Comparison of laparoscopic cholecystectomy in children at paediatric centres and adult centres: a systematic review and meta-analysis

INTRODUCTION

Paediatric laparoscopic cholecystectomy (LC) is performed by both paediatric and adult surgeons. The aim of this review was to compare outcomes at paediatric centres (PCs) and adult centres (ACs).

METHODS

A literature search was conducted, in accordance with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines, for papers published between January 2000 and December 2020. Statistical analysis was performed using Stata® version 16 (StataCorp, College Station, TX, US).

RESULTS

A total of 92 studies involving 74,852 paediatric LCs met the inclusion criteria. Over half (59%) of the LCs were performed at ACs. No significant differences were noted in the male-to-female ratio, mean age or mean body mass index between PCs and ACs. The main indications were cholelithiasis (34.1% vs 34.4% respectively, p=0.83) and biliary dyskinesia (17.0% vs 23.5% respectively, p<0.01). There was no significant difference in the median inpatient stay (2.52 vs 2.44 days respectively, p=0.89). Bile duct injury was a major complication (0.80% vs 0.37% respectively, p<0.01). Reoperation rates (2.37% vs 0.74% respectively, p<0.01) and conversion to open surgery (1.97% vs 4.74% respectively, p<0.01) were also significantly different. Meta-analysis showed no significant difference in overall complications (p=0.92).

CONCLUSIONS

The number of LCs performed, intraoperative cholangiography use and conversion rates were higher at ACs whereas bile duct injury and reoperation rates were higher at PCs. Despite a higher incidence of bile duct injury at PCs, the incidence at both PCs and ACs was <1%. In complex cases, a joint operation by both paediatric and adult surgeons might be a better approach to further improve outcomes. Overall, LC was found to be a safe operation with comparable outcomes at PCs and ACs.

Landscaping tuberculosis multimorbidity: findings from a cross-sectional study in India

BACKGROUND

Multimorbidity, the concurrent presence of two or more chronic conditions is an emerging public health challenge. Till date, most of the research have focused on the presence and interaction of selected co-morbidities in tuberculosis (TB). There exist a critical knowledge gap on the magnitude of multimorbidity among TB patients and its impact on health outcomes.

METHODS

We undertook a cross-sectional study to assess the prevalence and patterns of multimorbidity among newly diagnosed TB patients in two states of India. A total of 323 patients were interviewed using a structured multimorbidity assessment questionnaire for primary care (MAQ-PC). MAQ-PC is already validated for Indian population and elicits 22 chronic conditions. We defined TB multimorbidity as the co-existence of TB with one or more chronic conditions and identified commonly occurring dyads (TB + single condition) and triads (TB + two conditions).

RESULTS

More than half (52%) of TB patients reported multimorbidity. Among dyads, depression, diabetes mellitus (DM), acid peptic disease (APD), hypertension, chronic alcoholism, arthritis and chronic back ache (CBA) were the most common co-occurring conditions while 'DM + arthritis', 'depression + APD', 'depression + DM' were the most commonly occurring triads among TB patients. Factors such as increasing age, low levels of education, alcohol abusers, drug-resistant TB and having health insurance were significantly associated with multimorbidity among TB patients.

CONCLUSIONS

Our findings suggest high prevalence of multimorbidity among newly diagnosed TB patients in India. The presence of concordant and discordant conditions with TB may increase the health complexity, thus necessitating appropriate care protocols. Given, the current situation, wherein TB and non-communicable diseases (NCD) services are delivered through collaborative framework between programmes, there is a need for addressing multimorbidity at the healthcare delivery level.

Review of management practices of sinogenic intracranial abscesses in children

OBJECTIVE

This study aimed to evaluate the management practices and outcomes in children with sinogenic intracranial suppuration.

METHOD

This was a retrospective cohort study in a single paediatric tertiary unit that included patients younger than 18 years with radiologically confirmed intracranial abscess, including subdural empyema and epidural or intraparenchymal abscess secondary to sinusitis. Main outcomes studied were rate of return to the operating theatre, length of hospital stay, death in less than 90 days and neurological disability at 6 months.

RESULTS

A cohort of 39 consecutive patients presenting between 2000 and 2020 were eligible for inclusion. Subdural empyema was the most common intracranial complication followed by extradural abscess and intraparenchymal abscess. Mean length of hospital stay was 42 days. Sixteen patients were managed with combined ENT and neurosurgical interventions, 15 patients underwent ENT procedures alone and 4 patients had only neurosurgical drainage. Four patients initially underwent non-operative management. The rates of return to the operating theatre, neurological deficits and 90-day mortality were 19, 9 and 3, respectively, and were comparable across the 4 treatment arms. In the univariate logistic regression, only the size of an intracranial abscess was found be associated with an increased likelihood of return to the operating theatre, whereas combined ENT and neurosurgical intervention did not result in improved outcomes.

CONCLUSION

Sinogenic intracranial abscesses are associated with significant morbidity and mortality. The size of an intracranial abscess has a strong association with a need for a revision surgery.

Household drug-resistant TB contact tracing in Tajikistan

BACKGROUND: Tajikistan has a high burden of rifampicin-resistant TB (RR-TB), with 2,700 new cases estimated for 2021 (28/100,000 population). TB is spread among household members through close interaction and children exposed through household contact progress to disease rapidly and frequently.METHODS: We retrospectively analysed programmatic data from household contact tracing in Dushanbe over 50 months. We calculated person-years of follow-up, contact tracing yield, number needed to screen (NNS) and number needed to test (NNT) to find one new case, and time to diagnosis.RESULTS: We screened 6,654 household contacts of 830 RR-TB index cases; 47 new RR-TB cases were detected, 43 in Year 1 and 4 in Years 2 or 3. Ten were aged <5 years; 46/47 had TB symptoms, 34/45 had chest radiographs consistent with TB, 11/35 were Xpert Ultra-positive, 29/32 were tuberculin skin test-positive and 28/47 had positive TB culture and phenotypic drug susceptibility results. The NNS to find one RR-TB case was 141.57 and the NNT was 34.49. The yields for different types of contacts were as follows: 0.7% for screened contacts, 2.9% for tested contacts, 17.0% for symptomatic contacts and 12.1% for symptomatic contacts aged below 5 years.CONCLUSION: RR-TB household contact tracing was feasible and productive in Tajikistan, a low middle-income country with an inefficient healthcare delivery system.

Detection of Twin Pregnancies using Fetal Phonocardiogram

Fetal phonocardiogram (fPCG), or the electronic recording of fetal heart sounds, is a safe and easily available signal that can be used to monitor fetal wellbeing. In the proposed work an attempt is made to identify twin pregnancies using fPCG data recorded from the fetus with 1/3rd power in octave band filtered output as features to train K-Nearest Neighbor (KNN) and support vector machine (SVM) classifiers. The SVM classifier with the quadratic kernel is able to identify singletons and twins with a positive predictive value of 100% and 79.1% respectively. The KNN classifier with k=10 neighbors is able to identify singletons and twins with a positive predictive value of 100% and 81.8% respectively.Clinical Relevance: Identifying twin pregnancies from singleton is an essential clinical protocol followed during late pregnancy as there may be complications like twin-twin transfusion syndrome, selective fetal growth restriction, and preterm labor in twin pregnancy [1], [2]. Ultrasound imaging is the most commonly used technique for twin pregnancy detection, though it is often not affordable or available in rural or low-income populations. Utilization of fPCG in such circumstances has immense clinical potential.

Molecular surveillance detects high prevalence of the neglected parasite Mansonella ozzardi in the Colombian Amazon

Mansonellosis is an undermapped insect-transmitted disease caused by filarial nematodes that are estimated to infect hundreds of millions of people globally. Despite their prevalence, there are many outstanding questions regarding the general biology and health impacts of the responsible parasites. Historical reports suggest that the Colombian Amazon is endemic for mansonellosis and may serve as an ideal location to pursue these questions in the backdrop of other endemic and emerging pathogens. We deployed molecular and classical diagnostic approaches to survey Mansonella prevalence among adults belonging to indigenous communities along the Amazon River and its tributaries near Leticia, Colombia. Deployment of a loop-mediated isothermal amplification (LAMP) assay on blood samples revealed an infection prevalence of ∼40% for Mansonella ozzardi . This assay identified significantly more infections than blood smear microscopy or LAMP assays performed using plasma, likely reflecting greater sensitivity and the ability to detect low microfilaremias or occult infections. Mansonella infection rates increased with age and were higher among males compared to females. Genomic analysis confirmed the presence of M. ozzardi that clusters closely with strains sequenced in neighboring countries. We successfully cryopreserved and revitalized M. ozzardi microfilariae, advancing the prospects of rearing infective larvae in controlled settings. These data suggest an underestimation of true mansonellosis prevalence, and we expect that these methods will help facilitate the study of mansonellosis in endemic and laboratory settings.

Primary bedaquiline resistance in Karakalpakstan, Uzbekistan

BACKGROUND: Bedaquiline (BDQ) is widely used in the treatment of rifampicin-resistant TB (RR-TB). However, resistance to BDQ is now emerging. There are no standardised regimens for BDQ-resistant TB. This study aims to share experience in managing primary BDQ-resistant TB.METHODS: We performed a retrospective study of patients treated for RR-TB in Karakalpakstan, Uzbekistan, from January 2017 to March 2022. We identified patients with resistance to BDQ with no history of BDQ exposure. We describe baseline characteristics, treatment and follow-up of these patients.RESULTS: Twelve of the 1,930 patients (0.6%) had baseline samples resistant to BDQ with no history of BDQ exposure, 75% (9/12) of whom had been previously treated for TB. Ten (83.3%) were resistant to fluoroquinolones; respectively 66% and 50% had culture conversion by Month 3 and Month 6. The interim treatment outcomes were as follows: unfavourable treatment outcomes (3/12, 25%), favourable outcomes (2/12, 17%); the remaining seven (58%) were continuing treatment.CONCLUSIONS: A large proportion of the cases had previously been treated for TB and had TB resistant to quinolone. Both patients who had not experienced culture conversion by Month 3 had an unfavourable treatment outcome. Therefore, we recommend monthly monitoring of culture status for patients on treatment regimens for BDQ resistance.

A Bin-Based Indexing for Scalable Range Join on Genomic Data

Range-join is an operation for finding overlaps in interval-form genomic data. Range-join is widely used in various genome analysis processes such as annotation, filtering and comparison of variants in whole-genome and exome analysis pipelines. The quadratic complexity of current algorithms with sheer data volume has surged the design challenges. Existing tools have limitations on algorithm efficiency, parallelism, scalability and memory consumption. This paper proposes BIndex, a novel bin-based indexing algorithm and its distributed implementation to attain high throughput range-join processing. BIndex features near-constant search complexity while the inherently parallel data structure facilitates exploitation of parallel computing architectures. Balanced partitioning of dataset further enables scalability on distributed frameworks. The implementation on Message Passing Interface shows upto 933.5x speedup in comparison to state-of-the-art tools. Parallel nature of BIndex further enables GPU-based acceleration with 3.72x speedup than CPU implementations. The add-in modules for Apache Spark provides upto 4.65x speedup than the previously best available tool. BIndex supports wide variety of input and output formats prevalent in bioinformatics community and the algorithm is easily extendable to streaming data in recent Big Data solutions. Furthermore, the index data structure is memory-efficient and consumes upto two orders-of-magnitude lesser RAM, while having no adverse effect on speedup.

Cohort profile: the ESC EURObservational Research Programme Non-ST-segment elevation myocardial infraction (NSTEMI) Registry

AIMS

The European Society of Cardiology (ESC) EURObservational Research Programme (EORP) Non-ST-segment elevation myocardial infarction (NSTEMI) Registry aims to identify international patterns in NSTEMI management in clinical practice and outcomes against the 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without ST-segment-elevation.

METHODS AND RESULTS

Consecutively hospitalised adult NSTEMI patients (n = 3620) were enrolled between 11 March 2019 and 6 March 2021, and individual patient data prospectively collected at 287 centres in 59 participating countries during a two-week enrolment period per centre. The registry collected data relating to baseline characteristics, major outcomes (in-hospital death, acute heart failure, cardiogenic shock, bleeding, stroke/transient ischaemic attack, and 30-day mortality) and guideline-recommended NSTEMI care interventions: electrocardiogram pre- or in-hospital, pre-hospitalization receipt of aspirin, echocardiography, coronary angiography, referral to cardiac rehabilitation, smoking cessation advice, dietary advice, and prescription on discharge of aspirin, P2Y12 inhibition, angiotensin converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB), beta-blocker, and statin.

CONCLUSION

The EORP NSTEMI Registry is an international, prospective registry of care and outcomes of patients treated for NSTEMI, which will provide unique insights into the contemporary management of hospitalised NSTEMI patients, compliance with ESC 2015 NSTEMI Guidelines, and identify potential barriers to optimal management of this common clinical presentation associated with significant morbidity and mortality.

Pocket CLARITY enables distortion-mitigated cardiac microstructural tissue characterization of large-scale specimens

Molecular phenotyping by imaging of intact tissues has been used to reveal 3D molecular and structural coherence in tissue samples using tissue clearing techniques. However, clearing and imaging of cardiac tissue remains challenging for large-scale (>100 mm³) specimens due to sample distortion. Thus, directly assessing tissue microstructural geometric properties confounded by distortion such as cardiac helicity has been limited. To combat sample distortion, we developed a passive CLARITY technique (Pocket CLARITY) that utilizes a permeable cotton mesh pocket to encapsulate the sample to clear large-scale cardiac swine samples with minimal tissue deformation and protein loss. Combined with light sheet auto-fluorescent and scattering microscopy, Pocket CLARITY enabled the characterization of myocardial microstructural helicity of cardiac tissue from control, heart failure, and myocardial infarction in swine. Pocket CLARITY revealed with high fidelity that transmural microstructural helicity of the heart is significantly depressed in cardiovascular disease (CVD), thereby revealing new insights at the tissue level associated with impaired cardiac function.

Synchrosqueezed Transform based Click Event Segmentation in Phonocardiogram of Mitral Valve Prolapse

Phonocardiogram (PCG) signal of the mitral valve prolapse (MVP) patients is characterized by transient audio events which include a systolic click (SC) followed by a murmur of varying intensity. Physicians detect these auscultation clues in regular auscultation before ordering expensive echocardio-graphy test. But auscultation is often error prone and even physicians with considerable experience might end up missing these clues. Therefore developing machine learning techniques to help clinicians is the need of the hour. A segmentation technique using Fourier synchrosqueezed transform (FSST) features with a long short term memory (LSTM) network is proposed in this study. An accuracy of 99.8% on MVP dataset demonstrates the potential of the proposed method in clinical diagnosis.

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

BACKGROUND

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

METHODS

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

FINDINGS

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

INTERPRETATION

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

FUNDING

British Journal of Surgery Society.

Acquired bedaquiline resistance in Karakalpakstan, Uzbekistan

BACKGROUND: The WHO recommends the use of bedaquiline (BDQ) in longer, as well as shorter, multidrug-resistant TB (MDR-TB) treatment regimens. However, resistance to this new drug is now emerging. We aimed to describe the characteristics of patients in Karakalpakstan, Uzbekistan, who were treated for MDR-TB and acquired BDQ resistance during treatment.METHODS: We performed a retrospective study of routinely collected data for patients treated for MDR-TB in Karakalpakstan between January 2015 and December 2020. We included patients on BDQ-containing regimens with baseline susceptibility to BDQ who developed BDQ resistance at any point after treatment initiation. Patients resistant to BDQ at baseline or with no confirmed susceptibility to BDQ at baseline were excluded.RESULTS: Of the 523 patients who received BDQ-containing regimens during the study period, BDQ resistance was detected in 31 patients (5.9%); 20 patients were excluded-16 with no prior confirmation of BDQ susceptibility and 4 who were resistant at baseline. Eleven patients with acquired BDQ resistance were identified. We discuss demographic variables, resistance profiles, treatment-related variables and risk factors for unfavourable outcomes for these patients.CONCLUSION: Our programmatic data demonstrated the acquisition of BDQ resistance during or subsequent to receiving a BDQ-containing regimen in a patient cohort from Uzbekistan. We highlight the need for individualised treatment regimens with optimised clinical and laboratory follow up to prevent resistance acquisition.

Time-resolved hadronic particle acceleration in the recurrent nova RS Ophiuchi

Recurrent novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to the accretion of fresh material from a binary companion. The shock generated when ejected material slams into the companion star's wind can accelerate particles. We report very-high-energy (VHE, [Formula: see text]) gamma rays from the recurrent nova RS Ophiuchi, up to a month after its 2021 outburst, observed using the High Energy Stereoscopic System. The VHE emission has a similar temporal profile to lower-energy GeV emission, indicating a common origin, with a two-day delay in peak flux. These observations constrain models of time-dependent particle energization, favoring a hadronic emission scenario over the leptonic alternative. Shocks in dense winds provide favorable environments for efficient acceleration of cosmic-rays to very high energies.

Introducing Clinical Pathology Course to Fourth Year Medical Students as a Bridge between Pre-clinical and Clinical Medical Sciences

There isn't any vertical integration of pre-clinical and clinical sciences subjects in the existing Kathmandu University MBBS curriculum. Many of the graduates are not able to correlate the clinico-pathological aspects of various diseases as a result the rational use of investigations for diagnosing various diseases is compromised. There are few published examples of implementation of pathology instruction courses during the clinical years of medical training but it is not universally practiced. This lack of exposure to pathology may lead to poor understanding of laboratory testing and the role of pathologists in patient care. To set and implement an exemplary vertical integration of pre-clinical science with clinical science. A 12 credit hours clinical pathology education course comprising clinical hematology, cytopathology and histopathology was developed. Students belonging from the ongoing fourth year MBBS course of Birat Medical College were enrolled in the course. All of the interactive lecture sessions were delivered via an e-learning interface, using the Zoom platform as the main teaching methods. Evaluation of students' achievement of learning objectives was conducted through distributing pre and post-test online multiple-choice questionnaires. Chi-square tests were used to compare the variables between pre-test and post-test questionnaire responses. Results suggested that the designed clinical pathology course is valuable. The pretest and post-test questionnaire responses revealed the positive impact regarding the importance of introducing clinical pathology courses within the clinical year of MBBS undergraduate curriculum. Response rate to the online session was 100%. The point of agreement between the pre-test and post-test questionnaire responses were highly achieved after intervention of the clinical pathology course. A statistically significant result (p < 0.05) between all of the pre-test and post-test questionnaire responses was noted. There was a strong positive recommendation for incorporating clinical laboratory medicine courses within the MBBS clinical science curriculum. The improvement observed among fourth-year MBBS students on learning the importance of clinical pathology courses was encouraging. This experience thus contributed to set and implement an exemplary vertical integration of pre-clinical science with clinical science.

ADRENAL HISTOPLASMOSIS: AN EASTERN INDIAN PERSPECTIVE

CONTEXT

The clinical presentation of histoplasmosis is varied. Due to its propensity for adrenal involvement, histoplasmosis is an important differential diagnosis in any patient presenting with adrenal mass, bilateral in particular.

OBJECTIVE

Data on clinical presentation, pattern of adrenal involvement, radiological appearance and long-term follow-up of adrenal histoplasmosis are relatively sparse; hence we looked at it.

DESIGN

This record based single-centre retrospective study was conducted in one of the tertiary care hospitals, situated in eastern India catering the Gangetic delta.

SUBJECTS AND METHODS

Data on demographic characters, presenting manifestations, biochemical & hormonal parameters and radiological appearance of confirmed adrenal histoplasmosis cases (n=9), admitted between 2015-2019 have been retrieved. The treatment outcome and condition of patients after 1-4 years of follow-up has also been discussed.

RESULTS

Four out of the nine (44.4%) patients had predisposing immunocompromised conditions in the form of diabetes and/or chronic alcoholism while rest were immunocompetent. Seven out of nine patients (77.8 %) had signs and symptoms suggestive of adrenal insufficiency, while two (22.2%) presented with only pyrexia of unknown origin. All of them had bilateral adrenal mass, though the radiologically appearances were different. All patients received anti-fungal agents with/without hydrocortisone and/or fludrocortisone. One patient died (11.1%), while majority responded favourably to treatment. Adrenocortical function did not recover completely.

CONCLUSIONS

The possibility of adrenal histoplasmosis should always be considered in patients presenting with bilateral adrenal mass, irrespective of adrenal morphology. Treatment is effective, but many of them require supplemental hydrocortisone for quite a long period, if not lifelong. Mineralocorticoid deficiency, however, is not permanent.

198 Immediate Post-Operative PDE5i Therapy Improves Early Erectile Function Outcomes after Robot-Assisted Radical Prostatectomy (RARP)

Aim

To assess whether the timing of post-operative Phosphodiesterase Inhibitor (PDE5i) therapy after Robot Assisted Radical Prostatectomy (RARP) is associated with a change in early erectile function, continence, or safety outcomes.

Method

Data was prospectively collected from a single surgeon in one tertiary centre and retrospectively evaluated. 158 patients were treated with PDE5i therapy post RARP over a two-year period.

Results

There were no significant differences in pre-operative characteristics between the therapy groups. Patients that had bilateral nerve sparing had a mean drop in Erectile Function (EF) score by 5.4 compared to 8.8 in the unilateral group. Additionally, 34.9% of bilateral nerve sparing patients returned to baseline compared to 12.1% of unilateral. Drop in EF scores and percentage return to baseline for unilateral nerve sparing was respectively 9 and 11.1% of immediate (day 1-2), 7 and 14.8% of early (day 3-14) and 9.7 and 9.5% of late (day &gt;14) therapy (p = 0.9 and p = 0.6). For bilateral nerve sparing this was respectively 3.5 and 42.9% immediate therapy, 5.5 and 35.5% early therapy and 7.3 and 25% late therapy (p = 0.017 and p = 0.045). Pad free and social continence was achieved in 54% and 37% of those receiving immediate therapy, 60% and 33% for early therapy and 26% and 54% for late therapy. There were no differences in compliance, complication, or readmission outcomes.

Conclusions

Immediate PDE5i therapy should be considered in patients following nerve sparing RARP in order to maximise functional outcomes, especially in those undergoing bilateral nerve spare.

81 VIRTUAL: Virtual Interactive Surgical Skills Classroom – An Ongoing Randomized Controlled Trial

Introduction

High costs and inaccessibility are significant barriers to face-to-face basic surgical skills (BSS) training. Virtual classrooms enable the combination of computer-based learning with interactive expert instruction. They may optimise resources and increase accessibility, facilitating larger-scale training with a similar educational benefit. We aim to evaluate the efficacy of virtual BSS classroom training compared to both non-interactive video and face-to-face teaching.

Method

72 medical students will be randomly assigned to three equal intervention groups based on year group and surgical skill confidence. Interventions will be implemented following an instructional video. Group A will practice independently, Group B will receive face-to-face training, and Group C will attend a virtual classroom. Participants will be recorded placing three interrupted sutures with hand tied knots pre- and post-intervention, and Objective Structured Assessment of Technical Skills (OSATS) will be blind marked by two experts. Change in confidence, time to completion and a granular performance score will also be measured. Each intervention’s feasibility and accessibility will be assessed.

Results

Data collection will be completed in January 2021. Significant improvement in OSATS within groups will be indicative of intervention quality. Difference in improvement between groups will determine the relative performance of the interventions.

Conclusions

To our knowledge, this will be the largest randomised control trial investigating virtual BSS classroom training. It will serve as a comprehensive appraisal of the virtual classroom’s suitability as an alternative to face-to-face training. The findings will assist the development and implementation of further resource-efficient training programs during the COVID-19 pandemic and in the future.

Malaria, COVID-19 and angiotensin-converting enzyme 2: what does the available population data say?

The etiopathogenesis of COVID-19 and its differential geographic spread suggest some populations are apparently 'less affected' through many host-related factors that involve angiotensin-converting enzyme 2 (ACE2) protein, which is also the entry receptor for SARS-CoV-2. The role of ACE2 has been well studied in COVID-19 but not in the context of malaria and COVID-19. We have previously suggested how malaria might intersect with COVID-19 through ACE2 mutation and here we evaluate the currently available data that could provide a link between the two diseases. Based on the existing global and Indian data on malaria, COVID-19 and the suggested ACE2 mutation, the association could not be examined robustly, neither accepting nor refuting the suggested hypothesis. We strongly recommend targeted evaluation of this hypothesis through carefully designed robust molecular epidemiological studies.

O43 Virtual: virtual interactive surgical skills classroom: a randomized controlled trial (protocol)

Introduction

High costs and inaccessibility are significant barriers to face-to-face basic surgical skills (BSS) training. Virtual classrooms enable the combination of computer-based learning with interactive expert instruction. They may optimise resources and increase accessibility, facilitating larger-scale training with a similar educational benefit. We aim to evaluate the efficacy of virtual BSS classroom training compared to both non-interactive video and face-to-face teaching.

Method

72 medical students will be randomly assigned to three equal intervention groups based on surgical skills experience and confidence. Interventions will be implemented following an instructional video. Group A will practice independently, Group B will receive face-to-face training, and Group C will attend a virtual classroom. Participants will be recorded placing three interrupted sutures with hand tied knots pre- and post-intervention. Objective Structured Assessment of Technical Skills (OSATS) will be blind marked by two experts.

Result

Change in confidence, time to completion and a novel granular performance score will also be measured. Each intervention’s feasibility and accessibility will be assessed. Significant improvement in OSATS within groups will be indicative of intervention quality. Difference in improvement between groups will determine the relative performance of the interventions.

Conclusion

This will be the largest randomised control trial investigating virtual BSS classroom training. It will serve as a comprehensive appraisal of the suitability of virtual classrooms as an alternative to face-to-face training. The findings will assist the development and implementation of further resource-efficient training programs during the COVID-19 pandemic and beyond.

Take-home Message

This is the first RCT assessing virtual basic surgical skill classroom training and serves as a comprehensive appraisal of the suitability of virtual classrooms as an alternative to face-to-face training. The findings will assist the development and implementation of further resource-efficient training programs during the COVID-19 pandemic and in the future.

Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow

Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.

The significance of urgent ultrasound scan for shoulder dislocation in patients above the age of 40: A prospective British Elbow and Shoulder Society pathway implementation study

BACKGROUND

The highlight of the British Elbow and Shoulder Society pathway for the management of traumatic anterior shoulder instability is early imaging in patients aged over 40 years to assess rotator cuff integrity and early repair, if indicated to optimise function. The senior author set up a protocol in our institute to streamline the diagnostic process for this cohort of patients. This was a retrospective analysis from a prospectively collected database to highlight the importance of early specialist imaging.

METHODS

Our protocol is to perform urgent ultrasound scans for all suitable patients above 40 years after first-time traumatic shoulder dislocation. Demographics, associated injuries, ultrasound scan results, operations and functional outcomes were collated.

RESULTS

One year following the introduction of our protocol, 40 patients with a mean age of 67 (range, 42-89; SD = 13.1) had ultrasound. The incidence of full-thickness rotator cuff tears was 57.5% (n = 23). Eleven patients with confirmed full-thickness rotator cuff tears underwent surgery. The mean age of surgical patients was significantly younger than the non-surgical group (p = 0.004).

DISCUSSION

The use of early diagnostic imaging demonstrated a high incidence of full-thickness rotator cuff tears in this cohort of patients. This allowed early surgical repair to optimise function.

31 Immediate Post-Operative Phosphodiesterase-5 Inhibitors (PDE5i) Therapy Improves Early Erectile Function Outcomes After Robot Assisted Radical Prostatectomy (RARP)

Introduction

To assess whether the timing of post-RARP PDE5i therapy affects early erectile function, continence, or safety outcomes.

Method

Data from 158 patients treated with PDE5is post-RARP was prospectively collected over two years from a single surgeon at one tertiary centre and retrospectively evaluated. Therapy was started: immediately (day 1-2) in 29%, early (day 3-14) in 37% and late (after day 14) post-op in 34%. EPIC-26 Erectile Function (EF) scores were collected pre-op and post-op after a median 43-day follow-up interval.

Results

Drop in EF scores and percentage return to baseline post unilateral nerve sparing (UNS) compared to bilateral nerve sparing (BNS) RARP was respectively 9 and 11.1% versus 3.5 and 42.9% of immediate therapy, 7 and 14.8% versus 5.5 and 35.5% of early and 9.7 and 9.5% versus 7.3 and 25% of late. Pad free and social continence was achieved in 54% and 37% of those receiving immediate therapy, 60% and 33% for early and 26% and 54% for late.

Conclusions

Immediate post RARP PDE5i therapy may protect EF and should be considered clinically, with more benefits for BNS than UNS patients. Immediate or early, rather than late, PDE5i therapy improved early continence in BNS patients.

Consensus statement from the international consensus meeting on post-traumatic cranioplasty

Background

Due to the lack of high-quality evidence which has hindered the development of evidence-based guidelines, there is a need to provide general guidance on cranioplasty (CP) following traumatic brain injury (TBI), as well as identify areas of ongoing uncertainty via a consensus-based approach.

Methods

The international consensus meeting on post-traumatic CP was held during the International Conference on Recent Advances in Neurotraumatology (ICRAN), in Naples, Italy, in June 2018. This meeting was endorsed by the Neurotrauma Committee of the World Federation of Neurosurgical Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and several other neurotrauma organizations. Discussions and voting were organized around 5 pre-specified themes: (1) indications and technique, (2) materials, (3) timing, (4) hydrocephalus, and (5) paediatric CP.

Results

The participants discussed published evidence on each topic and proposed consensus statements, which were subject to ratification using anonymous real-time voting. Statements required an agreement threshold of more than 70% for inclusion in the final recommendations.

Conclusions

This document is the first set of practical consensus-based clinical recommendations on post-traumatic CP, focusing on timing, materials, complications, and surgical procedures. Future research directions are also presented.

Integrated ozonation assisted electrocoagulation process for the removal of cyanide from steel industry wastewater

This work focuses on the removal of cyanide, chemical oxygen demand (COD), biological oxygen demand (BOD), and chloride from biological oxidation treated (BOT) effluent of the steel industry by integrated ozonation assisted electrocoagulation method. The removal efficiency of the pollutants was found to be inefficient when the electrocoagulation or ozonation process was performed separately. However, a combination of ozonation and electrocoagulation gives a highly satisfactory result. Such an integrated approach for the treatment of BOT effluent has not been previously investigated. The effects of operating variables viz. ozone generation rate, current density, and analysis time on pollutant removal were primarily analyzed for the hybrid process. The experimental operating condition was optimized and was seen that ozone generation rate of 1.33 mg s^-1, ozonation time of 40 min, a current density of 100 A m^-2, and electrolysis time of 30 min were sufficient for reducing the pollutant concentration below its permissible limits. The removal efficiencies of the combined process at optimum conditions were 99.8%, 94.7%, 95%, and 46.5% for cyanide, COD, BOD, and chloride ions, respectively. A kinetic study was performed for the degradation of the pollutants during ozonation. The pseudo-first-order kinetic model was found to be best suited for the analysis with the highest R² value of 0.99 for cyanide, COD, BOD, and chloride, respectively. The mass transfer study conducted further showed that the volumetric mass transfer coefficient, K_la, was increased with that of the ozone generation rate. Cost estimation of the hybrid process was done and compared with that of the other reported integrated process.

Assessing continuum of trauma care for road accident victim in Jodhpur, Rajasthan

Background

Road traffic injuries (RTIs) are a major public health problem, requiring concerted efforts both for their prevention and a reduction of their consequences. The present study was designed to assess the existing process of pre-hospital trauma care administered to road accident victims in a fast urbanizing city of Jodhpur, Rajasthan

Methods

A cross-sectional study was designed from 1st November 2018 to 30th June 2019. All cases who were admitted to tertiary level trauma care facility in the study period were reviewed and were analyzed for type of injuries suffered, prehospital care services availed and the time duration that elapsed before patient arrived at tertiary health facility. Geographic information system was used to identify clustering of accident hot spots in the Jodhpur district.

Results

A total of 137 patients or their caregivers were interviewed during the study period. A large proportion of patients 57(41.6%) were unconscious in post-crash phase. Private taxis contributed to maximum patient transfer (75.9%) and only 12.4% were transported through ambulance. Almost three fourth (78.1%) of patients received some form of pre-hospital care within 30 minutes of accident. About one third patients (35.7%) reached the trauma facility directly after the accident while majority (64.9%) were referred from other health facilities

Conclusions

Pre-hospital trauma care for road traffic accident victims is available in golden hour for majority of victims in Jodhpur district. Victims from rural area and tourists form a sizeable proportion of accident victims brought to trauma care facility. The primary health care facilities play a pivotal role in managing victims as first point of care. Future research is thus warranted to explicitly examine the role of health professionals at primary health care facilities in administering pre-hospital trauma care.

Key messages

The primary health care facilities play a pivotal role in managing victims as first point of care. In areas with evolving trauma systems, pre-hospital trauma care strengthening requires capacity building of all level of health professionals.

Safety and efficacy of laparoscopic near-total colectomy and ileo-distal sigmoid anastomosis as a modification of total colectomy and ileorectal anastomosis for prophylactic surgery in patients with adenomatous polyposis syndromes: a comparative study

AIM

Colectomy in patients with adenomatous polyposis (AP) syndromes demands good oncological and surgical outcome. Total colectomy with ileorectal anastomosis (TC-IRA) is one surgical option for these patients. Anastomotic leakage rates of 11% have been reported following TC-IRA. Ileo-distal sigmoid anastomosis (IDSA) is a recent modification of our practice. Our aim was to compare postoperative outcome in patients with AP following near-total colectomy with IDSA (NT-IDSA) and TC-IRA at a single institution.

METHOD

A prospectively maintained database was reviewed to identify patients with AP who underwent laparoscopic NT-IDSA and TC-IRA. Patient demographics, early morbidity and mortality and outcome of endoscopic surveillance were evaluated.

RESULTS

A total of 191 patients with AP underwent laparoscopic colectomy between 2006 and 2017, of whom 139 (72.8%) underwent TC-IRA and 52 (27.2%) NT-IDSA. The median age at surgery in the TC-IRA and NT-IDSA groups was 20 years (IQR 17-45) and 27 years (IQR 19-50), respectively. Grade II complications were comparable between the two groups. There were no anastomotic leakages in the NT-IDSA group compared with 15 (10.8%) in the TC-IRA group (P = 0.0125) and no reoperation in the NT-IDSA group compared with 17 (12.2%) in the TC-IRA group (P = 0.008). The frequency of polypectomies per flexible sigmoidoscopy was comparable between the two groups.

CONCLUSION

This study demonstrates that laparoscopic NT-IDSA for polyposis is associated with a significant improvement in anastomotic leakage rates and surgical outcome. It is too soon to tell whether NT-IDSA alters the need for further intervention, either endoscopic polypectomy or further surgery.

Utilization of LD slag from steel industry for the preparation of MF membrane

This work is focused on utilizing the solid waste generated from steel industry for the fabrication of porous ceramic membrane from Linz Donawitz (LD) slag. Membranes were fabricated using uniaxial method sintered at three different temperatures like 650 °C, 850 °C and 950 °C. Membranes fabricated with raw LD slag gave a highly basic filtrate. In contrast with this issue, LD slag was modified using acetic acid and CO₂ purging to convert calcium oxide which is present in the slag to calcium carbonate. The membranes fabricated from modified LD slag showed a filtrate pH of 8.4 and 8.5. Porosity, pore size distribution, flexural strength, chemical stability was determined and pure water flux experiments were conducted to evaluate the efficiency of the prepared membranes. Considering the raw materials cost, the cost of the fabricated membranes was estimated in the range of 32.55-55.7 USD/m². This work gives a potential path to develop microfiltration ceramic membrane with, high porosity and great quality in terms of strength and chemical stability. The fabricated membranes were utilized in a hybrid technique (flocculation followed by microfiltration) for the treatment of cold roll mill (CRM) wastewater generated from steel industry. Use of LD slag for the fabrication of ceramic membrane is not only an appealing option towards the commercialization of membrane, yet also great option to reduce the solid waste which is dumped to the environment.

Obesity in acute alcoholic hepatitis increases morbidity and mortality

BACKGROUND

Alcohol and obesity synergise to increase the risk of liver-related mortality. We examined the influence of adiposity on clinical outcomes in alcoholic hepatitis (AH) and the underlying inflammatory crosstalk between adipose tissue (AT) and the liver.

METHODS

A cohort of 233 patients with AH from the UK and USA provided data to analyse the effects of obesity in AH. Body mass index was corrected for the severity of ascites, termed cBMI. Inflammatory and metabolic profiling was undertaken by proteome analysis of human serum samples. The effect of alcohol on adipose tissue and CXCL11 expression was studied in 3 T3-derived adipocytes and in mice using the high-fat diet-plus-binge ethanol model.

FINDINGS

Obesity was common amongst patients with AH, seen in 19% of individuals. Obesity (HR 2.22, 95%CI 1.1-4.3, p = .022) and underweight (HR 2.38, 1.00-5.6, p = .049) were independently associated with mortality at 3 months. Proteome analysis demonstrated multiple metabolic and inflammatory factors differentially expressed in obese AH verse lean AH, with CXCL11 being the most elevated factor in obese AH. In vitro analysis of cultured adipocytes and in vivo analysis of mouse models showed that alcohol induced CXCL11 expression in AT, but not in liver.

INTERPRETATION

Obesity is common in AH and associated with a greater than two-fold increase in short-term mortality. Obese AH is associated with a different inflammatory phenotype, with the greatest elevation in CXCL11. These data confirm that adiposity is clinically important in acute alcohol-related liver disease and illustrate the adipose-liver inflammatory axis in AH. FUND: This work was supported in part by an EASL Sheila Sherlock Physician Scientist Fellowship. The funder played no role in gathering or analysing data or writing the manuscript. This paper presents independent research supported by the NIHR Birmingham Biomedical Research Centre at the University Hospitals Birmingham NHS Foundation Trust and the University of Birmingham. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

Evaluation of Electron Specific Absorbed Fractions in Organs of Digimouse Voxel Phantom Using Monte Carlo Simulation Code FLUKA

BACKGROUND

For preclinical evaluations of radiopharmaceuticals, most studies are carried out on mice. Electron specific absorbed fractions (SAF) values have had vital role in the assessment of absorbed dose. In past studies, electron SAFs were given for limited source target pairs using older reports of human organ compositions.

OBJECTIVE

Electron specific absorbed fraction values for monoenergetic electrons of energies 15, 50, 100, 500, 1000 & 4000 keV were evaluated for the Digimouse voxel phantom incorporated in Monte Carlo code FLUKA. From the latest report (International Commission on Radiological Protection ICRP) 110, organ compositions and densities were adopted.

MATERIAL AND METHODS

We have used the Digimouse voxel phantom which was incorporated in Monte Carlo code FLUKA. Simulation studies were performed using FLUKA. The organ sources considered in this study were lungs, skeleton, heart, bladder, testis, stomach, spleen, pancreas, liver, kidney, adrenal, eye and brain. The considered target organs were lungs, skeleton, heart, bladder, testis, stomach, spleen, pancreas, liver, kidney, adrenal and brain. Eye and brain were considered as target organs only for eye and brain as source organs.

RESULTS

The electron SAF values for self-irradiation decreases with increasing electron energy. The electron SAF values for cross-irradiation are also found to be dependent on the electron energy and the geometries of source and target. Organ masses and electron SAF values are presented in tabular form.

CONCLUSION

The results of this study will be useful in evaluating the absorbed dose to various organs of mice similar in size to the present study.

FP2-3 Ten years of paediatric neuro-oncology surgery: quantifying and predicting complications after surgery for intracranial tumour excision

Objectives

To measure complications of paediatric neurooncology surgery using the Clavien Dindo grading scale, and identify predictors of surgical morbidity.

Design

Retrospective review of prospectively collected data.

Subjects

All paediatric patients treated with craniotomy for excision of intracranial tumour between 2008 and 2017 in a single tertiary paediatric neurosurgery centre.

Methods

Demographics, surgical details and perioperative complications were prospectively recorded between 0 and 30 days post operatively. These were retrospectively graded using the CD scale. Data analysis was done in R using logistic regression. Significance was defined as p<0.05

Results

Between 3/1/2008 and 21/12/2017 there were 322 operations, on 254 patients (142 Male). Median age at surgery was 9 years (IQR 4–13 years). 48% were without complication on the CD scale. Maximum CD grade complication for each procedure was 1 in 11%, 2 in 19%, 3A in 2%, 3B in 14%, and 4 in 0.6% of operations. 30 day mortality was 0.9%. CD grade of 3B or over was associated with infratentorial tumours (OR 2.24; CI 1.10–4.68; p=0.004) and WHO grade III tumours (OR 4.12; CI 1.56–10.86; p=0.028).

Conclusions

Complications in paediatric neurooncology surgery are common overall, but our results are favourable in comparison to the literature. The CD scale has limitations in neurosurgery but gives insight into the health economic impact of complications. Infratentorial tumours, and WHO grade III tumours were associated with increased morbidity.

P96 Screening for cerebrovascular pathology on the basis of positive family history in the paediatric population

Objectives

Neurovascular disorders are uncommon, complex conditions in children. We reviewed the screening practice and outcome of children referred to the neurovascular service on the basis of positive family history.

Design

Retrospective review of prospectively maintained database.

Subjects

Children referred to the neurovascular service on the basis of family history, for screening at our hospital.

Methods

We retrospectively examined our database between July 2008 and April 2018 for the reasons for referral, family history, investigations performed, and the outcome of the screening process.

Results

44 children were reviewed (23 male, median age 10). Thirty-one children had an MRI/MRA brain. One child subsequently had uncomplicated digital subtraction angiography. Thirty children were referred due to a family history of subarachnoid haemorrhage, of which 17 had a single first-degree relative, and two had two first-degree relatives. Nine children were referred with a family history of arteriovenous malformation, (2 were associated with hereditary haemorrhagic telangiectasia). Five children were discussed due to a family history of non-specific haemorrhagic stroke. Seven children had a history of headache, (4 were prescribed Pizotifen for migraine). No neurovascular pathology was detected following screening within our cohort.

Conclusions

A consensus screening policy does not exist but is required both to guide clinical practice and to assuage parental or patient concerns. We will survey UK paediatric centres to commence this process.

Abstract P3-03-11: Intraoperative assessment of the sentinel node in breast cancer by one step nucleic acid assay: Experience of over 1100 patients

Introduction

The intraoperative assessment of the sentinel node in women with breast cancer enables an immediate axillary node clearance to be done as part of the same operative procedure if the sentinel node is positive. This has significant benefits for the Patient, the Surgeon and the Health Care Provider. There are a variety of methods for the intra-operative assessment of the sentinel node which include: Touch Imprint Cytology, Frozen Section Analysis and Polymerase Chain Reaction (PCR) based molecular assays. OSNA is an automated molecular assay using a Polymerase Chain Reaction (PCR), which detects the presence of cytokeratin 19 in the sentinel node. We report our experience of OSNA for the intraoperative assessment of the sentinel node in our institution with 1148 patients.

Methods

All patients with operable breast cancer who were found to be node negative on clinical and radiological assessment of the axilla, and who had their axilla staged by a sentinel node biopsy at the Breast Unit at Warwick Hospital, UK over a 7 year period were included in this study. Data was collected from a prospective database maintained at the Breast Unit. The axillary node positivity rate and the number of patients with macrometastatic and micrometastatic disease as detected by OSNA was collected and compared with a group of 411 patients who had the intraoperative assessment by Touch Imprint Cytology and final histology by conventional Haematoxylin & Eosin (H&E) assessment, prior to the introduction of OSNA. The Chi-square test were used for statistical significance.

Results

1148 patients had their sentinel node assessed intraoperatively using OSNA in this 7 year study period. The sentinel node was positive in 376 patients (32.8%). Of those who had a positive node, 183 (15.9%) had macro-metastatic disease and 193 (16.8%) had micro-metastatic disease. When compared to 411 patients in the pre-OSNA period, that were assessed by Touch Imprint Cytology and H&E sections, the node positivity rate increased from 23.8% to 32.8% (p&lt;0.05) with the introduction of OSNA. Whilst there was no significant increase in the rate of macrometastatic disease – 20.4% versus 15.9 % ( p0.038), there was a significant increase in the patients who had micrometastases detected on OSNA - 3.4% versus 16.8 % ( p&lt;0.05) as shown in the table.

Conclusion

Our results demonstrate that OSNA is a more sensitive test for picking up metastatic disease, especially micrometastatic disease, in the sentinel node. Whilst this did cause some anxiety initially, the results of recent trials like ACSOG Z-11 and IBCSG 23-01 have shown that small volume disease or micrometastases in the sentinel node do not require an axillary node clearance. Intraoperative assessment of the sentinel node with OSNA significantly upstages the axillary nodal status, especially with regard to micrometastatic disease, but the ability to proceed to an axillary node clearance at the same operation as the sentinel node biopsy, still has significant advantages for the Patient, Surgeon and Health Care Providers.

Citation Format: Clarke D, Sinha A, Ion L, Weston S, Jones L, Kham M, Harries S. Intraoperative assessment of the sentinel node in breast cancer by one step nucleic acid assay: Experience of over 1100 patients [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 P3-03-11.

Proteasome lid bridges mitochondrial stress with Cdc53/Cullin1 NEDDylation status

Cycles of Cdc53/Cullin1 rubylation (a.k.a NEDDylation) protect ubiquitin-E3 SCF (Skp1-Cullin1-F-box protein) complexes from self-destruction and play an important role in mediating the ubiquitination of key protein substrates involved in cell cycle progression, development, and survival. Cul1 rubylation is balanced by the COP9 signalosome (CSN), a multi-subunit derubylase that shows 1:1 paralogy to the 26S proteasome lid. The turnover of SCF substrates and their relevance to various diseases is well studied, yet, the extent by which environmental perturbations influence Cul1 rubylation/derubylation cycles per se is still unclear. In this study, we show that the level of cellular oxidation serves as a molecular switch, determining Cullin1 rubylation/derubylation ratio. We describe a mutant of the proteasome lid subunit, Rpn11 that exhibits accumulated levels of Cullin1-Rub1 conjugates, a characteristic phenotype of csn mutants. By dissecting between distinct phenotypes of rpn11 mutants, proteasome and mitochondria dysfunction, we were able to recognize the high reactive oxygen species (ROS) production during the transition of cells into mitochondrial respiration, as a checkpoint of Cullin1 rubylation in a reversible manner. Thus, the study adds the rubylation cascade to the list of cellular pathways regulated by redox homeostasis.

Digital biomarkers of spine and musculoskeletal disease from accelerometers: Defining phenotypes of free-living physical activity in knee osteoarthritis and lumbar spinal stenosis

BACKGROUND CONTEXT

Lumbar spinal stenosis (LSS) and knee osteoarthritis (OA) are 2 of the leading causes of disability worldwide. In order to provide disease-specific prescriptions for physical activity, there is a clear need to better understand physical activity in daily life (performance) in these populations.

PURPOSE

To discover performance phenotypes for LSS and OA by applying novel analytical methods to accelerometry data. Specific objectives include the following: (1) to identify characteristic features (phenotypes) of free-living physical activity unique to individuals with LSS and OA, and (2) to determine which features can best differentiate between these conditions.

STUDY DESIGN AND SETTING

Leveraging data from 3 existing cross-sectional cohorts, accelerometry signal feature characterization and selection were performed in a computational laboratory.

PATIENT SAMPLE

Data from a total of 4,028 individuals were analyzed from the following 3 datasets: LSS Accelerometry Database (n=75); OA Initiative (n=1950); and the 2003 to 2004 National Health and Nutrition Examination Survey (pain-free controls, n=2003).

METHODS

In order to characterize the accelerometry signals, data were examined using (1) standard intervals for counts/minute from Freedson et al. and (2) the physical performance intervals for mobility-limited pain populations. From this, 42 novel accelerometry features were defined and evaluated for significance in discriminating between the groups (LSS, OA, and controls) in order to then determine which sparse set of features best differentiates between the groups. These sparse sets of features defined the performance phenotypes.

OUTCOME MEASURES

Accelerometry features and their ability to differentiate between individuals with LSS, OA, and controls.

RESULTS

Given age and gender, classification rates were at least 80% accurate (pairwise) between diseased and pain-free populations (LSS vs. controls and OA vs. controls). The most important features to distinguish between disease groups corresponded to measures in the light and sedentary activity intervals. The more subtle classification between diseased populations (LSS vs. OA) was 72% accurate, with light and moderate activity providing the prominent distinguishing features.

CONCLUSIONS

We describe the discovery of performance phenotypes of LSS and OA from accelerometry data, revealed through a novel set of features that characterize daily patterns of movement in people with LSS and OA. These performance phenotypes provide a new method for analyzing free-living physical activity (performance) in LSS and OA, and provide the groundwork for more personalized approaches to measuring and improving function.