The type II secretion system and its ubiquitous lipoprotein substrate, SsIE are required for biofilm formation and virulence of enteropathogenic escherichia coli

Enteropathogenic Escherichia coli (EPEC) is a major cause of diarrhea in infants in developing countries. We have identified a functional type II secretion system (T2SS) in EPEC that is homologous to the pathway responsible for the secretion of heat-labile enterotoxin by enterotoxigenic E. coli. The wild-type EPEC T2SS was able to secrete a heat-labile enterotoxin reporter, but an isogenic T2SS mutant could not. We showed that the major substrate of the T2SS in EPEC is SslE, an outer membrane lipoprotein (formerly known as YghJ), and that a functional T2SS is essential for biofilm formation by EPEC. T2SS and SslE mutants were arrested at the microcolony stage of biofilm formation, suggesting that the T2SS is involved in the development of mature biofilms and that SslE is a dominant effector of biofilm development. Moreover, the T2SS was required for virulence, as infection of rabbits with a rabbit-specific EPEC strain carrying a mutation in either the T2SS or SslE resulted in significantly reduced intestinal colonization and milder disease.

Capecitabine and oral cyclophosphamide : a novel oral treatment combination for advanced cancer

Background: This dose escalation study assessed feasibility of a totally oral chemotherapy regimen using cyclophosphamide and capecitabine. The rationale for this combination was based on the observation that preclinical models of cyclophosphamide up-regulated tumor thymidine phosphorylase and increased the activation of capecitabine. Methods: Eligible patients with advanced cancer were treated with oral cyclophosphamide and capecitabine on a 28-day cycle. If no dose limiting toxicities (DLT) were encountered during the first two treatment cycles, the next patient group was assigned to the next highest dose level until the maximum tolerable dose (MTD) was determined. Results: Twenty-seven patients entered treatment. The majority of non-DLT were grades 1 and 2. DLT experienced in the first 8-week observation period were grade 3 diarrhea (one patient, level III) and grade 3 emesis (two patients, level V). MTD was observed at level 5, 1331 mg/m2/day capecitabine days 1–28 with 125 mg/m2/day cyclophosphamide days 1–14 of the 28-day cycle. The recommended phase II dose is therefore 1331 mg/m2/day capecitabine with 100 mg/m2/day cyclophosphamide. The best response evaluation showed four partial responses (breast, colon, ovary and pancreas). Conclusion: Cyclophosphamide and capecitabine can be combined at their full oral single agent dose with promising tolerability and activity.

Randomised controlled trials in child health in developing countries: trends and lessons over 11 years.

Using a uniform systematic approach annually, we reviewed 1553 publications from randomised controlled trials in child health in developing countries published between July 2002 and June 2013. There were annual increases in such publications, from 38 in the 12 months to July 2003 to over 200 in each of 2012 and 2013. These trials involved children in 76 developing countries. Studies of nutrition (366 publications, 23.6%) and malaria (336 publications, 21%) predominated. 79% of nutrition trials have been of micronutrients (288 publications), with comparatively few publications related to macronutrient interventions or complimentary feeding (48 publications) or measures to improve breast feeding (20 publications). Trials of malaria have involved a comprehensive range of treatment and preventive strategies and have heralded the implementation of new interventions as routine health strategies, and reductions in malaria in each affected country in the world in the last decade. There have been a relatively small number of trials of interventions for treatment or prevention of acute respiratory infection (98 publications, 6.3%), neonatal health (64 publications, 4.1%) and tuberculosis in children (26 publications, 1.7%). In the last 5 years there has been increasing focus on non-communicable diseases such as asthma and allergy, obesity, diabetes and cardiac disease, and behavioural-developmental disorders. Mental health conditions have received little attention (21 publications, 1.4% of publications). There is increasing research activity and capacity in child health in developing countries. Some areas have been the subject of a large amount of research, and have led to the design and implementation of effective public health interventions and reduced disease burdens, while in other areas comprehensive approaches and the systematic application of research findings have been lacking.

Investigation into the role of potentially contaminated feed as a source of the first-detected outbreaks of porcine epidemic diarrhea in Canada

In January 2014, approximately 9 months following the initial detection of porcine epidemic diarrhea (PED) in the USA, the first case of PED was confirmed in a swine herd in south-western Ontario. A follow-up epidemiological investigation carried out on the initial and 10 subsequent Ontario PED cases pointed to feed as a common risk factor. As a result, several lots of feed and spray-dried porcine plasma (SDPP) used as a feed supplement were tested for the presence of PEDV genome by real-time RT-PCR assay. Several of these tested positive, supporting the notion that contaminated feed may have been responsible for the introduction of PEDV into Canada. These findings led us to conduct a bioassay experiment in which three PEDV-positive SDPP samples (from a single lot) and two PEDV-positive feed samples supplemented with this SDPP were used to orally inoculate 3-week-old piglets. Although the feed-inoculated piglets did not show any significant excretion of PEDV, the SDPP-inoculated piglets shed PEDV at a relatively high level for ≥9 days. Despite the fact that the tested PEDV genome positive feed did not result in obvious piglet infection in our bioassay experiment, contaminated feed cannot be ruled out as a likely source of this introduction in the field where many other variables may play a contributing role.

Site and mechanism of the colokinetic action of the ghrelin receptor agonist, HM01

Background It has been recently demonstrated that the ghrelin receptor agonist, HM01, caused defecation in rats that were treated to provide a model for the constipation of Parkinson's disease. HM01 significantly increased fecal output and increased Fos activity in neurons of the hypothalamus and hindbrain, but not in the spinal defecation center. Other ghrelin agonists act on the defecation center. Methods Receptor pharmacology was examined in ghrelin receptor (GHSR1a) transfected cells. Anesthetized rats were used to investigate sites and mechanisms of action. Key Results HM01 activated rat GHSR1a at nanomolar concentrations and was antagonized by the GHSR1a antagonist, YIL781. HM01, intravenous, was potent to activate propulsive colorectal contractions. This was prevented by pelvic nerve section and by intravenous YIL781, but not by spinal cord section rostral to the defecation centers. Direct intrathecal application of HM01 to the defecation center at spinal level L6-S1 initiated propulsive contractions of the colorectum. Conclusions & Inferences HM01 stimulates GHSR1a receptors on neurons in the lumbosacral defecation centers to cause propulsive contractions and emptying of the colorectum. It has greater potency when given systemically, compared with other GHSR1a agonists.

A ghrelin receptor agonist is an effective colokinetic in rats with diet-induced constipation

Background Despite constipation being a common problem, the treatments that are available have side effects and are only partly effective. Recent studies show that centrally penetrant ghrelin receptor agonists cause defecation in humans and other species. Here, we describe some features of a rat model of low fiber-induced constipation, and investigate the effectiveness of the ghrelin agonist, capromorelin. Methods Rats were given low-fiber diets for 5 weeks. Their colorectal responsiveness to distension and to a behavioral test, water avoidance and colon histology were compared to those of rats on a standard diet. Key Results After the low-fiber diet, distension of the colon produced fewer propulsive contractions, behaviorally induced defecation was reduced, and the lining of the colorectum was inflamed. However, capromorelin was similarly effective in causing defecation in constipated and non-constipated rats. Conclusions & Inferences Low-fiber diet in rats produces a constipation phenotype, characterized by reduced responsiveness of the colorectum to distension and to a behavioral stimulus of defecation, water avoidance. The effectiveness of capromorelin suggests that centrally penetrant ghrelin receptor stimulants may be effective in treating constipation.

Phytochemicals and biofunctional properties of buckwheat: a review

A growing trend for nutraceutical and gluten-free cereal-based products highlights the need for development of new products. Buckwheat is one of the potential candidates for such products and the present paper reviews the functional and nutraceutical compounds present in common buckwheat (Fagopyrum esculentum) and tartary buckwheat (Fagopyrum tataricum). The vital functional substances in buckwheat are flavonoids, phytosterols, fagopyrins, fagopyritols, phenolic compounds, resistant starch, dietary fibre, lignans, vitamins, minerals and antioxidants, which make it a highly active biological pseudocereal. Cholesterol-lowering effects that lessen the problems of constipation and obesity are important health benefits that can be achieved through the functional substances of buckwheat.