Ileorectal anastomosis in ulcerative colitis: what do surgeons and patients need to know? A systematic literature review

INTRODUCTION

Ileal pouch-anal anastomosis (IPAA) is currently the gold standard for restoration of gastrointestinal continuity after colectomy for ulcerative colitis in the UK. However, with further experience of the risks relating to IPAA, the use of ileorectal anastomosis (IRA) is being revisited. Decisions regarding restorative surgery after colectomy are individual to every patient's circumstances, and this paper aims to provide a comprehensive review of the literature to guide a full discussion of the risks and benefits of IRA.

METHODS

A systematic literature review was conducted of papers published from 2000 onwards relating to IRA and ulcerative colitis, in accordance with the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. The papers were reviewed by two independent surgeons for information it was felt that patients and surgeons would want to know about the operation (cancer risk, bowel function, sexual and urinary function, fecundity/fertility and postoperative complications).

RESULTS

Seventeen papers were identified for inclusion as they reported original data on one or more of the categories identified for discussion. The median ten-year cancer risk after IRA was 2.8% and the median failure rate at ten years was 21%. IRA was generally found to have lower postoperative complication rates and better bowel function than IRA, with sexual function similar and fecundity not commented on in any paper.

CONCLUSIONS

For some patients, IRA can offer restorative surgery in the short or long term, with acceptable cancer risk, failure rate and postoperative complications, while avoiding the higher risks associated with IPAA.

Determination of tilt angle and its behavior in chiral smectic phases by exploring molecular conformations using complementary methods

Density functional theory (DFT) calculations and x-ray diffraction techniques were employed to evaluate the value of the tilt angle in ferroelectric smectic C^{*} and antiferroelectric smectic C_{A}^{*} phases. Five homologues from the chiral series denoted as 3FmHPhF6(m=2,4,5,6,7), based on 4-(1-methylheptyloxycarbonyl) phenyl 4'-octyloxybiphenyl-4-carboxylate (MHPOBC), were studied. Two types of conformations for the nonchiral terminal chain (fully extended and gauche) and three types of deviation from the rodlike shape of the molecules (hockey stick, zigzag, and C shape) were computationally considered. The nonlinear shape of the molecules was accounted for by introducing a shape parameter δΘ. We observe that calculations of the tilt angle which consider the C-shaped structures, in both the fully extended or gauche conformations, lead to good agreement with the values of the tilt angle obtained from electro-optical measurements below the saturation temperature. The results allow us to conclude that such structures are adopted by molecules in the examined series of smectogens. Additionally, this study proves the presence of the standard orthogonal SmA^{*} phase for the homologues with m=6, 7, and the de Vries SmA^{*} phase for m=5.

Anaesthesia for vascular emergencies - a state of the art review

In this state-of-the-art review, we discuss the presenting symptoms and management strategies for vascular emergencies. Although vascular emergencies are best treated at a vascular surgical centre, patients may present to any emergency department and may require both immediate management and safe transport to a vascular centre. We describe the surgical and anaesthetic considerations for management of aortic dissection, aortic rupture, carotid endarterectomy, acute limb ischaemia and mesenteric ischaemia. Important issues to consider in aortic dissection are extent of the dissection and surgical need for bypasses in addition to endovascular repair. From an anaesthetist's perspective, aortic dissection requires infrastructure for massive transfusion, smooth management should an endovascular procedure require conversion to an open procedure, haemodynamic manipulation during stent deployment and prevention of spinal cord ischaemia. Principles in management of aortic rupture, whether open or endovascular treatment is chosen, include immediate transfer to a vascular care centre; minimising haemodynamic changes to reduce aortic shear stress; permissive hypotension in the pre-operative period; and initiation of massive transfusion protocol. Carotid endarterectomy for carotid stenosis is managed with general or regional techniques, and anaesthetists must be prepared to manage haemodynamic, neurological and airway issues peri-operatively. Acute limb ischaemia is a result of embolism, thrombosis, dissection or trauma, and may be treated with open repair or embolectomy, under either general or local anaesthesia. Due to hypercoagulability, there may be higher numbers of acutely ischaemic limbs among patients with COVID-19, which is important to consider in the current pandemic. Mesenteric ischaemia is a rare vascular emergency, but it is challenging to diagnose and associated with high morbidity and mortality. Several peri-operative issues are common to all vascular emergencies: acute renal injury; management of transfusion; need for heparinisation and reversal; and challenging postoperative care. Finally, the important development of endovascular techniques for repair in many vascular emergencies has improved care, and the availability of transoesophageal echocardiography has improved monitoring as well as aids in surgical placement of endovascular grafts and for post-procedural evaluation.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Feasibility of single-use 3D-printed instruments for total knee arthroplasty

Aims

This aim of this study was to assess the feasibility of designing and introducing generic 3D-printed instrumentation for routine use in total knee arthroplasty.

Materials and Methods

Instruments were designed to take advantage of 3D-printing technology, particularly ensuring that all parts were pre-assembled, to theoretically reduce the time and skill required during surgery. Concerning functionality, ranges of resection angle and distance were restricted within a safe zone, while accommodating either mechanical or anatomical alignment goals. To identify the most suitable biocompatible materials, typical instrument shapes and mating parts, such as dovetails and screws, were designed and produced.

Results

Before and after steam sterilization, dimensional analysis showed that acrylonitrile butadiene styrene could not withstand the temperatures without dimensional changes. Oscillating saw tests with slotted cutting blocks produced debris, fractures, or further dimensional changes in the shape of Nylon-12 and polymethylmethacrylate (MED610), but polyetherimide ULTEM 1010 was least affected.

Conclusion

The study showed that 3D-printed instrumentation was technically feasible and had some advantages. However, other factors, such as whether all procedural steps can be accomplished with a set of 3D-printed instruments, the logistics of delivery, and the economic aspects, require further study. Cite this article: Bone Joint J 2019;101-B(7 Supple C):115–120

Patients' understanding of cellulitis and views about how best to prevent recurrent episodes: mixed-methods study in primary and secondary care

BACKGROUND

Cellulitis is a common painful infection of the skin and underlying tissues that recurs in approximately one-third of cases. The only proven strategy to reduce the risk of recurrence is long-term, low-dose antibiotics. Given current concerns about antibiotic resistance and the pressure to reduce antibiotic prescribing, other prevention strategies are needed.

OBJECTIVES

To explore patients' views about cellulitis and different ways of preventing recurrent episodes.

METHODS

Adults aged ≥ 18 years with a history of first-episode or recurrent cellulitis were invited through primary care, hospitals and advertising to complete a survey, take part in an interview or both.

RESULTS

Thirty interviews were conducted between August 2016 and July 2017. Two hundred and forty surveys were completed (response rate 17%). Triangulation of quantitative and qualitative data showed that people who have had cellulitis have wide-ranging beliefs about what can cause cellulitis and are often unaware of risk of recurrence or potential strategies to prevent recurrence. Enhanced foot hygiene, applying emollients daily, exercise and losing weight were more popular potential strategies than the use of compression stockings or long-term antibiotics. Participants expressed caution about long-term oral antibiotics, particularly those who had experienced only one episode of cellulitis.

CONCLUSIONS

People who have had cellulitis are keen to know about possible ways to prevent further episodes. Enhanced foot hygiene, applying emollients daily, exercise and losing weight were generally viewed to be more acceptable, feasible strategies than compression or antibiotics, but further research is needed to explore uptake and effectiveness in practice.

A systematic review of McKittrick-Wheelock syndrome

INTRODUCTION

McKittrick-Wheelock syndrome describes the condition of extreme electrolyte and fluid depletion caused by large distal colorectal tumours, usually the benign villous adenoma. Patients generally present critically unwell with severe hyponatraemia, hypokalaemia and/or acute kidney injury.

METHODS

A structured literature review was undertaken to discover what is known about this condition, which is almost universally described as rare. Important features of the syndrome were identified, including common presenting symptoms, blood results, tumour location and size.

FINDINGS

Our literature search identified 257 cases reported across all languages. The most remarkable features were the long duration of symptoms (median 24 months) and the significant electrolyte derangements (median sodium of 122mmol/l and median potassium of 2.7mmol/l at initial presentation). Five key recommendations are made to improve diagnosis, including aggressive fluid resuscitation to match rectal losses and surgical intervention on the index admission. The advantages and disadvantages of different treatment options are discussed, including minimally invasive alternatives to traditional resectional surgery.

CONCLUSIONS

McKittrick-Wheelock syndrome describes a normally benign condition that can cause patients to become critically unwell and so it behoves all clinicians to be aware of it. By publishing recommendations based on a comprehensive literature review, we aim to improve diagnosis and management of this life threatening condition.

A Reference Range for Plasma Total Calcium Derived from a Study of Hospital Patients

The normal ranges of plasma total calcium in male and female inpatients and outpatients in a district general hospital have been determined using the SMA PLUS (Technicon Instrument Company Ltd., Basingstoke, England), after selective sampling to exclude cases likely to have abnormal results both on clinical and on biochemical grounds. The 95% ranges were 2.15–2.60 mmol/l for inpatients and 2.25–2.65 mmol/l for outpatients.

Early diagnosis of cardiac implantable electronic device generator pocket infection using ¹⁸F-FDG-PET/CT

AIMS

To examine the utility of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in the early diagnosis of cardiac implantable electronic device (CIED) generator pocket infection.

METHODS AND RESULTS

A total of 86 patients with CIEDs were evaluated with (18)F-FDG PET/CT imaging: 46 with suspected generator pocket infection and 40 without any history of infection. (18)F-FDG activity in the region of the generator pocket was expressed as a semi-quantitative ratio (SQR)-defined as the maximum count rate around the CIED divided by the mean count rate between normal right and left lung parenchyma. All patients underwent standard clinical management, independent of the PET/CT result. Patients with suspected generator pocket infection that required CIED extraction (n = 32) had significantly higher (18)F-FDG activity compared with those that did not (n = 14), and compared with controls (n = 40) [SQR: 4.80 (3.18-7.05) vs. 1.40 (0.88-1.73) vs. 1.10 (0.98-1.40), respectively; P < 0.001]. On receiver operator characteristic analysis, SQR had a high diagnostic accuracy (area under curve = 0.98) for the early identification of patients with confirmed infection (i.e. those ultimately needing extraction)-with an optimal SQR cut-off value of >2.0 (sensitivity = 97%; specificity = 98%).

CONCLUSION

This study highlights the potential benefits of evaluating patients with suspected CIED generator pocket infection using (18)F-FDG PET/CT. In this study, (18)F-FDG PET/CT had a high diagnostic accuracy in the early diagnosis of CIED generator pocket infection, even where initial clinical signs were underwhelming.

Integrated care pathways for airway diseases (AIRWAYS-ICPs)

The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will add value to existing public health knowledge by: 1) proposing a common framework of care pathways for chronic respiratory diseases, which will facilitate comparability and trans-national initiatives; 2) informing cost-effective policy development, strengthening in particular those on smoking and environmental exposure; 3) aiding risk stratification in chronic disease patients, using a common strategy; 4) having a significant impact on the health of citizens in the short term (reduction of morbidity, improvement of education in children and of work in adults) and in the long-term (healthy ageing); 5) proposing a common simulation tool to assist physicians; and 6) ultimately reducing the healthcare burden (emergency visits, avoidable hospitalisations, disability and costs) while improving quality of life. In the longer term, the incidence of disease may be reduced by innovative prevention strategies. AIRWAYSICPs was initiated by Area 5 of the Action Plan B3 of the European Innovation Partnership on Active and Healthy Ageing. All stakeholders are involved (health and social care, patients, and policy makers).

Serological and molecular evidence of a plausible transmission of hepatitis E virus through pooled plasma

BACKGROUND AND OBJECTIVES

Recently, hepatitis E virus has been recognized as a new transfusion-associated risk; however, its efficiency of transmission through blood products requires further investigation. Asymptomatic viremia of short duration has been observed in blood donors from several European countries to the rate of <1:10,000 and HEV transmission in recipients of blood products has been documented in Japan and Europe. Although HEV RNA was detected in large plasma fractionation pools used for manufacturing of plasma derived products, HEV transmission has not been demonstrated so far. In this study, we investigated the possibility of HEV transmission in patients with thrombotic thrombocytopenic purpura whose treatment included up to 40 l of plasma exchange.

MATERIALS AND METHODS

Thirty-six TTP patients received either solvent-detergent-treated plasma prepared by pooling of 2500 single-donor or cryosupernatant plasma. Three samples were collected from TTP patients at time 0, 1 and 6 months post-treatment and tested for anti-HEV antibodies. Patients with HEV seroconversion were also tested for viremia by PCR.

RESULTS

Two of seventeen TTP patients treated with SDP showed serological evidence of HEV infection. The 1-month samples from these patients were also positive for HEV RNA. A distinct rise of anti-HEV IgG level was detected in two other TTP patients with weak pre-existing immunity to HEV; this observation is indicative of a possible immune response boost due to a breakthrough infection.

CONCLUSION

This work provides, for the first time, indirect evidence of HEV transmission by pooled plasma and warrants further studies.

Kagome-like lattice of π–π stacked 3-hydroxyphenalenone on Cu(111)

Three-dimensional arrangement of 3-HPLN on a 2D surface, involving π–π stacking and perpendicular molecule attachment, results in a Kagome lattice.

009. KALLIKREIN-RELATED PROTEASES AS NOVEL THERAPEUTIC TARGETS IN PROSTATE AND OVARIAN CANCER

The kallikrein-related (KLKs) peptidases are implicated in prostate and ovarian cancer invasion/metastasis via activation of growth factors, proteases and extracellular matrix degradation involved in. In our published work, we used cell biology approaches to show novel associations of KLK peptidases with processes indicative of metastasis and the potential of our novel sunflower trypsin inhibitor scaffold-engineered KLK4 inhibitor. Our current studies are directed towards discovering the precise KLK target proteins/substrates and the subsequent signalling pathways involved in these events in order to determine their therapeutic target potential. In this regard, we are using novel tissue engineered biomimetic 3D gel matrices to better mimic the in vivo micro-environment of prostate cancer cells especially in bone metastasis and peritoneal invasion in ovarian cancer. Pilot studies show that PC3 cells cultured on an osteoblast-derived bone matrix undergo an EMT-like change but remain dispersed on the cell surface. In contrast, LNCaP cells cluster aligning with the fibrillar structure as they invade into the bone matrix as typically seen in vivo. KLK4 proteolysis of the osteoblast-derived bone matrix has identified additional novel substrates. In addition, we are exploring the cell biology that underlies the reported high KLK4 or KLK7 levels associated with poorer outcome in women with epithelial ovarian cancer (EOC). Of note, KLK4 or KLK7 transfected SKOV3 EOC cells have increased chemoresistance to taxol and/or cisplastin suggesting a mechanism for this poor outcome. Furthermore, KLK7 transfected SKOV-3 cells form multicellular aggregates (MCA) in agarose suspension (a process indicative of peritoneal tumour cell spread seen in ascites fluid clinically) which can be reversed by a KLK7 blocking antibody indicating the critical role played by KLK7 in this event. These new paradigms are providing novel information on the role of KLK peptidases in prostate and ovarian cancer progression and their potential as novel therapeutic targets.

Characterization of porcine beta1- and beta2-adrenergic receptors in heart, skeletal muscle, and adipose tissue, and the identification of an atypical beta-adrenergic binding site

The objective of this study was to characterize porcine beta1- and beta2-adrenergic receptors (beta1-AR and beta2-AR) in heart, skeletal muscle, and adipose tissue by measuring the binding of a radioligand to cell membrane fragments. In skeletal muscle (LM), [3H]CGP12177 labeled a homogeneous population of beta2-AR as evidenced by the rank order of affinity of catecholamines [(-)isoproterenol > (-)epinephrine > (-)norepinephrine], a high affinity of the binding site for the beta2-AR-agonist clenbuterol (equilibrium dissociation constant, Kd = 16 nM), and a low affinity of the binding site for the beta1-AR-antagonist CGP20712A (Kd = 21 microM). The affinity of ICI118551, a ligand selective for beta2-AR in other species, was uncharacteristically low in porcine LM (Kd = 441 nM), but was consistent with a value reported for the cloned porcine beta2-AR. In heart ventricle, ligand binding revealed a predominant population of beta1-AR, judged by the rank order of affinity of catecholamines [(-)isoproterenol > (-)epinephrine > or = (-)norepinephrine] and high-affinity binding to CGP20712A (Kd = 40 nM). The Kd for ICI118551 (731 nM) was close to that observed at beta2-AR in LM, confirming that ICI118551 is not subtype-selective in the pig. Displacement studies using (-)propranolol, clenbuterol, and (-)isoproterenol revealed a second high-affinity binding site in the heart that was not a beta2-AR and could not be eliminated by guanosine 5'-triphosphate or guanylyli-midodiphosphate. In adipose tissue, an equal number of beta1- and beta2-AR was identified through the binding of clenbuterol and CGP20712A, whereas ICI118551 could not discriminate between these sites. In further experiments, we used 10 microM CGP20712A to eliminate beta1-AR binding and allow accurate Kd values to be determined at beta2-AR for nonselective ligands. Under these conditions, another binding site was observed that had a high affinity for (-)propranolol (Kd = 20 pM), which is inconsistent with beta3- or beta4-AR binding reported elsewhere. Our results indicate that porcine adipose tissue contains beta1-AR, beta2-AR, and an atypical binding site in the proportions 50, 34, and 16%, respectively, of the total binding sites labeled by [3H]CGP12177.

Relationship of vascular risk to the progression of Alzheimer disease

OBJECTIVE

To test the hypothesis that patients with Alzheimer disease (AD) who have vascular risk factors have a worse prognosis over 18 months vs those without such risk factors.

METHODS

A sample of 224 people with AD and their caregivers were recruited purposively to be representative of people with dementia in terms of cognition, sex, and living situations in a longitudinal study of AD. Standardized instruments measuring cognition, functional status, and neuropsychiatric symptoms were used to collect data. Physical examination and relevant blood tests were performed.

RESULT

There was no difference in rate of deterioration between people with and without vascular risk factors, except in those who had a cerebrovascular accident (CVA) during the 18-month follow-up (p < 0.001). We considered possible confounders of outcome: sex, age, years of education, severity of dementia, depression, taking cholinesterase inhibitors (AChEIs), and whether those with vascular risk factors were more likely to die, but the results remained unchanged. Stopping AChEIs during the study was associated with cognitive and functional decline (p < 0.001).

CONCLUSIONS

Vascular risk factors as measured clinically and biochemically do not significantly increase deterioration at 18 months in people with Alzheimer disease who have a low burden of cerebrovascular risk factors. However, cerebrovascular events are associated with more rapid decline. Vascular risk factors may contribute to the expression of Alzheimer disease initially but are not part of the underlying etiologic process.

Systematic method to new phases of polymeric nitrogen under high pressure

A systematic method to unravel a large class of single-bonded (SB) polymeric phases of nitrogen under high pressure is presented. The approach is based on the combinatorial generation of different Peierls-like distortions of a given reference structure that maintain the threefold connectivity of SB nitrogen, followed by first-principles calculations. Using an eight atom simple cubic reference structure, the approach not only recovers all four SB nitrogen phases reported to date, but eight new metastable structures (confirmed by phonon density of states calculations) are found. Basic properties of the structures are computed and the trends analyzed. Extensions to the method are straightforward and should lead to the discovery of more phases of polynitrogen.

Adherence to antiretroviral therapy and its impact on clinical outcome in HIV-infected patients

We analyse data on patient adherence to prescribed regimens and surrogate markers of clinical outcome for 168 human immunodeficiency virus infected patients treated with antiretroviral therapy. Data on patient adherence consisted of dose-timing measurements collected for an average of 12 months per patient via electronic monitoring of bottle opening events. We first discuss how such data can be presented to highlight suboptimal adherence patterns and between-patient differences, before introducing two novel methods by which such data can be statistically modelled. Correlations between adherence and subsequent measures of viral load and CD4+T-cell counts are then evaluated. We show that summary measures of short-term adherence, which incorporate pharmacokinetic and pharmacodynamic data on the monitored regimen, predict suboptimal trends in viral load and CD4+T-cell counts better than measures based on adherence data alone.

Allelic imbalance and biochemical outcome after radical prostatectomy

OBJECTIVE

To compare the incidence of allelic imbalance (AI) in men with rapid disease progression with those who remained disease free after radical prostatectomy, with the aim of identifying genetic markers to predict prognosis and guide further treatment.

PATIENTS AND METHODS

Tumour and normal DNA were extracted from two matched groups of 31 men with extracapsular node-negative (pT3N0) prostate cancer who had undergone radical prostatectomy. One group comprised men who developed biochemical recurrence within 2 years of surgery and one group were prostate-specific antigen (PSA) free for at least 3 years. Men were matched for Gleason grade, preoperative PSA and pathological stage. Analysis was performed by genotyping.

RESULTS

Allelic imbalance was analysed using 30 markers, and was seen in at least one marker in 57 (92%) of the cases. Deletion at marker D10S211 (10p12.1) was significantly more common in the relapse group than the non-relapse group (35 vs 5%, P=0.03).

CONCLUSIONS

This study demonstrates significant association between AI on chromosome 10 and biochemical progression after radical prostatectomy.

Phase separation in the itinerant metamagnetic transition of Sr4Ru3O10

We have investigated the electronic transport properties of the triple-layered ruthenate Sr4Ru3O10. We observed surprising anomalous features near its itinerant metamagnetic transition, including ultrasharp magnetoresistivity steps, a nonmetallic temperature dependence in resistivity for upward field sweeps, and a resistivity drop in temperature dependence for downward field sweeps. These features suggest that the metamagnetic transition of Sr4Ru3O10 occurs via an electronic phase separation process with magnetic domain formation.

Automated quantitation of peripheral blood neutrophil activation in patients with myocardial ischaemia

BACKGROUND

Coronary ischaemic syndromes are associated with neutrophil activation. The Bayer automated haematology analysers can detect increased light scatter of neutrophil populations, which correlates with neutrophil activation. We aimed to assess the role of an automated analyser in detecting systemic neutrophil activation in peripheral blood samples of patients with coronary ischaemia.

METHODS

A prospective cross-sectional study was undertaken in 18 patients with chronic stable angina, 9 with unstable angina and 26 normal control subjects. Whole blood samples were taken to assess neutrophil count and light scatter, and serum samples were taken from some patients for assessment of Troponin T, C-reactive protein (CRP) and myeloperoxidase (MPO). In addition, whole blood was stimulated in vitro with interleukin (IL)-8 and N-formyl-methionyl-leucyl-phenylalanine (fMLP) to assess changes in neutrophil light scatter detected by the analyser.

RESULTS

Neutrophil light scatter was increased in patients with chronic stable and unstable angina compared to normal control subjects (normal subjects 74.1 (73.3, 75.0) (mean arbitrary units (95% confidence intervals, (CI)) vs. 78.6 (76.9, 80.3) in the chronic stable angina group P<0.001 and 77.1 (75.3, 79.0) in the unstable angina group P<0.007). In vitro stimulation of whole blood produced comparable increases in neutrophil light scatter when morphological changes in neutrophils were demonstrable under electron microscopy.

CONCLUSIONS

Automated measurement of neutrophil activation by light scatter is possible using the Advia 120 analyser and is superior to a neutrophil count in discriminating groups with angina. This technique may be useful in monitoring disease activity and progression in coronary artery disease and in guiding the use of anti-inflammatory therapies.

Costs of thalamic deep brain stimulation for movement disorders in patients with multiple sclerosis

Several studies have shown that thalamic deep brain stimulation (DBS) reduces tremor and improves hand performance in patients with multiple sclerosis (MS). The purpose of this paper is to describe the cost implications of DBS in MS patients and to highlight postoperative medical requirements that can be associated with this therapy. In a prospective study of thalamic DBS in MS patients the mean equipment costs were pounds 4769 (median pounds 7010, Medtronic, 1998 prices); mean neurosurgical inpatient costs per operated patient (n = 15) were pounds 4848 (range pounds 1982-8920, median pounds 5110); and mean in-patient postoperative rehabilitation cost pounds 4602 (range pounds 0-32,225, median pounds 1783). In addition there were transport and follow up costs. Mean neurosurgical inpatient stay following stereotactic DBS implantation was 15 days (median 12 days); and mean inpatient, postoperative rehabilitation stay 54 days (median 25 days). Although there were significant improvements in hand function and tremor reduction at 12 months postoperation, the level of patient performance in activities of daily living, their perception of their handicap and ipse facto the amount of home support required were unchanged from preoperative levels. This study has highlighted significant unforeseen medical requirements and costs that can occur in MS patients who have thalamic DBS surgery.

Cumulative risk assessment in unstable angina: clinical, electrocardiographic, autonomic, and biochemical markers

OBJECTIVES

To determine the incremental value of clinical data, troponin T, ST segment monitoring, and heart rate variability for predicting outcome in patients with non-ST elevation acute coronary syndromes.

METHODS

Prospective cohort study of 304 consecutive patients. Baseline clinical and electrocardiographic data were recorded, serial blood samples were obtained for troponin T assay, and 48 hour Holter monitoring was performed for ST segment and heart rate variability analysis. End points were cardiac death and non-fatal myocardial infarction during 12 months' follow up.

RESULTS

After 12 months, 7 patients had died and 21 had had non-fatal myocardial infarction. The risk of an event was increased by troponin T > 0.1 microg/l, T wave inversion on the presenting ECG, Holter ST shift, and a decrease in the standard deviation of 5 minute mean RR intervals. Positive predictive values of individual multivariate risk were low; however, analysis of all multivariate risk markers permitted calculation of a cumulative risk score, which increased the positive predictive value to 46.9% while retaining a negative predictive value of 96.9%.

CONCLUSION

A cumulative approach to risk stratification in non-ST elevation coronary syndromes successfully identifies a group in whom the risk of cardiac death or non-fatal myocardial infarction approaches 50%.

A prospective study of thalamic deep brain stimulation for the treatment of movement disorders in multiple sclerosis

The place for neurosurgical management of movement disorders in multiple sclerosis is unclear. To evaluate the potential benefits of unilateral thalamic deep brain stimulation (DBS) a prospective study was performed. Fifteen patients with confirmed MS and chronic, severe, drug-resistant movement disorders underwent stereotactic surgery to implant a thalamic DBS electrode using CT image guidance and intra-operative neurophysiological testing. The primary outcome measures were reduction in tremor severity and improvement in tests of hand function when the DBS electrode was turned on, 12 months after surgery. Secondary outcome measures included indices of disability, handicap, neuropsychological function and independence. Thirty-seven patients were assessed for treatment, but only 15 underwent surgery. In the 10 patients in whom implantation of the complete DBS system was carried out there was a significant reduction in the severity of tremor (p = 0.02) and improvement in hand function (p = 0.02). There were no benefits in any of the secondary outcome measures. Two patients had thalamocapsular haemorrhages at the site of electrode implantation and two had seizures in the follow-up period. Thalamic stimulation significantly reduced the tremor associated with MS and improved hand function in the targeted upper limb. However, there can be difficulties with identifying an optimal implantation site during operation, significant procedural morbidity and difficulty in predicting immediate outcome. It is also likely that the insignificant benefits of DBS on disability and handicap reflect persisting cerebeller dysmetria, and both the severity and diffuse nature of the disease process in this patient cohort.

Cystic fibrosis-related diabetes: the role of peripheral insulin resistance and beta-cell dysfunction

AIMS

The goal of this study was to identify the glycaemic status and investigate the roles of peripheral insulin resistance (IR) and pancreatic -cell dysfunction in the pathogenesis of cystic fibrosis-related diabetes (CFRD) in adult cystic fibrosis (CF) patients with no previous history of glycaemic disturbances.

METHODS

The glucose tolerance status of 68 CF patients was determined using 2-h oral glucose tolerance tests (OGTTs). Peripheral IR was measured using the homeostasis model assessment for insulin resistance (HOMA-IR) in the CF group and 46 normal healthy control subjects. Pancreatic -cell function, calculated as the ratio between the 30-min increment in plasma insulin and the corresponding 30-min post-OGTT plasma glucose concentration, was also measured in a subset of 30 CF patients and 16 normal healthy controls. Extended 180-min OGTTs, with frequent plasma glucose and insulin sampling, were also undertaken in 24 CF patients and eight normal healthy controls to determine glucose-induced insulin response.

RESULTS

Of the 68 CF patients studied, 41, 18 and nine were found to have normal, impaired and diabetic glucose tolerances, respectively. The mean HOMA-IR values (mU/mmol) in the CF patients, as a whole, were not significantly different compared with the normal healthy controls (CF 2.2 +/- 1.1 vs. control 1.8 +/- 0.9; NS). Within the CF group, glycaemic status had no impact on HOMA-IR (mU/mmol): 2.2 +/- 1.2 (normal glucose tolerance); 2.0 +/- 1.0 (impaired glucose tolerance); and 2.3 +/- 1.1 (diabetic glucose tolerance). -cell function (mU/mmol) was not only significantly lower in the CF group (CF 1.65 +/- 1.8; P < 0.001) but also in the CF group with normal glucose tolerance (2.25 +/- 2.10; P < 0.01) compared with healthy control (4.98 +/- 2.38). Mean plasma glucose concentrations were generally higher and mean plasma insulin concentrations lower in the CF group as a whole when compared with normal healthy controls. Within the CF group, there was a progressive decline in glucose-induced insulin release with worsening glycaemic status.

CONCLUSIONS

A lack of difference in peripheral IR, measured using HOMA-IR, in the CF group and healthy controls or within the CF group with differing glycaemic status suggests that IR does not have a significant role in the pathogenesis of CFRD. Pancreatic -cell function, already subnormal in CF patients with OGTT-defined normal glucose tolerance status, deteriorated further with worsening glycaemic status. This suggests that insulinopenia plays a prominent role in the pathogenesis of glucose intolerance and subsequent development of CFRD.

Five novel alternatively spliced transcripts of DNA (cytosine-5) methyltransferase 2 in human peripheral blood leukocytes

Alternative splicing of RNA molecules transcribed from DNA (cytosine-5) methyltransferases has been proposed as a mechanism by which methylation is able to effect diverse biological processes in higher eukaryotes. This study has investigated transcriptional versatility of DNA (cytosine-5) methyltransferase 2, which may methylate cytosine residues within 5'-CCTGG-3' pentanucleotides in regions of the human genome devoid of 5'-CG-3' methylation. Five novel splice variants of DNA (cytosine-5) methyltransferase 2 were identified in the peripheral blood leukocytes of healthy subjects following cloning and sequencing of RT-PCR products amplified using gene specific oligodeoxyribonucleotide primers. The generation of some of these splice variants may be influenced by the formation of secondary structures within pre-mRNA due to the repetition of sequences flanking alternatively spliced exons in a reverse and complementary orientation on the same strand. These findings enable novel approaches to investigate the role of RNA secondary structures in alternative splicing. The DNA (cytosine-5) methyltransferase 2 splice variants are generated in all the major cell types of peripheral blood, as well as in neoplastic lymphoid cells indicating that they are unlikely to generate proteins involved in control of the cell cycle or cellular differentiation. Interestingly, the gene products generated by some splice variants completely or partially lack highly conserved amino acid motifs shown to be important for the catalysis of cytosine methylation. The possibility cannot be excluded, therefore, that alternative splicing of DNA (cytosine-5) methyltransferase 2 pre-mRNA may generate protein isoforms which have different methylating capabilities or which are involved in biological processes other than the catalysis of cytosine methylation.