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Review of: Chiara Zampieri, Martina Piperno & Bart Van den Bossche (eds.), Modern Etruscans. Close Encounters with a Distant Past, Leuven, Leuven University Press, 2023, 187 p., ISBN: 9789462703797, € 30,00 (also available in Open Access).

Abstract Background Blood plasma, one of the most studied liquid biopsies, contains various molecules that have biomarker potential for cancer detection, including cell-free DNA (cfDNA) and cell-free RNA (cfRNA). As the vast majority of cell-free nucleic acids in circulation are non-cancerous, a laboratory workflow with a high detection sensitivity of tumor-derived nucleic acids is a prerequisite for precision oncology. One way to meet this requirement is by the combined analysis of cfDNA and cfRNA from the same liquid biopsy sample. So far, no study has systematically compared the performance of cfDNA and cfRNA co-purification to increase sensitivity. Results First, we set up a framework using digital PCR (dPCR) technology to quantify cfDNA and cfRNA from human blood plasma in order to compare cfDNA/cfRNA co-purification kit performance. To that end, we optimized two dPCR duplex assays, designed to quantify both cfDNA and cfRNA with the same assays, by ensuring that primers and probes are located within a highly abundant exon. Next, we applied our optimized workflow to evaluate the co-purification performance of two manual and two semi-automated methods over a range of plasma input volumes (0.06–4 mL). Some kits result in higher nucleic acid concentrations in the eluate, while consuming only half of the plasma volume. The combined nucleic acid quantification systematically results in higher nucleic acid concentrations as compared to a parallel quantification of cfDNA and cfRNA in the eluate. Conclusions We provide a framework to evaluate the performance of cfDNA/cfRNA co-purification kits and have tested two manual and two semi-automated co-purification kits in function of the available plasma input amount and the intended use of the nucleic acid eluate. We demonstrate that the combined quantification of cfDNA and cfRNA has a benefit compared to separate quantification. We foresee that the results of this study are instrumental for clinical applications to help increase mutation detection sensitivity, allowing improved disease detection and monitoring.

Abstract Background The microbiome of many insects consists of a diverse community of microorganisms that can play critical roles in the functioning and overall health of their hosts. Although the microbial communities of insects have been studied thoroughly over the past decade, little is still known about how biotic interactions affect the microbial community structure in and on the bodies of insects. In insects that are attacked by parasites or parasitoids, it can be expected that the microbiome of the host insect is affected by the presence of these parasitic organisms that develop in close association with their host. In this study, we used high-throughput amplicon sequencing targeting both bacteria and fungi to test the hypothesis that parasitism by the endoparasitoid Cotesia glomerata affected the microbiome of its host Pieris brassicae. Healthy and parasitized caterpillars were collected from both natural populations and a laboratory culture. Results Significant differences in bacterial community structure were found between field-collected caterpillars and laboratory-reared caterpillars, and between the external and the internal microbiome of the caterpillars. Parasitism significantly altered the internal microbiome of caterpillars, but not the external microbiome. The internal microbiome of all parasitized caterpillars and of the parasitoid larvae in the caterpillar hosts was dominated by a Wolbachia strain, which was completely absent in healthy caterpillars, suggesting that the strain was transferred to the caterpillars during oviposition by the parasitoids. Conclusion We conclude that biotic interactions such as parasitism have pronounced effects on the microbiome of an insect host and possibly affect interactions with higher-order insects.

There is increasing evidence that host–parasitoid interactions can have a pronounced impact on the microbiome of host insects, but it is unclear to what extent this is caused by the host and/or parasitoid. Here, we compared the internal and external microbiome of caterpillars of Pieris brassicae and Pieris rapae parasitized by Cotesia glomerata or Cotesia rubecula with nonparasitized caterpillars. Additionally, we investigated the internal and external microbiome of the parasitoid larvae. Both internal and external bacterial densities were significantly higher for P. brassicae than P. rapae , while no differences were found between parasitized and nonparasitized caterpillars. In contrast, parasitism significantly affected the composition of the internal and external microbiome of the caterpillars and the parasitoid larvae, but the effects were dependent on the host and parasitoid species. Irrespective of host species, a Wolbachia species was exclusively found inside caterpillars parasitized by C. glomerata , as well as in the corresponding developing parasitoid larvae. Similarly, a Nosema species was abundantly present inside parasitized caterpillars and the parasitoid larvae, but this was independent of the host and the parasitoid species. We conclude that parasitism has pronounced effects on host microbiomes, but the effects depend on both the host and parasitoid species. [ABSTRACT FROM AUTHOR]

Background and Aims: The management of chronic inflammatory bowel diseases in youth is challenging. We aimed to determine health literacy (HL), quality of life (QoL) and clinical outcomes in young adults from the BELgian CROhn's disease registry (BELCRO) in comparison to type 1 diabetes mellitus (DM) as a control.Methods: In this prospective and observational study, young adults with Crohn's disease (CD) diagnosed < 18 years and with > 5 years disease duration and a comparable group of patients with DM completed validated HL, QoL and work productivity and activity impairment questionnaires (HLS-EU-Q16, EQ-5D-5L and WPAI). HL was scored as sufficient (13–16), problematic (9–12) or inadequate (0–8). QoL was dichotomized into “no problems” (EQ-5D level 1) or “problems” (EQ-5D levels 2 to 5). Non-parametric (Mann-Whitney U) analyses and Spearman correlations were performed.Results: A total of 52 CD (median [IQR] age of 25.0 [23.8-27.0], 64% male) and 50 DM (age 20.0 [19.0-22.0], 50% male) patients were included. HL was 14.0 [11.0-16.0] for CD and 14.0 [11.3-14.8] for DM (p = 0.6) with similar proportions of sufficient (60 vs. 68%, p = 0.4), problematic (34 vs. 26%, p = 0.3) and inadequate HL (both 6%, p = 1). Although QoL was comparable for CD and DM (77.0 [68.8-82.0] vs. 75.0 [65.0-80.0] %, p =0.4), CD had a trend for higher pain/discomfort (50 vs. 32%, p = 0.06). HL and QoL correlated in CD (r = 0.6, p < 0.001) and DM patients (r = 0.6, p < 0.001). Fewer CD patients with recent hospitalization/surgery had sufficient HL (31 vs. 69%, p = 0.01) and had lower QoL (70.0 [60.0-77.0] vs. 80.0 [70.0-85.0], p = 0.04) compared to those without.Conclusions: Selected young Belgian adults suffering from CD for >5 years have similar and sufficient HL compared to DM patients. However, CD patients requiring hospitalization/surgery have lower HL, which indicates the need for targeted educational programs.

Currently, one of the most important challenges is to provide sufficient and affordable food and energy for a fast-growing world population, alongside preserving natural habitats and maintaining biodiversity. About 35% of the global food production depends on animals for pollination. In recent years, an alarming worldwide decline in pollinators has been reported, putting our food production under additional pressure. Therefore, there is an urgent need to find sustainable ways to ensure this crucial ecosystem service. Recent studies have shown that floral nectar is generally colonized by microorganisms, specifically yeasts and bacteria, which may alter nectar chemistry and enhance attraction of pollinators. In this study, we investigated changes in pollinator foraging behavior and pollination success in European pear (Pyrus communis L.) cultivars 'Regal Red' and 'Sweet Sensation' (red sports of 'Doyenné de Comice') after flower inoculation with the typical nectar-inhabiting microorganisms Metschnikowia reukaufii and Acinetobacter nectaris, and a combination of both. Pollination success was monitored by measuring the number of flower visits, fruit set and seed set in two consecutive years, 2019 and 2020. Results revealed that application of a mixture of M. reukaufii and A. nectaris resulted in significantly higher visitation rates of honeybees and hoverflies. By contrast, no effects on flower visits were found when yeasts and bacteria were applied separately. Fruit set and seed set were not significantly affected by any of the inoculation treatments. The only factors affecting fruit set were initial number of flower clusters on the trees and the year. The absence of treatment effects can most likely be attributed to the fact that pollination was not a limiting factor for fruit set in our experiments. Altogether, our results show that inoculation of flowers with nectar microbes can modify pollinator foraging patterns, but did not lead to increased pollination success under the conditions tested.

This review investigates the performance and the feasibility of the integration of an algal reactor in recirculating aquaculture systems (RAS). The number of studies related to this topic is limited, despite the apparent benefit of algae that can assimilate part of the inorganic waste in RAS. We identified two major challenges related to algal integration in RAS: first, the practical feasibility for improving nitrogen removal performance by algae in RAS; second, the economic feasibility of integrating an algal reactor in RAS. The main factors that determine high algal nitrogen removal rates are light and hydraulic retention time (HRT). Besides these factors, nitrogen-loading rates and RAS configuration could be important to ensure algal performance in nitrogen removal. Since nitrogen removal rate by algae is determined by HRT, this will affect the size (area or volume) of the algal reactor due to the time required for nutrient uptake by algae and large surface area needed to capture enough light. Constraints related to design, space, light capture, and reactor management could incur additional cost for aquaculture production. However, the increased purification of RAS wastewater could reduce the cost of water discharge in places where this is subject to levees. We believe that an improved understanding of how to manage the algal reactor and technological advancement of culturing algae, such as improved algal reactor design and low-cost artificial light, will increase the practical and economic feasibility of algal integration in RAS, thus improving the potential of mass cultivation of algae in RAS.

To assess the potential for improving sustainability and efficiency in an important Vietnamese finfish culture, we quantified sustainability indicators for 2 downstream and 2 upstream 3 to 4 m deep ponds for striped catfish Pangasianodon hypophthalmus (Sauvage, 1878) production along the Mekong River, Vietnam. The resources used per kg fish produced were (downstream vs. upstream): 2.8 vs. 7.1 m3 water, 0.04 vs. 0.14 kWh energy, 0.06 vs. 0.11 h human labour and 0.06 vs. 0.15 g antibiotics (p < 0.05). The feed conversion ratio (kg feed dry matter per kg fish wet weight) was 1.50 vs. 1.65 and feed dry matter utilization efficiency was similar (28 vs. 30%) for both types of ponds (p > 0.05). Nitrogen and phosphorus utilization efficiencies were 44 vs. 40% for nitrogen (p < 0.05) and 17.7 vs. 17.6% for phosphorus (p > 0.05). An advantage of production in deep ponds is the breakdown of organic matter through denitrification and fermentation. Based on the difference between feed input and monitored outputs and sinks, an estimated 29–37% of dry matter volatilized as CO2 and 30–34% of nitrogen was lost as N2. A major disadvantage of the deep pond production system is its dependency on water exchange with the Mekong River, resulting in low biosecurity, which is aggravated by the lack of availability of disease-free fingerlings. Dealing with disease caused farmers to apply suboptimal feeding rations and to lengthen the culture period. Developing (semi-)closed systems that adopt elements from recirculation technology could improve both culture performance and sustainability.

Incorporation of microalgae in recirculating aquaculture systems (RAS) would absorb the inorganic nitrogen and phosphorus, thus potentially contributing to water purification. Immobilization or entrapment of microalgal cells in spherical gels is a potential method to incorporate microalgae in the RAS. Filamentous microalgae are presumed to suit the immobilization technique because the gels can serve as substrates for the microalgae to attach. In the first experiment of this study, growth and nitrogen uptake of Stigeoclonium nanum, a filamentous microalga, was compared when cultured using an immobilization technique or in a normal suspension. In the second experiment, immobilized S. nanum was cultured in 4 media with different total ammonia nitrogen (TAN) and nitrate-nitrogen (NO3-N) concentrations. The results showed a significantly higher algal growth and TAN removal by S. nanum immobilized in alginate than for S. nanum in free suspension culture. When both TAN and NO3-N were added to the culture medium, the uptake of TAN by immobilized S. nanum was significantly more efficient than NO3-N uptake. Our results indicated that S. nanum was able to grow immobilized in a medium, exhibiting a higher growth and TAN uptake than when the algae were in free suspension. S. nanum preferred ammonium over nitrate, which is suitable for RAS that require removal of the total ammonia which is produced by fish and by organic decomposition in the system.

Abstract Production of many agricultural crops and fruits strongly depends on pollinators. For instance, pome fruits such as apple and pear are highly dependent on pollination for fruit set, fruit quality, and yield. Nectar is often inhabited by microbes, most often yeasts and bacteria, which may change nectar quality and therefore also affect plant–pollinator interactions. Here, we used high‐throughput 16S ribosomal RNA gene amplicon sequencing to investigate the temporal and spatial variation in bacterial communities in floral nectar of apple and pear. We sampled 15 apple (Malus x domestica Borkh.) and 15 pear (Pyrus communis L.) orchards distributed over the eastern part of Belgium over a timespan of seven days. Nectar bacterial community composition differed strongly among fruit species. Nectar of pear was dominated by Actinobacteria, followed by Proteobacteria and Firmicutes. Apple nectar was strongly enriched in Bacteroidetes, a phylum which until now has been found to be rarely associated with floral nectar. Nectar was dominated by only a few bacterial species, with Brevibacterium (Actinobacteria) and Undibacterium (Proteobacteria) as the most abundant bacteria in pear and apple nectar, respectively. Bacterial richness and diversity were found to fluctuate during flowering, likely due to changing environmental conditions. Additionally, spatial structure in nectar bacterial community composition was found in apple orchards, while this was not the case for pear. Differences in nectar bacterial communities between apple and pear nectar may differently affect the chemical and nutritional composition of the nectar, influencing pollinator attraction and visitation, and thus pollination efficacy in general.