Autobiologies on YouTube: narratives of direct-to-consumer genetic testing

Despite a growing personal genomics market, little is known about how people engage with the possibilities offered by direct-to-consumer (DTC) genetic testing. In order to help address this gap, this study deploys narrative analysis of YouTube videos posted by individuals who have purchased DTC genetic testing for disease. Genetic testing is said to be contributing to new states of illness, where individuals may become “patients-in-waiting.” In the videos analyzed, we found a new form of storytelling about this ambiguous state of illness, which we refer to as autobiology. Autobiology – the study of, and story about, one's own biology – concerns narratives of sense-making through forms of biological practice, as well as wayfaring narratives which interweave genetic markers and family histories of disease. These autobiologies – part of a broader shift toward public stories about genetics and other healthcare technologies – exhibit playfulness, as well as being bound with consumerist practices.     

“It just becomes much more complicated”: Genetic counselors' views on genetics and prenatal testing

Many social scientists and commentators have expressed concerns about the acceleration of genetic medicine and testing in the last few decades. While there is a growing body of work on how patients and the lay public view the potential of genetic medicine, there remains relatively little social science research on the personal and professional views of master's-trained genetic counselors, a growing profession of clinicians who are often the key medical actors translating increasingly complex genetic information to patients. This study begins to fill in this lacuna by examining the perspectives of 26 genetic counselors in the USA on some of the central bioethical concerns raised by genetic testing, with a particular focus on prenatal testing. The study finds that while there is general enthusiasm for genetic medicine, and prenatal testing in particular, genetic counselors also have reflexive ambivalence, expressing both skepticism and concern about the usefulness and consequences of acquiring genetic information.     

From lab to lifestyle: translating genomics into healthcare practices

Contemporary genomic sciences are uncovering genetic factors implicated in common complex diseases such as type 2 diabetes. It is suggested that such knowledge could be developed into tests for susceptibility to the disease that would allow preventive action through lifestyle modification. This paper presents research on responses to this suggestion by genetic specialists, diabetologists, and general practitioners – three groups of health professionals whose practices are likely to be affected by such testing services. It shows how the responses of the different groups are related to the professional culture of practice. I suggest that the perspective a profession has of its potential role in relation to the emerging technology can illuminate the early stages of co-constitution by which the technology that is used and the community of practice that use it are mutually reshaped.     

Are multiple predator effects directed by prey availability?

Antagonistic/synergistic interactions among predators foraging on the same prey have been assumed to play a major role in shaping community structure. Studies in systems with multiple predator species have shown that the strength of these interactions may not be predictable and is largely dependent on individual behavioural traits, species density and habitat complexity. Although the association of prey consumption and satiation of a foraging predator has long been recognized, there has been relatively little research on how prey availability affects multiple predators’ effects. In this work, we present a framework to investigate the variation in two coexisting/competing predators’ effects on prey risk as affected by the prey availability rate. Functional responses by each predator species were first studied in single-predator treatments. Then, the intra- and inter-specific competition was investigated by employing additive and substitutative experimental designs to highlight the nature of multiple effects. Intra- and interspecific interactions were found to be similar and there was risk reduction, and risk enhancement for the prey at intermediate and high levels, respectively, according to the multiplicative risk model (MRM). The results indicated that when similar predators are concerned, the outcomes of MRM may vary according to the functional response curve of these predators. Thus, studies involving a wide range of prey densities are required to explore the nature of interactions. Moreover, this kind of experimental data can contribute to unravelling complexities in theoretical approaches by earlier studies and ultimately promote understanding the effect of multiple predators on prey population regulation.     

Reading the runes of my genome: a personal exploration of retail genetics

Since 2007, retail genetic companies have offered personal genome scans: DNA testing based on single nucleotide polymorphisms (SNPs) which are interpreted to provide genetic risks of some common diseases and trait information. There is much discussion of the validity, benefits and risks of this testing, and its ethics and regulation, but little information about the experiences of those who have purchased this testing. This paper offers an autobiographical ethnography, describing the author's use of genome scans purchased from deCODEme and 23andMe. The genetic disease risks provided were generally very modest and there were significant variations in the risks from the two companies. Risks were skeptically interpreted through a frame of knowledge of family disease histories. It is suggested that this personal medicine is likely to disappoint and it does not live up to its claims. Rather than being empowering personalized medicine, these scans are a geneticized medicine of the genomic person.     

Approval policies for modifications to machine learning‐based software as a medical device: A study of bio‐creep

Successful deployment of machine learning algorithms in healthcare requires careful assessments of their performance and safety. To date, the FDA approves locked algorithms prior to marketing and requires future updates to undergo separate premarket reviews. However, this negates a key feature of machine learning—the ability to learn from a growing dataset and improve over time. This paper frames the design of an approval policy, which we refer to as an automatic algorithmic change protocol (aACP), as an online hypothesis testing problem. As this process has obvious analogy with noninferiority testing of new drugs, we investigate how repeated testing and adoption of modifications might lead to gradual deterioration in prediction accuracy, also known as “biocreep” in the drug development literature. We consider simple policies that one might consider but do not necessarily offer any error‐rate guarantees, as well as policies that do provide error‐rate control. For the latter, we define two online error‐rates appropriate for this context: bad approval count (BAC) and bad approval and benchmark ratios (BABR). We control these rates in the simple setting of a constant population and data source using policies aACP‐BAC and aACP‐BABR, which combine alpha‐investing, group‐sequential, and gate‐keeping methods. In simulation studies, bio‐creep regularly occurred when using policies with no error‐rate guarantees, whereas aACP‐BAC and aACP‐BABR controlled the rate of bio‐creep without substantially impacting our ability to approve beneficial modifications.     

Diagnostic approach in patients with angina and no obstructive coronary artery disease: emphasising the role of the coronary function test

BackgroundMany patients with angina do not have obstructive coronary artery disease (CAD), also referred to as “Ischaemia with No Obstructive Coronary Arteries“ (INOCA). Coronary vascular dysfunction is the underlying cause of this ischaemic heart disease in as much as 59–89% of these patients, including the endotypes of coronary microvascular dysfunction and epicardial coronary vasospasm. Currently, a coronary function test (CFT) is the only comprehensive diagnostic modality to evaluate all endotypes of coronary vascular dysfunction in patients with INOCA.ObjectiveIn this paper we discuss the relevance of performing a CFT, provide considerations for patient selection, and present an overview of the procedure and its safety.MethodsWe reviewed the latest published data, guidelines and consensus documents, combined with a discussion of novel original data, to present this point of view.ResultsThe use of a CFT could lead to a more accurate and timely diagnosis of vascular dysfunction, identifies patients at risk for cardiovascular events, and enables stratified treatment which improves symptoms and quality of life. Current guidelines recommend considering a CFT in patients with INOCA and persistent symptoms. The safety of the procedure is comparable to that of a regular coronary angiography with physiological measurements. Non-invasive alternatives have limited diagnostic accuracy for the identification of coronary vascular dysfunction in patients with INOCA, and a regular coronary angiography and/or coronary computed tomography scan cannot establish the diagnosis.ConclusionsA complete CFT, including acetylcholine and adenosine tests, should be considered in patients with INOCA.Supplementary InformationThe online version of this article (10.1007/s12471-020-01532-9) contains supplementary material, which is available to authorized users.     

上肢精准电磁功率计（臂力计）用于心肺代谢等整体功能评估的临床观察研究*

目的: 受试者分别用上肢（臂力计）和下肢精准电磁功率计（自行车）进行症状限制性极限心肺运动试验（CPET）,分析探讨上肢CPET的临床价值。方法: 15例受试者（正常人6例和慢病患者9例）签署知情同意书后在不同的2 d里分别完成上肢和下肢精准电磁功率计CPET,分析CPET数据、计算相关核心指标,探究上肢和下肢CPET的异同及其相关性。结果: ①全体15例受试者男8女7,其中6例正常人和9例慢病患者亚组相比仅年龄（（33.2±12.7）比（53.6±8.5）岁）和无诊断疾病有显著差异（P<0.05）。②全体受试者上肢CPET峰值心率（（131.0±19.0）比（153.0±22.0） bpm,P<0.05）和血压均低于下肢CPET,但血压差异无统计学意义（P>0.05）;上肢CPET的峰值潮气量（（1.3±0.4）比（1.8±0.4） L）和分钟通气量（（51.4±21.1）比（67.9±22.1） L/min）均显著低于下肢（P均<0.05）,而峰值呼吸频率无显著差异;采用上肢CPET时,运动时间（（6.4±0.6）比（8.5±1.2） min）要短于下肢CPET;峰值负荷功率（（73.2±19.6）比（158.5±40.3）W/min）、峰值摄氧量（（1.1±0.4）比（1.7±0.4）L/min）、无氧阈（（0.6±0.2）比（0.9±0.2） L/min）、峰值氧脉搏（（8.6±2.3）比（10.9±2.6） ml/beat）、摄氧通气效率峰值平台（34.7±4.3比39.8±5.3）均较低,而二氧化碳排出通气效率最小值（32.6±3.8比28.7±4.9）及斜率（33.9±4.3比28.3±6.2）高于下肢CPET（P均<0.05）。正常人和慢病两亚组各自的比较结果与整体比较结果无显著差异。③上肢CPET的运动时间,峰值心率,峰值呼吸频率、潮气量、分钟通气量,峰值负荷功率实测值及百分预计值,峰值摄氧量实测值、公斤体重值和百分预计值,无氧阈实测值、公斤体重值,峰值氧脉搏的实测值,摄氧通气效率峰值平台、二氧化碳排出通气效率最小值和斜率的实测值及百分预计值与下肢CPET的结果相关性较好,其余指标无显著相关性。结论: 作为下肢CPET的补充,上肢CPET用于整体功能状态评估具有极高的可行性和更高的安全性,对于指导安全有效个体化精准运动整体方案的实施提供了重要补充,值得进一步深入探究。     

肺动脉高压及其合并心脏内右向左分流患者的心肺运动试验特征性变化的临床研究*

目的: 明确肺动脉高压及合并心脏内右向左分流（R-L）患者的心肺运动试验（CPET）气体交换变化。方法: 本文通过回顾性分析阜外医院从2016-10至2017-08签署知情同意书后完成CPET的73例肺动脉高压病人CPET数据,采取双盲方式抽取四位医生作为判读者分别独立识别R-L后,结果分为四组：①分流阳性组（n=20）、②分流可疑组（n=9）、③无分流组（n=37）、④分流延迟开放组（n=6）。选择同期完成CPET正常人14例作为对照。结果: 分流阳性组在运动开始时分钟通气量、二氧化碳排出通气效率、氧气通气效率和呼气末氧分压相对于静息期的改变值骤升,分别为（7.36±2.72） L/min、（1.84±3.59）、（5.02±4.34）、（3.75±2.64） mmHg）,明显高于对照组的（（4.26±2.59） L/min、（2.22±2.08）、（-1.46±4.68）、（-3.96±2.82） mmHg）;而呼气末二氧化碳分压相对于静息期的改变值骤降（-1.63±1.66） mmHg,明显低于对照组的（2.22±2.08） mmHg（P均<0.01）。分流延迟开放组在运动后期呼吸商（RER）、二氧化碳排出通气效率、氧气通气效率和呼气末氧分压相对于静息期的改变值骤升,分别为（0.40±0.08）、（11.07±5.60）、（30.55±7.89）、（13.72±2.21） mmHg,明显高于对照组的（0.38±0.12）、（5.67±4.6）、（4.54±3.83）、（5.51±4.24） mmHg;而呼气末二氧化碳分压相对于静息期的改变值骤降（-6.82±1.96） mmHg,明显区别于对照组的（5.67±4.6） mmHg,在恢复期分流延迟开放组二氧化碳排出通气效率、氧气通气效率相对于峰值功率时的改变值（分别为-8.38±3.24、-13.14±6.47）,明显低于对照组（6.22±2.87、16.56±4.2）（P均<0.01）。结论: 肺动脉高压患者较正常人CPET的整体功能和通气效率指标降低;肺动脉高压合并右向左分流患者不仅在静息通气效率受限更剧;且特征性地运动初始时出现PETO₂明显上升、PETCO₂明显下降,RER跳升到1.0左右,VE/VCO₂ 不降反升与VO₂/VE不升反降, 常有SpO₂显著下降,还有VE更大幅度上升;延迟开放型上述特征性变化发生在运动接近峰值的1~3 min而非运动初始,且运动停止后迅速反向变回以示重新关闭。