Biomedical subjects

E Norin

Publications and source records attributed to E Norin.

At least 19 recordsLinked to original sources

PubMed2007

Parental perceptions of feeding practices in five European countries: an exploratory study.

OBJECTIVE: To gain an insight into parental perceptions of infant feeding practices in five European countries. DESIGN: An exploratory investigation using focus group discussions. Various aspects addressed included social and cultural setting for the consumption of food, infant feeding practice and behaviour, consumer health awareness and sources of information, and attitudes towards a healthy infant diet. SETTING: Focus group participants were recruited from centres in five countries, Germany, Italy, Scotland, Spain and Sweden, with three focus groups being conducted in each centre. SUBJECTS: A total of 108 parents with infants up to the age of 12 months participated in focus group discussions across these centres. METHODS: Focus groups were conducted with participants from centres in five countries. RESULTS: The majority of parents in this study chose to initiate breastfeeding and prepare infant food at home. Parents did not strictly adhere to infant feeding guidelines when introducing complementary foods into their infant's diets. There were cross-cultural differences in sources of information on infant feeding practice with the paediatrician in Germany, Italy and Spain. The health visitor in Scotland and the child welfare clinics in Sweden were the most popular sources. CONCLUSIONS: A number of cultural differences and similarities in attitudes towards infant feeding practice were revealed. This makes European wide approaches to promoting healthy infant feeding difficult as different infant feeding practices are influenced not only by parental perceptions but also by advice from health professionals and feeding guidelines. Further data need to be available on parents' attitudes and beliefs towards infant feeding practice to investigate further the rationale for differing beliefs and attitudes towards infant feeding practice. SPONSORSHIP: EU Fifth Framework QLRT 2002 02606.

Adult↗

PubMed2005

Gastrointestinal bacteria generate nitric oxide from nitrate and nitrite.

Denitrifying bacteria in soil generate nitric oxide (NO) from nitrite as a part of the nitrogen cycle, but little is known about NO production by commensal bacteria. We used a chemiluminescence assay to explore if human faeces and different representative gut bacteria are able to generate NO. Bacteria were incubated anaerobically in gas-tight bags, with or without nitrate or nitrite in the growth medium. In addition, luminal NO levels were measured in vivo in the intestines in germ-free and conventional rats, and in rats mono-associated with lactobacilli. We show that human faeces can generate NO after nitrate or nitrite supplementation. Lactobacilli and bifidobacteria generated much NO from nitrite, but only a few of the tested strains produced NO from nitrate and at much lower levels. In contrast, Escherichia coli, Bacteroides thetaiotaomicron, and Clostridium difficile did not produce significant amounts of NO either with nitrate or nitrite. NO generation in the gut lumen was also observed in vivo in conventional rats but not in germ-free rats or in rats mono-associated with lactobacilli. We conclude that NO can be generated by the anaerobic gut flora in the presence of nitrate or nitrite. Future studies will reveal its biological significance in regulation of gastrointestinal integrity.

Adult↗

PubMed2005

Birth-related increase in intracolonic hydrogen gas and nitric oxide as indicator of host-microbial interactions.

BACKGROUND: Bacterial colonization of the intestine early in life might have implications for allergy development. We studied early host-bacterial interactions in the gut by simultaneous measurements of hydrogen gas (H(2)) and faecal short chain fatty acid pattern (SCFAs), i.e. bacterial products, as well as of nitric oxide (NO), a marker of mucosal immune activation. METHODS: A novel minimally invasive technique was used for repeated measurements of luminal colonic H(2) and NO in 32 healthy newborn infants delivered vaginally or by Caesarean section. Luminal gas was sampled and analysed at five occasions: immediately after birth, day 1, days 3-5, 1 and 5-6 months after birth. RESULTS: Colonic H(2), NO and faecal SCFAs were undetectable at birth. The H(2) and SCFAs appeared within 24 h and continued to increase during the 6 months follow-up. Nitric oxide remained very low until 3-5 days after birth at which time it markedly increased. In some apparently healthy infants NO transiently reached levels similar to those seen in adults with inflammatory bowel disease. CONCLUSION: Intracolonic measurements of H(2) and NO may be useful to monitor the developmental colonization process as well as mucosal responses.

Aging↗

PubMed2005

Biochemical intestinal parameters in germ-free minipigs and rats and in ex-germ-free minipigs and rats monoassociated with Escherichia coli.

Intestinal contents of newborn and young germ-free minipigs and germ-free rats were investigated for the following biochemical parameters - conversion of cholesterol to coprostanol, degradation of beta-aspartylglycine, level of tryptic activity, formation of urobilinogen and the profile of short-chain fatty acids. Additionally, germ-free minipigs and germ-free rats were monoassociated with non-pathogenic strains of Escherichia coli and were investigated for the same biochemical parameters. The conversion of cholesterol to coprostanol, degradation of beta-aspartylglycine, tryptic activity and the short-chain fatty acid profile were similar to those found in previous studies in germ-free animals. Slightly higher amounts of urobilinogen than in the other species investigated so far were found in samples from germ-free and monoassociated minipigs. Except for the total amount of short-chain fatty acids in rats, monoassociation with E. coli did not alter any of the parameters either in the minipigs or in the rats.

Animals↗

PubMed2005

Gut microflora associated characteristics in children with celiac disease.

OBJECTIVES: The aim of the study was to investigate the metabolic function of intestinal microflora in children with celiac disease (CD) in order to find out if there is a deviant gut flora in CD patients compared to healthy controls. METHODS: The study group comprised children with CD, consecutively diagnosed according to current criteria given by the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition. Thirty-six children were studied at presentation, i.e., on a normal gluten-containing diet, with clinical symptoms and signs indicative of CD, positive celiac serology markers, and a small bowel biopsy showing severe enteropathy. Forty-seven patients were studied when they had been on a gluten-free diet (GFD) for at least 3 months. For comparison, a group of 42 healthy controls (HC) were studied. The functional status of the intestinal microflora was evaluated by gas-liquid chromatography of short chain fatty acids (SCFAs) in fecal samples. RESULTS: There was a significant difference between untreated CD children and HC as well as between treated CD children and HC regarding acetic, i-butyric, i-valeric acid, and total SCFAs. The propionic and n-valeric acids differed significantly between CD children on GFD and HC. Moreover, there was a strong correlation between i-butyric and i-valeric acids in all study groups. CONCLUSIONS: This is the first study of the SCFA pattern in fecal samples from children with CD. The results indicate that there is a difference in the metabolic activity of intestinal microbial flora in children with CD compared to that in HC. The finding of a different pattern of some SCFAs in celiacs both at presentation and during treatment with GFD indicates that it is a genuine phenomenon of CD not affected by either the diet, the inflammation, or the autoimmune status of the patient.

Biomarkers↗

PubMed2003

Influence of zinc bacitracin and Bacillus licheniformis on microbial intestinal functions in weaned piglets.

The influence of zinc bacitracin (ZB) and of Bacillus licheniformis on host microbial-related functions in young piglets was investigated by applying the concept of microflora-associated characteristics. Six biochemical parameters were determined before and after weaning in faecal samples from piglets in four litters having access to a diet containing ZB, to a diet containing B. licheniformis, to a diet with both additives, or to a diet with no additives, from 3 weeks of age. Statistically significant differences were found in three of the intestinal functions investigated: formation of short-chain fatty acids (at 7 and 10 weeks of age). degradation of mucin (at 7 and 10 weeks of age) and conversion of bilirubin to urobilins (at 7 weeks of age). We also found age-dependent influences on the formation of short-chain fatty acids, on conversion of cholesterol to coprostanol and on conversion of bilirubin to urobilins. We conclude that a functional approach is appropriate for measuring exogenous influence(s) on the microbial intestinal metabolisms in weaned piglets.

Animals↗

PubMed2003

A human flora-associated rat model of the breast-fed infant gut.

OBJECTIVES: Bacterial colonization of the infant gut may have important influences on the development of gastrointestinal, respiratory, and allergic disease. Early diet is a major determinant of the gut microflora. It is very difficult to carry out studies in human infants that can investigate the interaction of diet, flora, and mucosa. In this study we have developed an infant human flora-associated (IHFA) rat model to allow such investigation. METHODS: Germ-free infant rats were infected with fecal bacteria from exclusively breast-fed infants and were maintained on a modified infant formula for 8 weeks. The fecal and cecal contents were collected and compared with feces of breast-fed infants for bacterial populations, bacterial metabolites, and enzymes and for the ability to inhibit adhesion of pathogenic bacteria to human mucosal cells. RESULTS: The IHFA cecum and feces were dominated by lactic acid bacteria, Bifidobacterium, and lactobacilli, which were representative of the infant feces. The fecal short-chain fatty acid profile was dominated by acetic and lactic acid in a similar manner to human infant feces. Other bacterial metabolites were similar to those of the human infant. Rat intestinal samples were able to inhibit the adhesion of pathogens to mucosal cells, but to a lesser extent than the human samples. CONCLUSIONS: This IHFA infant model of the intestinal flora of the breast-fed infant is considered valid for studying the effect of diet on bacterial colonization and metabolism.

Animals↗

PubMed2003

A collection and treatment system for organic waste and wastewater in a sensitive rural area.

In the municipality of Sund, located in a sensitive rural area in Aland, a demonstration project is now carried out with the overall objective to move the most concentrated fractions of wastewater from the coastal area to a treatment plant situated close to arable land. Blackwater and greywater septic sludge from about twenty households and two tourist camps are treated together with energy rich organic material from a nearby potato-chip factory. The collection concept is based on the use of extremely efficient water-saving toilets, with separate systems for the blackwater and greywater in the households. The collected materials are co-treated in a batchwise aerobic thermophilic treatment process (wet composting process), where the materials reach at least 55 degrees C during a minimum of 10 hours. The dry matter content of the collected material was about 2%. After stabilisation and sanitation (by the temperature rise caused by microbial activity during the treatment process), the compost slurry is utilized as a liquid organic fertilizer on arable land.

Bacteria, Aerobic↗

PubMed2002

Biochemical intestinal parameters in pigs reared outdoors and indoors, and in germ-free pigs.

Intestinal microbial functions reflect cross-talk between a host and its flora, and external factors may influence these functions. The aim of this investigation was to follow the development of six biochemical microbial-related functions of piglets, raised outdoors (OPs) or indoors (IPs), from birth to slaughter age. The following parameters (microflora-associated characteristic; MAC) were consecutively measured at five different ages: production of short-chain fatty acids (SCFA), conversion of cholesterol to coprostanol and of bilirubin to urobilinogens, inactivation of trypsin, degradation of beta-aspartylglycine and of mucin. Additionally, four parameters (production of SCFA. conversion of cholesterol to coprostanol, inactivation of trypsin, degradation of beta-aspartylglycine) were investigated in faecal samples from germ-free minipigs. The differences in MAC patterns between OPs and IPs were most pronounced at 20 days of age. Differences were found in the total amount of SCFAs, proportions of the acetic, propionic and butyric acids, conversion of bilirubin to urobilinogens, degradation of faecal tryptic activity and degradation of mucin. The values found in the minipigs were within the range of a germ-free animal characteristic (GAC) pattern. Our results show that environmental factors influence the development of some intestinal microbial functions in pigs.

Animal Husbandry↗

PubMed2002

Increased enterocyte production in gnotobiotic rats mono-associated with Lactobacillus rhamnosus GG.

There is increasing scientific and commercial interest in using beneficial microorganisms (i.e., probiotics) to enhance intestinal health. Of the numerous microbial strains examined, Lactobacillus rhamnosus GG has been most extensively studied. Daily intake of L. rhamnosus GG shortens the course of rotavirus infection by mechanisms that have not been fully elucidated. Comparative studies with germfree and conventional rats have shown that the microbial status of an animal influences the intestinal cell kinetics and morphology. The present study was undertaken to study whether establishment of L. rhamnosus GG as a mono-associate in germfree rats influences intestinal cell kinetics and morphology. L. rhamnosus GG was easily established in germfree rats. After 3 days of mono-association, the rate of mitoses in the upper part of the small intestine (jejunum 1) increased as much as 14 and 22% compared to the rates in germfree and conventional counterparts, respectively. The most striking alteration in morphology was an increase in the number of cells in the villi. We hypothesis that the compartmentalized effects of L. rhamnosus GG may represent a reparative event for the mucosa.

Animals↗

PubMed2000

Toxins, butyric acid, and other short-chain fatty acids are coordinately expressed and down-regulated by cysteine in Clostridium difficile.

It was recently found that a mixture of nine amino acids down-regulate Clostridium difficile toxin production when added to peptone yeast extract (PY) cultures of strain VPI 10463 (S. Karlsson, L. G. Burman, and T. Akerlund, Microbiology 145:1683-1693, 1999). In the present study, seven of these amino acids were found to exhibit a moderate suppression of toxin production, whereas proline and particularly cysteine had the greatest impact, on both reference strains (n = 6) and clinical isolates (n = 28) of C. difficile (>99% suppression by cysteine in the highest toxin-producing strain). Also, cysteine derivatives such as acetylcysteine, glutathione, and cystine effectively down-regulated toxin expression. An impact of both cysteine and cystine but not of thioglycolate on toxin yield indicated that toxin expression was not regulated by the oxidation-reduction potential. Several metabolic pathways, including butyric acid and butanol production, were coinduced with the toxins in PY and down-regulated by cysteine. The enzyme 3-hydroxybutyryl coenzyme A dehydrogenase, a key enzyme in solventogenesis in Clostridium acetobutylicum, was among the most up-regulated proteins during high toxin production. The addition of butyric acid to various growth media induced toxin production, whereas the addition of butanol had the opposite effect. The results indicate a coupling between specific metabolic processes and toxin expression in C. difficile and that certain amino acids can alter these pathways coordinately. We speculate that down-regulation of toxin production by the administration of such amino acids to the colon may become a novel approach to prophylaxis and therapy for C. difficile-associated diarrhea.

Amino Acid Sequence↗

PubMed2000

Six intestinal microflora-associated characteristics in sport horses.

The aim of this study was to investigate 6 microflora-associated characteristics (MACs) in faecal samples from horses and to compare the results with baselines previously established in other mammals. A MAC is defined as any anatomical structure, physiological, biochemical or immunological characteristic in a host, which has been acted on by microorganisms. When the active microbes are absent, as in germ-free animals and healthy newborn organisms, the corresponding characteristic is defined as germ-free animal characteristic (GAC). The MACs studied were degradation of mucin, conversion of cholesterol to coprostanol and bilirubin to urobilinogens, inactivation of tryptic activity, degradation of beta-aspartylglycine and excretion of short-chain fatty acids. Five MACs were studied in 19 sport horses and the mucin pattern investigated in 25 other sport horses. Our results show that conversion of cholesterol to coprostanol was present in all horses, irrespective of diet. All horses also demonstrated excretion of urobilinogens; however, the values varied depending on diet. Mucin and beta-aspartylglycine were totally degraded, as occurs similarly in other animal species. Excretion of short-chain fatty acids was lower than values previously found in man, rats and pigs, and the level of faecal tryptic activity was low. Our results show that the MAC/GAC concept is as good in monogastric herbivores as in omnivores for investigations of endogenous and exogenous factors influencing the intestinal ecosystem(s). Therefore, use of the MAC/GAC concept has a potential significance for future studies on functions related to the microflora.

Animals↗

PubMed2000

Influence of bacitracin on microbial functions in the gastrointestinal tract of horses.

This study investigated the influence of zinc bacitracin on the intestinal flora of horses. The functionally active intestinal flora was examined in 6 horses during treatment with zinc bacitracin. Utilising gas chromatography, spectrophotometry, gel electrophoresis and paper chromatography, samples were analysed on biochemical markers reflecting the action of parts of the intestinal flora. The following 5 flora-related functions were studied in faecal samples and intestinal samples from different sections of the hindgut: conversion of cholesterol to coprostanol and of bilirubin to urobilinogens, degradation of mucin and of beta-aspartylglycine and inactivation of tryptic activity. Conversion to coprostanol, conversion to urobilinogens and degradation of mucin were affected by treatment of zinc bacitracin and conversion to coprostanol was most sensitive. All functions were normalised in a short time, in contrast to man and rats. Differences in environmental exposures are probably the reason for a more rapid normalisation of the intestinal flora functions in horses.

Animals↗

PubMed1999

The effect of faecal enema on five microflora-associated characteristics in patients with antibiotic-associated diarrhoea.

BACKGROUND: Patients with antibiotic-associated diarrhoea (AAD) show significant disturbances in short-chain fatty acid pattern. In the present study five more microflora-associated characteristics (MACs) were investigated before and after administration of an enema containing faecal microflora from a healthy person on a Western diet. METHODS: The functions of the microflora were determined with gas chromatography, electrophoresis, and spectrophotometry. RESULTS: The conversion of cholesterol to coprostanol and the concentration of urobilinogen and trypsin were significantly reduced in comparison with healthy persons. The pattern of mucin was altered, but beta-aspartylglycine remained the same as in healthy persons. Enema treatment influenced these functions to different extents. CONCLUSION: Most MACs were significantly disturbed in patients with AAD. Administration of a human faecal enema modified these changes and relieved diarrhoea, usually within 4 days.

Adult↗

PubMed1998

Faecal short-chain fatty acids in patients with antibiotic-associated diarrhoea, before and after faecal enema treatment.

BACKGROUND: Antibiotic-associated diarrhoea (AAD) may range from mild disturbances to severe pseudomembranous colitis. Many antibiotics affect several intestinal microflora-associated characteristics, such as short-chain fatty acid (SCFA) pattern. In the present study we investigated SCFAs in 31 patients on admittance to the hospital for severe AAD. Nine patients were followed up more extensively after they had received an enema containing faecal microflora from a healthy person on a Western diet. METHODS: Faecal SCFAs were determined by gas chromatography. The enema was characterized before use. RESULTS: AAD patients showed significant disturbances in faecal SCFA pattern. Clinically, most enema-treated patients recovered within days and had no relapses within 18 months. CONCLUSIONS: Intestinal microflora showed great disturbances, and the amounts of SCFAs were reduced, although the diarrhoea was not related to total amount SCFAs. Administration of a faecal enema resulted in the clinical recovery of most patients with severe diarrhoea within 4 days.

Adult↗

PubMed1994

Abnormal colonic microbial function in patients with rheumatoid arthritis.

The aim of this study was to examine the microflora-associated characteristics (MACs) of faecal samples of patients with rheumatoid arthritis (RA) and to evaluate the actions of sulphasalazine (SASP) on these MACs. The conversion of cholesterol to coprostanol, the production of urobilinogen, the degradation of faecal tryptic activity (FTA) and of beta-aspartylglycine were measured in faecal samples from 19 patients treated with SASP and 21 patients not treated with this medication. A control group of 21 healthy subjects was sex- and age-matched with the untreated patients. The conversion of cholesterol to coprostanol showed a bimodal distribution. The frequency of high converters in patients without SASP treatment was higher than in healthy subjects (p < 0.05). Treatment with SASP markedly increased the FTA and reduced the urobilinogen values, as compared to the untreated patients (p < 0.05). Beta-aspartylglycine was not found in any faecal samples. The results indicate that patients with RA have an abnormal formation of coprostanol, which is ascribed to alterations in the function of the Eubacteria species. In patients with RA, SASP treatment induces disturbances in the metabolism of the microflora.

Aged↗

PubMed1990

The function of the intestinal microflora in patients with ulcerative colitis before and after colectomy.

The function of the intestinal microflora was studied in patients with ulcerative colitis before and after colectomy. The following six microflora-associated characteristics (MACs) were investigated: formation of coprostanol and urobilinogen; degradation of mucin, water-soluble protein, and beta-aspartylglycine; and presence of faecal tryptic activity. In 12 unoperated patients without sulphasalazine as maintenance therapy the six MACs were similar to those in normal subjects. In 12 unoperated patients receiving sulphasalazine the formation of coprostanol and urobilinogen was significantly lower (p less than 0.01 and p less than 0.001, respectively) and the level of faecal tryptic activity was significantly higher (p less than 0.01) than in normal subjects. The functional capacity of the microflora in operated patients treated by colectomy combined with one of four surgical procedures (ileorectal anastomosis, ileoanal anastomosis with pelvic pouch, Kock's continent ileostomy, or conventional ileostomy) was disturbed with regard to all six MACs. The disturbance was most pronounced in patients with conventional ileostomy.

Adult↗

PubMed1986

In vivo metabolism of leukotriene C4 in germ-free and conventional rats. Fecal excretion of N-acetylleukotriene E4.

[5,6,8,9,11,12,14,15-3H8]Leukotriene C4 was subcutaneously injected into rats. Substantial amounts of the administered radioactivity were excreted in feces of germ-free and conventional animals during a 72-h period (78 and 64%, respectively). Analyses of fecal extracts by high performance liquid chromatography showed eight radioactive components for each type of animal. One metabolite amounted to 4.6% of the injected radioactivity in germ-free and 0.6% in conventional rats. Its chemical structure, 5-hydoxy-6-S-(2-acetamido-3-thiopropionyl)-7,9-trans-11,14-c is-eicosatetraenoi c acid (N-acetylleukotriene E4) was determined by ultraviolet spectroscopy, fast atom bombardment mass spectrometry, chemical and enzymatic transformations, and confirmed by chemical synthesis. Another metabolite (2.7% of the administered radioactivity in germ-free and 0.5% in conventional rats) was characterized as the 11-trans isomer of the former metabolite. The pathway of formation of these compounds appears to be analogous to the pathway of mercapturic acid biosynthesis.

Animals↗