How accurate are digital symptom assessment apps for suggesting conditions and urgency advice? A clinical vignettes comparison to GPs

OBJECTIVES

To compare breadth of condition coverage, accuracy of suggested conditions and appropriateness of urgency advice of eight popular symptom assessment apps.

DESIGN

Vignettes study.

SETTING

200 primary care vignettes.

INTERVENTION/COMPARATOR

For eight apps and seven general practitioners (GPs): breadth of coverage and condition-suggestion and urgency advice accuracy measured against the vignettes' gold-standard.

PRIMARY OUTCOME MEASURES

(1) Proportion of conditions 'covered' by an app, that is, not excluded because the user was too young/old or pregnant, or not modelled; (2) proportion of vignettes with the correct primary diagnosis among the top 3 conditions suggested; (3) proportion of 'safe' urgency advice (ie, at gold standard level, more conservative, or no more than one level less conservative).

RESULTS

Condition-suggestion coverage was highly variable, with some apps not offering a suggestion for many users: in alphabetical order, Ada: 99.0%; Babylon: 51.5%; Buoy: 88.5%; K Health: 74.5%; Mediktor: 80.5%; Symptomate: 61.5%; Your.MD: 64.5%; WebMD: 93.0%. Top-3 suggestion accuracy was GPs (average): 82.1%±5.2%; Ada: 70.5%; Babylon: 32.0%; Buoy: 43.0%; K Health: 36.0%; Mediktor: 36.0%; Symptomate: 27.5%; WebMD: 35.5%; Your.MD: 23.5%. Some apps excluded certain user demographics or conditions and their performance was generally greater with the exclusion of corresponding vignettes. For safe urgency advice, tested GPs had an average of 97.0%±2.5%. For the vignettes with advice provided, only three apps had safety performance within 1 SD of the GPs-Ada: 97.0%; Babylon: 95.1%; Symptomate: 97.8%. One app had a safety performance within 2 SDs of GPs-Your.MD: 92.6%. Three apps had a safety performance outside 2 SDs of GPs-Buoy: 80.0% (p<0.001); K Health: 81.3% (p<0.001); Mediktor: 87.3% (p=1.3×10^-3).

CONCLUSIONS

The utility of digital symptom assessment apps relies on coverage, accuracy and safety. While no digital tool outperformed GPs, some came close, and the nature of iterative improvements to software offers scalable improvements to care.

1H, 13C, and 15N backbone chemical shift assignments of the apo and the ADP-ribose bound forms of the macrodomain of SARS-CoV-2 non-structural protein 3b

The SARS-CoV-2 genome encodes for approximately 30 proteins. Within the international project COVID19-NMR, we distribute the spectroscopic analysis of the viral proteins and RNA. Here, we report NMR chemical shift assignments for the protein Nsp3b, a domain of Nsp3. The 217-kDa large Nsp3 protein contains multiple structurally independent, yet functionally related domains including the viral papain-like protease and Nsp3b, a macrodomain (MD). In general, the MDs of SARS-CoV and MERS-CoV were suggested to play a key role in viral replication by modulating the immune response of the host. The MDs are structurally conserved. They most likely remove ADP-ribose, a common posttranslational modification, from protein side chains. This de-ADP ribosylating function has potentially evolved to protect the virus from the anti-viral ADP-ribosylation catalyzed by poly-ADP-ribose polymerases (PARPs), which in turn are triggered by pathogen-associated sensing of the host immune system. This renders the SARS-CoV-2 Nsp3b a highly relevant drug target in the viral replication process. We here report the near-complete NMR backbone resonance assignment (¹H, ¹³C, ¹⁵N) of the putative Nsp3b MD in its apo form and in complex with ADP-ribose. Furthermore, we derive the secondary structure of Nsp3b in solution. In addition, ¹⁵N-relaxation data suggest an ordered, rigid core of the MD structure. These data will provide a basis for NMR investigations targeted at obtaining small-molecule inhibitors interfering with the catalytic activity of Nsp3b.

Transient Rotamerism and Photoisomerization Dynamics of trans- and cis-Naphthylstilbene

The rotamerism and photoisomerization of trans- and cis-1,2-di-(2-naphthyl)ethylene (tN and cN) are studied with stationary and transient absorption spectroscopies assisted by quantum chemical calculations. Absorption and emission spectra of rotamers (rotational isomers) tN-S (C_2h-symmetric), tN-A (C₁), and tN-S' (C₂) are derived with a 53:47 ratio of tN-S to tN-A. Upon photoexcitation, the equilibration of the rotamers in S₀ (rotamerization) is observed in the bleach region with characteristic time τ_rotamer ≈ 0.5 ns. With excitation at 364 nm, the S₀ equilibrium shifts because, mainly, tN-A is bleached and the rotamerization becomes traceable, whereas with excitation at 345 nm, the equilibrium is preserved and the bleach spectrum remains unchanged. It is just long-lived (∼2 ns) S₁ that allows for monitoring the rotamer dynamics in S₀. Replacement of the stilbene phenyl rings with larger naphthyls increases the S₁ → P torsional barrier E_1act toward perpendicular configuration P both from cis and trans configurations. In tN, the radiative relaxation with τ_R ≈ 3.7 ns becomes the main deactivation channel, and accordingly, the measured decays show nearly no dependence on the solvent viscosity. The cis-to-trans photoisomerization occurs via two paths: adiabatic cS₁ → P → tS₁ (20%) and more common nonadiabatic cS₁ → P → S₀ (80%). The barrier cS₁ → P in the cis-isomer is reduced in polar solvents because of a zwitterionic character of P. The P-state is directly detected with the cN isomer in acetonitrile by an excited-state absorption band at 400 nm developing with 0.7 ps and decaying with 1.6 ps. Two dihydrophenanthrene (DHP)-like products result from photoexcited cN. The metastable DHP-A builds up transiently from cN-A, and its spectrum at about 550 nm matches the published DHP absorption. The stable DHP-S' accumulates under stationary illumination and is formed either from excited cN-S' or metastable DHP-A.

A novel microchip-based imaged CIEF-MS system for comprehensive characterization and identification of biopharmaceutical charge variants

A microfluidic system has been designed that integrates both imaged capillary isoelectric focusing (iCIEF) separations and downstream MS detection into a single assay. Along with the construction of novel instrumentation and an innovative microfluidic chip, conversion to MS‐compatible separation reagents has also been established. Incorporation of 280 nm absorbance iCIEF‐MS analysis not only permits photometric quantitation of separated charge isoforms but also facilitates the direct monitoring of analyte focusing and mobilization in real‐time. The outcome of this effort is a device with the unique ability to allow for both the characterization and identification of protein charge and mass isoforms in under 15 min. Acquisition, quantitation, and identification of highly resolved intact mAb charge isoforms along with their critical N‐linked glycan pairs clearly demonstrate analytical utility of our innovative system. In total, 33 separate molecular features were characterized by the iCIEF‐MS system representing a dramatic increase in the ability to monitor multiple intact mAb critical quality attributes in a single comprehensive assay. Unlike previously reported CIEF‐MS results, relatively high ampholyte concentrations, of up to 4% v/v, were employed without impacting MS sensitivity, observed to be on the order of 1% composition.

Follow the Light - From Low-Energy Defibrillation to Multi-Site Photostimulation

One major cause of death in the industrialized world is sudden cardiac death, which so far can be reliably treated only by applying strong electrical shocks. Developing improved methods, aiming at lowering shock intensity and associated side effects potentially has significant clinical implications. Thus, optogenetic stimulation using structured illumination has been introduced as a promising experimental tool to investigate mechanisms underlying multi-site pacing and to optimize potential low-energy approaches. Furthermore, an objective of this work is to strengthen the application of optogenetic tools for cardiac arrhythmia research, which in turn is expected to improve applicable technologies towards tissue-protective defibrillation.

Fluid Imprint and Inertial Switching in Ferroelectric La:HfO2 Capacitors

Ferroelectric (FE) HfO₂-based thin films, which are considered as one of the most promising material systems for memory device applications, exhibit an adverse tendency for strong imprint. Manifestation of imprint is a shift of the polarization-voltage (P-V) loops along the voltage axis due to the development of an internal electric bias, which can lead to the failure of the writing and retention functions. Here, to gain insight into the mechanism of the imprint effect in La-doped HfO₂ (La:HfO₂) capacitors, we combine the pulse switching technique with high-resolution domain imaging by means of piezoresponse force microscopy. This approach allows us to establish a correlation between the macroscopic switching characteristics and domain time-voltage-dependent behavior. It has been shown that the La:HfO₂ capacitors exhibit a much more pronounced imprint compared to Pb(Zr,Ti)O₃-based FE capacitors. Also, in addition to conventional imprint, which evolves with time in the poled capacitors, an easily changeable imprint, termed as "fluid imprint", with a strong dependence on the switching prehistory and measurement conditions, has been observed. Visualization of the domain structure reveals a specific signature of fluid imprint-continuous switching of polarization in the same direction as the previously applied field that continues a long time after the field was turned off. This effect, termed as "inertial switching", is attributed to charge injection and subsequent trapping at defect sites at the film-electrode interface.

No light without the dark: Perspectives and hindrances for translation of cardiac optogenetics

Over the last decade, optogenetic stimulation of the heart and its translational potential for rhythm control attracted more and more interest. Optogenetics allows to stimulate cardiomyocytes expressing the light-gated cation channel Channelrhodopsin 2 (ChR2) with light and thus high spatio-temporal precision. Therefore this new approach can overcome the technical limitations of electrical stimulation. In regard of translational approaches, the prospect of pain-free stimulation, if ChR2 expression is restricted to cardiomyocytes, is especially intriguing and could be highly beneficial for cardioversion and defibrillation. However, there is no light without shadow and cardiac optogenetics has to surmount critical hurdles, namely "how" to inscribe light-sensitivity by expressing ChR2 in a native heart and how to avoid side effects such as possible immune responses against the gene transfer. Furthermore, implantable light devices have to be developed which ensure sufficient illumination in a highly contractile environment. Therefore this article reviews recent advantages in the field of cardiac optogenetics with a special focus on the hindrances for the potential translation of this new approach into clinics and provides an outlook how these have to be carefully investigated and could be solved step by step.

P03.04 Signaling questions assessing brain tumor patients’ distress in clinical routine - a feasibility study

BACKGROUND

Approximately 20%-35% of patients with intracranial tumors show depressive symptoms and distress. Assessment in these patients remains challenging due to cognitive and/or neurological deficits. We developed 3 signaling questions in order to assess patients during patient-doctor consultation. The aim is to implement them in clinical routine and to compare the results with patient reported outcome measures (PROMs) along disease trajectory.

MATERIAL AND METHODS

Patients were prospectively examined in a structured interview applying the 3 following questions: 1),Has your mood worsened? (I)”; 2),Are you strained by physical changes? (II)”; 3),Has your faculty of thought decreased? (III)”. Simultaneously, patients filled in the Distress Thermometer (DT) and the EORTC QLQ-C30 + BN20. The first patient group was assessed twice pre- and postoperatively in the very early disease trajectory (A), the second patient group once in the outpatient setting during adjuvant therapy or follow-up (B). The results of the 3 signaling questions were compared to the results of the PROMs.

RESULTS

A total of n=62 patients gave informed consent and n= 61 were assessed so far. In general, the signaling questions were feasible to answer for all patients. However, patients frequently needed more detailed examples for symptoms emphasizing the intention of the question.

In group A (n= 20), patients had a mean age of 59 years, n= 12 (60%) were male. Main diagnoses were glioblastomas, meningiomas and metastases. The results of the signaling questions did not reflect the screening by DT: N= 11 (55%) reported that their mood has worsened (I) prior to the operation, which then improved to n= 5 (31%) patients afterwards. The same applied to physical changes (II, 10 (50%) vs. 7 (44%), as well as lower cognition (III, 7 (35%) vs. 4 (25%) respectively). In contrast, mean DT (5.7 vs. 6 after) as well as the mean number of positive responses to the problem lists on the DT was similar pre- and postoperatively (8.7 pre-op vs. 9.4 post-op).

Group B, (n= 41) consisted of patients harboring malignant gliomas, n= 27 (66%) were male. Patients had a mean DT score = 6.8, n= 22 (53%) named a worse mood (I), n= 23 (56%) patients reported physical changes (II) and n= 22 (54%) patients reported lower cognition (III), global health scale (GHS) according to the EORTC instrument was 60 (0–100). The majority of patients with a DT ≥6 also reported strain in the signaling questions and had a lower mean GHS = 54,8. DT ≥ 6 was linked to worse mood (I, Fishers exact, p=0.02).

CONCLUSION

According to our preliminary data, the signaling questions seem to be more useful in the outpatient setting in glioma patients than perioperatively. “Has your mood worsened” was associated with higher burden according to DT. Screening in brain tumor patients could probably complemented by direct questions in order to avoid missing patients who are not able to fill in questionnaires.

Setup for multicoincidence experiments of photons in the extreme ultraviolet to visible spectral range and charged particles-The solid angle maximization approach

The coincident detection of particles is a powerful method in experimental physics, enabling the investigation of a variety of projectile-target interactions. The vast majority of coincidence experiments is performed with charged particles, as they can be guided by electric or magnetic fields to yield large detection probabilities. When a neutral species or a photon is one of the particles recorded in coincidence, its detection probability typically suffers from small solid angles. Here, we present two optical assemblies considerably enhancing the solid angle for photon detection in the extreme ultraviolet to visible spectral range. The efficiency and versatility of these assemblies are demonstrated for electron-photon coincidence detection, where electrons and photons emerge from fundamental processes after photoexcitation of gaseous samples by synchrotron radiation.

Uncovering the (un-)occupied electronic structure of a buried hybrid interface

The energy level alignment at organic/inorganic (o/i) semiconductor interfaces is crucial for any light-emitting or -harvesting functionality. Essential is the access to both occupied and unoccupied electronic states directly at the interface, which is often deeply buried underneath thick organic films and challenging to characterize. We use several complementary experimental techniques to determine the electronic structure of p -quinquephenyl pyridine (5P-Py) adsorbed on ZnO(1 0   -1 0). The parent anchoring group, pyridine, significantly lowers the work function by up to 2.9 eV and causes an occupied in-gap state (IGS) directly below the Fermi level E _F. Adsorption of upright-standing 5P-Py also leads to a strong work function reduction of up to 2.1 eV and to a similar IGS. The latter is then used as an initial state for the transient population of three normally unoccupied molecular levels through optical excitation and, due to its localization right at the o/i interface, provides interfacial sensitivity, even for thick 5P-Py films. We observe two final states above the vacuum level and one bound state at around 2 eV above E _F, which we attribute to the 5P-Py LUMO. By the separate study of anchoring group and organic dye combined with the exploitation of the occupied IGS for selective interfacial photoexcitation, this work provides a new pathway for characterizing the electronic structure at buried o/i interfaces.