Month: January 2020

sEng levels also increased with gestational age in normotensive pregnancy, indicating that the gestational age was associated with a greater anti-angiogenic profile. This finding is according to previous studies that found higher sEng and lower PlGF levels, and higher/PlGF ratio in older gestational age. Previous studies have demonstrated that sEng is elevated in PE and before the onset of the disease. In contrast to normotensive pregnant women, there is a negative association between sEng levels and gestational age in PE. Accordingly, we found higher sEng levels in PE comparing to normotensive pregnant women that correlated negatively with gestational age. In addition, sEng levels were independently associated with the development of PE, reinforcing the role of sEng in disease pathogenesis. Our data demonstrated that primiparity was also independently associated with pregnancy outcome. In agreement with other studies, we found a tendency of increased sEng levels in early-onset comparing to late-onset PE. Consistent with previous reports, we also found a significant increase of sEng levels in severe PE compared with mild PE. In addition, sEng levels were independently associated with the disease severity. It is well known that blood pressure and protein excretion are increased in preeclamptic women with the severe form of the disease. A recent study has indicated an association between sEng and high blood pressure in pregnancy. In one animal model of PE, the administration of adenovirus encoding sEng produced hypertension, proteinuria and endothelial dysfunction, further amplified by the coadministration of sEng and sFlt1, leading to a severe PE-like disease including HELLP syndrome and fetal growth restriction. In line with these experimental data, we found that systolic blood pressure was positively associated with sEng levels in PE. In accordance to Zhang et al., we showed that sEng and creatinine levels were positively associated in PE. Angiogenesis play a critical role in renal homeostasis, since glomeruli form the functional barrier between the blood and urinary compartment. Genetic studies in mice have revealed an important role of the proangiogenic factors VEGF and PlGF in renal development and vascular health. On the other hand, the anti-angiogenic factors sFlt-1 and sEng have been associated with glomerular damage and proteinuria. Venkatesha et al. showed that proteinuria was modest in sEng-treated rats and severe in sFlt-1treated group, while a nephrotic-range proteinuria was found using both sFlt-1 and sEng. Masuyama et al. demonstrated a tendency of increased proteinuria levels in high sEng group compared to low sEng group. Hepatic function may be significantly altered in PE women, especially in those with the severe form of the disease and this alteration is even more pronounced in HELLP syndrome.

We propose that this property gives UCC2003 a competitive advantage in iron-limited environments such as the gastrointestinal tract. The importance of iron acquisition mediated nutritional immunity in gut pathogen protection was further demonstrated by the fact that two additionally constructed mutants harboring insertions in either of two presumed ironuptake genes proved to have a decreased ability to confer protection against Salmonella infection in the C. elegans model. In addition and as expected, these mutants were more susceptible to the iron chelators as compared to the parent strain B. breve UCC2003. It has previously been shown that LuxS affects genes involved in iron metabolism in Porphyromonas gingivalis, Vibrio vulnificus, Mannheimia haemolytica and Actinobacillus pleuropneumoniae, while it was also demonstrated that iron availability increases the pathogenic potential of several gastrointestinal pathogens including S. Typhimurium, Citrobacter freundii, E. coli and Listeria monocytogenes. Our results are consistent with the notion that bifidobacteria confer gut pathogen protection by nutritional immunity. This in turn suggests that LuxS/AI-2 can be versatile in various bacterial species and conditions. Since the colonization capacity of a probiotic bacterium is considered to be a prerequisite to exert its beneficial effects, the observation that AI-2-expressing B. breve UCC2003 outcompetes an isogenic derivative lacking this capacity contributes to the elucidation of molecular players and mechanisms of colonization requirements and probiotic effects. Indeed, one application where administration of bifidobacterial strains may positively influence health is in the prevention of necrotizing enterocolitis in premature infants. The precise causative agent of NEC is unknown; however, the preterm infant microbiota has been found to be dominated by pathogenic genera with Proteobacteria and Enterobacteriaceae dominating rather than characteristic species belonging to Bacteroidetes, Clostridium and Bifidobacterium. The dominance of potentially pathogenic bacteria may increase the risk of infection in this vulnerable group. Neonatal nurseries in Finland, Italy and Japan have been routinely and successfully using probiotics as prophylaxis against NEC for over a decade, without ever reporting any adverse effects. Despite the safe use of practice and numerous randomized clinical trials that indicate that probiotics can reduce the incidence of NEC by at least 30%, clinical guidelines by the American Society for Parenteral and Enteral Nutrition express the view that there is currently insufficient data to recommend the use of probiotics in infants at risk of NEC. Integral to the resistance to adopt probiotics as a prophylaxis against NEC in premature infants is the lack of knowledge on the mechanism of action.

Critical to understanding these peptides and utilising their properties therapeutically is the need to clarify their modes of action in vivo in infectious contexts. In this study, an acute murine pulmonary infection model with P. aeruginosa was utilised in order to evaluate the capacity of cathelicidins to enhance host defence against infection with a microbe which is largely resistant to these peptides under physiological conditions in vitro. Under favourable in vitro conditions in which microbicidal properties are evident for LL-37, this peptide has been shown to permeabilise bacterial membranes within minutes. However, we found no evidence for direct microbicidal activity against P. aeruginosa after coincubation with LL-37 in vivo, yet exogenously delivered LL-37 was found to significantly enhance pathogen clearance over 24 hours. Although we cannot exclude some alternative form of late direct microbicidal activity of LL-37, even by 6 hours after infection no significant impact on bacterial load of the whole lung could be demonstrated in response to LL-37 treatment, although interestingly a therapeutic bolus of peptide was found to diminish the number of live bacteria accessible to bronchoalveolar lavage at this time point. The reason for this is unclear, but may relate to early removal of the most accessible bacteria by the enhanced neutrophil influx observed. A previous study using adenoviral vectors carrying the cDNA for hCAP18/LL-37, to overexpress the human cathelicidin in the murine lung over the 5 days prior to infection, resulted in the promotion of a small, but significant enhancement of P. aeruginosa clearance from the murine lung over a 24 hour period. This was observed to be accompanied by decreased pulmonary TNF levels, but the mechanism underpinning this therapeutic effect was not evaluated and was assumed to be microbicidal. In contrast, we found no evidence to support a microbicidal effect, but demonstrate a peptide-mediated enhanced early neutrophil influx in vivo. Prior research has demonstrated the capacity for cathelicidins to have direct chemotactic activity for human neutrophils and monocytes and murine leukocytes in vitro and for murine leukocytes in an experimentally-formed murine air pouch model. In that in vivo model, injection of 2 mM LL-37 or mCRAMP into the air pouch significantly enhanced the influx of neutrophils and monocytes within a 4 hour period. This is in contrast to the complete absence of neutrophils observed in our studies in the murine lung 6 hours after instillation of LL-37 alone. In addition, LL-37 was not found to mediate any significant effects on the number of monocytes in the BALF, in contrast to the previously published findings in other systems. A small, but significant neutrophil response was observed in the lungs of LL-37treated uninfected mice at 24 hours after instillation, demonstrating some LL-37-mediated neutrophil influx.

IVS7-ISS motif revealed overall similar binding of hnRNP A1 to the motif, compared to the human wild type IVS7-ISS, despite a putative increase in the strength of the distal hnRNP A1 core motif. The loss of this site is likely enough to effectively disrupt the function of the entire ISS in the context of pig Smn1 exon 7. This is in line with previous evidence that suggests a more central role of the proximal site compared to the distal site. In the context of human SMN2 exon 7, abrogation of this site improves the inclusion of exon 7, indicating that this site is a major contributor to the inefficient splicing of human SMN2 exon 7. Additionally, the IVS7-ISS has proved a valuable therapeutic target and has resulted in on-going clinical trials with an ASO specifically blocking this ISS motif. Together, these findings indicate that in pigs, the IVS7-ISS is inactive due to a mutation in the proximal hnRNP A1 site and this inactivation has relaxed the requirements for a strong ESE at the 39ss of exon 7. This indicates that insertion of an SMN2-like mutation in the endogenous porcine Smn1 gene would be insufficient to recapitulate the splicing of SMN2 exon 7 and that insertion of a larger fragment of the human SMN2 gene would be required. In the mouse, the SRSF1 ESE is identical to the human ESE but like the pig, the mouse IVS7-ISS is abrogated in the proximal site. Furthermore, the distal site does not appear to be strengthened indicating that the ISS is likely to be functionally weakened also in the mouse. These observations indicate that the human ISS would have to be inserted into the murine Smn1 gene if Smn1 exon 7 skipping was to be induced by an +6C.T mutation, but a mouse model containing a murine Smn1 to Smn2-like conversion has been published without insertion of the human ISS. This model exhibited a milder SMA phenotype similar to human SMA type III, indicating that even though the Smn2-like exon 7 was skipped, the level of inclusion was still higher than human SMN2 exon 7, resulting in a mild phenotype. One possible explanation for this, is that the murine ISS contains a 3 bp deletion which moves the distal site in closer proximity to the 59ss, although not as close as the proximal site of the human ISS. This indicates that the inhibitory function of this hnRNP A1 core motif may be highly dependent on its proximity to the 59ss and that it may function by directly blocking access of U1 snRNP to the 59ss, and not by inducing a polymerization of hnRNP A1 proteins along exon 7, or by looping out the exon through interaction with other ISS/ESS elements, such as the hnRNP A1 binding motif spanning the 39ss of exon 7 or the hnRNP A1 motif generated across the previous SRSF1 binding ESE in SMN2. In conclusion, we established the presence of a functional and likely SRSF1 binding ESE in porcine Smn1, that this ESE may be disrupted by a mutation similar.

Populations and implementation of more genetic markers, one can expect differences to diminish between mixture model estimates and estimates that condition on preliminary IA. Even so, mixture modeling will continue to enjoy the strongest theoretical foundation and some degree of superior statistical performance as long as uncertainty exists in IA. In this study, we seek the same statistical robustness for ecological and phenotypic trait inference that has been demonstrated for mixture modeling as compared to IA. We extend the Bayesian genetic mixture model to incorporate parameters associated with phenotypic traits. The conditional maximum likelihood model of Bromaghin et al. is incorporated into a Bayesian framework. Again, the conceptual advantage of this approach is the utilization of all available information in a mixture sample, along with its uncertainty, and minimizing potential biases stemming from conditioning on prior estimates of population membership. The performance of the Bayesian mixture model is assessed through comparison with that of IA using the maximum a posteriori rule. Under the MAP rule, we assign the individual to the group of source populations for which the posterior source probability is maximal, with application of various minimum probability thresholds. To achieve the overarching goals above, we consider two diverse example applications, reanalyzing recently published data in light of simulation results. Finally, we make recommendations for specific methods based on their performance under various distributions of the ecological/phenotypic trait and genetic distance among populations. Although we draw heavily on Pacific salmon research, we emphasize the general applicability of our analyses and especially the diversity of genetic and non-genetic traits that can be examined. Our analysis is relevant to all marker classes. Applications are limited only by available baseline data for known-origin individuals. We expect increasing interest in our methods as those data become available for more taxa. We constructed two sets of known BKD infections rates among the six reporting groups, one in which the infection rates were positively correlated with genetic similarity among reporting groups, and a second set which was negatively correlated. In the positive case, we hypothesized that both methods would perform equally well, as any errors in assignment would be between reporting groups with similar infection rates. In the negative case, however, assignment errors would most likely occur between reporting groups with dissimilar infection rates, which would bias their estimation. A measure of genetic differentiation was computed for each pair of reporting groups. Genetic differentiation between population pairs, FST, was calculated with GENEPOP, version 4.1.0. The average FST among all unique pairs of populations in each pair of reporting groups was computed as a measure of differentiation.