No abstract

Excessive alcohol intake can alter the gut microbiota, which may underlie the pathophysiology of alcohol-related diseases. We examined gut microbiota composition and functions in patients with alcohol overconsumption for >10 years, compared to a control group of patients with a history of no or low alcohol intake. Faecal microbiota composition was assessed by 16S rRNA sequencing. Gut microbiota functions were evaluated by quantification of short-chain fatty acids (SCFAs) and predictive metagenome profiling (PICRUSt). Twenty-four patients, mean age 64.8 years (19 males), with alcohol overconsumption, and 18 control patients, mean age 58.2 years (14 males) were included. The two groups were comparable regarding basic clinical variables. Nutritional assessment revealed lower total score on the screening tool Mini Nutritional Assessment, lower muscle mass as assessed by handgrip strength, and lower plasma vitamin C levels in the alcohol overconsumption group. Bacteria from phylum Proteobacteria were found in higher relative abundance, while bacteria from genus Faecalibacterium were found in lower relative abundance in the group of alcohol overconsumers. The group also had higher levels of the genera Sutterella, Holdemania and Clostridium, and lower concentration and percentage of butyric acid. When applying PICRUSt to predict the metagenomic composition, we found that genes related to invasion of epithelial cells were more common in the group of alcohol overconsumers. We conclude that gut microbiota composition and functions in patients with alcohol overconsumption differ from patients with low consumption of alcohol, and seem to be skewed into a putative pro-inflammatory direction.

Fifteen healthy old people mean age 84 years (range 80-91 years), were examined to assess the effect of advanced age on the microecology of the upper gastrointestinal tract. Twelve of 15 (80%) were hypochlorhydric with pH 6-6 (0.3) (mean (SEM) and a mean bacterial count of 108 colony forming units (CFU) per ml (range 105-10") in fasting gastric aspirate. Normochlorhydric subjects had low counts (610' CFU/ml). The microbial flora was dominated by viridans streptococci, coagulase negative staphylococci, and Haemophilus sp. Only one subject harboured significant concentrations of Gram negative bacilli with Escherichia coli (10'5 CFUIml) and Klebsiella (104`). Strict anaerobes were not found. The total concentration of short chain fatty acids in gastric aspirate was 10.6 (2.9) mmolIl (mean (SEM). Absence of significant, intraluminal fermentation of xylose to CO2 was shown by the '4C-d Xylose breath test, and ambulatory manometry showed preserved fasting motility pattern of the small intestine. Serum immunoglobulins were normal. Advanced age is accompanied by fasting hypochlorhydria and colonisation with mainly Gram positive flora in the upper gut. Other factors than old age and fasting hypochlorhydria are required for colonisation with Gram negative bacilli. (Gut 1992; 33: 1331-1337 Ageing is accompanied by an increasing prevalence of gastritis'2 and declining output of gastric acid,'3 whereas contradictory findings have been reported for gastric emptying.'415 It is currently believed that absence of gastric acid can lead to microbial growth, including that of Gram negative bacilli, in the upper gut.'6 As the clinical consequences of bacterial overgrowth are associated with presence of these species, and anaerobes in particular,'6 age related hypochlorhydria may represent a pathogenetic factor in the elderly. Reports of bacterial overgrowth without a blind loop in the elderly have brought this issue to current interest,'7 and the need for studies on intestinal flora and factors regulating microbial growth in ageing has recently been emphasised. 18 This prospective study examined gastric pH, microbial flora, and metabolic markers in the upper gastrointestinal tract of healthy old (>80 years) people.

Bile protein assays are complicated due to interference by other bile substances. In the present study we describe a microtiter plate method for the purification and quantification of bile proteins. The method is based on addition of acetonitrile in three steps to reconstituted freeze-dried bile, followed by ethanol washing of the precipitated proteins. Finally, protein in the precipitate is quantitated by two-point colour development using micro BCA reagents. Overall recoveries of protein in reconstituted bile spiked with exogenous protein (Seronorm) ranged from 91.0% (coefficient of variation; CV = 7.0%) to 97.1% (CV = 2.4%) by recoveries of 125I-Fibrinogen and 125I-Albumin. Bile pigments were largely removed during precipitation and washing, as verified by high pressure liquid chromatography (HPLC). Preferably the samples should be freeze-dried initially, as this lowered the blank readings. Two-point colour development with the BCA reagents were identical for standards assayed directly and standards added to protein depleted bile, and processed through all steps. Hence, no interference by either residual bile constituents nor the reagents upon the BCA protein assay could be detected. Standard curves ranged from 0.05 to 5.0 gl-1 (r > 0.98). Within day reproducibility (n = 15) was 7.8% (CV) and day to day (n = 10) was 12.1% (CV). Mean protein concentration in common duct bile from 30 patients was 1.20 gl-1 (range 0.34-3.87 gl-1). The method appears suitable for assay of bile protein, requires only limited sample volumes and allows processing of many samples within a short time.

Late radiation enteropathy (LRE) is a serious disorder, and therapeutic progress has thus far been hampered by insufficient understanding of the pathogenesis. This prospective study addresses whether alterations in proximal intestinal motility can predict the clinical severity of this disorder. Forty-one consecutive patients with chronic abdominal complaints after radiotherapy for gynecological cancer were examined by prolonged ambulatory manometry. Twenty-seven healthy adults served as controls. Impaired fasting motility was found in 12 of 41 patients (29%), and attenuated postprandial motor response after a liquid-solid meal was seen in 10 of 41 patients (24%). Postprandial delay of the migrating motor complex (MMC) was a good predictor of the degree of malnutrition (Cox regression, P < 0.01), and intensity of the MMC and postprandial motility index explained 69% (P < 0.001, multiple regression) of the variability in degree of malnutrition, assessed by weight loss and serum albumin level. The typical presentation of severe LRE was clinical symptoms suggesting intestinal pseudoobstruction, malnutrition, failure of a liquid-solid meal to induce postprandial motility, and delayed initiation and reduced intensity of MMC during nocturnal fasting. Prolonged ambulatory manometry was useful for detection of dysmotility in patients with symptoms of LRE and impaired motility of proximal small intestine seems to be a key factor in the pathogenesis of severe LRE.