Gluten-free diet and gut microbiome

As the only effective therapy against diagnosed celiac disease (CD), the gluten-free diet (GFD) has inevitable repercussion on the gut microbiome composition and functionality. Being the cause or the consequence of the disease, an altered homeostasis of the gut microbiome usually affects CD patients at diagnosis. After describing the main features of this altered physiological condition, this review defines the main nutritional aspects of the GFD and elucidates how this diet regimen does not fully restore the optimal gut microbiome composition and functionality. Unbalanced ratios between beneficial and potentially harmful bacteria are frequently present in fecal materials, biopsy specimens and saliva, used as ecological model systems to observe CD. Metabolome analyses also show how an altered microbiome synthesize different metabolite with respect to healthy conditions. The review concludes illustrating the current supplementations (biotics family), which fortify the GFD with the aim of restoring the homeostasis of the gut microbiome

A survey of the main technology, biochemical and microbiological features influencing the concentration of biogenic amines of twenty Apulian and Sicilian (Southern Italy) cheeses

Abstract Twenty Apulian and Sicilian cheeses were analysed for their concentrations of eight biogenic amines (BAs), free amino acids, pH, water activity, and subjected to microbiological characterisation. In addition, lactic acid bacteria isolated from cheeses were assayed for their capacity to generate BAs. Principal component analysis was performed to find the effect of different parameters on the distribution of the cheeses. Although short-ripened (≤30 d) cheeses did not show significant BA concentrations, the only BA showing high positive correlation with time of ripening was histamine. Concentration of histidine and, especially, percentage of histidine-decarboxylase bacteria presumably affected histamine concentration. High pH values were negatively correlated to the concentration of tyramine, putrescine, and cadaverine. Fifty percent of the cheeses contained at least one BA at potentially toxic concentrations. Unambiguous and ever-valid relations among parameters and BAs are difficult to determine, because BAs are the result of combined and varied factors

Vasoactive peptides in the luteolytic process activated by PGF2alpha in pseudopregnant rabbits at different luteal stages

To study the role of endothelial factors in luteal function, the dynamic profiles of genes for endothelin 1 (EDN1), its receptor subtypes, EDNRA and EDNRB, and angiotensin converting enzyme (ACE) were examined in corpora lutea (CL) obtained from rabbits on Days 4 and 9 of pseudopregnancy after prostaglandin (PG) 172a analogue (alfaprostol) treatment. The cell type distribution of EDN1 in the ovaries and its mechanisms of actions in vitro and in vivo were also studied. Positive immunostaining for EDN1 was localized in the luteal and endothelial cells, in granulosa cells of the follicles, and in the ovarian epithelium. The basal mRNA levels for EDNRA, EDNRB, and ACE were lower (P <= 0.01) in Day-4 CL than in Day-9 CL, whereas those for EDNi did not differ between these two time-points. On Day 4, the luteal EDN1, EDNRA, EDNRB, and ACE mRNA levels were similarly increased two-fold (P <= 0.01) 1.5 h after alfaprostol injection, and did not show further changes in the subsequent 24 h. On Day 9, alfaprostol challenge transiently up-regulated (P < 0.01) the luteal ACE transcripts at 1.5 h, and those of EDN1 at 1.5 h and 3 h, whereas the EDNRA and EDNR8 transcript levels remained unchanged during the course of luteal regression. EDN1 decreased (P < 0.01) progesterone release and increased (P <= 0.01) PGF2 alpha secretion and NOS activity via the PLC/PKC pathway in Day-9 CL, but not in Day-4 CL, cultured in vitro. EDN1-induced, but not alfaprostol-induced luteolysis, was blocked by cotreatment in vivo with the ACE antagonist captopril. These findings support the hypothesis that PGF2 alpha regulates luteolysis through intraluteal activation of the reninangiotensin/EDN1 systems in CL that have acquired luteolytic competence

Effects of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001 in IBS patients

Background: Irritable bowel syndrome (IBS) is a common gastrointestinal disorder, which still lacks effective therapy. We aimed to investigate the effects of a novel formulation of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001 with vitamin B6 (LBB) on symptoms, intestinal permeability, cultivable bacteria and metabolome in IBS subjects. Materials and methods: Twenty-five IBS patients (Rome IV criteria) (M:F = 8:17; age 48 years ± 11 SD) were randomized to treatment (LBB) or placebo (one month each) in a crossover randomized double-blind controlled trial. Symptoms, intestinal habits, disease severity, intestinal permeability and intestinal microbiota were analysed at 0, 30, 45 and 60 days. Results: Percentage decrease from baseline of abdominal pain (−48.8% vs −3.5%), bloating (−36.35% vs +7.35%) and severity of disease (−30.1% vs −0.4%) was significantly (P <.0001) greater with LBB than placebo, respectively. In IBS-D patients, the improvement from baseline of Bristol score was more consistent with LBB (from 6 ± 0.4 to 4.3 ± 1.1, P <.00001) than placebo (from 6.2 ± 0.7 to 5.3 ± 1.1, P =.04). In IBS-C patients, Bristol score tended to improve from baseline after LBB (2.6 ± 1.1 vs 3.2 ± 0.5, P =.06). LBB significantly improved the percentage of sucralose recovery (colonic permeability) (1.86 ± 0.1 vs 1.1 ± 0.2, P =.01). During treatment, presumptive lactic acid bacteria and bifidobacteria, relative abundance of propanoic, butanoic, pentanoic acids and hydrocarbons increased, while phenol decreased. Conclusions: The novel formulation of B. longum BB536 and L. rhamnosus HN001 with B6 vitamin improves symptoms and severity of disease, restores intestinal permeability and gut microbiota in IBS patients

Role of endothelin-1 system in the luteolytic process of pseudopregnant rabbits

The aim of this study was to better understand the role of the endothelin-1 (ET-1) system in the process of controlling the corpora lutea (CL) life span in rabbits. ET-1 (10 mug iv) administration at d 9 and 12 of pseudopregnancy induced a functional luteolysis within 24 h of injection, but it was ineffective at both d 4 and 6. Pretreatments with Bosentan, a dual ETA/ETB receptor antagonist, or cyclooxygenase ( COX) inhibitor blocked the luteolytic action of ET-1 but not that induced by prostaglandin F-2alpha (PGF(2alpha)). In CL cultured in vitro, ET-1 increased (P less than or equal to 0.01) both PGF(2alpha) production and luteal nitric oxide synthase activity but decreased (P less than or equal to 0.01) progesterone release. Addition of ETA receptor antagonist BQ123 or COX inhibitor blocked the ET-1 luteolytic effects. Positive staining for ET-1 receptors was localized in ovarian blood vessels, granulosa cells of large follicles, and luteal cells. Immunoblot analysis of ET-1 receptor protein revealed a strong band of approximately 48 kDa in d-9 CL. Up to d 6 of pseudopregnancy, ET-1 mRNA abundance in CL was poorly expressed but then increased (P less than or equal to 0.01) at d 9 and 13. ETA-receptor transcript increased (P less than or equal to 0.01) at d 6, remained at the same level up to d 13, and then declined to the lowest (P less than or equal to 0.01) levels at d 22. ETB-receptor mRNA increased (P less than or equal to 0.01) throughout the late-luteal stage from d 13 up to d 18. Our data suggest that the luteolytic action of ET-1 may be a result of PGF(2alpha) synthesis from both luteal and accessory cells, via the COX pathways

Developing a virtual reality environment for petrous bone surgery: a state-of-the-art review

The increasing power of computers has led to the development of sophisticated systems that aim to immerse the user in a virtual environment. The benefits of this type of approach to the training of physicians and surgeons are immediately apparent. Unfortunately the implementation of “virtual reality” (VR) surgical simulators has been restricted by both cost and technical limitations. The few successful systems use standardized scenarios, often derived from typical clinical data, to allow the rehearsal of procedures. In reality we would choose a system that allows us not only to practice typical cases but also to enter our own patient data and use it to define the virtual environment. In effect we want to re-write the scenario every time we use the environment and to ensure that its behavior exactly duplicates the behavior of the real tissue. If this can be achieved then VR systems can be used not only to train surgeons but also to rehearse individual procedures where variations in anatomy or pathology present specific surgical problems. The European Union has recently funded a multinational 3-year project (IERAPSI, Integrated Environment for Rehearsal and Planning of Surgical Interventions) to produce a virtual reality system for surgical training and for rehearsing individual procedures. Building the IERAPSI system will bring together a wide range of experts and combine the latest technologies to produce a true, patient specific virtual reality surgical simulator for petrous/temporal bone procedures. This article presents a review of the “state of the art” technologies currently available to construct a system of this type and an overview of the functionality and specifications such a system requires