Genomic monitoring of SARS-CoV-2 variants using sentinel SARI hospital surveillance.

Background: To support the COVID-19 pandemic response, many countries, including Belgium, implemented baseline genomic surveillance (BGS) programs aiming to early detect and characterize new SARS-CoV-2 variants. In parallel, Belgium maintained a sentinel network of six hospitals that samples patients with severe acute respiratory infections (SARI) and integrated SARS-CoV-2 detection within a broader range of respiratory pathogens. We evaluate the ability of the SARI surveillance to monitor general trends and early signals of viral genetic evolution of SARS-CoV-2 and compare it with the BGS as a reference model.

Nationwide Harmonization Effort for Semi-Quantitative Reporting of SARS-CoV-2 PCR Test Results in Belgium.

From early 2020, a high demand for SARS-CoV-2 tests was driven by several testing indications, including asymptomatic cases, resulting in the massive roll-out of PCR assays to combat the pandemic. Considering the dynamic of viral shedding during the course of infection, the demand to report cycle threshold (Ct) values rapidly emerged. As Ct values can be affected by a number of factors, we considered that harmonization of semi-quantitative PCR results across laboratories would avoid potential divergent interpretations, particularly in the absence of clinical or serological information.

A new perfusion mode of culture for WJ-MSCs expansion in a stirred and online monitored bioreactor.

As a clinical dose requires a minimum of 10 cells per kilogram of patients, it is, therefore, crucial to develop a scalable method of production of Wharton Jelly mesenchymal stem cells (WJ-MSCs) with maintained inner characteristics. Scalable expansion of WJ-MSCs on microcarriers usually found in cell culture, involves specific cell detachment using trypsin and could have harmful effects on cells. In this study, the performance of batch, fed-batch, and perfused-continuous mode of culture were compared.

Quality by design to define critical process parameters for mesenchymal stem cell expansion.

Stem cell-based therapeutic products could be the key to treat the deadliest current pathologies, ranging from neuro-degenerative to respiratory diseases. However, in order to bring these innovative therapeutics to a commercialization stage, reproducible manufacturing of high quality cell products is required. Although advances in cell culture techniques have led to more robust production processes and dramatically accelerated the development of early-phase clinical studies, challenges remain before regulatory approval, particularly to define and implement science-based quality standards (essential pre-requisites for national health agencies).

Immersive Virtual Reality to Restore Natural Long-Range Autocorrelations in Parkinson's Disease Patients' Gait During Treadmill Walking.

Effects of treadmill walking on Parkinson's disease (PD) patients' spatiotemporal gait parameters and stride duration variability, in terms of magnitude [coefficient of variation (CV)] and temporal organization [long range autocorrelations (LRA)], are known. Conversely, effects on PD gait of adding an optic flow during treadmill walking using a virtual reality headset, to get closer to an ecological walk, is unknown. This pilot study aimed to compare PD gait during three conditions: Overground Walking (OW), Treadmill Walking (TW), and immersive Virtual Reality on Treadmill Walking (iVRTW).

Impact of the type of microcarrier and agitation modes on the expansion performances of mesenchymal stem cells derived from umbilical cord.

The present study proposed to compare the impact of agitation mode (static, orbital, and mechanical) on the culture of mesenchymal stem cells extracted from the Wharton's jelly of umbilical cords (WJ-MSC), in a clinical grade culture medium, using human platelet lysate and different xeno-free microcarriers. Attachment, expansion, and detachment performances were characterized by a new dedicated tool of microscopic image posttreatment, allowing an in situ cell counting without detachment step. Results showed that performances in static mode were not necessarily representative of those obtained in dynamic mode.

Development of inducible EIAV-based lentiviral vector packaging and producer cell lines.

Large-scale production of gene therapeutics comprising equine infectious anaemia virus (EIAV) -based lentiviral vectors (LVs) would benefit from the development of producer cell lines enabling the generation of larger quantities of vector than achievable by transient systems. Such cell lines would contain three vector components (Gag/Pol, VSV-G envelope and genome expression constructs). As the vesicular stomatitis virus (VSV-G) envelope protein is cytotoxic, its expression must be regulated.

Financial consequences of hospital-acquired bacteraemia in three Belgian hospitals in 2003 and 2004.

The financial and human costs of hospital-acquired infections are increasingly recognised in many healthcare systems. This study seeks to quantify excess expenditures on hospital-acquired bacteraemia (HAB) in three Belgian general hospitals in 2003 and 2004. Patients with HAB were compared with patients in the same All Patient Refined Diagnosis Related Groups (APR-DRGs) without HAB.

Analysis of factor VIII mediated suppression of lentiviral vector titres.

Effective gene therapy for haemophilia A necessitates a vector system that is not subject to a pre-existing immune response, has adequate coding capacity, gives long-term expression and preferably can target non-dividing cells. Vector systems based on lentiviruses such as equine infectious anaemia virus (EIAV) fulfil these criteria for the delivery of factor VIII (FVIII). We have found that B domain-deleted (BDD) FVIII protein inhibits functional viral particle production when co-expressed with the EIAV vector system.

[Clinical case of the month: clostridium difficile colitis].

A 55-year-old patient with mant e cels underwent a cytotoxic chemotherapy (D.H.A.

National epidemiologic surveys of Enterobacter aerogenes in Belgian hospitals from 1996 to 1998.

Two national surveys were conducted to describe the incidence and prevalence of Enterobacter aerogenes in 21 Belgian hospitals in 1996 and 1997 and to characterize the genotypic diversity and the antimicrobial resistance profiles of clinical strains of E. aerogenes isolated from hospitalized patients in Belgium in 1997 and 1998. Twenty-nine hospitals collected 10 isolates of E.

Early identification of Mycobacterium tuberculosis and Mycobacterium avium using the polymerase chain reaction on samples positive by a rapid commercial culture system.

A combination of two methods -- a rapid culture method [Mycobacteria Growth Indicator Tube (MGIT); Becton-Dickinson, USA] and a double polymerase chain reaction (PCR) assay -- was assessed for the detection and identification of Mycobacterium tuberculosis and Mycobacterium avium from clinical samples. The aim of the study was to evaluate the ability of the system to offer rapid and accurate diagnosis of mycobacterial infections. After decontamination, clinical samples (n = 554) were stained and cultured in parallel on solid media and in MGITs following standard procedures.