REFORMS: Consensus-based Recommendations for Machine-learning-based Science

Machine learning (ML) methods are proliferating in scientific research. However, the adoption of these methods has been accompanied by failures of validity, reproducibility, and generalizability. These failures can hinder scientific progress, lead to false consensus around invalid claims, and undermine the credibility of ML-based science. ML methods are often applied and fail in similar ways across disciplines. Motivated by this observation, our goal is to provide clear recommendations for conducting and reporting ML-based science. Drawing from an extensive review of past literature, we present the REFORMS checklist (recommendations for machine-learning-based science). It consists of 32 questions and a paired set of guidelines. REFORMS was developed on the basis of a consensus of 19 researchers across computer science, data science, mathematics, social sciences, and biomedical sciences. REFORMS can serve as a resource for researchers when designing and implementing a study, for referees when reviewing papers, and for journals when enforcing standards for transparency and reproducibility.

Leakage and the reproducibility crisis in machine-learning-based science

Machine-learning (ML) methods have gained prominence in the quantitative sciences. However, there are many known methodological pitfalls, including data leakage, in ML-based science. We systematically investigate reproducibility issues in ML-based science. Through a survey of literature in fields that have adopted ML methods, we find 17 fields where leakage has been found, collectively affecting 294 papers and, in some cases, leading to wildly overoptimistic conclusions. Based on our survey, we introduce a detailed taxonomy of eight types of leakage, ranging from textbook errors to open research problems. We propose that researchers test for each type of leakage by filling out model info sheets, which we introduce. Finally, we conduct a reproducibility study of civil war prediction, where complex ML models are believed to vastly outperform traditional statistical models such as logistic regression (LR). When the errors are corrected, complex ML models do not perform substantively better than decades-old LR models.

Southern ocean carbon and heat impact on climate

The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal timescales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea-ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

Broad responses and attitudes to having music in surgery (the BRAHMS study) - a South African perspective

BACKGROUND

Music is played in operating theatres (OTs) throughout the world, though controversy around its use exists. While some clinicians may find background music favourable to the theatre mood and a way to augment surgical performance, there is concern raised over its distracting and noise-creating properties.

METHODS

In this prospective observational study, between August and December 2021, 110 surgeons and registrars in South Africa responded to a survey investigating the way they use music, and their perceptions and attitudes towards its effect on the OT environment.

RESULTS

In this cohort, 66% were male, 29% were consultants and the most common age range was 30-39 years old. Eighty per cent of respondents reported that music was played at least "sometimes", with 74% reporting that they enjoyed it. Easy Listening was the most played and preferred genre followed by Top 40/Billboard hits. Overwhelmingly, respondents reported that background music in the OT improved temperament, focus, mood, and performance, though over a quarter felt it worsened communication. Thirty-one per cent of respondents reported that the choice of music depended on the type of operation, and 70% would turn music down or off during crises. Those who enjoyed music in their spare time were significantly more likely to enjoy music in the OT and perceive it positively.

CONCLUSION

This study provides a window into the surgeons' use of and attitudes to intraoperative music in South Africa. While overall, music is viewed positively by this cohort, some concerns remain regarding communication and distractedness. Further interventional and qualitative studies would be useful.

Are immediate postoperative X-Rays valuable in evaluating complications of primary total hip arthroplasty?

PURPOSE

This study aimed to investigate the complications of primary total hip arthroplasty based on immediate postoperative X-rays. The overall quality and cost of X-rays were assessed.

METHODS

The institutional database was queried to identify all patients who underwent total hip arthroplasty in a single institution between January 1, 2018, and December 31, 2018. Immediate postoperative X-rays were reviewed to identify the complications such as periprosthetic fractures, dislocation, and fixation failure. The quality and cost of X-ray were assessed. The complications were categorized as "known" and "unknown" according to the intraoperative fluoroscopic results.

RESULTS

A total of 518 total hip arthroplasties were included in this study. Based on intraoperative fluoroscopy, periprosthetic fractures were found in 10 (2%) THAs. Compared to the X-rays taken immediately after surgery, 9 periprosthetic fractures (recorded as "known") were found and 1 was not (recorded as "unknown"). There was no significant difference between intraoperative fluoroscopy and X-rays (P > 0.05). Of the 518 X-rays, 225 (43%) were of suboptimal quality. The cost of a single portable pelvic X-ray was $647.

CONCLUSION

In total hip arthroplasty, X-rays taken immediately after surgery rarely reveal unknown complications. The X-rays are often of suboptimal quality, have minimal clinical utility, and are less cost-effective.

1515 A Survey on The Perceived Effect of Background Music on Intra-Operative Stress, Anxiety and Surgical Task Load On the Operating Surgeon

Introduction

Music is commonly played in operating theatres throughout the world though its use remains controversial. There is growing literature supporting the notion that playing background music can improve a surgeon’s task performance and reduce performance stress. We present findings from our survey of surgeons about their perceptions of the effect of intra-operative music on their stress levels.

Method

Surgeons and registrars from three different specialties – general, vascular, and paediatric surgery – in a single tertiary centre were surveyed on their views on the effect of music in theatre. Two instruments were used to assess parameters of stress: the modified 6-point state trait anxiety inventory (STAI-6) and the surgical task load index (SURG-TLX).

Results

There were 35 respondents across the three surgical specialties (78% response rate). Pop and “easy listening” were the most popular genres. A majority felt music improved their temperament (75%) and perceived stress (63%). 59% of respondents reported no to low perceived anxiety with music, compared with 31% reporting moderate and 9% high anxiety based on STAI-6 parameters. Regarding SURG-TLX parameters and music, respondents overall perceived feeling less anxious, rushed and mentally fatigued though more distracted.

Conclusions

Music is generally thought to have positive subjective effects on the theatre environment with regards to anxiety levels, temperament, perceived stress, and parameters within the surgical task load index. This is counterbalanced by a smaller group of respondents who felt that music can impair communication and increase distraction within theatre. Music used appropriately may reduce perceptions of stress in theatre.

A split-tattoo randomized Q-switched neodymium-doped yttrium-aluminium-garnet laser trial comparing the efficacy of a novel three-pass, one-session method with a conventional method in the treatment of blue/black tattoos in darker skin types

Tattoos with blue/black ink show good lightening of pigment after treatment with 1064 nm Q-switched (QS) neodymium-doped yttrium-aluminium-garnet (Nd:YAG) laser. In this randomized trial, we compared the efficacy of a novel three pass, one session procedure (R15 method) with a conventional method for treating blue/black tattoos in darker skin types. Tattoos were treated with 1064 nm QS Nd:YAG Laser with a spot size of 4 mm, fluence of 5 J/cm² and frequency of 5 Hz. The tattoo pigment lightening was comparable with both methods. Thread-like tattoos had significantly better pigment lightening with fewer side effects than the broad band-like tattoos. We would like to recommend the R15 method of the QS Nd:YAG laser for thread-like tattoos, which can save patients' time, cut short the frequency of their hospital visits and, more importantly, decrease the cost involved in it.

504 Can Measuring Heart Rate Variability in The Operating Surgeon Provide Insight into Intra-Operative Stress? A Literature Review and Direction for Research

Introduction

Stress affects the internal environment of the operating surgeon. Examining ways to mitigate this could prove important to the health of both surgeon, and patients.

Heart rate variability (HRV) is emerging as a novel, validated measure of autonomic nervous system (ANS) function with developing accessible and non-invasive technologies. HRV parameters correlate to ANS function and can be used to measure responses to various stimuli.

Method

A search strategy was developed to identify 23 articles that matched inclusion criteria. These included data collected intra-operatively with ambulatory monitoring, in simulated settings and one systematic review.

Results

Several studies found increased sympathetic response in the operating surgeon – which correlates with subjective reporting of stress. Some studies compared variables; one study suggested that laparoscopic colorectal surgery caused higher mental strain than open, while another suggested higher stress in surgeons while teaching compared to when primary operator. There have been no comparative trials using HRV in surgeons.

Conclusions

We present a review of the growing literature regarding HRV measurement in surgeons. This novel tool is a promising avenue to provide psychophysiological insight into the operating surgeon. This could guide future research into optimising the theatre environment for intra-operative performance using controlled or in-situ design.

Measuring the predictability of life outcomes with a scientific mass collaboration

How predictable are life trajectories? We investigated this question with a scientific mass collaboration using the common task method; 160 teams built predictive models for six life outcomes using data from the Fragile Families and Child Wellbeing Study, a high-quality birth cohort study. Despite using a rich dataset and applying machine-learning methods optimized for prediction, the best predictions were not very accurate and were only slightly better than those from a simple benchmark model. Within each outcome, prediction error was strongly associated with the family being predicted and weakly associated with the technique used to generate the prediction. Overall, these results suggest practical limits to the predictability of life outcomes in some settings and illustrate the value of mass collaborations in the social sciences.

Making content caching policies 'smart' using the deepcache framework

In this paper, we present Deepcache a novel Framework for content caching, which can significantly boost cache performance. Our Framework is based on powerful deep recurrent neural network models. It comprises of two main components: i) Object Characteristics Predictor, which builds upon deep LSTM Encoder-Decoder model to predict the future characteristics of an object (such as object popularity) - to the best of our knowledge, we are the first to propose LSTM Encoder-Decoder model for content caching; ii) a caching policy component, which accounts for predicted information of objects to make smart caching decisions. In our thorough experiments, we show that applying Deepcache Framework to existing cache policies, such as LRU and k-LRU, significantly boosts the number of cache hits.

Privacy, Ethics, and Data Access: A Case Study of the Fragile Families Challenge

Stewards of social data face a fundamental tension. On one hand, they want to make their data accessible to as many researchers as possible to facilitate new discoveries. At the same time, they want to restrict access to their data as much as possible to protect the people represented in the data. In this article, we provide a case study addressing this common tension in an uncommon setting: the Fragile Families Challenge, a scientific mass collaboration designed to yield insights that could improve the lives of disadvantaged children in the United States. We describe our process of threat modeling, threat mitigation, and third-party guidance. We also describe the ethical principles that formed the basis of our process. We are open about our process and the trade-offs we made in the hope that others can improve on what we have done.

Web-Based Perceived Present Control Intervention for Voice Disorders: A Pilot Study

OBJECTIVE

Voice disorders are common and negatively affect various life domains such as occupational functioning and emotional well-being. Perceived present control, a factor that is amenable to change, may reduce the effect of voice disorders on these outcomes. This pilot study aimed to (1) establish the feasibility, usability, and acceptability of a web-based perceived present control intervention for individuals with voice disorders and (2) gather preliminary data on the effectiveness of the intervention. This study is the first to assess whether a web-based psychological intervention would decrease self-reported voice handicap in this population.

METHODS

Participants (N = 20) were recruited from an otolaryngology clinic at a large, Midwest university and the surrounding urban community, and completed a 3-week web-based intervention that incorporated psychoeducation and written exercises on increasing perceived present control.

RESULTS

Supporting feasibility, the intervention components had high completion rates (75%-95%). Most participants planned to continue the perceived control exercises after study completion and would recommend the intervention to others, demonstrating usability and acceptability. There was a significant decrease in self-reported voice handicap (Voice Handicap Index-10) from pretest (M = 18.38, standard deviation = 4.41) to post-test (M = 15.22, standard deviation = 4.55) with a large effect size (within-group d = -0.86, P < 0.05).

CONCLUSIONS

Focusing on perceived present control as a teachable skill may be a useful addition to voice disorder treatment armamentarium. Future studies will incorporate a comparison group and larger sample sizes to assess further the role of perceived present control interventions in voice care.

When the cookie meets the blockchain: Privacy risks of web payments via cryptocurrencies

We show how third-party web trackers can deanonymize users of cryptocurrencies. We present two distinct but complementary attacks. On most shopping websites, third party trackers receive information about user purchases for purposes of advertising and analytics. We show that, if the user pays using a cryptocurrency, trackers typically possess enough information about the purchase to uniquely identify the transaction on the blockchain, link it to the user’s cookie, and further to the user’s real identity. Our second attack shows that if the tracker is able to link two purchases of the same user to the blockchain in this manner, it can identify the user’s cluster of addresses and transactions on the blockchain, even if the user employs blockchain anonymity techniques such as CoinJoin. The attacks are passive and hence can be retroactively applied to past purchases. We discuss several mitigations, but none are perfect.

I never signed up for this! Privacy implications of email tracking

We show that the simple act of viewing emails contains privacy pitfalls for the unwary. We assembled a corpus of commercial mailing-list emails, and find a network of hundreds of third parties that track email recipients via methods such as embedded pixels. About 30% of emails leak the recipient’s email address to one or more of these third parties when they are viewed. In the majority of cases, these leaks are intentional on the part of email senders, and further leaks occur if the recipient clicks links in emails. Mail servers and clients may employ a variety of defenses, but we analyze 16 servers and clients and find that they are far from comprehensive. We propose, prototype, and evaluate a new defense, namely stripping tracking tags from emails based on enhanced versions of existing web tracking protection lists.

Semantics derived automatically from language corpora contain human-like biases

Machine learning is a means to derive artificial intelligence by discovering patterns in existing data. Here, we show that applying machine learning to ordinary human language results in human-like semantic biases. We replicated a spectrum of known biases, as measured by the Implicit Association Test, using a widely used, purely statistical machine-learning model trained on a standard corpus of text from the World Wide Web. Our results indicate that text corpora contain recoverable and accurate imprints of our historic biases, whether morally neutral as toward insects or flowers, problematic as toward race or gender, or even simply veridical, reflecting the status quo distribution of gender with respect to careers or first names. Our methods hold promise for identifying and addressing sources of bias in culture, including technology.

Development and initial validation of the Cat HEalth and Wellbeing (CHEW) Questionnaire: a generic health-related quality of life instrument for cats

OBJECTIVES

The aims of the study were to define factors that owners consider relevant to the health-related quality of life (HRQoL) of cats, to develop an instrument based on this information, and to evaluate the validity and reliability of the final instrument (the Cat HEalth and Wellbeing [CHEW] Questionnaire).

METHODS

Psychometric research techniques and guidance from the US Food and Drug Administration on outcome measures were used to develop a valid and reliable instrument. Fifty-four cat owners and caregivers participated in the qualitative research, while 1303 cat owners were included in the quantitative validation phase (development dataset, n = 648; validation dataset, n = 655). A random subset of cat owners (n = 391) also participated in test-retest evaluation. Qualitative research was used to generate a draft instrument, which was then subjected to quantitative validation techniques. These included item reduction, domain identification, data quality assessment, and exploratory and confirmatory analysis to develop a final instrument, which underwent confirmatory reliability and validity assessment.

RESULTS

A draft instrument with 11 domains and 100 items based on qualitative research underwent online quantitative validation testing which refined the instrument to eight domains and 33 items. Confirmatory reliability and validity assessment showed that the final instrument had good validity, was able to discriminate between cats by age and overall health status, and demonstrated good internal and test-retest reliability.

CONCLUSIONS AND RELEVANCE

The CHEW Questionnaire was developed and validated. Additional research is needed to verify its ability to differentiate cats with and without disease, and to assess its potential as a screening tool.

Damage assessment in concrete structures using piezoelectric based sensors

Damage assessment in concrete structures using piezoelectric based sensorsABSTRACTPiezoelectric based PZT (Lead Zirconate Titanate) smart sensors offer significant potential for continuously monitoring the development and progression of internal damage in concrete structures. Changes in the resonant behavior in the measured electrical conductance obtained from electro-mechanical (EM) response of a PZT bonded to a concrete substrate is investigated for increasing levels of damage. Changes in the conductance resonant signature from EM conductance measurements are detected before visible signs of cracking. The root mean square deviation of the conductance signature at resonant peaks is shown to accurately reflect the level of damage in the substrate. The findings presented here provide a basis for developing a sensing methodology using PZT patches for continuous monitoring of concrete structures.Keywords: PZT; electro-mechanical impedance; conductance; microcracks.Evaluación de daños en estructuras de concreto utilizando sensores piezoeléctricosRESUMENLos sensores inteligentes PZT (Lead Zirconate Titanate) basados en piezoeléctricos ofrecen un potencial significativo para monitorear continuamente el desarrollo y la progresión de los daños internos en estructuras de concreto. Se investigan los cambios en el comportamiento resonante a través de la conductancia eléctrica medida, obtenida a partir de la respuesta electromecánica (EM) de un PZT unido a un sustrato de concreto para aumentar los niveles de daño. Los cambios en la resonancia de la conductancia EM se detectan antes de que aparezcan signos visibles de agrietamiento. La desviación cuadrática media de la raíz de la conductancia en los picos resonantes refleja con precisión el nivel de daño en el sustrato. Los hallazgos presentados aquí proporcionan una base para desarrollar una metodología de detección utilizando parches PZT para el monitoreo continuo de estructuras de concreto.Palabras clave: PZT; impedancia electromecánica; conductancia; microfisuras.Avaliação de danos em estruturas de concreto usando sensores piezoelétricos RESUMOOs sensores piezoelétricos inteligentes PZT (Lead Zirconate Titanate) oferecem um potencial significativo para o monitoramento contínuo do desenvolvimento e progressão de danos internos em estruturas de concreto. As alterações de ressonância através da medida da condutância elétrica obtida a partir da resposta eletromecânica (EM) de um PZT ligado a um substrato de concreto é investigada para níveis crescentes de danos. As alterações no perfil de ressonância de condutância EM são detectadas antes de sinais visíveis de fissuras. O desvio quadrático médio da raiz do perfil de condutância nos picos ressonantes é mostrado para refletir com precisão o nível de dano no substrato. Os resultados aqui apresentados fornecem uma base para o desenvolvimento de uma metodologia de detecção usando PZT para monitoramento contínuo de estruturas de concretoPalavras chave: PZT; impedância eletromecânica; condutância; microfissuras.

Oral supplementation of trans-cinnamaldehyde reduces uropathogenic Escherichia coli colonization in a mouse model

Urinary tract infections (UTIs) in the United States result in more than 7 million hospital visits per year. Uropathogenic Escherichia coli (UPEC) is responsible for more than 80% of UTIs. Although antibiotics are the drug of choice to control UTIs, their repeated use has resulted in the emergence of antibiotic-resistant UPEC. Thus, there is a need for effective alternate strategies to control UPEC infections. This study investigated the efficacy of trans-cinnamaldehyde (TC), a food-grade molecule present in cinnamon, in reducing UPEC colonization and pathogenesis in the lower UTI. Female C57BL/6 mice (6-8 weeks old) were fed ad libitum with 0, 0·1, 0·2 and 0·4% TC containing mouse chow for 10 days. Following TC supplementation, animals were experimentally infected with UPEC by transurethral catheterization. Mice were euthanized on days 1, 2 and 4 postinfection, and the bladder, urethra and urine were collected for bacterial enumeration. Prophylactic TC supplementation significantly (P ≤ 0·05) reduced UPEC colonization in the urinary bladder and urethra compared to the control. Results indicate that TC could potentially be used as an oral supplement to control UPEC-associated lower UTIs, however, follow-up clinical trials are warranted.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this study, we have demonstrated that oral supplementation of trans-cinnamaldehyde (TC) reduced uropathogenic Escherichia coli (UPEC)-associated lower urinary tract infection (UTI) in mice. Specifically, in-feed supplementation of TC significantly decreased UPEC populations in the urethra and bladder, thereby reducing the infectious load. These findings are particularly significant given the increase in incidence and prevalence of antibiotic-resistant UTIs. Our study offers new insights into the potential use of natural antimicrobials including TC, the active ingredient in cinnamon, as a nonantibiotic-based natural dietary intervention in the prophylaxis of lower UTIs.

Population Pharmacokinetics and Pharmacodynamics of the Calcimimetic Etelcalcetide in Chronic Kidney Disease and Secondary Hyperparathyroidism Receiving Hemodialysis

Etelcalcetide is a novel calcimimetic in development for the treatment of secondary hyperparathyroidism (SHPT). A population pharmacokinetic/pharmacodynamic (PK/PD) model was developed relating etelcalcetide exposures to markers of efficacy (parathyroid hormone [PTH]) and safety (calcium) using data from three clinical studies. The semimechanistic model was developed that included allosteric activation pharmacology and understanding of calcium homeostasis. The temporal profiles for all biomarkers were well described by the model. The cooperativity constant was 4.94, confirming allosteric activation mechanism. Subjects with more severe disease (higher PTH baseline) were predicted to experience less pronounced reduction in PTH (percentage change from baseline), but more reduction in calcium (Ca; percentage change from baseline). There was no evidence that dose adjustment by any covariate was needed. Model‐based simulations provided quantitative support to several elements of dosing, such as starting dose, monitoring, and titration timing for registration trials.

Inaccessible Masturbation, Impossible Mourning: Collective Melancholia, the Prohibition on Female Sexual Subjects in India, and Masturbation Fantasy as a Zone of the Strange

This paper explores a subjective experience-and identification-that a cohort of Indian women identifies as "home." This experience of "home" provides an attachment to a collective melancholia that keeps in place a prohibited female sexual subjectivity. The paper provides a brief historical overview of the prohibition of female sexual subjectivity and erotic agency in India. Following this, it discusses women's masturbation fantasies that illustrate the toggle between women's permitted and prohibited identifications. A clinical case example is presented to illustrate the hopelessness and mourning inherent in the psychoanalytic journey into subjectivity, a journey involving a departure from a shared cultural history.

Linear magnetoresistance caused by mobility fluctuations in n-doped Cd(3)As(2)

Cd(3)As(2) is a candidate three-dimensional Dirac semimetal which has exceedingly high mobility and nonsaturating linear magnetoresistance that may be relevant for future practical applications. We report magnetotransport and tunnel diode oscillation measurements on Cd(3)As(2), in magnetic fields up to 65 T and temperatures between 1.5 and 300 K. We find that the nonsaturating linear magnetoresistance persists up to 65 T and it is likely caused by disorder effects, as it scales with the high mobility rather than directly linked to Fermi surface changes even when approaching the quantum limit. From the observed quantum oscillations, we determine the bulk three-dimensional Fermi surface having signatures of Dirac behavior with a nontrivial Berry phase shift, very light effective quasiparticle masses, and clear deviations from the band-structure predictions. In very high fields we also detect signatures of large Zeeman spin splitting (g∼16).

Takotsubo cardiomyopathy following electroconvulsive therapy: an increasingly recognised phenomenon

Treatment of patients with severe depressive illnesses requiring electroconvulsive therapy (ECT) is challenging. This is compounded by the presence of physical comorbidities and potential complications. We report the case of a patient, on long-term bisoprolol, who developed acute epigastric pain and dyspnoea shortly after receiving ECT for treatment-refractory depression. An ECG showed new-onset ischaemic changes and a troponin-I level was elevated at 12 h. A diagnosis of Takotsubo cardiomyopathy was reached following angiography, which demonstrated left ventricular hypokinesia in the absence of coronary artery disease. With supportive treatment the patient made a good recovery. This report highlights the risk of developing Takotsubo cardiomyopathy following ECT despite β-adrenergic receptor blockade, and adds to a growing number of cases reporting this complication. Clinicians involved in the care of patients undergoing ECT must be aware of this complication and should consider Takotsubo cardiomyopathy in patients who develop atypical chest pain after ECT.

Redefining genomic privacy: trust and empowerment

Current models of protecting human subjects create a zero-sum game of privacy versus data utility. We propose shifting the paradigm to techniques that facilitate trust between researchers and participants.

Fulfilling the promise of the genetic revolution requires the analysis of large datasets containing information from thousands to millions of participants. However, sharing human genomic data requires protecting subjects from potential harm. Current models rely on de-identification techniques in which privacy versus data utility becomes a zero-sum game. Instead, we propose the use of trust-enabling techniques to create a solution in which researchers and participants both win. To do so we introduce three principles that facilitate trust in genetic research and outline one possible framework built upon those principles. Our hope is that such trust-centric frameworks provide a sustainable solution that reconciles genetic privacy with data sharing and facilitates genetic research.

The Dental Practice Questionnaire: a patient feedback tool for improving the quality of dental practices

BACKGROUND

The recently introduced Practice Accreditation Scheme as part of the Australian National Safety and Quality Health Service (NSQHS) standards raises the question of how dental practices can implement valid and reliable patient experience feedback mechanisms for performance evaluation and enhancement. This article describes the development and use of a dental patient questionnaire (DPQ) that can be used for this purpose.

METHODS

DPQ was piloted on 58 voluntary dental practices across Australia and resulted in an average of just over 50 patient responses to 35 practices returned. Statistical properties of the DPQ were tested through validity (construct, content and criterion), structural integrity and reliability measurements.

RESULTS

DPQ is valid and reliable, with statistical analysis showing that there are significant differences in patients' scores depending on their age, gender, regularity of visit and number of years attending the practice. Two patient satisfaction models were derived. However, there may be scope for improving DPQ to more effectively produce patient feedback on summative aspects of services provided by dental practices.

CONCLUSIONS

DPQ has been shown to be 'fit for purpose' in its first pilot and may prove to be a useful tool for supporting dental practices in the Practice Accreditation Scheme.

Post-liver transplantation sarcopenia in cirrhosis: a prospective evaluation

BACKGROUND AND AIM

Pre-transplant sarcopenia (reduced skeletal muscle mass) predicts poor outcome in cirrhosis. In contrast, whether muscle mass increases post-orthotopic liver transplantation (OLT) is not known and was studied prospectively.

METHODS

Consecutive patients who underwent a comprehensive nutritional evaluation in a liver transplant nutrition clinic were included. Core abdominal muscle area was measured on abdominal computed tomography obtained pre- and post-OLT. Age- and gender-based controls were used to define sarcopenia. Measures of body composition pre-transplant were correlated with computed tomography measurements. Predictors and clinical impact of post-OLT change in muscle area were examined. In three subjects post-OLT and three controls, expression of genes regulating skeletal muscle mass were quantified.

RESULTS

During the study period, 53 patients (M:F 41:12; age 56.9 ± 7.5 years) were followed up after OLT for 19.3 ± 9 months. Five patients died and another five had acute graft rejection. Pre-OLT sarcopenia was present in 33 (66.2%). Pre-transplant clinical characteristics including Child's score, MELD score, and nutritional status or post-transplantation immunosuppression regimen did not predict post-transplant change in muscle mass. New onset post-OLT sarcopenia developed in 14 patients. Loss of muscle mass post-OLT increased risk of diabetes mellitus and a trend toward higher mortality. Skeletal muscle expression of myostatin was higher and that of ubiquitin proteasome proteolytic components lower post-OLT than in controls.

CONCLUSIONS

Post-transplantation sarcopenia is common and could not be attributed to pre-transplant characteristics or the type or duration of post-OLT immunosuppression. Post-transplant sarcopenia contributes to adverse consequences and strategies targeting myostatin may be beneficial.

Routes for breaching and protecting genetic privacy

We are entering an era of ubiquitous genetic information for research, clinical care and personal curiosity. Sharing these data sets is vital for progress in biomedical research. However, a growing concern is the ability to protect the genetic privacy of the data originators. Here, we present an overview of genetic privacy breaching strategies. We outline the principles of each technique, indicate the underlying assumptions, and assess their technological complexity and maturation. We then review potential mitigation methods for privacy-preserving dissemination of sensitive data and highlight different cases that are relevant to genetic applications.

Post-liver transplantation sarcopenia in cirrhosis: a prospective evaluation

BACKGROUND AND AIM

Pre-transplant sarcopenia (reduced skeletal muscle mass) predicts poor outcome in cirrhosis. In contrast, whether muscle mass increases post-orthotopic liver transplantation (OLT) is not known and was studied prospectively.

METHODS

Consecutive patients who underwent a comprehensive nutritional evaluation in a liver transplant nutrition clinic were included. Core abdominal muscle area was measured on abdominal computed tomography obtained pre- and post-OLT. Age- and gender-based controls were used to define sarcopenia. Measures of body composition pre-transplant were correlated with computed tomography measurements. Predictors and clinical impact of post-OLT change in muscle area were examined. In three subjects post-OLT and three controls, expression of genes regulating skeletal muscle mass were quantified.

RESULTS

During the study period, 53 patients (M:F 41:12; age 56.9 ± 7.5 years) were followed up after OLT for 19.3 ± 9 months. Five patients died and another five had acute graft rejection. Pre-OLT sarcopenia was present in 33 (66.2%). Pre-transplant clinical characteristics including Child's score, MELD score, and nutritional status or post-transplantation immunosuppression regimen did not predict post-transplant change in muscle mass. New onset post-OLT sarcopenia developed in 14 patients. Loss of muscle mass post-OLT increased risk of diabetes mellitus and a trend toward higher mortality. Skeletal muscle expression of myostatin was higher and that of ubiquitin proteasome proteolytic components lower post-OLT than in controls.

CONCLUSIONS

Post-transplantation sarcopenia is common and could not be attributed to pre-transplant characteristics or the type or duration of post-OLT immunosuppression. Post-transplant sarcopenia contributes to adverse consequences and strategies targeting myostatin may be beneficial.

Hyperammonemia-mediated autophagy in skeletal muscle contributes to sarcopenia of cirrhosis

Hyperammonemia and sarcopenia (loss of skeletal muscle) are consistent abnormalities in cirrhosis and portosystemic shunting. We have shown that muscle ubiquitin-proteasome components are not increased with hyperammonemia despite sarcopenia. This suggests that an alternative mechanism of proteolysis contributes to sarcopenia in cirrhosis. We hypothesized that autophagy could be this alternative pathway since we observed increases in classic autophagy markers, increased LC3 lipidation, beclin-1 expression, and p62 degradation in immunoblots of skeletal muscle protein in cirrhotic patients. We observed similar changes in these autophagy markers in the portacaval anastamosis (PCA) rat model. To determine the mechanistic relationship between hyperammonemia and autophagy, we exposed murine C(2)C(12) myotubes to ammonium acetate. Significant increases in LC3 lipidation, beclin-1 expression, and p62 degradation occurred by 1 h, whereas autophagy gene expression (LC3, Atg5, Atg7, beclin-1) increased at 24 h. C(2)C(12) cells stably expressing GFP-LC3 or GFP-mCherry-LC3 constructs showed increased formation of mature autophagosomes supported by electron microscopic studies. Hyperammonemia also increased autophagic flux in mice, as quantified by an in vivo autophagometer. Because hyperammonemia induces nitration of proteins in astrocytes, we quantified global muscle protein nitration in cirrhotic patients, in the PCA rat, and in C(2)C(12) cells treated with ammonium acetate. Increased protein nitration was observed in all of these systems. Furthermore, colocalization of nitrated proteins with GFP-LC3-positive puncta in hyperammonemic C(2)C(12) cells suggested that autophagy is involved in degradation of nitrated proteins. These observations show that increased skeletal muscle autophagy in cirrhosis is mediated by hyperammonemia and may contribute to sarcopenia of cirrhosis.