4 research outputs found
A straightforward molecular strategy to retrospectively investigate the spread of SARS-CoV-2 VOC202012/01 B.1.1.7 variant.
The spread of new SARS-CoV-2 variants represents a serious threat worldwide, thus rapid and cost-effective methods are required for their identification. Since November 2020, the TaqPath COVID-19 assay (Thermo Fisher Scientific) has been used to identify viral strains of the new lineage B.1.1.7, since it fails to detect the S-gene with the â69/70 deletion. Here, we proposed S-gene mutations screening with the Allplex SARS-CoV-2 assay (Seegene), another widely used RT-PCR test that targets Sarbecovirus E, SARS-CoV-2 N, and RdRp/S genes. Accordingly, we evaluated the S gene amplification curve pattern compared to those of the other genes. Exploiting an Allplex assay-generated dataset, we screened 663 RT-PCR digital records, including all SARS-CoV-2 respiratory samples tested in our laboratory with the Allplex assay between January 1st and February 25th, 2021. This approach enabled us to detect 64 samples with peculiar non-sigmoidal amplification curves. Sequencing a selected group of 4 RNA viral genomes demonstrated that those curves were associated with B.1.1.7 variant strains. Our results strongly suggest that B.1.1.7 variant spread has begun in this area at least since January and imply the potential of these analytical methods to track and characterize the spread of B.1.1.7 strains in those areas where Allplex SARS-CoV-2 datasets have been previously recorded
Metaproteomic assessment of gut microbial and host functional perturbations in Helicobacter pylori-infected patients subjected to an antimicrobial protocol
ABSTRACTThe impact of therapeutic interventions on the human gut microbiota (GM) is a clinical issue of paramount interest given the strong interconnection between microbial dynamics and human health. Orally administered antibiotics are known to reduce GM biomass and modify GM taxonomic profile. However, the impact of antimicrobial therapies on GM functions and biochemical pathways has scarcely been studied. Here, we characterized the fecal metaproteome of 10 Helicobacter pylori-infected patients before (T0) and after 10âdays (T1) of a successful quadruple therapy (bismuth, tetracycline, metronidazole, and rabeprazole) and 30âdays after therapy cessation (T2), to investigate how GM and host functions change during the eradication and healing processes. At T1, the abundance ratio between microbial and host proteins was reversed compared with that at T0 and T2. Several pathobionts (including Klebsiella, Proteus, Enterococcus, Muribaculum, and Enterocloster) were increased at T1. Therapy reshaped the relative contributions of the functions required to produce acetate, propionate, and butyrate. Proteins related to the uptake and processing of complex glycans were increased. Microbial cross-feeding with sialic acid, fucose, and rhamnose was enhanced, whereas hydrogen sulfide production was reduced. Finally, microbial proteins involved in antibiotic resistance and inflammation were more abundant after therapy. Moreover, a reduction in host proteins with known roles in inflammation and H. pylori-mediated carcinogenesis was observed. In conclusion, our results support the use of metaproteomics to monitor drug-induced remodeling of GM and host functions, opening the way for investigating new antimicrobial therapies aimed at preserving gut environmental homeostasis
Metagenomic Changes of Gut Microbiota following Treatment of Helicobacter pylori Infection with a Simplified Low-Dose Quadruple Therapy with Bismuth or Lactobacillus reuteri
Background: Probiotic supplementation to antibiotic regimens against Helicobacter pylori infection has been proposed to improve eradication rate and to decrease detrimental effects on gut microbiota. Aims: To evaluate microbiota modifications due to a low-dose quadruple therapy with bismuth or Lactobacillus reuteri. Methods: Forty-six patients infected with H. pylori were prospectively enrolled in a single-centre, randomized controlled trial to receive b.i.d. with meals for 10 days low-dose quadruple therapy consisting of rabeprazole 20 mg and bismuth (two capsules of Pylera® plus 250 mg each of tetracycline and metronidazole), or the same dose of rabeprazole and antibiotics plus Gastrus® (L. reuteri), one tablet twice-a-day for 27 days. Stool samples were collected at the enrolment, at the end and 30–40 days after the treatment. Gut microbiota composition was investigated with 16S rRNA gene sequencing. Results: Eradication rate was by ITT 78% in both groups, and by PP analysis 85.7% and 95.5% for Gastrus® and bismuth group, respectively. Alpha and beta diversity decreased at the end of treatment and was associated with a reduction of bacterial genera beneficial for gut homeostasis, which was rescued 30–40 days later in both groups, suggesting a similar impact of the two regimens in challenging bacterial community complexity. Conclusions: Low-dose bismuth quadruple therapy proved to be effective with lower costs and amount of antibiotics and bismuth. Gastrus® might be an option for patients with contraindications to bismuth. L. reuteri was unable to significantly counteract dysbiosis induced by antibiotics. How to administer probiotics to prevent gut microbiota alterations remains an open question
The Sardinian Germplasm Bank (BG-SAR): an important tool for the preservation of Mediterranean plant diversity. Conservation studies on Mediterranean threatened flora and vegetation
The Sardinian Germplasm Bank (BG-SAR) is part of the Hortus Botanicus Karalitanus (HBK), which belongs to the University of Cagliari (Italy). The main objective of BG-SAR is the conservation, study and management of germplasm of Sardinian endemic, threatened and policy species (taxa inserted in the Habitat Directive 92/43/EEC, CITES and Bern Convention; Fenu et al., 2015), as well as Crop Wild Relatives (CWR), landraces and
useful plants. Before of long-term conservation at -25°C, the image digitalization of each seed lot is acquired, in order to allow subsequent studies through the innovative morphocolorimetric techniques. Studies on the germination ecophysiology are carried out to increase the ecological knowledge and define the optimum germination protocol for all the preserved taxa. In the last years, particular attention was given to studies on thermal time, niche modeling and the effect of global warming on the seed germination of mountain Mediterranean species (e.g. Porceddu et al., 2013), and to understand how the thermal thresholds for dormancy loss and germination may vary along an altitudinal gradient.
Moreover, comparative studies on the effects of abiotic stresses, such as salinity (e.g. NaCl), or the nutrient availability (e.g. KNO3) were carried out among several Mediterranean species, especially for endangered coastal taxa (e.g. Santo et al., 2014). In the case of invasive alien species (IAS), the identification of their tolerance to salt, has helped us to predict their potential invasive power also in salt habitats.
In addition, archaeological materials such as seeds and fruits were studied and stored at BG-SAR, with the aim of investigating the evolution of crops and wild plants. All these approaches allow to BG-SAR, not only to attain an effective ex-situ conservation, but also to face actual and important problems, such as global warming and invasiveness of alien species and, deepen the knowledge of the endangered Mediterranean species