Multiplex Portable Biosensor for Bacteria Detection.

An advanced, cost-effective, and portable DNA biosensor capable of detecting multiple bacteria simultaneously has been developed. The biosensor comprises a fast and inexpensive potentiostat that controls the applied potential to a screen-printed electrochemical array platform functionalized with MoS2 flakes and bacterial DNA probes. The current response obtained by à la carte thionine functionalized carbon nanodots (Ty-CDs) is monitored as an electrochemical indicator of the hybridization event. The design of the potentiostat prioritizes achieving an optimal signal-to-noise ratio and incorporates a user-friendly interface compatible with various devices, including computers, mobile phones, and tablets. The device is compact, lightweight, and manufactured at a low cost. The key components of the potentiostat include a data acquisition board capable of analyzing multiple samples simultaneously and a controller board. The results of this study confirm the ability of the multiplex portable biosensor to successfully detect specific bacterial DNA sequences, demonstrating its reliability and superior performance compared with a traditional, more complex, and laboratory-oriented potentiostat.

Determinants of the Cost-Effectiveness of Telemedicine: Systematic Screening and Quantitative Analysis of the Literature.

Background and Objectives: Telemedicine holds the promise of increasing access-to-care at a lower cost. Yet, for years, the evidence of telemedicine's cost-effectiveness was scarce. Faced with a rapidly expanding literature, we conduct both manual and systematic selection of the literature, and analyzed the data to determine: (1) the characteristics of economic evaluations of telemedicine, and (2) the determinants of economically efficient telemedicine interventions. Methods: We reviewed all published economic evaluations of telemedicine in Cochrane, Embase, and Pubmed from 2008 to 2018. Articles were screened by two researchers first on title and abstract (Stage 1), then on full article (Stage 2), (protocol available on PROSPERO, ref. CRD42019143032). We proposed an alternative method for screening articles using machine learning based on textual classification and compared these two approaches. We constructed an exclusive dataset on the characteristics of the selected articles and enriched it using OECD data at the country level. We identified the determinants of efficient telemedicine interventions using multiple logit models. Results and Conclusion: We included 156 articles out of 2,639. Most economic studies of our sample regard telemonitoring. A majority (73.7%) of studies found that telemedicine intervention is efficient, regardless of the medical domain. Articles with higher standards of economic evaluation (cost-effectiveness analysis, randomized trials with high sample size) were less likely to report an efficient intervention. We found no effect of the publication year, signifying that the nature of the evidence has not changed over time.

Paving the way to point of care (POC) devices for SARS-CoV-2 detection.

In this work we present a powerful, affordable, and portable biosensor to develop Point of care (POC) SARS-CoV-2 virus detection. It is constructed from a fast, low cost, portable and electronically automatized potentiostat that controls the potential applied to a disposable screen-printed electrochemical platform and the current response. The potentiostat was designed to get the best signal-to-noise ratio, a very simple user interface offering the possibility to be used by any device (computer, mobile phone or tablet), to have a small and portable size, and a cheap manufacturing cost. Furthermore, the device includes as main components, a data acquisition board, a controller board and a hybridization chamber with a final size of 10 × 8 × 4 cm. The device has been tested by detecting specific SARS-CoV-2 virus sequences, reaching a detection limit of 22.1 fM. Results agree well with those obtained using a conventional potentiostat, which validate the device and pave the way to the development of POC biosensors. In this sense, the device has finally applied to directly detect the presence of the virus in nasopharyngeal samples of COVID-19 patients and results confirm its utility for the rapid detection infected samples avoiding any amplification process.

Incidence rate and risk factors for loss to follow-up in HIV-infected patients from five French clinical centres in Northern France - January 1997 to December 2006.

BACKGROUND: Our goal was to determine the incidence rate and risk factors for loss to follow-up (LTFU) of HIV-infected patients in Northern France. METHODS: We estimated the incidence rate of LTFU in 1,007 HIV-infected patients under care from January 1997 to December 2006. We then investigated potential risk factors for LTFU at inclusion and during follow-up. RESULTS: The incidence of LTFU was estimated to be 3.5 per 100 person-years. Risk factors for LTFU at enrolment in a multivariate Cox model were age <30 years (hazard ratio [HR] 1.66 versus >40 years, 95% confidence interval [CI] 1.04-2.64), transmission by injection drug use (HR 5.26 versus men who have sex with men, 95% CI 2.90-9.52), no phone number provided (HR 5.4, 95% CI 3.6-8.2), no primary care physician (HR 2.10, 95% CI 1.25-3.52) and sub-Saharan African origin (HR 2.09, 95% CI 1.36-3.22). Patients with CD4(+) T-cell counts <200 cells/mm(3) (HR 0.49 versus >/=350 cells/mm(3), 95% CI 0.32-0.76) and 200-349 cells/mm(3) at baseline (HR 0.63 versus >/=350 cells/mm(3), 95% CI 0.41-0.98) had a decreased risk of LTFU. During follow-up, the risk of LTFU increased when the most recent CD4(+) T-cell count was <200 cells/mm(3) (HR 2.06, 95% CI 1.16-3.66), the patient was not on highly active antiretroviral therapy (HAART; HR 4.20, 95% CI 2.66-6.61) and the patient was on HAART but had a detectable viral load (HR 1.92, 95% CI 1.19-3.01). CONCLUSIONS: Our findings will help clinicians recognize patients who require additional support for retention in care, including younger patients, injection drug users, people of sub-Saharan African origin, patients who are healthier at enrolment and patients who do not adhere to HAART during follow-up.

Characteristics of and outcomes in HIV-infected patients who return to care after loss to follow-up.

The objective of this study was to evaluate the characteristics of and outcomes in HIV-infected patients who returned to care after loss to follow-up (LTFU) in Northern France, between 1997 and 2006. Among the 1007 patients who were followed, 135 patients (13.4%) were LTFU during the study period. Of these 135, 74 (54.8%) returned to care after LTFU. The median duration of LTFU was 19 months. Upon returning to care, 33 out of 74 patients (44.6%) had CD4 cell counts less than 200/mm and/or AIDS. Patients who returned to care after LTFU were five times more likely to die than patients who attended clinic regularly.