Immunological and histological changes of gilthead sea bream (Sparus Aurata) to Alum, when used as an adjuvnat in Photobacterium damselae ssp piscicida vaccine

Dissertação mest., Aquacultura e Pescas, Universidade do Algarve, 2006Pseudotuberculosis or pasteurellosis is caused by the microorganism Photobacterium damselae ssp piscicida (formely Pasteurella piscicida). Vaccines are one of the most efficient methods for this control. Together with this, adjuvants are enhancers of fish immune response. The aim of this research is to understand the effects of the Aluminium Potassium Sulfate (Alum) when used as an adjuvant of fish vaccines by immersion, namely in the sea bream (Sparus aurata) histological and specific immunological response

Finnish Campylobacter jejuni Strains of Multilocus Sequence Type ST-22 Complex Have Two Lineages with Different Characteristics

Peer reviewe

Sialylation of Helicobacter bizzozeronii lipopolysaccharides modulates Toll-like receptor (TLR) 2 mediated response

Abstract Sialic acid in lipopolysaccharides (LPS) of mucosal pathogens is known to be an important virulence factor. Few strains of Helicobacter pylori express sialyl-Lewis-X and we have reported that human and canine Helicobacter bizzozeronii strains express sialyl-lactoseamine in their LPS. However, the role of sialyation of Helicobacter LPS in the interaction with the host cells is still unknown. In this study H. bizzozeronii LPS is shown to activate the TLR2 in a dose and strain dependent manner in the in vitro HEK-293 cells model expressing TLR2, but not the cells expressing TLR4. These results indicate that TLR2 is the specific receptor for H. bizzozzeronii LPS, as previously described for H. pylori. To further explore the role of sialylation of H. bizzozeronii LPS on TLR2 response, H. bizzozeronii Δhbs2 mutant strains deficient in sialyltransferase activity were constructed by homologous recombination. LPS from H. bizzozeronii Δhbs2 strains enhanced the NF-ĸB induction via TLR2 compared to the respective wild types, leading to the conclusion that the sialylation of H. bizzozeronii LPS in wild-type strains may modulate host immune response

Estimation and implications of the genetic architecture of fasting and non-fasting blood glucose

This upload includes the sample code that was used in the paper "Estimation and implications of the genetic architecture of fasting and non-fasting blood glucose", which has been accepted for publication in Nature Communications. Abstract The genetic regulation of post-prandial glucose levels is poorly understood. Here, we characterise the genetic architecture of blood glucose variably measured within 0 and 24 hours of fasting in 368,000 European ancestry participants of the UK Biobank. We found a near-linear increase in the heritability of non-fasting glucose levels over time, which plateaus to its fasting state value after 5 hours post meal (h2=11%; standard error: 1%). The genetic correlation between different fasting times is > 0.77, suggesting that the genetic control of glucose is largely constant across fasting durations. Accounting for heritability differences between fasting times leads to a ~16% improvement in the discovery of genetic variants associated with glucose. Newly detected variants improve the prediction of fasting glucose and type 2 diabetes in independent samples. Finally, we meta-analysed summary statistics from genome-wide association studies of random and fasting glucose (N=518,615) and identified 156 independent SNPs explaining 3% of fasting glucose variance. Altogether, our study demonstrates the utility of random glucose measures to improve discovery of genetic variants associated with glucose homeostasis, even in fasting conditions

Genome analysis of Campylobacter jejuni strains isolated from a waterborne outbreak

Peer reviewe

Comparative genomics of unintrogressed Campylobacter coli clades 2 and 3

Peer reviewe

Evidence for conserved function of γ–glutamyltranspeptidase in Helicobacter genus

The confounding consequences of Helicobacter bilis infection in experimental mice populations are well recognized, but the role of this bacterium in human diseases is less known. Limited data are available on virulence determinants of this species. In Helicobacter pylori, γ-glutamyltranspeptidase (γGT) contributes to the colonization of the gastric mucosa and to the pathogenesis of peptic ulcer. The role of γGT in H. bilis infections remains unknown. The annotated genome sequence of H. bilis revealed two putative ggt genes and our aim was to characterize these H. bilis γGT paralogues. We performed a phylogenetic analysis to understand the evolution of Helicobacter γGTs and to predict functional activities of these two genes. In addition, both copies of H. bilis γGTs were expressed as recombinant proteins and their biochemical characteristics were analysed. Functional complementation of Escherichia coli deficient in γGT activity and deletion of γGT in H. bilis were performed. Finally, the inhibitory effect of T-cell and gastric cell proliferation by H. bilis γGT was assessed. Our results indicated that one gene is responsible for γGT activity, while the other showed no γGT activity due to lack of autoprocessing. Although both H. bilis and H. pylori γGTs exhibited a similar affinity to L-Glutamine and γ-Glutamyl-p-nitroanilide, the H. bilis γGT was significantly less active. Nevertheless, H. bilis γGT inhibited T-cell proliferation at a similar level to that observed for H. pylori. Finally, we showed a similar suppressive influence of both H. bilis and H. pylori γGTs on AGS cell proliferation mediated by an apoptosis-independent mechanism. Our data suggest a conserved function of γGT in the Helicobacter genus. Since γGT is present only in a few enterohepatic Helicobacter species, its expression appears not to be essential for colonization of the lower gastrointestinal tract, but it could provide metabolic advantages in colonization capability of different niches.Peer reviewe

Assessment of the efficacy of a feed additive consisting of Limosilactobacillus reuteri (formerly Lactobacillus reuteri) DSM 32203 for dogs (NBF LANES)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the efficacy of Limosilactobacillus reuteri (formerly Lactobacillus reuteri) DSM 32203 as a zootechnical additive for dogs. The additive is a preparation of viable cells of L. reuteri DSM 32203 and it has not been previously authorised as a feed additive in the European Union. The additive is intended for use in complete feed for dogs at a minimum use level of 6 x 10(9) colony forming units (CFU) per animal and day. In a previous opinion, the FEEDAP Panel could not conclude on the efficacy of L. reuteri DSM 32203 for dogs. The applicant has provided supplementary information to support the efficacy of the additive to dogs. Based on the data provided, the FEEDAP Panel concludes that L. reuteri DSM 32203 has the potential to improve faecal consistency by reducing the moisture content of stools from dogs receiving the additive at 1 x 10(10) CFU/kg feed. However, the Panel has some reservations on the effects in the moisture content of stools, which if maintained over time might cast doubts on the benefits on the long-term use of the additive since it could lead to constipation

Safety and efficacy of a feed additive consisting of Limosilactobacillus reuteri (formerly Lactobacillus reuteri) DSM 32264 as a feed additive for cats (NBF Lanes s.r.l.)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the efficacy of a product consisting of Limosilactobacillus reuteri (formerly Lactobacillus reuteri) DSM 32264 as a zootechnical additive for cats. The additive is a preparation of viable cells of L. reuteri DSM 32264 and it has not been previously authorised as a feed additive in the European Union. The additive is intended for use in complete feed for cats at a minimum inclusion level of 6 9 109 colony forming units (CFU) per animal and day. In a previous opinion, the FEEDAP Panel could not conclude on the efficacy of L. reuteri DSM 32264 for cats. The applicant has provided supplementary information to support the efficacy of the additive for cats. Based on the data provided, the FEEDAP Panel concluded that L. reuteri DSM 32264 has the potential to improve faecal consistency by reducing the moisture content of stools from cats receiving the additive at 1 9 1010 CFU/kg feed. However, the Panel had some reservations on the effects in the moisture content, which if maintained overtime, might cast doubts on the benefits on the long-term use of the additive since it could lead to constipation