BackgroundThere have been many efforts to develop efficient vaccines for the control of porcine reproductive and respiratory syndrome virus (PRRSV). Although inactivated PRRSV vaccines are preferred for their safety, they are weak at inducing humoral immune responses and controlling field PRRSV infection, especially when heterologous viruses are involved.ResultsIn all groups, the sample to positive (S/P) ratio of IDEXX ELISA and the virus neutralization (VN) titer remained negative until challenge. While viremia did not reduce in the vaccinated groups, the IDEXX-ELISA-specific immunoglobulin G increased more rapidly and to significantly greater levels 7 days after the challenge in all the vaccinated groups compared to the non-vaccinated groups (p < 0.05). VN titer was significantly different in the 106 PFU/mL PRRSV vaccine-inoculated and binary ethylenimine (BEI)-inactivated groups 22 days after challenge (p < 0.05). Consequently, the inactivated vaccines tested in this study provided weak memory responses with sequential challenge without any obvious active immune responses in the vaccinated pigs.ConclusionsThe inactivated vaccine failed to show the humoral immunity, but it showed different immune response after the challenge compared to mock group. Although the 106 PFU/mL-vaccinated and BEI-inactivated groups showed significantly greater VN titers 22 days after challenge, all the groups were already negative for viremia.

A major intracellular calcium (Ca) uptake pathway in both excitable and non-excitable eukaryotic cells is store-operated Ca entry (SOCE). SOCE is the process by which endoplasmic reticulum (ER)-stored Ca depletion leads to activation of plasma membrane Ca channels to provide a sustained increase in cytosolic Ca levels that mediate a plethora of physiological processes ranging from the immune response to platelet aggregation. Stromal interaction molecule-1 (STIM1) is the principal regulator of SOCE and responds to changes in ER stored Ca through luminal sensing machinery composed of EF-hand and SAM domains (EFSAM). The EFSAM domain can undergo N-glycosylation at Asn131 and Asn171 sites; however, the precise role of EFSAM N-glycosylation in the Ca sensing mechanism of STIM1 is unclear. By establishing a site-specific chemical approach to covalently linking glucose to EFSAM and examining α-helicity, thermal stability, three dimensional atomic-resolution structure, Ca binding affinity and oligomerization, we show that N-glycosylation of the EFSAM domain enhances the properties that promote STIM1 activation. This augmentation occurs through changes in structure localized near the Asn131 and Asn171 sites that together permeate through the protein core and lead to decreased Ca binding affinity, reduced stability and enhanced oligomerization. Congruently, Ca influx via SOCE in HEK293 cells co-expressing Orai1 and STIM1 was diminished when N-glycosylation was blocked by introducing Asn131Gln and Asn171Gln mutations. Collectively, our data suggests that N-glycosylation enhances the EFSAM destabilization-coupled oligomerization in response to ER Ca depletion thereby augmenting the role of STIM1 as a robust ON/OFF regulator of SOCE. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.

In order to prevent fatty acid deficiency and to supply enough energy, intravenous fat emulsion is necessary for parenteral nutrition in preterm neonates. However, parenteral administration of intravenous fat emulsion can induce lipid intolerance. The purpose of this study was to analyze risk factors for lipid intolerance in very low birth weight infants. This retrospective study included 80 preterm neonates whose birth weight was less than 1,500 g. Subjects were divided into 2 categories: those with a serum triglyceride level of ≥ 200 mg/dl (n = 33, 41%) and those with a serum triglyceride level of < 200 mg/dl (n = 47, 59%). We conducted logistic regression analysis using variables which were significant in univariate analysis. All statistical analyses were processed in SPSS version 19.0. Four risk factors for lipid intolerance were obtained through analysis of the electronic medical record. Lipid intolerance occurred more frequently in neonates with sepsis; those with a birth weight less than 1,000 g; those who was administered intravenous fat emulsion more than 2.6 g/kg/day; and those whose gestational age was less than 28 weeks. It is suggested that serum triglyceride levels should be closely monitored to prevent lipid intolerance in preterm neonates with the aforementioned characteristics.

As machine learning is increasingly used to make real-world decisions, recent research efforts aim to define and ensure fairness in algorithmic decision making. Existing methods often assume a fixed set of observable features to define individuals, but lack a discussion of certain features not being observed at test time. In this paper, we study fairness of naive Bayes classifiers, which allow partial observations. In particular, we introduce the notion of a discrimination pattern, which refers to an individual receiving different classifications depending on whether some sensitive attributes were observed. Then a model is considered fair if it has no such pattern. We propose an algorithm to discover and mine for discrimination patterns in a naive Bayes classifier, and show how to learn maximum-likelihood parameters subject to these fairness constraints. Our approach iteratively discovers and eliminates discrimination patterns until a fair model is learned. An empirical evaluation on three real-world datasets demonstrates that we can remove exponentially many discrimination patterns by only adding a small fraction of them as constraints.

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