The potential of paper-based diagnostics to meet the ASSURED criteria

Paper-based diagnostics have already revolutionized point-of-care approaches for health and environmental applications, by providing low-cost, disposable tools that can be utilized in remote settings. These devices typically consist of microfluidic, chemical, and biological diagnostic components implemented on paper substrates, towards addressing the ASSURED (Affordable, Sensitive, Specific, User friendly, Rapid and Robust, Equipment free and Deliverable to end users) principles set out by the World Health Organization. Paper-based diagnostics primarily contribute to the affordable, equipment-free, and deliverable-to-end-user aspects. However, additional functionality must be integrated with paper-based diagnostic devices to achieve truly ASSURED solutions. Advances in printed electronics provide a fitting foundation for implementing augmented functionality, while maintaining the affordability and disposability of paper-based diagnostics. This paper reviews the printed functional building blocks that contribute towards achieving this goal, from individual printed electronic components to fully integrated solutions. Important modules for sensing, read-out of results, data processing and communication, and on-board power are explored, and solutions printed on flexible or paper-based substrates for integration with paper-based diagnostics are considered. Although many of the unit operations required to achieve the ASSURED criteria can be implemented using paper, basic system functionality is still lacking, and this requires a concerted effort in integration of the various components for truly ASSURED solutions to be realized. Beyond ASSURED, modern clinical practises and crisis readiness also require additional informational functionality, which a systems approach using paper-based solutions could ensure.

A review of printed functionalities towards integrated paper-based diagnostics that fully meet the ASSURED principles.     

Germany’s next shutdown—Possible scenarios and outcomes

With the rapid increase of reported COVID‐19 cases, German policymakers announced a 4‐week “shutdown light” starting on November 2, 2020. Applying mathematical models, possible scenarios for the evolution of the outbreak in Germany are simulated. The results indicate that independent of the effectiveness of the current restrictive measures they might not be sufficient to mitigate the outbreak. Repeated shutdown periods or permanently applied measures over the winter could be successful alternatives.     

X-ray Absorption (XRA): A New Technique for the Characterization of Granular Activated Carbons

The X-ray absorption (XRA) method using digital image processing techniques is a reliable technique to determine the exhaustion degree of granular activated carbons (GACs). Using an innovative digital image processing technique, the identification of individual adsorbed molecules or ions in a GAC was possible. Adsorption isotherm models (Langmuir and Freundlich) were used to simulate the adsorption equilibrium data of Methylene Blue (MB), nickel, cobalt and iodine. Freundlich equation was found to have the highest value of R² compared with Langmuir. The identification of distinctive patterns applying XRA for different adsorbed ions and molecules onto GAC was explored. It is demonstrated that unique XRA configurations for each adsorbed ion or molecule are found, as well as a proportional relationship between its incident energy (needed to achieve maximum photon attenuation) and the (effective) atomic number, the adsorbate mass and the molar or atomic mass of adsorbed molecule or ion. XRA method in combination with image histogram modifications was used to obtain a digital signature of adsorbed ions/molecules, giving distinct GSI values for each one in the used energy range. Probabilistic models prove that XRA results are within relationships between effective atomic number and photonic interaction probability, reinforcing the potentialities of XRA for monitoring (multi-)ion and/or molecule combinations on GAC using advanced digital image processing techniques. It was proved that the proposed approach could assess different adsorbed ions/molecules onto GACs in water purification systems.     

Magnetic-resonance-imaging-based three-dimensional muscle reconstruction of hip abductor muscle volume in a person with a transfemoral bone-anchored prosthesis: A feasibility study

Background: Persons with transfemoral amputation typically have severe muscle atrophy of the residual limb. The effect of bone-anchored prosthesis use on existing muscle atrophy is unknown. A potentially feasible method to evaluate this is magnetic resonance imaging (MRI)-based three-dimensional (3D) muscle reconstruction. We aimed to (1) examine the feasibility of MRI-based 3D muscle reconstruction technique in a person with a cobalt–chrome–molybdenum transfemoral bone-anchored prosthesis; and (2) describe the change of hip abductor muscle volume over time. Methods: In this single case, 1-year follow-up study we reconstructed the 3D hip abductor muscle volumes semiautomatically from MRI scans at baseline, 6- and 12-month follow-up. The number of adverse events, difficulties in data analysis, time investment and participants’ burden determined the level of feasibility. Results: We included a man (70 years) with a transfemoral amputation who received a bone-anchored prosthesis after 52 years of socket prosthesis use. No adverse events occurred. The accuracy of the 3D reconstruction was potentially reduced by severe adipose tissue interposition. Data analysis was time-intensive (115 h). Participants’ burden was limited to 3-h time investment. Compared to baseline, the total hip abductor volume of both the residual limb (6 month: 5.5%; 12 month: 7.4%) and sound limb (6 month: 7.8%; 12 month: 5.5%) increased. Conclusion: The presented technique appears feasible to follow muscle volume changes over time in a person with a cobalt–chrome–molybdenum transfemoral bone-anchored prosthesis in an experimental setting. Future research should focus on analysis of muscle tissue composition and the feasibility in bone-anchored prostheses of other alloys.     

Bichat guidelines for the clinical management of anthrax and bioterrorism-related anthrax

The spore-forming Bacillus anthracis must be considered as one of the most serious potential biological weapons. The recent cases of anthrax caused by a deliberate release reported in 2001 in the United States point to the necessity of early recognition of this disease. Infection in humans most often involves the skin, and more rarely the lungs and the gastrointestinal tract. Inhalational anthrax is of particular interest for possible deliberate release: it is a life-threatening disease and early diagnosis and treatment can significantly decrease the mortality rate. Treatment consists of massive doses of antibiotics and supportive care. Isolation is not necessary. Antibiotics such as ciprofloxacin are recommended for post-exposure prophylaxis during 60 days.     

A solitary chest wall metastasis from unknown primary hepatocellular carcinoma

We report a 61-year-old male smoker who was admitted to our hospital for treatment of a moderately growing tumour on the right anterolateral chest wall causing chest pain during coughing. Chest computed tomography and magnetic resonance imaging showed a 55 x 50 mm inhomogeneous mass around the 4th rib but not penetrating the subcutis and lung. Neither a preoperative technetium scintigraphy nor a needle biopsy revealed the primary nature of the tumour. The patient was treated with en bloc resection and partial resection of the adjacent 3rd and 4th rib. The frozen section diagnosis confirmed a metastasis from a primary hepatocellular carcinoma.     

Myocardial perfusion imaging: clinical experience and recent progress in radionuclide scintigraphy and magnetic resonance imaging

In the past 20 years, radionuclide scintigraphy has proven to be a sensitive clinical tool in the assessment of myocardial perfusion abnormalities. Magnetic resonance imaging may also be used to study myocardial perfusion, but its potential value still has to emerge in the clinical setting. This review addresses the potential and achievements of both methods in clinical cardiology.