This report presents the highlights of the 7th European Meeting on Molecular Diagnostics held in Scheveningen, The Hague, The Netherlands, 12-14 October 2011. The areas covered included molecular diagnostics applications in medical microbiology, virology, pathology, hemato-oncology,clinical genetics and forensics. Novel real-time amplification approaches, novel diagnostic applications and new technologies, such as next-generation sequencing, PCR lectrospray-ionization TOF mass spectrometry and techniques based on the detection of proteins or other molecules, were discussed. Furthermore, diagnostic companies presented their future visions for molecular diagnostics in human healthcare.
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To accelerate differentiation between Staphylococcus aureus and Coagulase Negative Staphylococci (CNS), this study aimed to compare six different DNA extraction methods from 2 commonly used blood culture materials, i.e. BACTEC and Bact/ALERT. Furthermore, we analyzed the effect of reduced blood culture times for detection of Staphylococci directly from blood culture material. A real-time PCR duplex assay was used to compare 6 different DNA isolation protocols on two different blood culture systems. Negative blood culture material was spiked with MRSA. Bacterial DNA was isolated with: automated extractor EasyMAG (3 protocols), automated extractor MagNA Pure LC (LC Microbiology Kit MGrade), a manual kit MolYsis Plus, and a combination between MolYsis Plus and the EasyMAG. The most optimal isolation method was used to evaluate reduced bacterial culture times. Bacterial DNA isolation with the MolYsis Plus kit in combination with the specific B protocol on the EasyMAG resulted in the most sensitive detection of S.aureus, with a detection limit of 10 CFU/ml, in Bact/ALERT material, whereas using BACTEC resulted in a detection limit of 100 CFU/ml. An initial S.aureus load of 1 CFU/ml blood can be detected after 5 hours of culture in Bact/ALERT3D by combining the sensitive isolation method and the tuf LightCycler assay.
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Inulin is a soluble dietary fibre, also classified as a prebiotic, extracted from chicory roots. The present study aimed to determine the effect of consumption of native chicory inulin on the stool frequency of middle-aged to older adults (40–75 years old) with uncomfortably but not clinically relevant low stool frequency, specified as two to four days without bowel movements per week. Two randomised, double blind, placebo-controlled crossover trials were conducted using similar protocols in differing populations. Trial A was conducted in Amsterdam, The Netherlands and subsequently Trial B was conducted in Newcastle, United Kingdom. Both trials involved supplementation for 5 weeks with 10 g per day of inulin or placebo, a washout period of 2 weeks, and then crossed over to receive the other treatment. In Trial B, faecal gut microbiota composition was assessed using 16S rRNA gene sequencing. In Trial A, which 10 volunteers completed, the stool frequency was significantly increased to an average 4.9 ± 0.23 (SEM) times per week during inulin periods versus 3.6 ± 0.25 in the periods with placebo (p = 0.01). In contrast, in Trial B which 20 volunteers completed, there was no significant effect of the inulin on stool frequency (7.5 ± 2.1 times per week with inulin, 8.1 ± 3.0 with placebo, p = 0.35). However, many subjects in Trial B had a stool frequency >5 per week also for the placebo period, in breach of the inclusion criteria. Combining the data of 16 low stool frequency subjects from Trials A and B showed a significant effect of inulin to increase stool frequency from 4.1 to 5.0 per week (p = 0.032). Regarding secondary outcomes, stool consistency was significantly softer with inulin treatment compared to placebo periods, it increased 0.29 on the Bristol stool scale (p = 0.008) when data from all subjects of Trials A and B were combined. No other differences in bowel habit parameters due to inulin consumption were significant. None of the differences in specific bacterial abundance, alpha or beta diversity were significant, however the trends were in directions consistent with published studies on other types of inulin. We conclude that 10 g per day of native chicory inulin can increase stool frequency in subjects with low stool frequency.
MULTIFILE
To treat microbial infections, antibiotics are life-saving but the increasing antimicrobial resistance is a World-wide problem. Therefore, there is a great need for novel antimicrobial substances. Fruit and flower anthocyanins have been recognized as promising alternatives to traditional antibiotics. How-ever, for future application as innovative alternative antibiotics, the full potential of anthocyanins should be further investigated. The antimicrobial potential of anthocyanin mixtures against different bacterial species has been demonstrated in literature. Preliminary experiments performed by our laboratories, using grape, rose and red cabbage anthocyanins against S. aureus and E. coli confirmed the antimicrobial potential of these substances. Hundreds of different anthocyanin entities have been described. However, which of these entities hold antimicrobial effects is currently unknown. Our preliminary data show that an-thocyanins extracted from grape, rose and red cabbage contain different collections of anthocyanin entities with differential antimicrobial efficacies. Our focus is on the extraction and characterization of anthocyanins from various crop residues. Grape peels are residues in the production of wine, while red rose and tulip leaves are residues in the production of tulip bulbs and regular horticulture. The presence of high-grade substances for pharmacological purposes in these crops may provide an innovative strategy to add value to other-wise invaluable crop residues. This project will be performed by the collaborative effort of our institute together with the Medi-cal Microbiology department of the University Medical Center Groningen (UMCG), 'Wijnstaete', a small-scale wine-producer (Lemelerveld) and Imenz Bioengineering (Groningen), a company that develops processes to improve the production of biobased chemicals from waste products. Within this project, we will focus on the antimicrobial efficacy of anthocyanin-mixtures from sources that are abundantly and locally available as a residual waste product. The project is part of a larger re-search effect to further characterize, modify and study the antimicrobial effects of specific anthocy-anin entities.
What if living organisms communicated signals from the environment to us and thereby offered a sustainable alternative to electronic sensors? Within the field of biodesign, designers and scientists are collaborating with living organisms to produce new materials with ecological benefits. The company Hoekmine, in collaboration with designers, has been researching the potential of flavobacteria for producing sustainable colorants to be applied on everyday products. These non-harmful bacteria can change their form, texture and iridescent color in response to diverse environmental factors, such as humidity and temperature. Here, billions of cells are sensing and integrating the results as color. Therefore, Hoekmine envisions biosensors, which would minimize the use of increasingly demanded electronic sensors, and thus, the implementation of scarce and toxic materials. Developing a living sensor by hosting flavobacteria in a biobased and biodegradable flexible material offers opportunities for sustainable alternatives to electronic sensors. Aiming to take this concept to the next level, we propose a research collaboration between Avans, Hoekmine and a company specialized in biobased and biodegradable labels, Bio4Life. Together with this interdisciplinary team, we aim to bridge microbiology and embodiment design, and contribute to the development of a circular economy where digital technology and organic systems merge in the design of Living Circular Labels (LCLs). Throughout the project we will use an iterative approach between designing and testing LCLs that host living flavobacteria and additionally, methods for the end user to activate the bacteria’s growth at a given time.
Antimicrobial Resistance (AMR), the ability of micro-organisms to resist antibiotics, is associated with ~4.9 million deaths globally, reported in 2022. In the EU alone, more than 35.000 people die from antimicrobial-resistant infections annually, resulting in loss of life as well as €1.5Bn/year in healthcare costs and productivity losses. Rapid diagnostics tests are needed, current testing takes between 24 hours to a few days (for slow growing microorganisms), delaying patient treatment and severely impacting treatment outcomes. SoundCell BV have developed a technique (TRL5), for real-time detection of bacteria's viability in the presence of antibiotics. Nano-mechanical vibration of an ultrathin graphene sheet correlates to viability of bacteria immobilized on this sheet. Bacterial motion is transferred to this sheet, and movement of this sheet is tracked via a high-speed laser. Living bacteria produce a strong signal, which diminishes when antibiotics kill them. Unaffected by growth rates, results are achieved in one hour with this technique. This technology opens up possibility for rapid diagnostics of antibiotic resistance in patients with infections of slow growing pathogens (such as mycobacteria and yeast). In such cases the time to result is slowest, significantly delaying effective patient treatment. We aim to validate this technique in our clinical microbiology laboratory.
