These cell lines will be of great value when analysing TSH/receptor or receptor/autoantibody interactions considering the availability of well characterized experimental anti-TSH receptor sera.

Traumatic axonal damage in the brain can be detected using beta-APP immunohistochemistry within 35 min after head injury to human adults

Immunohistochemistry staining for beta-amyloid precursor protein (beta-APP) is a sensitive method to detect early axonal damage in traumatic brain injury, which was previously estimated to be of minimum 60-90 min after head injury. We present seven cases of well-documented posttraumatic survival of 35-60 min where beta-APP detects early axonal damage. Cases were selected from routine work where documentation about survival is judged to be accurate. These are divided into three groups: group 1: severe head injury (n = 7) with documented survival between 35 and 60 min. Group 2: severe head injury (n = 4) with documented survival of less than 30 min. Group 3: cases (n = 4) where death was not due to head injury but survival is documented between 45 and 109 min. The brains were fixed in formalin for 4 weeks and six regions (frontal lobe with anterior corpus callosum, parietal lobe with deep white matter, basal ganglia with posterior limb of internal capsule, cerebellum with white matter and middle cerebellar peduncle and pons with basis pontis and superior cerebellar peduncle) were sampled. All blocks were stained for haematoxylin and eosin and beta-APP and selected ones for CD68, using antigen retrieval method. In group 1 sections revealed beta-APP immunoreactivity in forms of small globules and granules and occasionally as thin and short filaments. These were detected in the pons, corpus callosum, internal capsule and cerebral white matter, with some variation in localization and intensity. In groups 2 and 3 all the sections were negative for beta-APP staining. None of the cases showed evidence of severe brain swelling, increased intracranial pressure, ischaemia or infection. Using the antigen retrieval method, beta-APP immunohistochemistry can detect axonal damage within 35 min after severe head injury. These results may have an implication in the consideration of minimal survival time after traumatic head injury in medico-legal practice.

Cultured skin fibroblast cells derived from bluetongue virus-inoculated sheep and field-infected cattle are not a source of late and protracted recoverable virus

A recent hypothesis to explain the recurrence of bluetongue disease after winter seasonal absences of the vector has suggested a role for persistent infection of sheep. This report presents combined independent work from two laboratories investigating the possible recovery of Bluetongue virus (BTV) over a protracted period after infection of both sheep and cattle. Prior to infection with either cell-culture-adapted or non-culture-adapted BTV, sheep were subjected to a preliminary exposure to Culicoides sp. insects, which reportedly facilitates recovery of virus from infected sheep several months post-infection (p.i.). A series of skin biopsies at different intervals p.i. was used to establish skin fibroblast (SF) cultures from which attempts were made to detect virus by isolation and by molecular and immunological methods. Also examined was the effect on virus recovery of additional exposure to Culicoides sp. prior to skin biopsy during the post-inoculation period. A herd of cattle sentinels for surveillance of natural BTV infection in northern Australia was monitored prospectively for seroconversion. Evidence of infection initiated attempted virus recovery by establishing SF cultures. It was found that in both cattle and sheep there was not a protracted period over which BTV could be recovered from SF cultures. The data do not support a general hypothesis that BTV persists in either sheep or cattle.

Falklands War veterans' perceptions of social support and the reconciliation of traumatic memories

The current paper focused on the role social support plays in the reconciliation of traumatic memories. Four currently serving, male Royal Marines ranging from 40-42 years participated in semi-structured one-to-one interviews that explored perceptions of social support. Using thematic analysis, comradeship was found to be important in terms of maintaining support networks. However, this resource was used to avoid the reconciliation of traumatic memories. Social support from family members was sought when veterans were reassured that relatives would understand their experiences, and could support reconciliation. The importance of positive societal reaction was also emphasized. The paper concludes by highlighting the potential for early life reconciliation of traumatic war memories through the creation of a meaningful personal narrative.

Calorie restriction induces mitochondrial biogenesis and bioenergetic efficiency

Age-related accumulation of cellular damage and death has been linked to oxidative stress. Calorie restriction (CR) is the most robust, nongenetic intervention that increases lifespan and reduces the rate of aging in a variety of species. Mechanisms responsible for the antiaging effects of CR remain uncertain, but reduction of oxidative stress within mitochondria remains a major focus of research. CR is hypothesized to decrease mitochondrial electron flow and proton leaks to attenuate damage caused by reactive oxygen species. We have focused our research on a related, but different, antiaging mechanism of CR. Specifically, using both in vivo and in vitro analyses, we report that CR reduces oxidative stress at the same time that it stimulates the proliferation of mitochondria through a peroxisome proliferation-activated receptor coactivator 1 alpha signaling pathway. Moreover, mitochondria under CR conditions show less oxygen consumption, reduce membrane potential, and generate less reactive oxygen species than controls, but remarkably they are able to maintain their critical ATP production. In effect, CR can induce a peroxisome proliferation-activated receptor coactivator 1 alpha-dependent increase in mitochondria capable of efficient and balanced bioenergetics to reduce oxidative stress and attenuate age-dependent endogenous oxidative damage.

Current management of bipolar affective disorder: is it reflective of the BAP guidelines?

In October 2003 the British Association of Psychopharmacology (BAP) published evidence-based guidelines on the management of bipolar disorder. The aim of this study was to assess whether the guidelines could provide the basis for examining clinical decisions and the extent to which practice accords with these guidelines. Case notes of out patients with bipolar disorder were reviewed. Demographic details, and treatment recommendations were determined. The management of affective episodes was evaluated and compared with BAP guidelines. In 84 subjects, 224 affective episodes were identified. Treatment was consistent with BAP guidelines in 72% of episodes. Mania was more likely to be managed in accordance with guidelines than depression or mixed episodes. The use of antidepressant medication was the most likely intervention to deviate from recommendations. Reasons for treatments at odds with the guidelines were identified. Our study demonstrates that clinical practice among a range of psychiatrists broadly reflects the guidelines that have been issued by the British Association of Psychopharmacology (BAP). The BAP guidelines offer a practical and auditable basis for the short- and long-term treatment of bipolar affective disorder.

Nitrogen and phosphorus removal from plant nursery runoff in vegetated and unvegetated subsurface flow wetlands

Subsurface horizontal flow reed beds are being evaluated for Nitrogen (N) and Phosphorus (P) removal from plant nursery runoff water in New South Wales Australia. The need to include plants (Phragmites australis), the effect of reaction time (3.5 v 7.0 d) and dissolved organic carbon (DOC) on N and P removal in batch fed gravel wetland tubs (55 L) was studied over 19 months. Simulated nursery runoff water containing N (10.1 mg L(-1), 74% as NO3) and P (0.58 mg L(-1), 88% as PO4) and DOC (2-5 mg L(-1)) was used. The planted wetland tubs removed >96% TN and TP over most of the 19-month study period while unplanted tubs were inefficient (<16% N and <45% P removal) and occasionally discharged nutrients. Doubling the reaction time to 7.0 days had no effect on nutrient removal. Plant nutrient uptake accounted for most of the N (76%) and P (86%) removed while roots and rhizomes were the dominant sink (N 58%, P 67%). The addition of methanol (C:N-3:1) to unplanted tubs achieved 81-98% N removal. In Carbon limited low nutrient nursery runoff, plants were essential to a gravel-based wetland to achieve efficient nutrient removal with effluent TN and TP concentrations of <1 mg L(-1) and 0.05 mg L(-1), respectively with a 3.5 day reaction time.

Genetic basis of erythromycin resistance in oral bacteria

We determined the prevalence of erythromycin-resistant bacteria in the oral cavity and identified mef and erm(B) as the most common resistance determinants. In addition, we demonstrate the genetic linkage, on various Tn1545-like conjugative transposons, between erythromycin and tetracycline resistance in a number of isolates.

Fibre mapping – a case study

Fibre mapping, more commonly known as one-to-one taping, was developed in Germany approximately twenty years ago. The technique facilitates the distribution of fibres on a surface to be recorded. The impact of this technique on the investigation of serious crime has been reported in the European Fibre Group on several occasions. This paper represents a case study of the application of the technique. It is believed to be the first time that this technique has been successfully applied in the United Kingdom.

An easy and accurate preoperative method for determining tibial nail lengths

Estimating the correct nail length for solid tibial nails can be problematic. Most techniques reported in the literature for determining tibial nail length are not accurate. In a retrospective study of 16 patients in our unit, only three had ideal nail sizes. In these patients, as part of phase I of our study, we measured their normal leg's length from knee joint line to ankle joint line. An ideal nail length for each of these patients was estimated from a whole length radiograph of the nailed tibia. Comparing these two data, we found that deducting 20 mm from the leg measurement gave appropriate nail lengths. We also compared this with three other anthropometric measurements; tibial tuberosity to medial malleolus, joint line to medial malleolus and olecranon to head of V metacarpal head distance. The joint line to joint line measurement was the most reliable and showed the best correlation with ideal nail lengths (0.982). In phase II, a prospective study on 15 patients, we used the joint line to joint line measurement to determine nail sizes. A postoperative review of the radiographs showed all the nails to be of adequate length. This strengthened the fact that the joint line to joint line measurement is the most accurate and easy method to determine tibial nail lengths.

Novel tetracycline resistance determinant from the oral metagenome

A major drawback of most studies on how bacteria become resistant to antibiotics is that they concentrate mainly on bacteria that can be cultivated in the laboratory. In the present study, we cloned part of the oral metagenome and isolated a novel tetracycline resistance gene, tet(37), which inactivates tetracycline.