Investigations into the temporal development of epitheliocystis infections in brown trout: a histological study.

Epitheliocystis in Swiss brown trout (Salmo trutta) is a chlamydial infection, mainly caused by Candidatus Piscichlamydia salmonis and Candidatus Clavichlamydia salmonicola. To gain a better understanding of the temporal development of infections in wild brown trout, we investigated epitheliocystis infections during the course of the summer and autumn months of a single year (2015), and compared this to sampling points over the span of the years 2012-2014. The survey focused on tributaries (Venoge and Boiron) of the Rhone flowing in to Lake Geneva. When evaluated histologically, epitheliocystis infections were found throughout the period of investigation with the exception of the month of June. Fifty to 86 animals per sampling were investigated. Highest prevalence and infection intensities were seen in September. A correlation between epitheliocystis infection and water temperatures was not evident. Interyear comparison revealed consistent levels of prevalence and infection intensities in late summer. The absence of infections in June, combined with the consistent interyear results, indicates seasonal fluctuation of epitheliocystis infections in brown trout with a reservoir persisting during winter months from which infections can re-initiate each year. This could either be at levels below detection limits within the brown trout population itself or in an alternative host.

Viabilidad de las bacterias ácido lácticas (BAL) del yogur en el tracto gastrointestinal / Viability of the lactic-acid bacteria (LAB) of yogurth in the gastrointestinal tract

Son muchos los aspectos que pueden influir sobre la viabilidad de las bacterias ácido-lácticas (BAL) que se encuentran presentes en las leches fermentadas, ya que éstas se someten a grandes cambios tras la ingestión en su camino hacia el colon. El primer obstáculo que se encuentran las BAL es precisamente el mayor mecanismo de defensa del organismo frente a la mayoría de los microorganismos ingeridos: la secreción de jugos gástricos. La capacidad de las BAL para sobrevivir a los cambios de pH varía según la especie. Existen numerosos estudios en humanos y en animales de experimentación sobre la supervivencia de las BAL dentro del tracto gastrointestinal. La importancia de esta supervivencia radica en que una vez en el intestino las BAL puedan continuar desarrollando su actividad metabólica ejerciendo así efectos beneficiosos en el huésped, llegando a producir un aumento de la resistencia contra microorganismos patógenos, estimulación del sistema inmunológico, reducción de la sintomatología de la intolerancia a la lactosa, prevención de diarreas, reducción de las enzimas fecales relacionadas con el cáncer de colon y disminución del colesterol sérico entre otros (AU)

The adaptive response of the immune system to the particular malnutrition of eating disorders.

Despite the seriously undernourished state of patients with anorexia nervosa (AN) and bulimia nervosa (BN), controversial findings have been published regarding some aspects of the immune system that are otherwise impaired in more typical types of malnutrition, such as protein-energy malnutrition. In general, adaptation processes seem to occur enabling immune function to be preserved during long periods of the illness. However, cell-mediated immunity is usually altered in AN and BN as reflected by lymphocyte subset counts and the response to delayed hypersensitivity tests. Regarding the helper/cytotoxic T cell ratio (CD4:CD8), an immunological marker of the nutritional status, the results of our studies on AN and BN patients showed that the duration of the eating disorder and the time when appropriate treatment is achieved are likely contributors to the alteration of this ratio. Despite these findings, it has been repeatedly pointed out that anorexic patients seem to be free of common viral infections at least until the most advanced stages of debilitation. Some hypotheses that could explain the lack of infection symptoms are reviewed. Cytokines and the altered acute phase response to infection, as well as cortisol and leptin, are considered to be potential factors involved in the adaptation processes occurring in these syndromes. Further progress in the knowledge of the psychoneuroendocrine-immune interactions established in AN and BN will be relevant to the understanding of the aetiology and maintenance mechanisms of these pathologies.

Probiotics as a help in children suffering from malnutrition and diarrhoea.

Malnutrition is associated with a significant impairment of cell-mediated immunity, phagocyte function, immunoglobulin A concentrations and cytokine production. This situation-which is unfortunately very frequent in infants and children from developing countries-leads to a high risk of infection, and often to episodes of diarrhoea, hence aggravating the nutritional status. Fermented milks are known to exert a beneficial influence on the host's health. They act by modulating gut microflora, regulating any alteration of gut mucosa and stimulating immune response. A number of studies have shown that probiotics shorten the duration of diarrhoea and prevent recurrence of other episodes. Furthermore, probiotics can prevent diarrhoea from infection in infants with malnutrition. In addition, it has been shown that cytokines could be used as biological markers of both impaired immune system and the immune stimulation of probiotics. The aim of this review is to update the effect of fermented milks in situations of malnutrition and diarrhoea as a consequence of infection as well as the role of cytokines produced by fermented milks in these deficient conditions.

The effect of fermented milk on interferon production in malnourished children and in anorexia nervosa patients undergoing nutritional care.

For several years cytokine production has been associated with infections but it was not suspected that some types of food could also induce cytokines, even in a state of non-infection. Lactic bacteria can induce interferon (IFN) production in human healthy subjects, thus, a better protection against infections would be expected. Therefore, we planned to evaluate the effect of two diets including yoghurt or milk on IFN-gamma production during nutritional recovery in two different situations of malnutrition: (1) children with diarrhoea; and (2) patients with anorexia nervosa (AN). Both the diet including yoghurt of that including milk seemed to increase IFN-gamma production at the end of nutritional recovery in the malnourished children with diarrhoea. The significance of interferon production and the lymphocyte subset increase should be explored to know if a better resistance against pathogens is related to them. Regulation of intestinal absorption and moderate stimulation of interferon production make the yoghurt-based diet a good choice in the nutritional care of children. In the same way, an increase in the IFN-gamma production was observed in AN patients consuming yoghurt. This increase of IFN-gamma production could be considered a biological marker to detect the effect of probiotics on the immune response, especially in the improvement of a deficient nutritional status.