The gender gap in names of prokaryotes honouring persons.

The aim of this study is to analyse prokaryotic names which honour persons, eponyms, from a gender perspective. Data were retrieved from the List of Prokaryotic names with Standing in Nomenclature. Excluding new combinations, the etymologies of 23 315 unique names at the rank of genus, species and subspecies were analysed. A total of 2018 (8.7 %) names honour persons (eponyms), for which the development of the female share over time was further investigated. Women started to be honoured very recently (1947) compared to men (1823). Moreover, only 14.8 % of all prokaryotic eponyms refer to females. This ratio has hardly improved since 1947, although the number of women whose contributions to microbiology could have been recognized has increased over time. In contrast, about 50 % of prokaryotic names derived from mythological characters refer to females. To reduce this gender gap, we encourage authors proposing new taxon names to honour female scientists who can serve as role models for new generations.

Bacterial extracellular vesicles and associated functional proteins in fermented dairy products with Lacticaseibacillus paracasei.

Cells of all kingdoms produce extracellular vesicles (EVs); hence, they are present in most environments and body fluids. Lacticaseibacillus paracasei produces EVs that have attached biologically active proteins (P40 and P75). In this study, EV and functional proteins were found in five different commercial dairy-fermented products carrying L. paracasei. Strains present in those products were isolated, and with one exception, all produced small EVs (24-47 d.nm) carrying P40 and P75. In order to winnow bacterial EV from milk EV, products were subjected to centrifugal fractionation at 15,000 × g (15 K), 33,000 × g (33 K), and 100,000 × g (100 K). P75 was present in all supernatants and pellets, but P40 was only found in two products bound to the 15 and 33 K pellets, and 16S rDNA of L. paracasei could be amplified from all 100 K EVs, indicating the presence of L. paracasei EV. To investigate the interactions of bacterial EV and proteins with milk EV, L. paracasei BL23 EV was added to three commercial UHT milk products. Small-size vesicles (50-60 d.nm) similar to L. paracasei BL23 EV were found in samples from 100 K centrifugations, but intriguingly, P40 and P75 were bound to EV in 15 and 33 K pellets, containing bovine milk EV of larger size (200-300 d.nm). Sequencing 16S rDNA bands amplified from EV evidenced the presence of bacterial EVs of diverse origins in milk and fermented products. Furthermore, L. paracasei 16S rDNA could be amplified with species-specific primers from all samples, showing the presence of L. paracasei EV in all EV fractions (15, 33, and 100 K), suggesting that these bacterial EVs possibly aggregate and are co-isolated with EV from milk. P40 and P75 proteins would be interacting with specific populations of milk EV (15 and 33 K) because they were detected bound to them in fermented products and milk, and this possibly forced the sedimentation of part of L. paracasei EV at lower centrifugal forces. This study has solved technically complex problems and essential questions which will facilitate new research focusing on the molecular behavior of probiotics during fermentation and the mechanisms of action mediating the health benefits of fermented products.

Study of the immune response in celiac patients with selective IgA deficiency who start a gluten-free diet.

Studies are scarce regarding IgG anti-tissue transglutaminase 2 (tTG) normalization in selective IgA deficient (SIgAD) celiac disease (CD) patients after beginning a gluten free diet (GFD). The aim of this study is to analyse the decreasing dynamics of IgG anti-tTG in patients diagnosed with CD who start a GFD. To achieve this objective, IgG and IgA anti-tTG levels at diagnosis and during follow-up in 11 SIgAD CD patients and in 20 IgA competent CD patients were retrospectively evaluated. At diagnosis, statistical differences were not found when comparing IgA anti-tTG levels of IgA competent subjects with IgG anti-tTG levels of SIgAD subjects. Regarding the decreasing dynamics, even though no statistical differences were found (p = 0.06), normalization rates were slower for SIgAD CD patients. After 1 and 2 years on GFD, respectively, only 18.2% and 36.3% of the SIgAD CD patients normalized IgG anti-tTG levels; otherwise, IgA anti-tTG reached values under the reference values in 30% and 80% of the IgA competent patients in the same time-points. Although IgG anti-tTG has demonstrated a high diagnostic efficiency in SIgAD CD pediatric patients, this test does not appear to be as precise for long-term GFD response monitoring as IgA anti-tTG levels in IgA sufficient patients.

Intestinal anti-tissue transglutaminase IgA deposits as a complementary method for the diagnostic evaluation of celiac disease in patients with low-grade histological lesions.

Evaluating the usefulness of intestinal anti-transglutaminase IgA (anti-TG2 IgA) deposits detection as a complementary or decision-supporting tool in the diagnosis of celiac disease (CD) in patients with low degree of enteropathy. Small intestinal biopsies (SIB) were performed from 2008 to 2017 in patients on suspicion of CD (positive CD serology and/or symptoms) referred to our Pediatric Gastroenterology Unit. We determined anti-TG2 IgA deposits by using double immunofluorescence in all the patients in whom Marsh 0 or Marsh 1 was detected in the conventional histological study and in a random selection of patients with clearly positive serology and histological Marsh 2-3 lesion. Seventy-five pediatric patients were split into three groups according to the final diagnosis: (i) 13 children with a Marsh 0 or 1, negative CD serology and final non-CD diagnosis; none presented intestinal anti-TG2 IgA deposits; (ii) 15 potential CD cases (Marsh 0 or 1 and CD-associated antibodies), detecting anti-TG2 IgA deposits in 12; on follow-up, another biopsy performed in 11/15 showed villi atrophy in seven and a Marsh 2 lesion in two of them, patients being finally diagnosed as CD cases; and (iii) 47 children with Marsh 2-3 histological lesion and final CD diagnosis; all of them had intestinal anti-TG2 IgA deposits. Anti-TG2 deposits are a useful complementary tool for CD diagnosis in pediatric population with digestive pathologies suggestive of CD. It is especially helpful in those with low-grade lesion, in which anti-TG2 deposits are predictive of the development of more severe lesions on follow-up.