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The enteric microbiota is characterised by a balance and composition that is unique to the host. It is important to understand the mechanisms through which the host can maintain the composition of the gut microbiota. MicroRNAs (miRNA) are implicated in intercellular communication and have been isolated from bodily fluids including stool. Recent findings suggest that miRNA produced by the host’s intestinal epithelial cells (IECs) participate in shaping the microbiota. To investigate whether miRNA expression was influenced by the gut microbiota we measured the expression of miRNAs expressed by intestinal epithelial cells in faeces. Specifically, we measured miRNA expression in faeces from germ-free (GF) and conventional mice and similarly in a rat model of antibiotic-mediated depletion of the gut microbiota control rats. In adult male GF and conventional mice and adult Sprague Dawley (SD) rats were treated with a combination of antibiotics for 8 weeks; total RNA was extracted from faecal pellets taken at week 0, 2, 4, 6 week 8 and the expression of let-7b-3p, miR-141-3p, miR-200a-3p and miR-1224-5p (miRNAs known to be expressed in IECs) were measured relative to U6 at each time point using qRT-PCR. In GF animals the expression of let-7b, miR-141 and miR-200a in faeces was lower compared to conventional mice. Following antibiotic-mediated depletion of gut microbiota, rats showed two divergent profiles of miRNA expression. Following two weeks of antibiotic treatment, the expression of let-7b and miR-1224 dropped significantly and remained low for the remainder of the study. The expression of miR-200a and miR-141 was significantly higher at week 2 than before antibiotic treatment commenced. Subsequently, the expression of miR-200a and miR-141 decreased at week 4 and continued to decrease at week 6. This data demonstrates that miRNAs can be used as an independent, non-invasive marker of microbial fluctuations along with gut pathology in the intestine.

The perception of visceral pain is a complex process involving the spinal cord and higher order brain structures. Increasing evidence implicates the gut microbiota as a key regulator of brain and behavior, yet it remains to be determined if gut bacteria play a role in visceral sensitivity. We used germ-free mice (GF) to assess visceral sensitivity, spinal cord gene expression and pain-related brain structures. GF mice displayed visceral hypersensitivity accompanied by increases in Toll-like receptor and cytokine gene expression in the spinal cord, which were normalized by postnatal colonization with microbiota from conventionally colonized (CC). In GF mice, the volumes of the anterior cingulate cortex (ACC) and periaqueductal grey, areas involved in pain processing, were decreased and enlarged, respectively, and dendritic changes in the ACC were evident. These findings indicate that the gut microbiota is required for the normal visceral pain sensation. DOI: http://dx.doi.org/10.7554/eLife.25887.001, eLife digest The human gut is home to over 100 trillion microbes collectively known as the gut microbiota. These microbes help us to digest food and absorb the nutrients effectively. A diverse and stable community of gut microbes is believed to be important for good health. Recently, it has also become clear that the microbiota can also influence the brain and how we behave. For example, many studies suggest that gut microbiota can alter how an individual perceives pain, but it is not clear how this works. Rodents are often used in experiments as models of human biology. One of the most frequently used rodent models in studies of gut microbes is the “germ-free” mouse. These mice grow up in laboratory environments that are completely free of microbes, making it possible to study how having no gut microbes affects the health and behaviour of the mice. Luczynski, Tramullas et al. used germ-free mice to study how the gut microbiota influences an animal’s sensitivity to pain. The experiments show that, compared to mice with normal gut microbiota, the germ-free mice were more sensitive to pain from internal organs especially the gut. These mice also produced larger amounts of specific proteins involved in immune responses, which contributed to the animal’s increased sensitivity to pain. Allowing the germ-free mice to be colonised with gut microbes could reverse these changes. The experiments also show that the germ-free mice had changes in the size of two areas of the brain involved in sensing pain: an area called the anterior cingulate cortex was smaller, while the periaqueductal grey region was enlarged. There were also differences in individual nerve cells within the anterior cingulate cortex compared to normal mice. The findings of Luczynski, Tramullas et al. reinforce the idea that the gut microbiota is involved in the sensation of pain from internal organs, and show that hypersensitivity to this form of pain can be reversed later in life by colonising the gut with microbes. Continuing to study the impact of microbes on this type of pain could aid the development of new therapies for the treatment of pain disorders in humans. DOI: http://dx.doi.org/10.7554/eLife.25887.002

Aims: Tissue transglutaminase (tTG) was recently identified as the major autoantigen in coeliac disease. The aim of this multicentre study was to evaluate the impact of a new immunoenzymatic assay for the detection of IgA anti-tGT antibodies. Methods: Seventy four Italian and French clinical laboratories participated in this study; anti-tTG IgA with an enzyme linked immunosorbent assay (ELISA) method using guinea pig liver extract as the coating antigen, anti-endomysium IgA autoantibodies (EMA), and total serum IgA were determined in 7948 patients, 1162 of whom had coeliac disease (737 untreated cases and 425 on a gluten free diet). A proportion of the sera were then sent to a reference laboratory for anti-tTG retesting with an ELISA method using recombinant human tTG antigen. Results: Seven thousand four hundred and fifty eight (93.8%) sera were EMA/antiguinea pig tTG concordant (positive or negative); 490 (6.2%) were non-concordant. The sensitivity of EMA and antiguinea pig tTG in the 737 untreated patients with coeliac disease was 92.1% and 94.8%, respectively, and the specificity was 99.8% and 99.2%, respectively. Retesting of the discordant sera showed that of the 162 sera classified as EMA negative/antiguinea pig tTG positive, only 49 were positive for human recombinant anti-tTG, and that 39 of these were also EMA positive. Furthermore, of the 36 sera classified as EMA positive/antiguinea pig tTG negative, only two were confirmed as EMA positive. Conclusions: The antiguinea pig tTG assay is more sensitive but less specific than EMA, whereas the antihuman recombinant tTG assay is far more specific and just as sensitive as antiguinea pig tTG. Testing for EMA presents considerable interpretative problems and is difficult to standardise.

3725 Background: Capecitabine and Irinotecan have different mechanisms of action and are both active in colorectal cancer (CRC). Capecitabine is activated by intratumoral thymidine phosphorylase and this enzyme may be up-regulated by irinotecan. The combination of these two drugs is tested in this multicenter phase II trial, the first of a new cooperative group: Brazilian Oncology Consortium (BOC CRC-001). Methods: A total of 37 pts with measurable metastatic CRC were included. 21men (57%) and 16 women (43%); median age 53.6 (23–74). Most pts were ECOG PS 0 29/35 (82%), 5% were PS 2. Tumor differentiation was GII in 75% and GIII/IV in 14% of the cases. Liver involvement was present in 65% of the pts. 13/37 (35%) of the pts had received previous adjuvant 5FU/LV. The treatment regimen included Capecitabine 1000mg/m2 PO twice daily for 14 days and Irinotecan 75mg/m2 IVover 90 min d1and 8. Cycles repeated every 3 weeks. Patients >65 years old received lower doses of both agents (750/60) and were required to h...

The diagnosis of Cow's Milk Protein Allergy was considered in 303 infants aged less than 1 year, who presented with one or more of the following symptoms: acute reaction related to cow's milk proteins (CMP) ingestion, severe colics, persisting vomiting, protracted diarrhea with or without blood and mucus, failure to thrive, eczema, respiratory symptoms, such as chronic rhinitis and wheezing. A diagnosis of CMPA was confirmed in 148 cases (60%): 125 relapsed on milk challenge, 23 were not challenged because of acute reactions at onset, presence of specific IgE (RAST and prick), and improvement on milk free diet. Familial atopy, familial history of CMPA and previous acute gastroenteritis were significantly more frequent in cases than in 191 age matched controls. Breast feeding was not more common or of longer duration in controls, compared to cases. Mean IgE serum levels were higher (46.3 U/ml) in cases than in controls (17 U/ml), while specific Cow's Milk Protein IgE were found in 71/148 cases (48%). 15 infants entered the study while on breast milk, because of the confirmed relation between their symptoms and CMP on the maternal diet. These infants had a higher prevalence of IgE mediated problems. All cases improved on a milk free diet but in 26 (17.8%) a further modification of the diet was required after the first prescription. Milk challenge was monitored by simple laboratory tests: all cases who had symptoms on challenge showed at least one test modification. Six infants, with no history of acute reaction, showed severe self-limited clinical symptoms at challenge.

α,β–Dehydrocurvularin (α,β–DC), 4,5,6,7–tetrahydro–11 ,13–dihydroxy–4–methyl–2H–3–benzoxacyclododecin–2,10(1H)-dione, was obtained by us as main constituent from Aspergillus aureofulgens1 in small quantities (16 mgll of culture broth). The compound shows the properties of α,β–DC described by other Authors [2, 3, 4]. This is the first time that α,β–DC was found as a metabolite of an Aspergillus species. Previously α,β–DC was isolated from Curvularia lunata [2], subsequently from Alternaria cucumarina and Stemphylium radicinum [3, 4]. Antibiotic activity: α,β–DC shows a weak activity (MIC 40 μg/ml) [5] against Gram–positive and Gram–negative bacteria (e.g. Bacillus subtilis, Staphylococcus aureus and Escherichia coli). Such an activity was not mentioned in previous works.

Background Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods Fifteen centres screened 17,201 students aged 6-15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 x 1000 (95% CI 3.79-5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 x 1000 (95% CI 4.57-6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.

Background Dialysis increases patient life expectancy but is associated with clinically severe and costly complications. Health and economic benefits could derive from postponing dialysis with a supplemented very low-protein diet (sVLPD). Methods An economic evaluation was conducted to compare benefits and costs of sVLPD versus dialysis in elderly CKD5 patients. Data from 57 patients aged >or=70 years, with glomerular filtration rate (GFR) 5-7 mL/min, previously participating in a clinical trial demonstrating non-inferior mortality and morbidity of starting sVLPD compared to dialysis treatment, were analysed: 30 patients were randomized to dialysis and 27 to sVLPD. A cost-benefit analysis was conducted, in the perspective of the National Health Service (NHS). Direct medical and non-medical benefits and costs occurring in 3.2 mean years of follow-up were quantified: time free from dialysis, cost of dialysis treatment, hospitalization, drugs, laboratory/instrumental tests, medical visits and travel and energy consumption to receive dialysis. Prices/tariffs valid in 2007 were used, with an annual discount rate of 5% applied to benefits and costs occurring after the first year. Sensitivity analyses were conducted to identify how estimates could vary in different contexts of applications. Results are reported as net benefit, expressed as mean euro/patient (patient-year). Results The opportunity to safely postpone initiation of dialysis of 1 year/patient on average translated into an economic benefit to the NHS, corresponding to 21 180 euro/patient in the first, 6500 euro/patient in the second and 682 euro/patient in the third year of treatment, with a significant net benefit in favour of sVLPD even in a worst-case hypothesis. Conclusion The initiation of sVLPD in elderly CKD5 subjects is a safe and beneficial strategy for these patients and allows them to gain economic resources that can be allocated to further health care investments.

Recent success in clinical trials supports the use of adeno-associated viral (AAV) vectors for gene therapy of retinal diseases caused by defects in the retinal pigment epithelium (RPE). In contrast, evidence of the efficacy of AAV-mediated gene transfer to retinal photoreceptors, the major site of inherited retinal diseases, is less robust. In addition, although AAV-mediated RPE transduction appears efficient, independently of the serotype used and species treated, AAV-mediated photoreceptor gene transfer has not been systematically investigated thus so far in large animal models, which also may allow identifying relevant species-specific differences in AAV-mediated retinal transduction. In the present study, we used the porcine retina, which has a high cone/rod ratio. This feature allows to properly evaluate both cone and rod photoreceptors transduction and compare the transduction characteristics of AAV2/5 and 2/8, the two most efficient AAV vector serotypes for photoreceptor targeting. Here we show that AAV2/5 and 2/8 transduces both RPE and photoreceptors. AAV2/8 infects and transduces photoreceptor more efficiently than AAV2/5, similarly to what we have observed in the murine retina. The use of the photoreceptor-specific rhodopsin promoter restricts transgene expression to porcine rods and cones, and results in photoreceptor transduction levels similar to those obtained with the ubiquitous promoters tested. Finally, immunological, toxicological and biodistribution studies support the safety of AAV subretinal administration to the large porcine retina. The data presented here on AAV-mediated transduction of the cone-enriched porcine retina may affect the development of gene-based therapies for rare and common severe photoreceptor diseases. © 2011 Macmillan Publishers Limited All rights reserved. Recent success in clinical trials supports the use of adeno-associated viral (AAV) vectors for gene therapy of retinal diseases caused by defects in the retinal pigment epithelium (RPE). In contrast, evidence of the efficacy of AAV-mediated gene transfer to retinal photoreceptors, the major site of inherited retinal diseases, is less robust. In addition, although AAV-mediated RPE transduction appears efficient, independently of the serotype used and species treated, AAV-mediated photoreceptor gene transfer has not been systematically investigated thus so far in large animal models, which also may allow identifying relevant species-specific differences in AAV-mediated retinal transduction. In the present study, we used the porcine retina, which has a high cone/rod ratio. This feature allows to properly evaluate both cone and rod photoreceptors transduction and compare the transduction characteristics of AAV2/5 and 2/8, the two most efficient AAV vector serotypes for photoreceptor targeting. Here we show that AAV2/5 and 2/8 transduces both RPE and photoreceptors. AAV2/8 infects and transduces photoreceptor more efficiently than AAV2/5, similarly to what we have observed in the murine retina. The use of the photoreceptor-specific rhodopsin promoter restricts transgene expression to porcine rods and cones, and results in photoreceptor transduction levels similar to those obtained with the ubiquitous promoters tested. Finally, immunological, toxicological and biodistribution studies support the safety of AAV subretinal administration to the large porcine retina. The data presented here on AAV-mediated transduction of the cone-enriched porcine retina may affect the development of gene-based therapies for rare and common severe photoreceptor diseases. Gene Therapy (2011) 18, 637-645; doi:10.1038/gt.2011.3; published online 17 March 2011