Identification and characterization of the Atlantic salmon peptide transporter 1a

Peptide transporter 1 (PepT1) mediates the uptake of dietary di-/tripeptides in vertebrates. However, in teleost fish gut, more than one PepT1-type transporter might operate, because of teleost-specific whole gen(om)e duplication event(s) that occurred during evolution. Here, we describe a novel teleost di-/tripeptide transporter, i.e., the Atlantic salmon (Salmo salar) peptide transporter 1a [PepT1a; or solute carrier family 15 member 1a (Slc15a1a)], which is a paralog (77% similarity and 64% identity at the amino acid level) of the well-described Atlantic salmon peptide transporter 1b [PepT1b, alias PepT1; or solute carrier family 15 member 1b (Slc15a1b)]. Comparative analysis and evolutionary relationships of gene/protein sequences were conducted after ad hoc database mining. Tissue mRNA expression analysis was performed by quantitative real-time PCR, whereas transport function analysis was accomplished by heterologous expression in Xenopus laevis oocytes and two-electrode voltage-clamp measurements. Atlantic salmon pept1a is highly expressed in the proximal intestine (pyloric ceca ≈ anterior midgut > midgut >> posterior midgut), in the same gut regions as pept1b but notably ~5-fold less abundant. Like PepT1b, Atlantic salmon PepT1a is a low‐affinity/high‐capacity system. Functional analysis showed electrogenic, Na+-independent/pH-dependent transport and apparent substrate affinity (K0.5) values for Gly-Gln of 1.593 mmol/L at pH 7.6 and 0.076 mmol/L at pH 6.5. In summary, we show that a piscine PepT1a-type transporter is functional. Defining the role of Atlantic salmon PepT1a in the gut will help to understand the evolutionary and functional relationships among peptide transporters. Its functional characterization will contribute to elucidate the relevance of peptide transporters in Atlantic salmon nutritional physiology.acceptedVersio

Functional characterization of iron transporter from Dictyostelium discoideum as a model of cellular iron homeostasis

Iron plays a central role in a large number of essential cellular functions but it is also potentially toxic being able to generate reactive oxygen species. The social amoeba Dictyostelium discoideum possesses several iron genes with the exception of transferrin, ferritin and TFR (Bozzaro et al., 2013; Peracino et al., 2013) and represents a model for the study of cellular iron homeostasis showing subcellular localization of iron transporters resembling that of macrophages. In particular, D. discoideum expresses the ortholog of Nramp1 transporter in phago-lysosomes and that of Nramp2 in the contractile vacuole. To better understand the function of dd Nramp1, the protein was expressed in Xenopus laevis oocytes by cRNA injection and functionally tested by radiochemical and electrophysiological techniques. To increase the surface localization of dd Nramp1, its N and C termini were replaced with the corresponding regions of the murine DMT1, which shows a high level of expression in the membrane of X. laevis oocytes (Gunshin et al., 1997). Dd Nramp1 is an electrogenic proton-dependent divalent metal ion transporter with a cation selectivity comparable to that of the murine DMT1 (Illing et al., 2012). It transports ferrous but not ferric iron and it is partially inhibited by Na+

The peptide transporter 1a of the zebrafish Danio rerio, an emerging model in nutrigenomics and nutrition research: Molecular characterization, functional properties, and expression analysis

Background: Peptide transporter 1 (PepT1, alias Slc15a1) mediates the uptake of dietary di/tripeptides in all vertebrates. However, in teleost fish, more than one PepT1-type transporter might function, due to specific whole genome duplication event(s) that occurred during their evolution leading to a more complex paralogue gene repertoire than in higher vertebrates (tetrapods). Results: Here, we describe a novel di/tripeptide transporter in the zebrafish (Danio rerio), i.e., the zebrafish peptide transporter 1a (PepT1a; also known as Solute carrier family 15 member a1, Slc15a1a), which is a paralogue (78% similarity, 62% identity at the amino acid level) of the previously described zebrafish peptide transporter 1b (PepT1b, alias PepT1; also known as Solute carrier family 15 member 1b, Slc15a1b). Also, we report a basic analysis of the pept1a (slc15a1a) mRNA expression levels in zebrafish adult tissues/organs and embryonic/early larval developmental stages. As assessed by expression in Xenopus laevis oocytes and two-electrode voltage clamp measurements, zebrafish PepT1a, as PepT1b, is electrogenic, Na+-independent, and pH-dependent and functions as a low-affinity system, with K0.5 values for Gly-Gln at − 60 mV of 6.92 mmol/L at pH 7.6 and 0.24 mmol/L at pH 6.5 and at − 120 mV of 3.61 mmol/L at pH 7.6 and 0.45 mmol/L at pH 6.5. Zebrafish pept1a mRNA is highly expressed in the intestine and ovary of the adult fish, while its expression in early development undergoes a complex trend over time, with pept1a mRNA being detected 1 and 2 days post-fertilization (dpf), possibly due to its occurrence in the RNA maternal pool, decreasing at 3 dpf (~ 0.5-fold) and increasing above the 1–2 dpf levels at 4 to 7 dpf, with a peak (~ 7-fold) at 6 dpf. Conclusions: We show that the zebrafish PepT1a-type transporter is functional and co-expressed with pept1b (slc15a1b) in the adult fish intestine. Its expression is also confirmed during the early phases of development when the yolk syncytial layer is present and yolk protein resorption processes are active. While completing the missing information on PepT1-type transporters function in the zebrafish, these results open to future investigations on the similar/differential role(s) of PepT1a/PepT1b in zebrafish and teleost fish physiology.publishedVersio

Safety in wine production. A pilot study on the quality evaluation of prosecco wine in the framework of ue regulation

In Italy, wine production is considered a sector of excellence, where the wines’ appreciable sensory features are favored by environmental factors, including weather and climate conditions, which benefit territories with a specific vocation. The whole chain involves many economic and agri-food sector operators, and requires an in-depth assessment of specific risks for identifying critical points, keeping the entire production process under control, and ensuring product traceability. This article describes the results of a pilot study conducted in the Prosecco DOCG (Designations of Controlled and Guaranteed Origin) area, concerning the detection of residues of plant protection products in fifty wine bottles. Although considerably below the maximum residue levels, all the samples tested were positive, ranging from two to five active substances detected in each sample. In addition to the provisions of the European Community legislation, this paper critically evaluates some best practices models that are already used by the Wine Federations of Italy, with the aim of identifying advantages of and areas for improvement in production methods, applicable to raw materials reception, rasping, storage, and bottling phases, in order to guarantee product safety and quality

Age-Related Patterns in Clinical Presentations and Gluten-Related Issues Among Children and Adolescents With Celiac Disease

OBJECTIVES: Celiac disease (CD) is common and often cited as an “iceberg” phenomenon (i.e., an assumed large number of undiagnosed cases). Recently, atypical or asymptomatic manifestations are becoming more commonly described in older children and adolescents. Moreover, CD diagnosis in children can be complicated by several factors, including its diverse clinical presentations, delay in recognizing CD signs and symptoms, and premature dietary gluten avoidance before the formal diagnosis of CD. To date, few studies have directly examined age-related differences in clinical characteristics and gluten-related issues among children with CD. The aim of this study was to determine age-related patterns in clinical characteristics and gluten-related issues among children with confirmed CD. METHODS: We performed a structured medical record review of biopsy-proven CD patients, aged 0–19 years, between 2000 and 2010 at a large Boston teaching hospital. Data collection included demographics, medical history, gluten-related issues, and diagnostic investigations (CD-specific serology, upper gastrointestinal endoscopy, and small intestinal biopsy). The first positive duodenal biopsy with Marsh III classification defined age of diagnosis. Patients were divided into three age groups for comparisons of the aforementioned characteristics: infant-preschool group (0–5 years), school-aged group (6–11 years), and adolescence group (12–19 years). RESULTS: Among 411 children with biopsy-proven CD, the mean age was 9.5 (s.d. 5.1) years. Most were female (63%) and white (96%). All children had positive CD-specific serology. Most children presented with either abdominal complaints or bowel movement changes. Overall, boys were more common among infant-preschool group compared with the other age groups. More distinct clinical manifestations (vomiting, bowel movement changes, and weight issues) were apparent in the youngest group, whereas school-aged children had more subjective abdominal complaints at the initial presentation. Conversely, the adolescents were most likely to present without any gastrointestinal (GI) symptoms, but not when this was combined with absence of weight issues. Age of diagnosis was not associated with atypical extraintestinal CD presentations. Regarding the gluten-related issues, 10% of school-aged children avoided dietary gluten before the formal CD diagnosis, and 27% of the adolescents reported dietary gluten transgression within the first 12 months of diagnosis, significantly higher than the other age groups. Age differences in histopathology were also found. Whereas the infant-preschool group had a higher proportion of total villous atrophy, the older children were more likely to have gross duodenal abnormalities and chronic duodenitis suggestive of CD at the time of diagnosis. CONCLUSIONS: Children and adolescents with CD have age-related patterns in both the clinical presentations and gluten-related issues. More pronounced clinical and histological features were determined in younger children, whereas older children more commonly presented with solely subjective abdominal complaints or even without any GI symptoms. However, silent and atypical extraintestinal CD presentations were comparable between age groups. In addition to the aforementioned presentations, the higher rates of dietary gluten avoidance and transgression in older children make CD diagnosis and management particularly challenging. These age-related patterns may further increase awareness, facilitate early diagnosis, and improve patient care of pediatric CD

Health communication in covid-19 era: Experiences from the italian vaccinarsì network websites

In 2013, in a bid to combat Vaccine Hesitancy (VH) and provide information on vaccines by communicating with the general public and the health community (e.g., healthcare workers and public health operators), the Italian Society of Hygiene and Preventive Medicine (S.It.I.) published the national website “VaccinarSì”. The project was subsequently extended to ten Italian Regions. This led to the creation of the VaccinarSì Network, whose websites are publicly owned. The aim of this work was to present the framework of the websites of the VaccinarSì Network and to analyse user behaviour in the pre-COVID-19-era (dating from each website’s publication until 31 January 2020) and in the COVID-19-era (from 1 February 2020 to 31 January 2021). Some metrics such as the number of visits to the site (sessions, number of users and average session duration), user behaviour (pages viewed, bounce rate and organic search) and the session acquisition path (direct traffic, referrals and social traffic) were searched, extrapolated and processed with Google Analytics. Qualitative and normally distributed quantitative variables were summarised with their absolute (relative) frequencies and means. Statistical differences between the means of the two periods were evaluated through paired t-test. A two-tailed p-value less than 0.05 was considered to be statistically significant. When the total values recorded over the period were compared, an overall increase in metrics was observed—the number of individual users, visits and individual pageviews rose in a statistically significant way. Our study aimed to highlight how combining disciplines such as health education and digital communication via Information and Communication Technologies (ICT) represents the best strategy to support citizens. This approach gives them the tools to become independent and responsible players that are capable of voluntarily and consciously choosing to adhere to vaccination programs. The VaccinarSì Network’s goal for the future is to reach an even wider audience. By building each user’s critical knowledge, this network enables users to be active components of a wider, more empowered community

A formula containing galacto- and fructo-oligosaccharides prevents intestinal and extra-intestinal infections : an observational study

BACKGROUND & AIM: The addition of prebiotics to infant formula modifies the composition of intestinal microflora. Aim of the study was to test the hypothesis that prebiotics reduce the incidence of intestinal and respiratory infections in healthy infants. METHODS: A prospective, randomized, placebo-controlled, open trial was performed. Healthy infants were enrolled and randomized to a formula additioned with a mixture of galacto- and fructo-oligosaccharides or to a control formula. The incidence of intestinal and respiratory tract infections and the anthropometric measures were monitored for 12 months. RESULTS: Three hundred and forty two infants (mean age 53.7+/-32.1 days) were enrolled. The incidence of gastroenteritis was lower in the supplemented group than in the controls (0.12+/-0.04 vs. 0.29+/-0.05 episodes/child/12 months; p=0.015). The number of children with more than 3 episodes tended to be lower in prebiotic group (17/60 vs. 29/65; p=0.06). The number of children with multiple antibiotic courses/year was lower in children receiving prebiotics (24/60 vs. 43/65; p=0.004). A transient increase in body weight was observed in children on prebiotics compared to controls during the first 6 months of follow-up. CONCLUSIONS: Prebiotic administration reduce intestinal and, possibly, respiratory infections in healthy infants during the first year of age