A review of the human vs. porcine female genital tract and associated immune system in the perspective of using minipigs as a model of human genital Chlamydia infection

International audienceAbstractSexually transmitted diseases constitute major health issues and their prevention and treatment continue to challenge the health care systems worldwide. Animal models are essential for a deeper understanding of the diseases and the development of safe and protective vaccines. Currently a good predictive non-rodent model is needed for the study of genital chlamydia in women. The pig has become an increasingly popular model for human diseases due to its close similarities to humans. The aim of this review is to compare the porcine and human female genital tract and associated immune system in the perspective of genital Chlamydia infection. The comparison of women and sows has shown that despite some gross anatomical differences, the structures and proportion of layers undergoing cyclic alterations are very similar. Reproductive hormonal cycles are closely related, only showing a slight difference in cycle length and source of luteolysing hormone. The epithelium and functional layers of the endometrium show similar cyclic changes. The immune system in pigs is very similar to that of humans, even though pigs have a higher percentage of CD4+/CD8+ double positive T cells. The genital immune system is also very similar in terms of the cyclic fluctuations in the mucosal antibody levels, but differs slightly regarding immune cell infiltration in the genital mucosa - predominantly due to the influx of neutrophils in the porcine endometrium during estrus. The vaginal flora in Göttingen Minipigs is not dominated by lactobacilli as in humans. The vaginal pH is around 7 in Göttingen Minipigs, compared to the more acidic vaginal pH around 3.5–5 in women. This review reveals important similarities between the human and porcine female reproductive tracts and proposes the pig as an advantageous supplementary model of human genital Chlamydia infection

Assessment of simultaneous reaction and diffusion in n-hexane hydroisomerization on Pt/H-ZSM-5 using Single Event MicroKinetics

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Kinetic modeling of pore mouth catalysis in the hydroconversion of n-octane on Pt-H-ZSM-22

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Aggregation state effects in shape-selective hydroconversion

A unified model for the description of vapor- and liquid-phase hydroconversion has been developed. The high isomer yield, which is typical for the shape selectivity exhibited by Pt/H-ZSM-22 at vapor-phase conditions, is still observed at liquid-phase conditions. However, the molar cracking yield is enhanced by at least 10 mol % when operating at liquid-phase conditions. The latter effect is mainly due to an increased physisorption competitiveness of lighter alkanes, which also results in enhanced cracking of lighter alkanes. The effect amounts to approximately 3 orders of magnitude for a difference of 2 in carbon number. These aggregation state effects are accounted for in the model through (i) liquid phase thermodynamic nonideality, (ii) destabilization of the physisorbed state by compression of the adsorbate by the bulk fluid, and (iii) carbenium ion stabilization by sorbent solvation by the bulk fluid. F-values of the order of 103 indicate the model's adequacy in describing the observed phenomena