Application of a pig ligated intestinal loop model for early Lawsonia intracellularis infection

<p>Abstract</p> <p>Background</p> <p>Porcine proliferative enteropathy in pigs is caused by the obligate, intracellular bacterium <it>Lawsonia intracellularis</it>. <it>In vitro </it>studies have shown close bacterium-cell interaction followed by cellular uptake of the bacterium within 3 h post inoculation (PI). However, knowledge of the initial <it>in vivo </it>interaction between porcine intestinal epithelium and the bacterium is limited. The aims of the present study were to evaluate the usefulness of a ligated small intestinal loop model to study <it>L. intracellularis </it>infections and to obtain information on the very early <it>L. intracellularis</it>-enterocyte interactions.</p> <p>Methods</p> <p>A ligated small intestinal loop model using three different <it>L. intracellularis </it>inocula was applied to 10-11-week-old pigs. The inocula were 1) wild type bacteria derived from overnight incubation of <it>L. intracellularis </it>bacteria from spontaneous disease, 2) crude vaccine bacteria (Enterisol^®Ileitis Vet), and 3) vaccine bacteria propagated in cell culture. The bacteria-enterocyte interaction was visualised using immunohistochemistry on specimens derived 1, 3 and 6 h PI respectively.</p> <p>Results</p> <p>Although at a low level, close contact between bacteria and the enterocyte brush border including intracellular uptake of bacteria in mature enterocytes was seen at 3 and 6 h PI for the vaccine and the propagated vaccine inocula. Interaction between the wild-type bacteria and villus enterocytes was scarce and only seen at 6 h PI, where a few bacteria were found in close contact with the brush border.</p> <p>Conclusions</p> <p>The ligated intestinal loop model was useful with respect to maintaining an intact intestinal morphology for up to 6 h. Furthermore, the study demonstrated that <it>L. intracellularis </it>interacts with villus enterocytes within 3 to 6 h after inoculation into intestinal loops and that the bacterium, as shown for the vaccine bacteria, propagated as well as non-propagated, was able to invade mature enterocytes. Thus, the study demonstrates the early intestinal invasion of <it>L. intracellularis in vivo</it>.</p

The coefficient of correction of effectiveness with the account of natural factors

The existing methods of determination of effectiveness don’t give the opportunity to emphasize the factors to the full extent. By which we can achieve the effect: the level of development of technologies, exploitation of natural resources, i,e. the damage to the environment etc. The economic damage, caused to the environment as a result of exploitation of natural resources and ecological violations at the given moment, doesn’t have a precise definition at the profound level. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/1280

Understanding the spread of de novo and transmitted macrolide-resistance in Mycoplasma genitalium.

Background The rapid spread of azithromycin resistance in sexually transmitted Mycoplasma genitalium infections is a growing concern. It is not yet clear to what degree macrolide resistance in M. genitalium results from the emergence of de novo mutations or the transmission of resistant strains. Methods We developed a compartmental transmission model to investigate the contribution of de novo macrolide resistance mutations to the spread of antimicrobial-resistant M. genitalium. We fitted the model to resistance data from France, Denmark and Sweden, estimated the time point of azithromycin introduction and the rates at which infected individuals receive treatment, and projected the future spread of resistance. Results The high probability of de novo resistance in M. genitalium accelerates the early spread of antimicrobial resistance. The relative contribution of de novo resistance subsequently decreases, and the spread of resistant infections in France, Denmark and Sweden is now mainly driven by transmitted resistance. If treatment with single-dose azithromycin continues at current rates, macrolide-resistant M. genitalium infections will reach 25% (95% confidence interval, CI [9-30]%) in France, 84% (95% CI [36-98]%) in Denmark and 62% (95% CI [48-76]%) in Sweden by 2025. Conclusions Blind treatment of urethritis with single-dose azithromycin continues to select for the spread of macrolide resistant M. genitalium. Clinical management strategies for M. genitalium should limit the unnecessary use of macrolides

Treng kyr i midtlaktasjon ekstra tilskot av E-vitamin?

Sjølv om α-tokoferolinnhaldet (39 mg/kg DM) i surfôr ikkje var spesielt høgt, var det tydelegvis nok når surfôropptaket var så høgt som i dette forsøket. Det er grunn til å revurdere tilrådinga om ekstra E-vitamin til mjølkekyr i midt- og seinlaktasjon