Mycoplasma‐like organisms (MLOs) were detected by fluorescence microscopy in a number of pear cultivars and pear seedlings growing under a range of different conditions. In the cultivar Conference, MLOs were consistently associated with symptoms of Parry's disease, a decline‐like disease of young trees with quince rootstocks. MLO‐free pear seedlings rapidly became infected when they were planted outside. Experimental transmission of MLOs to pear seedlings and Conference trees was achieved using pear psyllids, caught outside or raised on infected plants under controlled conditions. Conference trees in an orchard trial remained free from the severe spring symptoms of Parry's disease when they were protected from feeding insects during spring of the previous year. MLOs were graft transmissible, but were not perpetuated by the standard propagation practices of budding or grafting when quince rootstocks were used. Parry's disease appears to be similar to pear decline, an MLO‐induced disease well established in several other parts of the world. It is suggested that Parry's disease should be referred to as pear decline.
Background
Diet is a potential factor that could influence the pathogenesis and activity of Inflammatory Bowel Disease(IBD). Soluble fibre is the best way to generate short-chain fatty acids such as butyrate, which has anti-inflammatory effects. Around 1/3 of Crohn’s disease (CD) patients will present with stricturing disease, most frequently in the terminal ileum. These patients often follow a very low-residue diet. CD patients present significant changes in the structure of their microbiota with a decreased prevalence of butyrate-producing bacteria such as Clostridiales species, particularly Faecalibacterium prausnitzii. Depletion of F. prausnitzii might be further enhanced in patients with a very low-residue diet. The aim of this study was to evaluate the effect of a nutritional supplement enriched with soluble fibre on the abundance of F. prausnitzii in stricturing CD.
Methods
We performed a single arm, pilot trial in CD patients with ileal stricturing disease who followed a very low-residue diet as assessed by a dietician. The fibre-enriched nutritional supplement (reg#26.06141/BA-72556) consisted of a 200ml vanilla-flavoured shake that included 3.4 gr of soluble fibre, omega-3 and oleic fatty acids. Patients received 2 supplements per day for 6 weeks, and were followed for 6 months. We obtained frozen faecal samples at time-points 0, 3, 6, 12 and 24 weeks. Total bacteria and F. prausnitzii counts were assessed by qPCR. Weight, BMI, CD activity index (CDAI), CRP, fatty acids, urine F2-isoprostanes and faecal calprotectin were also determined. Tolerance, palatability and acceptability of the supplement were assessed with validated questionnaires at weeks 3 and 6.
Results
Ten patients were included in the study with a median age of 38 [36–50] years, 60% were male, median BMI 25.2 [24.3–28.4] and 40% were current smokers. Six patients completed the 6 weeks of the supplement. Two patients did not receive the supplement because they underwent ileocecal resection, 1 patient was lost to follow-up and 1 patient dropped-out early because of poor palatability of the supplement. At baseline, all patients had F. prausnitzii levels below 109 CFU/g (median 2.02 × 106). Supplement intake did not significantly increase F. prausnitzii levels (p = 0.73) and had no effect on CDAI, CRP, urine F2-isoprostanes or faecal calprotectin. Most usual complaints associated with the supplement were abdominal bloating and flatulence.
Conclusion
CD patients with structuring disease and who follow a very low-residue diet have a markedly reduced abundance of F. prausnitzii. Intake of a 6.8 g/day fibre-enriched nutritional supplement was unable to significantly increase F. prausnitzii abundance in these patients. Fibre supplement was not associated with adverse events.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.