Disposable silicon-based all-in-one micro-qPCR for rapid on-site detection of pathogens

cycle. Using TriSilix, we also detect the cDNA from SARS-CoV-2 (1 pg) with high specificity against SARS-CoV (2003)

Disposable sensors in diagnostics, food and environmental monitoring

Disposable sensors are low‐cost and easy‐to‐use sensing devices intended for short‐term or rapid single‐point measurements. The growing demand for fast, accessible, and reliable information in a vastly connected world makes disposable sensors increasingly important. The areas of application for such devices are numerous, ranging from pharmaceutical, agricultural, environmental, forensic, and food sciences to wearables and clinical diagnostics, especially in resource‐limited settings. The capabilities of disposable sensors can extend beyond measuring traditional physical quantities (for example, temperature or pressure); they can provide critical chemical and biological information (chemo‐ and biosensors) that can be digitized and made available to users and centralized/decentralized facilities for data storage, remotely. These features could pave the way for new classes of low‐cost systems for health, food, and environmental monitoring that can democratize sensing across the globe. Here, a brief insight into the materials and basics of sensors (methods of transduction, molecular recognition, and amplification) is provided followed by a comprehensive and critical overview of the disposable sensors currently used for medical diagnostics, food, and environmental analysis. Finally, views on how the field of disposable sensing devices will continue its evolution are discussed, including the future trends, challenges, and opportunities

Cortisol Responses to Mental Stress and the Progression of Coronary Artery Calcification in Healthy Men and Women

Background: Psychosocial stress is a risk factor for coronary heart disease (CHD). The mechanisms are incompletely understood, although dysfunction of the hypothalamic pituitary adrenal (HPA) axis might be involved. We examined the association between cortisol responses to laboratory-induced mental stress and the progression of coronary artery calcification (CAC). Methods and Results: Participants were 466 healthy men and women (mean age = 62.7±5.6 yrs), without history or objective signs of CHD, drawn from the Whitehall II epidemiological cohort. At the baseline assessment salivary cortisol was measured in response to mental stressors, consisting of a 5-min Stroop task and a 5-min mirror tracing task. CAC was measured at baseline and at 3 years follow up using electron beam computed tomography. CAC progression was defined as an increase >10 Agatston units between baseline and follow up. 38.2% of the sample demonstrated CAC progression over the 3 years follow up. There was considerable variation in the cortisol stress response, with approximately 40% of the sample responding to the stress tasks with an increase in cortisol of at least 1 mmol/l. There was an association between cortisol stress reactivity (per SD) and CAC progression (odds ratio = 1.27, 95% CI, 1.02–1.60) after adjustments for age, sex, pre-stress cortisol, employment grade, smoking, resting systolic BP, fibrinogen, body mass index, and use of statins. There was no association between systolic blood pressure reactivity and CAC progression (odds ratio per SD increase = 1.03, 95% CI, 0.85–1.24). Other independent predictors of CAC progression included age, male sex, smoking, resting systolic blood pressure, and fibrinogen. Conclusion: Results demonstrate an association between heightened cortisol reactivity to stress and CAC progression. These data support the notion that cortisol reactivity, an index of HPA function, is one of the possible mechanisms through which psychosocial stress may influence the risk of CHD

Ventilatory disorders in heart failure

Introduction: Chronic obstructive pulmonary disease (COPD), heart failure (HF) or both syndromes are the most common reasons for dyspnea in the elderly. Currently there is no standard to diagnose COPD and multiple definitions (fixed ratio [GOLD], lower limit of normal [LLN]) are discussed. Further, HF may impact on the results of pulmonary function testing (PFT), impeding proper diagnosis of pulmonary diseases. In this thesis, we aimed to elucidate important difficulties in diagnosing and grading of COPD in HF and to characterize other ventilatory disorders in HF. Methods: The results are based on two prospective cohort studies: the “UHFO-COPD-study” (N=405 patients with a general practitioner’s diagnosis of COPD) and the “INH-Study” (N=619 patients with HF with reduced ejection fraction [HFrEF]). Results: First, the diagnostic accuracy of the GOLD-COPD-definition and of three LLN-definitions were compared with the consensus diagnosis of an expert-panel, that used all available clinical and diagnostic information in the UHFO-COPD-study. Compared to the LLN-definitions, GOLD had the smallest number of misdiagnosis (‘GOLD-COPD’ 28%, three LLN-definitions 46%, 39%, and 40%), and was therefore used for all following studies to define COPD. Serially measured PFT results and COPD prevalence rates were compared in N=272 patients hospitalized for decompensated HFrEF in the INH-study. COPD, defined as non-reversible central airways obstruction (CAO) was present in 51/272(19%) of patients during hospitalization, but only in 24/51(47%) diagnosis could be reconfirmed 6 months later. Hyperinflation - a feature generally seen in COPD but not in HF –, predicted persisting COPD. Thus, a diagnosis of COPD in HF requires serial PFT under stable conditions or PFT including bodyplethysmography. Patients of the UHFO-COPD and the INH-study were divided into three groups: 1. HF only (N=557) 2. COPD only (N=108), and 3. HF+COPD (N=194). In patients with HF only, 25% exhibited forced expiratory volume in 1 sec (FEV1) levels of <80%. Compared with COPD only, patients with HF+COPD had higher levels of FEV1/forced vital capacity (FVC) and lower total lung capacity, but comparable FEV1-levels and thus similar distributions of GOLD stages I-IV in both groups (24/56/19/4% vs 31/50/19/1%, P=NS). Intake of beta-2-mimetics was associated with an increased mortality risk in patients with HF+COPD. Thus, classifying COPD based on FEV1 levels in HF may overrate obstruction severity, and provoke unnecessary and potentially harmful therapy. In HF, small airways obstruction (SAO) defined as maximum expiratory flow at 50% of FVC<60% of predicted is more common than CAO, but the prognostic relevance is unclear. In 585 patients with stable HFrEF, SAO was more common (N=226, 39%) as CAO (N=88, 15%), but had similar predictive utility. Further in N=162 patients with exclusion of COPD and without previously known HF, SAO was able to uncover HF and predict future pulmonary events as hospitalizations for pulmonary reasons and pneumonia. Conclusions: In patients with HF, SAO and CAO are common and both associated with increased mortality risk. Diagnosing and severity grading of COPD in HF is hampered for different reasons. Adding bodyplethysmography to PFT and performing PFT under stable conditions may increase accuracy of COPD diagnosis in HF