Citrobacter Infection and Wnt Signaling

Gut flora generally contributes to a healthy environment, but both commensal and pathogenic bacteria that influence the innate and adaptive immune responses can cause acute and/or chronic mucosal inflammation. Citrobacter rodentium is a member of the family of enteropathogens that provide an excellent in vivo model to investigate host?Cpathogen interactions in real time. It is the etiologic agent of transmissible murine colonic hyperplasia, and inflammation following C. rodentium infection is dependent upon the genetic background. Ongoing and completed studies in this model have established that Wnt/??-catenin, Notch, and phosphatidylinositol 3-kinase pathways regulate colonic crypt hyperplasia, whereas epithelial?Cstromal cross talk, mediated by MEK/ERK/nuclear factor ??B signaling, regulates inflammation and/or colitis in susceptible strains. The C. rodentium-induced hyperplastic state also increases the susceptibility to either mutagenic insult or in mice heterozygous for the Apc gene. The ability to modulate the host response to C. rodentium infection therefore provides an opportunity to delineate the mechanisms that determine mucosal hyperplasia, intestinal inflammation, and/or neoplasia as disease outcomes.     

Lost needle: a dilemma in robotic-assisted laparoscopic surgery

A case is presented where a needle was lost in the assistant’s port during a robotic-assisted radical prostatectomy. This complication generated a unique dilemma: whether or not to disengage the robot and search for the needle or to continue with the operation and look for the needle at the end of the operation.     

Sorghum Quality,Organic Matter Amendments,and Health: Farmers’ Perception in Burkina Faso,West Africa

In West Africa, many people suffer from micronutrient deficiencies. Current interventions have low chances of succeeding. Therefore, a food chain approach including local practices is proposed. This article takes local ecological, cultural, and socio-economic aspects into account through a household survey in northern Burkina in 2002. Farmers’ knowledge was compared with available scientific information. Organic matter production is a function of the number of animals owned and the availability of labor and equipment. Organic resources are allocated to various fields according to soil texture and the crop to be grown. Farmers were unable to link micronutrient deficiency in the soil directly to food quality and human health. However, they indicated that some disorders (e.g., fatigue in adults, stunted growth of children, anemia) are associated with a low level of micronutrients in the diet. For the application of organic amendments to be modified to improve grain yield and food quality in the Sahel, the relation between organic amendment and food quality must be better understood by both scientists and farmers.     

Immunoglobulin-like domain containing receptor 1 mediates fat-stimulated cholecystokinin secretion

Cholecystokinin (CCK) is a satiety hormone produced by discrete enteroendocrine cells scattered among absorptive cells of the small intestine. CCK is released into blood following a meal; however, the mechanisms inducing hormone secretion are largely unknown. Ingested fat is the major stimulant of CCK secretion. We recently identified a novel member of the lipoprotein remnant receptor family known as immunoglobulin-like domain containing receptor 1 (ILDR1) in intestinal CCK cells and postulated that this receptor conveyed the signal for fat-stimulated CCK secretion. In the intestine, ILDR1 is expressed exclusively in CCK cells. Orogastric administration of fatty acids elevated blood levels of CCK in wild-type mice but not Ildr1-deficient mice, although the CCK secretory response to trypsin inhibitor was retained. The uptake of fluorescently labeled lipoproteins in ILDR1-transfected CHO cells and release of CCK from isolated intestinal cells required a unique combination of fatty acid plus HDL. CCK secretion secondary to ILDR1 activation was associated with increased [Ca²⁺]_i, consistent with regulated hormone release. These findings demonstrate that ILDR1 regulates CCK release through a mechanism dependent on fatty acids and lipoproteins and that absorbed fatty acids regulate gastrointestinal hormone secretion.