MedSecurance Project: Advanced Security-for-Safety Assurance for Medical Device IoT (IoMT)

The MedSecurance project focus on identifying new challenges in cyber security with focus on hardware and software medical devices in the context of emerging healthcare architectures. In addition, the project will review best practice and identify gaps in the guidance, particularly the guidance stipulated by the medical device regulation and directives. Finally, the project will develop comprehensive methodology and tooling for the engineering of trustworthy networks of inter-operating medical devices, that shall have security-for-safety by design, with a strategy for device certification and certifiable dynamic network composition, ensuring that patient safety is safeguarded from malicious cyber actors and technology "accidents".

Local Hemodynamic Conditions Associated with Focal Changes in the Intracranial Aneurysm Wall

BACKGROUND AND PURPOSE

Aneurysm hemodynamics has been associated with wall histology and inflammation. We investigated associations between local hemodynamics and focal wall changes visible intraoperatively.

MATERIALS AND METHODS

Computational fluid dynamics models were constructed from 3D images of 65 aneurysms treated surgically. Aneurysm regions with different visual appearances were identified in intraoperative videos: 1) "atherosclerotic" (yellow), 2) "hyperplastic" (white), 3) "thin" (red), 4) rupture site, and 5) "normal" (similar to parent artery), They were marked on 3D reconstructions. Regional hemodynamics was characterized by the following: wall shear stress, oscillatory shear index, relative residence time, wall shear stress gradient and divergence, gradient oscillatory number, and dynamic pressure; these were compared using the Mann-Whitney test.

RESULTS

Hyperplastic regions had lower average wall shear stress (P = .005) and pressure (P = .009) than normal regions. Flow conditions in atherosclerotic and hyperplastic regions were similar but had higher average relative residence time (P = .03) and oscillatory shear index (P = .04) than thin regions. Hyperplastic regions also had a higher average gradient oscillatory number (P = .002) than thin regions. Thin regions had lower average relative residence time (P < .001), oscillatory shear index (P = .006), and gradient oscillatory number (P < .001) than normal regions, and higher average wall shear stress (P = .006) and pressure (P = .009) than hyperplastic regions. Thin regions tended to be aligned with the flow stream, while atherosclerotic and hyperplastic regions tended to be aligned with recirculation zones.

CONCLUSIONS

Local hemodynamics is associated with visible focal wall changes. Slow swirling flow with low and oscillatory wall shear stress was associated with atherosclerotic and hyperplastic changes. High flow conditions prevalent in regions near the flow impingement site characterized by higher and less oscillatory wall shear stress were associated with local "thinning" of the wall.

Responsiveness to oral prednisolone in severe asthma is related to the degree of eosinophilic airway inflammation

BACKGROUND

Patients with severe asthma appear relatively corticosteroid resistant. Corticosteroid responsiveness is closely related to the degree of eosinophilic airway inflammation. The extent to which eosinophilic airway inflammation in severe asthma responds to treatment with systemic corticosteroids is not clear.

OBJECTIVE

To relate the physiological and inflammatory response to systemic corticosteroids in asthma to disease severity and the baseline extent of eosinophilic inflammation.

METHODS

Patients with mild/moderate and severe asthma were investigated before and after 2 weeks of oral prednisolone (Clintrials.gov NCT00331058 and NCT00327197). We pooled the results from two studies with common protocols. The US study contained two independent centres and the UK one independent centre. The effect of oral corticosteroids on FEV₁ , Pc20, airway inflammation and serum cytokines was investigated. Baseline measurements were compared with healthy subjects.

RESULTS

Thirty-two mild/moderate asthmatics, 50 severe asthmatics and 35 healthy subjects took part. At baseline, both groups of asthmatics had a lower FEV₁ and Pc20 and increased eosinophilic inflammation compared to healthy subjects. The severe group had a lower FEV₁ and more eosinophilic inflammation compared to mild/moderate asthmatics. Oral prednisolone caused a similar degree of suppression of eosinophilic inflammation in all compartments in both groups of asthmatics. There were small improvements in FEV₁ and Pc20 for both mild/ moderate and severe asthmatics with a correlation between the baseline eosinophilic inflammation and the change in FEV₁ . There was a ~50% reduction in the serum concentration of CXCL10 (IP-10), CCL22 (MDC), CCL17 (TARC), CCL-2 (MCP-1) and CCL-13 (MCP-4) in both asthma groups after oral corticosteroids.

CONCLUSIONS AND CLINICAL RELEVANCE

Disease severity does not influence the response to systemic corticosteroids. The study does not therefore support the concept that severe asthma is associated with corticosteroid resistance. Only baseline eosinophilic inflammation was associated with the physiological response to corticosteroids, confirming the importance of measuring eosinophilic inflammation to guide corticosteroid use.

Clinical characteristics and airway inflammation profile of COPD persistent sputum producers

BACKGROUND

COPD patients with chronic bronchitis include a subgroup with persistent sputum production on most or every day. We hypothesized that COPD patients with persistent sputum production have a different profile of airway inflammation, and more severe clinical characteristics.

OBJECTIVE

To compare the airway inflammation profile and clinical characteristics of COPD persistent and non-persistent sputum producers.

METHODS

COPD persistent sputum producers (n = 26) and non-persistent sputum producers (n = 26) underwent sputum induction and pulmonary function tests. Exacerbation history was recorded; the St. George's Respiratory Questionnaire, Modified Medical Research Council Dyspnoea scale and COPD Assessment Tool were completed. 33 COPD patients provided sputum for bacteriology.

RESULTS

Persistent sputum producers had lower post-bronchodilator FEV1% predicted (p = 0.01), diffusion capacity (p = 0.04), 6 min walk test distance (p = 0.05), and higher closing volume (p = 0.01), BODE index (p = 0.01), rate of bacterial colonization (p = 0.004) and exacerbations (p = 0.03) compared to non-persistent sputum producers. The mean SGRQ and CAT scores were higher in persistent sputum producers (p = 0.01 and 0.03 respectively). Sputum neutrophil and eosinophil total cell counts were higher in persistent sputum producers (p = 0.02 and 0.05 respectively). Sputum levels of eotaxin (p = 0.02), MCP-1 (p = 0.02), TNF-α (p = 0.03) and IL-6 (p = 0.05) were higher in persistent sputum producers.

CONCLUSION

COPD persistent sputum producers have more severe clinical characteristics and increased concentrations of some inflammatory mediators in the airways.

Radiological predictors of cytoreductive outcomes in patients with advanced ovarian cancer

OBJECTIVE

To assess site of disease on preoperative computed tomography (CT) to predict surgical debulking in patients with ovarian cancer.

DESIGN

Two-phase retrospective cohort study.

SETTING

West London Gynaecological Cancer Centre, UK.

POPULATION

Women with stage 3 or 4, ovarian, fallopian or primary peritoneal cancer undergoing cytoreductive surgery.

METHODS

Preoperative CT images were reviewed by experienced radiologists to assess the presence or absence of disease at predetermined sites. Multivariable stepwise logistic regression models determined sites of disease which were significantly associated with surgical outcomes in the test (n = 111) and validation (n = 70) sets.

MAIN OUTCOME MEASURES

Sensitivity and specificity of CT in predicting surgical outcome.

RESULTS

Stepwise logistic regression identified that the presence of lung metastasis, pleural effusion, deposits on the large-bowel mesentery and small-bowel mesentery, and infrarenal para-aortic nodes were associated with debulking status. Logistic regression determined a surgical predictive score which was able to significantly predict suboptimal debulking (n = 94, P = 0.0001) with an area under the curve (AUC) of 0.749 (95% confidence interval [95% CI]: 0.652, 0.846) and a sensitivity of 69.2%, specificity of 71.4%, positive predictive value of 75.0% and negative predictive value of 65.2%. These results remained significant in a recent validation set. There was a significant difference in residual disease volume in the test and validation sets (P < 0.001) in keeping with improved optimal debulking rates.

CONCLUSIONS

The presence of disease at some sites on preoperative CT scan is significantly associated with suboptimal debulking and may be an indication for a change in surgical planning.

MRI appearances of benign uterine disease

Benign uterine disease is a common entity affecting women of all ages. Ultrasound has historically been the predominant imaging method used in the evaluation of benign gynaecological disease, magnetic resonance imaging (MRI) being reserved for use in the staging of malignant uterine and cervical disease. MRI is now increasingly used in the diagnosis of benign uterine disease as well as a tool for problem-solving in cases of diagnostic dilemma. It allows detailed assessment of benign conditions, such as endometrial lesions, leiomyomas, and adenomyosis, and can be helpful in the stratification of patients to different treatment modalities, including surgical resection, uterine artery embolization, and medical therapies. In this article, we review the MRI findings in the common benign uterine diseases.

A high-fat-diet-induced cognitive deficit in rats that is not prevented by improving insulin sensitivity with metformin

AIMS/HYPOTHESIS

We previously demonstrated that animals fed a high-fat (HF) diet for 10 weeks developed insulin resistance and behavioural inflexibility. We hypothesised that intervention with metformin would diminish the HF-feeding-evoked cognitive deficit by improving insulin sensitivity.

METHODS

Rats were trained in an operant-based matching and non-matching to position task (MTP/NMTP). Animals received an HF (45% of kJ as lard; n = 24), standard chow (SC; n = 16), HF + metformin (144 mg/kg in diet; n = 20) or SC + metformin (144 mg/kg in diet; n = 16) diet for 10 weeks before retesting. Body weight and plasma glucose, insulin and leptin were measured. Protein lysates from various brain areas were analysed for alterations in intracellular signalling or production of synaptic proteins.

RESULTS

HF-fed animals developed insulin resistance and an impairment in switching task contingency from matching to non-matching paradigm. Metformin attenuated the insulin resistance and weight gain associated with HF feeding, but had no effect on performance in either MTP or NMTP tasks. No major alteration in proteins associated with insulin signalling or synaptic function was detected in response to HF diet in the hypothalamus, hippocampus, striatum or cortex.

CONCLUSIONS/INTERPRETATION

Metformin prevented the metabolic but not cognitive alterations associated with HF feeding. The HF diet protocol did not change basal insulin signalling in the brain, suggesting that the brain did not develop insulin resistance. These findings indicate that HF diet has deleterious effects on neuronal function over and above those related to insulin resistance and suggest that weight loss may not be sufficient to reverse some damaging effects of poor diet.

Perioperative heparin-therapy inhibits late death from metastatic cancer

Low-dose heparin prophylaxis reduces postoperative death from fatal pulmonary embolism and its long-term anti-cancer effect has now been assessed in a retrospective study of 1250 patients, 336 of whom (30%) underwent operation for cancer. There was a striking reduction in three year mortality amongst those patients who received low dose heparin compared to unteated controls (7.6% vs. 12.5%, P=0.005). Death from disseminated malignancy was halved (9.2% vs. 21.4%). The mechanism remains unclear, but may reflect either the antithrombotic actions of heparin or a direct antitumour cell effect.

Localization of expression of fibroblast growth-factors and their receptors in pancreatic adenocarcinoma by in-situ hybridization

Growth factors may play a role in autocrine or paracrine growth control of tumour cells. We have now examined the expression pattern in vivo by in situ hybridization (ISH) on a series of 13 ductal adenocarcinomas of the pancreas using the non-radioactive digoxigenin system to generate specific antisense orientated riboprobes for FGF-1 and FGF-2, and the four FGFRs (FGFR-1, -2, -3 and -4). We confirmed the expression of both FGF/FGFR by tumour cells, with the potential of a potential autocrine loops in 46% of the cases studied. FGF-2 and FGFR-3 were the most commonly expressed ligand and receptor (46% and 76% respectively). Endothelial cells lining vessels within an around invasive tumours were frequently positive for expression of FGFR-1 and/or FGFR-3. In the normal pancreas remote from the tumour, the acinar cells were found to have a heterogeneous expression pattern for FGFRs while duct cells, islet cells and stromal components including nerves and vascular endothelium were negative. The data suggest a role for FGFs and their high affinity receptors in the control of growth of human pancreatic adenocarcinoma and its supporting stroma.

Frequency multiplexed superconducting quantum interference device readout of large bolometer arrays for cosmic microwave background measurements

A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.

Neuronal membranes are key to the pathogenesis of Alzheimer's disease: the role of both raft and non-raft membrane domains

Membrane rafts are sterol- and sphingolipid-enriched domains that compartmentalize cellular processes. Membrane rafts isolated from post-mortem AD brain are enriched in both β-amyloid and phosphorylated tau. Proteolytic processing of APP to generate β-amyloid, the principle component of amyloid plaques, can occur in membrane rafts, implicating them in the pathogenesis of Alzheimer's disease (AD). Secondary to their role in β-amyloid generation, membrane rafts have more recently been implicated in the accumulation, aggregation and degradation of β-amyloid, with evidence supporting a specific role for membrane raft gangliosides in the binding and aggregation of β-amyloid. In addition, membrane domain composition has a direct impact on both the generation of β-amyloid and its subsequent toxic actions and as such is a key target for the development of therapeutic strategies. This mini-review will focus on recent advances in our understanding of the relevance of membrane composition, of both raft and non-raft domains, to AD progression in models and in human disease. We will discuss how manipulation of membrane composition can alter both the proteolytic processing of APP and the subsequent binding and aggregation of β-amyloid peptide.

Hysterosalpingogram: an essential examination following Essure hysteroscopic sterilisation

OBJECTIVES

The aim of this study was to describe our experience of imaging following hysteroscopic sterilisation with the Essure (Conceptus Inc., Mountain View, San Carlos, CA) microinsert, and to underline the importance of a carefully performed follow-up hysterosalpingogram (HSG) in the management of these patients.

METHODS

18 women underwent the procedure and all returned for follow-up HSG. A standard HSG technique was used and views were acquired to establish microinsert position and tubal occlusion.

RESULTS

In 16 of the 18 women, adequate microinsert positioning and bilateral tubal occlusion was present. In one woman, a unilateral microinsert occluded the fallopian tube, whereas the other fallopian tube was ligated with a clip. The final patient underwent two studies; both showed well-positioned microinserts but unilateral free spill from the right fallopian tube. There are no reported pregnancies thus far.

CONCLUSION

Essure sterilisation coils have a unique appearance when radiographed and are an effective means of permanently occluding the fallopian tubes. HSG is a rapid and safe method of confirming satisfactory placement and tubal occlusion. Non-HSG imaging techniques are suboptimal at detecting patent fallopian tubes and expose patients to the risk of an unwanted and potentially complicated pregnancy.

Integration of functional bacterial artificial chromosomes into human cord blood-derived multipotent stem cells

Stem cells from a patient with a genetic disease could be used for cell therapy if it were possible to insert a functional copy of the defective gene. In this study, we investigate the transfection and subsequent integration of large genomic fragments into human cord blood-derived multipotent stem cells. We describe for the first time the creation of clonal stem cells carrying a human bacterial artificial chromosome (BAC) containing the Friedreich ataxia locus with an enhanced green fluorescent protein (EGFP) reporter gene fused to exon 5a of the frataxin (FXN) gene. Integration of the BAC into the host cell genome was confirmed by PCR, Southern blot and fluorescent in situ hybridization analysis. Reverse transcription-PCR and flow cytometry confirmed expression of FXN-EGFP. Correct mitochondrial localization of the protein was confirmed using fluorescent microscopy. The transfected stem cells also retained the ability to differentiate into cells from all three germline layers, as demonstrated by the capacity to form neuron-specific beta-tubulin-expressing cells, Alizarin Red S-positive bone-like cells, and epithelial-like cells expressing surfactant protein C. This is the first study to demonstrate that cord blood-derived multipotent stem cells may be useful targets for gene therapy applications using large genomic loci.

Clinical trial: alvimopan for the management of post-operative ileus after abdominal surgery: results of an international randomized, double-blind, multicentre, placebo-controlled clinical study

BACKGROUND

Post-operative ileus (POI) affects most patients undergoing abdominal surgery.

AIM

To evaluate the effect of alvimopan, a peripherally acting mu-opioid receptor antagonist, on POI by negating the impact of opioids on gastrointestinal (GI) motility without affecting analgesia in patients outside North America.

METHODS

Adult subjects undergoing open abdominal surgery (n = 911) randomly received oral alvimopan 6 or 12 mg, or placebo, 2 h before, and twice daily following surgery. Opioids were administered as intravenous patient-controlled analgesia (PCA) or bolus injection. Time to recovery of GI function was assessed principally using composite endpoints in subjects undergoing bowel resection (n = 738).

RESULTS

A nonsignificant reduction in mean time to tolerate solid food and either first flatus or bowel movement (primary endpoint) was observed for both alvimopan 6 and 12 mg; 8.5 h (95% CI: 0.9, 16.0) and 4.8 h (95% CI: -3.2, 12.8), respectively. However, an exploratory post hoc analysis showed that alvimopan was more effective in the PCA (n = 317) group than in the non-PCA (n = 318) group. Alvimopan was well tolerated and did not reverse analgesia.

CONCLUSION

Although the significant clinical effect of alvimopan on reducing POI observed in previous trials was not reproduced, this trial suggests potential benefit in bowel resection patients who received PCA.

Interrater reliability of the Antipsychotic Non-Neurological Side-Effects Rating Scale measured in patients treated with clozapine

The Antipsychotic Non-Neurological Side-Effects Rating Scale (ANNSERS) was developed to provide a comprehensive measure for rating non-neurological adverse drug reactions (ADRs) to antipsychotics. Although there were already available measures that adequately rated specific non-neurological ADRs, such as sexual side effects, a need was identified for a scale that comprehensively rated the full range of non-neurological ADRs commonly seen across the spectrum of first and second generation antipsychotic drugs, including metabolic and autonomic ADRs. This article reports on work to establish the interrater reliability of an early version and a later, more comprehensive version of the ANNSERS (versions 1 and 2, v1 and v2, respectively). The measures were administered in London centres to patients treated with clozapine. Trained clinicians rated the patients simultaneously and independently. Interrater reliability on the scores was calculated using the kappa coefficient method. The results (mean kappa coefficients of 0.77 and 0.72, respectively) indicate that substantial interrater reliability was achieved for both versions. Items for which the main basis for rating was laboratory investigations rather than patient interview were largely excluded from this study, and kappas were also not calculated for items with a low frequency (less than 10%) of endorsement. Samples of patients on other antipsychotics would be required to reliably calculate kappa coefficients for these items. In conclusion, the ANNSERS represents a clinically applicable research innovation, with good interrater reliability on clinician judged items, which is now available for the comprehensive assessment of non-neurological ADRs to antipsychotics, to aid the processes of clinical audit, research and drug discovery.

COMT Val158Met and 5HTTLPR functional loci interact to predict persistence of anxiety across adolescence: results from the Victorian Adolescent Health Cohort Study

We investigated whether a composite genetic factor, based on the combined actions of catechol-O-methyltransferase (COMT) (Val(158)Met) and serotonin transporter (5HTTLPR) (Long-Short) functional loci, has a greater capacity to predict persistence of anxiety across adolescence than either locus in isolation. Analyses were performed on DNA collected from 962 young Australians participating in an eight-wave longitudinal study of mental health and well-being (Victorian Adolescent Health Cohort Study). When the effects of each locus were examined separately, small dose-response reductions in the odds of reporting persisting generalized (free-floating) anxiety across adolescence were observed for the COMT Met(158) [odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.76-0.95, P = 0.004] and 5HTTLPR Short alleles (OR = 0.88, CI = 0.79-0.99, P = 0.033). There was no evidence for a dose-response interaction effect between loci. However, there was a double-recessive interaction effect in which the odds of reporting persisting generalized anxiety were more than twofold reduced (OR = 0.45, CI = 0.29-0.70, P < 0.001) among carriers homozygous for both the COMT Met(158) and the 5HTTLPR Short alleles (Met(158)Met + Short-Short) compared with the remaining cohort. The double-recessive effect remained after multivariate adjustment for a range of psychosocial predictors of anxiety. Exploratory stratified analyses suggested that genetic protection may be more pronounced under conditions of high stress (insecure attachments and sexual abuse), although strata differences did not reach statistical significance. By describing the interaction between genetic loci, it may be possible to describe composite genetic factors that have a more substantial impact on psychosocial development than individual loci alone, and in doing so, enhance understanding of the contribution of constitutional processes in mental health outcomes.

The problem of polygenic disease

Most diseases have a genetic component. In those caused by a mutation at a single locus and with a clear phenotype (Mendelian disorders) the molecular genetics approach is relatively simple. The identification and cloning of the mutated gene leads to a complete analysis of the underlying molecular pathology and usually explains variation in incidence and severity. However, most adult diseases are not of this type. Coronary heart disease, cancer, diabetes, arthritis and mental illness all have a genetic component but are rarely inherited in a Mendelian fashion. Multifactorial diseases have both genetic and environmental components which contribute in different proportions in a given patient or family. The genes involved may exert additive effects, or act synergistically. Other cases of the same disease may be entirely environmental in their causation. Molecular genetics facilitates investigation of the number of genes involved in cases of multifactorial disease, their relative weight in different families and in the community, and the nature of their interaction. One particularly powerful approach is to study a large family in which simple Mendelian segregation occurs for a disease which is more often complex or sporadic.