Transforaminal lumbar interbody fusion with placement of steerable banana cage: A single-center retrospective analysis of radiographic parameters of success

INTRODUCTION

The transforaminal lumbar interbody fusion (TLIF) is among the most utilized methods for the surgical treatment of lumbar degenerative disc disease. The TLIF has advanced significantly with several iterative changes since its inception in the early 1980s, with the advent of several generations of interbody types, shapes, and materials. Steerable curvilinear interbodies are among the most recent innovations in this space and may offer biomechanical advantages, namely in preservation of lumbar and segmental lordosis. While radiographic parameters have been investigated for other cage shapes and lumbar interbody fusion techniques, no study has investigated postoperative radiographic outcomes specific to TLIFs done with curvilinear interbodies.

METHODS

This study is a retrospective review of TLIFs performed with curvilinear interbodies between 2019 and 2022 at a single institution. Upright radiographs were obtained preoperatively and at several timepoints postoperatively. Radiographic variables including interspace height and segmental lordosis were collected.

RESULTS

26 surgeries with 32 curvilinear interbodies were performed across 3 years. There was significant increase in segmental lordosis at the L4-L5 (p = 0.0183) and L5-S1 levels (p = 0.004) as well as interspace height postoperatively at levels L3-L4 (p = 0.011) and L4-L5 (p = 0.002). Pain as measured with the numeric rating scale significantly improved in the overall cohort postoperatively (p<0.001).

CONCLUSIONS

TLIF with curvilinear interbody placement increases segmental lordosis and interspace height at the L4-L5 and L5-S1 levels, and increased interspace height at the L3-L4 and L4-L5 levels. Further investigation into additional radiographic parameters is warranted and expanded cohort size would benefit deeper analysis of other spinal levels.

IMPLICATIONS FOR PRACTICE

As an increasing number of cage designs and materials are brought to market, studies such as this allow for better understanding of cage specific outcomes allowing for better informed device selection.

Radiation Treatment Preparation Safety Risk Prediction

PURPOSE/OBJECTIVE(S)

To determine the effect of delays in radiation treatment preparation task timeliness on reported safety events.

MATERIALS/METHODS

For 2022, all patients treated at four community-based radiation oncology clinics were included for analysis. Safety reports which occurred during treatment preparation tasks (i.e., between CT simulation and the first treatment) were included for this analysis. Patients with a reported safety event were the report cohort and those without were the control cohort. Treatment preparation tasks are completed sequentially and included contouring, treatment planning, Radiation Oncologist review, Medical Physicist review, Therapist quality check. At baseline, each task was scheduled a standard interval for completion based on treatment technique. The time taken to complete each task was captured using ARIA v16.0 Care Path module (Varian Medical Systems, Palo Alto, CA) and extracted through database query. For each task, two metrics were quantified: Task (1) Completion Timeliness: the time (hours) to complete each task, relative to the time allocated to each task. A negative value indicated more time taken than scheduled. (2) Overall Timeliness: specific task timeliness (hours) relative to overall timeliness for the whole Care Path. A negative value indicated the tasks were behind schedule. A student's t-test with an alpha of 0.05 was used to indicate significance.

RESULTS

Over the study period, 66 courses had a reported treatment preparation safety event (report) and 2690 did not (control). Techniques include 54% and 56% 3DCRT, 35% and 35% IMRT, 3% and 3% SRS, and 6% and 8% SBRT, for the report and control groups, respectively. Disease sites include breast, GU, GI, head and neck, CNS, thoracic, skin, secondary, gynecological, sarcoma, and heme. Table 1 displays the timeliness for each of the five tasks. Of the courses with safety events, overall timeliness was significantly behind the control group from the in contouring, treatment planning, Radiation Oncologist review, and Medical Physicist review. Courses with safety events took significantly more time than scheduled early in treatment preparation with a significant increase at treatment planning and significantly less time towards the end with the therapist quality check.

CONCLUSION

Patient courses with reported safety events had significantly longer treatment planning times, and as a result inadequate time to perform each downstream pre-treatment activity. The implication of this analysis is that a flag could be created to indicate risk of a safety event early in the treatment preparation process.

Technical evaluation of a simulator for accurate reproduction of oscillometric blood pressure pulses, providing traceability for automated oscillometric sphygmomanometers

Oscillometric blood pressure measurement devices are not directly traceable to primary standards. Currently, device accuracy is measured by comparison between a sample device and reference measurements in a clinical trial. We researched in this study the potential for an alternative evaluation with a simulator. Our research simulator was studied for repeatability and accuracy in delivering simulated blood pressure pulses. Clinical cuff pressure measurements were obtained, along with simultaneous recordings of oscillometric pulse waveforms, spanning the clinical range of cuff pressures, pulse intervals and pulse shapes. Oscillometric pulse peak amplitudes ranged from 1.1 to 3.6 mmHg. Simulated repeatability results showed an average Standard Deviation (SD) for pulse peaks of 0.018 mmHg; 1.0% of peak amplitudes. Comparing simulated pulse shapes, the average repeat SD was 0.015 mmHg; 0.8% of the normalised pulse shapes. The simulated accuracy results had a mean error of - 0.014 ± 0.042 mmHg with a mean accuracy of 97.8%. For pulse shape the corresponding values were - 0.104 ± 0.071 mmHg with a mean accuracy of 95.4%. The correlation between the reference and simulated pulse shapes ranged from 0.991 to 0.996 (all p < 0.00003), with a mean 0.994. We conclude that oscillometric pulses can be reproduced with high repeatability and high accuracy with our research simulator. The extended uncertaintyU(psim) = 0.3 mmHg for the simulated pulses is dominated by the uncertainty (64%) of the clinical reference data. These results underpin the potential of the simulator to become a secondary standard for millions of oscillometric sphygmomanometers.

O-147 Genomic analyses in 101,127 UK women show that previously reported monogenic genes are not common causes of premature ovarian insufficiency

Study question

What is the penetrance of variants in previously reported genes for premature ovarian insufficiency (POI) in the general population?

Summary answer

Heterozygous genetic variants in previously reported monogenic genes are not a common, highly penetrant cause of POI.

What is known already

Premature ovarian insufficiency (POI), defined as menopause before 40, has been associated with variants in over 70 genes. However, the evidence to support the causality of individual genetic variants varies between studies. As genomic data becomes more accessible, it is essential to ascertain the penetrance of variants in the absence of family history information. We identified 75 genes associated with POI from the literature, including family segregation studies, consanguineous pedigrees and cohort analyses of whole-exome/targeted sequencing data. Functional evaluation was also available for many of the genes.

Study design, size, duration

We used data from 101,127 females of European ancestry in the UK Biobank, to study the role of previously reported monogenic causal genes on ovarian function. We tested the association of 301 previously reported variants with POI and ANM, plus more than 2.5 million rare variants which were annotated and had not been implicated in POI previously. Genomic variants were tested individually and also combined into a gene burden test.

Participants/materials, setting, methods

Age at natural menopause (ANM) was derived from self-reported questionnaire data from the age at last menstrual period, excluding those with surgical menopause or taking hormone replacement therapy. POI cases were classified as women with ANM under 40 years (N = 2,213). Linked primary care records were used to identify a clinical cohort of POI cases, including primary amenorrhea (N = 113).

Main results and the role of chance

All of the previously reported individual variants we identified in our POI cases were also detected in the control group. Moreover, the gene burden tests were not associated with POI or ANM as a quantitative trait. Our results indicate that autosomal dominant causes of POI are rare; a single predicted loss-of-function (LOF) or non-synonymous genetic variant in one of the previously reported genes is generally not pathogenic.

Limitations, reasons for caution

The penetrance of monogenic disease-causing variants is likely to be lower in population-based cohorts such as UK Biobank than in clinically-ascertained cohorts.

Wider implications of the findings

Heterozygous LOF or non-synonymous variants in previously reported POI genes should be interpreted with caution and are unlikely to cause POI. The findings have implications for clinicians diagnosing causes of POI.

Trial registration number

Not applicable

1005 HEALTH-RELATED QUALITY OF LIFE AND FUTURE RISK OF HEALTH OUTCOMES AMONG OLDER ADULTS LIVING IN AUSTRALIA AND THE UNITED STATES

Introduction

Poor health-related quality of life (HRQoL) is associated with higher morbidity and mortality in patient populations. However, whether HRQoL is associated with health outcomes among community-dwelling older people requires further investigation. This study aimed to examine whether HRQoL predicts cognitive decline, dementia, cardiovascular disease (CVD), and mortality in community-dwelling older people living in Australia and the United States.

Method

A cohort of 19,106 individuals from the ASPirin in Reducing Events in the Elderly (ASPREE) study, aged 65–98 years, initially free of dementia or CVD, and who completed the HRQoL 12-item short form (SF-12, version-2) at baseline (2010–2014), were followed until June 2017. The physical (PCS) and mental component scores (MCS) of SF-12 were generated using standardized norm-based method.

Results

Over a median of 4.7 years, there were 2,412 cognitive declines, 574 dementia, 922 incident CVD events, and 1,052 deaths. Using Cox proportional-hazard regression adjusted for a range of covariates, every 10-unit increase in PCS was associated with a 6% lower risk of cognitive decline, a 14% lower risk of incident CVD, and 17% lower risk of all-cause mortality, but was not associated with incident dementia. In contrast, higher MCS was only associated with a 12% and 15% lower risk of cognitive decline and dementia, respectively. Findings did not differ by sex.

Conclusion

Our study provides some of the first evidence that HRQoL can be used in combination with clinical data to identify the future risks of health outcomes among older individuals living in the community. Our findings support the decision of the Australian Commission on Safety and Quality in Health Care to incorporate the SF-12 into the annual Patient-Reported Outcome Measures (PROMs assessment.

POS1304 CORRELATION OF SKIN SCORES (LoSCAT) WITH PATIENT REPORTED OUTCOMES IN JUVENILE LOCALISED SCLERODERMA

Background

Juvenile localised scleroderma (JLS) or morphea is a rare condition, causing inflammation and fibrosis in skin and underlying tissues. A validated skin score (Localized Scleroderma Cutaneous Assessment Tool, LoSCAT) has been developed [1]. This tool has both activity (mLoSSi) and damage indices (LoSDI). Several patient-reported outcomes (PRO) have been studied in JLS including visual analogue scales (VAS), functional and health-related quality of life measures.

Objectives

To assess the associations between different PROs and the activity and damage indices of the LoSCAT.

Methods

Participants aged 4 to 17 were recruited from 3 tertiary paediatric rheumatology centres in the UK and attended 4 visits at 3 monthly intervals as part of a program of research on JLS. Patient-reported VAS (6 different scales), the Children’s Dermatology Life Quality Index (CDLQI) and Childhood Health Assessment Questionnaires (CHAQ) were completed at each visit. LoSCAT was completed by the two same clinicians throughout the study (both trained in skin score techniques). Pearson correlation coefficients were calculated between each PRO and each component of the LoSCAT.

Results

24 participants completed all 4 visits and 1 attended 3 visits. 20 participants were female (80%) and 5 were male (20%). Mean age at diagnosis was 7.6 years with mean disease duration of 4.9 years. Subtype of disease was linear head in 5/25 (20%), linear limb 12/25 (48%), generalised morphoea 1/25 (4%), mixed 5/25 (20%) and superficial plaque in 2/25 (8%). Table 1 shows the correlations with figures in bold highlighting positive correlations which were statistically significant (p<0.05) and medium-sized (r>0.3).

Table 1.

Correlation between patient reported outcomes and LoSCAT

PROTotal skin activity (mLoSSi)Total skin damage (LoSDI)r (95% CI)p-valuer (95% CI)p-valueCDLQI0.61 (0.02, 1.20)0.0440.42 (0.01, 0.83)0.044CHAQ0.30 (0.03, 0.57)0.0270.20 (-0.14, 0.54)0.244VAS 1: How much IMPACT has your disease had on your life in the PAST MONTH?0.49 (0.00, 0.98)0.0500.38 (0.06, 0.71)0.021VAS 2: How much has your condition (localized scleroderma) affected you OVERALL in the PAST MONTH?0.59 (0.09, 1.09)0.0220.42 (0.13, 0.72)0.005VAS 3: Have your lesions felt itchy and/or scratchy in PAST MONTH?0.40 (-0.01, 0.81)0.0560.31 (0.03, 0.59)0.028VAS 4: Have you felt numbness, tingling, and/or other “funny” feeling in or around your lesion in PAST MONTH?0.55 (0.04, 1.05)0.0330.33 (-0.04, 0.71)0.084VAS 5: How much WORRY do you have about LONG- -TERM problems from your disease?0.40 (-0.01, 0.81)0.0530.32 (0.00, 0.63)0.047VAS 6: How much WORRY do you have about problems from MEDICATIONS used to treat your condition?0.41 (0.00, 0.82)0.0500.29 (-0.09, 0.66)0.131

The VAS of symptoms of numbness/tingling showed a strong positive correlation with mLoSSi but a weak and/or non-significant correlation with LoSDI. VAS itchy/scratchy did not show a strong correlation with mLoSSi but showed a moderate correlation with LoSDI. Patient global VAS correlated with both mLoSSi and LoSDI, as did CDLQI. CHAQ correlated with activity only.

Conclusion

Symptoms within lesions are often interpreted as indicating disease activity. A previous study in adults and children showed itch positively correlated with mLoSSi suggesting it may be a marker of active disease [2]. However, in our study numbness/tingling correlated with disease activity whereas itch did not. Further work is required to understand whether itch correlates to both activity and damage and whether numbness/tingling is a better indicator of activity than itch. Limitations of our study include a heterogenous group of participants with longstanding high-burden disease.

References

[1]Arkachaisri et al. Rheumatology 2010. 49(2): 373-81.

[2]Klimas et al. Br J Derm 2015; 175:1329-1337

Acknowledgements

This study was funded by Scleroderma & Raynaud’s UK.

Disclosure of Interests

None declared

Vascular risk factors affect different brain regions in people with Alzheimer’s disease

Introduction

Vascular risk factors including hypertension, diabetes and dyslipidaemia promote diverse pathological mechanisms in the brain leading to cerebral hypoperfusion and ultimately cognitive decline in people. Medial temporal, medial frontal and anterior cingulate atrophy has been closely associated with diabetes and medial temporal lobe atrophy is associated with hypertension in people with Alzheimer’s disease (AD).

Objectives

To assess if hypertension, diabetes and dyslipidaemia have differential effects on different brain locations using brain imaging in people with AD.

Methods

The current study is based on [¹⁸F] fluorodeoxyglucose- positron emission tomography (FDG-PET) data of 970 participants from two large Phase III multi-centre clinical trials of a novel tau aggregation inhibitor drug Leuco-Methylthioninium (LMTX)meeting research criteria for mild to moderate AD. Vascular risk factor data including hypertension, diabetes and dyslipidaemia were collected and quantification of FDG PET hypo-metabolism was done by calculating Standardized Uptake Value Ratio(SUVR).

Results

Hypertension, diabetes and dyslipidaemia were found to have differential effects on brain locations in people with AD. When people with hypertension, diabetes and dyslipidaemia were compared to those without, mean SUVR was increased significantly in both left and right parietal and occipital lobes and decreased in left and right anterior cingulate gyri in hypertensives. SUVR was significantly higher in both left and right temporal lobes in diabetics andlower in both left and right anterior cingulate gyri in people with dyslipidaemia.

Conclusions

Vascular risk factors including hypertension, diabetes and dyslipidaemia have differential effects on different brain regions, measured using SUVR analysis of FDG-PET.

Disclosure

The FDG-PET data was taken from participants of two large phase III clinical trials sponsored by TauRx Therapeutics (Singapore). TauRx Therapeutics has contributed towards my studentship during my PhD but the data related to drug used in the clinical tria

POS0168 NON-INVASIVE IMAGING IN JUVENILE LOCALISED SCLERODERMA: HIGH-FREQUENCY ULTRASOUND, THERMOGRAPHY, LASER DOPPLER & MULTISPECTRAL IMAGING

Background

Outcome measures which can differentiate activity (inflammation) from damage (fibrosis/atrophy) would facilitate development of new treatment strategies in juvenile localized scleroderma (JLS) to target the inflammatory phase of the disease.

Objectives

To evaluate whether in JLS, non-invasive imaging modalities (high frequency ultrasounds (HFUS), multispectral imaging (MSI), laser doppler imaging (LDI) & infra-red thermography (IRT)) can detect differences between affected & non-affected skin, as a next step in developing these as outcome measures. Our hypothesis was that blood flow (and therefore temperature & oxygenation) would be increased in lesional skin.

Methods

Participants aged 4-17 were recruited from 3 paediatric rheumatology centres in the UK. For each participant, a single lesion was selected. HFUS (30MHz), MSI (bespoke camera and tuneable liquid crystal filter, coupled to custom analysis software, 500nm/710nm wavelengths), LDI and IRT imaging were performed at four sites relating to each lesion: two of affected skin (centre & inner edge of lesion) and two of non-affected skin (one cm from edge of lesion (‘outer’) & contralateral unaffected side). Imaging was performed at 4 visits at 3 monthly intervals. Mean values were compared between the four sites using data from all visits by mixed-effects linear regression to account for individual-level clustering.

Results

24 participants completed all 4 visits and 1 attended 3. 20 participants were female (80%) & 5 male (20%). Mean age at diagnosis was 7.6 years & disease duration 4.9 years. Subtype of disease was linear head in 5/25 (20%), linear limb 12/25 (48%), generalised morphea 1/25 (4%), mixed 5/25 (20%) and superficial plaque in 2/25 (8%).

Table 1 shows a subset of data. All 4 imaging techniques could detect differences between healthy (outer/contralateral) & affected skin (centre/inner edge). For HFUS, there was strong evidence of a difference between affected & unaffected skin (p<0.001) indicating affected skin is thinner than unaffected. Higher mean values of oxygenation, perfusion & temperature were observed in affected compared to non-affected skin in MSI, LDI and IRT respectively. There was no statistical difference seen between inner edge and centre of the lesion in any of the methods.

Table 1.

Mean differences between different locations for each imaging technique

Imaging techniqueLocationOverall mean difference (95% CI)p-valueHFUS (mm)Centre - Contralateral-0.34 (-0.46, -0.22)<0.001Inner edge - Contralateral-0.30 (-0.40, -0.20)<0.001Centre - Outer-0.35 (-0.46, -0.24)<0.001Inner edge - Outer-0.31 (-0.40, -0.21)<0.001Centre - Inner edge-0.04 (-0.10, 0.02)0.168MSI (rel units)Centre - Contralateral0.06 (0.03, 0.10)<0.001Inner edge - Contralateral0.06 (0.03, 0.09)<0.001Centre - Outer0.04 (0.01, 0.07)0.012Inner edge - Outer0.03 (0.00, 0.06)0.028Centre - Inner edge0.01 (0.00, 0.02)0.251LDI Relative perfusion unitsCentre - Contralateral44.8 (24.4, 65.2)<0.001Inner edge - Contralateral47.9 (21.0, 74.8)<0.001Centre - Outer19.1 (1.0, 37.1)0.039Inner edge - Outer24.8 (6.7, 42.9)0.007Centre - Inner edge-3.5 (-20.3, 13.2)0.679IRT oCCentre - Contralateral0.58 (0.24, 0.91)0.001Inner edge - Contralateral0.44 (0.13, 0.75)0.005Centre - Outer0.44 (0.22, 0.66)<0.001Inner edge - Outer0.30 (0.09, 0.52)0.006Centre - Inner edge0.14 (-0.05, 0.32)0.153

The overall mean difference is the measurement of the first location minus the measurement from the second location (e.g. centre minus contralateral), averaged across the four visits.

Conclusion

Our results suggest non-invasive imaging can detect differences between healthy & unaffected skin in JLS. Whether each technique is only measuring activity & not damage requires further evaluation. The leading edge of lesions has historically been considered as most active compared to the centre. However, no difference was seen between centre & inner edge measurements suggesting that in future studies, imaging protocols can be simplified.

Acknowledgements

This study was funded by Scleroderma & Raynaud’s UK.

Disclosure of Interests

None declared

Melanoma secretion of transforming growth factor-β2 leads to loss of epidermal AMBRA1 threatening epidermal integrity and facilitating tumour ulceration

BACKGROUND

For patients with early American Joint Committee on Cancer (AJCC)-stage melanoma the combined loss of the autophagy regulatory protein AMBRA1 and the terminal differentiation marker loricrin in the peritumoral epidermis is associated with a significantly increased risk of metastasis.

OBJECTIVES

The aim of the present study was to evaluate the potential contribution of melanoma paracrine transforming growth factor (TGF)-β signalling to the loss of AMBRA1 in the epidermis overlying the primary tumour and disruption of epidermal integrity.

METHODS

Immunohistochemistry was used to analyse AMBRA1 and TGF-β2 in a cohort of 109 AJCC all-stage melanomas, and TGF-β2 and claudin-1 in a cohort of 30 or 42 AJCC stage I melanomas, respectively, with known AMBRA1 and loricrin (AMLo) expression. Evidence of pre-ulceration was analysed in a cohort of 42 melanomas, with TGF-β2 signalling evaluated in primary keratinocytes.

RESULTS

Increased tumoral TGF-β2 was significantly associated with loss of peritumoral AMBRA1 (P < 0·05), ulceration (P < 0·001), AMLo high-risk status (P < 0·05) and metastasis (P < 0·01). TGF-β2 treatment of keratinocytes resulted in downregulation of AMBRA1, loricrin and claudin-1, while knockdown of AMBRA1 was associated with decreased expression of claudin-1 and increased proliferation of keratinocytes (P < 0·05). Importantly, we show loss of AMBRA1 in the peritumoral epidermis was associated with decreased claudin-1 expression (P < 0·05), parakeratosis (P < 0·01) and cleft formation in the dermoepidermal junction (P < 0·05).

CONCLUSIONS

Collectively, these data suggest a paracrine mechanism whereby TGF-β2 causes loss of AMBRA1 overlying high-risk AJCC early-stage melanomas and reduced epidermal integrity, thereby facilitating erosion of the epidermis and tumour ulceration.

The detection of germline and somatic BRCA1/2 genetic variants through parallel testing of patients with high-grade serous ovarian cancer: a national retrospective audit

Objective

To determine the frequency of germline and somatic pathogenic BRCA1 and BRCA2 variants in patients with high‐grade serous ovarian cancer tested by next‐generation sequencing (NGS), with the aim of defining the best strategy to be implemented in future routine testing.

Design

National retrospective audit.

Setting

The All Wales Medical Genomics Service (AWMGS).

Population

Patients with high‐grade serous ovarian/fallopian tube/peritoneal cancer referred by oncologists to the AWMGS between February 2015 and February 2021 for germline and/or tumour testing of the BRCA1 and BRCA2 genes by NGS.

Methods

Analysis of NGS data from germline and/or tumour testing.

Main outcome measures

Frequency of BRCA1 and BRCA2 pathogenic variants.

Results

The overall observed germline/somatic pathogenic variant detection rate was 11.6% in the 844 patients included in this study, with a 9.2% (73/791) germline pathogenic variant detection rate. Parallel tumour and germline testing was carried out for 169 patients and the overall pathogenic variant detection rate for this cohort was 14.8%, with 6.5% (11/169) shown to have a somatic pathogenic variant. Two BRCA1 dosage variants were found during germline screens, representing 2.0% (2/98) of patients with a pathogenic variant that would have been missed through tumour testing alone.

Conclusions

Parallel germline and tumour BRCA1 and BRCA2 testing maximises the detection of pathogenic variants in patients with high‐grade serous ovarian cancer.

Tweetable abstract

Parallel germline and tumour testing maximises BRCA pathogenic variant detection in ovarian cancer.

Parallel germline and tumour testing maximises BRCA pathogenic variant detection in ovarian cancer.

Linked article This article is commented on by C Gourley, p. 443 in this issue. To view this mini commentary visit https://doi.org/10.1111/1471-0528.16978.

Accelerated Epigenetic Aging in Peripheral Blood does not Predict Dementia Risk

BACKGROUND

There is strong evidence that epigenetic age acceleration is associated with increased risk of later-life diseases and all-cause mortality. However, there is currently limited evidence that suggests accelerated epigenetic age is associated with dementia risk.

OBJECTIVE

This study aims to clarify whether epigenetic biomarkers of accelerated aging can predict dementia risk, which is an important consideration as aging is the greatest risk factor for the disease.

METHODS

DNA methylation was measured in peripheral blood samples provided by 160 participants from the ASPirin in Reducing Events in the Elderly study, including 73 pre-symptomatic dementia cases and 87 controls matched for age, sex, and smoking and education status. Epigenetic age was calculated using Horvath, Hannum, GrimAge and PhenoAge DNA methylation clocks, and age acceleration (the disparity between chronological age and epigenetic age) was determined.

RESULTS

There was no difference in age acceleration between dementia cases and controls. In males, only Hannum's intrinsic epigenetic age acceleration was increased in pre-symptomatic dementia cases compared to controls (Δ +1.8 years, p = 0.03).

CONCLUSION

These findings provide no strong evidence that accelerated epigenetic aging measured in peripheral blood can predict dementia risk.

Temperature response to cold challenge and mobile phone thermography as outcome measures for systemic sclerosis-related Raynaud's phenomenon

Objectives: Objective outcome measures of systemic sclerosis (SSc)-related Raynaud's phenomenon (RP) are badly needed. Our objectives were to validate the thermographic response to a standard hand cold challenge as an outcome measure by assessing sensitivity to change, and to explore mobile phone thermography as a feasible, ambulatory tool.Method: Twelve patients with an SSc-spectrum disorder admitted for intravenous iloprost infusions underwent a standard cold challenge before and after one infusion. Thermographic measurements included area under the rewarming curve (AUC) and maximum rewarming temperature (MAX). Before and during another infusion, each patient underwent monitoring of finger skin temperature by two methods: continuous thermocouple recording (standard method) and mobile phone thermography.Results: All cold challenge summary measures, including AUC and MAX, increased after iloprost (most not significantly). However, when the response curves were modelled after averaging across fingers (linear mixed models, three versions), significant change was detected. For example, with Model 1 (no interaction between period and time), temperature was on average 1.67ºC [95% confidence interval (CI) 1.49-1.85, p < 0.001] higher post-iloprost. Mobile phone and thermocouple temperature measurements showed a strong estimated latent correlation (0.88, 95% CI 0.81-0.92). The estimated increases/hour were 0.25ºC (95% CI 0.05-0.45) for the thermocouple and 0.36ºC (95% CI 0.13-0.60) for mobile phone thermography.Conclusion: Our pilot study suggests that the thermographic response to a cold challenge is sensitive to change and mobile phone thermography could bring feasibility to thermographic parameters as outcome measures in later-phase, large-scale, community-based clinical trials of RP.

O40: PRE-OPERATIVE MANAGEMENT AND SENSITISATION IN VASCULARIZED COMPOSITE ALLOTRANSPLANTATION: A SYSTEMATIC REVIEW

Introduction

Vascularised composite allotransplantation (VCA) permits like-for-like reconstruction following extensive soft tissue injuries. The initial management of extensive soft tissue injury can lead to the development of anti-HLA antibodies through injury, transfusion and cadaveric grafting. The role of antibody-mediated rejection, donor-specific antibodies and graft rejection in the context of VCA remains unclear. This systematic review aimed to determine whether pre-operative management strategies influence immunological outcome following VCA.

Method

A systematic review of MEDLINE, EMBASE and CINAHL using a PRISMA-compliant methodology up to February 2019 was conducted. Pre-operative, procedural and long-term outcome data were collected and recorded for all VCA recipients on an individual patient basis.

Result

The search revealed 3,847 records of which 114 met inclusion criteria and reported clinical data related to 100 patients who underwent 129 VCA transplants. Trauma (50%) and burns (15%) were the most frequent indications for VCA. Of all 114 studies, only one reported acute resuscitative management. Fifteen patients (14.7%) were sensitized prior to reconstructive transplantation with an 80% incidence of acute rejection in the first post-operative year. Seven patients demonstrated graft vasculopathy, only one of whom had demonstrated panel reactive antibodies.

Conclusion

Currently employed acute management strategies predispose to the development of anti-HLA antibodies, adding to the already complex immunological challenge of VCA. Early appropriate care is warranted in patients with extensive soft tissue loss where the resuscitative needs should be balanced against strategies to mitigate the immunological burden, particularly as reconstructive transplantation becomes a feasible option for future soft tissue coverage.

Take-home message

Acute resuscitative management may sensitise potential transplant recipients following major soft tissue injury. Early appropriate care is warranted.

Herd manager attitudes and intentions regarding the selection of high-fertility EBV sires in Australia

Reproductive performance in dairy cattle has declined over the last 50 years as an unintended consequence of selection for high milk yield. Since the early 2000s, dairy geneticists have released successive versions of fertility estimated breeding values (EBV) to assist in reversing this trend. At the herd level, fertility EBV can help managers accelerate improvements in reproductive performance by acting as a second selection criteria when used in tandem with a breeding index. However, use of the fertility EBV in sire selection currently varies between herd managers. The aim of this study was to better understand the reasons why herd managers choose or do not choose to select high-fertility EBV sires, using the Theory of Planned Behavior (TPB) as a social research framework. Thirty-five Victorian dairy herd managers were recruited as part of a larger study investigating the daughter fertility Australian Breeding Value and interviewed using a series of questions examining TPB constructs. The interviews were recorded and transcribed using template analysis. A wide range of herd manager types were enrolled into the study, with representation from diverse systems. Out of the 35 herd managers, 27 included fertility in their list of high-priority breeding objectives. A wide variation in results was consistent with previous studies that have demonstrated marked heterogeneity in herd manager attitudes toward bull selection. Herd manager-perceived barriers to selection of sires with high daughter fertility EBV included a lack of high daughter fertility bulls with other desirable traits, a lack of trust in the fertility EBV or in the Australian EBV system, difficulty in interpreting international proofs, information overload, semen prices, low bull reliability, and difficulty in understanding bull catalogs. Not all herd managers found the process problematic, however, particularly if a breeding consultant was employed to select all or most of the sires. Herd manager-perceived barriers for choosing to select daughter fertility as a breeding objective include a lack of awareness of the EBV, a lack of interest in genetics in general, low confidence in the impact of genetic selection for fertility, and a feeling that fertility was not important for their production system. The results of this study suggest that animal geneticists and on-farm service providers need to work together to allow the opportunities arising from appropriate use of fertility EBV to be realized more broadly across the dairy industry.

Age-related changes in pulse risetime measured by multi-site photoplethysmography

OBJECTIVE

It is accepted that changes in the peripheral pulse waveform characteristics occur with ageing. Pulse risetime is one important feature which has clinical value. However, it is unclear how it varies across the full age spectrum from child to senior and for different peripheral measurement sites. The objectives of this study were to determine the association between age and pulse risetime characteristics over an 8-decade age range at the ears, fingers, and toes, and to consider effects arising from differences in systolic blood pressure (SBP), height and heart rate.

APPROACH

Multi-site photoplethysmography (MPPG) pulse waveforms were recorded non-invasively from the right and left ears, fingers, and toes of 304 normal healthy human subjects (range 6-87 years; 156 male and 148 female). SBP, height, and heart rate were also measured. Multi-site PPG pulse risetimes, and their site differences, were determined.

MAIN RESULTS

Univariate regression analysis showed positive correlations with risetime for age (ears, fingers and toes: + 0.8, + 1.9, and + 1.1 ms/year, respectively), SBP (+0.5, + 1.3, and + 0.9 ms/mmHg) and height (+0.5, + 1.2, and + 1.0 ms/cm), but with a clear inverse association with heart rate (-1.8, - 2.5, and - 1.6 ms min) (P < 0.0001). No significant differences between male and female subjects were found for pulse risetime.

SIGNIFICANCE

Normative multi-site PPG risetime characteristics have been defined in over 300 subjects and are shown to increase with age linearly up to the 8th decade. In contrast, we have shown that heart rate has a clear inverse relationship with risetime for all measurement sites.

Differential Transcription of Selected Cytokine and Neuroactive Ligand-receptor Genes in Peripheral Leukocytes from Calves in Response to Cautery Disbudding

Simple Summary

Calf disbudding is a painful husbandry practice on dairy and beef cattle farms. Continuing efforts to enhance the accuracy of pain assessment can aid in the application of effective anti-nociceptive (analgesic) agents in non-verbal animals. The aim of this study was to evaluate the changes in the expression of genes involved in inflammation and pain sensitisation in response to removal of horn buds in calves, using hot-iron cauterization. The efficacy of an analgesic, meloxicam, was also tested in attenuating the changes in expression of the studied genes post-disbudding. It was revealed that cautery disbudding induces significant changes in the expression of genes involved in inflammation. Meloxicam was able to blunt the increased expression of some of the genes at 4 h and 24 h after disbudding, while it could not attenuate the increased expression of a few other genes associated with inflammation.

Abstract

Calf disbudding is a painful husbandry practice on dairy and beef cattle farms. An objective measurement of pain is useful to reliably evaluate the pain intensity and anti-nociceptive (analgesic) efficacy of therapeutic agents. The aim of this study was to investigate the changes in peripheral leucocyte inflammatory cytokine gene expression in calves after disbudding, and to assess whether the changes in cytokine gene expression could be an indicator of the efficacy of analgesic drugs. In a randomised controlled study, 16 calves (aged 31 to 41 days and weighing 58 to 73 kg), undergoing routine disbudding, were randomly allocated into two groups (n = 8 in each group). Calves in the control group received no analgesic, while those in the treatment group received 0.5 mg kg⁻¹ meloxicam subcutaneously prior to disbudding. Disbudding was performed using an electric debudder. Blood (10 mL) was sampled from the jugular vein just before and 4 and 24 h post-disbudding, RNA was extracted from leukocytes, and the transcription of 12 genes of interest was assessed using nCounter gene expression assay. The results showed significantly higher transcription (compared to baseline values) of the studied genes (except CRH, IFNγ, and IL10) in the control group calves at either 4 or 24 h post-disbudding. The administration of meloxicam one hour before disbudding significantly attenuated the upregulation of IL6, PGHS2, TAC1, NOS1, and CRH gene transcription post-disbudding, while it did not suppress the elevated transcription of acute and pro-inflammatory cytokines such as IL1β, IFNγ, IL8, and TNFα genes. In conclusion, nCounter gene expression assay seems to be a promising tool to study the expression of cytokine genes and thus could be used for the pre-clinical evaluation of novel analgesics.

Evaluation of the clinical and economic impact of delays to surgery in patients with periampullary cancer

Background

Early treatment is the only potential cure for periampullary cancer. The pathway to surgery is complex and involves multiple procedures across local and specialist hospitals. The aim of this study was to analyse variability within this pathway, and its impact on cost and outcomes.

Methods

Patients undergoing surgery for periampullary cancer (2011–2016) were identified retrospectively and their pathway to surgery was analysed. Patients who had early surgery (shortest quartile, Q1) were compared with those having late surgery (longest quartile, Q4).

Results

A total of 483 patients were included in the study, with 121 and 124 patients in Q1 and Q4 respectively. The median time from initial CT to surgery was 21 days for Q1 versus 112 days for Q4 (P < 0·001). Diagnostic delays were common in Q4; these patients required significantly more investigations than those in Q1 (endoscopic ultrasonography (EUS): 74·2 versus 18·2 per cent respectively, P < 0·001; MRI: 33·6 versus 20·6 per cent, P = 0·036). The median time to diagnostic EUS was 13 days in Q1 versus 59 days in Q4 (P < 0·001). Some 42·1 per cent of jaundiced patients in Q1 underwent preoperative biliary drainage, compared with all patients in Q4. There were significantly more unplanned admissions and associated longer duration of hospital stay per patient and costs in Q4 than in Q1 (median: 8 versus 3 days respectively; €5652 versus €2088; both P < 0·001). There was a higher likelihood of potentially curative surgery in Q1 (82·6 per cent versus 66·9 per cent in Q4; P = 0·005).

Conclusion

There is wide variation across the entire pathway, suggesting that multiple strategies are required to enable early surgery. Defining an effective pathway by anticipating the need for investigations and avoiding biliary drainage reduces unplanned admissions and costs and increases resection rates.

Biocompatibility of common implantable sensor materials in a tumor xenograft model

Real-time monitoring of tumor microenvironment parameters using an implanted biosensor could provide valuable information on the dynamic nature of a tumor's biology and its response to treatment. However, following implantation biosensors may lose functionality due to biofouling caused by the foreign body response (FBR). This study developed a novel tumor xenograft model to evaluate the potential of six biomaterials (silicon dioxide, silicon nitride, Parylene-C, Nafion, biocompatible EPOTEK epoxy resin, and platinum) to trigger a FBR when implanted into a solid tumor. Biomaterials were chosen based on their use in the construction of a novel biosensor, designed to measure spatial and temporal changes in intra-tumoral O2 , and pH. None of the biomaterials had any detrimental effect on tumor growth or body weight of the murine host. Immunohistochemistry showed no significant changes in tumor necrosis, hypoxic cell number, proliferation, apoptosis, immune cell infiltration, or collagen deposition. The absence of biofouling supports the use of these materials in biosensors; future investigations in preclinical cancer models are required, with a view to eventual applications in humans. To our knowledge this is the first documented investigation of the effects of modern biomaterials, used in the production of implantable sensors, on tumor tissue after implantation. © 2018 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials published by Wiley Periodicals, Inc. J Biomed Mater Res Part B, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1620-1633, 2019.

A Novel Translational Ovine Pulmonary Adenocarcinoma Model for Human Lung Cancer

In vitro cell line and in vivo murine models have historically dominated pre-clinical cancer research. These models can be expensive and time consuming and lead to only a small percentage of anti-cancer drugs gaining a license for human use. Large animal models that reflect human disease have high translational value; these can be used to overcome current pre-clinical research limitations through the integration of drug development techniques with surgical procedures and anesthetic protocols, along with emerging fields such as implantable medical devices. Ovine pulmonary adenocarcinoma (OPA) is a naturally-occurring lung cancer that is caused by the jaagsiekte sheep retrovirus. The disease has similar histological classification and oncogenic pathway activation to that of human lung adenocarcinomas making it a valuable model for studying human lung cancer. Developing OPA models to include techniques used in the treatment of human lung cancer would enhance its translational potential, making it an excellent research tool in assessing cancer therapeutics. In this study we developed a novel OPA model to validate the ability of miniaturized implantable O₂ and pH sensors to monitor the tumor microenvironment. Naturally-occurring pre-clinical OPA cases were obtained through an on-farm ultrasound screening programme. Sensors were implanted into OPA tumors of anesthetized sheep using a CT-guided trans-thoracic percutaneous implantation procedure. This study reports the findings from 9 sheep that received sensor implantations. Time taken from initial CT scans to the placement of a single sensor into an OPA tumor was 45 ± 5 min, with all implantations resulting in the successful delivery of sensors into tumors. Immediate post-implantation mild pneumothoraces occurred in 4 sheep, which was successfully managed in all cases. This is, to the best of our knowledge, the first description of the use of naturally-occurring OPA cases as a pre-clinical surgical model. Through the integration of techniques used in the treatment of human lung cancer patients, including ultrasound, general anesthesia, CT and surgery into the OPA model, we have demonstrated its translational potential. Although our research was tailored specifically for the implantation of sensors into lung tumors, we believe the model could also be developed for other pre-clinical applications.

Transcriptomic analysis of circulating neutrophils in metabolically stressed peripartal grazing dairy cows

The high metabolic demand during the transition into lactation places cows at greater risk of metabolic and infectious disease than at any other time in their lactation cycle. Additionally, a change occurs in the innate immune response during this period, which contributes to increased risk of disease. In the current study, we compared the transcriptomes of neutrophils from dairy cows divergent in their metabolic health post-calving. Cows (n = 5 per risk group) were selected from a parent experiment (n = 45 cows). Those with high or low concentrations of plasma nonesterified fatty acids, plasma β-hydroxybutyrate, and liver triacylglycerol in both wk 1 and 2 were deemed to be at "high risk" (HR) or "low risk" (LR) of metabolic dysfunction, respectively. Circulating neutrophils were isolated at 3 time points during the transition period (d 0 and wk 1 and 4 post-calving), and gene expression was analyzed using RNA sequencing. Differential gene expression between the risk groups was determined using edgeR (http://bioconductor.org), and pathway analysis was conducted using Ingenuity Pathway Analysis (Ingenuity Systems, Qiagen, Valencia, CA). Statistical analysis indicated no interaction between risk and week. Therefore, the overall effect of risk was analyzed across all time points. In total, 3,500 genes were differentially expressed between the HR and LR cows (false discovery rate < 0.05). Of these, 2,897 genes were identified by Ingenuity Pathway Analysis and used for pathway analysis. Of the relevant pathways identified, neutrophils isolated from HR cows showed downregulation of genes involved in the recruitment of granulocytes, interferon signaling, and apoptosis, and upregulation of genes involved in cell survival. The results indicate that metabolically stressed cows had reduced neutrophil function during the peripartum period, highlighting a potential relationship between subclinical metabolic disease and innate immune function that suggests that metabolic health negatively affects the innate immune system and may contribute to the state of immunosuppression during the peripartum period. In this way, the metabolic stress among the HR cows may reduce their ability to combat infection during the transition period.

Ovine Pulmonary Adenocarcinoma: A Unique Model to Improve Lung Cancer Research

Lung cancer represents a major worldwide health concern; although advances in patient management have improved outcomes for some patients, overall 5-year survival rates are only around 15%. In vitro studies and mouse models are commonly used to study lung cancer and their use has increased the molecular understanding of the disease. Unfortunately, mouse models are poor predictors of clinical outcome and seldom mimic advanced stages of the human disease. Animal models that more accurately reflect human disease are required for progress to be made in improving treatment outcomes and prognosis. Similarities in pulmonary anatomy and physiology potentially make sheep better models for studying human lung function and disease. Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring lung cancer that is caused by the jaagsiekte sheep retrovirus. The disease is endemic in many countries throughout the world and has several features in common with human lung adenocarcinomas, including histological classification and activation of common cellular signaling pathways. Here we discuss the in vivo and in vitro OPA models that are currently available and describe the advantages of using pre-clinical naturally occurring OPA cases as a translational animal model for human lung adenocarcinoma. The challenges and options for obtaining these OPA cases for research purposes, along with their use in developing novel techniques for the evaluation of chemotherapeutic agents or for monitoring the tumor microenvironment in response to treatment, are also discussed.

Development and characterisation of acquired radioresistant breast cancer cell lines

BACKGROUND

Radiotherapy plays an important role in the multimodal treatment of breast cancer. The response of a breast tumour to radiation depends not only on its innate radiosensitivity but also on tumour repopulation by cells that have developed radioresistance. Development of effective cancer treatments will require further molecular dissection of the processes that contribute to resistance.

METHODS

Radioresistant cell lines were established by exposing MDA-MB-231, MCF-7 and ZR-751 parental cells to increasing weekly doses of radiation. The development of radioresistance was evaluated through proliferation and colony formation assays. Phenotypic characterisation included migration and invasion assays and immunohistochemistry. Transcriptomic data were also generated for preliminary hypothesis generation involving pathway-focused analyses.

RESULTS

Proliferation and colony formation assays confirmed radioresistance. Radioresistant cells exhibited enhanced migration and invasion, with evidence of epithelial-to-mesenchymal-transition. Significantly, acquisition of radioresistance in MCF-7 and ZR-751 cell lines resulted in a loss of expression of both ERα and PgR and an increase in EGFR expression; based on transcriptomic data they changed subtype classification from their parental luminal A to HER2-overexpressing (MCF-7 RR) and normal-like (ZR-751 RR) subtypes, indicating the extent of phenotypic changes and cellular plasticity involved in this process. Radioresistant cell lines derived from ER+ cells also showed a shift from ER to EGFR signalling pathways with increased MAPK and PI3K activity.

CONCLUSIONS

This is the first study to date that extensively describes the development and characterisation of three novel radioresistant breast cancer cell lines through both genetic and phenotypic analysis. More changes were identified between parental cells and their radioresistant derivatives in the ER+ (MCF-7 and ZR-751) compared with the ER- cell line (MDA-MB-231) model; however, multiple and likely interrelated mechanisms were identified that may contribute to the development of acquired resistance to radiotherapy.

Complete Genome Sequence of the Telford Type S Strain of Mycobacterium avium subsp. paratuberculosis

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease (JD). Here, we report the complete genome sequence of Telford 9.2, a well-characterized representative strain of the M. avium subsp. paratuberculosis S subtype that is endemic in New Zealand and Australian sheep.

Preclinical Organotypic Models for the Assessment of Novel Cancer Therapeutics and Treatment

The immense costs in both financial terms and preclinical research effort that occur in the development of anticancer drugs are unfortunately not matched by a substantial increase in improved clinical therapies due to the high rate of failure during clinical trials. This may be due to issues with toxicity or lack of clinical effectiveness when the drug is evaluated in patients. Currently, much cancer research is driven by the need to develop therapies that can exploit cancer cell adaptations to conditions in the tumor microenvironment such as acidosis and hypoxia, the requirement for more-specific, targeted treatments, or the exploitation of 'precision medicine' that can target known genomic changes in patient DNA. The high attrition rate for novel anticancer therapies suggests that the preclinical methods used in screening anticancer drugs need improvement. This chapter considers the advantages and disadvantages of 3D organotypic models in both cancer research and cancer drug screening, particularly in the areas of targeted drugs and the exploitation of genomic changes that can be used for therapeutic advantage in precision medicine.

Abstract P3-12-24: Tumor-secreted predictive biomarkers of response to radiotherapy in breast cancer

Background:In breast cancer (BC), radiotherapy (RT) is used adjuvantly to prevent recurrence and also in the palliative setting. Clinical signs of RT response are often not apparent for several weeks post-treatment and we currently lack tools to predict or monitor tumor response to RT early during treatment. The aim was to identify tumor-secreted biomarkers whose release reflects response to RT, which could be monitored during treatment in the blood or intratumorally by an implantable biosensor, currently under development within the Implantable Microsystems for Personalised Anti-Cancer Therapy (IMPACT) program.

Methods: A series of experiments assessed the effect of different radiation doses (2-10Gy) on 3 human BC cell lines – MDA-MB-231 (ER-), MCF-7 (ER+) and HBL-100 (ER-) –, 1 canine breast cancer and 2 sheep lung cancer lines. Culture media was collected from each dose experiment at a range of post-radiation time-points (1-24 hours). Proteins were isolated from collected media for secretome mass spectrometry (MS) analysis. A subset of treatment/time conditions were repeated in the same BC cell lines and radioresistant (RR) derivatives from which RNA was extracted and analysed using Lexogen QuantSeq for whole-genome transcriptomics.In-lab candidate biomarker validation was carried out using immuhistochemistry (IHC), immunofluorescence (IF) and western blotting (WB) using validated antibodies. Levels of candidate biomarkers were also assessed in normal and untreated BC tissues using IHC. ELISA-based methods are currently under investigation for detection of the lead candidate biomarkers in the blood of large animal cancer models treated with RT.

Results: Biomarker discovery using the MS data revealed 4 promising candidates: EIF3G, SEC24C, YBX3 and TK1. These are released from BC and animal cancer cells sensitive to radiation in a dose-dependent manner 24 hours after treatment. Analysis of the transcriptomic data showed an 8-fold higher expression of the genes encoding the 4 candidates in the radio-sensitive parental cell lines compared to the RR cell lines. IF and WB confirmed lower intracellular expression of the 4 proteins in RR cells compared to the parental lines. WB of collected culture media confirmed release of each of the 4 candidates 24 hours after a 2Gy dose of radiation in only the parental lines. GAPDH was not found in these media samples, demonstrating that protein release was not due to cell lysis.

Conclusions:

· We have identified 4 promising biomarkers which are released from cancer cells sensitive to RT and not released from RR derivatives.

· All 4 candidates are released 24 hours after a 2Gy radiation dose, which fits with the current clinical dosing schedule where radiation is administered at 24 hour intervals. Ongoing work will elucidate if these biomarkers can be reliably detected in blood or intratumorally using implantable biosensors.

· There are currently no validated predictive tools to monitor RT response during treatment. If successfully validated, these biomarkers could have a clinical role in personalising RT dosing schedules and durations for solid tumors in the neoadjuvant and palliative setting, thus optimising treatment and preventing the administration of ineffective RT and its associated side effects.

Citation Format: Meehan J, Gray M, Turnbull AK, Martinez-Perez C, Bonello M, Ward C, Langdon SP, McLaughlin S, MacLennan M, Dixon JM, Wills J, Quinn N, Finich AJ, von Kriegsheim A, Cameron D, Kunkler IH, Murray A, Argyle D. Tumor-secreted predictive biomarkers of response to radiotherapy in breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-12-24.

Do entrepreneurial knowledge and innovative attitude overcome “imperfections” in the innovation process? Insights from SMEs in the UK and Italy

Purpose

Entrepreneurial knowledge spurs innovation and, in turn, generates a competitive advantage. This paper aims to explore if entrepreneurial knowledge combined with the attitude to innovate can overcome the key “imperfections” of the innovation process generated by dynamic, current technological progress in the knowledge-intensive sector. The “imperfections” identified in risk management, asymmetric information in the knowledge management process and hold-up problems can all disrupt collaborative partnerships and limit opportunities for innovation.

Design/methodology/approach

A theory-building approach is applied which offers a case study analysis of two small- to medium-sized enterprises (SMEs). These two SMEs operate in Europe but in two different territories: the UK and Italy. The study explores three key imperfections, risk management, asymmetric information in the knowledge management process and hold-up problems, which occur in the innovation process.

Findings

The entrepreneurs face these imperfections by adopting an open innovation model. Notwithstanding, both entrepreneurs had to deal with all “imperfections”, and their skills, attributes, attitude and aptitude allowed them to grow their business and continually develop new products. Therefore, the imperfections do not limit the innovative capacity of an entrepreneur but rather enhance their challengeable attitude. In this regard, the case studies induce a further analysis on entrepreneurial knowledge intertwined with entrepreneurial risk management and networking skills.

Research limitations/implications

The empirical significance of the two cases does not allow theorisation. However, this research offers interesting results which can be strengthened by a comparative case study with other countries or deeper investigation by applying a quantitative approach.

Originality/value

By leveraging entrepreneurial knowledge, the imperfections noted in the innovation process can be overcome. Entrepreneurial knowledge is recognised as the main asset of an enterprise if it is combined with external talent or human resources. Entrepreneurs aim to develop innovative approaches and ideas through establishing both formal and informal collaborative partnership relationships which are used thanks to the entrepreneurs’ networking skills, knowledge and abilities.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Innovative multi-site photoplethysmography measurement and analysis demonstrating increased arterial stiffness in paediatric heart transplant recipients

OBJECTIVE

It has been documented that heart transplantation in children is often complicated by arterial hypertension and increased arterial stiffness. We use innovative multi-site photoplethysmography (MPPG) pulse measurement and analysis technology to assess changes in arterial stiffness in paediatric heart transplant recipients (HTRs) in comparison with healthy control (HC) children.

APPROACH

A group of 20 HTRs (median age 13.5 years, eight male) were compared to an overall age- and gender-matched group of 161 HCs (median age 11.6 years, 74 male). Peripheral pulse was recorded bilaterally using MPPG at the ear lobe, index finger and great toe sites, along with an electrocardiogram cardiac timing reference. Segmental pulse arrival times between peripheral sites (finger-ear, PATf-e; toe-finger, PATt-f; and toe-ear PATt-e) were calculated as arterial stiffness measures, and differences between subject groups were tested using multivariate analysis. Normalised ear, finger and toe pulse shapes were also studied and compared between groups.

MAIN RESULTS

After correction for heart rate and diastolic and mean arterial blood pressures, the HTR group was found to have significantly lower segmental PATt-e and PATt-f measurements, with median values of 150 ms versus 172 ms in the HC group (p  =  0.02), and 104 ms versus 118 ms in the HC group (p  =  0.01), respectively, consistent with increased arterial stiffness in the patient group. The normalised ear, finger and toe sites showed only a mild elongation in each pulse rise time for the transplant group.

SIGNIFICANCE

This study shows that innovative and easy-to-do MPPG gives further evidence for increased arterial stiffness in children who have undergone successful cardiac transplantation.

A feasibility study of a novel low-level light therapy for digital ulcers in systemic sclerosis

Background: Locally acting, well-tolerated treatments for systemic sclerosis (SSc) digital ulcers (DUs) are needed.

Objectives: Our primary aim was to investigate the safety, feasibility, and tolerability of a novel low-level light therapy (LTTT). A secondary aim was to tentatively assess efficacy.

Methods: A custom-built device comprising infrared (850 nm), red (660 nm), and violet (405 nm) LEDs was utilized. DUs were irradiated with 10 J/cm² twice weekly for 3 weeks, with follow-up at weeks 4 and 8. Any safety concerns were documented. Patient opinion on time to deliver, feasibility, and pain visual analogue score (VAS; 0–100, 100 most severe) was collected. Patient and clinician DU global assessment VAS were documented. DUs were evaluated by laser Doppler perfusion imaging pre- and post-irradiation.

Results: In all, 14 DUs in eight patients received a total of 46 light exposures, with no safety concerns. All patients considered LTTT ‘took just the right amount of time’ and was ‘feasible’, with a low associated mean pain VAS of 1.6 (SD: 5.2). Patient and clinician global DC VAS improved during the study (mean change: –7.1 and –5.2, respectively, both p < .001). DU perfusion significantly increased post-irradiation.

Conclusions: LTTT for DUs is safe, feasible, and well tolerated. There was an early tentative suggestion of treatment efficacy.

Effect of Respiration on the Characteristic Ratios of Oscillometric Pulse Amplitude Envelope in Blood Pressure Measurement

Systolic and diastolic blood pressures (BPs) are important physiological parameters for disease diagnosis. Systolic and diastolic characteristic ratios derived from oscillometric pulse waveform have been widely used to estimate automated non-invasive BPs in oscillometric BP measurement devices. The oscillometric pulse waveform is easily influenced by respiration, which may cause variability to the characteristic ratios and subsequently BP measurement. This study quantitatively investigated how respiration patterns (i.e., normal breathing and deep breathing) affect the systolic and diastolic characteristic ratios. The study was performed with clinical data collected from 39 healthy subjects, and each subject conducted BP measurements during normal and deep breathings. Analytical results showed that the systolic characteristic ratio increased significantly from 0.52 ± 0.13 under normal breathing to 0.58 ± 0.14under deep breathing (p < 0.05), and the diastolic characteristic ratio was not significantly affected from 0.75 ± 0.12 under normal breathing to 0.76 ± 0.13 under deep breathing (p = 0.48). In conclusion, deep breathing significantly affected the systolic characteristic ratio, suggesting that automated oscillometric BP device which is validated under resting condition should be strictly used for measurements under resting condition.

Variation of the Korotkoff Stethoscope Sounds During Blood Pressure Measurement: Analysis Using a Convolutional Neural Network

Korotkoff sounds are known to change their characteristics during blood pressure (BP) measurement, resulting in some uncertainties for systolic and diastolic pressure (SBP and DBP) determinations. The aim of this study was to assess the variation of Korotkoff sounds during BP measurement by examining all stethoscope sounds associated with each heartbeat from above systole to below diastole during linear cuff deflation. Three repeat BP measurements were taken from 140 healthy subjects (age 21 to 73 years; 62 female and 78 male) by a trained observer, giving 420 measurements. During the BP measurements, the cuff pressure and stethoscope signals were simultaneously recorded digitally to a computer for subsequent analysis. Heartbeats were identified from the oscillometric cuff pressure pulses. The presence of each beat was used to create a time window (1 s, 2000 samples) centered on the oscillometric pulse peak for extracting beat-by-beat stethoscope sounds. A time-frequency two-dimensional matrix was obtained for the stethoscope sounds associated with each beat, and all beats between the manually determined SBPs and DBPs were labeled as "Korotkoff." A convolutional neural network was then used to analyze consistency in sound patterns that were associated with Korotkoff sounds. A 10-fold cross-validation strategy was applied to the stethoscope sounds from all 140 subjects, with the data from ten groups of 14 subjects being analyzed separately, allowing consistency to be evaluated between groups. Next, within-subject variation of the Korotkoff sounds analyzed from the three repeats was quantified, separately for each stethoscope sound beat. There was consistency between folds with no significant differences between groups of 14 subjects (P = 0.09 to P = 0.62). Our results showed that 80.7% beats at SBP and 69.5% at DBP were analyzed as Korotkoff sounds, with significant differences between adjacent beats at systole (13.1%, P = 0.001) and diastole (17.4%, P < 0.001). Results reached stability for SBP (97.8%, at sixth beat below SBP) and DBP (98.1%, at sixth beat above DBP) with no significant differences between adjacent beats (SBP P = 0.74; DBP P = 0.88). There were no significant differences at high-cuff pressures, but at low pressures close to diastole there was a small difference (3.3%, P = 0.02). In addition, greater within subject variability was observed at SBP (21.4%) and DBP (28.9%), with a significant difference between both (P < 0.02). In conclusion, this study has demonstrated that Korotkoff sounds can be consistently identified during the period below SBP and above DBP, but that at systole and diastole there can be substantial variations that are associated with high variation in the three repeat measurements in each subject.

Novel optical assessments of tissue composition and viability using fluorescence spectroscopy and tissue oxygenation spectrophotometry in patients with systemic sclerosis: a pilot study

OBJECTIVE

Patients with systemic sclerosis (SSc) experience significant morbidity and mortality, therefore, the development of tests to aid its early diagnosis are very important. The aim of this pilot study was to assess the diagnostic value of novel optical non-invasive skin fluorescence spectroscopy (FS) and tissue oxygen saturation (TOS) viability measurements in patients with established SSc.

APPROACH

Two groups were studied, comprising 14 SSc patients and nine healthy controls (93% and 73% females, respectively). FS and TOS measurements were collected from three body sites: the forearm, chest, and calf. Fluorescence intensities at wavelengths attributed to collagen, elastin, and L-tryptophan were computed, with adjustment for melanin, and a normalised combined fluorescence score (NCFS) was determined.

MAIN RESULTS

The NCFS was significantly higher (p  <  0.001) and the combined TOS significantly lower (p  <  0.001) in the SSc group. TOS measurements alone showed good classification accuracy (95.7%) at separating SSc from healthy control participants, with some clustering of values close to the 50% oxygenation level in both groups. When the composition and viability measures were combined and modelled using binary logistic regression, excellent results for the sample were obtained following leave one out cross validation (100%).

SIGNIFICANCE

The results of this pilot study demonstrate the potential diagnostic utility of FS and TOS assessments in SSc patients and further work is now needed to validate these techniques prospectively in a larger group of SSc patients across the spectrum of the disease, and also patients with other types of vasculopathy and conditions that can cause skin fibrosis.

Managing knowledge through social media

Purpose

The purpose of this paper is to conceptualise social media usage (SMU) as a contributory, knowledge management (KM) tool towards entrepreneurial behaviour amongst small- and medium-sized enterprises (SMEs). Although an underdeveloped concept in entrepreneurship, the conceptual analysis of KM presents evidence which links SMU as complementary to changing KM conventions.

Design/methodology/approach

The pertinent KM and SMU literatures of the SME context were reviewed to form an understanding of this context. Employing a mixed-methods approach, a pragmatic, thematic investigation of SMU-enhanced KM was facilitated.

Findings

Substantial benefits of innovative SMU, as a management tool towards SME entrepreneurialism, were witnessed. SMU enhances the administration of real-time knowledge, encouraging creativity. However, longer-term costs of employing requisite personnel, and anticipated organisational restructuring, present challenges. The paper identifies the potentials of social media technologies in overcoming KM issues. The authors propose a reasoned process model towards entrepreneurial exploitation by acknowledging systematic phases of research, concept, institutionalise, develop, target and assess, referred to as the RCIDTA model.

Practical implications

The authors argue that KM, through social media, facilitates interactions to execute innovative processes within SMEs ever-changing infrastructures. It also informs nascent entrepreneurs, in considering the benefits of systematic KM, and novel SMU, opportunities. The RCIDTA model for SMEs can be utilised in improving knowledge ecosystems of entrepreneurial SMEs, promoting innovation towards sustained organisation growth.

Originality/value

This paper embraces the growing approach of SMEs applying SMU. SMU and its cost efficiency support the start-up activity. This paper highlights central issues concerning the exploitation of sector-specific KM, including organisational strategy, structure, brand formation, fiscal and personnel resource allocation and market share.

Analysis of the Temporal Compressibility of Breast Tumour Marker Assays: Development of a “Near Patient” Assay

The aim of this study was to investigate whether immunoassays for circulating MUC1 antigen in breast cancer could be compressed in time so that serum level results would be made available during the time of the patient's visit to clinic.

Two assays were used: - The EMCA (Euro DPC) is a liquid phase immunoassay and the ELSA CA15-3 (CIS) is a double determinant solid phase immunoradiometric assay. The effects of shortened incubation times were investigated by assaying standards and unknown samples and comparing the results with those using the standard kit protocols. The binding kinetics of the monoclonal antibodies employed in the assays were analysed separately.

We conclude that the EMCA assay can be shortened to 35 min and we have attributed this to the fast binding kinetics inherent in a liquid phase assay. This shortened assay may produce the basis for a useful “near patient” assay. By comparison, the solid phase ELSA CA15-3 assay cannot be compressed without loss in assay performance.

A universal standard for the validation of blood pressure measuring devices: Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization (AAMI/ESH/ISO) Collaboration Statement

: In the last 30 years, several organizations, such as the US Association for the Advancement of Medical Instrumentation (AAMI), the British Hypertension Society, the European Society of Hypertension (ESH) Working Group on Blood Pressure (BP) Monitoring and the International Organization for Standardization (ISO) have developed protocols for clinical validation of BP measuring devices. However, it is recognized that science, as well as patients, consumers and manufacturers would be best served if all BP measuring devices were assessed for accuracy according to an agreed single validation protocol that had global acceptance. Therefore, an international initiative was taken by AAMI, ESH and ISO experts who agreed to develop a universal standard for device validation. This statement presents the key aspects of a validation procedure, which were agreed by the AAMI, ESH and ISO representatives as the basis for a single universal validation protocol. As soon as the AAMI/ESH/ISO standard is fully developed, this will be regarded as the single universal standard and will replace all other previous standards/protocols.

A Universal Standard for the Validation of Blood Pressure Measuring Devices: Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization (AAMI/ESH/ISO) Collaboration Statement

In the past 30 years, several organizations, such as the US Association for the Advancement of Medical Instrumentation (AAMI), the British Hypertension Society, the European Society of Hypertension (ESH) Working Group on Blood Pressure (BP) Monitoring, and the International Organization for Standardization (ISO), have developed protocols for clinical validation of BP measuring devices. However, it is recognized that science, as well as patients, consumers, and manufacturers, would be best served if all BP measuring devices were assessed for accuracy according to an agreed single validation protocol that had global acceptance. Therefore, an international initiative was taken by the AAMI, ESH, and ISO experts who agreed to develop a universal standard for device validation. This statement presents the key aspects of a validation procedure, which were agreed by the AAMI, ESH, and ISO representatives as the basis for a single universal validation protocol. As soon as the AAMI/ESH/ISO standard is fully developed, this will be regarded as the single universal standard and will replace all other previous standards/protocols.

External Trabeculectomy with T-Flux Implant

PURPOSE

To evaluate the efficacy and safety of T-Flux implant in nonpenetrating glaucoma surgery.

METHODS

This clinical interventional case series study included 35 eyes of 35 patients with medically uncontrolled primary open angle glaucoma. External trabeculectomy with T-Flux (ETTF) is a technique of nonpenetrating glaucoma surgery, in which after removing deep scleral tissue and un-roofing the canal of Schlemn (CS) the external trabecular tissue is peeled off to enhance the aqueous drainage without opening the anterior chamber. A non-absorbable T-Flux implant (IOL TECH Laboratories, France) was sutured in deep intrascleral space to keep it patent. Snellen's best-corrected visual acuity, slit lamp biomicroscopy, intraocular pressure (IOP), gonioscopy, funduscopy, and optic disc assessment were performed preoperatively and postoperatively at 1 day, 1 week, and 1, 3 , 6, and 12 months. Visual field testing was performed preoperatively and at 6 and 12 months postoperatively.

RESULTS

For three eyes, surgery was converted to standard trabeculectomy owing to the perforation of trabeculo-Descemet's membrane and iris prolapse and excluded from the study. The results of the remaining 32 eyes were included in the study. Preoperative IOP (mean +/- SD) of 32.88 +/- 5.7 mmHg decreased to 15.44 +/- 1.6 mmHg after 12 months. Ten eyes (28.6%) had microhyphema that resolved spontaneously; 3 eyes (8.6%) had microperforation without iris prolapse so ETTF was proceeded routinely. The preoperative number of antiglaucoma medications per patient reduced from (mean +/- SD) 2.74 +/- 0.61 to 0.11 +/- 0.32 postoperatively at 12 months. Visual acuity and visual fields remained stable.

CONCLUSIONS

ETTF appears to provide significant control of IOP and have low incidence of complications.