Alcoholic liver disease progresses through several stages of tissue damage, from simple steatosis to alcoholic hepatitis, fibrosis, or cirrhosis. Alcohol also affects the intestine, increases intestinal permeability and changes the bacterial microflora. Liver disease severity correlates with levels of systemic bacterial products in patients, and experimental alcoholic liver disease is dependent on gut derived bacterial products in mice. Supporting evidence for the importance of bacterial translocation comes from animal studies demonstrating that intestinal decontamination is associated with decreased liver fibrogenesis. In addition, mice with a gene mutation or deletion encoding receptors for either bacterial products or signaling molecules downstream from these receptors, are resistant to alcohol-induced liver disease. Despite this strong association, the exact molecular mechanism of bacterial translocation and of how changes in the intestinal microbiome contribute to liver disease progression remains largely unknown. In this review we will summarize evidence for bacterial translocation and enteric microbial changes in response to alcoholic liver injury and chronic alcoholic liver disease. We will further describe consequences of intestinal dysbiosis on host biology. We finally discuss how therapeutic interventions may modify the gastrointestinal microflora and prevent or reduce alcoholic liver disease progression.
Yan, Arthur W; Schnabl, Bernd
Human intestinal microbiota create a complex polymicrobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO). SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacteriostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insufficiency, immunodeficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, fistulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Non-invasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be complex, addressing all causes, symptoms and complications, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO. PMID:20572300
Bures, Jan; Cyrany, Jiri; Kohoutova, Darina; Förstl, Miroslav; Rejchrt, Stanislav; Kvetina, Jaroslav; Vorisek, Viktor; Kopacova, Marcela
A total of 89 patients with alcoholic cirrhosis and 40 healthy subjects were included in a study to assess the prevalence of intestinal bacterial overgrowth and to analyze its relationship with the severity of liver dysfunction, presence of ascites, and development of spontaneous bacterial peritonitis (SBP). Bacterial overgrowth was measured by means of a breath test after ingestion of glucose.
F. Casafont Morencos; G. de las Heras Castano; L. Martín Ramos; Maria J. López Arias; F. Ledesma; F. Pons Romero
Objectives: Small intestinal bacterial overgrowth is defined as an abnormally high bacterial population level in the small intestine. Intestinal motor dysfunction associated with hypothyroidism could predispose to bacterial overgrowth. Luminal bacteria could modulate gastrointestinal symptoms and interfere with levothyroxine absorp- tion. The aims of the present study were to assess the prevalence and clinical pattern of bacterial overgrowth in patients
Ernesto Cristiano Lauritano; Anna Lisa Bilotta; Maurizio Gabrielli; Emidio Scarpellini; Andrea Lupascu; Antonio Laginestra; Marialuisa Novi; Sandra Sottili; Michele Serricchio; Giovanni Cammarota; Giovanni Gasbarrini; Alfredo Pontecorvi; Antonio Gasbarrini
Alcoholic liver disease (ALD) encompasses hepatic steatosis, which may progress to alcoholic hepatitis, fibrosis, and cirrhosis. It remains a leading cause of morbidity and mortality in the US and worldwide. The severity of liver disease correlates with plasma levels of bacterial products in patients, and experimental ALD depends on the level of gut derived bacterial products in rodents. Since intestinal decontamination and deficiency of bacterial product receptors or their downstream signaling molecules protect from alcohol-induced liver disease, bacterial translocation (BT), qualitative, and quantitative changes of the enteric microbiome are considered as being of fundamental importance in the pathogenesis of ALD. Recent enhancements in diagnostic technologies provide a better insight into these shifts. This review highlights vital events in ALD such as BT, the importance of Toll-like receptor (TLR) signaling, intestinal bacterial overgrowth (IBO), and changes in the intestinal microbiome. Furthermore, a treatment trial section of patients reviews possible future options of therapy for ALD modifying the enteric microbiome.
Hartmann, Phillipp; Chen, Wei-Chung; Schnabl, Bernd
The small intestinal bacterial overgrowth (SIBO) is defined by the presence in the proximal part of the intestine of a bacterial population and qualitatively abnormal. It is necessary to distinguish the "non-symptomatic" SIBO and the "symptomatic" SIBO responsible for a chronic diarrhoea and/or of a malabsorption syndrome. The main factor encouraging the intervening of a SIBO is the stasis of the intestinal juice. The gold standard test to confirm the diagnosis of SIBO is the jejunal bacteriological intubation, but it is about a trying and expensive method. It is currently supplanted by the respiratory test to hydrogen after ingestion of glucose that is simple, no invasive and little expensive. The treatment usually consists on the repeated administration of antibiotics and nutritional support. PMID:11458610
The intestinal mucus layer protects the epithelium from noxious agents, viruses, and pathogenic bacteria present in the gastrointestinal tract. It is composed of mucins, predominantly mucin (Muc) 2, secreted by goblet cells of the intestine. Experimental alcoholic liver disease requires translocation of bacterial products across the intestinal barrier into the systemic circulation, which induces an inflammatory response in the liver and contributes to steatohepatitis. We investigated the roles of the intestinal mucus layer, and in particular Muc2, in development of experimental alcohol-associated liver disease in mice. We studied experimental alcohol-induced liver disease, induced by the Tsukamoto-French method (which involves continuous intragastric feeding of an isocaloric diet or alcohol) in wild-type and Muc2(-/-) mice. Muc2(-/-) mice showed less alcohol-induced liver injury and steatosis than developed in wild-type mice. Most notably, Muc2(-/-) mice had significantly lower plasma levels of lipopolysaccharide than wild-type mice after alcohol feeding. In contrast to wild-type mice, Muc2(-/-) mice were protected from alcohol-associated microbiome changes that are dependent on intestinal mucins. The antimicrobial proteins regenerating islet-derived 3 beta and gamma were expressed at significantly higher levels in the jejunum of Muc2(-/-) mice fed the isocaloric diet or alcohol compared with wild-type mice. Consequently, Muc2(-/-) mice showed increased killing of commensal bacteria and prevented intestinal bacterial overgrowth. Conclusion: Muc2(-/-) mice are protected from intestinal bacterial overgrowth and dysbiosis in response to alcohol feeding. Subsequently, lower amounts of bacterial products such as endotoxin translocate into the systemic circulation, decreasing liver disease. PMID:23408358
Hartmann, Phillipp; Chen, Peng; Wang, Hui J; Wang, Lirui; McCole, Declan F; Brandl, Katharina; Stärkel, Peter; Belzer, Clara; Hellerbrand, Claus; Tsukamoto, Hidekazu; Ho, Samuel B; Schnabl, Bernd
Background & Aims Intestinal dysbiosis and bacterial translocation is common in patients with advanced liver disease, and there is strong evidence that the translocation of bacteria and their products across the epithelial barrier drives experimental liver disease progression. The aims of our study were to investigate dynamics of bacterial translocation and changes in the enteric microbiome in early stages of liver disease. Methods Cholestatic liver injury was induced by ligation of the common bile duct (BDL) and toxic liver injury by injection of carbon tetrachloride (CCl4) in mice. Results Increased intestinal permeability and bacterial translocation occurred one day following liver injury in both disease models. This was accompanied by decreased intestinal expression of the tight junction protein occludin. Although BDL resulted in a rapid onset of intestinal bacterial overgrowth, bacterial overgrowth was observed in mice injected with CCl4 only in advanced stages of liver fibrosis. To further assess the qualitative changes in the intestinal microbiome, massively parallel pyrosequencing of 16S rRNA genes revealed minor microbial changes following BDL, while CCl4 administration resulted in a relative abundance of Firmicutes and Actinobacteria compared with oil injected mice. Four different liver disease models (cholestasis, toxic, alcohol, obesity) show few similarities in their intestinal microbiome. Conclusions Acute liver injury is associated with an early onset of increased intestinal permeability and bacterial translocation that precede changes in the microbiome. The enteric microbiome differs with respect to the etiology of liver disease.
Fouts, Derrick E.; Torralba, Manolito; Nelson, Karen E.; Brenner, David A.; Schnabl, Bernd
Numerous bacterial species inhabit the lumen of the human intestine. The epithelial cells that line the intestinal barrier\\u000a are in direct contact with many of these species and have developed sophisticated strategies to prevent bacterial invasion\\u000a of host tissue beyond simply providing a physical blockade. Intestinal epithelial cells (IECs) possess receptors that are\\u000a capable of recognizing bacterial products, and engagement
Bryan P. Hurley; Beth A. McCormick
Infections, sepsis and multiple organ failure syndrome are associated with high morbidity and mortality in human and experimental small bowel transplantation (SBTx). These complications are attributed to bacterial translocation demonstrated in animal and human studies. Bacterial translocation (BT) is defined as the passage of viable bacteria from the intestinal lumen to other tissues or organs. BT has been associated with different clinical and experimental situations, hemorrhagic shock, trauma, bowel obstruction, immunodepression, total parenteral nutrition, antibiotics. Although BT has been investigated in several small and large animal models of SBTx, precise information on the mechanisms involved are not available. It is possible that the operative procedure by itself may promote BT for the interaction of a number of factors such as preservation, ischemia/reperfusion, abnormal motility, lymphatic disruption and aberrant systemic venous drainage, acute or chronic rejection and antibiotic therapy. Furthermore, the potent immunosuppressive therapy used in these patients may augment the deleterious effects caused by BT. In this review we examined the existing literature concerning BT with particular regard to intestinal transplantation, to better understand the alterations in the symbiotic relationship between immunocompromised host and his gut microflora after SBTx. PMID:10812777
Sileri, P; Rastellini, C; Dicuonzo, G; Gaspari, A; Benedetti, E; Cicalese, L
Parkinson's disease is associated with gastrointestinal motility abnormalities favoring the occurrence of local infections. The aim of this study was to investigate whether small intestinal bacterial overgrowth contributes to the pathophysiology of motor fluctuations. Thirty-three patients and 30 controls underwent glucose, lactulose, and urea breath tests to detect small intestinal bacterial overgrowth and Helicobacter pylori infection. Patients also underwent ultrasonography to evaluate gastric emptying. The clinical status and plasma concentration of levodopa were assessed after an acute drug challenge with a standard dose of levodopa, and motor complications were assessed by Unified Parkinson's Disease Rating Scale-IV and by 1-week diaries of motor conditions. Patients with small intestinal bacterial overgrowth were treated with rifaximin and were clinically and instrumentally reevaluated 1 and 6 months later. The prevalence of small intestinal bacterial overgrowth was significantly higher in patients than in controls (54.5% vs. 20.0%; P?=?.01), whereas the prevalence of Helicobacter pylori infection was not (33.3% vs. 26.7%). Compared with patients without any infection, the prevalence of unpredictable fluctuations was significantly higher in patients with both infections (8.3% vs. 87.5%; P?=?.008). Gastric half-emptying time was significantly longer in patients than in healthy controls but did not differ in patients based on their infective status. Compared with patients without isolated small intestinal bacterial overgrowth, patients with isolated small intestinal bacterial overgrowth had longer off time daily and more episodes of delayed-on and no-on. The eradication of small intestinal bacterial overgrowth resulted in improvement in motor fluctuations without affecting the pharmacokinetics of levodopa. The relapse rate of small intestinal bacterial overgrowth at 6 months was 43%. © 2013 Movement Disorder Society. PMID:23712625
Fasano, Alfonso; Bove, Francesco; Gabrielli, Maurizio; Petracca, Martina; Zocco, Maria Assunta; Ragazzoni, Enzo; Barbaro, Federico; Piano, Carla; Fortuna, Serena; Tortora, Annalisa; Di Giacopo, Raffaella; Campanale, Mariachiara; Gigante, Giovanni; Lauritano, Ernesto Cristiano; Navarra, Pierluigi; Marconi, Stefano; Gasbarrini, Antonio; Bentivoglio, Anna Rita
Alcohol acts as a teratogen in the fetus,resulting in prenatal or postnatal growth failure,characteristic facial dysmorphic features, and centralnervous system dysfunction. The toxic effects of alcohol on the developing brain are well recognized,but gastrointestinal neuropathy has not been describedin fetal alcohol syndrome (FAS). Five children with FASpresented in infancy with signs and symptoms suggestive of chronic intestinal pseudoobstruction. Theywere not
E. Vasiliauskas; D. A. Piccoli; A. F. Flores; C. Di Lorenzo; P. E. Hyman
Small intestinal bacterial overgrowth was originally defined in the context of an overt malabsorption syndrome and diagnostic tests were developed and validated accordingly. More recently, the concept of intestinal contamination with excessive numbers of bacteria, especially those of colonic type, has been extended beyond the bounds of frank maldigestion and malabsorption to explain symptomatology in disorders as diverse as irritable bowel syndrome, celiac sprue and nonalcoholic fatty liver disease. Owing to a lack of consensus with regard to the optimal diagnostic criteria (the 'gold standard') for the diagnosis of bacterial overgrowth, the status of these new concepts is unclear. This review sets out to critically appraise the various diagnostic approaches that have been taken and are currently employed to diagnose small intestinal bacterial overgrowth. PMID:19210115
Abu-Shanab, Ahmed; Quigley, Eamonn Mm
More than two thirds of the world's infants and chil- dren live in less developed countries, often in conditions in which the unavailability of potable water and sanita- tion and of refrigeration for foods fosters the transmis- sion of enteric pathogens. In such areas, bacterial enteric pathogens are common causes of infant diarrhea, dysen- tery in toddlers, and enteric (typhoid
Myron M. Levine
Thiamin is essential for normal cellular functions, and its deficiency leads to a variety of clinical abnormalities. Humans and other mammals obtain the vitamin via intestinal absorption. The intestine is exposed to two sources of thiamin, a dietary and a bacterial (i.e., normal microflora of the large intestine) source. Chronic alcohol consumption is associated with thiamin deficiency, which is caused (in part) by inhibition in intestinal thiamin absorption. However, little is known about the physiological and molecular aspects of the intestinal thiamin uptake process that are affected by chronic alcohol use. To address these issues, we used rats fed an alcohol-liquid diet and human intestinal epithelial HuTu-80 cells chronically exposed to ethanol as model systems. The results showed that chronic alcohol feeding to rats led to a significant inhibition in carrier-mediated thiamin transport across both the jejunal brush-border membrane and basolateral membrane domains. This was associated with a significant reduction in level of expression of thiamin transporter-1 (THTR-1), but not THTR-2, at the protein and mRNA levels. Level of expression of the heterogenous nuclear RNA of THTR-1 in the intestine of alcohol-fed rats was also decreased compared with their pair-fed controls. Chronic alcohol feeding also caused a significant inhibition in carrier-mediated thiamin uptake in rat colon. Studies with HuTu-80 cells chronically exposed to ethanol also showed a significant inhibition in carrier-mediated thiamin uptake. This inhibition was associated with a reduction in level of expression of human THTR-1 and THTR-2 at the protein, mRNA, and transcriptional (promoter activity) levels. These studies demonstrate that chronic alcohol feeding inhibits intestinal thiamin absorption via inhibition of the individual membrane transport event across the polarized absorptive epithelial cells. Furthermore, the inhibition is, at least in part, mediated via transcriptional mechanism(s).
Subramanya, Sandeep B.; Subramanian, Veedamali S.
Thiamin is essential for normal cellular functions, and its deficiency leads to a variety of clinical abnormalities. Humans and other mammals obtain the vitamin via intestinal absorption. The intestine is exposed to two sources of thiamin, a dietary and a bacterial (i.e., normal microflora of the large intestine) source. Chronic alcohol consumption is associated with thiamin deficiency, which is caused (in part) by inhibition in intestinal thiamin absorption. However, little is known about the physiological and molecular aspects of the intestinal thiamin uptake process that are affected by chronic alcohol use. To address these issues, we used rats fed an alcohol-liquid diet and human intestinal epithelial HuTu-80 cells chronically exposed to ethanol as model systems. The results showed that chronic alcohol feeding to rats led to a significant inhibition in carrier-mediated thiamin transport across both the jejunal brush-border membrane and basolateral membrane domains. This was associated with a significant reduction in level of expression of thiamin transporter-1 (THTR-1), but not THTR-2, at the protein and mRNA levels. Level of expression of the heterogenous nuclear RNA of THTR-1 in the intestine of alcohol-fed rats was also decreased compared with their pair-fed controls. Chronic alcohol feeding also caused a significant inhibition in carrier-mediated thiamin uptake in rat colon. Studies with HuTu-80 cells chronically exposed to ethanol also showed a significant inhibition in carrier-mediated thiamin uptake. This inhibition was associated with a reduction in level of expression of human THTR-1 and THTR-2 at the protein, mRNA, and transcriptional (promoter activity) levels. These studies demonstrate that chronic alcohol feeding inhibits intestinal thiamin absorption via inhibition of the individual membrane transport event across the polarized absorptive epithelial cells. Furthermore, the inhibition is, at least in part, mediated via transcriptional mechanism(s). PMID:20448146
Subramanya, Sandeep B; Subramanian, Veedamali S; Said, Hamid M
OBJECTIVES--To examine the microflora of the upper small intestine in patients with seropositive rheumatoid arthritis (RA) using a combination of microbial cultivation and tests for microbial metabolic activity. METHODS--Twenty five patients with seropositive RA, 12 achlorhydric control subjects, and 11 control subjects with normal gastric acid secretion were investigated. Disease activity was evaluated in the patients with RA by three different indices. Eight (32%) of the patients with RA had hypochlorhydria or achlorhydria. The acid secretory capacity was determined with pentagastrin stimulation. A modified Crosby capsule was used to obtain biopsy specimens and samples of intestinal fluid from the proximal jejunum; aerobic and anaerobic microbial cultivation of mucosal specimens/intestinal fluid was carried out, and gas production and microflora associated characteristics in jejunal fluid were determined. Additionally, a bile acid deconjugation breath test was performed. RESULTS--Subjects with at least one of the following findings were considered to have bacterial overgrowth: positive bile acid deconjugation test; growth of Enterobacteriaceae; positive gas production; or low tryptic activity. By these criteria half of the patients with RA with hypochlorhydria or achlorhydria and half of the achlorhydric controls had bacterial overgrowth. Thirty five per cent of the patients with RA with normal gastric acid secretion had bacterial overgrowth compared with none of the normal controls. Disease activity indices and rheumatoid factor titres were significantly higher in patients with RA with bacterial overgrowth than in those without. CONCLUSIONS--A high frequency of small intestinal bacterial overgrowth was found in patients with RA; it was associated with a high disease activity and observed in patients with hypochlorhydria or achlorhydria and in those with normal acid secretion.
Henriksson, A E; Blomquist, L; Nord, C E; Midtvedt, T; Uribe, A
OBJECTIVES:Current treatment for small intestinal bacterial overgrowth (SIBO) is based on courses of broad-spectrum antibiotics. No data concerning SIBO recurrence are available. The aims of the present study were to investigate SIBO recurrence as assessed by glucose breath test (GBT) after antibiotic treatment and conditions associated to SIBO recurrence.METHODS:Eighty consecutive patients affected by SIBO and decontaminated by rifaximin (1,200 mg
Ernesto C. Lauritano; Maurizio Gabrielli; Emidio Scarpellini; Andrea Lupascu; Marialuisa Novi; Sandra Sottili; Giovanna Vitale; Valentina Cesario; Michele Serricchio; Giovanni Cammarota; Giovanni Gasbarrini; Antonio Gasbarrini
Background: Small intestinal bacterial overgrowth (SIBO) has been proposed to be common in irritable bowel syndrome (IBS), with altered small-bowel motility as a possible predisposing factor.Aim: To assess the prevalence of SIBO, by culture of small-bowel aspirate, and its correlation to symptoms and motility in IBS.Methods: 162 patients with IBS who underwent small-bowel manometry and culture of jejunal aspirate were
Iris Posserud; Per-Ove Stotzer; Einar S Bjo?rnsson; Hasse Abrahamsson; Magnus Simre?n
We have shown that alcohol increases Caco-2 intestinal epithelial cell monolayer permeability in vitro by inducing the expression of redox-sensitive circadian clock proteins CLOCK and PER2 and that these proteins are necessary for alcohol-induced hyperpermeability. We hypothesized that alcohol metabolism by intestinal Cytochrome P450 isoform 2E1 (CYP2E1) could alter circadian gene expression (Clock and Per2), resulting in alcohol-induced hyperpermeability. In vitro Caco-2 intestinal epithelial cells were exposed to alcohol, and CYP2E1 protein, activity, and mRNA were measured. CYP2E1 expression was knocked down via siRNA and alcohol-induced hyperpermeability, and CLOCK and PER2 protein expression were measured. Caco-2 cells were also treated with alcohol or H?O? with or without N-acetylcysteine (NAC) anti-oxidant, and CLOCK and PER2 proteins were measured at 4 or 2 h. In vivo Cyp2e1 protein and mRNA were also measured in colon tissue from alcohol-fed mice. Alcohol increased CYP2E1 protein by 93% and enzyme activity by 69% in intestinal cells in vitro. Alcohol feeding also increased mouse colonic Cyp2e1 protein by 73%. mRNA levels of Cyp2e1 were not changed by alcohol in vitro or in mouse intestine. siRNA knockdown of CYP2E1 in Caco-2 cells prevented alcohol-induced hyperpermeability and induction of CLOCK and PER2 proteins. Alcohol-induced and H?O?-induced increases in intestinal cell CLOCK and PER2 were significantly inhibited by treatment with NAC. We concluded that our data support a novel role for intestinal CYP2E1 in alcohol-induced intestinal hyperpermeability via a mechanism involving CYP2E1-dependent induction of oxidative stress and upregulation of circadian clock proteins CLOCK and PER2. PMID:23660503
Forsyth, Christopher B; Voigt, Robin M; Shaikh, Maliha; Tang, Yueming; Cederbaum, Arthur I; Turek, Fred W; Keshavarzian, Ali
Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent and treat diseases associated with gut-derived bacterial products and disorders associated with gut leakiness. Indeed, "probiotic"Lactobacillus rhamnosus has been successfully used to treat alcohol-induced liver injury in rats. However, the mechanism of action involved in the potential beneficial effects of L. rhamnosus in alcohol liver injury is not known. We hypothesized that probiotics could preserve normal barrier function in an animal model of ALD by preventing alcohol-induced oxidative stress and thus prevent the development of hyperpermeability and subsequent alcoholic steatohepatitis (ASH). Male Sprague-Dawley rats were gavaged with alcohol twice daily (8 gm/kg) for 10 weeks. In addition, alcoholic rats were also treated with once daily gavage of either 2.5 x 10(7) live L. rhamnosus Gorbach-Goldin (LGG) or vehicle (V). Intestinal permeability (baseline and at 10 weeks) was determined using a sugar bolus and GC analysis of urinary sugars. Intestinal and liver tissues were analyzed for markers of oxidative stress and inflammation. In addition, livers were assessed histologically for severity of ASH and total fat (steatosis). Alcohol+LGG (ALC+LGG)-fed rats had significantly (P< or =.05) less severe ASH than ALC+V-fed rats. L. rhamnosus Gorbach-Goldin also reduced alcohol-induced gut leakiness and significantly blunted alcohol-induced oxidative stress and inflammation in both intestine and the liver. L. rhamnosus Gorbach-Goldin probiotic gavage significantly ameliorated ASH in rats. This improvement was associated with reduced markers of intestinal and liver oxidative stress and inflammation and preserved gut barrier function. Our study provides a scientific rationale to test probiotics for treatment and/or prevention of alcoholic liver disease in man. PMID:19251117
Forsyth, Christopher B; Farhadi, Ashkan; Jakate, Shriram M; Tang, Yueming; Shaikh, Maliha; Keshavarzian, Ali
OBJECTIVE:Infections are regarded as a major complication and an important cause of death in cirrhotics. Alcohol is a predisposing factor to infections in such patients. This study was undertaken to compare the frequency and evolution of bacterial infection among alcoholic and nonalcoholic cirrhotics.METHODS:To observe this relationship, we retrospectively studied a cohort of 382 cirrhotic inpatients, 201 of whom were alcoholic
Heitor Rosa; Américo O Silvério; Rafael F Perini; Cláudia B Arruda
Serratia marcescens is an entomopathogenic bacterium that opportunistically infects a wide range of hosts, including humans. In a model of septic injury, if directly introduced into the body cavity of Drosophila, this pathogen is insensitive to the host's systemic immune response and kills flies in a day. We find that S. marcescens resistance to the Drosophila immune deficiency (imd)-mediated humoral response requires the bacterial lipopolysaccharide O-antigen. If ingested by Drosophila, bacteria cross the gut and penetrate the body cavity. During this passage, the bacteria can be observed within the cells of the intestinal epithelium. In such an oral infection model, the flies succumb to infection only after 6 days. We demonstrate that two complementary host defense mechanisms act together against such food-borne infection: an antimicrobial response in the intestine that is regulated by the imd pathway and phagocytosis by hemocytes of bacteria that have escaped into the hemolymph. Interestingly, bacteria present in the hemolymph elicit a systemic immune response only when phagocytosis is blocked. Our observations support a model wherein peptidoglycan fragments released during bacterial growth activate the imd pathway and do not back a proposed role for phagocytosis in the immune activation of the fat body. Thanks to the genetic tools available in both host and pathogen, the molecular dissection of the interactions between S. marcescens and Drosophila will provide a useful paradigm for deciphering intestinal pathogenesis.
Nehme, Nadine T; Liegeois, Samuel; Kele, Beatrix; Giammarinaro, Philippe; Pradel, Elizabeth; Hoffmann, Jules A; Ewbank, Jonathan J; Ferrandon, Dominique
Background\\/Aims: Gastrointestinal (GI) symptoms are common among patients with chronic renal failure (CRF). The pathogenesis of these symptoms is probably multifactorial. Our aims were to assess gastric and small intestinal motility and the prevalence of small intestinal bacterial overgrowth (SIBO) in order to clarify possible pathophysiological mechanisms behind these symptoms in CRF patients. Methods: Twenty-two patients with CRF, 12 with
Hans Strid; Magnus Simrén; Per-Ove Stotzer; Gisela Ringström; Hasse Abrahamsson; Einar S. Björnsson
Vasoactive intestinal peptide (VIP) regulates growth in the early post-implantation embryo. Previous work has demonstrated that peptide agonists (SALLRSIPA and NAPVSIPQ) from downstream mediators that are regulated by VIP were able to prevent the alcohol-induced fetal death, growth restriction and microcephaly associated with fetal alcohol syndrome. Here we evaluated the role of VIP in this mouse model of fetal alcohol
Catherine Y Spong; Jonathan Auth; Joy Vink; Katie Goodwin; Daniel T Abebe; Joanna M Hill; Douglas E Brenneman
The intestinal bacteria of vertebrates form a close relationship with their host. External and internal conditions of the host, including its habitat, affect the intestinal bacterial community. Similarly, the intestinal bacterial community can, in turn, influence the host, particularly with respect to disease resistance. We compared the intestinal bacterial communities of grass carp that were collected from farm-ponds or a lake. We conducted denaturing gradient gel electrophoresis of amplified 16S rRNA genes, from which 66 different operational taxonomic units were identified. Using both the unweighted pair-group method with arithmetic means clustering and principal component analysis ordination, we found that the intestinal bacterial communities from the two groups of pond fish were clustered together and inset into the clusters of wild fish, except for DF-7, and there was no significant correlation between genetic diversity of grass carp and their intestinal bacterial communities (Mantel one-tailed test, R=0.157, P=0.175). Cetobacterium appeared more frequently in the intestine of grass carp collected from pond. A more thorough understanding of the role played by intestinal microbiota on fish health would be of considerable benefit to the aquaculture industry.
Ni, Jiajia; Yu, Yuhe; Zhang, Tanglin; Gao, Lei
Enteric dysbiosis plays an essential role in the pathogenesis of alcoholic liver disease (ALD). Detailed characterization of the alterations in the gut microbiome is needed for understanding their pathogenic role in ALD and developing effective therapeutic approaches using probiotic supplementation. Mice were fed liquid Lieber-DeCarli diet without or with alcohol (5% v/v) for 6 weeks. A subset of mice were administered the probiotic Lactobacillus rhamnosus GG (LGG) from 6 to 8 weeks. Indicators of intestinal permeability, hepatic steatosis, inflammation and injury were evaluated. Metagenomic analysis of the gut microbiome was performed by analyzing the fecal DNA by amplification of the V3-V5 regions of the 16S rRNA gene and large-scale parallel pyrosequencing on the 454 FLX Titanium platform. Chronic ethanol feeding caused a decline in the abundance of both Bacteriodetes and Firmicutes phyla, with a proportional increase in the gram negative Proteobacteria and gram positive Actinobacteria phyla; the bacterial genera that showed the biggest expansion were the gram negative alkaline tolerant Alcaligenes and gram positive Corynebacterium. Commensurate with the qualitative and quantitative alterations in the microbiome, ethanol caused an increase in plasma endotoxin, fecal pH, hepatic inflammation and injury. Notably, the ethanol-induced pathogenic changes in the microbiome and the liver were prevented by LGG supplementation. Overall, significant alterations in the gut microbiome over time occur in response to chronic alcohol exposure and correspond to increases in intestinal barrier dysfunction and development of ALD. Moreover, the altered bacterial communities of the gut may serve as significant therapeutic target for the prevention/treatment of chronic alcohol intake induced intestinal barrier dysfunction and liver disease. PMID:23326376
Bull-Otterson, Lara; Feng, Wenke; Kirpich, Irina; Wang, Yuhua; Qin, Xiang; Liu, Yanlong; Gobejishvili, Leila; Joshi-Barve, Swati; Ayvaz, Tulin; Petrosino, Joseph; Kong, Maiying; Barker, David; McClain, Craig; Barve, Shirish
Enteric dysbiosis plays an essential role in the pathogenesis of alcoholic liver disease (ALD). Detailed characterization of the alterations in the gut microbiome is needed for understanding their pathogenic role in ALD and developing effective therapeutic approaches using probiotic supplementation. Mice were fed liquid Lieber-DeCarli diet without or with alcohol (5% v/v) for 6 weeks. A subset of mice were administered the probiotic Lactobacillus rhamnosus GG (LGG) from 6 to 8 weeks. Indicators of intestinal permeability, hepatic steatosis, inflammation and injury were evaluated. Metagenomic analysis of the gut microbiome was performed by analyzing the fecal DNA by amplification of the V3–V5 regions of the 16S rRNA gene and large-scale parallel pyrosequencing on the 454 FLX Titanium platform. Chronic ethanol feeding caused a decline in the abundance of both Bacteriodetes and Firmicutes phyla, with a proportional increase in the gram negative Proteobacteria and gram positive Actinobacteria phyla; the bacterial genera that showed the biggest expansion were the gram negative alkaline tolerant Alcaligenes and gram positive Corynebacterium. Commensurate with the qualitative and quantitative alterations in the microbiome, ethanol caused an increase in plasma endotoxin, fecal pH, hepatic inflammation and injury. Notably, the ethanol-induced pathogenic changes in the microbiome and the liver were prevented by LGG supplementation. Overall, significant alterations in the gut microbiome over time occur in response to chronic alcohol exposure and correspond to increases in intestinal barrier dysfunction and development of ALD. Moreover, the altered bacterial communities of the gut may serve as significant therapeutic target for the prevention/treatment of chronic alcohol intake induced intestinal barrier dysfunction and liver disease.
Kirpich, Irina; Wang, Yuhua; Qin, Xiang; Liu, Yanlong; Gobejishvili, Leila; Joshi-Barve, Swati; Ayvaz, Tulin; Petrosino, Joseph; Kong, Maiying; Barker, David; McClain, Craig; Barve, Shirish
This study evaluated whether or not bovine colostrum (BC) is able to treat or prevent intestinal barrier damage, bacterial translocation, and the related systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS) in an intestinal ischemia/reperfusion (I/R)-injured rat model. Fifty Sprague-Dawley rats were used. The rats' intestinal I/R injuries were induced by clamping the superior mesenteric artery for 30 minutes. After 3 hours of reperfusion and then twice daily reclamping during the experiment, the experimental group was given BC (4 mL/kg/day) perorally, and the other groups received 0.9% saline and low fat milk (LFM) after intestinal I/R injury. Seventy-two hours later we assessed (1) intestinal damage and intestinal permeability, (2) enteric bacterial count and bacterial translocation, (3) serum albumin, protein, and hepatic enzyme levels, (4) pathologic findings of ileum and lung, (5) activity of oxygen-free radical species, and (6) pro-inflammatory cytokines (tumor necrosis factor-alpha and interleukin-1beta). Intestinal damage, intestinal permeability, and bacterial translocation to other organs were significantly reduced in rats fed with BC after I/R when compared to rats fed LFM/saline after I/R (P < .05). In the evaluation of acute lung injury, neutrophils were found only in the lungs of the saline-fed group after I/R, and the wet/dry ratio of the lung tissue was significantly reduced in the BC-fed group after I/R compared to other I/R groups. A marked difference was found between LFM/saline-fed groups and BC-fed groups regarding malondialdehyde (P < .05) and pro-inflammatory cytokines (P < .01). In conclusion, BC may have beneficial effects in treating and preventing intestinal barrier damage, bacterial translocation and the related SIRS and MODS in the intestinal I/R-injured rat model. PMID:19298194
Choi, Han Sung; Jung, Kyung Hee; Lee, Seung Chul; Yim, Sung Vin; Chung, Joo-Ho; Kim, Youn Wha; Jeon, Woo Kyu; Hong, Hoon Pyo; Ko, Young Gwan; Kim, Chul-Ho; Jang, Ki-Hyo; Kang, Soon Ah
We studied etiologic structure of bacterial intestinal infections in monkeys of Adler nursery. A total of 533 monkeys with diarrhea syndrome and monkeys dead from intestinal infections, as well as clinically healthy monkeys and animals dead from other pathologies were examined by bacteriological and molecular-genetic methods. Pathogenic enterobacteria Shigella and Salmonella and microaerophile Campylobacter were found in 5 and 19%, respectively. A high percentage (49%) of intestinal diseases of unknown etiology was revealed in monkeys. The fact that the number of detected opportunistic enterobacteria did not differ in healthy and diseased monkeys suggests that they are not involved into the etiology of intestinal disease. PMID:22485220
Ardasheliya, S N; Kalashnikova, V A; Dzhikidze, E K
Ras homolog gene family, member A (RhoA) is a small GTPase protein known to regulate multiple cellular processes. In the present study, we used both an alcohol-fed mouse model and an alcohol-treated Caco-2 intestinal epithelial cell monolayer in vitro model to investigate whether RhoA is involved in alcohol-induced intestinal barrier dysfunction as well as the underlying mechanisms. We found that chronic alcohol exposure significantly increased both intestinal RhoA mRNA and protein levels in mice and alcohol treatment also increased RhoA activity in Caco-2 cells. The alcohol-induced elevation in RhoA activity was accompanied by an increase in inducible nitric oxide synthase (iNOS) expression and prevented by N?-(1-iminoethyl)-L-lysine dihydrochloride (L-NIL) or small interfering RNA (siRNA) specific for iNOS. Furthermore, alcohol treatment with Caco-2 cells resulted in a significant decrease in the epithelial transepithelial electrical resistance (TEER) value, which was attenuated by knockdown of RhoA. Taken together, our findings suggest that iNOS-mediated activation of RhoA appears to be one of the important mechanisms contributing to the deleterious effects of alcohol on intestinal barrier function. PMID:23361851
Tong, Jing; Wang, Ying; Chang, Bing; Zhang, Dai; Liu, Pengliang; Wang, Bingyuan
The effect of acute exposure of the rabbit jejunum to ethanol on the uptake of fatty acids, fatty alcohols, and cholesterol was examined using a previously validatedin vitro technique. The effective resistance of the intestinal unstirred water layer was determined from the rate of uptake of a homologous series of fatty alcohols. The addition of ethanol to the incubation or
A. B. R. Thomson; S. F. P. Man; T. Shnitka
The water-soluble vitamin biotin is essential for normal cellular functions and its deficiency leads to a variety of clinical abnormalities. Mammals obtain biotin from exogenous sources via intestinal absorption, a process mediated by the sodium-dependent multivitamin transporter (SMVT). Chronic alcohol use in humans is associated with a significant reduction in plasma biotin levels, and animal studies have shown inhibition in intestinal biotin absorption by chronic alcohol feeding. Little, however, is known about the cellular and molecular mechanisms involved in the inhibition in intestinal biotin transport by chronic alcohol use. These mechanisms were investigated in this study by using rats and transgenic mice carrying the human full-length SLC5A6 5?-regulatory region chronically fed alcohol liquid diets; human intestinal epithelial Caco-2 cells chronically exposed to alcohol were also used as models. The results showed chronic alcohol feeding of rats to lead to a significant inhibition in carrier-mediated biotin transport events across jejunal brush border and basolateral membrane domains. This inhibition was associated with a significant reduction in level of expression of the SMVT protein, mRNA, and heterogenous nuclear RNA. Chronic alcohol feeding also inhibited carrier-mediated biotin uptake in rat colon. Studies with transgenic mice confirmed the above findings and further showed chronic alcohol feeding significantly inhibited the activity of SLC5A6 5?-regulatory region. Finally, chronic exposure of Caco-2 cells to alcohol led to a significant decrease in the activity of both promoters P1 and P2 of the human SLC5A6 gene. These studies identify for the first time the cellular and molecular parameters of the intestinal biotin absorptive processes that are affected by chronic alcohol feeding.
Subramanya, Sandeep B.; Subramanian, Veedamali S.; Kumar, Jeyan S.; Hoiness, Robert
Gut microbiota has become an integral component of the host, and received increasing attention. However, for many domestic animals, information on the microbiota is insufficient and more effort should be exerted to manage the gastrointestinal bacterial community. Understanding the factors that influence the composition of microbial community in the host alimentary canal is essential to manage or improve the microbial community composition. In the present study, 16S rRNA gene sequence-based comparisons of the bacterial communities in the grass carp (Ctenopharyngodon idellus) intestinal contents and fish culture-associated environments are performed. The results show that the fish intestinal microbiota harbors many cellulose-decomposing bacteria, including sequences related to Anoxybacillus, Leuconostoc, Clostridium, Actinomyces, and Citrobacter. The most abundant bacterial operational taxonomic units (OTUs) in the grass carp intestinal content are those related to feed digestion. In addition, the potential pathogens and probiotics are important members of the intestinal microbiota. Further analyses show that grass carp intestine holds a core microbiota composed of Proteobacteria, Firmicutes, and Actinobacteria. The comparison analyses reveal that the bacterial community in the intestinal contents is most similar to those from the culture water and sediment. However, feed also plays significant influence on the composition of gut microbiota.
Wu, Shangong; Wang, Guitang; Angert, Esther R.; Wang, Weiwei; Li, Wenxiang; Zou, Hong
Intestinal bacterial communities in aquaculture have been drawn to attention due to potential benefit to their hosts. To identify core intestinal bacteria in the black tiger shrimp (Penaeus monodon), bacterial populations of disease-free shrimp were characterized from intestines of four developmental stages (15-day-old post larvae (PL15), 1- (J1), 2- (J2), and 3-month-old (J3) juveniles) using pyrosequencing, real-time PCR and denaturing gradient gel electrophoresis (DGGE) approaches. A total of 25,121 pyrosequencing reads (reading length?=?442±24 bases) were obtained, which were categorized by barcode for PL15 (7,045 sequences), J1 (3,055 sequences), J2 (13,130 sequences) and J3 (1,890 sequences). Bacteria in the phyla Bacteroides, Firmicutes and Proteobacteria were found in intestines at all four growth stages. There were 88, 14, 27, and 20 bacterial genera associated with the intestinal tract of PL15, J1, J2 and J3, respectively. Pyrosequencing analysis revealed that Proteobacteria (class Gammaproteobacteria) was a dominant bacteria group with a relative abundance of 89% for PL15 and 99% for J1, J2 and J3. Real-time PCR assay also confirmed that Gammaproteobacteria had the highest relative abundance in intestines from all growth stages. Intestinal bacterial communities from the three juvenile stages were more similar to each other than that of the PL shrimp based on PCA analyses of pyrosequencing results and their DGGE profiles. This study provides descriptive bacterial communities associated to the black tiger shrimp intestines during these growth development stages in rearing facilities. PMID:23577162
Rungrassamee, Wanilada; Klanchui, Amornpan; Chaiyapechara, Sage; Maibunkaew, Sawarot; Tangphatsornruang, Sithichoke; Jiravanichpaisal, Pikul; Karoonuthaisiri, Nitsara
OBJECTIVE. The authors investigated the role of mucin and secretory immunoglobulin A (slgA) in a model of nutritionally induced bacterial translocation. BACKGROUND. Parenteral and certain elemental diets have been shown to impair intestinal barrier function, whereas fiber has been shown to protect against nutritionally induced bacterial translocation. However, the factors responsible for these phenomenon have not been fully determined. METHODS. Intestinal mucin levels, mucosal protein content, slgA, intestinal morphology, and permeability to horseradish peroxidase, bacterial translocation, and intestinal bacterial population levels were measured in rats 7 days after receiving total parenteral nutrition (TPN) solution (28% glucose, 4.25% amino acids; 307 kcal/kg/day) enterally (ORAL-TPN) or parenterally (IV-TPN) with or without enteral bulk fiber supplementation. Chow-fed rats served as control subjects. RESULTS. The incidence of bacterial translocation in the ORAL-TPN and IV-TPN groups was reduced significantly by the provision of fiber (p < 0.05). Mucosal protein, slgA, and insoluble mucin levels were decreased in the jejunum of the ORAL-TPN and IV-TPN groups, with mucosal protein levels being decreased to a greater extent than slgA or mucin. Although similar decreases in these parameters were observed in the fiber-fed groups, fiber appeared to improve intestinal barrier function as measured by horseradish peroxidase permeability. CONCLUSIONS. The provision of bulk-forming fiber improves intestinal barrier function as measured by peroxidase permeability and bacterial translocation, but does not restore mucosal protein content, intestinal mucin, or slgA levels to normal. Images Figure 2. Figure 3. Figure 4. Figure 5.
Spaeth, G; Gottwald, T; Specian, R D; Mainous, M R; Berg, R D; Deitch, E A
In addition to its role in absorbing nutrients, the intestinal mucosa provides an important barrier against toxins and bacteria in the bowel lumen. The present study evaluated gut barrier function following orthotopic (in continuity) intestinal grafting in rats. Graft histology, intestinal permeability, and bacterial translocation to the grafted mesenteric lymph nodes, the host's liver, and the host's spleen were assessed on the 3rd, 5th, and 7th postoperative days. The study group received no immunosuppression after allotransplantation. The two control groups included rats with isografts and rats with cyclosporine-treated allografts. On the 7th POD, the study animals had moderate transmural inflammation due to rejection, with normal histology in the isografts and CsA-treated allografts; increased intestinal permeability, measured by urinary excretion of oral 51Cr-EDTA (P less than 0.01); and increased number of bacteria in the MLN and spleen (P less than 0.05). The number of bacteria in the MLN and spleen of the study group positively correlated with the changes in intestinal permeability (P less than 0.05). Rejection of the orthotopic intestinal graft leads to increased intestinal permeability and bacterial translocation from the lumen of the graft to the host's reticuloendothelial system. Measures to improve gut barrier function and antibiotic therapy during rejection episodes may help reduce the incidence of septic complications after intestinal grafting.
Grant, D.; Hurlbut, D.; Zhong, R.; Wang, P.Z.; Chen, H.F.; Garcia, B.; Behme, R.; Stiller, C.; Duff, J. (University of Western Ontario (Canada))
The epithelium of the intestinal tract is a key barrier between the external environment and the internal body environment.\\u000a Intestinal epithelial cells are targets for luminal bacteria and viruses and must discriminate between pathogenic and nonpathogenic\\u000a commensal organisms. Pathogenic bacteria and their secreted products influence epithelial cell function and induce diarrhea\\u000a by numerous mechanisms that range from an effect on
Asma Nusrat; Shanthi V. Sitaraman; Andrew Neish
Endotoxemia is a contributing cofactor to alcoholic liver disease (ALD), and alcohol-induced increased intestinal permeability is one of the mechanisms of endotoxin absorption. Probiotic bacteria have been shown to promote intestinal epithelial integrity and protect barrier function in inflammatory bowel disease (IBD) and in ALD. Although it is highly possible that some common molecules secreted by probiotics contribute to this action in IBD, the effect of probiotic culture supernatant has not yet been studied in ALD. We examined the effects of Lactobacillus rhamnosus GG culture supernatant (LGG-s) on the acute alcohol-induced intestinal integrity and liver injury in a mouse model. Mice on standard chow diet were supplemented with supernatant from LGG culture (10(9) colony-forming unit/mouse) for 5 days, and one dose of alcohol at 6 g/kg body wt was administered via gavage. Intestinal permeability was measured by FITC-FD-4 ex vivo. Alcohol-induced liver injury was examined by measuring the activity of alanine aminotransferase (ALT) in plasma, and liver steatosis was evaluated by triglyceride content and Oil Red O staining of the liver sections. LGG-s pretreatment restored alcohol-induced reduction in ileum mRNA levels of claudin-1, intestine trefoil factor (ITF), P-glycoprotein (P-gp), and cathelin-related antimicrobial peptide (CRAMP), which play important roles on intestinal barrier integrity. As a result, LGG-s pretreatment significantly inhibited the alcohol-induced intestinal permeability, endotoxemia and subsequently liver injury. Interestingly, LGG-s pretreatment increased ileum mRNA expression of hypoxia-inducible factor (HIF)-2?, an important transcription factor of ITF, P-gp, and CRAMP. These results suggest that LGG-s ameliorates the acute alcohol-induced liver injury by promoting HIF signaling, leading to the suppression of alcohol-induced increased intestinal permeability and endotoxemia. The use of bacteria-free LGG culture supernatant provides a novel strategy for prevention of acute alcohol-induced liver injury. PMID:22538402
Wang, Yuhua; Liu, Yanlong; Sidhu, Anju; Ma, Zhenhua; McClain, Craig; Feng, Wenke
Endotoxemia is a contributing cofactor to alcoholic liver disease (ALD), and alcohol-induced increased intestinal permeability is one of the mechanisms of endotoxin absorption. Probiotic bacteria have been shown to promote intestinal epithelial integrity and protect barrier function in inflammatory bowel disease (IBD) and in ALD. Although it is highly possible that some common molecules secreted by probiotics contribute to this action in IBD, the effect of probiotic culture supernatant has not yet been studied in ALD. We examined the effects of Lactobacillus rhamnosus GG culture supernatant (LGG-s) on the acute alcohol-induced intestinal integrity and liver injury in a mouse model. Mice on standard chow diet were supplemented with supernatant from LGG culture (109 colony-forming unit/mouse) for 5 days, and one dose of alcohol at 6 g/kg body wt was administered via gavage. Intestinal permeability was measured by FITC-FD-4 ex vivo. Alcohol-induced liver injury was examined by measuring the activity of alanine aminotransferase (ALT) in plasma, and liver steatosis was evaluated by triglyceride content and Oil Red O staining of the liver sections. LGG-s pretreatment restored alcohol-induced reduction in ileum mRNA levels of claudin-1, intestine trefoil factor (ITF), P-glycoprotein (P-gp), and cathelin-related antimicrobial peptide (CRAMP), which play important roles on intestinal barrier integrity. As a result, LGG-s pretreatment significantly inhibited the alcohol-induced intestinal permeability, endotoxemia and subsequently liver injury. Interestingly, LGG-s pretreatment increased ileum mRNA expression of hypoxia-inducible factor (HIF)-2?, an important transcription factor of ITF, P-gp, and CRAMP. These results suggest that LGG-s ameliorates the acute alcohol-induced liver injury by promoting HIF signaling, leading to the suppression of alcohol-induced increased intestinal permeability and endotoxemia. The use of bacteria-free LGG culture supernatant provides a novel strategy for prevention of acute alcohol-induced liver injury.
Wang, Yuhua; Liu, Yanlong; Sidhu, Anju; Ma, Zhenhua; McClain, Craig
OBJECTIVES:Systemic endotoxemia has been implicated in various pathophysiological sequelae of chronic liver disease. One of its potential causes is increased intestinal absorption of endotoxin. We therefore examined the association of small intestinal bacterial overgrowth with systemic endotoxemia in patients with cirrhosis.METHODS:Fifty-three consecutive patients with cirrhosis (Child-Pugh group A, 23; group B, 18; group C, 12) were included. Jejunal secretions were
Tilman M. Bauer; Henning Schwacha; Bernhard Steinbrückner; Folke E. Brinkmann; Anette K. Ditzen; John J. Aponte; Klaus Pelz; Dieter Berger; Manfred Kist; Hubert E. Blum
OBJECTIVES:Irritable bowel syndrome is the most common gastrointestinal diagnosis. The symptoms of irritable bowel syndrome are similar to those of small intestinal bacterial overgrowth. The purpose of this study was to test whether overgrowth is associated with irritable bowel syndrome and whether treatment of overgrowth reduces their intestinal complaints.METHODS:Two hundred two subjects in a prospective database of subjects referred from
Mark Pimentel; Evelyn J. Chow; Henry C. Lin
Vitamin D receptor (VDR) plays an essential role in gastrointestinal inflammation. Most investigations have focused on the immune response; however, how bacteria regulate VDR and how VDR modulates the nuclear factor (NF)-?B pathway in intestinal epithelial cells remain unexplored. This study investigated the effects of VDR ablation on NF-?B activation in intestinal epithelia and the role of enteric bacteria on VDR expression. We found that VDR?/? mice exhibited a pro-inflammatory bias. After Salmonella infection, VDR?/? mice had increased bacterial burden and mortality. Serum interleukin-6 in noninfected VDR+/+ mice was undetectable, but was easily detectable in VDR?/? mice. NF-?B p65 formed a complex with VDR in noninfected wild-type mouse intestine. In contrast, deletion of VDR abolished VDR/P65 binding. P65 nuclear translocation occurred in colonic epithelial cells of untreated VDR?/? mice. VDR deletion also elevated NF-?B activity in intestinal epithelia. VDR was localized to the surface epithelia of germ-free mice, but to crypt epithelial cells in conventionalized mice. VDR expression, distribution, transcriptional activity, and target genes were regulated by Salmonella stimulation, independent of 1,25-dihydroxyvitamin D3. Our study demonstrates that commensal and pathogenic bacteria directly regulate colonic epithelial VDR expression and location in vivo. VDR negatively regulates bacterial-induced intestinal NF-?B activation and attenuates response to infection. Therefore, VDR is an important contributor to intestinal homeostasis and host protection from bacterial invasion and infection.
Wu, Shaoping; Liao, Anne P.; Xia, Yinglin; Li, Yan Chun; Li, Jian-Dong; Sartor, R. Balfour; Sun, Jun
Milk oligosaccharides influence the composition of intestinal microbiota and thereby mucosal inflammation. Some of the major milk oligosaccharides are ?2,3-sialyllactose (3SL) and ?2,6-sialyllactose, which are mainly produced by the sialyltransferases ST3GAL4 and ST6GAL1, respectively. Recently, we showed that mice fed milk deficient in 3SL were more resistant to dextran sulfate sodium-induced colitis. By contrast, the exposure to milk containing or deficient in 3SL had no impact on the development of mucosal leukocyte populations. Milk 3SL mainly affected the colonization of the intestine by clostridial cluster IV bacteria.
Weiss, G. Adrienne; Hennet, Thierry
Microorganisms in the intestinal tracts of termites play a crucial role in the nutritional physiology of termites. The bacterial diversity in the fungus-cultivating Macrotermes michaelseni was examined using both molecular and culture dependent methods. Total DNA was extracted from the gut of the termite and 16S rRNA genes were amplified using bacterial specific primers. Representatives from forty-one (41) RFLP patterns
Lucy Mwende Mackenzie; Anne Thairu Muigai; Ellie Onyango Osir; Wilber Lwande; Martin Keller; Gerardo Toledo; Hamadi Iddi Boga
Folate mediated one-carbon metabolism is of fundamental importance for various cellular processes, including DNA synthesis and methylation of biological molecules. Due to the exogenous requirement of folate in mammals, there exists a well developed epithelial folate transport system for regulation of normal folate homeostasis. The intestinal and renal folate uptake is tightly and diversely regulated and disturbances in folate homeostasis like in alcoholism have pathological consequences. The study was sought to delineate the regulatory mechanism of folate uptake in intestine and reabsorption in renal tubular cells that could evaluate insights of malabsorption during alcoholism. The folate transporters PCFT and RFC were found to be associated with lipid rafts of membrane surfaces in intestine and kidney. Importantly, the observed lower intestinal and renal folate uptake was associated with decreased levels of folate transporter viz. PCFT and RFC in lipid rafts of intestinal and renal membrane surfaces. The decreased association of folate transporters in lipid rafts was associated with decreased protein and mRNA levels. In addition, immunohistochemical studies showed that alcoholic conditions deranged that localization of PCFT and RFC. These findings could explain the possible mechanistic insights that may result in folate malabsorption during alcoholism. PMID:23267781
Wani, Nissar Ahmad; Thakur, Shilpa; Najar, Rauf Ahmad; Nada, Ritambhara; Khanduja, Krishan Lal; Kaur, Jyotdeep
Abstract Abstract Abstract Abstract AIM: To investigate the effect of fermented soy milk on human ecosystem in the intestinal tract by way of examining the population of different microorganisms isolated from fecal samples. METHODS: A crossover experimental design was applied. Twenty-eight healthy adults completed this experiment. Each subject consumed 250 mL, twice a day between meals, of either fermented soy
I-Chi Cheng; Huey-Fang Shang; Tzann-Feng Lin; Tseng-Hsing Wang; Hao-Sheng Lin; Shyh-Hsiang Lin
As it is known that food waste can be reduced by the larvae of Hermetia illucens (Black soldier fly, BSF), the scientific and commercial value of BSF larvae has increased recently. We hypothesised that the ability of catabolic degradation by BSF larvae might be due to intestinal microorganisms. Herein, we analysed the bacterial communities in the gut of BSF larvae by pyrosequencing of extracting intestinal metagenomic DNA from larvae that had been fed three different diets. The 16S rRNA sequencing results produced 9737, 9723 and 5985 PCR products from larval samples fed food waste, cooked rice and calf forage, respectively. A BLAST search using the EzTaxon program showed that the bacterial community in the gut of larvae fed three different diets was mainly composed of the four phyla with dissimilar proportions. Although the composition of the bacterial communities depended on the different nutrient sources, the identified bacterial strains in the gut of BSF larvae represented unique bacterial species that were unlike the intestinal microflora of other insects. Thus, our study analysed the structure of the bacterial communities in the gut of BSF larvae after three different feedings and assessed the application of particular bacteria for the efficient degradation of organic compounds. PMID:21267722
Jeon, Hyunbum; Park, Soyoung; Choi, Jiyoung; Jeong, Gilsang; Lee, Sang-Beom; Choi, Youngcheol; Lee, Sung-Jae
Introduction: Irritable bowel syndrome (IBS) is a chronic gastrointestinal tract disfunction characterized by abdominal pain (or discomfort) and alteration in bowel movements. The etiology of presented symptoms despite numerous studies is unclear. Small intestinal bacterial overgrowth (SIBO) is one of potential factors causing symptoms of some gastrointe- stinal functional disorders. The aim of the study was to check whether SIBO
The attaching and effacing (A\\/E) bacterial pathogens enteropathogenic Escherichia coli and enterohemor- rhagic E. coli and the related mouse pathogen Citrobacter rodentium colonize their hosts' intestines by infecting the apical surfaces of enterocytes, subverting their function, and they ultimately cause diarrhea. Surprisingly, little is known about the interactions of these organisms with goblet cells, which are specialized epithelial cells that
Kirk S. B. Bergstrom; Julian A. Guttman; Mohammad Rumi; Caixia Ma; Saied Bouzari; Mohammed A. Khan; Deanna L. Gibson; A. Wayne Vogl; Bruce A. Vallance
The redundant bacterial growth syndrome in the small intestine is associated with the increased total semination of over 10(5) CFU/ml presented by enterobacteria, bacteroids, clostridia, fusobacteria, etc. It is developed at the dysfunction of the gastrointestinal tract, insufficient bacteria inhibition at the time when they come from the large intestine (atony, stasis, bypasses) and is accompanied by the enhanced intestinal barrier permeability along with chronic diarrhea and intoxication. Intestinal absorption disorders cause B12-deficiency anemia, hypovitaminosis and protein deficiency. The redundant growth is diagnosed based on the hydrogen concentration in the expired air or bacterial inoculation of the small intestine aspirate. Tetracycline, Vancomycin, Metronidazole and aminoglycoside are used for the therapy; Amoxicillin/clavunate and cephalosporins of the second generation are also applied with success. Decontamination of the small intestine is more successful when probiotics are prescribed (both after antibiotics and independently), which suppress the opportunistic flora, protect the mucous coat, improve digestion and arrest diarrhea. Probifor or Bifidumbacterin forte in the complex with probiotics comprising lactobacteria can also have a therapeutic effect. PMID:17378388
Lykova, E A; Bondarenko, V M; Parfenov, A I; Matsulevich, T V
Recent investigations have shown that bacterial overgrowth of the small intestine is associated with a number of functional somatic disorders, including irritable bowel syndrome (IBS), fibromyalgia, and chronic fatigue syndrome. A number of controlled studies have shown that enteric-coated peppermint oil (ECPO) is of benefit in the treatment of IBS. However, despite evidence of strong antimicrobial activity, ECPO has not been specifically investigated for an effect on small intestinal bacterial overgrowth (SIBO). A case report of a patient with SIBO who showed marked subjective improvement in IBS-like symptoms and significant reductions in hydrogen production after treatment with ECPO is presented. While further investigation is necessary, the results in this case suggest one of the mechanisms by which ECPO improves IBS symptoms is antimicrobial activity in the small intestine. PMID:12410625
Logan, Alan C; Beaulne, Tracey M
The aim of this study was to determine the contribution of intestinal motility and cecal bacterial overgrowth to liquid diet-induced bacterial translocation (BT). Three different commercially available liquid diets were offered to mice for 1 week. BT to the mesenteric lymph nodes (MLN), spleen, and liver were examined as well as cecal bacterial counts and populations, small bowel length and weight, and histopathologic changes in the ileal and jejunal mucosa. In addition, the effect of the various diets on intestinal motility was measured by the transit index of a charcoal mixture introduced into the stomach. The incidence of BT to the mesenteric lymph nodes was significantly and similarly increased (p < .05) in mice fed Vivonex (30%), Ensure (30%), and Osmolite (33%) compared with chow-fed controls (0%). Compared with chow-fed controls, all three liquid diets were associated with the development of cecal bacterial overgrowth (p < .01). There were no significant changes in the transit index for the three liquid diet groups compared with the chow-fed controls. BT to the MLN was induced by all three liquid diets tested, casting some doubts as to their role in preventing BT in clinical use. BT was associated with a statistically significant increase in cecal bacterial count but was not associated with gut motility changes in this model. In fact, no significant changes in intestinal motility were noted in all groups tested. PMID:11284471
Haskel, Y; Udassin, R; Freund, H R; Zhang, J M; Hanani, M
Colonic epithelial cells are constantly exposed to high levels of bacterial DNA in the intestinal lumen and must recognize and respond appropriately to pathogens, while they maintain a tolerance to non- pathogenic commensal bacterial strains. Bacterial DNA is recognized by Toll-like receptor 9 (TLR9). The aim of this study was to investigate TLR9 expression and localization in colonic epithelial cells
Julia B. Ewaschuk; Jody L. Backer; Thomas A. Churchill; Florian Obermeier; Denis O. Krause; Karen L. Madsen
This study was conducted to relate the performance of broiler chickens fed diets containing growth-promoting antibiotics to changes in the intestinal microbiota. The technique of denaturing gradient gel electrophoresis (DGGE) of amplicons of the region V3 of 16S rDNA was used to characterize the microbiota. Two experiments were conducted, one with broilers raised in battery cages and the other with broilers raised in floor pens. Antibiotics improved the performance of the chickens raised in floor pens only. Avilamycin, bacitracin methylene disalicylate, and enramycin induced changes in the composition of the intestinal bacterial community of the birds in both experiments. The number of bacterial genotypes found in the intestinal tract of chickens was not reduced by the antibiotics supplemented in either environment. However, the changes in the composition of the intestinal bacterial community induced by antibiotics may be related to improvement in growth performance. This was indicated by the suppression of 6 amplicons and the presence of 4 amplicons exclusive to the treatment that had the best performance in the floor pen experiment. PMID:16615359
Pedroso, A A; Menten, J F M; Lambais, M R; Racanicci, A M C; Longo, F A; Sorbara, J O B
Wnt11 plays an essential role in gastrointestinal epithelial proliferation, and previous investigations have focused on development and immune responses. However, the roles of how enteric bacteria regulate Wnt11 and how Wnt11 modulates the host response to pathogenic bacteria remain unexplored. This study investigated the effects of Salmonella infection on Wnt activation in intestinal epithelial cells. We found that Wnt11 mRNA and protein expression were elevated after Salmonella colonization. Wnt11 protein secretion in epithelial cells was also elevated after bacterial infection. Furthermore, we demonstrated that pathogenic Salmonella regulated Wnt11 expression and localization in vivo. We found a decrease in Salmonella invasion in cells with Wnt11 overexpression compared with cells with normal Wnt11 level. IL-8 mRNA in Wnt11-transfected cells was low; however, it was enhanced in cells with a low level of Wnt11 expression. Functionally, Wnt11 overexpression inhibited Salmonella-induced apoptosis. AvrA is a known bacterial effector protein that stabilizes ?-catenin, the downstream regulator of Wnt signaling, and inhibits bacterially induced intestinal inflammation. We observed that Wnt11 expression, secretion, and transcriptional activity were regulated by Salmonella AvrA. Overall, Wnt11 is involved in the protection of the host intestinal cells by blocking the invasion of pathogenic bacteria, suppressing inflammation, and inhibiting apoptosis. Wnt11 is a novel and important contributor to intestinal homeostasis and host defense.
Liu, Xingyin; Wu, Shaoping; Xia, Yinglin; Li, Xi Emma; Xia, Yuxuan; Zhou, Zhongren David
Vitamin B2 (riboflavin, RF) is essential for normal human health. Mammals obtain RF from exogenous sources via intestinal absorption and prevent its urinary loss by reabsorption in the kidneys. Both of these absorptive events are carrier-mediated and involve specific RF transporters (RFVTs). Chronic alcohol consumption in humans is associated with a high prevalence of RF deficiency and suboptimal levels, but little is known about the effect of chronic alcohol exposure on physiological and molecular parameters of the intestinal and renal RF transport events. We addressed these issues using rats chronically fed an alcohol liquid diet and pair-fed controls as a model. The results showed that chronic alcohol feeding significantly inhibits carrier-mediated RF transport across the intestinal brush-border and basolateral membrane domains of the polarized enterocytes. This inhibition was associated with a parallel reduction in the expression of the rat RFVT-1 and -3 at the protein, mRNA, and heterogeneous nuclear RNA (hnRNA) levels. Chronic alcohol feeding also caused a significant inhibition in RF uptake in the colon. Similarly, a significant inhibition in carrier-mediated RF transport across the renal brush-border and basolateral membrane domains was observed, which again was associated with a significant reduction in the level of expression of RFVT-1 and -3 at the protein, mRNA, and hnRNA levels. These findings demonstrate that chronic alcohol exposure impairs both intestinal absorption and renal reabsorption processes of RF and that these effects are, at least in part, mediated via transcriptional mechanism(s) involving the slc52a1 and slc52a3 genes. PMID:23804199
Subramanian, Veedamali S; Subramanya, Sandeep B; Ghosal, Abhisek; Said, Hamid M
Alcohol-induced intestinal barrier dysfunction is a major contributor to alcoholic liver disease (ALD). Forkhead box protein O1 (FoxO1) is a member of the mammalian forkhead box O class (FoxO) subfamily that regulates a wide array of cellular processes. In the present study, we used both an alcohol-fed mouse model and an alcohol-treated Caco-2 intestinal epithelial cell monolayer in vitro model to investigate whether FoxO1 is involved in alcohol-induced intestinal barrier dysfunction. We found that chronic alcohol exposure to mice significantly increased both mRNA and protein levels of FoxO1 in all the examined intestinal segments with the most remarkable changes in the ileum. Alcohol treatment increased mRNA and protein levels of FoxO1 and promoted nuclear translocation of FoxO1 in Caco-2 cells. Furthermore, alcohol treatment with Caco-2 cells resulted in a significant decrease in the epithelial transepithelial electrical resistance (TEER) value, which was attenuated by knockdown of FoxO1 expression. In conclusion, our data suggest that activation of FoxO1 is likely to be a novel mechanism contributing to the deleterious effects of alcohol on intestinal barrier function. PMID:23347700
Wang, Ying; Tong, Jing; Zou, Dawei; Chang, Bing; Wang, Baifang; Wang, Bingyuan
We compared the effect of a variety of sugar alcohols on calcium absorption from the rat small and large intestine in vitro. An Ussing chamber technique was used to determine the net transport of Ca across the epithelium isolated from the jejunum, ileum, cecum, and colon of rats. The concentration of Ca in the serosal and mucosal Tris buffer solution was 1.25 mM and 10 mM, respectively. The Ca concentration in the serosal medium was determined after incubation for 30 min and the net Ca absorption was evaluated. The addition of 0.1-200 mM erythritol, xylitol, sorbitol, maltitol, palatinit, or lactitol to the mucosal medium affected net Ca absorption in the intestinal preparations. Differences in Ca transport were observed between portions of the intestine, but not between sugar alcohols tested. We concluded that sugar alcohols directly affect the epithelial tissue and promote Ca absorption from the small and large intestine in vitro. PMID:12064809
Mineo, Hitoshi; Hara, Hiroshi; Tomita, Fusao
Contaminated enteral nutrient solution (ENS) was used to assess the risks of intestinal colonization and invasive sepsis using normal mice. Dilute Osmolite containing 10(6) Group B Streptococci/ml given for 2 to 10 consecutive days resulted in the detection of organisms by rectal washing sampling and in the recovery of 10(3) to 10(4) organisms from the cecum, large intestine, and rectum. Only 10(1) organisms survived in the small intestine. Colonization, or the persistence of organisms for 10 days after exposure, was produced after 2 days of ingestion in 44% of animals and in 100% after exposure for 5 days. There were 39 septic deaths. During the 7-day ingestion interval 15 died and 24 died within 10 days after exposure. The risk of sepsis was highest for young mice. Ways to minimize bacterial contamination of ENS intended for administration to patients are discussed. PMID:3093708
Van Enk, R A; Furtado, D
Purpose Interstitial cystitis (IC) often coexists with irritable bowel syndrome (IBS). IBS may be explained by small-intestinal bacterial\\u000a overgrowth (SIBO), which increases immune activation and visceral hypersensitivity. This prospective pilot study tested hypotheses\\u000a that IC patients with gastrointestinal (GI) symptoms have SIBO, that nonabsorbable antibiotic use improves symptoms, and that\\u000a improvement is sustained by prokinetic therapy. Methods Consecutive IC patients
Leonard B. Weinstock; Carl G. Klutke; Henry C. Lin
The study was conducted to investigate the effects of dietary inclusion of fermented cottonseed meal (FCM) on the ileal and cecal bacterial microbiota of broiler chickens. A total of 300 newborn yellow-feathered broiler chickens were randomly divided into 2 treatments with 3 replicates each (50 birds per replicate): control and 80 g/kg of FCM group. The feeding trial lasted for 42 d. Ileal and cecal digesta samples were collected from 8 chicks per replicate at 21 and 42 d of age to determine the composition of bacterial microbiota using denaturing gradient gel electrophoresis, cloning, sequencing, and real-time quantitative PCR analysis. The results demonstrated that the microbial composition in the ileum and cecum were considerably affected by the diet. The similarity dendrogram of banding profiles showed a more rapid stabilization of intestinal bacterial microbiota in broilers fed diets supplemented with FCM, compared with that of the birds fed the control diet. No significant difference was observed in total number of bands and Shannon-Weaver index, indicating that FCM had no effects on bacterial diversity. However, enumeration of bacteria in the ileal and cecal contents by quantitative PCR showed an increased (P < 0.05) population of lactobacilli, as well as a decreased (P < 0.05) Escherichia coli number by the dietary inclusion of FCM. In summary, dietary inclusion of FCM did not affect the intestinal microbial diversity but shifted intestinal microbiota, with a more homogenous population and an increased colonization of lactobacilli. The results also support the concept that dietary FCM inclusion could promote the beneficial bacteria in the intestinal tract. PMID:23300306
Sun, H; Tang, J W; Fang, C L; Yao, X H; Wu, Y F; Wang, X; Feng, J
OBJECTIVES:Altered small bowel motility and a high prevalence of small intestinal bacterial overgrowth (SIBO) has been observed in patients with liver cirrhosis. Our aim was to explore the relationship between motility abnormalities, portal hypertension, and SIBO.METHODS:Twenty-four patients with liver cirrhosis were included. Twelve had portal hypertension (PH) and 12 had liver cirrhosis (LC) alone. Child-Pugh score was the same in
Steingerdur Anna Gunnarsdottir; Riadh Sadik; Steven Shev; Magnus Simrén; Henrik Sjövall; Per-Ove Stotzer; Hasse Abrahamsson; Rolf Olsson; Einar S. Bjornsson; Anna Gunnarsdottir
As it is known that food waste can be reduced by the larvae of Hermetia illucens (Black soldier fly, BSF), the scientific and commercial value of BSF larvae has increased recently. We hypothesised that\\u000a the ability of catabolic degradation by BSF larvae might be due to intestinal microorganisms. Herein, we analysed the bacterial\\u000a communities in the gut of BSF larvae
Hyunbum Jeon; Soyoung Park; Jiyoung Choi; Gilsang Jeong; Sang-Beom Lee; Youngcheol Choi; Sung-Jae Lee
Summary The birth process allows the progressive formation of complex intestinal microflora com- posed of myriad bacteria, leading to this recently identified host-bacterial mutualism in the human intestine. This kind of cross-talk originating from birth is opportunistically used by the young host to initiate its own immune system. Recent epidemiological data support the hypothesis that some increasing immune deviances observed
J. P. LANGHENDRIES
BACKGROUND: Serum Amyloid A (SAA) is a major acute phase protein of unknown function. SAA is mostly expressed in the liver, but also in other tissues including the intestinal epithelium. SAA reportedly has anti-bacterial effects, and because inflammatory bowel diseases (IBD) result from a breakdown in homeostatic interactions between intestinal epithelia and bacteria, we hypothesized that SAA is protective during
Erik RM Eckhardt; Jassir Witta; Jian Zhong; Razvan Arsenescu; Violeta Arsenescu; Yu Wang; Sarbani Ghoshal; Marcielle C de Beer; Frederick C de Beer; Willem JS de Villiers
Carbohydrate overload models of equine acute laminitis are used to study the development of lameness. It is hypothesized that a diet-induced shift in cecal bacterial communities contributes to the development of the pro-inflammatory state that progresses to laminar failure. It is proposed that vasoactive amines, protease activators and endotoxin, all bacterial derived bioactive metabolites, play a role in disease development. Questions regarding the oral bioavailability of many of the bacterial derived bioactive metabolites remain. This study evaluates the possibility that a carbohydrate-induced overgrowth of potentially pathogenic cecal bacteria occurs and that bacterial translocation contributes toward the development of the pro-inflammatory state. Two groups of mixed-breed horses were used, those with laminitis induced by cornstarch (n=6) or oligofructan (n=6) and non-laminitic controls (n=8). Cecal fluid and tissue homogenates of extra-intestinal sites including the laminae were used to enumerate Gram-negative and -positive bacteria. Horses that developed Obel grade2 lameness, revealed a significant overgrowth of potentially pathogenic Gram-positive and Gram-negative intestinal bacteria within the cecal fluid. Although colonization of extra-intestinal sites with potentially pathogenic bacteria was not detected, results of this study indicate that cecal/colonic lymphadenopathy and eosinophilia develop in horses progressing to lameness. It is hypothesized that the pro-inflammatory state in carbohydrate overload models of equine acute laminitis is driven by an immune response to the rapid overgrowth of Gram-positive and Gram-negative cecal bacterial communities in the gut. Further equine research is indicated to study the immunological response, involving the lymphatic system that develops in the model. PMID:22633481
Onishi, Janet C; Park, Joong-Wook; Prado, Julio; Eades, Susan C; Mirza, Mustajab H; Fugaro, Michael N; Häggblom, Max M; Reinemeyer, Craig R
Background Wnt signaling plays an essential role in gastrointestinal epithelial proliferation. Most investigations have focused on developmental and immune responses. Bacterial infection can be chronic and increases the risk of inflammatory bowel disease and colitis-associated cancer. However, we lack studies on how bacteria regulate Wnt proteins and how Wnts modulate the host responses to enteric bacteria. This study investigated the effects of Salmonella and E. coli on Wnt2, one of the Wnt family members, in intestinal epithelia cells. Methodology/Findings Using cultured epithelial cells, a Salmonella-colitis mouse model, and a gnotobiotic mouse model, we found that Wnt2 mRNA and protein expression levels were elevated after bacterial infection. Enteric bacteria regulate Wnt2 location in the intestine. Furthermore, we found that elevation of Wnt2 was a strategy for host defense by inhibiting cell apoptosis and inflammatory responses to infection. Using Wnt2 siRNA analysis, we show enhanced inflammatory cytokine IL-8 in epithelial cells. Cells over-expressed Wnt2 had less bacterial-induced IL-8 secretion. AvrA is a bacterial protein that inhibits inflammation by stabilizing beta-catenin, the down-stream target of Wnt. We found that the stabilization of Wnt2 was regulated through ubiquitination. Moreover, the bacterial protein AvrA from Salmonella and E. coli stabilized Wnt2 protein expression in vivo. In an ex-germ-free system, E. coli F18 expressing AvrA increased Wnt2 expression and changed Wnt2 distribution in intestine. Conclusion Wnt2 contributes to host protection in response to enteric bacteria. Our findings thus reveal a previously undefined role of Wnt for host-pathogen interaction and inflammation.
Liu, Xingyin; Lu, Rong; Wu, Shaoping; Zhang, Yong-guo; Xia, Yinglin; Sartor, R. Balfour; Sun, Jun
Milk oligosaccharides contribute to the development of the intestinal environment by acting as decoy receptors for pathogens and as prebiotics, which promote the colonization of commensal bacteria. Here, using ?2,3- and ?2,6-sialyltransferase-deficient mice, we investigated the role of the sialylated milk oligosaccharides sialyl(?2,3)lactose and sialyl(?2,6)lactose on mucosal immunity. The exposure of newborn mice to milk containing or deficient in sialyllactose had no impact on the development of mucosal leukocyte populations. However, when challenged by dextran sulfate sodium (DSS) in drinking water, adult mice that had been fostered on sialyl(?2,3)lactose-deficient milk were more resistant to colitis compared with mice fostered on normal milk or sialyl(?2,6)lactose-deficient milk. Analysis of intestinal microbiota showed different colonization patterns depending on the presence or absence of sialyl(?2,3)lactose in the milk. Germ-free mice reconstituted with intestinal microbiota isolated from mice fed on sialyl(?2,3)lactose-deficient milk were more resistant to DSS-induced colitis than germ-free mice reconstituted with standard intestinal microbiota. Thus, exposure to sialyllactose during infancy affects bacterial colonization of the intestine, which influences the susceptibility to DSS-induced colitis in adult mice. PMID:21098096
Fuhrer, Andrea; Sprenger, Norbert; Kurakevich, Ekaterina; Borsig, Lubor; Chassard, Christophe; Hennet, Thierry
Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent
Christopher B. Forsyth; Ashkan Farhadi; Shriram M. Jakate; Yueming Tang; Maliha Shaikh; Ali Keshavarzian
AIM: To study whether over-starvation aggravates intestinal mucosal injury and promotes bacterial and endotoxin translocation in a high-altitude hypoxic environment. METHODS: Sprague-Dawley rats were exposed to hypobaric hypoxia at a simulated altitude of 7000 m for 72 h. Lanthanum nitrate was used as a tracer to detect intestinal injury. Epithelial apoptosis was observed with terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Serum levels of diamino oxidase (DAO), malondialdehyde (MDA), glutamine (Gln), superoxide dismutase (SOD) and endotoxin were measured in intestinal mucosa. Bacterial translocation was detected in blood culture and intestinal homogenates. In addition, rats were given Gln intragastrically to observe its protective effect on intestinal injury. RESULTS: Apoptotic epithelial cells, exfoliated villi and inflammatory cells in intestine were increased with edema in the lamina propria accompanying effusion of red blood cells. Lanthanum particles were found in the intercellular space and intracellular compartment. Bacterial translocation to mesenteric lymph nodes (MLN) and spleen was evident. The serum endotoxin, DAO and MDA levels were significantly higher while the serum SOD, DAO and Gln levels were lower in intestine (P < 0.05). The bacterial translocation number was lower in the high altitude hypoxic group than in the high altitude starvation group (0.47 ± 0.83 vs 2.38 ± 1.45, P < 0.05). The bacterial translocation was found in each organ, especially in MLN and spleen but not in peripheral blood. The bacterial and endotoxin translocations were both markedly improved in rats after treatment with Gln. CONCLUSION: High-altitude hypoxia and starvation cause severe intestinal mucosal injury and increase bacterial and endotoxin translocation, which can be treated with Gln.
Zhou, Qi-Quan; Yang, Ding-Zhou; Luo, Yong-Jun; Li, Su-Zhi; Liu, Fu-Yu; Wang, Guan-Song
Intestinal epithelial cells and antigen-presenting cells orchestrate mucosal innate immunity. This study investigated the role of bacterial DNA in modulating epithelial and bone marrow-derived antigen-presenting cells (BM-APCs) and subsequent T-lymphocyte responses. Murine MODE-K epithelial cells and BM-APCs were treated with DNA from either Bifidobacterium breve or Salmonella enterica serovar Dublin directly and under coculture conditions with CD4+ T cells. Apical stimulation of MODE-K cells with S. Dublin DNA enhanced secretion of cytokines from underlying BM-APCs and induced interleukin-17 (IL-17) and gamma interferon (IFN-?) secretion from CD4+ T cells. Bacterial DNA isolated from either strain induced maturation and increased cytokine secretion from BM-APCs. Conditioned medium from S. Dublin-treated MODE-K cells elicited an increase in cytokine secretion similar to that seen for S. Dublin DNA. Treatment of conditioned medium from MODE-K cells with RNase and protease prevented the S. Dublin-induced increased cytokine secretion. Oral feeding of mice with B. breve DNA resulted in enhanced levels of colonic IL-10 and transforming growth factor ? (TGF?) compared with what was seen for mice treated with S. Dublin DNA. In contrast, feeding mice with S. Dublin DNA increased levels of colonic IL-17 and IL-12p70. T cells from S. Dublin DNA-treated mice secreted high levels of IL-12 and IFN-? compared to controls and B. breve DNA-treated mice. These results demonstrate that intestinal epithelial cells are able to modulate subsequent antigen-presenting and T-cell responses to bacterial DNA with pathogenic but not commensal bacterial DNA inducing effector CD4+ T lymphocytes.
Campeau, J. L.; Salim, S. Y.; Albert, E. J.; Hotte, N.
The first studies to explore 6-2 fluorotelomer alcohol [6-2 FTOH, F(CF2)6CH2CH2OH] aerobic biodegradation are described. Biodegradation yields and metabolite concentrations were determined in mixed bacterial culture (90d) and aerobic soil (180d). 6-2 FTOH primary degradation half-life was less than 2d in both. The overall mass balance in mixed bacterial culture (day 90) was ?60%. At day 90, the molar yield
Jinxia Liu; Ning Wang; Bogdan Szostek; Robert C. Buck; Patricia K. Panciroli; Patrick W. Folsom; Lisa M. Sulecki; Cheryl A. Bellin
AIM: To analyze small intestinal bacterial overgrowth in school-aged children and the relationship between hydrogen and methane production in breath tests. METHODS: This transversal study included 85 children residing in a slum and 43 children from a private school, all aged between 6 and 10 years, in Osasco, Brazil. For characterization of the groups, data regarding the socioeconomic status and basic housing sanitary conditions were collected. Anthropometric data was obtained in children from both groups. All children completed the hydrogen (H2) and methane (CH4) breath test in order to assess small intestinal bacterial overgrowth (SIBO). SIBO was diagnosed when there was an increase in H2 ? 20 ppm or CH4 ? 10 ppm with regard to the fasting value until 60 min after lactulose ingestion. RESULTS: Children from the slum group had worse living conditions and lower nutritional indices than children from the private school. SIBO was found in 30.9% (26/84) of the children from the slum group and in 2.4% (1/41) from the private school group (P = 0.0007). Greater hydrogen production in the small intestine was observed in children from the slum group when compared to children from the private school (P = 0.007). A higher concentration of hydrogen in the small intestine (P < 0.001) and in the colon (P < 0.001) was observed among the children from the slum group with SIBO when compared to children from the slum group without SIBO. Methane production was observed in 63.1% (53/84) of the children from the slum group and in 19.5% (8/41) of the children from the private school group (P < 0.0001). Methane production was observed in 38/58 (65.5%) of the children without SIBO and in 15/26 (57.7%) of the children with SIBO from the slum. Colonic production of hydrogen was lower in methane-producing children (P = 0.017). CONCLUSION: Children who live in inadequate environmental conditions are at risk of bacterial overgrowth and methane production. Hydrogen is a substrate for methane production in the colon.
Mello, Carolina Santos; Tahan, Soraia; Melli, Ligia Cristina FL; Rodrigues, Mirian Silva do Carmo; de Mello, Ricardo Martin Pereira; Scaletsky, Isabel Cristina Affonso; de Morais, Mauro Batista
A study was conducted in healthy elderly living independently in senior housing to assess the impact of a probiotic yoghurt supplement on small intestinal bacterial overgrowth. Twenty-three participants with positive and thirteen participants with negative hydrogen breath test were studied before and after a period of 4 weeks of probiotic yoghurt administration. Intestinal permeability, plasma endotoxin levels, phagocytic activity of leucocytes, cytokine production by monocytes and free radical response of neutrophils were determined. Intestinal permeability was similar for the two groups and was unaffected by probiotic treatment. Both plasma endotoxin levels and the basal phagocytic activity of leucocytes decreased after yoghurt intake in the two groups. Exposure of monocytes and neutrophils ex vivo led to an increased cytokine response and free radical response, respectively. The normalisation of the various cytokine responses was more apparent in the group with positive breath test. In addition, the plasma levels of lipoplysaccharide binding protein and soluble CD14, lipoplysaccharide pattern recognition receptors and surrogate markers of lipoplysaccharide permeability were diminished by the end of the study. In conclusion, probiotic administration in the elderly normalises the response to endotoxin, and modulates activation markers in blood phagocytes, and therefore may help reduce low-grade chronic inflammation. PMID:19353762
Schiffrin, Eduardo J; Parlesak, Alexandr; Bode, Christiane; Bode, J Christian; van't Hof, Martin A; Grathwohl, Dominik; Guigoz, Yves
The interaction between Lactococcus lactis NZ9000/pNZPNK and intestinal microflora was evaluated as a method to assess safety of genetically modified microorganisms (GMMs). L. lactis NZ9000/pNZPNK is one kind of GMM and able to produce the intracellular subtilisin NAT (nattokinase) under induction with nisin. The host strain L. lactis NZ9000 was a generally recognized as safe (GRAS) microorganism. Six groups of Wistar rats were orally administered with L. lactis NZ9000/pNZPNK and L. lactis NZ9000 for 6 weeks. Fecal and cecal contents were collected to determine the number of L. lactis NZ9000, L. lactis NZ9000/pNZPNK, Lactobacillus, coliform bacteria, beneficial bacteria Bifidobacterium and harmful bacteria Clostridium perfringens. The liver, spleen, kidney and blood were evaluated for the bacterial translocation. After 6 weeks consumption with GM and non-GM Lactococcus, no adverse effects were observed on the rat's body weight, hematological or serum biochemical parameters, or intestinal microflora. The bacterial translocation test showed that L. lactis NZ9000/pNZPNK did not translocate to any organ or blood. Bifidobacterium was significantly increased in feces after administration of both Lactococcus strains (L. lactis NZ9000 and L. lactis NZ9000/pNZPNK), while C. perfringens remained undetectable during the experiment. These results suggested that L. lactis NZ9000/pNZPNK could be safe in animal experiments and monitoring of the interaction between test strains and intestinal microflora might be applied as a method for other GMM safety assessments. PMID:20619909
Lee, Kai-Chien; Liu, Chin-Feng; Lin, Tzu-Hsing; Pan, Tzu-Ming
The bacterial composition along the intestinal tract of Danio rerio was investigated by cultivation-independent analysis of the 16S rRNA gene. Clone libraries were constructed for three compartments of the intestinal tract of individual fish. 566 individual clones were differentiated by amplified 16S rRNA gene restriction analysis (ARDRA), and clone representatives from each operational taxonomic unit (OTU) were sequenced. As reported in other studies, we found that Proteobacteria was the most prominent phylum among clone libraries from different fish. Data generated from this pilot study indicated some compositional differences in bacterial communities. Two dominant classes, Gammaproteobacteria and Bacilli, displayed different levels of abundance in different compartments; Gammaproteobacteria increased along the intestinal tract, while Bacilli decreased its abundance along the proximal-distal axis. Less obvious spatial patterns were observed for other classes. In general, bacterial diversity in the intestinal bulb was greater than that in the posterior intestine. Interindividual differences in bacterial diversity and composition were also noted in this study.
Lan, Chuan-Ching; Love, Donald R.
The bile acid breath test was studied to examine its sensitivity for establishing the diagnosis of bacterial overgrowth in comparison to that of the Schilling test and small-intestinal cultures in 12 patients with a stagnant (blind) loop syndrome, as well as in 38 patients who had other conditions with suspected bacterial contamination of the small intestine. The presence of bile
Sirus Farivar; Hans Fromm; Detlef Schindler; Friedrich W. Schmidt
When faced with invading pathogens that can lead to infection, patients must mount an effective and appropriate immune response. Altered immune function in patients who abuse alcohol has long been described in the medical literature. The alcohol-consuming host is particularly prone to infections in the lung, including bacterial pneumonia and tuberculosis. Over the last several decades, there has been increased interest in the immune mechanisms that underlie the increased risk of infection observed in this population. This article will review the basic immunology involved in the host response to an infection and then describe how alcohol disrupts many of these immune mechanisms. It will further provide an overview of lung infections which have been linked to alcohol abuse, and finally, it will address the evolving therapeutic approaches of the immune system that are being advanced to assist in caring for immunosuppressed hosts. PMID:16413723
Gamble, L; Mason, C M; Nelson, S
The aim of this paper is to present the influence of bacterial cellulose microfibrils and ?-radiation dose on poly(vinyl alcohol) (PVA)-bacterial cellulose (BC) composites. Two composite materials were obtained: the first one from PVA aqueous solution 4% and 5% wet bacterial cellulose and the second from the same PVA solution and 10% wet bacterial cellulose. In terms of PVA/dry BC ratios (w/w) for these films the ratios are 1/0.025 and 1/0.050. The obtained composite materials were characterized by infrared spectroscopy with Fourier transform (FT-IR) and UV-vis spectroscopy in order to evaluate the irradiation effect on their stability. The swelling behavior of the polymeric composites was also studied. The composite materials were compared with a film of pure PVA and a dry BC membrane.
Stoica-Guzun, Anicuta; Stroescu, Marta; Jipa, Iuliana; Dobre, Loredana; Zaharescu, Traian
Background Small intestinal bacterial overgrowth (SIBO) is a condition in which excessive levels of bacteria, mainly the colonic-type species are present in the small intestine. Recent data suggest that SIBO may contribute to the pathophysiology of Irritable bowel syndrome (IBS). The purpose of this study was to identify potential predictors of SIBO in patients with IBS. Methods Adults with IBS based on Rome II criteria who had predominance of bloating and flatulence underwent a glucose breath test (GBT) to determine the presence of SIBO. Breath samples were obtained at baseline and at 30, 45, 60, 75 and 90 minutes after ingestion of 50 g of glucose dissolved in 150 mL of water. Results of the glucose breath test, which measures hydrogen and methane levels in the breath, were considered positive for SIBO if 1) the hydrogen or methane peak was >20 ppm when the baseline was <10 ppm, or 2) the hydrogen or methane peak increased by 12 ppm when baseline was ?10 ppm. Results Ninety-eight patients were identified who underwent a GBT (mean age, 49 y; 78% female). Thirty-five patients (36%) had a positive GBT result suggestive of SIBO. A positive GBT result was more likely in patients >55 years of age (odds ratio [OR], 3.6; 95% confidence interval [CI], 1.4-9.0) and in females (OR, 4.0; 95% CI, 1.1-14.5). Hydrogen was detected more frequently in patients with diarrhea-predominant IBS (OR, 8; 95% CI, 1.4-45), and methane was the main gas detected in patients with constipation-predominant IBS (OR, 8; 95% CI, 1.3-44). There was no significant correlation between the presence of SIBO and the predominant bowel pattern or concurrent use of tegaserod, proton pump inhibitors, or opiate analgesics. Conclusions Small intestinal bacterial overgrowth was present in a sizeable percentage of patients with IBS with predominance of bloating and flatulence. Older age and female sex were predictors of SIBO in patients with IBS. Identification of possible predictors of SIBO in patients with IBS could aid in the development of successful treatment plans.
The intestinal myxosporean parasite Enteromyxum leei causes severe desquamative enteritis in gilthead sea bream (Sparus aurata) (Teleostei) that impairs nutrient absorption causing anorexia and cachexia. In fish, as in terrestrial vertebrates, intestinal goblet cells are responsible for the adherent mucus secretion overlying epithelial cells, which constitutes a first line of innate immune defense against offending microorganisms but serves also as substrate and nutrient source for the commensal microflora. The secreted intestinal mucus of parasitized (n = 6) and unexposed (n = 8) gilthead sea bream was isolated, concentrated, and subjected to downward gel chromatography. Carbohydrate and protein contents (via PAS and Bradford stainings), terminal glycosylation (via lectin ELISA), and Aeromonas hydrophila and Vibrio alginolyticus adhesion were analyzed for the isolated intestinal mucins. Parasitized fish, compared with unexposed fish, presented intestinal mucus mucins with a lower glycoprotein content and glycosylation degree at the anterior and middle intestine, whereas both glycoprotein content and glycosylation degree increased at the posterior intestine section, though only significantly for the total carbohydrate content. Additionally, a slight molecular size increase was detected in the mucin glycoproteins of parasitized fish. Terminal glycosylation of the mucus glycoproteins in parasitized fish pointed to an immature mucin secretion (N-acetyl-?-D-galactosamine increase, ?-L-fucose, and neuraminic-acid-?-2-6-galactose reduction). Bacterial adhesion to large-sized mucus glycoproteins (>2,000 kDa) of parasitized fish was significantly lower than in unexposed fish. PMID:23086443
Estensoro, Itziar; Jung-Schroers, Verena; Álvarez-Pellitero, Pilar; Steinhagen, Dieter; Sitjà-Bobadilla, Ariadna
Neonatal alcohol exposure produces long-term changes in the suprachiasmatic nucleus (SCN) that are presumably responsible for disturbances in the light–dark regulation of circadian behavior in adult rats, including the pattern of photoentrainment, rate of re-entrainment to shifted light–dark cycles, and phase-shifting responses to light. Because SCN neurons containing vasoactive intestinal polypeptide (VIP) receive direct photic input via the retinohypothalamic tract and thus play an important role in the circadian regulation of the SCN clock mechanism by light, the present study examined the long-term effects of neonatal alcohol exposure on VIP neuronal populations within the SCN of adult rats. Male Sprague-Dawley rat pups were exposed to alcohol (EtOH; 3.0, 4.5, or 6.0 g/kg/day) or isocaloric milk formula (gastrostomy control; GC) on postnatal days 4–9 using artificial-rearing methods. At 2–3 months of age, animals from the suckle control (SC), GC, and EtOH groups were exposed to constant darkness (DD) and SCN tissue was harvested for subsequent analysis of either VIP mRNA expression by quantitative polymerase chain reaction (PCR) and in situ hybridization or of VIP-immunoreactive (ir) neurons using stereological methods. Neonatal alcohol exposure had no impact on VIP mRNA expression but dramatically altered immunostaining of neurons containing this peptide within the SCN of adult rats. The relative abundance of VIP mRNA and anatomical distribution of neurons expressing this transcript were similar among all control- and EtOH-treated groups. However, the total number and density of VIP-ir neurons within the SCN were significantly decreased by about 35% in rats exposed to alcohol at a dose of 6.0 g/kg/day relative to that observed in both control groups. These results demonstrate that VIP neuronal populations in the SCN are vulnerable to EtOH-induced insult during brain development. The observed alterations in SCN neurons containing VIP may have an impact upon clock responses to light input and thus contribute to the long-term effects of neonatal alcohol exposure on the photic regulation of circadian behavior.
Farnell, Yuhua Z.; Allen, Gregg C.; Neuendorff, Nichole; West, James R.; Wei-Jung, A. Chen; Earnest, David J.
Active packaging materials are the subject of research because their performance exceeds that of traditional packaging. From\\u000a this class, antimicrobial materials extend the shelf-life of products and reduce the risk of contamination by pathogens. In\\u000a this paper, new composite materials with antimicrobial properties are obtained by using polyvinyl alcohol and bacterial cellulose\\u000a powder. Potassium (2E,4E)-hexa-2,4-dienoate was used as the antimicrobial
Iuliana Mihaela Jipa; Anicuta Stoica; Marta Stroescu; Loredana-Mihaela Dobre; Tanase Dobre; Sorin Jinga; Christu Tardei
The translocation of bacteria and bacterial products into the circulation contributes to alcoholic liver disease. Intestinal bacterial overgrowth is common in patients with alcoholic liver disease. The aims of our study were to investigate bacterial translocation, changes in the enteric microbiome, and its regulation by mucosal antimicrobial proteins in alcoholic liver disease. We used a mouse model of continuous intragastric feeding of alcohol or an isocaloric diet. Bacterial translocation occurred prior to changes observed in the microbiome. Quantitative changes in the intestinal microflora of these animals were assessed first by conventional culture techniques in the small and large intestine. Although we found no difference after 1 day or 1 week, intestinal bacterial overgrowth was observed in the gastrointestinal tract of mice fed alcohol for 3 weeks as compared to control liquid diet fed mice. Because less than 20% of all gastrointestinal bacteria are able to be cultured by conventional methodologies, we performed massively parallel pyrosequencing to further assess the qualitative changes in the intestinal microbiome following alcohol exposure. Sequencing of 16S rRNA genes revealed a relative abundance of Bacteroidetes and Verrucomicrobia bacteria in mice fed alcohol compared with a relative predominance of Firmicutes bacteria in control mice. With respect to the host’s transcriptome, alcohol feeding was associated with downregulation in gene and protein expression of bactericidal c-type lectins Reg3b and Reg3g in the small intestines. Treatment with prebiotics partially restored Reg3g protein levels, reduced bacterial overgrowth and lessened alcoholic steatohepatitis. In conclusion, alcohol feeding is associated with intestinal bacterial overgrowth and enteric dysbiosis. Intestinal antimicrobial molecules are dysregulated following chronic alcohol feeding contributing to changes in the enteric microbiome and to alcoholic steatohepatitis.
Yan, Arthur W.; Fouts, Derrick E.; Brandl, Johannes; Starkel, Peter; Torralba, Manolito; Schott, Eckart; Tsukamoto, Hide; Nelson, Karen E.; Brenner, David A.; Schnabl, Bernd
The study was conducted to investigate the effects of graded dietary inclusion levels of betaine on ileal and total tract nutrient digestibilities and intestinal bacterial metabolites in piglets. A total of eight barrows with an average initial body weight of 7.9 kg were randomly allocated to one of the four assay diets with two pigs per treatment in four repeated measurement periods. The assay diets included a basal diet based on wheat, barley and soybean meal alone, or supplemented with a liquid betaine product at dietary levels of 1.5, 3.0, or 6.0 g betaine per kilogram diet (as-fed). Ileal digestibilities of dry matter and neutral detergent fibre increased both quadratically and linearly, and ileal digestibility of glycine increased linearly as dietary betaine level increased (p < 0.05). Furthermore, total tract digestibility of crude protein increased quadratically (p < 0.05) and total tract digestibilities of most amino acids tended to increase quadratically (p = 0.06 to p = 0.11) with increasing dietary betaine level. Moreover, there were linear increases in the concentrations of most bacterial metabolites which were significant p < 0.05 for ileal d-lactic acid and for faecal diaminopimelic acid. The results demonstrate that dietary betaine supplementation stimulates bacterial fermentation of fibre in the small intestine and bacterial degradation of crude protein in the large intestine. PMID:20455968
Ratriyanto, A; Mosenthin, R; Jezierny, D; Eklund, M
The phylogenetic diversity of the intestinal microflora of a lower termite, Reticulitermes speratus, was examined by a strategy which does not rely on cultivation of the resident microorganisms. Small-subunit rRNA genes (16S rDNAs) were directly amplified from the mixed-population DNA of the termite gut by the PCR and were clonally isolated. Analysis of partial 16S rDNA sequences showed the existence of well-characterized genera as well as the presence of bacterial species for which no 16S rDNA sequence data are available. Of 55 clones sequenced, 45 were phylogenetically affiliated with four of the major groups of the domain Bacteria: the Proteobacteria, the spirochete group, the Bacteroides group, and the low-G+C-content gram-positive bacteria. Within the Proteobacteria, the 16S rDNA clones showed a close relationship to those of cultivated species of enteric bacteria and sulfate-reducing bacteria, while the 16S rDNA clones in the remaining three groups showed only distant relationships to those of known organisms in these groups. Of the remaining 10 clones, among which 8 clones formed a cluster, there was only very low sequence similarity to known 16S rRNA sequences. None of these clones were affiliated with any of the major groups within the domain Bacteria. The 16S rDNA gene sequence data show that the majority of the intestinal microflora of R. speratus consists of new, uncultured species previously unknown to microbiologists.
Ohkuma, M; Kudo, T
Bacterial translocation and the development of sepsis after small bowel transplantation may be promoted by immunological damage to the intestinal mucosa or by quantitative and qualitative changes in intestinal microflora. This study assessed the effects of rejection, graft-versus-host disease (GVHD) and immunosuppression on intestinal microflora and bacterial translocation after heterotopic rat small bowel transplantation. Isografts, allografts with and without CsA immunosuppression, and the semi-allogeneic parent to the F1 hybrid GVHD model were studied. Intestinal microflora in graft and host loops and bacterial translocation to host organs and the graft mesenteric lymph node were determined. Bacterial colonies were counted and individual colonies identified using API 20E nutrient and fermentation indicator techniques. Colony counts in isografts and allografts were significantly higher than in the native intestine, whereas there was a massive overgrowth in the native intestine in the GVHD group. The species profile for the host and graft loops was similar in animals that had received isografts, allografted animals receiving CsA, and animals undergoing GVHD. However, there was a large increase in Staphylococcus epidermidis in animals with rejection. Bacterial translocation was not detected in isografted animals, but was observed in all other animal groups, with S. epidermidis being the most prevalent organism. These findings demonstrate that rejection and GVHD are associated with shifts in intestinal microflora toward potentially pathogenic organisms and that bacterial translocation into recipient tissues poses a major threat for the development of sepsis. PMID:8249102
Price, B A; Cumberland, N S; Clark, C L; Pockley, A G; Lear, P A; Wood, R F
Patients with inflammatory bowel diseases (IBD) harbour intestinal bacterial communities with altered composition compared with healthy counterparts; however, it is unknown whether changes in the microbiota are associated with genetic susceptibility of individuals for developing disease or instead reflect other changes in the intestinal environment related to the disease itself. Since deficiencies in the innate immune receptors Nod1 and Nod2 are linked to IBD, we tested the hypothesis that Nod-signaling alters intestinal immune profiles and subsequently alters bacterial community structure. We used qPCR to analyze expression patterns of selected immune mediators in the ileum and cecum of Nod-deficient mice compared with their Nod-sufficient littermates and assessed the relative abundance of major bacterial groups sampled from the ileum, cecum and colon. The Nod1-deficient ileum exhibited significantly lower expression of Nod2, Muc2, ?- and ?-defensins and keratinocyte-derived chemokine (KC), suggesting a weakened epithelial barrier compared with WT littermates; however, there were no significant differences in the relative abundance of targeted bacterial groups, indicating that Nod1-associated immune differences alone do not promote dysbiosis. Furthermore, Nod2-deficient mice did not display any changes in the expression of immune markers or bacterial communities. Shifts in bacterial communities that were observed in this study correlated with housing conditions and were independent of genotype. These findings emphasize the importance of using F2 littermate controls to minimize environmental sources of variation in microbial analyses, to establish baseline conditions for host-microbe homeostasis in Nod-deficient mice and to strengthen models for testing factors contributing to microbial dysbiosis associated with IBD. PMID:23549220
Robertson, Susan J; Zhou, Jun Yu; Geddes, Kaoru; Rubino, Stephen J; Cho, Joon Ho; Girardin, Stephen E; Philpott, Dana J
A new aerobic bacterial strain, CIP 1-2052, isolated from an activated sludge sample, was able to use tert-butyl alcohol (TBA), a product of methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE) degradation, as its sole carbon and energy source. Cobalt ions stimulated TBA mineralization. The maximum growth and TBA degradation rates were 0.032 +/- 0.004 h(-1) and 35.8 +/- 8.5 mg TBA x g(-1) (cell dry mass) per h, respectively. The growth yield on TBA was 0.54 +/- 0.02 g x g(-1). Strain CIP 1-2052 exhibited a particular substrate specificity towards alcohols. It degraded tertiary alcohols, TBA and tert-amyl alcohol (TAA), but neither their primary and secondary alcohol homologues, nor ethanol. However, one-carbon compounds, namely methanol and formate, were degraded by strain CIP 1-2052, showing the methylotrophic nature of this isolate. The properties of this new strain suggest that it could be used for bioremediation of contaminated aquifers. PMID:11341321
Piveteau, P; Fayolle, F; Vandecasteele, J P; Monot, F
Mastodon (Mammut americanum) remains unearthed during excavation of ancient sediments usually consist only of skeletal material, due to postmortem decomposition of soft tissues by microorganisms. Two recent excavations of skeletal remains in anoxic sediments in Ohio and Michigan, however, have uncovered organic masses which appear to be remnants of the small and large intestines, respectively. Macrobotanical examinations of the composition of these masses revealed assemblages of plant material radiocarbon dated to approximately 11,500 years before the present and thought to be incompletely digested food remains from this extinct mammal. We attempted to cultivate and identify bacteria from the intestinal contents, bone-associated sediments, and sediments not in proximity to the remains using a variety of general and selective media. In all, 295 isolates were cultivated, and 38 individual taxa were identified by fatty acid-methyl ester (FAME) profiles and biochemical characteristics (API-20E). The taxonomic positions of selected enteric and obligately anaerobic bacteria were confirmed by 16S ribosomal DNA (rDNA) sequencing. Results indicate that the intestinal and bone-associated samples contained the greatest diversity of bacterial taxa and that members of the family Enterobacteriaceae represented 41% of all isolates and were predominant in the intestinal masses and sediments in proximity to the skeleton but were uncommon in the background sediments. Enterobacter cloacae was the most commonly identified isolate, and partial rDNA sequencing revealed that Rahnella aquatilis was the correct identity of strains suggested by FAME profiles to be Yersinia enterocolitica. No Bacteroides spp. or expected intestinal anaerobes were recovered. The only obligate anaerobes recovered were clostridia, and these were not recovered from the small intestinal masses. Microbiological evidence from this study supports other, macrobotanical data indicating the intestinal origin of these masses. Whether these organisms are direct descendants of the original intestinal microbiota, however, cannot be established.
Rhodes, A. N.; Urbance, J. W.; Youga, H.; Corlew-Newman, H.; Reddy, C. A.; Klug, M. J.; Tiedje, J. M.; Fisher, D. C.
The effect of dietary ornithine a-ketoglutarate (OKG) on intestinal mucosal integrity and bacterial translocation was studied in rats following administration of a single dose of abdominal radiation (1100 cGy). Following the radiation injury the rats were randomized to receive a nutritionally incomplete diet which contained only water and OKG or a control diet with water and the non-essential amino-acid glycine.
F. Kalfarentzos; J. Spiliotis; M. Melachrinou; C. H. Katsarou; I. Spiliopoulou; C. Panagopoulos; T. H. Alexandrides
Microbial fermentation of non-digestible carbohydrates in the pig's large intestine induces a shift of N excretion from urea in urine to bacterial protein in faeces. Experiments were carried out to measure the mineral N incorporation by the pig intestinal microflora using 5 purified carbohydrates in a gas-test: starch (S), cellulose (C), inulin (I), pectin (P) and xylan (X). Fermentation kinetics
J. Bindelle; A. Buldgen; D. Michaux; J. Wavreille; J. P. Destain; P. Leterme
Alterations in the luminal microflora and increased intestinal translocation have been reported to occur following experimental and clinical small bowel transplantation (SBT). Selective intestinal decontamination (SID) has been used to prevent luminal overgrowth and bacterial translocation. Despite the wide use of SID in clinical SBT, there are no data supporting its usefulness in this situation. Thus, the aim of this
Roberto Biffi; Gaetano Privitera; Caterina Matinato; Simonetta Pozzi; Lorenzo Marzona; Paolo De Rai; Bruno Andreoni; Giorgio Tiberio; Ermenegildo Frezza; David H. Van Thiel
Objective To evaluate the effect of interleukin-1? (IL-1?) on the mesenteric circulation, intestinal mucosal integrity, and bacterial translocation in a burn/endotoxemia chronic porcine model. Summary Background Data Major burn and sepsis are associated with a high mortality, ischemia/reperfusion injury to the intestine, and an increased rate of bacterial translocation. Pathologic alterations of IL-1 synthesis, degradation, and binding to receptors have been reported. Manipulation of IL-1-mediated effects might be of therapeutic utility. Methods Twenty-one female pigs were instrumented with an ultrasonic flow probe on the superior mesenteric artery and a catheter into the superior mesenteric vein. After 5 days, all animals were anesthetized, and 14 received 40% total body surface area third-degree burn. IL-1? was administered intravenously at 1,000 ng/kg to seven pigs immediately after burn. Eighteen hours after burn, 100 ?g/kg Escherichia coli lipopolysaccharide (LPS) was administered intravenously. Systemic and splanchnic hemodynamics were measured and blood samples were drawn for blood gas analysis. Intestinal permeability was assessed every 6 hours by measuring the lactulose/mannitol (L/M) excretion ratio. At the end of the study (42 hours), tissue samples were harvested for bacteriologic cultures. Results Mesenteric blood flow was significantly decreased after burn and endotoxin. Administration of IL-1? significantly improved mesenteric blood flow postburn and post-LPS. Mesenteric oxygen supply and consumption showed a significant reduction after burn. In contrast, animals treated with IL-1? showed an increase in postburn mesenteric oxygen supply and consumption. LPS-induced mesenteric hypoxia was also ameliorated by IL-1? treatment. Intestinal permeability, as assessed by the L/M ratio, showed a 7- and 10-fold elevation after thermal injury and LPS, respectively. In contrast, IL-1?-treated animals showed an increase of only three- and fourfold in the L/M ratio, respectively. Bacterial translocation was significantly increased in the burn/endotoxin group. IL-1? significantly reduced the rates of bacterial translocation. Conclusions IL-1? treatment attenuates mesenteric ischemia and reperfusion injury induced by thermal injury and endotoxemia by improving mesenteric blood flow and oxygenation. Subsequently, IL-1? reduces intestinal permeability and bacterial translocation after burn and sepsis.
Tadros, Tamer; Traber, Daniel L.; Heggers, John P.; Herndon, David N.
A 40-year-old man with severe alcoholic liver cirrhosis with a 2-day history of fatigue and abdominal pain was admitted. He reported eating sushi and sliced raw chicken a few days previously. His abdomen was distended, with shifting dullness. Based on the patient's history, physical examination and the results of abdominocentesis, he was diagnosed as having spontaneous bacterial peritonitis; blood and ascitic fluid cultures were positive for Campylobacter fetus. The patient was started on treatment with cefotaxime, which was switched after 1 week to ampicillin for an additional 3 weeks. The patient was successfully treated with the 4-week course of intravenous antibiotic therapy. PMID:23417384
Hadano, Yoshiro; Iwata, Hiroyoshi
Background /Aim: The symptoms of irritable bowel syndrome resemble those of small intestinal bacterial overgrowth (SIBO). The aim of this study was to determine the frequency of SIBO and lactose intolerance (LI) occurrence in patients with diarrhea-predominant irritable bowel syndrome (IBS-D) according to Rome III criteria. Patients and Methods: In this retrospective case-control study, patients over 18 years of age with altered bowel habit, bloating, and patients who had lactose Hydrogen breath test (H2BT) done were included. The “cases” were defined as patients who fulfill Rome III criteria for IBS-D, while “controls” were those having chronic nonspecific diarrhea (CNSD) who did not fulfill Rome III criteria for IBS-D. Demographic data, predominant bowel habit pattern, concurrent use of medications, etc., were noted. Results: Patients with IBS-D were 119 (51%) with a mean age of 35 ± 13 years, while those with CNSD were 115 (49%) with mean age 36 ± 15 years. Patients in both IBS-D and CNSD were comparable in gender, with male 87 (74%) and female 77 (64%). SIBO was documented by lactose H2BT in 32/234 (14%) cases. It was positive in 22/119 (19%) cases with IBS-D, while 10/115 (9%) cases had CNSD (P = 0.03). LI was positive in 43/234 (18%) cases. Of these, 25/119 (21%) cases had IBS-D and 18/115 (16%) cases had CNSD (P = 0.29). Conclusion: SIBO was seen in a significant number of our patients with IBS-D. There was no significant age or gender difference in patients with or without SIBO.
Yakoob, Javed; Abbas, Zaigham; Khan, Rustam; Hamid, Saeed; Awan, Safia; Jafri, Wasim
A previous study had established that anaerobic continuous-flow (CF) cultures of conventional mouse cecal flora were able to maintain the in vivo ecological balance among the indigenous bacterial species tested. This paper describes experiments designed to determine the mechanisms which control the population sizes of these species in such CF cultures. One strain each of Escherichia coli, Fusobacterium sp., and Eubacterium sp. were studied. Growth of these strains in filtrates of CF cultures was considerably more rapid than in the CF cultures themselves, indicating that the inhibitory activity had been lost in the process of filtration. Growth rates to match those in CF cultures could be obtained, however, by restoring the original levels of H(2)S in the culture filtrates. The inhibitory effect of H(2)S in filtrates and in dialysates of CF cultures could be abolished by adding glucose or pyruvate, but not formate or lactate. The fatty acids present in CF cultures matched those in the cecum of conventional mice in both quality and concentration. These acids could not account for the slow rates of growth of the tested strains in CF cultures, but they did cause a marked increase in the initial lag phase of E. coli growth. The results obtained are compatible with the hypothesis that the populations of most indigenous intestinal bacteria are controlled by one or a few nutritional substrates which a given strain can utilize most efficiently in the presence of H(2)S and at the prevailing conditions of pH and anaerobiosis. This hypothesis consequently implies that the populations of enterobacteria, such as the E. coli strain tested, and those of the predominant anaerobes are controlled by analogous mechanisms. PMID:6339388
Freter, R; Brickner, H; Botney, M; Cleven, D; Aranki, A
Protective effects of steroids against ischemia-reperfusion (I\\/R) injury are well known, but there is little information about the influence of temporary inflow occlusion on intestinal barrier function or bacterial translocation. The aim of this experimental study was to investigate the effects on liver, kidney, spleen, ileal mitochondrial stress enzymes, and bacterial translocation of methylprednisolone (MP) in rats undergoing temporary liver
V. Kirimlioglu; H. Kirimlioglu; S. Yilmaz; T. Piskin; S. Tekerekoglu; Y. Bayindir
The distal intestine contains bacterial cell wall polymers capable of inducing acute and chronic polyarthritis if systemically distributed. Parenteral injection of peptidoglycan-polysaccharide (PG-PS) polymers from certain bacterial species produces spontaneously relapsing erosive synovitis in susceptible rat strains, and normally subarthropathic amounts of PG-PS and lipopolysaccharide (endotoxin) can reactivate arthritis initially induced by PG-PS. These experimental results illustrate the inflammatory potential of luminal bacterial products and the importance of genetically determined host susceptibility factors in the pathogenesis of arthritis. Normally, luminal complexing by secretory IgA and an intact epithelial barrier limits uptake of luminal antigen; however, intestinal inflammation enhances mucosal uptake and systemic distribution of potentially injurious macromolecules, including PG-PS and lipopolysaccharide. Occult intestinal inflammation, which may be related to non-steroidal anti-inflammatory drugs or may be disease-associated, occurs in approximately two thirds of patients with rheumatoid arthritis, idiopathic reactive arthritis and ankylosing spondylitis. Enhanced mucosal permeability to macromolecules occurs in rheumatoid arthritis, enteric infections and idiopathic inflammatory bowel disease. Intestinal inflammation is associated with increased mucosal IgG production and circulating immune complexes. Hyperactive IgA synthesis occurs in many types of inflammatory joint disease. Polyclonal IgA is increased in rheumatoid arthritis, Sjögren's syndrome, ankylosing spondylitis, Reiter's syndrome, and reactive arthritis following Yersinia infection. Anti-Klebsiella IgA cross-reacts with HLA-B27 antigen, and antibodies to enteric bacteria are able to lyse lymphocytes from HLA-B27 patients with ankylosing spondylitis. Anti-Yersinia IgA is produced at the mucosa in increased quantities in patients who develop arthritis following Yersinia enteritis, possibly as a consequence of defective cellular immunity. Serum concentrations of IgA correlate with activity of rheumatoid arthritis and ankylosing spondylitis, and serum IgA immune complexes are associated with rheumatoid vasculitis, suggesting that IgA contributes to the pathogenesis of arthritis. We speculate that intestinal injury may also induce or perpetuate arthritis by systemic distribution of inflammatory mediators produced by intestinal immune effector cells. PMID:2670253
Sartor, R B
The challenge of the mucosal gut associated immune system is to remain unresponsive to food products and commensal microbiota, while mounting an appropriate immune response towards pathogens. This implicates the necessity of tight immune regulation within the gut associated lymphoid tissue (GALT). Imbalance between tolerance and immunity (e.g. intestinal homeostasis) contributes to the pathogenesis of intestinal diseases like inflammatory bowel
Makgeolli is a traditional Korean alcoholic beverage manufactured with a natural starter, called nuruk, and grains. Nuruk is a starchy disk or tablet formed from wheat or grist containing various fungal and bacterial strains from the surrounding environment that are allowed to incorporate naturally into the starter, each of which simultaneously participates in the makgeolli fermentation process. In the current
Mi-Ja Jung; Young-Do Nam; Seong Woon Roh; Jin-Woo Bae
CD103+ dendritic cells (DCs) carry bacteria from the small intestine and can present antigens to T cells. Yet they have not been recorded sampling luminal bacteria or presenting bacterial antigens in mesentery lymph nodes. We used 2-photon microscopy in live Cx3cr1(+/gfp) ×Cd11c-YFP mice to study these processes. At steady state, sparse CD103+ DCs occupied the epithelium. They patrolled among enterocytes while extending dendrites toward the lumen, likely using tight-junction proteins to penetrate the epithelium. Challenge with Salmonella triggered chemokine- and toll-like receptor (TLR)-dependent recruitment of additional DCs from the lamina propria (LP). The DCs efficiently phagocytosed the bacteria using intraepithelial dendrites. Noninvasive bacteria were similarly sampled. In contrast, CD103+ DCs sampled soluble luminal antigen inefficiently. In mice harboring CD103+ DCs, antigen-specific CD8 T cells were subsequently activated in MLNs. Intestinal CD103+ DCs are therefore equipped with unique mechanisms to independently complete the processes of uptake, transportation, and presentation of bacterial antigens. PMID:23395676
Farache, Julia; Koren, Idan; Milo, Idan; Gurevich, Irina; Kim, Ki-Wook; Zigmond, Ehud; Furtado, Glaucia C; Lira, Sergio A; Shakhar, Guy
The development of bacterial resistance during selective decontamination of the digestive tract (SDD) is controversial. We studied effects on bacterial resistance one year before and during a randomized, placebo-controlled trial of SDD in a surgical intensive care unit. We randomized patients within two different topical regimens (PTA, PCA) or placebo, administered four-times daily to both the oropharynx and gastrointestinal tract.
W. Lingnau; J. Berger; F. Javorsky; M. Fille; F. Allerberger; H. Benzer
AIM: To explore whether patients with a defective ileocecal valve (ICV)/cecal distension reflex have small intestinal bacterial overgrowth. METHODS: Using a colonoscope, under conscious sedation, the ICV was intubated and the colonoscope was placed within the terminal ileum (TI). A manometry catheter with 4 pressure channels, spaced 1 cm apart, was passed through the biopsy channel of the colonoscope into the TI. The colonoscope was slowly withdrawn from the TI while the manometry catheter was advanced. The catheter was placed across the ICV so that at least one pressure port was within the TI, ICV and the cecum respectively. Pressures were continuously measured during air insufflation into the cecum, under direct endoscopic visualization, in 19 volunteers. Air was insufflated to a maximum of 40 mmHg to prevent barotrauma. All subjects underwent lactulose breath testing one month after the colonoscopy. The results of the breath tests were compared with the results of the pressures within the ICV during air insufflation. RESULTS: Nineteen subjects underwent colonoscopy with measurements of the ICV pressures after intubation of the ICV with a colonoscope. Initial baseline readings showed no statistical difference in the pressures of the TI and ICV, between subjects with positive lactulose breath tests and normal lactulose breath tests. The average peak ICV pressure during air insufflation into the cecum in subjects with normal lactulose breath tests was significantly higher than cecal pressures during air insufflation (49.33 ± 7.99 mmHg vs 16.40 ± 2.14 mmHg, P = 0.0011). The average percentage difference of the area under the pressure curve of the ICV from the cecum during air insufflations in subjects with normal lactulose breath tests was significantly higher (280.72% ± 43.29% vs 100% ± 0%, P = 0.0006). The average peak ICV pressure during air insufflation into the cecum in subjects with positive lactulose breath tests was not significantly different than cecal pressures during air insufflation 21.23 ± 3.52 mmHg vs 16.10 ± 3.39 mmHg. The average percentage difference of the area under the pressure curve of the ICV from the cecum during air insufflation was not significantly different 101.08% ± 7.96% vs 100% ± 0%. The total symptom score for subjects with normal lactulose breath tests and subjects with positive lactulose breath tests was not statistically different (13.30 ± 4.09 vs 24.14 ± 6.58). The ICV peak pressures during air insufflations were significantly higher in subjects with normal lactulose breath tests than in subjects with positive lactulose breath tests (P = 0.005). The average percent difference of the area under the pressure curve in the ICV from cecum was significantly higher in subjects with normal lactulose breath tests than in subjects with positive lactulose breath tests (P = 0.0012). Individuals with positive lactulose breath tests demonstrated symptom scores which were significantly higher for the following symptoms: not able to finish normal sized meal, feeling excessively full after meals, loss of appetite and bloating. CONCLUSION: Compared to normal, subjects with a positive lactulose breath test have a defective ICV cecal distension reflex. These subjects also more commonly have higher symptom scores.
Miller, Larry S; Vegesna, Anil K; Sampath, Aiswerya Madanam; Prabhu, Shital; Kotapati, Sesha Krishna; Makipour, Kian
Background Experimental and clinical studies suggest an association between small intestinal bacterial overgrowth (SIBO) and nonalcoholic\\u000a steatohepatitis (NASH). Liver injury and fibrosis could be related to exposure to bacterial products of intestinal origin\\u000a and, most notably, endotoxin, including lipopolysaccharide (LPS).\\u000a \\u000a \\u000a \\u000a \\u000a Aim To compare the prevalence of SIBO and its relationships to LPS receptor levels and systemic cytokines in NASH patients and\\u000a healthy
Ahmed Abu Shanab; Paul Scully; Orla Crosbie; Martin Buckley; Liam O’Mahony; Fergus Shanahan; Sanaa Gazareen; Eileen Murphy; Eamonn M. M. Quigley
Ethanol is an ingredient that is intoxicating in nature. Abuse of alcohol affects nearly every bodily system. Alcohol is rapidly absorbed from the stomach, small intestine, and colon. This article provides an introduction to the health effects of alcoholism. Discussed are ethyl alcohol and methyl alcohol. PMID:23998765
To date, there is no general agreement as to which test is to be preferred for the diagnosis of small-intestinal bacterial overgrowth. The 1-g carbon-14d-xylose breath test has been proposed as a very sensitive and specific test for the diagnosis of bacterial overgrowth. However, in patients with severe gastrointestinal motor dysfunction, the lack of consistent delivery of14C-d-xylose to the region
Chi-Sen Chang; Gran-Hum Chen; Chia-Hung Kao; Shyh-Jen Wang; Shih-Nen Peng; Chih-Kuen Huang; Sek-Kwong Poon
The composition of the human intestinal flora is important for the health status of the host. The global composition and the presence of specific pathogens are relevant to the effects of the flora. Therefore, accurate quantification of all major bacterial populations of the enteric flora is needed. A TaqMan real-time PCR-based method for the quantification of 20 dominant bacterial species
Stephan J. Ott; Meike Musfeldt; Uwe Ullmann; Jochen Hampe; Stefan Schreiber
The role of Toll-like receptor 4 (TLR4)/nuclear factor-kappa-B (NF-?B) in intestinal mucosal barrier damage and bacterial translocation under hypoxic exposure is unclear. Here, we investigated their role using an acute hypobaric hypoxia model. Adult Sprague-Dawley rats were divided into control (C), hypoxia (H), hypoxia+NF-?B inhibitor pyrrolidinedithiocarbamic acid (PDTC) (100 mg. kg) (HP), hypoxia+0.5 mg/kg lipopolysaccharide (HPL), and hypoxia+PDTC+LPS (HPL) group. Except control group, other four groups were placed in a hypobaric chamber set at 7000 m. Samples were collected at 72 h after pressure reduction. Damage in ultrastructure of the intestinal tract was examined by transmission electron microscopy and bacterial translocation was detected by cultivation. Kinetic turbidimetric assay was used to measure the serum LPS. ELISA was performed to detect TNF-? and IL-6 serum concentrations. Fluorescent quantitative RT-PCR was used to measure TLR4 mRNA levels was measured using quantitative RT-PCR and protein of NF-?B p65 was measured by western blotting. Different degrees of intestinal mucosa damage were observed in groups H and HL. The damage was significantly alleviated after blockage of the TLR4/NF-?B signaling pathway. PDTC- treatment also reversed hyoxia- and LPS-induced bacterial translocation rate and increased serum levels of LPS, TNF-?, and IL-6. TLR4 mRNA levels and NF-?B p65 expression were consistent with the serum factor results. This study suggested that TLR4 and NF-?B expression increased in rat intestinal tissues after acute hypoxia exposure. PDTC-treatment reversed TLR4 and NF-?B upregulation and alleviated damage to the intestinal tract and bacterial translocation. Thus, the TLR4/NF-?B signaling pathway may be critical to the mechanism underlying hypoxia-induced damage to intestinal barrier function and bacterial translocation.
Luo, Han; Guo, Ping; Zhou, Qiquan
There is an increasing demand for cultivated fish in all over the world. Unfortunately all of these fish are sold in whole states with viscera in the fish markets in Iran. The flora of water influences intestinal flora of the live fish. Fish captured in lakes, rivers and fish farms often carry a wide range of pathogenic microorganisms in their
Afshin Akhondzadeh Basti; Taghi Zahrae Salehi; Saied Bokaie
Objective: We investigated whether oral glutamine prevents bacterial translocation.Methods: Male Wistar rats were fed with isocaloric and isoproteic standard rat chow and randomly assigned to receive glutamine (GLN) or glycine administered through an orogastric tube at 1.5 g · kg?1 · d?1 for 7 d. On day 8 of the study, the animals were anesthetized and intestinal obstruction was produced
Paolo R. O Salvalaggio; Clementino Zeni Neto; André R. D Tolazzi; Emerson L Gasparetto; Júlio C. U Coelho; Antonio C. L Campos
BACKGROUND: Campylobacter jejuni is a major cause of inflammatory diarrhoea in humans and is considered a commensal of the gastroenteric tract of the avian host. However, little is known about the interaction between C. jejuni and the avian host including the cytokine responses and the expression of the bacterial genes. We have investigated the invasiveness of primary chicken embryo intestinal
Yi-Ping Li; Hanne Ingmer; Mogens Madsen; Dang D Bang
Anti-Beauveria bassiana activity of aqueous fecal extracts from conventional German cockroaches [Blattella germanica (L.)] was detected, but was not detected in samples from germ-free German cockroaches. Subsequently, bacterial strain BGI-14 was isolated from the gut of conventional German cockroaches and was identified as Pseudomonas reactans based on 16S rDNA sequence. The strain BGI-14 not only inhibited the germination of conidia, but also inhibited the growth of B. bassiana hyphae. Further studies demonstrated that B. bassiana infections in German cockroaches orally treated with the extracts of BGI-14 fermentation were significantly weakened. Compared with the control group, the cumulative mortality rate of treatment group was reduced by 10.3% at 20 d postinoculation. These studies imply that intestinal flora with anti-B. bassiana activity might contribute to resistance of infection by entomopathogenic fungi. PMID:23726054
Zhang, Fan; Huang, Yan Hong; Liu, Shu Zhen; Zhang, Lei; Li, Bo Tai; Zhao, Xiao Xu; Fu, Ying; Liu, Jian Jun; Zhang, Xue Xia
Intestinal microbes are believed to be involved in the pathogenesis of inflammatory bowel disease. Microbes and their products are generally well tolerated by intestinal epithelial cells in the intestinal tract of healthy individuals. It is of significance to understand what breaks down the established tolerance leading to intestinal barrier dysfunction and intestinal inflammation. T84 monolayer transported peptidoglycan (PGN) was determined
Linda Wu; Bai-Sui Feng; Shao-Heng He; Peng-Yuan Zheng; Kenneth Croitoru; Ping-Chang Yang
Acute secondary disease was induced in (C57BL X CBA)F1 mice by transplanting CBA bone marrow and spleen cells following lethal whole-body irradiation. The lesions of graft-versus-host (GvH) disease were scored quantitatively by counting of degenerated crypts in subcutaneous fetal gut implants that were free of bacteria. In conventional F1 mice the damage in F1 fetal gut was twice as great as in F1 fetal gut implants carried by decontaminated chimeras. CBA fetal gut implants developed substantial damage when present in conventional chimeras, but not when present in decontaminated chimeras. These results could be explained by assuming the presence of cross-reacting antigens on intestinal bacteria and in the gut epithelial tissue. They also explained the profound protection against delayed GvH mortality provided by removal of the intestinal microflora. PMID:14265
van Bekkum, D W; Knaan, S
The interaction between Lactococcus lactis NZ9000\\/pNZPNK and intestinal microflora was evaluated as a method to assess safety of genetically modified microorganisms (GMMs). L. lactis NZ9000\\/pNZPNK is one kind of GMM and able to produce the intracellular subtilisin NAT (nattokinase) under induction with nisin. The host strain L. lactis NZ9000 was a generally recognized as safe (GRAS) microorganism. Six groups of
Kai-Chien Lee; Chin-Feng Liu; Tzu-Hsing Lin; Tzu-Ming Pan
The peritrophic matrix (PM) forms a layer composed of chitin and glycoproteins that lines the insect intestinal lumen. This physical barrier plays a role analogous to that of mucous secretions of the vertebrate digestive tract and is thought to protect the midgut epithelium from abrasive food particles and microbes. Almost nothing is known about PM functions in Drosophila, and its function as an immune barrier has never been addressed by a genetic approach. Here we show that the Drosocrystallin (Dcy) protein, a putative component of the eye lens of Drosophila, contributes to adult PM formation. A loss-of-function mutation in the dcy gene results in a reduction of PM width and an increase of its permeability. Upon bacterial ingestion a higher level of expression of antibacterial peptides was observed in dcy mutants, pointing to an influence of this matrix on bacteria sensing by the Imd immune pathway. Moreover, dcy-deficient flies show an increased susceptibility to oral infections with the entomopathogenic bacteria Pseudomonas entomophila and Serratia marcescens. Dcy mutant flies also succumb faster than wild type upon ingestion of a P. entomophila toxic extract. We show that this lethality is due in part to an increased deleterious action of Monalysin, a pore-forming toxin produced by P. entomophila. Collectively, our analysis of the dcy immune phenotype indicates that the PM plays an important role in Drosophila host defense against enteric pathogens, preventing the damaging action of pore-forming toxins on intestinal cells.
Kuraishi, Takayuki; Binggeli, Olivier; Opota, Onya; Buchon, Nicolas; Lemaitre, Bruno
The peritrophic matrix (PM) forms a layer composed of chitin and glycoproteins that lines the insect intestinal lumen. This physical barrier plays a role analogous to that of mucous secretions of the vertebrate digestive tract and is thought to protect the midgut epithelium from abrasive food particles and microbes. Almost nothing is known about PM functions in Drosophila, and its function as an immune barrier has never been addressed by a genetic approach. Here we show that the Drosocrystallin (Dcy) protein, a putative component of the eye lens of Drosophila, contributes to adult PM formation. A loss-of-function mutation in the dcy gene results in a reduction of PM width and an increase of its permeability. Upon bacterial ingestion a higher level of expression of antibacterial peptides was observed in dcy mutants, pointing to an influence of this matrix on bacteria sensing by the Imd immune pathway. Moreover, dcy-deficient flies show an increased susceptibility to oral infections with the entomopathogenic bacteria Pseudomonas entomophila and Serratia marcescens. Dcy mutant flies also succumb faster than wild type upon ingestion of a P. entomophila toxic extract. We show that this lethality is due in part to an increased deleterious action of Monalysin, a pore-forming toxin produced by P. entomophila. Collectively, our analysis of the dcy immune phenotype indicates that the PM plays an important role in Drosophila host defense against enteric pathogens, preventing the damaging action of pore-forming toxins on intestinal cells. PMID:21896728
Kuraishi, Takayuki; Binggeli, Olivier; Opota, Onya; Buchon, Nicolas; Lemaitre, Bruno
Suckling and adult mice were infected intragastrically with different doses of viable Listeria monocytogenes. The 50% lethal dose for the intragastric infection was 10(3.7) CFU for suckling mice, while adult mice were highly resistant and the 50% lethal dose was more than 10(9.3) CFU. When adult mice were infected intragastrically with 5 x 10(8) CFU of L. monocytogenes, no mice died. However, 35% of adult mice died when they were treated with cyclosporin A 1 day before infection. Although mice did not die when treated with an L. monocytogenes-resistant broad-spectrum cephalosporin, sodium cefbuperazone, before and during infection, the number of L. monocytogenes bacteria increased in the feces. The sodium cefbuperazone treatment of mice resulted in superinfection, i.e., a marked decrease of Escherichia coli and an increase of Enterococcus spp. in the intestines. Furthermore, host resistance against the intragastric infection markedly decreased when the mice were treated with both drugs. The growth of L. monocytogenes was augmented in the spleens, mesenteric lymph nodes, Peyer's patches, and feces, and the mortality of the mice was 65%. These results suggest that both cellular immunity and the intestinal bacterial flora are required for host resistance against oral L. monocytogenes infection.
Okamoto, M; Nakane, A; Minagawa, T
The first studies to explore 6-2 fluorotelomer alcohol [6-2 FTOH, F(CF(2))(6)CH(2)CH(2)OH] aerobic biodegradation are described. Biodegradation yields and metabolite concentrations were determined in mixed bacterial culture (90d) and aerobic soil (180d). 6-2 FTOH primary degradation half-life was less than 2d in both. The overall mass balance in mixed bacterial culture (day 90) was approximately 60%. At day 90, the molar yield was 6% for 6-2 FTA [F(CF(2))(6)CH(2)COOH], 23% for 6-2 FTUA [F(CF(2))(5)CFCHCOOH], 16% for 5-2 sFTOH [F(CF(2))(5)CHOHCH(3)], 6% for 5-3 acid [F(CF(2))(5)CH(2)CH(2)COOH], and 5% for PFHxA [F(CF(2))(5)COOH]. The overall mass balance in aerobic soil was approximately 67% (day 180). At day 180, the major terminal metabolites were PFPeA, [F(CF(2))(4)COOH, 30%], PFHxA (8%), PFBA [F(CF(2))(3)COOH, 2%], and 5-3 acid (15%). A new metabolite 4-3 acid [F(CF(2))(4)CH(2)CH(2)COOH] accounted for 1%, 6-2 FTOH for 3%, and 5-2 sFTOH for 7%. Based on 8-2 FTOH aerobic biodegradation pathways, PFHxA was expected in greatest yield from 6-2 FTOH degradation. However, PFPeA was observed in greatest yield in soil, suggesting a preference for alternate degradation pathways. Selected metabolites were also studied in aerobic soil. 5-3 Acid degraded to only 4-3 acid with a molar yield of 2.3%. 5-2 sFTOH degraded to PFPeA and PFHxA, and 5-2 FT Ketone [F(CF(2))(5)COCH(3)] degraded to 5-2 sFTOH, suggesting that 5-2 sFTOH is the direct precursor to PFPeA and PFHxA. Another new metabolite, 5-3 ketone aldehyde [F(CF(2))(5)COCH(2)CHO] was also identified in mixed bacterial culture. The formation of PFBA, PFPeA, and 4-3 acid indicates that multiple -CF(2)- groups in 6-2 FTOH were removed during microbial biodegradation. PMID:19931114
Liu, Jinxia; Wang, Ning; Szostek, Bogdan; Buck, Robert C; Panciroli, Patricia K; Folsom, Patrick W; Sulecki, Lisa M; Bellin, Cheryl A
Composite materials containing in different ratios poly(vinyl alcohol) (PVA), bacterial cellulose (BC) and glycerol (G) as plasticizer were obtained and exposed to different ? radiation doses using an irradiator GAMMATOR provided with 137Cs source. These films successively received up to 50 kGy absorbed doses at a dose rate of 0.4 kGy/h at room temperature. In order to study the chemical and structural changes during ? irradiation, Fourier-transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and UV-Vis spectroscopy were used. Water vapour permeability (WVP), Hunter colour parameters and hardness were also measured for the irradiated samples. Investigation revealed that WVP was not significantly affected by the irradiation. Colour measurements indicated a slight decrease of pure PVA films transparency and it made clear that all samples became more reddish and yellowish after irradiation. The samples hardness was not affected by the irradiation doses used. However, the results showed no drastic structural or chemical changes of the irradiated samples, which prove, in consequence, a good durability. These composite materials could be used as packaging materials for ? irradiated products.
Jipa, Iuliana Mihaela; Stroescu, Marta; Stoica-Guzun, Anicuta; Dobre, Tanase; Jinga, Sorin; Zaharescu, Traian
The preparation of enantiopure tertiary alcohols is of great contemporary interest due to the application of these versatile\\u000a building blocks in organic synthesis and as precursors towards high value pharmaceutical compounds. Herein, we describe two\\u000a approaches taken towards the discovery of novel biocatalysts for the synthesis of these valuable compounds. The first approach\\u000a was initiated with screening of 47 bacterial
Susanne Herter; Giang-Son Nguyen; Mark L. Thompson; Fabian Steffen-Munsberg; Frieder Schauer; Uwe T. Bornscheuer; Robert Kourist
In this study, the characterization of the bacterial community present during the fermentation of pulque, a traditional Mexican alcoholic beverage from maguey (Agave), was determined for the first time by a polyphasic approach in which both culture and non-culture dependent methods were utilized. The work included the isolation of lactic acid bacteria (LAB), aerobic mesophiles, and 16S rDNA clone libraries
Adelfo Escalante; Martha Giles-Gómez; Georgina Hernández; María Soledad Córdova-Aguilar; Agustín López-Munguía; Guillermo Gosset; Francisco Bolívar
Hydrolyzable tannins, including ellagitannins, occur in foods such as berries and nuts. Various biological activities, including antioxidant, antiviral, and antitumor activities, have been noted and reported for ellagitannins, but the absorption and metabolism of purified ellagitannins are poorly understood. We describe herein the characterization of urinary and intestinal microbial metabolites in rats after the ingestion of ellagitannins. Urine samples were collected after oral administration of ellagitannins such as geraniin ( 1), corilagin ( 2), and their related polyphenols. The suspension of rat intestinal microflora was anaerobically incubated with ellagitannins. Each sample was separated by column chromatography and/or preparative HPLC to give seven metabolites, M1- M7. The structures of these metabolites were determined on the basis of spectroscopic data and chemical evidence. These compounds, except for M1, were characterized as ellagitannin metabolites for the first time. Furthermore, among four major metabolites ( M1- M4) in urine, M2 showed an antioxidant activity comparable to intact geraniin and related polyphenols. PMID:18163562
Ito, Hideyuki; Iguchi, Ayumu; Hatano, Tsutomu
The diversity of bacterial floras in the ilea and ceca of chickens that were fed a vegetarian corn-soy broiler diet devoid of feed additives was examined by analysis of 1,230 partial 16S rRNA gene sequences. Nearly 70% of sequences from the ileum were related to those of Lactobacillus, with the majority of the rest being related to Clostridiaceae (11%), Streptococcus
Jiangrang Lu; Umelaalim Idris; Barry Harmon; Charles Hofacre; John J. Maurer; Margie D. Lee
The diversity of bacterial floras in the ilea and ceca of chickens that were fed a vegetarian corn-soy broiler diet devoid of feed additives was examined by analysis of 1,230 partial 16S rRNA gene sequences. Nearly 70% of sequences from the ileum were related to those of Lactobacillus, with the majority of the rest being related to Clostridiaceae (11%), Streptococcus (6.5%), and Enterococcus (6.5%). In contrast, Clostridiaceae-related sequences (65%) were the most abundant group detected in the cecum, with the other most abundant sequences being related to Fusobacterium (14%), Lactobacillus (8%), and Bacteroides (5%). Statistical analysis comparing the compositions of the different 16S rRNA libraries revealed that population succession occurred during some sampling periods. The significant differences among cecal libraries at 3 and 7 days of age, at 14 to 28 days of age, and at 49 days of age indicated that successions occurred from a transient community to one of increasing complexity as the birds aged. Similarly, the ileum had a stable bacterial community structure for birds at 7 to 21 days of age and between 21 to 28 days of age, but there was a very unique community structure at 3 and 49 days of age. It was also revealed that the composition of the ileal and cecal libraries did not significantly differ when the birds were 3 days old, and in fact during the first 14 days of age, the cecal microflora was a subset of the ileal microflora. After this time, the ileum and cecum had significantly different library compositions, suggesting that each region developed its own unique bacterial community as the bird matured.
Lu, Jiangrang; Idris, Umelaalim; Harmon, Barry; Hofacre, Charles; Maurer, John J.; Lee, Margie D.
The preparation of enantiopure tertiary alcohols is of great contemporary interest due to the application of these versatile building blocks in organic synthesis and as precursors towards high value pharmaceutical compounds. Herein, we describe two approaches taken towards the discovery of novel biocatalysts for the synthesis of these valuable compounds. The first approach was initiated with screening of 47 bacterial strains for hydrolytic activity towards the simple tertiary alcohol ester tert-butyl acetate. In conjunction, a second method focussed on the isolation of strains competent for growth on tert-butyl acetate as the sole source of carbon and energy. From functional screening, 10 Gram-positive Actinomycetes showed hydrolytic activity, whilst enrichment selection resulted in the identification of 14 active strains, of which five belong to the Gram-negative cell-wall type. Bacterial strains obtained from both approaches were viable for enantioselective hydrolysis of pyridine substituted tertiary alcohol esters in addition to bulky aliphatic and keto-derived substrates from the same class. Activity towards each of the test substrates was uncovered, with promising enantioselectivities of up to E = 71 in the hydrolysis of a para-substituted pyridine tertiary alcohol ester using a strain of Rhodococcus ruber. Interestingly strains of Microbacterium and Alcaligenes sp. gave opposite enantiopreference in the hydrolysis of a meta-substituted pyridine tertiary alcohol ester with E values of 17 and 54. These approaches show that via both possibilities, screening established strain collections and performing enrichment selection, it is possible to identify novel species which show activity towards sterically challenging substrates. PMID:21318363
Herter, Susanne; Nguyen, Giang-Son; Thompson, Mark L; Steffen-Munsberg, Fabian; Schauer, Frieder; Bornscheuer, Uwe T; Kourist, Robert
Immunofluorescent studies of intestinal tissues from young preruminant calves demonstrate the presence of two main populations of immunocytes synthesizing IgA and IgM. These cells had infiltrated the lamina propria of the intestine as early as 4 days of age. There was little evidence of any significant involvement of IgG1 in intestinal immune synthesis of calves at this age although activity was demonstrable in the ileum and colon of one calf. In general there were more IgG2-synthesizing cells than IgG1, but these were few compared with the main populations of IgA and IgM cells. Local antigenic stimulus to the intestinal mucosa of young fistulated calves using extracts of heat-killed Gram-negative bacteria produced antibody in the secretions over a period of approximately 3 weeks. A second administration of a similar antigenic dose produced a similar response indicating the requirement for continuous stimuli to maintain a measurable level of antibody secretion. Gel filtration and antiglobulin assays indicated that the antibacterial activity was predominantly associated with IgA and that IgM also played a significant role. Oral administration of bacterial antigens to colostrum-fed calves from 5 to 8 days of age produced a faecal antibody response, indicating that intestinal secretion could be successfully interrelated with the declining passive antibody to maintain an almost continuous level of intestinal antibody in early life.
Allen, W D; Porter, P
Rodent surgeries in biomedical research facilities are often performed in series. This practice presents many challenges to maintaining aseptic technique between animals. Here, we examined using soaking in 70% isopropyl alcohol for aerobic bacterial decontamination of surgical instruments and gloves used in a series of as many as 10 mouse laparotomy surgeries. These surgeries were performed on mice that were euthanized immediately prior to the procedure. Instruments and gloves were cultured before and after each procedure to determine the presence of aerobic bacterial contamination. To assess the efficacy of the decontamination protocol, culture results were grouped by procedure and then paired (before soak and after soak) for analysis using McNemar test at an ? level of 0.05. In addition, by using the Fisher exact test, this modified aseptic method was compared with strict aseptic technique, for which autoclaved instruments and sterile surgical gloves were used for each procedure. In this study, we observed that the modified aseptic technique using 70% isopropyl alcohol soaks prevented aerobic bacterial contamination of instruments and gloves for as many as 5 mice.
Keen, Jessica N; Austin, MaryKay; Huang, Li-Shan; Messing, Susan; Wyatt, Jeffrey D
The invention relates to the use of ethylenediamine tetraacetic acid (EDTA) and its derivatives, i.e. its salts and complexes for prevention and treatment of bacterial intestinal diseases of pigs and for increasing the effects of antibiotics exerted in such diseases. The invention also relates to compositions for animal husbandry, i.e. to veterinary compositions and to feeds and drinks which can be consumed by pigs, comprising EDTA or its derivatives.
Intestinal ischemia\\/reperfusion (I\\/R) causes mucosal barrier damage and bacterial translocation (BT), leading to septic complications. Previous in vitro studies showed that activation of sodium\\/glucose transporter 1 (SGLT1) prevented the epithelial apoptosis and permeability rise induced by microbial products. Our aim was to investigate whether luminal glucose uptake by SGLT1 protects against ischemia-induced epithelial cell death and barrier dysfunction, and to
Ching-Ying Huang; Jong-Kai Hsiao; Yen-Zhen Lu; Tsung-Chun Lee; Linda C-H Yu
Bacterial intestinal overgrowth syndrome (SIBO) treatment is based on antibiotics. Probiotics have been shown to give similar results, whilst no study is available about prebiotics. This study evaluated the addition of probiotics or prebiotics to antibiotics on SIBO symptoms in a 6-month follow-up. We enrolled 40 patients (14 males and 26 females) reporting abdominal compliant without gastrointestinal diseases/alarm symptoms. SIBO was diagnosed by the agreement of lactulose and glucose breath tests. Patients were randomly divided into two groups homogeneous for sex and age: group 1 received Rifaximin 400 mg/day for 7 days/month followed by Lactobacillus casei for 7 days more and group 2 antibiotic followed by short chain fructo-oligosaccharides. All patients recorded a questionnaire for subjective symptom evaluation according to Rome III criteria and Bristol scale for stool characters before the study and after 6 months. Statistics: Student's t and Fisher's exact tests. In group 1, a significant improvement was obtained in 5 out of 6 symptoms, whilst in group 2 in 4 out of 6 symptoms (nausea and number of bowel movements failed to improve). Despite we observed a trend of probiotics to be more effective than prebiotics, the difference in the percentage of improved symptoms was not significant (83,3% vs 66.6%; p= 0.57). Our preliminary data show a good outcome with sequential antibioticprobiotic/ prebiotic administration in patients with SIBO. PMID:23244247
Rosania, Rosa; Giorgio, Floriana; Principi, Mariabeatrice; Amoruso, Annacinzia; Monno, Rosa; Di Leo, Alfredo; Ierardi, Enzo
There are important measurements of alcoholism that are poorly understood by physicians. Professional attitudes toward alcoholic patients are often counterproductive. Americans spend about $30 billion on alcohol a year and most adults drink alcohol. Even though traditional criteria allow for recognition of the disease, diagnosis is often made late in the natural course, when intervention fails. Alcoholism is a major health problem and accounts for 10 percent of total health care costs. Still, this country's 10 million adult alcoholics come from a pool of heavy drinkers with well defined demographic characteristics. These social, cultural and familial traits, along with subtle signs of addiction, allow for earlier diagnosis. Although these factors alone do not establish a diagnosis of alcoholism, they should alert a physician that significant disease may be imminent. Focus must be directed to these aspects of alcoholism if containment of the problem is expected.
Girard, Donald E.; Carlton, Bruce E.
The bacterial storage polymer poly-beta-hydroxybutyrate (PHB) has the potential to be used as an alternative anti-infective strategy for aquaculture rearing. In this research, the effects of (partially) replacing the feed of European sea bass juveniles with PHB were investigated. During a 6-week trial period, the PHB showed the ability to act as an energy source for the fish. This indicated that PHB was degraded and used during gastrointestinal passage. The gut pH decreased from 7.7 to 7.2 suggesting that the presence of PHB in the gut led to the increased production of (short-chain fatty) acids. The diets supplemented with 2% and 5% PHB (w/w) induced a gain of the initial fish weight with a factor 2.4 and 2.7, respectively, relative to a factor 2.2 in the normal feed treatment. Simultaneously, these treatments showed the highest bacterial range-weighted richness in the fish intestine. Based on molecular analysis, higher dietary PHB levels induced larger changes in the bacterial community composition. From our results, it seems that PHB can have a beneficial effect on fish growth performance and that the intestinal bacterial community structure may be closely related to this phenomenon. PMID:20094715
De Schryver, Peter; Sinha, Amit Kumar; Kunwar, Prabesh Singh; Baruah, Kartik; Verstraete, Willy; Boon, Nico; De Boeck, Gudrun; Bossier, Peter
Background Chronic alcohol abuse causes oxidative stress, impairs alveolar macrophage immune function, and increases the risk of pneumonia and acute lung injury. Recently we determined that chronic alcohol ingestion in rats decreases zinc levels and macrophage function in the alveolar space; provocative findings in that zinc is essential for normal immune and antioxidant defenses. Alveolar macrophage immune function depends on stimulation by GM-CSF, which signals via the transcription factor PU.1. In parallel, the antioxidant response element signals via the transcription factor Nrf2. However, the role of zinc bioavailability on these signaling pathways within the alveolar space is unknown. Methods To determine the efficacy of dietary zinc supplementation on lung bacterial clearance and oxidative stress, we tested three different groups of rats: control-fed, alcohol-fed, and alcohol-fed with zinc supplementation. Rats were then inoculated with intratracheal Klebsiella pneumoniae and lung bacterial clearance was determined 24 hrs later. Isolated alveolar macrophages were isolated from uninfected animals and evaluated for oxidative stress and signaling through PU.1 and Nrf2. Results Alcohol-fed rats had a 5-fold decrease in lung bacterial clearance compared to control-fed rats. Dietary zinc supplementation of alcohol-fed rats normalized bacterial clearance and mitigated oxidative stress in the alveolar space, as reflected by the relative balance of the thiol redox pair cysteine and cystine, and increased nuclear binding of both PU.1 and Nrf2 in alveolar macrophages from alcohol-fed rats. Conclusions Dietary zinc supplementation prevents alcohol-induced alveolar macrophage immune dysfunction and oxidative stress in a relevant experimental model, suggesting that such a strategy could decrease the risk of pneumonia and lung injury in individuals with alcohol use disorders.
Mehta, Ashish J.; Joshi, Pratibha C.; Fan, Xian; Brown, Lou Ann S.; Ritzenthaler, Jeffrey D.; Roman, Jesse; Guidot, David M.
... cause diarrhea. Over time, the condition can cause bacterial infections, malnutrition, weight loss, and muscle problems in ... may include medications, such as antibiotics to treat bacterial infections, pain medication, and medication to treat intestinal ...
Introduction Small intestinal bacterial overgrowth (SIBO) occurs in varying frequency in irritable bowel syndrome (IBS). We studied the frequency of SIBO in IBS and chronic non-specific diarrhea (CNSD). Methods 129 patients with IBS (Manning's criteria), 73 with CNSD (? 4 weeks diarrhea with two of these tests normal [urine D-xylose, fecal fat and duodenal biopsy]) and 51 healthy controls (HC) were evaluated for SIBO using glucose hydrogen breath test (GHBT). Diarrhea-predominant IBS (D-IBS) was grouped into CNSD. Rise in breath hydrogen 12 ppm above basal following 100 g glucose was diagnostic of SIBO. Results Of 129 patients with IBS, 7 were constipation (C-IBS), and 122 were of indeterminate type (I-IBS). Patients with IBS were younger than HC and CNSD (IBS vs. HC: 36.6 yr ± 11.4 vs. 44.1 yr ± 13.6, p = 0.001; IBS vs. CNSD: 36.6 yr ± 11.4 vs. 42 yr ± 14.5, p = 0.003). Patients with CNSD were comparable to HC in age (42 yr ± 14.5 vs. 44.1 yr ± 13.6, p = ns). Patients with IBS were more often male than HC [108/129 (83.7%) vs. 34/51 (66.7%) p = 0.02]; gender of CNSD and HC was comparable [male 39/73 (53.4%) vs. 34/51 (66.7%) p = ns]. SIBO was commoner in CNSD than HC [16 (21.9%) vs. 1 (2%), p = 0.003], but was comparable in IBS and HC [11 (8.5%) vs. 1 (2%), p = 0.18]. Patients with CNSD more often had SIBO than IBS [16 (21.9%) vs. 11 (8.5%), p = 0.007]. Conclusions SIBO was more common in CNSD including D-IBS than other types of IBS and HC.
Kumar, Sunil; Mehrotra, Mansi; Lakshmi, CP; Misra, Asha
Excess drinking is associated with lost productivity, accidents, disability, early death, crime, neglect of family responsibilities, and personality deterioration. These and related concerns have justified special restrictions on alcoholic-beverage commerce and consumption. The nature and extent of government involvement in this arena vary widely over time and place, and are often controversial. Economists have contributed to the evaluation of alcohol
Philip Cook; Michael J. Moore
Objective: To demonstrate that small intestinal mucosal ischemia occurs during cardiopulmonary bypass by measuring serum diamine oxidase activity, an index of small intestinal mucosal ischemia, in perioerative patients undergoing cardiovascular surgery with and without cardiopulmonary bypass. Methods: Twelve successive patients who underwent coronary artery bypass grafting with cardiopulmonary bypass (Group I) were compared to 10 patients who underwent off-pump coronary
Nobuo Tsunooka; Kazutaka Maeyama; Yoshihiro Hamada; Hiroshi Imagawa; Shinji Takano; Yuji Watanabe; Kanji Kawachi
The bacterial diversity in pulque, a traditional Mexican alcoholic fermented beverage, was studied in 16S rDNA clone libraries from three pulque samples. Sequenced clones identified as Lactobacillus acidophilus, Lactobacillus strain ASF360, L. kefir, L. acetotolerans, L. hilgardii, L. plantarum, Leuconostoc pseudomesenteroides, Microbacterium arborescens, Flavobacterium johnsoniae, Acetobacter pomorium, Gluconobacter oxydans, and Hafnia alvei, were detected for the first time in pulque.
Adelfo Escalante; Mar??a Elena Rodr??guez; Alfredo Mart??nez; Agust??n López-Mungu??a; Francisco Bol??var; Guillermo Gosset
The major lipid constituent of symbiotic gram-positive bacteria in animals are phosphatidylglycerol, cardiolipin and dihexaosyl diglycerides (DH-DG), whose hydrophobic structures are characteristic of the environments, and the carbohydrate structures of DH-DGs are bacterial species-characteristic. Immunization of rabbits with intestinal lactobacilli generated antibodies against DH-DGs and their modified structures, among which Gal?1-6-substituted DH-DG, i.e., Lactobacillus tetrahexaosyl diglyceride (LacTetH-DG), reacted with antibodies more intensely than DH-DG. Whereas, from the 16S-rRNA sequence, the intestinal lactobacilli in murine digestive tracts were revealed to be L. johnsonii, in which LacTetH-DG is present at the concentration of 2.2 ng per 1?×?10(6) cells. To obtain more accurate estimates of intestinal lactobacilli in several regions of the digestive tract of mice, LacTetH-DG was detected by TLC-immunostaining with anti-Lactobacillus antisera, being found in the stomach, cecum and colon of normal breeding mice, 1.0?×?10(9), 3.5?×?10(9) and 7.4?×?10(9) cells, respectively. Administration of penicillin and streptomycin for 6 days resulted in a reduction in the number of intestinal lactobacilli, the levels being 0 %, 30 % and 4 % of the control ones in the stomach, cecum and colon, respectively, which was associated with the accumulation of the contents in the tracts from the stomach to the cecum and with diarrhea. In addition, a reduced amount of fucosyl GA1 (FGA1) and a compensatory increase in GA1 due to the reduced activity of ?1,2-fucosyltransferase in the small intestine and the enhanced discharge of FGA1 into the contents occurred in mice, probably due to the altered population of bacteria caused by administration of penicillin and streptomycin. PMID:23996013
Iwamori, Masao; Iwamori, Yuriko; Adachi, Shigeki; Nomura, Taisei
Contribution of intestinal bacterial degradation of quercetin aglycone to the promotive effects of fructooligosaccharides and di-D-fructose anhydride III (DFAIII) on quercetin-3-O-beta-glucoside (Q3G) bioavailability was examined. Male Sprague-Dawley rats were fed 0.68% Q3G diets with or without 1.5% or 3% oligosaccharides for 2 weeks. Blood levels and urinary excretion of quercetin and methylquercetin conjugates, measured by methanol extraction and LC-MS analyses, were dose-dependently and adaptively increased by the oligosaccharide supplementation with increasing cecal fermentation (Experiment 1). Degradation of Q3G and quercetin aglycone by cecal bacteria in oligosaccharide-fed rats was much lower than that in the control rats using an anaerobic culture system (Experiment 2). Using the ligated intestinal sacs of anesthetized rats, we found that the cecum possessed high absorptive capacity for quercetin derivatives (Experiment 3). These results demonstrate that feeding of the oligosaccharides strongly suppresses the bacterial degradation of quercetin aglycone in the cecum, thus largely contributing to the increased bioavailability of Q3G. PMID:19807098
Matsukawa, Noriko; Matsumoto, Megumi; Shinoki, Aki; Hagio, Masahito; Inoue, Ryo; Hara, Hiroshi
This study was conducted to relate the per- formance of broiler chickens fed diets containing growth- promoting antibiotics to changes in the intestinal microbi- ota. The technique of denaturing gradient gel electropho- resis (DGGE) of amplicons of the region V3 of 16S rDNA was used to characterize the microbiota. Two experiments were conducted, one with broilers raised in battery cages
A. A. Pedroso; J. F. M. Menten; M. R. Lambais; A. M. C. Racanicci; F. A. Longo; J. O. B. Sorbara
The efficacy of ornithine alpha-ketoglutarate (OKG) in preventing bacterial translocation and dissemination, metabolic disorders and changes in mucosal enzyme activities was assessed in a model of bacterial translocation in rats. Antibiotic decontamination was performed 4 d before intragastric inoculation with an Escherichia coli strain (10(10) bacteria/kg body). Two days later, the rats were given either a lipopolysaccharide (LPS) 0127:B8 or a saline injection and were deprived of food for 24 h. Enteral nutrition, [Osmolite, 880 kJ/(kg. d)] supplemented with either OKG (LPS + OKG) or glycine (Saline + Gly or LPS + Gly), was then given for 2 d. Urinary total nitrogen losses and 3-methylhistidine excretion were determined daily. On killing at d 3, bacterial translocation to the mesenteric lymph nodes (MLN) and dissemination to the spleen and liver were evaluated, jejunal mucosa enzyme activities were assayed and tissue free amino acids in muscles were measured. Endotoxin induced translocation from the gut lumen to the MLN in all groups, whereas dissemination occurred only in LPS-treated rats. OKG significantly reduced dissemination of the bacteria in the spleen. 3-Methylhistidine excretion was greater in the LPS + Gly group (+25%, P: < 0.05) than in either the LPS + OKG or Saline + Gly group. The group fed the OKG-enriched diet had higher muscular glutamine, ornithine and arginine concentrations than did the Gly-supplemented groups (P: < 0.05). Intestinal sucrase and aminopeptidase activities were higher in the LPS + OKG group than in the LPS + Gly group (-30%, P: < 0.05). OKG supplementation limits bacterial dissemination and metabolic changes after injury in rats and thus may be useful in the prevention of gut-derived sepsis in critically ill patients. PMID:11110843
Schlegel, L; Coudray-Lucas, C; Barbut, F; Le Boucher, J; Jardel, A; Zarrabian, S; Cynober, L
A bacterial strain BGI-1 was isolated from the gut of German cockroaches (Blattella germanica L.) and was identified as Bacillus subtilis based on 16S rDNA sequence and morphological, physiological, and biochemical characters. The strain BGI-1 inhibited the growth of Beauveria bassiana; the diameter of the inhibition zone exceeded 30 mm. Vesicles were observed in B. bassiana hyphae on the edge of the inhibition zone. Fermentation of BGI-1 reduced the conidial germination rate by 12%. Further studies demonstrated that B. bassiana infections in German cockroaches orally treated with the extracts of BGI-1 fermentation were significantly weakened. Cumulative mortality rate was 49.5% in the treatment group at the 20 d, while that of the control group was 62.3%. The study intends to understand the relationship between the intestinal flora and the cockroach. Those microbes with anti-entomopathogenic fungi activity might contribute to resisting the infection of pathogenic fungi. PMID:23448013
Huang, Y H; Wang, X J; Zhang, F; Huo, X B; Fu, R S; Liu, J J; Sun, W B; Kang, D M; Jing, X
Recent evidence suggests that translocation of bacteria and bacterial products, such as endotoxin from the intestinal lumen into the systemic circulation is a contributing factor in the pathogenesis of chronic liver diseases and the development of complications in cirrhosis. In addition to alterations in the intestinal microbiota and immune system, dysfunction of the intestinal epithelial barrier may be an important factor facilitating bacterial translocation. This review aims to provide an overview of the current evidence of intestinal epithelial barrier dysfunction in human chronic liver diseases and cirrhosis, and to discuss possible contributing factors and mechanisms. Data suggest the presence of intestinal epithelial barrier dysfunction in patients with chronic liver diseases, but are more convincing in patients with cirrhosis, especially in those with complications. The barrier dysfunction can result from both direct and indirect effects of aetiological factors, such as alcohol and obesity, which can cause chronic liver diseases and ultimately cirrhosis. On the other hand characteristics of cirrhosis itself, including portal hypertension, alterations in the intestinal microbiota, inflammation and oxidative stress can affect barrier function of both small and large intestine and may contribute to the development of complications. In conclusion, there are indications for intestinal epithelial barrier dysfunction in patients with chronic liver diseases and especially in patients with cirrhosis, which can be caused by various factors affecting both the small and large intestine. PMID:23879434
Pijls, Kirsten E; Jonkers, Daisy M A E; Elamin, Elhaseen E; Masclee, Ad A M; Koek, Ger H
Alterations in the luminal microflora and increased intestinal translocation have been reported to occur following experimental and clinical small bowel transplantation (SBT). Selective intestinal decontamination (SID) has been used to prevent luminal overgrowth and bacterial translocation. Despite the wide use of SID in clinical SBT, there are no data supporting its usefulness in this situation. Thus, the aim of this investigation was to examine the effects of cyclosporine A (CsA) and SID upon bacterial overgrowth and translocation in a swine model of SBT. Nineteen Large White female pigs weighing 30 +/- 2 kg underwent a total orthotopic SBT and were randomly allocated to one of the following experimental groups as follows: Group 1 (No. 8) CSA 25 mg/kg body weight (b.w.)/day administered subcutaneously and Cefazolin 2 g/day im. Group 2 (No. 6) received the identical immunosuppression but the Cefazolin 2 g/day im was discontinued on the 5th Postoperative Day (pod) and switched to a SID regimen consisting of Vancomycin, 1 g, Nystatin, 500,000 IU, Colistin, 1,500,000 IU, and Tobramycin, 100 mg, given through a gastrostomy tube. Group 3 (No. 5) received no immunosuppression but antibiotic consisting of Cefazolin 2 g im/day. Group 4 (No. 7) underwent a small bowel autotransplantation. Group 4 received SID as in group 2 but no immunosuppression was given. Finally, 17 normal animals were sham-operated and were used as normal controls (N group). The animals in groups 1, 2, and 4 were sacrificed on the 29th pod. Those in group 3 were sacrificed on the 7th pod.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7723317
Biffi, R; Privitera, G; Matinato, C; Pozzi, S; Marzona, L; De Rai, P; Andreoni, B; Tiberio, G; Frezza, E; Van Thiel, D H
Gastrin regulates gastric acid secretion, believed to be primarily responsible for killing ingested microbes. We examined gastric killing of gavaged E. coli in gastrin-deficient mice, which have decreased gastric acid production. Additionally, the expression of intestinal genes involved in epithelial protection were analyzed: the mucus layer glycoprotein muclin, the polymeric Ig receptor, trefoil factor 3, and small proline-rich protein 2a
Francis J. Sun; Simran Kaur; Donna Ziemer; Snigdha Banerjee; Linda C. Samuelson; Robert C. De Lisle
BACKGROUND--Nucleoside-nucleotide mixture has been shown to improve gut morphology and reduce the incidence of bacterial translocation in protein deficient mice. AIMS--To compare the reparative effect of nucleoside-nucleotide mixture and their individual components on maintenance of gut integrity and bacterial translocation based on their differential metabolism and utilisation. METHODS--ICR (CD-1) mice were randomised into eight groups of 10 animals each and fed 20% casein diet (control), protein free diet, or protein free diet supplemented with 3 M cytidine, uridine, thymidine, inosine, guanosine monophosphate, or nucleoside-nucleotide mixture for four weeks. On the fourth week, each mouse was injected lipopolysaccharide intraperitoneally (50 micrograms/500 microliters) and the incidence of bacterial translocation, caecal bacterial populations, and the ileal histology, noted 48 hours later. RESULTS--The death rate in the control group was 40% compared with 10% in the nucleoside-nucleotide mixture and 20% each in the individual components groups, respectively. Bacterial translocation to the mesenteric lymph node did occur in 100% of the surviving mice fed the control diet in comparison with 44% (nucleoside-nucleotide), 50% (cytidine), 75% (thymidine), 75% (uridine), 63% (inosine), and 63% (guanosine monophosphate). Histologically, the damage to the gut was more distinct in the protein free diet group. Villous height, crypt depth, and wall thickness in the nucleoside-nucleotide mixture group mean (SEM) (5.01 (0.34); 0.87 (0.14); 0.33 (0.10)), were respectively, higher compared with the protein free diet (3.34 (0.34); 0.61 (0.03); 0.18 (0.04)) group. In the cytidine group, crypt depth (0.86) (0.08)), and wall thickness (0.30 (0.002)) were higher. The same measurements in the components groups tended to be higher than the protein free diet group. Caecal bacterial populations were, however, similar in all groups. CONCLUSIONS--These results suggest that dietary nucleosides and nucleotides are essential nutrients for intestinal repair; nucleotides or cytidine provide a better response. Images Figure 1
Adjei, A A; Yamauchi, K; Chan, Y C; Konishi, M; Yamamoto, S
In previous studies, dietary nucleotides have been shown to improve performance in single-stomached animals by promoting the renewal of small intestine epithelial cells and by influencing the activity and composition of the microbial community in the digestive tract. The present experiment was carried out with 12 barrows weaned at the age of 18 days and fitted with a simple T-cannula at the distal ileum. To determine short-term effects of dietary yeast nucleotides, the piglets received a grain-soybean meal-based basal diet with or without supplementation of 1 g/kg of a dried yeast product containing free nucleotides. Dietary supplementation with yeast did not affect bacterial numbers in the ileum as well as ileal concentrations of individual short-chain fatty acids (SCFA), total SCFA and total lactic acid (p > 0.05). Moreover, there was no effect of supplemental yeast nucleotides on ileal ?-amylase, leucine amino peptidase, maltase and lactase activities (p > 0.05), as well as on ileal dry matter, crude protein and crude fibre digestibilities (p > 0.05). In conclusion, short-term supplementation with dietary yeast nucleotides did not affect microbial metabolite concentrations, bacterial numbers and enzyme activities in the ileal digesta as well as ileal nutrient digestibilities of newly weaned pigs. PMID:21797935
Sauer, N; Eklund, M; Roth, S; Rink, F; Jezierny, D; Bauer, E; Mosenthin, R
Intestinal epithelial cells act as innate immune sentinels, as the first cells that encounter diarrheal pathogens. They use pattern recognition molecules such as the Toll-like receptors (TLRs) to identify molecular signals found on microbes but not host cells or food components. TLRs cannot generally distinguish the molecular signals on pathogenic bacteria from those found in commensals, yet under healthy conditions epithelial immune responses are kept in check. We hypothesized that, in the setting of tissue damage or stress, intestinal epithelial cells would upregulate their responses to TLR ligands to reflect the greater need for immediate protection against pathogens. We treated Caco-2 cells with the TLR5 agonist flagellin in the presence or absence of H(2)O(2) and measured chemokine production and intracellular signaling pathways. H(2)O(2) increased flagellin-induced IL-8 (CXCL8) production in a dose-dependent manner. This was associated with synergistic phosphorylation of p38 MAP kinase and with prolonged I-kappaB degradation and NF-kappaB activation. The H(2)O(2)-mediated potentiation of IL-8 production required the activity of p38, tyrosine kinases, phospholipase Cgamma, and intracellular calcium, but not protein kinase C or protein kinase D. H(2)O(2) prolonged and augmented NF-kappaB activation by flagellin. In contrast to IL-8, CCL20 (MIP3alpha) production by flagellin was reduced by H(2)O(2), and this effect was not calcium dependent. Oxidative stress biases intestinal epithelial responses to flagellin, leading to increased production of IL-8 and decreased production of CCL20. This suggests that epithelial cells are capable of sensing the extracellular environment and adjusting their antimicrobial responses accordingly. PMID:20595617
Ivison, Sabine M; Wang, Ce; Himmel, Megan E; Sheridan, Jared; Delano, Jonathan; Mayer, Matt L; Yao, Yu; Kifayet, Arnawaz; Steiner, Theodore S
Opiates are among the most prescribed drugs for pain management. However, morphine use or abuse results in significant gut bacterial translocation and predisposes patients to serious infections with gut origin. The mechanism underlying this defect is still unknown. In this report, we investigated the mechanisms underlying compromised gut immune function and bacterial translocation following morphine treatment. We demonstrate significant bacterial translocation to mesenteric lymph node (MLN) and liver following morphine treatment in wild-type (WT) animals that was dramatically and significantly attenuated in Toll-like receptor (TLR2 and 4) knockout mice. We further observed significant disruption of tight junction protein organization only in the ileum but not in the colon of morphine treated WT animals. Inhibition of myosin light chain kinase (MLCK) blocked the effects of both morphine and TLR ligands, suggesting the role of MLCK in tight junction modulation by TLR. This study conclusively demonstrates that morphine induced gut epithelial barrier dysfunction and subsequent bacteria translocation are mediated by TLR signaling and thus TLRs can be exploited as potential therapeutic targets for alleviating infections and even sepsis in morphine-using or abusing populations.
Meng, Jingjing; Yu, Haidong; Ma, Jing; Wang, Jinghua; Banerjee, Santanu; Charboneau, Rick; Barke, Roderick A.; Roy, Sabita
Toxic shock syndrome (TSS) caused by the superantigen exotoxins of Staphylococcus aureus and Streptococcus pyogenes is characterized by robust T cell activation, profound elevation in systemic levels of multiple cytokines, including interferon-? (IFN-?), followed by multiple organ dysfunction and often death. As IFN-? possesses pro- as well as anti-inflammatory properties, we delineated its role in the pathogenesis of TSS. Antibody-mediated in vivo neutralization of IFN-? or targeted disruption of IFN-? gene conferred significant protection from lethal TSS in HLA-DR3 transgenic mice. Following systemic high dose SEB challenge, whereas the HLA-DR3.IFN-?+/+ mice became sick and succumbed to TSS, HLA-DR3.IFN-??/? mice appeared healthy and were significantly protected from SEB-induced lethality. SEB-induced systemic cytokine storm was significantly blunted in HLA-DR3.IFN-??/? transgenic mice. Serum concentrations of several cytokines (IL-4, IL-10, IL-12p40 and IL-17) and chemokines (KC, rantes, eotaxin and MCP-1) were significantly lower in HLA-DR3.IFN-??/? transgenic mice. However, SEB-induced T cell expansion in the spleens was unaffected and expansion of SEB-reactive TCR V?8+ CD4+ and CD8+ T cells was even more pronounced in HLA-DR3.IFN-??/? transgenic mice when compared to HLA-DR3.IFN-?+/+ mice. A systematic histopathological examination of several vital organs revealed that both HLA-DR3.IFN-?+/+ and HLA-DR3.IFN-??/? transgenic mice displayed comparable severe inflammatory changes in lungs, and liver during TSS. Remarkably, whereas the small intestines from HLA-DR3.IFN-?+/+ transgenic mice displayed significant pathological changes during TSS, the architecture of small intestines in HLA-DR3.IFN-??/? transgenic mice was preserved. In concordance with these histopathological changes, the gut permeability to macromolecules was dramatically increased in HLA-DR3.IFN-?+/+ but not HLA-DR3.IFN-??/? mice during TSS. Overall, IFN-? seemed to play a lethal role in the immunopathogenesis of TSS by inflicting fatal small bowel pathology. Our study thus identifies the important role for IFN-? in TSS.
Tilahun, Ashenafi Y.; Holz, Marah; Wu, Tsung-Teh; David, Chella S.; Rajagopalan, Govindarajan
This investigation studied the effects of a shift from a mixed diet to a lactovegetarian diet on some cancer-associated bacterial enzymes in human feces (beta-glucuronidase, beta-glucosidase, and sulphatase). Three months after the shift to the lactovegetarian diet, there was a significant decrease in beta-glucuronidase, beta-glucosidase, and sulphatase activities per gram feces wet weight (p less than 0.05, less than 0.05, and less than 0.001, respectively). In contrast, glucuronide and glucoside hydrolysis remained unchanged per gram dry weight, although sulphatase activity was still significantly lowered when expressed this way (p less than 0.01). However, the fecal excretion increased significantly (p less than 0.05). Part of the explanation for the decreased enzyme activities is obviously a dilution effect, because much of the increased fecal weight after the shift in diet was associated with a higher water content. The higher water content was probably due to a higher fiber intake (p less than 0.001). Thus, the results in this paper indicate that a change from a mixed diet to a lactovegetarian diet leads to a decrease in certain enzyme activities proposed to be risk factors for colon cancer. PMID:2128119
Johansson, G K; Ottova, L; Gustafsson, J A
Polyvinyl alcohol (PVA) containing the fixative mercuric chloride is considered the “gold standard” for the fixation of ova and parasites in the preparation of permanently stained smears of stool specimens. However, mercuric chloride is potentially hazardous to laboratory personnel and presents disposal problems. We compared three new alternative, nontoxic fixatives with PVA, analyzing ease of sample preparation and quality of smears. Sixty-eight fresh stool specimens were divided into aliquots and placed in each of four different fixatives: PARASAFE (PS) (Scientific Devices Laboratory, Inc., Des Plaines, Ill.), ECOFIX (EC) (Meridian Diagnostics, Inc., Cincinnati, Ohio), Proto-Fix (PF) (Alpha-Tec Systems, Inc., Vancouver, Wash.), and low-viscosity PVA fixative (PVA) (Meridian). Specimens were processed and stained according to each manufacturer's directions. Parasites were found in 31 of 68 slide preparations with PVA, 31 with PF, 30 with EC, and 30 with PS. Blastocystis hominis and Iodamoeba bütschlii were preserved in a readily identifiable state by all methods of fixation. However, some parasites were more easily identified with some of the fixatives because of differences in parasite distortion. For example, Entamoeba histolytica (Entamoeba dispar) was detected in 13 stools fixed with PF, 7 with PVA, and 6 with EC but none with PS. Likewise, Chilomastix mesnili was identified in 13 specimens fixed with PF, 8 with EC, and 5 with PVA but only 1 with PS, while Entamoeba coli was seen much less frequently with PS than with the other three fixatives. A dirty background was observed in 41% of specimens prepared with PS, whereas background quality was acceptable with other fixatives. Sample preparation was most rapid with PS, although the EC method involved the fewest steps. In conclusion, PVA and PF produced the least parasite distortion, while PS proved unsatisfactory for the identification of E. histolytica, E. coli, and C. mesnili. Both PF and EC appear to be acceptable, environmentally safe substitutes for PVA.
Jensen, B.; Kepley, W.; Guarner, J.; Anderson, K.; Anderson, D.; Clairmont, J.; De l'aune, William; Austin, E. H.; Austin, G. E.
Administration of Pediococcus acidilactici or Saccharomyces cerevisiae boulardii modulates development of porcine mucosal immunity and reduces intestinal bacterial translocation after Escherichia coli challenge.
In this study, the influence of the probiotics, Pediococcus acidilactici (PA) and Saccharomyces cerevisiae boulardii (SCB), on intestinal immune traits and resistance to enterotoxigenic Escherichia coli (ETEC) infection was evaluated in pigs. Two weeks before farrowing, 30 sows and their future litters were allocated to the following treatments: 1) control group without antibiotic or probiotic treatment (CTRL), 2) control with antibiotic (tiamulin) added to weanling feed (ABT), or litters treated with 3) PA, 4) SCB, or 5) PA+SCB from 24 h after birth. During lactation, PA, SCB, or PA+SCB were given to piglets 3 times a week by gavage. After weaning at 21 d of age, probiotics or ABT were added to the diet. Four pigs per litter were chosen to evaluate performance and blood concentrations of folic acid and vitamin B(12). Three of these were orally challenged with an ETEC strain on d 49 to 51 and killed on d 52. Three piglets from the rest of the litter were slaughtered on d 18 and 3 others on d 24. Blood, ileum, and mesenteric lymph node (MLN) samples were taken to characterize leukocyte populations, determine IgA concentrations in ileal flushes, and evaluate bacterial translocation in MLN. No treatment effect on postweaning performance and on blood concentrations of folic acid and vitamin B(12) was observed. In the ileum, the percentage of CD4(-)CD8(+low) T cells was greater (P = 0.05) in 18-d-old nursed piglets treated with PA than in those of the CTRL and PA+SCB groups. In the MLN, the percentage of CD8(+) T cells was not affected by any of the treatments at d 18 and 24 but decreased (P = 0.006) after weaning. In the blood, CD8(+) T cells were not affected by treatments or weaning. After the ETEC challenge (d 52), bacterial translocation to MLN was reduced (P = 0.05) in pigs treated with PA, SCB, PA+SCB, or ABT compared with CTRL. No treatment effect was observed on blood leukocyte populations after ETEC challenge, although a time effect (d 42 vs. 52) indicated that blood CD4(+) and gammadelta-T lymphocytes were increased (P < 0.05) on d 52 compared with d 42, whereas CD4(-)CD8(+low) T lymphocytes and monocytes were markedly reduced (P < 0.01). Finally, the IgA concentration in ileal flushes collected on d 42 and 52 was greater in SCB and CTRL piglets than in ABT and PA piglets. In conclusion, probiotics may have the potential to modulate establishment of lymphocyte populations and IgA secretion in the gut and to reduce bacterial translocation to MLN after ETEC infection. PMID:19028865
Lessard, M; Dupuis, M; Gagnon, N; Nadeau, E; Matte, J J; Goulet, J; Fairbrother, J M
The intestine is subjected to a barrage of insults from food, bacterial flora, and pathogens. Despite this constant antigenic challenge, the mucosal tissues lining the intestinal tract remain largely under control. The mechanisms regulating the homeostatic balance in the gut have been investigated for many years by many groups, but the precise nature of the regulatory control remains elusive. In this review, we provide an overview of pathways proposed to be involved in dampening the inflammatory response and maintaining the homeostatic balance in the intestine, and how these pathways may be disrupted in ulcerative colitis and Crohn's disease. PMID:20066780
Arnett, Heather A; Viney, Joanne L
The large intestine is larger and shorter than the small intestine and connects to the small intestine and the anus. Nutrient deficient material from the small intestine travels through the large intestine to the anus. This material is called feces and is excreted. Feces is made up of material that our bodies cannot break down into smaller parts to be used by the body.
Katie Hale (CSUF;)
The volume of human intestinal gas is about 200 ml, and it is derived from complex physiological processes including swallowed air, diffusion from bloodstream into the lumen, and particularly intraluminal production by chemical reactions and bacterial fermentation. Gas is continuously removed by eructation, anal evacuation, absorption through the intestinal mucosa, and bacterial consumption. More than 99% of it is composed
Davide Roccarina; Ernesto Cristiano Lauritano; Maurizio Gabrielli; Francesco Franceschi; Veronica Ojetti; Antonio Gasbarrini
Background ?-galactosidase has been widely used in animal husbandry to reduce anti-nutritional factors (such as ?-galactoside) in feed. Intestine-specific and substrate inducible expression of ?-galactosidase would be highly beneficial for transgenic animal production. Methods To achieve the intestine-specific and substrate inducible expression of ?-galactosidase, we first identified intestine-specific promoters by comparing the transcriptional activity and tissue specificity of four intestine-specific promoters from human intestinal fatty acid binding protein, rat intestinal fatty acid binding protein, human mucin-2 and human lysozyme. We made two chimeric constructs combining the promoter and enhancer of human mucin-2, rat intestinal trefoil factor and human sucrase-isomaltase. Then a modified lac operon system was constructed to investigate the induction of ?-galactosidase expression and enzyme activity by isopropyl ?-D-1-thiogalactopyranoside (IPTG) and an ?-galactosidase substrate, ?-lactose. We declared that the research carried out on human (Zhai Yafeng) was in compliance with the Helsinki Declaration, and experimental research on animals also followed internationally recognized guidelines. Results The activity of the human mucin-2 promoter was about 2 to 3 times higher than that of other intestine-specific promoters. In the lac operon system, the repressor significantly decreased (P < 0.05) luciferase activity by approximately 6.5-fold and reduced the percentage of cells expressing green fluorescent protein (GFP) by approximately 2-fold. In addition, the expression level of ?-galactosidase mRNA was decreased by 6-fold and ?-galactosidase activity was reduced by 8-fold. In line with our expectations, IPTG and ?-lactose supplementation reversed (P < 0.05) the inhibition and produced a 5-fold increase of luciferase activity, an 11-fold enhancement in the percentage of cells with GFP expression and an increase in ?-galactosidase mRNA abundance (by about 5-fold) and ?-galactosidase activity (by about 7-fold). Conclusions We have successfully constructed a high specificity inducible lac operon system in an intestine-derived cell line, which could be of great value for gene therapy applications and transgenic animal production.
Background Following Helicobacter pylori eradication in idiopathic parkinsonism (IP), hypokinesia improved but flexor-rigidity increased. Small intestinal bacterial-overgrowth (SIBO) is a candidate driver of the rigidity: hydrogen-breath-test-positivity is common in IP and case histories suggest that Helicobacter keeps SIBO at bay. Methods In a surveillance study, we explore relationships of IP-facets to peripheral immune/inflammatory-activation, in light of presence/absence of Helicobacter infection (urea-breath- and/or stool-antigen-test: positivity confirmed by gastric-biopsy) and hydrogen-breath-test status for SIBO (positivity: >20 ppm increment, 2 consecutive 15-min readings, within 2h of 25G lactulose). We question whether any relationships found between facets and blood leukocyte subset counts stand in patients free from anti-parkinsonian drugs, and are robust enough to defy fluctuations in performance consequent on short t½ therapy. Results Of 51 IP-probands, 36 had current or past Helicobacter infection on entry, 25 having undergone successful eradication (median 3.4 years before). Thirty-four were hydrogen-breath-test-positive initially, 42 at sometime (343 tests) during surveillance (2.8 years). Hydrogen-breath-test-positivity was associated inversely with Helicobacter-positivity (OR 0.20 (95% CI 0.04, 0.99), p<0.05). In 38 patients (untreated (17) or on stable long-t½ IP-medication), the higher the natural-killer count, the shorter stride, slower gait and greater flexor-rigidity (by mean 49 (14, 85) mm, 54 (3, 104) mm.s-1, 89 (2, 177) Nm.10-3, per 100 cells.?l-1 increment, p=0.007, 0.04 & 0.04 respectively, adjusted for patient characteristics). T-helper count was inversely associated with flexor-rigidity before (p=0.01) and after adjustment for natural-killer count (-36(-63, -10) Nm.10-3 per 100 cells.?l-1, p=0.007). Neutrophil count was inversely associated with tremor (visual analogue scale, p=0.01). Effect-sizes were independent of IP-medication, and not masked by including 13 patients receiving levodopa (except natural-killer count on flexor-rigidity). Cellular associations held after allowing for potentially confounding effect of hydrogen-breath-test or Helicobacter status. Moreover, additional reduction in stride and speed (68 (24, 112) mm & 103 (38, 168) mm.s-1, each p=0.002) was seen with Helicobacter-positivity. Hydrogen-breath-test-positivity, itself, was associated with higher natural-killer and T-helper counts, lower neutrophils (p=0.005, 0.02 & 0.008). Conclusion We propose a rigidity-associated subordinate pathway, flagged by a higher natural-killer count, tempered by a higher T-helper, against which Helicobacter protects by keeping SIBO at bay.
\\u000a Diarrhea related to alcohol abuse may be either acute or chronic. Acute diarrheas are the result of dietary indiscretion,\\u000a transient anatomic or motility changes of the stomach or small intestine, impaired nutrient absorption, mucosal barrier function\\u000a or pancreatic secretion as well as hormonal\\/cytokine abnormalities related to alcohol hangover. Chronic diarrheas may result\\u000a from alcohol withdrawal, pancreatic or hepatobiliary dysfunction, morphologic
Nischita K. Reddy; Ashwani Singal; Don W. Powell
Salmonella dublin is a veterinary pathogen which rarely causes human illness, although reported human isolates have increased over the past two decades. This serovar of salmonella is unusually invasive and life-threatening, although the clinical pattern of human infection is not well known. We describe a 51-year-old cirrhotic patient who presented with severe liver failure, chronic diarrhoea and left-sided segmental colitis. Radiological and endoscopic findings suggested Crohn's colitis. During the hospital stay he developed a spontaneous bacterial peritonitis (SBP) and S. dublin was isolated in the ascitic fluid. Our report supports the view that this salmonella serovar should be kept in mind as a rare cause of SBP in cirrhotic patients, especially in those cases with chronic colitis resembling Crohn's disease. PMID:11396541
Jiménez-Sáenz, M; Gómez-Rodriguez, B J; Carmona, I; Rebollo, J; Torres, Y; Rodriguez-Baños, J; Herrerías-Gutiérrez, J M
Smaller food particles move from the stomach to the small intestine. The small intestine is a long tube (like a garden hose), located just below the stomach. Most absorption of nutrients takes place in the small intestine (see absorption illustration). Keep in mind that the intestines are coiled like a snake inside of our bodies and are many feet long.
Katie Hale (CSUF;)
Nonhuman primates fed folic acid-deficient diets +/- 30% kcal ethanol were used to determine alcohol effects on megaloblastic anemia development and folate bioavailability. Lower hemoglobin (Hb) and red blood cell (RBC) counts and higher mean corpuscular volume (MCV) occurred after 13 wk in alcohol-fed monkeys, later in controls. Plasma, RBC, and liver folate declined and urinary formiminoglutamic acid (FIGLU) was elevated in both groups with FIGLU increasing more among alcohol-fed monkeys at 38 wk. After 40 wk, the bioavailability of oral /sup 3/H-folic acid was investigated and showed increased fecal and reduced urinary tritium excretion in alcohol-fed monkeys compared with controls while plasma uptake and liver and whole body tritium retention were similar in both groups. These observations demonstrate that chronic alcohol consumption impairs folate coenzymes, accelerates appearance of hematologic indices of megaloblastic anemia, and causes possible malabsorption of enterohepatically circulated folates in folate deficiency even when other essential nutrients are provided.
Blocker, D.E.; Thenen, S.W.
Consumption of large quantities of alcoholic beverages leads to disturbances in the intestinal absorption of nutrients including several vitamins. The inhibition of the absorption of sodium and water caused by alcohol contributes to the tendency in alcoholics to develop diarrhoea. Excessive alcohol consumption (even a single episode) can result in duodenal erosions and bleeding and mucosal injury in the upper
J Christian Bode
Intestinal helminthiases are infections in which adult helminths (nematodes, trematodes, cestodes) parasitize the intestine. In Central Europe intestinal helminthiases are usually acquired during travel or are imported by migrants. In contrast, in developing countries, intestinal helminthiases are highly prevalent. The mode of transmission and the clinical picture depend on the helminth species. Special laboratory methods are needed to diagnose the different intestinal helminthiases. Nematodes are usually treated with the benzimidazoles mebendazole and albendazole. Ivermectin, a macrocyclic lactone, is an alternative. Praziquanel is the drug of choice for the treatment of intestinal cestodes. PMID:20687462
Intestinal dendritic cells are continually exposed to ingested microorganisms and high concentrations of endogenous bacterial flora. These cells can be activated by infectious agents and other stimuli to induce T-cell responses and to produce chemokines which recruit other cells to the local environment. Bacterial probiotics are of increasing use against intestinal disorders such as inflammatory bowel disease. They act as
Maureen Drakes; Thomas Blanchard; Steven Czinn
A small scale study on the effects of oral administration of the ?-glucan produced by Aureobasidium pullulans on milk quality and cytokine expressions of Holstein cows, and on bacterial flora in the intestines of Japanese black calves
Background The ?–(1???3),(1???6)-D-glucan extracellularly produced by Aureobasidium pullulans exhibits immunomodulatory activity, and is used for health supplements. To examine the effects of oral administration of the ?–(1???3),(1???6)-D-glucan to domestic animals, a small scale study was conducted using Holstein cows and newborn Japanese Black calves. Findings Holstein cows of which somatic cell count was less than 3 x 105/ml were orally administered with or without the ?-(1???3),(1???6)-D-glucan-enriched A. pullulans cultured fluid (AP-CF) for 3?months, and the properties of milk and serum cytokine expression were monitored. Somatic cell counts were not significantly changed by oral administration of AP-CF, whereas the concentration of solid non fat in the milk tended to increase in the AP-CF administered cows. The results of cytokine expression analysis in the serum using ELISA indicate that the expressions of tumor necrosis factor-? (TNF-?) and interleukin (IL)-6 in all cows which were orally administered with AP-CF became slightly lower than that of control cows after the two-month treatment. On the other hand, IL-8 expression tended to indicate a moderately higher level in all treated cows after the three-month administration of AP-CF in comparison with that of the control cows. Peripartum Japanese Black beef cows and their newborn calves were orally administered with AP-CF, and bacterial flora in the intestines of the calves were analyzed by T-RFLP (terminal restriction fragment length polymorphism). The results suggest that bacterial flora are tendentiously changed by oral administration of AP-CF. Conclusions Our data indicated the possibility that oral administration of the ?–(1???3),(1???6)-D- glucan produced by A. pullulans affects cytokine expressions in the serum of Holstein cows, and influences bacterial flora in the intestines of Japanese Black calves. The findings may be helpful for further study on the efficacies of oral administration of ?-(1???3),(1???6)-D-glucans on domestic animals.
The bacterial storage polymer poly-?-hydroxybutyrate (PHB) has the potential to be used as an alternative anti-infective strategy\\u000a for aquaculture rearing. In this research, the effects of (partially) replacing the feed of European sea bass juveniles with\\u000a PHB were investigated. During a 6-week trial period, the PHB showed the ability to act as an energy source for the fish. This\\u000a indicated
Peter De Schryver; Amit Kumar Sinha; Prabesh Singh Kunwar; Kartik Baruah; Willy Verstraete; Nico Boon; Gudrun De Boeck; Peter Bossier
AIM: To investigate the intestinal barrier changes in rats with CCl4-induced portal hypertension. METHODS: The permeability of intestinal barrier detected by Lanthanum as a tracer was evaluated in rats. Bacterial translocation and plasma endotoxin were also determined. RESULTS: The incidence of bacterial translocation was 85% in rats with CCl4-induced portal hypertension, which was signifi cantly higher than that in control
Guo-Xiang Yao; Zhong-Yi Shen; Xin-Bo Xue; Zhen Yang
This investigation studied the effects of a shift from a well-balanced mixed diet to a lacto-vegetarian diet on the mutagenic activity in urine and feces and on some cancer-associated bacterial enzymes in human feces (beta-glucuronidase, beta-glucosidase, and sulphatase). Three months after the shift to the lacto-vegetarian diet, there was a significant decrease in mutagenic activity in urine and feces, beta-glucuronidase, beta-glucosidase, and sulphatase per gram feces wet weight. In contrast, the fecal mutagenic activity and the enzyme activities remained unchanged if expressed per daily output. However, the urinary mutagenic activity expressed as total daily output decreased. Part of the explanation for the decreased fecal mutagenic activity and the decreased enzyme activities is obviously a dilution effect, because much of the increased fecal weight after the shift in diet was associated with a higher water content. PMID:9167043
Johansson, G; Holmén, A; Persson, L; Högstedt, B; Wassén, C; Ottova, L; Gustafsson, J A
Background: Intestinal malabsorption in the elderly is infrequent, and clinical features are muted so that the diagnosis is often missed. Physiologic changes with aging are restricted to altered absorption of calcium and perhaps zinc and magnesium; however, achlorhydria can lead to impaired absorption of vitamin B12, folic acid, and calcium. Methods and Results: Small bowel bacterial overgrowth occurs more commonly
Peter R. Holt
Macrophages reside in every tissue of the body and play an important role in maintaining homeostasis. The intestinal mucosa is the largest immune organ and harbors macrophages in abundance. Dysfunction of intestinal macrophages is characteristic of patients with certain inflammatory bowel diseases. Although intestinal macrophages exhibit hyporesponsiveness to foreign substances, including various bacterial products, their physiological functions are unknown, but may be related to the contribution of intestinal bacteria to the maintenance of various physiological functions of the host. Moreover, recent reports suggest that there are associations between intestinal microbiota and the onset of pathologies, such as diverse metabolic syndromes, depression, and cancer. Evidence indicates that the host's immune response to intestinal microbiota may be etiologically-linked to these diseases; however, the mechanisms are poorly understood. In the present review, we discuss the possibility that intestinal microbiota influence health through the function of intestinal macrophages. PMID:23780969
Nakata, Kazue; Yamamoto, Mai; Inagawa, Hiroyuki; Soma, Gen-Ichiro
Clinical investigation of the small bowel at The Mount Sinai Hospital began with David Adlersberg's arrival in 1931. His research interests were in bile acids, cholesterol, carotene, and vitamin A. In 1952, he was given a Nutrition Laboratory and later, a Nutrition Clinic. His vitamin A tolerance test and interest in malabsorption led him to a comprehensive study of sprue, the separation of the tropical and non-tropical forms, and their different etiologies and treatments. Adlersberg's work was complemented by (a) Marshak and Wolf's radiologic examination of the small bowel (especially in sprue and other malabsorption disorders); (b) Gerson s perfusion experiments; and (c) Friedman, Waye and Wolf's motility studies. Lieber and his colleagues explored the deleterious effects of alcohol on the function and structure of the small intestine. Gerson explored the nutrition of patients with Crohn's disease of the small intestine, especially after extensive resection or bypass leading to ascorbic and folic acid deficiencies and hypergastrinemia. PMID:10828909
Gerson, C D
PURPOSE: Complications of intestinal malrotation are familiar to pediatric surgeons but are rarely encountered by those caring strictly for adults. The aim of this study was to review our experience with disorders of intestinal rotation in adult patients and to emphasize the clinical presentation, radiographic features, and results of surgical treatment. METHODS: Ten adult patients (mean age, 42 (range, 22–73)
David W. Dietz; R. Matthew Walsh; Sharon Grundfest-Broniatowski; Ian C. Lavery; Victor W. Fazio; David P. Vogt
|Intestinal parasites have become a serious public health problem in tropical countries because of the climate and the difficulty of achieving efficient hygiene. The objectives of this journal issue are to increase awareness of the individual and collective repercussions of intestinal parasites, describe the current conditions of contamination and…
Lagardere, Bernard; Dumburgier, Elisabeth
Background Bile acid reclamation following ileo-cecal resection (ICR) may prevent colonic mucosa from chronic injury. In this study, we hypothesized that in a murine model of ICR the remnant colon would upregulate the cellular machinery necessary for BA reclamation and would do so in an FXR- and bacteria-dependent manner. Methods Conventional (WT), conventional FXR knockout (FXR null) and germ free (GF) mice were randomized to undergo either ICR or sham operation. The ascending colon was harvested for histology & immunohistochemistry and changes in bile acid homeostatic gene expression determined by RT-PCR 7d following surgery. Results Following ICR WT mice showed significant increases in the expression of genes regulating bile acid transport including IBABP, Asbt, Ost? and FGF 15. Increased expression of IBABP and Asbt was confirmed by immunohistochemistry. Induction of bile acid transport genes was absent or attenuated in FXR null and GF mice. Conclusion Bacterial dependent up regulation of IBABP is FXR mediated in the colon following ICR. Mice lacking microbiota (GF) or FXR are unable to increase the expression of IBABP or FGF 15.
Dekaney, Christopher M.; von Allmen, Douglas C.; Garrison, Aaron P.; Rigby, Rachael J.; Lund, P. Kay; Henning, Susan J.; Helmrath, Michael A.
The biodegradation of chloroallyl alcohols by pure and mixed bacterial cultures was investigated. Only 2-chloroallyl alcohol and cis- and trans-3-chloroallyl alcohol served as growth substrate for pure cultures. The other chloroallyl alcohols could be cometabolically degraded during growth on 2-chloroallyl alcohol. Cometabolic degradation of trichloroallyl alcohol, which was the most recalcitrant congener, by a Pseudomonas strain isolated on 2-chloroallyl alcohol
J. J. Waarde; R. Kok; D. B. Janssen
In infants suffering from protein-calorie malnutrition, the decreased intestinal mucosal lactase specific activity could be due either to the protein-calorie malnutrition or to the commonly associated enteritis (viral or bacterial) and intestinal parasites. We studied intestinal mucosal disaccharidase (lactase, sucrase, and maltase) specific activity in suckling (1 and 2 wk old), weanling (3 wk old), and postweaning (4 and 6 wk old) control and growth-retarded (malnourished) rats. Growth retardation was induced by feeding mother rats and postweaning rats a diet deficient in protein. In the malnourished rats, with few exceptions, specific activity of the disaccharidases in the intestinal mucosa were similar to those in the corresponding control groups of rats. However, because of marked mucosal atrophy total intestinal mucosal disaccharidase activities were more than 50% lower in the malnourished rats. These findings suggest that the specific activity of the intestinal mucosal disaccharidases is not affected by malnutrition per se. PMID:6792898
Jambunathan, L R; Neuhoff, D; Younoszai, M K
Tertiary alcohols, such as tert-butyl alcohol (TBA) and tert-amyl alcohol (TAA) and higher homologues, are only slowly degraded microbially. The conversion of TBA seems to proceed via hydroxylation to 2-methylpropan-1,2-diol, which is further oxidized to 2-hydroxyisobutyric acid. By analogy, a branched pathway is expected for the degradation of TAA, as this molecule possesses several potential hydroxylation sites. In Aquincola tertiaricarbonis L108 and Methylibium petroleiphilum PM1, a likely candidate catalyst for hydroxylations is the putative tertiary alcohol monooxygenase MdpJ. However, by comparing metabolite accumulations in wild-type strains of L108 and PM1 and in two mdpJ knockout mutants of strain L108, we could clearly show that MdpJ is not hydroxylating TAA to diols but functions as a desaturase, resulting in the formation of the hemiterpene 2-methyl-3-buten-2-ol. The latter is further processed via the hemiterpenes prenol, prenal, and 3-methylcrotonic acid. Likewise, 3-methyl-3-pentanol is degraded via 3-methyl-1-penten-3-ol. Wild-type strain L108 and mdpJ knockout mutants formed isoamylene and isoprene from TAA and 2-methyl-3-buten-2-ol, respectively. It is likely that this dehydratase activity is catalyzed by a not-yet-characterized enzyme postulated for the isomerization of 2-methyl-3-buten-2-ol and prenol. The vitamin requirements of strain L108 growing on TAA and the occurrence of 3-methylcrotonic acid as a metabolite indicate that TAA and hemiterpene degradation are linked with the catabolic route of the amino acid leucine, including an involvement of the biotin-dependent 3-methylcrotonyl coenzyme A (3-methylcrotonyl-CoA) carboxylase LiuBD. Evolutionary aspects of favored desaturase versus hydroxylation pathways for TAA conversion and the possible role of MdpJ in the degradation of higher tertiary alcohols are discussed.
Schuster, Judith; Schafer, Franziska; Hubler, Nora; Brandt, Anne; Rosell, Monica; Hartig, Claus; Harms, Hauke; Muller, Roland H.
Role of intestinal epithelial cells in the host secretory response to infection by invasive bacteria. Bacterial entry induces epithelial prostaglandin h synthase-2 expression and prostaglandin E2 and F2alpha production.
Increased intestinal fluid secretion is a protective host response after enteric infection with invasive bacteria that is initiated within hours after infection, and is mediated by prostaglandin H synthase (PGHS) products in animal models of infection. Intestinal epithelial cells are the first host cells to become infected with invasive bacteria, which enter and pass through these cells to initiate mucosal, and ultimately systemic, infection. The present studies characterized the role of intestinal epithelial cells in the host secretory response after infection with invasive bacteria. Infection of cultured human intestinal epithelial cell lines with invasive bacteria, but not noninvasive bacteria, is shown to induce the expression of one of the rate-limiting enzymes for prostaglandin formation, PGHS-2, and the production of PGE2 and PGF2alpha. Furthermore, increased PGHS-2 expression was observed in intestinal epithelial cells in vivo after infection with invasive bacteria, using a human intestinal xenograft model in SCID mice. In support of the physiologic importance of epithelial PGHS-2 expression, supernatants from bacteria-infected intestinal epithelial cells were shown to increase chloride secretion in an in vitro model using polarized epithelial cells, and this activity was accounted for by PGE2. These studies define a novel autocrine/paracrine function of mediators produced by intestinal epithelial cells in the rapid induction of increased fluid secretion in response to intestinal infection with invasive bacteria.
Eckmann, L; Stenson, W F; Savidge, T C; Lowe, D C; Barrett, K E; Fierer, J; Smith, J R; Kagnoff, M F
Several studies indicate the importance of colonic microbiota in metabolic and inflammatory disorders and importance of diet on microbiota composition. The effects of alcohol, one of the prominent components of diet, on colonic bacterial composition is largely unknown. Mounting evidence suggests that gut-derived bacterial endotoxins are cofactors for alcohol-induced tissue injury and organ failure like alcoholic liver disease (ALD) that only occur in a subset of alcoholics. We hypothesized that chronic alcohol consumption results in alterations of the gut microbiome in a subgroup of alcoholics, and this may be responsible for the observed inflammatory state and endotoxemia in alcoholics. Thus we interrogated the mucosa-associated colonic microbiome in 48 alcoholics with and without ALD as well as 18 healthy subjects. Colonic biopsy samples from subjects were analyzed for microbiota composition using length heterogeneity PCR fingerprinting and multitag pyrosequencing. A subgroup of alcoholics have an altered colonic microbiome (dysbiosis). The alcoholics with dysbiosis had lower median abundances of Bacteroidetes and higher ones of Proteobacteria. The observed alterations appear to correlate with high levels of serum endotoxin in a subset of the samples. Network topology analysis indicated that alcohol use is correlated with decreased connectivity of the microbial network, and this alteration is seen even after an extended period of sobriety. We show that the colonic mucosa-associated bacterial microbiome is altered in a subset of alcoholics. The altered microbiota composition is persistent and correlates with endotoxemia in a subgroup of alcoholics.
Mutlu, Ece A.; Gillevet, Patrick M.; Rangwala, Huzefa; Sikaroodi, Masoumeh; Naqvi, Ammar; Engen, Phillip A.; Kwasny, Mary; Lau, Cynthia K.
After ingestion via contaminated food or water, enterohaemorrhagic E. coli colonises the intestinal mucosa and produces Shiga toxins (Stx). No Stx-specific secretion system has been described so far, and it is assumed that Stx are released into the gut lumen after bacterial lysis. Human intestinal epithelium does not express the Stx receptor Gb3 or other Stx binding sites, and it remains unknown how Stx cross the intestinal epithelial barrier and gain access to the systemic circulation. This review summarises current knowledge about the influence of the intestinal environment on Stx production and release, Stx interaction with intestinal epithelial cells and intracellular uptake, and toxin translocation into underlying tissues. Furthermore, it highlights gaps in understanding that need to be addressed by future research.
This concise survey presents some of the highlights of modern research on drinking and alcoholism, as based on technical articles published in the scientific literature and the views expressed by leading authorities in the field. Contents include discussions about: (1) the nature and scope of the problem; (2) the chemical composition of alcoholic…
National Inst. of Mental Health (DHEW), Chevy Chase, MD. National Clearinghouse for Mental Health Information.
Opinion statement The most common symptoms associated with intestinal gas are excessive eructation, flatulence, and abdominal bloating and distention.\\u000a Unfortunately, few therapies have been shown to be effective in treating these symptoms. Excessive eructation can be treated\\u000a by decreasing excessive air swallowing. Bloating and gaseous distension can improve in some patients by avoiding foods containing\\u000a partially digested or absorbed polysaccharides, by
Rebecca N. Fink; Anthony J. Lembo
Background Non-alcoholic steatohepatitis (NASH) is a serious form of non-alcoholic fatty liver disease (NAFLD), associated with obesity and insulin resistance. Previous studies suggested that intestinal bacteria produced more alcohol in obese mice than lean animals. Methodology/Principal Findings To investigate whether alcohol is involved in the pathogenesis of NASH, the expression of inflammation, fibrosis and alcohol metabolism related genes in the liver tissues of NASH patients and normal controls (NCs) were examined by microarray (NASH, n?=?7; NC, n?=?4) and quantitative real-time PCR (NASH, n?=?6; NC, n?=?6). Genes related to liver inflammation and fibrosis were found to be elevated in NASH livers compared to normal livers. The most striking finding is the increased gene transcription of alcohol dehydrogenase (ADH) genes, genes for catalase and cytochrome P450 2E1, and aldehyde dehydrogenase genes. Immunoblot analysis confirmed the increased expression of ADH1 and ADH4 in NASH livers (NASH, n?=?9; NC, n?=?4). Conclusions/Significance The augmented activity of all the available genes of the pathways for alcohol catabolism suggest that 1) alcohol concentration was elevated in the circulation of NASH patients; 2) there was a high priority for the NASH livers to scavenge alcohol from the circulation. Our data is the first human evidence that suggests alcohol may contribute to the development of NAFLD.
Baker, Susan S.; Baker, Robert D.; Liu, Wensheng; Nowak, Norma J.; Zhu, Lixin
BACKGROUND: Intestinal parasitoses is a clinical problem in the developing world and severe parasitaemia may be associated with retroviruses. OBJECTIVE: Studies on intestinal parasitoses were conducted in Dominica, and the health implications in an HTLV-1 endemic area were discussed. METHOD OF STUDY: A retrospective study of data of stool samples analysed at the parasitology unit of the medical laboratory services of Princess Margaret Hospital, Dominica, was conducted in January-December 1999. RESULTS: Parasites were found in 393 out of 3,752 stool samples (10.47%). The main parasites were Entamoeba coli, 1.4% (51/3,752); hookworm, 1.5% (56/3,752); Giardia lamblia, 1.4% (51/3,752); Strongyloides stercoralis, 1.0% (37/3,752); Ascaris lumbricoides, 0.8% (28/3,752); and Trichuris trichiura, 0.9% (34/3,752). CONCLUSION: Intestinal parasites are still endemic in Dominica, but significant reduction in prevalence has occurred over the last two decades.
Adedayo, Olayinka; Nasiiro, Robert
Background The intestinal chronic rejection (CR) is the major limitation to long-term survival of transplanted organs. This study aimed to investigate the interaction between intestinal microbiota and epithelial integrity in chronic rejection of intestinal transplantation, and to find out whether fish oil enhances recovery of intestinal microbiota and epithelial integrity. Methods/Principal Findings The luminal and mucosal microbiota composition of CR rats were characterized by DGGE analysis at 190 days after intestinal transplant. The specific bacterial species were determined by sequence analysis. Furthermore, changes in the localization of intestinal TJ proteins were examined by immunofluorescent staining. PCR-DGGE analysis revealed that gut microbiota in CR rats had a shift towards Escherichia coli, Bacteroides spp and Clostridium spp and a decrease in the abundance of Lactobacillales bacteria in the intestines. Fish oil supplementation could enhance the recovery of gut microbiota, showing a significant decrease of gut bacterial proportions of E. coli and Bacteroides spp and an increase of Lactobacillales spp. In addition, CR rats showed pronounced alteration of tight junction, depicted by marked changes in epithelial cell ultrastructure and redistribution of occuldin and claudins as well as disruption in TJ barrier function. Fish oil administration ameliorated disruption of epithelial integrity in CR, which was associated with an improvement of the mucosal structure leading to improved tight junctions. Conclusions/Significance Our study have presented novel evidence that fish oil is involved in the maintenance of epithelial TJ integrity and recovery of gut microbiota, which may have therapeutic potential against CR in intestinal transplantation.
Li, Qiurong; Zhang, Qiang; Wang, Chenyang; Tang, Chun; Zhang, Yanmei; Li, Ning; Li, Jieshou
BACKGROUND: Cystic fibrosis (CF) is caused by mutations in the CFTR gene that impair the function of CFTR, a cAMP-regulated anion channel. In the small intestine loss of CFTR function creates a dehydrated, acidic luminal environment which is believed to cause an accumulation of mucus, a phenotype characteristic of CF. CF mice have small intestinal bacterial overgrowth, an altered innate
Robert C De Lisle; Racquel Mueller; Eileen Roach
Mucosal surfaces of the gut are colonized by large numbers of heterogeneous bacteria that contribute to intestinal health and disease. In genetically susceptible individuals, a 'pathogenic community' may arise, whereby abnormal gut flora contributes to alterations in the mucosa and local immune system leading to gastrointestinal disease. These diseases include enteric infections, such as Clostridium difficile infection, small intestinal bacterial
Herbert L. DuPont; Andrew W. DuPont
Background and AimsCeliac disease (CD) is a chronic inflammatory disorder of the small intestine that is induced by dietary wheat gluten proteins (gliadins) in genetically predisposed individuals. The overgrowth of potentially pathogenic bacteria and infections has been suggested to contribute to CD pathogenesis. We aimed to study the effects of gliadin and various intestinal bacterial strains on mucosal barrier integrity,
Jana Cinova; Giada de Palma; Renata Stepankova; Olga Kofronova; Miloslav Kverka; Yolanda Sanz; Ludmila Tuckova; François Leulier
The normal intestinal flora is required for the development of intestinal inflammation in animal models of inflammatory bowel disease (IBD). In humans, several studies indicated a potential association of Escherichia coli (E. coli) with IBD. In addition, we have shown that T-cell clones of IBD patients cross react toward different enteric bacterial species and thus likely respond to conserved bacterial
A Ergin; T Adam; K Büssow; A Thiel; J Sieper; R Duchmann
BACKGROUND: Glutathione, the main antioxidant of intestinal epithelial cells, is suggested to play an important role in gut barrier function and prevention of inflammation-related oxidative damage as induced by acute bacterial infection. Most studies on intestinal glutathione focus on oxidative stress reduction without considering functional disease outcome. Our aim was to determine whether depletion or maintenance of intestinal glutathione changes
Marleen TJ van Ampting; Arjan J Schonewille; Carolien Vink; Robert Jan M Brummer; Roelof Meer; Ingeborg MJ Bovee-Oudenhoven
The small intestine, like the rest of the gastrointestinal tract, is an intelligent organ. It generates a wide variety of motor patterns to meet motility requirements in different situations. Its basic motor function after a meal is to mix the chyme with exocrine and intestinal secretions, agitate its contents to uniformly and evenly expose them to the mucosal surface, and to propel them distally at a rate that allows optimal absorption of food components, and reabsorption of bile. Most of these functions are performed by individual phasic contractions. In humans, the phasic contractions are largely disorganized in time and space. These contractions may cause mixing and agitation of luminal contents with slow distal propulsion. Occasionally, an individual contraction of large amplitude and long duration migrates over several centimeters and may rapidly propel the contents over this distance. In general, the spatial and temporal relationships of individual phasic contractions become less organized distally, resulting in a slower propulsion rate in the distal small intestine than in the proximal small intestine. The migrating clustered contractions generated after a meal may also be propulsive, but because of their unpredictable and irregular occurrence, their precise role in postprandial propulsion is incompletely understood. Rapidly migrating contractions may occur when the electrical control activity is obliterated by pharmacologic agents or during parasitic infections. Their effects on motility are not known yet. Between meals, when digestion is complete, the small intestine generates migrating motor complexes that help keep the small intestine clean by dislodging debris from the villi and dumping them into the colon. This may prevent decay of these materials in the small intestine and limit their contribution to bacterial overgrowth. Giant migrating contractions may perform a similar function in the distal small intestine as well as return any refluxed fecal material back to the colon. However, the major role of giant migrating contractions may be, in pathologic states, associated with abdominal cramping and diarrhea. Giant migrating contractions are associated with mass movements. Vomiting is preceded by a retrograde giant contraction. This contraction rapidly empties the contents of the proximal half of small intestine into the stomach in preparation for vomitus expulsion by contraction of abdominal and diaphragmatic muscles. The three basic mechanisms of control of spatial and temporal patterns of contractions are myogenic, neural, and chemical.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2668175
Sarna, S K; Otterson, M F
The term bacterial (microbial) fertilizers refers to preparations containing primarily active strains of the microorganisms mainly bacteria in sufficient numbers. This report covers various aspects of bacterial fertilizers: Nitrogen Preparation and Usage;...
W. V. B. Sundra Rao
The lower intestine of mammals is colonised by a dense flora composed mainly of non-pathogenic commensal bacteria. These intestinal\\u000a bacteria have a wide-ranging impact on host immunity and physiology. One adaptation following intestinal colonisation is increased\\u000a production and secretion of polyspecific intestinal IgA. In contrast to the strong mucosal immune response to bacterial colonisation,\\u000a the systemic immune system remains ignorant
A. J. Macpherson
The most common symptoms associated with intestinal gas are excessive eructation, flatulence, and abdominal bloating and distention. Unfortunately, few therapies have been shown to be effective in treating these symptoms. Excessive eructation can be treated by decreasing excessive air swallowing. Bloating and gaseous distension can improve in some patients by avoiding foods containing partially digested or absorbed polysaccharides, by taking replacement enzymes (such as alfa-galactosidase or lactase), or by taking antibiotics directed toward altering the colonic flora. Activated charcoal or prokinetic agents (such as tegaserod and metoclopramide) also can be effective options in some patients. For noxious odor associated with flatus, bismuth subsalicylate or the charcoal cushion may improve patients' symptoms. PMID:11469992
Fink, Rebecca N.; Lembo, Anthony J.
Influence of intestinal bacterial decontamination using metronidazole and ciprofloxacin or ciprofloxacin alone on the development of acute graft-versus-host disease after marrow transplantation in patients with hematologic malignancies: final results and long-term follow-up of an open-label prospective randomized trial.
In a single-center open-label prospective study, a total of 134 marrow transplant recipients with hematologic malignancies were randomly assigned to a bacterial decontamination medication using metronidazole and ciprofloxacin (n = 68) or ciprofloxacin alone (n = 66) during 5 weeks posttransplant. The development of grades II to IV acute graft-versus-host disease (GVHD) was defined as the primary study endpoint. According to the intention-to-treat, 17 patients (25%) randomized to the combined decontamination medication and 33 patients (50%) randomized to ciprofloxacin alone developed grades II to IV GVHD (P <.002). The higher frequency of grades II to IV acute GVHD in patients randomized to ciprofloxacin alone resulted from a more than twofold increased number of patients developing liver or intestinal involvement with acute GVHD compared with patients randomized to the combined decontamination medication (P <.003). The influence of the study medication on grades II to IV acute GVHD was significant only in recipients of transplants from genotypically HLA-identical sibling donors (n = 80), whereas in recipients of transplants from donors other than HLA-identical siblings (n = 54), grades II to IV acute GVHD frequencies between the study arms were not significantly different. The combined decontamination was associated with a significant reduction of culture growth of intestinal anaerobic bacteria during 5 weeks posttransplant (P <. 00001). In addition, the number of cultures with growth of anaerobic bacteria (P <.005) as well as the median concentrations of anaerobic bacteria in the posttransplant period (P <.0001) were higher in patients contracting grades II to IV acute GVHD. Neither chronic GVHD nor overall survival was significantly different between the two study arms. In patients with HLA-identical sibling donors who were treated in early disease stages, the 5-year survival estimate was slightly, but not significant, higher after the combined decontamination medication (60% +/- 11%) compared with ciprofloxacin alone (46% +/- 9%). In conclusion, the present study provides evidence that antimicrobial chemotherapy targeted to intestinal anaerobic bacteria in marrow transplant recipients significantly reduces the severity of acute GVHD and supports the theory that the intestinal anaerobic bacterial microflora plays a role in the pathogenesis of acute GVHD after human marrow transplantation. PMID:10233878
Beelen, D W; Elmaagacli, A; Müller, K D; Hirche, H; Schaefer, U W
Ethanol toxicity on liver is a function of duration of alcoholism, amount of daily intake of alcohol and patient's nutrition. The threshold of alcohol toxicity on the liver is about 40 g of ethanol daily in men and 20-30 g in women, however liver cirrhosis develops in no more than 8-20% of patients exceeding this values. Ethanol is oxidized in the liver to acetaldehyde--a compound considerably more toxic than ethanol itself. Despite small amount of alcohol dehydrogenase (ADH) found in gastric mucosa, the metabolism of ethanol in this site may have an important hepatoprotective effect. The oxidation of ethanol is associated with a change of hepatocyte redox homeostasis, which leads to a number of metabolic disorders such as lactic acidosis, hyperlipidaemia and hyperuricaemia. Chronic ethanol consumption does not influence ADH activity, but has a profound stimulatory effect on microsomal enzymes, in particular cytochrome CYP2E1. This fact is responsible for development in alcoholic liver associated with rise of oxygen consumption, excessive production of free radicals and increased metabolism of ethanol, vitamin A and testosterone. Ethanol and acetaldehyde have a deleterious effect, both the direct and indirect, on hepatocytes e.g., generating radical oxygen species and damaging intestinal mucosal barrier. Cellular oxidative stress that is caused by both an excess of free radicals and the antioxidatives' deficiency (glutathion, vitamin E, phosphatidylcholine), may be the principal factor responsible for progression of alcoholic liver disease. Among other factors accelerating alcohol-related liver lesion there are certain drugs, high fat diet, infection with HCV and genetic factors (female sex, enzymatic polymorphic forms of ADH and ALDH, hemochromatosis). Great importance in pathogenesis of necrotic and inflammatory hepatic events is being attributed to portal endotoxaemia and cytokines induced within the liver, in particular TNF-alpha and interleukin 8. These cytokines play a key role in development of alcoholic hepatitis, which clinical severity ranges from subclinical to fatal forms. Apart from abstinence, the treatment of alcohol liver disease is based on hyperalimentation, since alcoholism is generally associated with protein malnutrition. In severe forms of alcohol hepatitis corticosteroids are recommended. PMID:12901271
Waluga, Marek; Hartleb, Marek
A prospective study was conducted to define the characteristics of ascitic fluid in alcoholic cirrhotics with and without spontaneous bacterial peritonitis (SBP); to correlate these with findings in the peripheral blood; and to determine whether the use of counterimmunoelectrophoresis (CIE) for bacterial antigens will aid in the early diagnosis of SBP. Fifty-one alcoholic cirrhotics had simultaneous determination of their blood
Joanne A. P. Wilson; Eden A. Suguitan; William A. Cassidy; Richard H. Parker; Chao H. Chan
BackgroundThe brain–gut axis is a key regulator of normal intestinal physiology; for example, psychological stress is linked to altered gut barrier function, development of food allergies and changes in behaviour. Whether intestinal events, such as enteric bacterial infections and bacterial colonisation, exert a reciprocal effect on stress-associated behaviour is not well established.ObjectiveTo determine the effects of either acute enteric infection
Mélanie G Gareau; Eytan Wine; David M Rodrigues; Joon Ho Cho; Mark T Whary; Dana J Philpott; Glenda MacQueen; Philip M Sherman
Bile salts are surface-active steroid compounds. Their main physiological function is aiding the digestion of lipophilic nutrients\\u000a in intestinal tracts of vertebrates. Many bacteria are capable of transforming and degrading bile salts in the digestive tract\\u000a and in the environment. Bacterial bile salt transformation and degradation is of high ecological relevance and also essential\\u000a for the biotechnological production of steroid
We report a case of intestinal lymphangiectasia secondary to radiotherapy and chemotherapy. The patient also had small bowel bacterial overgrowth and pancreatic insufficiency. Lymphatic ectasia as a histological feature has been described previously in association with postradiotherapy malabsorption, but radiation-induced lymphangiectasia producing clinical manifestations has hitherto not been reported. Replacement of dietary long-chain fats with medium-chain triglycerides, pancreatic enzyme supplements, and a short course of oxytetracycline, resulted in dramatic clinical improvement. The possibility of intestinal lymphangiectasia should be borne in mind in patients with postradiotherapy malabsorption. A low serum albumin and lymphocyte count should draw attention to this possibility.
Rao, S.S.; Dundas, S.; Holdsworth, C.D.
Intestinal metaplasia (IM) of the stomach is a risk factor in developing intestinal-type gastric cancer and hence the question of reversibility is vital. There is emerging epidemiological evidence that with long term follow up, IM may be reversible although a combination of antioxidant agents and eradication of H pylori may be necessary to achieve this. The pathogenesis of IM is currently being elucidated and it is likely that a combination of bacterial, host, and environmental factors will be shown to lead to IM. In assessing gastric cancer risk, histochemical typing of IM will most probably be replaced by molecular markers.
Walker, M M
Bacterial vaginosis, the most prevalent cause of vaginal discharge in the United States, is characterized microbiologically\\u000a by a shift in the vagina away from a lactobacillus-predominant flora and toward a predominantly anaerobic milieu. The cause\\u000a of bacterial vaginosis is unknown, but the epidemiology of the syndrome suggests that it is sexually associated. Bacterial\\u000a vaginosis has been associated with various complications,
Jane R. Schwebke
Recent studies have suggested that alterations in the composition of the intestinal microbiota may play an important role in irritable bowel syndrome (IBS) symptoms. However, an association between the composition of the intestinal microbiota and IBS symptoms has not been clearly demonstrated. In the current issue of the Journal, Tana et al. suggest that altered intestinal microbiota contributes to the symptoms of IBS through increased levels of organic acids. In fecal samples, IBS patients had significantly higher numbers of Veillonella and Lactobacillus than healthy controls. They also showed significantly higher levels of acetic acid and propionic acid. Furthermore, IBS patients with high acetic acid or propionic acid levels presented more severe symptoms, impaired quality of life and negative emotions. These results are in accordance with the concept that the gut microbiota influences the sensory, motor and immune system of the gut and interacts with higher brain centers. Small intestinal bacterial overgrowth observed in a subset of IBS patients describes quantitative changes in the small intestinal microbiota. Data on qualitative changes in the gut microbiota in IBS patients are lacking. Different members of gut bacteria may have different influence on gut function. The concepts identified here may lead to the development of novel therapeutic strategies for IBS using manipulation of the intestinal microbiota. PMID:20414959
Lee, K J; Tack, J
Damage to the mucosal barrier may be assessed, non-invasively by use of sugar probes, which permeate through the transcellular or paracellular (tight junction) routes. A standardised test, with analysis of a five hour urine collection has proved useful in studying the sequelae of non-steroid anti-inflammatory drug (NSAID) administration, untreated coeliac disease, and enteric infections. Choice of probe molecule is crucial and lactulose/l-rhamnose seem to be satisfactory, in contrast with polyethylene glycol. Significant correlations have been seen between permeability and plasma IgA concentrates in nephropathy, and between permeability and the passage of neutrophil chemotactic agents. The increased permeability associated with NSAID treatment may relate to the adverse effects of NSAIDs on enterocyte mitochondrial morphology and metabolism. These two factors may predispose the mucosa to permeation of bacterial chemoattractant molecules that elaborate a local inflammatory response. A similar mechanism may operate in patients with untreated Crohn's disease, who show abnormally high permeability. Remission induced by treatment with elemental diets coincides with a reduction in permeability. The period to relapse correlated with the inability of patients to maintain low permeability to sugar probes. These results suggest a mechanism for the benefits of elemental enteral nutrients in the treatment of Crohn's disease.
Alcohol drinking habits and alcoholism are partly genetically determined. Alcohol is degraded primarily by alcohol dehydrogenase (ADH) wherein genetic variation that affects the rate of alcohol degradation is found in ADH1B and ADH1C. It is biologically plausible that these variations may be associated with alcohol drinking habits and alcoholism. By genotyping 9080 white men and women from the general population,
Janne Schurmann Tolstrup; Børge Grønne Nordestgaard; Søren Rasmussen; Anne Tybjærg-Hansen; Morten Grønbæk
We evaluated phospholipase activity in the intestine of rats and other species. Phospholipase activity was assayed by a surface barostat technique or an egg yolk titration system. Mucosal activity was found only by the surface barostat technique with phosphatidylglycerol as substrate; it was not found with phosphatidylcholine as substrate in assays by either technique. In gut luminal fluid activity was found when both phosphatidylcholine and phosphatidylglycerol were used as substrate in assays by the surface barostat technique, and phosphatidylcholine as substrate yielded activity in egg yolk titration. In rats in which pancreatic juice had been diverted, mucosal and gut luminal phospholipase activity was greater than in controls, thus demonstrating that enzyme activity was not due to pancreatic phospholipase. Bacterial origin of phospholipase activity was excluded in that phospholipase activity was found in germ-free rats; gastric and salivary gland origins were excluded in that continued phospholipase activity was found in rats with gastric fistula. The physiological importance of the enzyme was established by the finding that rats with pancreatic fistula absorbed 111 ?mol of phosphatidylcholine and that controls absorbed 119 ?mol of a 135-?mol load. Activity was found to be three times greater in the distal than in the proximal intestine; in cryptal cells it was 10 times greater than in villus tip cells. 65% of the activity in the gut lumen was tightly bound to particulate matter. We propose that intestinal phospholipase may be important in gut bacterial control, in the digestion of vegetable matter (phosphatidylglycerol is a major phospholipid in both plants and bacteria), and in the digestion of phospholipids in the gut lumen.
Mansbach, Charles M.; Pieroni, Gerard; Verger, Robert
Bacterial vaginosis is the most common cause of vaginitis, affecting over 3 million women in the United States annually. Depopulation of lactobacilli from the normal vaginal flora and overgrowth of Gardnerella vaginalis and other anaerobic species are the presumed etiology. To date, no scientific evidence shows that bacterial vaginosis is a sexually transmitted disease. Malodorous vaginal discharge is the most
Eleven genera of fish and invertebrates were collected during two cruises to the Puerto Rico Trench. Seventy-nine bacterial isolates were obtained from the intestinal tracts of the animals and 59 from adjacent sediments, organic detritus, and other non-intestinal sources. Using a newly developed taxonomic scheme, a comparative taxonomic study of the 138 cultures indicated few differences in phenotypic characteristics or in generic distribution between the two groups with pseudomonads predominating from both environments. It was concluded that the animal intestinal environment, and not a unique bacterial population contained therein, may be the significant factor in allowing microbial activity in the deep sea. The role the animal intestinal tract may play in this activity is discussed.
Oliver, James D.; Smith, J. Edward
The innate immune system plays a crucial role in maintaining the integrity of the intestine and protecting the host against a vast number of potential microbial pathogens from resident and transient gut microflora. Mucosal epithelial cells and Paneth cells produce a variety of antimicrobial peptides (defensins, cathelicidins, crytdinrelated sequence peptides, bactericidal/permeabilityincreasing protein, chemokine CCL20) and bacteriolytic enzymes (lysozyme, group IIA phospholipase A2) that protect mucosal surfaces and crypts containing intestinal stem cells against invading microbes. Many of the intestinal antimicrobial molecules have additional roles of attracting leukocytes, alarming the adaptive immune system or neutralizing proinflammatory bacterial molecules. Dysfunction of components of the innate immune system has recently been implicated in chronic inflammatory bowel diseases such as Crohn's disease and ulcerative colitis, illustrating the pivotal role of innate immunity in maintaining the delicate balance between immune tolerance and immune response in the gut. PMID:15971105
Müller, C A; Autenrieth, I B; Peschel, A
Steatorrhoea in rats with an intestinal cul-de-sac is mainly due to malabsorption of alimentary fats but faecal lipids of endogenous origin are also increased. Steatorrhoea depends on the site of the blind loop in the small intestine and is mainly caused by bacterial proliferation in the lumen of the gut. The aetiological role of Gram-positive anaerobic microbes, especially Clostridium welchii,
P. P. Hoet; H. Eyssen
Enteric microbiota play a variety of roles in intestinal health and disease. While bacteria in the intestine have been broadly characterized, little is known about the abundance or diversity of enteric fungi. This study utilized a culture-independent method termed oligonucleotide fingerprinting of rRNA genes (OFRG) to de- scribe the compositions of fungal and bacterial rRNA genes from small and large
Alexandra J Scupham; Laura L. Presley; Bo Wei; Elizabeth Bent; Natasha Griffith; Michael McPherson; Feilin Zhu; O. Oluwadara; N. Rao; J. Braun; J. Borneman
Human body has developed a holistic defence system, which mission is either to recognize and destroy the aggressive invaders or to evolve mechanisms permitting to minimize or restore the consequences of harmful actions. The host immune system keeps the capital role to preserve the microbial intestinal balance via the barrier effect. Specifically, pathogenic invaders such as, bacteria, parasites, viruses and other xenobiotic invaders are rejected out of the body via barriers formed by the skin, mucosa and intestinal flora. In case physical barriers are breached, the immune system with its many components comes into action in order to fence infection. The intestine itself is considered as an "active organ" due to its abundant bacterial flora and to its large metabolic activity. The variation among different species or even among different strains within a species reflects the complexity of the genetic polymorphism which regulates the immune system functions. Additionally factors such as, gender, particular habits, smoking, alcohol consumption, diet, religion, age, gender, precedent infections and vaccinations must be involved. Hormonal profile and stress seems to be associated to the integrity microbiota and inducing immune system alterations. Which bacterial species are needed for inducing a proper barrier effect is not known, but it is generally accepted that this barrier function can be strongly supported by providing benefic alimentary supplements called functional foods. In this vein it is stressed the fact that early intestinal colonization with organisms such as Lactobacilli and Bifidobacteria and possibly subsequent protection from many different types of diseases. Moreover, this benefic microflora dominated but Bifidobacteria and Lactobacilli support the concept of their ability to modify the gut microbiota by reducing the risk of cancer following their capacity to decrease ?-glucoronidase and carcinogen levels. Because of their beneficial roles in the human gastrointestinal tract, LAB are referred to as "probiotics", and efforts are underway to employ them in modern nutrition habits with so-called functional foods. Members of Lactobacillus and Bifidobacterium genera are normal residents of the microbiota in the human gastrointestinal tract, in which they developed soon after birth. But, whether such probiotic strains derived from the human gut should be commercially employed in the so-called functional foods is a matter of debate between scientists and the industrial world. Within a few hours from birth the newborn develops its normal bacterial flora. Indeed human milk frequently contains low amounts of non-pathogenic bacteria like Streptococcus, Micrococcus, Lactobacillus, Staphylococcus, Corynebacterium and Bifidobacterium. In general, bacteria start to appear in feces within a few hours after birth. Colonization by Bifidobacterium occurs generally within 4 days of life. Claims have been made for positive effects of Bifidobacterium on infant growth and health. The effect of certain bacteria having a benefic action on the intestinal ecosystem is largely discussed during the last years by many authors. Bifidobacterium is reported to be a probiotic bacterium, exercising a beneficial effect on the intestinal flora. An antagonism has been reported between B. bifidum and C. perfringens in the intestine of newborns delivered by cesarean section. The aim of the probiotic approach is to repair the deficiencies in the gut flora and restore the protective effect. However, the possible ways in which the gut microbiota is being influenced by probiotics is yet unknown. PMID:21515397
Bezirtzoglou, Eugenia; Stavropoulou, Elisabeth
The purpose of this study was to determine if a single dose of radiation to the rat abdomen leads to bacterial translocation into the mesenteric lymph nodes (MLN). A second issue addressed was whether translocation correlates with anatomic damage to the mucosa. The radiated group (1100 cGy) which received anesthesia also was compared with a control group and a third group which received anesthesia alone but no abdominal radiation. Abdominal radiation lead to 100% positive cultures of MLN between 12 hr and 4 days postradiation. Bacterial translocation was almost nonexistent in the control and anesthesia group. Signs of inflammation and ulceration of the intestinal mucosa were not seen until Day 3 postradiation. Mucosal damage was maximal by Day 4. Bacterial translocation onto the MLN after a single dose of abdominal radiation was not apparently dependent on anatomical, histologic damage of the mucosa.
Guzman-Stein, G.; Bonsack, M.; Liberty, J.; Delaney, J.P.
Vibrio cholerae is a strict human pathogen that causes the disease cholera. It is an old-world pathogen that has re-emerged as a new threat since the early 1990s. V. cholerae colonizes the upper, small intestine where it produces a toxin that leads to watery diarrhea, characterizing the disease . The dynamics of colonization by the bacteria of the intestines are largely unknown. Although a large initial infectious dose is required for infection, data suggests that only a smaller sub-population colonizes a portion of the small bowel leading to disease. There are many barriers to colonization in the intestines including peristalsis, fluid wash-out, viscosity of the mucus layer, and pH. We are interested in identifying the mechanisms that allow this sub-population of bacteria to survive and colonize the intestines when faced with these barriers. To elaborate the dynamics of V. cholerae infection, we have developed a mathematical model based on a convection-diffusion-reaction-swimming equation capturing bacterial dynamics coupled with Stokes equations governing fluid velocity where we developed a novel non-local boundary condition. Our results indicate that both host and bacterial factors contribute to bacterial density in the gut. Host factors include intestinal diffusion and convection rates while bacterial factors include adherence, motility and growth rates. This model can ultimately be used to test therapeutic strategies against V. cholerae.
Spagnuolo, Anna Maria; DiRita, Victor; Kirschner, Denise
The endoderm gives rise to the lining of the esophagus, stomach and intestines, as well as associated organs. To generate a functional intestine, a series of highly orchestrated developmental processes must occur. In this review, we attempt to cover major events during intestinal development from gastrulation to birth, including endoderm formation, gut tube growth and patterning, intestinal morphogenesis, epithelial reorganization, villus emergence as well as proliferation and cytodifferentiation. Our discussion includes morphological and anatomical changes during intestinal development as well as molecular mechanisms regulating these processes.
Spence, Jason R.; Lauf, Ryan; Shroyer, Noah F.
The mammalian gastrointestinal tract harbors thousands of bacterial species that include symbionts as well as potential pathogens. The immune responses that limit access of these bacteria to underlying tissue remain poorly defined. Here we show that ?? intraepithelial lymphocytes (?? IEL) of the small intestine produce innate antimicrobial factors in response to resident bacterial “pathobionts” that penetrate the intestinal epithelium. ?? IEL activation was dependent on epithelial cell-intrinsic MyD88, suggesting that epithelial cells supply microbe-dependent cues to ?? IEL. Finally, ?? T cells protect against invasion of intestinal tissues by resident bacteria specifically during the first few hours after bacterial encounter, indicating that ?? IEL occupy a unique temporal niche among intestinal immune defenses. Thus, ?? IEL detect the presence of invading bacteria through cross-talk with neighboring epithelial cells and are an essential component of the hierarchy of immune defenses that maintain homeostasis with the intestinal microbiota.
Ismail, Anisa S.; Severson, Kari M.; Vaishnava, Shipra; Behrendt, Cassie L.; Yu, Xiaofei; Benjamin, Jamaal L.; Ruhn, Kelly A.; Hou, Baidong; DeFranco, Anthony L.; Yarovinsky, Felix; Hooper, Lora V.
Traditional methods of data analysis in alcohol studies focus only on alcohol consumption as dependent variables rather than considering a global, person-in-environment perspective. The purpose of this study was to evaluate treatment outcome in a clinical trial using dimensions of life functioning in addition to quantity-frequency measures of alcohol use. Subjects were male veterans suffering from high levels of anxiety
Angelica K. Thevos; Janice M. Brown; Robert Malcolm; Carrie L Randall
Opinion statement Initial empiric therapy for community-acquired bacterial meningitis should be based on the possibility that penicillin-resistant\\u000a pneumococci may be the etiologic organisms and, hence, should include a combination of third-generation cephalosporin (cefotaxime\\u000a or ceftriaxone) and vancomycin. Ampicillin should be included if the patient has predisposing factors that are associated\\u000a with a risk for infection with Listeria monocytogenes. Bacterial isolates from
Karen L. Roos
Urinary tract infection is one of the most common health problems affecting patients of all ages. It is the most common nosocomial\\u000a bacterial infection in the elderly. Women are especially prone to urinary tract infections (UTIs). Although prostatitis syndrome\\u000a accounts for 25% of male office visits for genitourinary tract infections, only 5% are attributed to a bacterial cause. Acute\\u000a cystitis
Joseph B. Abdelmalak; Jeannette M. Potts
Summary. Background: Alcohol consumption by pregnant animals and humans leads to general growth impairment in their offspring, delayed growth and multiple birth defects collectively called “Fetal Alcohol Syndrome”. In utero exposure of ethanol to rat pups causes damage to their developing intestinal epithelium which leads to impairment of nutrient assimilation and growth retardation during postnatal development. Aim: To determine the
Sonali Bhalla; Safrun Mahmood; Akhtar Mahmood
Objectives. The pain intensity of patients with FM has recently been reported to be correlated with the degree of small intestinal bacterial overgrowth (SIBO). SIBO is often associated with an increased intestinal permeability (IP). Increased IP, if shown in FM, may have pathogenetic relevance because it leads to the exposure of immune cells to luminal antigens and consequent immune modulation.
A. Goebel; S. Buhner; R. Schedel; H. Lochs; G. Sprotte
To determine whether ingestion of yogurt would alter human intestinal bacterial composition and whether Bi- fidobacterium numbers would increase in the intestine, 34 healthy volunteers were studied. The experimental period was 26 d, including an initial 8 d without yogurt, 10 d with three bottles (230 ml each) of AB yogurt per day (President Enterprise Corporation, Tainan, Tai- wan), and
R. M. Chen; J. J. Wu; S. C. Lee; A. H. Huang; H. M. Wu
Background\\/Aims: Infections cause a major clinical problem within the first days after cerebral stroke. In a mouse model we have recently demonstrated that stroke leads to immunodepression facilitating spontaneous bacterial pneumonia and bacteremia. So far, it has been unknown whether poststroke immunomodulation impairs local intestinal immune populations which may promote gut barrier dysfunction leading to translocation of intestinal microorganisms and
Olaf Schulte-Herbrüggen; David Quarcoo; Andreas Meisel; Christian Meisel
Objective: Measurements of hydrogen (H2) and nitric oxide (NO) levels in intestinal gas have recently been shown to be useful to monitor bacterial colonization in healthy term newborn infants. The significance of preterm birth and antibiotic therapy for intestinal gas production is not known and was the subject of this study. Methods: A minimally invasive tonometric technique was used for
Tanja Sobko; Kristina Elfström; Lars Navér; Jon O. Lundberg; Mikael Norman
One out of 2 Americans report drinking on a routine basis, making the excessive consumption of alcohol the third leading cause of preventable death in America (). Alcoholism and depression are common comorbidities that home healthcare professionals frequently encounter. To achieve the best patient outcomes, alcoholism should be addressed initially. Although all age groups are at risk, alcoholism and depression occur in more than 8 percent of older adults. Prevention through identifying alcohol use early in adolescence is vital to reduce the likelihood of alcohol dependence. This article provides an overview of the long-term effects of alcohol abuse, including alcoholic cirrhosis and hepatic encephalopathy. The diagnostic criteria for substance dependence and ideas for nonthreatening screening questions to use with patients who are adolescent or older are discussed. While providing patient care, home healthcare nurses share the patient's intimate home environment. This environment is perceived as a safe haven by the patient and home care nurses can take advantage of counseling and treatment opportunities in this nonthreatening environment. PMID:23026991
... acid/base balance and oxygen level in blood) Blood alcohol level Blood chemistries, such as CHEM-20 Toxicology (poison) screening ... a vein. You may need to have your blood taken often. You may get ... excess alcohol use. People with this condition are admitted to ...
The motility of organisms is often directed in response to environmental stimuli. Rheotaxis is the directed movement resulting from fluid velocity gradients, long studied in fish, aquatic invertebrates, and spermatozoa. Using carefully controlled microfluidic flows, we show that rheotaxis also occurs in bacteria. Excellent quantitative agreement between experiments with Bacillus subtilis and a mathematical model reveals that bacterial rheotaxis is a purely physical phenomenon, in contrast to fish rheotaxis but in the same way as sperm rheotaxis. This previously unrecognized bacterial taxis results from a subtle interplay between velocity gradients and the helical shape of flagella, which together generate a torque that alters a bacterium's swimming direction. Because this torque is independent of the presence of a nearby surface, bacterial rheotaxis is not limited to the immediate neighborhood of liquid–solid interfaces, but also takes place in the bulk fluid. We predict that rheotaxis occurs in a wide range of bacterial habitats, from the natural environment to the human body, and can interfere with chemotaxis, suggesting that the fitness benefit conferred by bacterial motility may be sharply reduced in some hydrodynamic conditions.
Marcos; Fu, Henry C.; Powers, Thomas R.; Stocker, Roman
Preparing an aldehyde from an alcohol by contacting the alcohol in the presence of oxygen with a catalyst prepared by contacting an intimate mixture containing metal oxide support particles and particles of a catalytically active metal oxide from Groups VA, VIA, or VIIA, with a gaseous stream containing an alcohol to cause metal oxide from the discrete catalytically active metal oxide particles to migrate to the metal oxide support particles and to form a monolayer of catalytically active metal oxide on said metal oxide support particles.
Wachs, Israel E. (Bridgewater, NJ); Cai, Yeping (Louisville, KY)
The succession of gastrointestinal flora in the developing rat was studied, concomitant with studies of intestinal enzyme activity. Aerobes and anaerobes were identified as members of 4 major bacterial groups, i.e., Lactobacilli spp., Gram positive enterococci, Gram negative rods...
The intestinal mucosa has to withstand exposure to a variety of substances, challenges in pH, temperature, and osmolarity; and, finally, bacterial products which might induce local and systemic inflammatory responses. The mucosal integrity is conserved by a defense system which consisting of constitutive and inducible mechanisms. These include the physical barrier function; the secretion of factors into the lumen, such
Jan-Michel Otte; Karlheinz Kiehne; Karl-Heinz Herzig
The healthy swine intestine is populated by upwards of 500 bacterial species, mainly obligate anaerobes. Our research focuses on the roles of these commensal bacteria in antimicrobial resistance and on interventions to reduce the prevalence of antibiotic resistant bacteria. In comparisons of intes...
SUMMARY Regulation of intestinal dietary fat absorption is critical to maintaining energy balance. While intestinal microbiota clearly impact the host’s energy balance, their role in intestinal absorption and extra-intestinal metabolism of dietary fat is less clear. Using in vivo imaging of fluorescent fatty acid (FA) analogs delivered to gnotobiotic zebrafish hosts, we reveal that microbiota stimulate FA uptake and lipid droplet (LD) formation in the intestinal epithelium and liver. Microbiota increase epithelial LD number in a diet-dependent manner. The presence of food led to the intestinal enrichment of bacteria from the phylum Firmicutes. Diet-enriched Firmicutes and their products were sufficient to increase epithelial LD number, whereas LD size was increased by other bacterial types. Thus, different members of the intestinal microbiota promote FA absorption via distinct mechanisms. Diet-induced alterations in microbiota composition might influence fat absorption, providing mechanistic insight into how microbiota-diet interactions regulate host energy balance.
Semova, Ivana; Carten, Juliana D.; Stombaugh, Jesse; Mackey, Lantz C.; Knight, Rob; Farber, Steven A.; Rawls, John F.
Bacterial vaginosis is a common cause of abnormal discharge in women of child-bearing age. It is present in 10–20% women in the UK, and may recur or regress spontaneously. It is not regarded as an STI because it can occur in virgin women, but it is more common in sexually active women. Other associations include smoking, partner change, having a
Many bacteria and fungi can enhance plant growth. The present review is limited to plant growth promoting rhizobacteria (PGPR). However, it includes endophytic bacteria that show plant growth enhancing activity as well. Also the best studied bacterial mechanisms of plant growth promotion are discussed, with a special emphasis on biological nitrogen fixation and synthesis of phytohormones, including less understood mechanisms
LUIS E. FUENTES-RAMIREZ; Jesus Caballero-Mellado
Background Cystic fibrosis (CF) is caused by mutations in the CFTR gene that impair the function of CFTR, a cAMP-regulated anion channel. In the small intestine loss of CFTR function creates a dehydrated, acidic luminal environment which is believed to cause an accumulation of mucus, a phenotype characteristic of CF. CF mice have small intestinal bacterial overgrowth, an altered innate immune response, and impaired intestinal transit. We investigated whether lubiprostone, which can activate the CLC2 Cl- channel, would improve the intestinal phenotype in CF mice. Methods Cftrtm1UNC (CF) and wildtype (WT) littermate mice on the C57BL/6J background were used. Lubiprostone (10 ?g/kg-day) was administered by gavage for two weeks. Mucus accumulation was estimated from crypt lumen widths in periodic acid-Schiff base, Alcian blue stained sections. Luminal bacterial load was measured by qPCR for the bacterial 16S gene. Gastric emptying and small intestinal transit in fasted mice were assessed using gavaged rhodamine dextran. Gene expression was evaluated by Affymetrix Mouse430 2.0 microarray and qRT-PCR. Results Crypt width in control CF mice was 700% that of WT mice (P < 0.001). Lubiprostone did not affect WT crypt width but, unexpectedly, increased CF crypt width 22% (P = 0.001). Lubiprostone increased bacterial load in WT mice to 490% of WT control levels (P = 0.008). Conversely, lubiprostone decreased bacterial overgrowth in CF mice by 60% (P = 0.005). Lubiprostone increased gastric emptying at 20 min postgavage in both WT (P < 0.001) and CF mice (P < 0.001). Lubiprostone enhanced small intestinal transit in WT mice (P = 0.024) but not in CF mice (P = 0.377). Among other innate immune markers, expression of mast cell genes was elevated 4-to 40-fold in the CF intestine as compared to WT, and lubiprostone treatment of CF mice decreased expression to WT control levels. Conclusions These results indicate that lubiprostone has some benefits for the CF intestinal phenotype, especially on bacterial overgrowth and the innate immune response. The unexpected observation of increased mucus accumulation in the crypts of lubiprostone-treated CF mice suggests the possibility that lubiprostone increases mucus secretion.
A quantitative assay based on high-performance liquid chromatography analysis of bile salts and bacterial protein determination was established for investigating bile salt hydrolase (BSH) activity in bacteria isolated from the small intestine of chickens. Bacteria were isolated using various media and were subsequently grouped according to cell morphology, fermentation profile, and 16S ribosomal DNA sequence. Representative isolates from each bacterial
Ane Knarreborg; Ricarda M. Engberg; Søren K. Jensen; Bent B. Jensen
Gut microbiota carry out key functions in health and participate in the pathogenesis of a growing number of diseases. The aim of this study was to develop a custom microarray that is able to identify hundreds of intestinal bacterial species. We used the Entrez nucleotide database to compile a data set of bacterial 16S rRNA gene sequences isolated from human
Oleg Paliy; Harshavardhan Kenche; Frank Abernathy; Sonia Michail
Background: Although bacterial infections are frequent in patients with liver cirrhosis, only isolated cases of bacterial meningitis have been reported.Methods: We have reviewed a series of 16 cases of bacterial meningitis in patients with cirrhosis, diagnosed in a single hospital over a 30-year period.Results: Thirteen patients had alcoholic cirrhosis. On presentation, all patients had fever and most of them had
Arnaud Pauwels; Emmanuelle Pinès; Maamar Abboura; Isabelle Chiche; Victor-Georges Lévy
Recent studies have revealed that bacteria target stem cells for long-term survival in a Drosophila model. However, in mammalian models, little is known about bacterial infection and intestinal stem cells. Our study aims at understanding bacterial regulation of the intestinal stem cell in a Salmonella colitis mouse model. We found that Salmonella activates the Wnt/?-catenin signaling pathway that is known to regulate stem cells. We identified Salmonella protein AvrA that modulates Wnt signaling including upregulating Wnt expression, modifying ?-catenin, increasing total ?-catenin expression, and activating Wnt/?-catenin transcriptional activity in the intestinal epithelial cells. The numbers of stem cells and proliferative cells increased in the intestine infected with Salmonella expressing AvrA. Our study provides insights into bacterial infection and stem cell maintenance.
Liu, Xingyin; Lu, Rong; Wu, Shaoping; Sun, Jun
Intestinal condition and ethanol toxicity have been discussed as predictors of alcoholic liver damage. In this study, we investigated the association of hepatic antioxidant enzymes and cecal condition, including intestinal bac- teria estimated by terminal restriction fragment length polymorphism (T-RFLP), in the early stage of alcoholic fatty liver. Three liquid isocaloric diets, control (CT) diet, ethanol (ET) diet, or ethanol
Naoto Hashimoto; Hiroyuki Sekiguchi; Akira Masunaka; Katsuichi Saito; Hiroaki Yamauchi; Takahiro Noda; Kyu-Ho Han; Michihiro Fukushima
Rheotaxis is the directed movement of an organism resulting from fluid velocity gradients, long studied in fish, aquatic invertebrates and spermatozoa. Here we show that rheotaxis also occurs in bacteria. Using controlled microfluidic shear flows, we demonstrate and quantify rheotaxis in Bacillus subtilis. A mathematical model of a bacterium swimming in a shear flow is in good agreement with observations and reveals that bacterial rheotaxis results from a subtle interplay between velocity gradients and the helical shape of flagella, which together generate a torque that reorients the cell, altering its swimming direction. The magnitude of the observed rheotactic velocity is comparable to typical chemotactic velocities, suggesting that rheotaxis can interfere with bacterial processes based on directed motility, such as foraging and infection.
Marcos, Marcos; Fu, Henry; Powers, Thomas; Stocker, Roman
Patients with short bowel syndrome require long term parenteral nutrition support. However, after massive intestinal resection the intestine undergoes adaptation and nutritional autonomy may be obtained. Given that the complications of parenteral nutrition may be life threatening or result in treatment failure and the need for intestinal transplantation, a more attractive option is to wean patients off nutrition support by optimising the adaptive process. The article examines the evidence that after extensive small bowel resection adaptation occurs in humans and focuses on the factors that influence adaptation and the strategies that have been used to optimise this process. The review is based on an English language Medline search with secondary references obtained from key articles. There is evidence that adaptation occurs in humans. Adaptation is a complex process that results in response to nutrient and non-nutrient stimuli. Successful and reproducible strategies to improve adaptation remain elusive despite an abundance of experimental data. Nevertheless given the low patient survival and quality of life associated with other treatments for irreversible intestinal failure it is imperative that clinical research continues into the optimisation of the adaptation.
Weale, A; Edwards, A; Bailey, M; Lear, P
Bile salts are surface-active steroid compounds. Their main physiological function is aiding the digestion of lipophilic nutrients in intestinal tracts of vertebrates. Many bacteria are capable of transforming and degrading bile salts in the digestive tract and in the environment. Bacterial bile salt transformation and degradation is of high ecological relevance and also essential for the biotechnological production of steroid drugs. While biotechnological aspects have been reviewed many times, the physiological, biochemical and genetic aspects of bacterial bile salt transformation have been neglected. This review provides an overview of the reaction sequence of bile salt degradation and on the respective enzymes and genes exemplified with the degradation pathway of the bile salt cholate. The physiological adaptations for coping with the toxic effects of bile salts, recent biotechnological applications and ecological aspects of bacterial bile salt metabolism are also addressed. As the pathway for bile salt degradation merges with metabolic pathways for bacterial transformation of other steroids, such as testosterone and cholesterol, this review provides helpful background information for metabolic engineering of steroid-transforming bacteria in general. PMID:21088832
Two cases of colonic gas explosion during surgery are reported. The treatment of the lesions required a partial colectomy in one case and a total colectomy in the other case. The different factors involved in such accidents are discussed. Three factors are necessary to trigger off an explosion of intestinal gases: the presence of combustible gases (hydrogen, methane), the presence of combustive gases (oxygen, nitrous oxide) and an initiating heat source (endoscopic or surgical electrocautery). The mannitol used for bowel cleansing undergoes partial colonic bacterial fermentation increasing the intraluminal concentration of hydrogen. During anaesthesia the oxygen-nitrous oxide mixture increases the intestinal concentration of these two major combustive gases. Electrocautery provides the spark triggering the explosion. The use of mannitol for colonic preparation should be questioned; the use of electrocautery to open the colon is advised against. PMID:6419649
Bonnet, Y Y; Haberer, J P; Schutz, R; Simon, R; Vanwynsberghe, B; Mercier, R
The results of treatment of 262 patients with gunshot wounds of the large intestine are described. 207 (79%) patients had colic injuries and the rest 55 (21%) - gunshot wounds of the rectum. Authors adduce and substantiate the differential approach to each case, taking into consideration various factors, such as localization, size of the wound, grade of bacterial contamination and peritonitis etc In case of an injured colic segment resection necessity, obstructive resection was preferred. In case of intraperitoneal rectum injury wound closure with decompressive sigmostomy was justified. Extraperitoneal rectum injury requires surgical debridement without intestinal wall reconstruction and further sphincteroplasty. Postoperative lethality was 26,6% for colic injuries and 34,5% for rectal injuries. 85 patients experienced further reconstructive operations. PMID:19156070
Aliev, S A; Salakhov, Z A
Inflammasomes are multi-protein complexes that mediate activation of caspase-1, which promotes secretion of the proinflammatory cytokines interleukin (IL)-1? and IL-18 and pyroptosis, a form of phagocyte cell death induced by bacterial pathogens. Members of the Nod-like receptor family (including Nlrp1, Nlrp3, and Nlrc4), the DNA sensor Aim2, the adaptor ASC, and pro-caspase-1 are important components of inflammasomes. Stimulation with specific microbial and endogenous molecules leads to inflammasome assembly and caspase-1 activation. Inflammasomes are believed to mediate host defense against microbial pathogens and tissue homeostasis within the intestine, and their dysregulation might contribute to inflammatory diseases and intestinal cancer. Improving our understanding of inflammasome signaling pathways could provide insights into pathogenesis of many gastrointestinal disorders and the development of therapeutics targets and approaches to treat diseases such as inflammatory bowel diseases and GI cancers.
Chen, Grace Y.; Nunez, Gabriel
Rodent models harboring a simple yet functional human intestinal microbiota provide a valuable tool to study the relationships between mammals and their bacterial inhabitants. In this study, we aimed to develop a simplified gnotobiotic mouse model containing 10 easy-to-grow bacteria, readily available from culture repositories, and of known genome sequence, that overall reflect the dominant commensal bacterial makeup found in adult human feces. We observed that merely inoculating a mix of fresh bacterial cultures into ex-germ free mice did not guarantee a successful intestinal colonization of the entire bacterial set, as mice inoculated simultaneously with all strains only harbored 3 after 21 d. Therefore, several inoculation procedures were tested and levels of individual strains were quantified using molecular tools. Best results were obtained by inoculating single bacterial strains into individual animals followed by an interval of two weeks before allowing the animals to socialize to exchange their commensal microbes. Through this procedure, animals were colonized with almost the complete bacterial set (9/10). Differences in the intestinal composition were also reflected in the urine and plasma metabolic profiles, where changes in lipids, SCFA, and amino acids were observed. We conclude that adaptation of bacterial strains to the host’s gut environment (mono-colonization) may predict a successful establishment of a more complex microbiota in rodents.
Rezzonico, Enea; Mestdagh, Renaud; Delley, Michele; Combremont, Severine; Dumas, Marc-Emmanuel; Holmes, Elaine; Nicholson, Jeremy; Bibiloni, Rodrigo
Alcohol intoxication is the principal drug addiction in many countries of the world. It affects all age groups, both sexes and almost all social groups. Mortality associated with acute alcohol poisoning on its own is exceptional, but it can be an important factor if it coexists with recreational drugs. It is directly responsible for more than half of traffic accidents. Diagnosis is easy by means of anamnesis and clinical examination, and can be confirmed by determining the level of ethanol in the bloodstream. Supportive care is the best therapy in order to protect the patient from secondary complications. Methanol, or alcohol fuel, is used as a solvent, and can also be found as an adulterant of alcoholic drinks. Poisoning by oral means is the most frequent. Oxidized in the liver through dehydrogenase enzyme alcohol, toxicity is due to its metabolites, formaldehyde and formic acid. The clinical picture basically consists of cephalea, nausea, vomiting, hypotension and depression of the central nervous system. The optic nerve is especially sensitive, with total and irreversible blindness as a possible result. Ethylenglicol is used as a solvent and as an antifreeze; toxicity is due to an accumulation of its metabolites. The clinical picture includes symptoms that are held in common with methylalcohol intoxication. Kidney failure due to tubular necrosis and the deposit of oxalate crystals can occur. PMID:12813481
Roldán, J; Frauca, C; Dueñas, A
According to the World Health Organization, alcohol is the third most dangerous factor following smoking of tobacco and hypertension of risks impacting health of the population. 50 % of men and 10 % of women suffer from diseases caused by alcohol drinking. Chronic consumption of alcohol damages the nervous system, causes adverse changes in the circulatory system and intestine, increases the risk of cancers. Comparing the impact of alcohol on the health of women and men, in case of women, even similar levels of consumption cause stronger action. Alcohol is the cause of endocrine diseases and among others- reduces fertility. It is the risk factor of premature deliveries, abortions, and placenta- associated pathologies. Disorders of children with prenatal exposure to alcohol are described as fetal alcohol syndrome, alcohol related neurodevelopmental disorders and alcohol related birth defects. It is recommended to impose a total ban on alcohol consumption by pregnant women. Moreover one should emphasize that the minimum safe dose of alcohol for the foetus cannot be specified. In order to resolve alcohol drinking problems a cooperation of representatives of many professions such as: doctors, psychologists, educators and employees of care facilities is necessary. It is also obligatory to obtain support and assistance from the nearest surroundings of the patient. PMID:23421101
Jagielska, Iwona; Kazdepka-Ziemi?ska, Anita; Stankiewicz, Martyna; Ka?mierczak, Jolanta
... risk for alcohol dependence. This Alert explores the relationship between alcohol and stress, including identifying some common sources ... should help researchers to further define the complex relationship between stress and alcohol. 26 References 1 Keyes, K. ...
The aggregation substance of Enterococcus faecalis increased bacterial adherence to and internalization by epithelial cells originating from the colon and duodenum but not by cells derived from the ileum. However, enterococcal translocation through monolayers of intestinal epithelium was not observed.
Sartingen, S.; Rozdzinski, E.; Muscholl-Silberhorn, A.; Marre, R.
The possible occurrence of metabolic acidosis in patients with intestinal ileus is not well recognized. We describe a patient with acute alcohol-induced pancreatitis and a large transverse colon ileus in which plasma bicarbonate dropped rapidly in the absence of an increase in the plasma anion gap. The urinary anion gap and ammonium excretion were consistent with an appropriate renal response to metabolic acidosis and against the possibility of respiratory alkalosis. The cause of the falling plasma bicarbonate was ascribed to intestinal bicarbonate sequestration owing to the enhancement of chloride-bicarbonate exchange in a dilated paralyzed colon. PMID:17334600
Serrano, Andres; Chilakapati, Rajani K; Ghanayem, Alexander J; Yuan, Yemin; Alberts, Jeffery; Stephen, Cathy; Rombola, Giuseppe; Batlle, Daniel
Keeping mammalian gastrointestinal (GI) tract communities in balance is crucial for host health maintenance. However, our understanding of microbial communities in the GI tract is still very limited. In this study, samples taken from the GI tracts of C57BL/6 mice were subjected to 16S rRNA gene sequence-based analysis to examine the characteristic bacterial communities along the mouse GI tract, including those present in the stomach, duodenum, jejunum, ileum, cecum, colon and feces. Further analyses of the 283,234 valid sequences obtained from pyrosequencing revealed that the gastric, duodenal, large intestinal and fecal samples had higher phylogenetic diversity than the jejunum and ileum samples did. The microbial communities found in the small intestine and stomach were different from those seen in the large intestine and fecal samples. A greater proportion of Lactobacillaceae were found in the stomach and small intestine, while a larger proportion of anaerobes such as Bacteroidaceae, Prevotellaceae, Rikenellaceae, Lachnospiraceae, and Ruminococcaceae were found in the large intestine and feces. In addition, inter-mouse variations of microbiota were observed between the large intestinal and fecal samples, which were much smaller than those between the gastric and small intestinal samples. As far as we can ascertain, ours is the first study to systematically characterize bacterial communities from the GI tracts of C57BL/6 mice.
Gu, Shenghua; Chen, Dandan; Zhang, Jin-Na; Lv, Xiaoman; Wang, Kun; Duan, Li-Ping; Nie, Yong; Wu, Xiao-Lei
Dr. Brett Finlay shows how bacteria can grow rapidly to incredible numbers, and also explains what limits this explosive growth. This resource would be great preparation material for a classroom discussion or video presentation for both the students and the teacher. This visual helps further broaden the knowledge of students in both the upper high school and college undergraduate on bacterial growth. The lecture is featured on the DVD 2000 and Beyond: Confronting the Microbe Menace, available free from HHMI. The video is 54 seconds long and available on WMV (10MB) and MOV (8MB). All Infection Disease videos can be found at http://www.hhmi.org/biointeractive/disease/video.html .
Howard Hughes Medical Institute (;)
Intestinal failure is a condition characterized by malnutrition and/or dehydration as a result of the inadequate digestion and absorption of nutrients. The most common cause of intestinal failure is short bowel syndrome, which occurs when the functional gut mass is reduced below the level necessary for adequate nutrient and water absorption. This condition may be congenital, or may be acquired as a result of a massive resection of the small bowel. Following resection, the intestine is capable of adaptation in response to enteral nutrients as well as other trophic stimuli. Identifying factors that may enhance the process of intestinal adaptation is an exciting area of research with important potential clinical applications. PMID:16937429
Drozdowski, Laurie; Thomson, Alan B R
Two male full-term infants presented with unusual features of lactobezoar. One had gastric disease while the other had small bowel bezoar. The gastric lactobezoar was managed medically while the intestinal one required surgical intervention. PMID:11400808
Rao PVH; Raveenthiran, V; Dhanalakshmi, M
Self-renewal in the intestinal epithelia is fueled by a population of undifferentiated intestinal stem cells (ISCs) that give rise to daughter or progenitor cells, which can subsequently differentiate into the mature cell types required for normal gut function. The cellular signals that regulate self-renewal are poorly understood and the factors that mediate the transition from a stem cell to a progenitor cell in the gut are unknown. Recent studies have suggested that ISCs are located either at the crypt base interspersed between the Paneth cells (eg, Lgr-5+ve cells) or at or near position 4 within the intestinal crypt (eg, DCAMKL-1 or Bmi-1+ve cells). This raises the possibility that distinct stem cell regions exist in the crypts and that ISC's state of activation will determine how the self-renewal is regulated in the intestinal tract.
|Briefly discusses some aspects of the role of the state and the position of minorities in respect to alcoholism policies and services. Includes case study of a Black alcoholic. Refers readers to studies on Black alcoholism, Native American alcoholism, Hispanic alcoholism, and Asian-American alcoholism. (Author/NB)|
Watts, Thomas D.; Wright, Roosevelt, Jr.
Alcohol is a major cause of liver cirrhosis in the Western world and accounts for the majority of cases of liver cirrhosis seen in district general hospitals in the UK. The three most widely recognised forms of alcoholic liver disease are alcoholic fatty liver (steatosis), acute alcoholic hepatitis, and alcoholic cirrhosis. The exact pathogenesis of alcoholic liver injury is still
Kevin Walsh; Graeme Alexander
Short-chain fatty acids (SCFAs), such as acetate, propionate, and butyrate, are the major anions in the large intestinal lumen. They are produced from dietary fiber by bacterial fermentation and are known to have a variety of physiological and pathophysiological effects on the intestine. In the present study, we investigated the expression of the SCFA receptor, GPR43, in the rat distal
Shin-ichiro Karaki; Retsu Mitsui; Hisayoshi Hayashi; Ikuo Kato; Hiroshi Sugiya; Toshihiko Iwanaga; John B. Furness; Atsukazu Kuwahara
The Great Western Sugar Company has announced plans for the construction of a $300 million plant for the production of fuel grade alcohol from corn. The plant at Reserve, Lousiana, will also produce high fructose corn syrup and animal feed by-products and will employ an additional 200 people.
Regulation of intestinal dietary fat absorption is critical to maintaining energy balance. While intestinal microbiota clearly impact the host's energy balance, their role in intestinal absorption and extraintestinal metabolism of dietary fat is less clear. Using in vivo imaging of fluorescent fatty acid (FA) analogs delivered to gnotobiotic zebrafish hosts, we reveal that microbiota stimulate FA uptake and lipid droplet (LD) formation in the intestinal epithelium and liver. Microbiota increase epithelial LD number in a diet-dependent manner. The presence of food led to the intestinal enrichment of bacteria from the phylum Firmicutes. Diet-enriched Firmicutes and their products were sufficient to increase epithelial LD number, whereas LD size was increased by other bacterial types. Thus, different members of the intestinal microbiota promote FA absorption via distinct mechanisms. Diet-induced alterations in microbiota composition might influence fat absorption, providing mechanistic insight into how microbiota-diet interactions regulate host energy balance. PMID:22980325
Semova, Ivana; Carten, Juliana D; Stombaugh, Jesse; Mackey, Lantz C; Knight, Rob; Farber, Steven A; Rawls, John F
Changes were examined in the intestinal microflora in broiler chickens fed a diet containing antibiotics to obtain fundamental information on the mechanisms of beneficial effect of the antibiotics upon livestock production. Three antibiotics (colistin, bacitracin, and enramycin) were employed as feed additives. Experiments were conducted with broiler chickens in two ways. In one way dietary antibiotics were fed continually at levels approved for use as feed additives for a long term. In the other they were fed the same antibiotics for a short term. Significant changes in microflora were observed mainly in such bacterial groups as aerobic bacteria and Lactobacillus. In the long term administration, three possible modes of variance in the bacterial flora were postulated: Changes directly related to the antibacterial spectrum of antibiotics. Antagonistic changes related to an ecological balance in the bacterial flora. Changes in quantitative balance of bacteria constituting each bacterial group. The change in the intestinal microflora during administration of the antibiotic diet was expressed as a complex form of these transition modes. In the short term administration, it was demonstrated that the effect of the antibiotic diet lingered even 7 days after administration. This suggests that antibiotics used as feed additives may possibly affect the stability of the intestinal microflora. PMID:6680771
Ohya, T; Sato, S
Background Patients admitted to the intensive care unit with alcohol use disorders have increased morbidity and mortality. The purpose of this study was to determine how chronic alcohol ingestion alters the host response to sepsis in mice. Methods Mice were randomized to receive either alcohol or water for 12 weeks and then subjected to cecal ligation and puncture. Mice were sacrificed 24 hours post-operatively or followed seven days for survival. Results Septic alcohol-fed mice had a significantly higher mortality than septic water-fed mice (74% vs. 41%, p?=?0.01). This was associated with worsened gut integrity in alcohol-fed mice with elevated intestinal epithelial apoptosis, decreased crypt proliferation and shortened villus length. Further, alcohol-fed mice had higher intestinal permeability with decreased ZO-1 and occludin protein expression in the intestinal tight junction. The frequency of splenic and bone marrow CD4+ T cells was similar between groups; however, splenic CD4+ T cells in septic alcohol-fed mice had a marked increase in both TNF and IFN-? production following ex vivo stimulation. Neither the frequency nor function of CD8+ T cells differed between alcohol-fed and water-fed septic mice. NK cells were decreased in both the spleen and bone marrow of alcohol-fed septic mice. Pulmonary myeloperoxidase levels and BAL levels of G-CSF and TFG-? were higher in alcohol-fed mice. Pancreatic metabolomics demonstrated increased acetate, adenosine, xanthine, acetoacetate, 3-hydroxybutyrate and betaine in alcohol-fed mice and decreased cytidine, uracil, fumarate, creatine phosphate, creatine, and choline. Serum and peritoneal cytokines were generally similar between alcohol-fed and water-fed mice, and there were no differences in bacteremia, lung wet to dry weight, or pulmonary, liver or splenic histology. Conclusions When subjected to the same septic insult, mice with chronic alcohol ingestion have increased mortality. Alterations in intestinal integrity, the host immune response, and pancreatic metabolomics may help explain this differential response.
Yoseph, Benyam P.; Breed, Elise; Overgaard, Christian E.; Ward, Christina J.; Liang, Zhe; Wagener, Maylene E.; Lexcen, Daniel R.; Lusczek, Elizabeth R.; Beilman, Greg J.; Burd, Eileen M.; Farris, Alton B.; Guidot, David M.; Koval, Michael
The authors investigated (1) the effect of morphine dependence on the migrating myoelectric complex (MMC) of the small intestine, (2) whether bacterial overgrowth developed in morphine-dependent rats, and (3) the effect of naloxone and methylbromide naltrexone, a peripheral opioid antagonist, on the MMC in morphine-naive and morphine-dependent rats. They also evaluated intestinal motility during naloxone-induced withdrawal in animals pretreated with clonidine. Intestinal myoelectric activity was monitored by four indwelling electrodes in unanesthetized, fasted rats. D-(/sup 14/C)xylose breath tests were performed before and after morphine-pellet implantation to evaluate the presence of bacterial overgrowth of the small intestine. Naloxone had no effect on myoelectric activity of the small intestine in morphine-naive rats. Cycling activity fronts were present in morphine-dependent animals, but there was a significant prolongation of activity front periodicity and slowing of the propagation velocity. No significant increase in /sup 14/CO/sub 2/ excretion was noted in the morphine-dependent rats. They conclude from their studies that (1) myoelectric activity of the small intestine develops incomplete tolerance to morphine; (2) bacterial overgrowth is not a feature of morphine dependence in the rat; (3) alterations of intestinal myoelectric activity are a component of the opiate withdrawal syndrome, and they appear at least partially mediated by a peripheral mechanism that can be suppressed by an ..cap alpha../sub 2/-adrenergic agonist.
Kuperman, D.A.; Sninsky, C.A.; Lynch, D.F.
The impact of antibiotics on the host's protective microbiota and the resulting increased susceptibility to mucosal infection are poorly understood. In this study, antibiotic regimens commonly applied to murine enteritis models are used to examine the impact of antibiotics on the intestinal microbiota, the time course of recovery of the biota, and the resulting susceptibility to enteric Salmonella infection. Molecular analysis of the microbiota showed that antibiotic treatment has an impact on the colonization of the murine gut that is site and antibiotic dependent. While combinations of antibiotics were able to eliminate culturable bacteria, none of the antibiotic treatments were effective at sterilizing the intestinal tract. Recovery of total bacterial numbers occurs within 1 week after antibiotic withdrawal, but alterations in specific bacterial groups persist for several weeks. Increased Salmonella translocation associated with antibiotic pretreatment corrects rapidly in association with the recovery of the most dominant bacterial group, which parallels the recovery of total bacterial numbers. However, susceptibility to intestinal colonization and mucosal inflammation persists when mice are infected several weeks after withdrawal of antibiotics, correlating with subtle alterations in the intestinal microbiome involving alterations of specific bacterial groups. These results show that the colonizing microbiotas are integral to mucosal host protection, that specific features of the microbiome impact different aspects of enteric Salmonella pathogenesis, and that antibiotics can have prolonged deleterious effects on intestinal colonization resistance.
Croswell, Amy; Amir, Elad; Teggatz, Paul; Barman, Melissa; Salzman, Nita H.
This is a review of literature concerning intestinal obstruction in pregnant women. Approximately 50-90% and 30% of pregnant women, respectively suffer from nausea and vomiting, mostly during the first trimester. There is also increased risk of constipation. During the perioperative period, the administration of tocolytics should be considered only in women showing symptoms of a threatening premature delivery. Intensive hydration should be ordered to sustain uterine blood flow. The incidence of intestinal obstruction during pregnancy is estimated at 1:1500-1:66431 pregnancies and is diagnosed in II and III trimester in most cases. However, it can also occur in the I trimester (6%) or puerperium. Symptoms of intestinal obstruction in pregnancy include: abdominal pains (98%), vomiting (82%), constipation (30%). Abdominal tenderness on palpation is found in 71% and abnormal peristalsis in 55% of cases. The most common imaging examination in the diagnosis of intestinal obstruction is the abdominal X-ray. However ionizing radiation may have a harmful effect on the fetus, especially during the first trimester. X-ray is positive for intestinal obstruction in 82% of pregnant women. Ultrasonography and magnetic resonance imaging are considered safe and applicable during pregnancy. Intestinal obstruction in pregnant women is mostly caused by: adhesions (54.6%), intestinal torsion (25%), colorectal carcinoma (3.7%), hernia (1.4%), appendicitis (0.5%) and others (10%). Adhesive obstruction occurs more frequently in advanced pregnancy (6% - I trimester 28% - II trimester; 45% - III trimester 21% - puerperium). Treatment should begin with conservative procedures. Surgical treatment may be necessary in cases where the pain turns from recurrent into continuous, with tachycardia, pyrexia and a positive Blumberg sign. If symptoms of fetal anoxia are observed, a C-section should be carried out before surgical intervention. The extent of surgical intervention depends on the intraoperative evaluation. Intestinal torsion during pregnancy mostly occurs in the sigmoid colon and cecum. Small bowel torsion secondary to adhesions is diagnosed in 42% of pregnant women with intestinal obstruction. The risk of intestinal torsion is higher in the 16-20 and 32-36 weeks of pregnancy and during puerperium. Intestinal torsion results in vessel occlusion which induces more severe symptoms and makes urgent surgical intervention necessary. The overall prognosis is poor--during II and III trimester the fetal mortality rate reaches 36% and 64%, respectively while the risk of maternal death is 6%. Acute intestinal pseudoobstruction can be diagnosed during puerperium, especially following a C-section. Diagnosis is made on the basis of radiological confirmation of colon distension at the cecum as > 9cm, lack of air in the sigmoid colon and rectum, exclusion of mechanical obstruction. In most cases, the treatment is based on easing intestine gas evacuation and administering neostigmine. The authors point out the need for multi-specialty cooperation in the diagnostic-therapeutic process of pregnant women suspected with intestinal obstruction, since any delay in making a correct diagnosis increases the risk of severe complications, both for the woman and the fetus. PMID:23668061
Stukan, Maciej; Kruszewski Wies?aw, Janusz; Dudziak, Miros?aw; Kopiej?, Arkadiusz; Preis, Krzysztof
... Monitoring Alcohol Use Tracking Fetal Alcohol Syndrome Preventing Alcohol Use During Pregnancy Intervention Strategies International Research Past Activities Preventing Alcohol-Exposed Pregnancies Educating ...
Enteric bacteria might act as pathogens, translocating across the intestinal barrier to extraintestinal sites after major liver resection. In the current study, water-soluble ethylhydroxyethyl cellulose (EHEC) was administered before hepatectomy to evaluate the influence on bacterial translocation induced by major liver resection, phagocytic capacity by visceral and circulating macrophages, enteric bacterial population, and bacterial adherence on the intestinal surface in rats subjected to sham operation or to 70% or 90% hepatectomy. Oral or intravenous (IV) administration of EHEC reduced the incidence of bacterial translocation to mesenteric lymph nodes (MLN) and blood after major liver resection. Oral EHEC appeared more effective than IV administration in protecting against bacterial translocation to MLN in animals with 90% hepatectomy. Ethylhydroxyethyl cellulose (oral and IV) significantly diminished intestinal macrophage uptake capacity of 125I-labeled, heat-killed Escherichia coli as compared with animals without EHEC administration. Overgrowth or colonization of enteric bacteria after major liver resection could be prevented by oral or IV EHEC. Adherence of 14C-labeled, alive E. coli on the intestinal mucosa decreased after EHEC treatment in animals subjected to major liver resection. Systemic arterial pressure and intestinal blood flow markedly decreased from 1 hour and on after 90% hepatectomy. Intravenous administration of EHEC did not improve these alterations. Bacterial hydrophobicity and surface negative charge were significantly reduced 1 hour after bacterial culture with EHEC. Thus, EHEC appears to be a potent agent preventing translocation of enteric bacteria from the gut after major liver resection, by altering the surface characters of enteric bacteria, balancing the enteric microflora, inhibiting bacterial attachment onto the intestinal surface, and blocking phagocytosis by intestinal macrophages.
Wang, X; Andersson, R; Soltesz, V; Guo, W; Bengmark, S
We have investigated the gas-phase chemistry in dense cores where ice mantles containing ethanol and other alcohols have been evaporated. Model calculations show that methanol, ethanol, propanol, and butanol drive a chemistry leading to the formation of several large ethers and esters. Of these molecules, methyl ethyl ether (CH3OC2H5) and diethyl ether [(C2H5)2O] attain the highest abundances and should be present in detectable quantities within cores rich in ethanol and methanol. Gas-phase reactions act to destroy evaporated ethanol and a low observed abundance of gas-phase C2H5OH does not rule out a high solid-phase abundance. Grain surface formation mechanisms and other possible gas-phase reactions driven by alcohols are discussed, as are observing strategies for the detection of these large interstellar molecules.
Charnley, S. B.; Kress, M. E.; Tielens, A. G. G. M.; Millar, T. J.
An immature intestinal epithelial barrier may predispose infants and children to many intestinal inflammatory diseases, such as infectious enteritis, inflammatory bowel disease, and necrotizing enterocolitis. Understanding the factors that regulate gut barrier maturation may yield insight into strategies to prevent these intestinal diseases. The claudin family of tight junction proteins plays an important role in regulating epithelial paracellular permeability. Previous reports demonstrate that rodent intestinal barrier function matures during the first 3 weeks of life. We show that murine paracellular permeability markedly decreases during postnatal maturation, with the most significant change occurring between 2 and 3 weeks. Here we report for the first time that commensal bacterial colonization induces intestinal barrier function maturation by promoting claudin 3 expression. Neonatal mice raised on antibiotics or lacking the toll-like receptor adaptor protein MyD88 exhibit impaired barrier function and decreased claudin 3 expression. Furthermore, enteral administration of either live or heat-killed preparations of the probiotic Lactobacillus rhamnosus GG accelerates intestinal barrier maturation and induces claudin 3 expression. However, live Lactobacillus rhamnosus GG increases mortality. Taken together, these results support a vital role for intestinal flora in the maturation of intestinal barrier function. Probiotics may prevent intestinal inflammatory diseases by regulating intestinal tight junction protein expression and barrier function. The use of heat-killed probiotics may provide therapeutic benefit while minimizing adverse effects. PMID:22155109
Patel, Ravi M; Myers, Loren S; Kurundkar, Ashish R; Maheshwari, Akhil; Nusrat, Asma; Lin, Patricia W
The intestinal microflora can be considered as a postnatally aquired organ composed of a large diversity of bacterial cells that can perform different functions for the host. This organ is highly exposed to environmental influences and thus modulated in its composition and functions by external factors, such as nutrition. Specific components of the intestinal microflora, including lactobacilli and bifidobacteria, have been associated with beneficial effects on the host, such as promotion of gut maturation and integrity, antagonisms against pathogens and immune modulation. In addition, the microflora seem to play a significant role in the maintenance of intestinal immune homeostasis and prevention of inflammation. At the present time, the contribution of intestinal epithlial cell in the first line of defence against pathogenic bacteria and microbial antigens has been recognized, in contrast, the interactions of intestinal epithelial cells with commensal bacteria are less understood. The present work summarizes the increasing scientific attention for mechanisms of the innate immune response of the host to different components of the autochthonous microflora and suggests a potential role for selected probiotic bacteria in the regulation of intestinal inflammation. PMID:12142966
Schiffrin, E J; Blum, S
The acid environment of the stomach serves as an important defense against intestinal colonization by potentially pathogenic bacteria. The purpose of this study was to examine the effect of increased gastric pH on bacterial translocation in a neonatal rabbit model. Fifty-nine rabbit pups were delivered by cesarean section and randomly divided into normal acid (NA) and reduced acid (RA) groups.
John E Dinsmore; Richard J Jackson; Samuel D Smith
Ultrastructural examination of biopsies showing Helicobacter pylori associated chronic gastritis reveals close attachment between gastric surface epithelial cells and the organism. The finding of 'adhesion pedestals', which represents a cellular response to the presence of the organism, is analogous to the response of intestinal cells to enteropathogenic E coli. Thus the development of bacterial attachment sites in H pylori associated
S J Hessey; J Spencer; J I Wyatt; G Sobala; B J Rathbone; A T Axon; M F Dixon
Alcohol use is one of the two main aetiologies of acute pancreatitis. Detection of excessive alcohol consumption is problematic, illustrated by the fact that self-reports of alcohol consumption account for only approximately 50% of the reported sales of alcohol. To improve the reliability, structured questionnaires and various biochemical markers have been developed to estimate alcohol consumption objectively. Further, the pattern
Jonathan Chick; Esko Kemppainen
Thymic stromal lymphopoietin (TSLP) is constitutively expressed in the intestine and is known to regulate inflammation in models of colitis. We show that steady-state TSLP expression requires intestinal bacteria and has an important role in limiting the expansion of colonic T helper type 17 (Th17) cells. Inappropriate expansion of the colonic Th17 cells occurred in response to an entirely benign intestinal microbiota, as determined following the colonization of germ-free C57BL/6 or TSLPR(-/-) mice with the altered Schaedler flora (ASF). TSLP-TSLPR (TSLP receptor) interactions also promoted the expansion of colonic Helios(-)Foxp3(+) regulatory T cells, necessary for the control of inappropriate Th17 responses following ASF bacterial colonization. In summary, these data reveal an important role for TSLP-TSLPR signaling in promoting steady-state mutualistic T-cell responses following intestinal bacterial colonization. PMID:23515135
Mosconi, I; Geuking, M B; Zaiss, M M; Massacand, J C; Aschwanden, C; Kwong Chung, C K C; McCoy, K D; Harris, N L
This is a descriptive exploratory study that aimed to verify nursing students' attitudes facing to the alcoholic drinks, alcoholism and alcoholics, according to their position in face of an attitudes scale items. For data collection, it was used the Scale of Attitudes to alcohol, alcoholism and alcoholic, applied to 144 nursing students. The results showed a tendency to negative attitudes of these students in face of alcoholism, alcoholic person and alcoholic drinks, since most participants were placed in category indifferent or disagree with the positive items, agreeing with negative scale items. We conclude that this trend of negative attitudes is connected to insufficient attention given to the subject during the nurses' education, being verified the need for greater importance to be given to this problem. PMID:23681384
Vargas, Divane; Bittencourt, Marina Nolli
The birth canal provides mammals with a primary maternal inoculum, which develops into distinctive body site-specific microbial communities post-natally. We characterized the distal gut microbiota from birth to weaning in mice. One-day-old mice had colonic microbiota that resembled maternal vaginal communities, but at days 3 and 9 of age there was a substantial loss of intestinal bacterial diversity and dominance of Lactobacillus. By weaning (21 days), diverse intestinal bacteria had established, including strict anaerobes. Our results are consistent with vertical transmission of maternal microbiota and demonstrate a nonlinear ecological succession involving an early drop in bacterial diversity and shift in dominance from Streptococcus to Lactobacillus, followed by an increase in diversity of anaerobes, after the introduction of solid food. Mammalian newborns are born highly susceptible to colonization, and lactation may control microbiome assembly during early development. PMID:23535917
Pantoja-Feliciano, Ida Gisela; Clemente, Jose C; Costello, Elizabeth K; Perez, Maria E; Blaser, Martin J; Knight, Rob; Dominguez-Bello, Maria Gloria
In this bacterial RNA isolation protocol, an "RNA-protective" treatment is followed by lysozyme digestion of the peptidoglycan component of the cell wall. EDTA promotes the loss of the outer membrane of Gram-negative bacteria and allows the lysozyme better access to the peptidoglycan. Cells begin to lyse during digestion in hypotonic lysozyme buffer and lysis is completed by sodium dodecyl sulfate (SDS) and hot phenol:chloroform:isoamyl alcohol (PCA) extraction. SDS and hot phenol disrupt membranes, denature protein (including RNase), and strip proteins from RNA. The separation of the organic phase from the aqueous phase is achieved using Phase Lock Gel, an inert material with a density intermediate between the organic and aqueous samples. The sample is split into three phases: from bottom to top, these are phenol and chloroform (organic phase), the inert gel with the interface material, and the aqueous phase with the RNA. The gel acts as a physical barrier between the sample and the organic phase plus interface. Following organic extraction, the RNA is concentrated by ethanol precipitation. PMID:22949721
A 16S rRNA-targeted probe, MUC-1437, was designed and validated in order to determine the presence and numbers of cells of Akkermansia muciniphila, a mucin degrader, in the human intestinal tract. As determined by fluorescent in situ hybridization, A. muciniphila accounted more than 1% of the total fecal cells and was shown to be a common bacterial component of the human intestinal tract. PMID:18083887
Derrien, Muriel; Collado, M Carmen; Ben-Amor, Kaouther; Salminen, Seppo; de Vos, Willem M
Three cases of chronic pancreatitis occurring in patients with small intestinal diverticulosis and bacterial overgrowth are reported. In two of the cases, pancreatic supplements were therapeutically beneficial (the third being unable to tolerate them). Two of the patients also developed diverticular perforation. The possible nature of the association between small intestinal diverticulosis and chronic pancreatitis is discussed. Images Figure 1 Figure 2 Figure 3 Figure 4
Mahida, Y. R.; Chapman, R. W.; Jewell, D. P.
Chronic intestinal pseudo-obstruction (CIPO) is a syndrome characterized by the presence of recurrent episodes of clinical in- testinal obstruction in the absence of obstructive lesions. Although this syndrome is rare, it causes a high morbidity. It is caused by a disturbance of the intestinal motility, that results in a failure of the progression of the intestinal content. Basically, the failure
M. T. Muñoz; J. A. Solís Herruzo
Lipomas are among the most common benign tumors of the small intestine. They are generally solitary lesions and asymptomatic. The extensive involvement of the small intestine with multiple lipomas is rare. The authors report a case of intestinal lipomatosis of the small bowel in which CT was specific enough to make the diagnosis without resorting to more invasive procedures.
Ormson, M.J.; Stephens, D.H.; Carlson, H.C.
Intestinal failure can be the end result of a wide variety of disease processes that impair the ability of the gut to adequately digest and absorb food. Patients with established intestinal failure may require parenteral nutrition support and\\/or abdominal surgery to reverse the disease process involved. Selected patients with irreversible intestinal failure can be managed in experienced units by home
N. A. Scott; M. H. Irving
The intestinal absorption of benzyl beta-glucoside (BNZ beta glc) contained in the fruit of Prunus mume SIEB. et ZUCC. (Rosaceae), which is traditionally used as a medicinal food in Japan, was studied in rat intestines. BNZ beta glc was absorbed from the mucosal to serosal sides. Its metabolite, benzyl alcohol (BAL), was also detected on both the mucosal and serosal sides. In the presence of phloridzin (Na(+)/glucose cotransporter (SGLT1) inhibitor) or in the absence of Na+ (driving force), BNZ beta glc absorption was significantly decreased. Transport clearance of BNZ beta glc across the brush border membrane decreased as its concentration increased. These results indicate that BNZ beta glc is transported by SGLT1. Metabolic clearance of BNZ beta glc also decreased as its concentration increased. The amount ratio of BNZ beta glc to BAL on the serosal side increased with the increase of BNZ beta glc concentration. The intestinal availability of BNZ beta glc was lower in the absence of Na+ than in the presence of Na+, indicating that the SGLT1-mediated transport of BNZ beta glc increases intestinal availability by decreasing the intestinal extraction ratio. This neutraceutical study concluded that intestinal carrier-mediated transport across the brush border membrane improves the intestinal availability of nutritionally, pharmacologically or physiologically active compounds that undergo intestinal metabolism (first-pass effect). PMID:15716003
Mizuma, Takashi; Nakamura, Maya; Ina, Hiroji; Miyazaki, Toshio; Hayashi, Masahiro
The case of a 44-year-old patient with spontaneous bacterial peritonitis caused by E. coli is described and discussed. The patient with hypalbuminemia, ascites, a medical history of chronic pancreatitis, chronic alcohol abuse and a duodenopancreatectomy 6 months before showed a very slow response to conventional treatment but a good response to homeopathic therapy with Arsenicum album C200 and Pulsatilla C200. The discussion focuses on the methodology of single case evaluations according to cognition based medicine. PMID:17200613
Environmental and hereditary factors, together with lifestyle, are important factors in colon cancer development. Considering\\u000a the increasing incidence of this disease, especially in the developed western world, the last decade has seen much attention\\u000a directed towards understanding possible prevention strategies. Efforts to study the intestinal microbiota and its interaction\\u000a with the host have underlined that disbiosis in colonic bacterial composition
Loredana Baffoni; Francesca Gaggìa; Diana Di Gioia; Bruno Biavati
It has been postulated that dietary fiber's protective effect against the development of colon cancer, diverticular disease, and atherosclerosis may be due to the adsorption and\\/or dilution of intestinal sterols such as bile acids and neutral sterols and their bacterial metabolites by component(s) of fiber. Dietary fiber is made up of four major components-cellulose, hemicellulose, lignin, and pectin. There is
Charles T. L. Huang; G. S. Gopalakrishna; L. Nichols
The alterations in the balance of the normal intestinal bacterial flora of chickens exposed to acidified wood-derived litter were analyzed and compared to those of a control group exposed to nonacidified litter. A total of 1,728 broilers were divided into two groups, with six replicates in each. One group was exposed to dry wood-derived litter, and the other was exposed
Margarita Novoa Garrido; Magne Skjervheim; Hanne Oppegaard; H. Sorum
Cracks in concrete are inevitable and are one of the inherent weaknesses of concrete. Water and other salts seep through these cracks, corrosion initiates, and thus reduces the life of concrete. So there was a need to develop an inherent biomaterial, a self-repairing material which can remediate the cracks and fissures in concrete. Bacterial concrete is a material, which can successfully remediate cracks in concrete. This technique is highly desirable because the mineral precipitation induced as a result of microbial activities is pollution free and natural. As the cell wall of bacteria is anionic, metal accumulation (calcite) on the surface of the wall is substantial, thus the entire cell becomes crystalline and they eventually plug the pores and cracks in concrete. This paper discusses the plugging of artificially cracked cement mortar using Bacillus Pasteurii and Sporosarcina bacteria combined with sand as a filling material in artificially made cuts in cement mortar which was cured in urea and CaCl2 medium. The effect on the compressive strength and stiffness of the cement mortar cubes due to the mixing of bacteria is also discussed in this paper. It was found that use of bacteria improves the stiffness and compressive strength of concrete. Scanning electron microscope (SEM) is used to document the role of bacteria in microbiologically induced mineral precipitation. Rod like impressions were found on the face of calcite crystals indicating the presence of bacteria in those places. Energy- dispersive X-ray (EDX) spectra of the microbial precipitation on the surface of the crack indicated the abundance of calcium and the precipitation was inferred to be calcite (CaCO3).
Ramakrishnan, Venkataswamy; Ramesh, K. P.; Bang, S. S.
Tyrosinases are nearly ubiquitously distributed in all domains of life. They are essential for pigmentation and are important factors in wound healing and primary immune response. Their active site is characterized by a pair of antiferromagnetically coupled copper ions, CuA and CuB, which are coordinated by six histidine residues. Such a "type 3 copper centre" is the common feature of tyrosinases, catecholoxidases and haemocycanins. It is also one of several other copper types found in the multi-copper oxidases (ascorbate oxidase, laccase). The copper pair of tyrosinases binds one molecule of atmospheric oxygen to catalyse two different kinds of enzymatic reactions: (1) the ortho-hydroxylation of monophenols (cresolase activity) and (2) the oxidation of o-diphenols to o-diquinones (catecholase activity). The best-known function is the formation of melanins from L-tyrosine via L-dihydroxyphenylalanine (L-dopa). The complicated hydroxylation mechanism at the active centre is still not completely understood, because nothing is known about their tertiary structure. One main reason for this deficit is that hitherto tyrosinases from eukaryotic sources could not be isolated in sufficient quantities and purities for detailed structural studies. This is not the case for prokaryotic tyrosinases from different Streptomyces species, having been intensively characterized genetically and spectroscopically for decades. The Streptomyces tyrosinases are non-modified monomeric proteins with a low molecular mass of ca. 30kDa. They are secreted to the surrounding medium, where they are involved in extracellular melanin production. In the species Streptomyces, the tyrosinase gene is part of the melC operon. Next to the tyrosinase gene (melC2), this operon contains an additional ORF called melC1, which is essential for the correct expression of the enzyme. This review summarizes the present knowledge of bacterial tyrosinases, which are promising models in order to get more insights in structure, enzymatic reactions and functions of "type 3 copper" proteins in general. PMID:16423650
Claus, Harald; Decker, Heinz
We assessed changes in forward vection following alcohol consumption, and found that alcohol consumption enhanced vection. This result indicates that alcohol can affect psychophysical processes responsible for self-motion perception. PMID:23964383
Seno, Takeharu; Nakamura, Shinji
... Drinking Statistics What Is A Standard Drink? Moderate & Binge Drinking Alcohol's Effects on the Body Alcohol Use Disorders ... Disorders Other Substance Abuse HIV/AIDS Overview of Alcohol Consumption People drink to socialize, celebrate, and relax. ...
This monograph presents papers delivered at a national conference on alcohol aging, sponsored by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), that discuss epidemiology; basic genetic, biological, and developmental mechanisms; the course...
A. M. Hegedus E. S. L. Gomberg R. A. Zucker
SUMMARY Salmonella enterica serotype Typhimurium thrives in the lumen of the acutely inflamed intestine, which suggests that this pathogen is resistant to antimicrobials encountered in this environment. However, the identity of these antimicrobials and the corresponding bacterial resistance genes remains elusive. Here we show that enteric infection with S. Typhimurium evoked marked interleukin (IL)–22/IL-17 mediated induction in intestinal epithelial cells of lipocalin-2, an antimicrobial protein that prevents bacterial iron acquisition. Lipocalin-2 accumulated in the intestinal lumen of rhesus macaques during S. Typhimurium infection. Resistance to lipocalin-2, mediated by the iroBCDE iroN locus, conferred a competitive advantage upon the S. Typhimurium wild-type in colonizing the inflamed intestine of wild-type, but not of lipocalin-2 deficient mice. These data support that resistance to lipocalin-2 defines a specific adaptation to growth in the inflamed intestine.
Raffatellu, Manuela; George, Michael D.; Akiyama, Yuko; Hornsby, Michael J.; Nuccio, Sean-Paul; Paixao, Tatiane A.; Butler, Brian P.; Chu, Hiutung; Santos, Renato L.; Berger, Thorsten; Mak, Tak W.; Tsolis, Renee M.; Bevins, Charles L.; Solnick, Jay V.; Dandekar, Satya; Baumler, Andreas J.
Protozoa that parasitize the human intestine and cause disease include Entamoeba histolytica, Giardia lamblia, Cryptosporidium parvum, Cyclospora cayetanensis, Isospora belli, and the microsporidia (which are now classified as fungi). The new and broad-spectrum agent nitazoxanide now has an Food and Drug Administration indication for the treatment of cryptosporidiosis and giardiasis in children, making C. parvum for the first time a
William A. Petri Jr
Over the lifetime of the animal, there are many changes in the function of the body's organ systems. In the gastrointestinal tract there is a general modest decline in the function of the esophagus, stomach, colon, pancreas and liver. In the small intestine, there may be subtle alterations in the intestinal morphology, as well as a decline in the uptake of fatty acids and sugars. The malabsorption may be partially reversed by aging glucagon-like peptide 2 (GLP2) or dexamethasone. Modifications in the type of lipids in the diet will influence the intestinal absorption of nutrients: for example, in mature rats a diet enriched with saturated as compared with polysaturated fatty acids will enhance lipid and sugar uptake, whereas in older animals the opposite effect is observed. Thus, the results of studies of the intestinal adaptation performed in mature rats does not necessarily apply in older animals. The age-associated malabsorption of nutrients that occurs with aging may be one of the several factors which contribute to the malnutrition that occurs with aging. PMID:17171784
Drozdowski, Laurie; Thomson, Alan B R
The noninvasive assessment of intestinal permeability in humans has a 20-year history. Because the tests are increasingly used in clinical practice and research and because there is much controversy, we reviewed the literature and outlined the potential and possible shortcomings of these procedures. Data was obtained from personal files and from a systemic search through MEDLINE and EMBASE. The principle
Ingvar Bjarnason; Andrew Macpherson; Daniel Hollander
From 1955 through 1964, the authors were actively engaged in experimental and clinical studies concerned with intestinal antisepsis, a form of antimicrobial prophylaxis used by the surgeon to lower the high rate of infectious complications following colorectal operations. Controversy has existed regarding the protective action of antibacterial agents and whether such a regimen has significant advantage over simple mechanical cleansing.
Isidore Cohn; George H. Bornside
The National Institute on Alcohol Abuse and Alcoholism (NIAAA) Alcohol Problems Science Database (ETOH) is "the most comprehensive online bibliographic database containing over 100,000 records on alcohol abuse and alcoholism." This database (updated monthly) contains scientific literature from the late 1960s to the present, as well as a recently added thesaurus of alcohol and other drug terms. The Web site offers four search options and a useful Quick Search Guide for help with each one.
The mammalian intestine is colonized with a diverse community of bacteria that perform many beneficial functions but can threaten host health upon tissue invasion. Epithelial cell-intrinsic innate immune responses are essential to limit the invasion of both commensal and pathogenic bacteria and maintain beneficial host-bacterial relationships; however, little is known about the role of various cellular processes, notably autophagy, in controlling bacterial interactions with the intestinal epithelium in vivo. We demonstrate that intestinal epithelial cell autophagy protects against tissue invasion by both opportunistically invasive commensals and the invasive intestinal pathogen Salmonella Typhimurium. Autophagy is activated following bacterial invasion of epithelial cells through a process requiring epithelial cell-intrinsic signaling via the innate immune adaptor protein MyD88. Additionally, mice deficient in intestinal epithelial cell autophagy exhibit increased dissemination of invasive bacteria to extraintestinal sites. Thus, autophagy is an important epithelial cell-autonomous mechanism of antibacterial defense that protects against dissemination of intestinal bacteria. PMID:23768496
Benjamin, Jamaal L; Sumpter, Rhea; Levine, Beth; Hooper, Lora V
With the growing number of completely sequenced bacterial genes, accurate gene prediction in bacterial genomes remains an important problem. Although the existing tools predict genes in bacterial genomes with high overall accuracy, their ability to pinpoint the translation start site remains unsatisfactory. In this paper, we present a novel approach to bacterial start site prediction that takes into account multiple
Sridhar S. Hannenhalli; William S. Hayes; Artemis G. Hatzigeorgiou; James W. Fickett
Toll-like receptors (TLRs) recognize distinct microbial components and induce innate immune responses. TLR5 is triggered by bacterial flagellin. Here we generated Tlr5?\\/? 1mice and assessed TLR5 function in vivo. Unlike other TLRs, TLR5 was not expressed on conventional dendritic cells or macrophages. In contrast, TLR5 was expressed mainly on intestinal CD11c+ lamina propria cells (LPCs). CD11c+ LPCs detected pathogenic bacteria
Satoshi Uematsu; Myoung Ho Jang; Nicolas Chevrier; Zijin Guo; Yutaro Kumagai; Masahiro Yamamoto; Hiroki Kato; Nagako Sougawa; Hidenori Matsui; Hirotaka Kuwata; Hiroaki Hemmi; Cevayir Coban; Taro Kawai; Ken J Ishii; Osamu Takeuchi; Masayuki Miyasaka; Kiyoshi Takeda; Shizuo Akira
The effect of vasoactive intestinal polypeptide (VIP) on intestinal water and electrolyte transport and transmucosal potential difference was investigated in the dog jejunum in vivo and compared to secretion induced by cholera toxin. Isolated jejunal loops were perfused with a plasma-like electrolyte solution. VIP (0.08 ?g/kg per min) was administered directly into the superior mesenteric artery by continuous infusion over 1 h. From a dye dilution method, it was estimated that a mean plasma VIP concentration of 12,460 pg/ml reached the loops. VIP caused secretion of water and electrolytes; for example, chloride: control, 8 ?eq/cm per h absorption; VIP, 92 ?eq/cm per h secretion. A marked increase in transmucosal potential difference (control, ?1.0 mV; VIP, ?5.9 mV, lumen negative) occurred within 1 min after starting VIP infusion. Analysis of unidirectional fluxes showed increased plasma-to-lumen flux of sodium and chloride and decreased lumen-to-plasma flux of sodium. Chloride and bicarbonate were actively secreted against an electrochemical gradient. Although sodium secretion occurred down an electrochemical gradient, flux ratio analysis suggested a component of active sodium secretion. VIP caused a slight increase in protein output into the loops; light microscopy revealed capillary dilatation and closed intercellular spaces. The effect of VIP was readily reversible. Except for the delayed onset of secretion, the effect of cholera toxin was qualitatively similar to VIP; however, capillary dilatation and increased protein output were not noted with cholera toxin. Images
Krejs, Guenter J.; Barkley, Ronald M.; Read, Nicholas W.; Fordtran, John S.
Intestinal epithelial restitution is the first part in the process of mucosal repair after injury in the intestine. Integrity of the intestinal mucosal barrier is important as a first line of defense against bacteria and endotoxin. Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in extremely low birth weight infants, but its mechanisms are not well defined. Abnormal bacterial colonization, immature barrier function, innate immunity activation and inflammation likely play a role. Lipopolysaccharide (LPS) binding protein (LBP) is secreted by enterocytes in response to inflammatory stimuli and has concentration-dependent effects. At basal concentrations, LBP stimulates the inflammatory response by presenting LPS to its receptor. However, at high concentrations, LBP is able to neutralize LPS and prevent an exaggerated inflammatory response. We sought to determine how LBP would affect wound healing in an in vitro model of intestinal cell restitution and protect against intestinal injury in a rodent model of NEC. Immature intestinal epithelial cells (IEC-6) were seeded in poly-l-lysine coated 8 chamber slides and grown to confluence. A 500?m wound was created using a cell scraper mounted on the microscope to achieve uniform wounding. Media was replaced with media containing LPS +/? LBP. Slide wells were imaged after 0, 8, and 24 hours and then fixed. Cellular restitution was evaluated via digital images captured on an inverted microscope and wound closure was determined by automated analysis. TLR4 was determined by rtPCR after RNA isolation from wounded cells 24 hours after treatment. LPS alone attenuated wound healing in immature intestinal epithelium. This attenuation is reversed by 24 hours with increasing concentrations of LBP so that wound healing is equivalent to control (p< 0.001). TLR4 was increased with LPS alone but levels returned to that of control after addition of LBP in the higher concentrations. LBP had no effect on the development of intestinal injury when given during our rodent model of NEC. Abnormal bacterial colonization and activation of innate immunity by LPS are likely involved in the pathogenesis of NEC. The attentuation of wound healing was reversed when LBP was added to LPS but only in the higher concentrations. At these same concentrations of LBP, TLR4 was decreased to that of control. These results indicate that LBP may be a novel therapeutic strategy to facilitate wound healing after the acute phase of NEC and other forms of intestinal injury.
Richter, Juli M.; Schanbacher, Brandon L.; Huang, Hong; Xue, Jianjing; Bauer, John A.; Giannone, Peter J.
Ethanol is widely consumed and is associated with an increasing global health burden. Several reviews have addressed the effects of ethanol and its oxidative metabolite, acetaldehyde, on the gastrointestinal (GI) tract, focusing on carcinogenic effects or alcoholic liver disease. However, both the oxidative and the nonoxidative metabolites of ethanol can affect the epithelial barrier of the small and large intestines, thereby contributing to GI and liver diseases. This review outlines the possible mechanisms of ethanol metabolism as well as the effects of ethanol and its metabolites on the intestinal barrier. Limited studies in humans and supporting in vitro data have indicated that ethanol as well as mainly acetaldehyde can increase small intestinal permeability. Limited evidence also points to increased colon permeability following exposure to ethanol or acetaldehyde. In vitro studies have provided several mechanisms for disruption of the epithelial barrier, including activation of different cell-signaling pathways, oxidative stress, and remodeling of the cytoskeleton. Modulation via intestinal microbiota, however, should also be considered. In conclusion, ethanol and its metabolites may act additively or even synergistically in vivo. Therefore, in vivo studies investigating the effects of ethanol and its byproducts on permeability of the small and large intestines are warranted. PMID:23815146
Elamin, Elhaseen E; Masclee, Ad A; Dekker, Jan; Jonkers, Daisy M
A major challenge in the human metagenomics field is to identify associations of the bacterial genes and human phenotypes and act to modulate microbial populations in order to improve human health and wellbeing. MetaHIT project addresses this ambitious challenge by developing and integrating a number of necessary approaches within the context of the gut microbiome. Among the first results is the establishment of a broad catalog of the human gut microbial genes, which was achieved by an original application of the new generation sequencing technology. The catalog contains 3.3 million non-redundant genes, 150-fold more than the human genome equivalent and includes a large majority of the gut metagenomic sequences determined across three continents, Europe, America and Asia. Its content corresponds to some 1000 bacterial species, which likely represent a large fraction of species associated with humankind intestinal tract. The catalog enables development of the gene profiling approaches aiming to detect associations of bacterial genes and phenotypes. These should lead to the speedy development of diagnostic and prognostic tools and open avenues to reasoned approaches to the modulation of the individual's microbiota in order to optimize health and well-being. PMID:20889001
Dusko Ehrlich, S
Bacteria causing infections in hospitalized patients are increasingly antibiotic resistant. Classical infection control practices are only partially effective at preventing spread of antibiotic-resistant bacteria within hospitals. Because the density of intestinal colonization by the highly antibiotic-resistant bacterium vancomycin-resistant Enterococcus (VRE) can exceed 109 organisms per gram of feces, even optimally implemented hygiene protocols often fail. Decreasing the density of intestinal colonization, therefore, represents an important approach to limit VRE transmission. We demonstrate that reintroduction of a diverse intestinal microbiota to densely VRE-colonized mice eliminates VRE from the intestinal tract. While oxygen-tolerant members of the microbiota are ineffective at eliminating VRE, administration of obligate anaerobic commensal bacteria to mice results in a billionfold reduction in the density of intestinal VRE colonization. 16S rRNA gene sequence analysis of intestinal bacterial populations isolated from mice that cleared VRE following microbiota reconstitution revealed that recolonization with a microbiota that contains Barnesiella correlates with VRE elimination. Characterization of the fecal microbiota of patients undergoing allogeneic hematopoietic stem cell transplantation demonstrated that intestinal colonization with Barnesiella confers resistance to intestinal domination and bloodstream infection with VRE. Our studies indicate that obligate anaerobic bacteria belonging to the Barnesiella genus enable clearance of intestinal VRE colonization and may provide novel approaches to prevent the spread of highly antibiotic-resistant bacteria.
Bucci, Vanni; Caballero, Silvia; Djukovic, Ana; Toussaint, Nora C.; Equinda, Michele; Lipuma, Lauren; Ling, Lilan; Gobourne, Asia; No, Daniel; Taur, Ying; Jenq, Robert R.; van den Brink, Marcel R. M.; Xavier, Joao B.
Bacteria causing infections in hospitalized patients are increasingly antibiotic resistant. Classical infection control practices are only partially effective at preventing spread of antibiotic-resistant bacteria within hospitals. Because the density of intestinal colonization by the highly antibiotic-resistant bacterium vancomycin-resistant Enterococcus (VRE) can exceed 10(9) organisms per gram of feces, even optimally implemented hygiene protocols often fail. Decreasing the density of intestinal colonization, therefore, represents an important approach to limit VRE transmission. We demonstrate that reintroduction of a diverse intestinal microbiota to densely VRE-colonized mice eliminates VRE from the intestinal tract. While oxygen-tolerant members of the microbiota are ineffective at eliminating VRE, administration of obligate anaerobic commensal bacteria to mice results in a billionfold reduction in the density of intestinal VRE colonization. 16S rRNA gene sequence analysis of intestinal bacterial populations isolated from mice that cleared VRE following microbiota reconstitution revealed that recolonization with a microbiota that contains Barnesiella correlates with VRE elimination. Characterization of the fecal microbiota of patients undergoing allogeneic hematopoietic stem cell transplantation demonstrated that intestinal colonization with Barnesiella confers resistance to intestinal domination and bloodstream infection with VRE. Our studies indicate that obligate anaerobic bacteria belonging to the Barnesiella genus enable clearance of intestinal VRE colonization and may provide novel approaches to prevent the spread of highly antibiotic-resistant bacteria. PMID:23319552
Ubeda, Carles; Bucci, Vanni; Caballero, Silvia; Djukovic, Ana; Toussaint, Nora C; Equinda, Michele; Lipuma, Lauren; Ling, Lilan; Gobourne, Asia; No, Daniel; Taur, Ying; Jenq, Robert R; van den Brink, Marcel R M; Xavier, Joao B; Pamer, Eric G
ñ Chronic alcohol abuse negatively influences somatic and psychic health, leads to alcohol damage of many human organs, and causes loss of control of behavior. Ethanol is a multiorgan poison, which causes a damage of liver, pancreas, gastric mucosa, nervous system and coronary arteries. In Poland alcohol addicts constitute 3% of total population. The liver is an organ especially susceptible
Halina Cicho; Monika Grzyb
This study investigates the effects of alcohol advertising on adolescent alcohol consumption. The theory of an industry response function and evidence from prior studies indicate the importance of maximizing the variance in advertising measures. Monitoring the Future (MTF) and National Longitudinal Survey of Youth 1997 (NLSY97) data are augmented with alcohol advertising, originating on the market level, for five media.
Henry Saffer; Dhaval Dave
The purpose of this paper is to empirically examine the relationship between alcohol advertising bans and alcohol consumption. Most prior studies have found no effect of advertising on total alcohol consumption. A simple economic model is provided which explains these prior results. The data set used in this study is a pooled time series of data from 20 countries over
Henry Saffer; Dhaval Dave
The purpose of this paper is to empirically examine the relationship between alcohol advertising bans and alcohol consumption. Most prior studies have found no effect of advertising on total alcohol consumption. A simple economic model is provided which explains these prior results. The data set used in this study is a pooled time series of data from 20 countries over
Obstruction of bile flow results in bacterial proliferation and mucosal injury in the small intestine that can lead to the translocation of bacteria across the epithelial barrier and systemic infection. These adverse effects of biliary obstruction can be inhibited by administration of bile acids. Here we show that the farnesoid X receptor (FXR), a nuclear receptor for bile acids, induces genes involved in enteroprotection and inhibits bacterial overgrowth and mucosal injury in ileum caused by bile duct ligation. Mice lacking FXR have increased ileal levels of bacteria and a compromised epithelial barrier. These findings reveal a central role for FXR in protecting the distal small intestine from bacterial invasion and suggest that FXR agonists may prevent epithelial deterioration and bacterial translocation in patients with impaired bile flow.
Inagaki, Takeshi; Moschetta, Antonio; Lee, Youn-Kyoung; Peng, Li; Zhao, Guixiang; Downes, Michael; Yu, Ruth T.; Shelton, John M.; Richardson, James A.; Repa, Joyce J.; Mangelsdorf, David J.; Kliewer, Steven A.
Obstruction of bile flow results in bacterial proliferation and mucosal injury in the small intestine that can lead to the translocation of bacteria across the epithelial barrier and systemic infection. These adverse effects of biliary obstruction can be inhibited by administration of bile acids. Here we show that the farnesoid X receptor (FXR), a nuclear receptor for bile acids, induces genes involved in enteroprotection and inhibits bacterial overgrowth and mucosal injury in ileum caused by bile duct ligation. Mice lacking FXR have increased ileal levels of bacteria and a compromised epithelial barrier. These findings reveal a central role for FXR in protecting the distal small intestine from bacterial invasion and suggest that FXR agonists may prevent epithelial deterioration and bacterial translocation in patients with impaired bile flow. bacteria | biliary obstruction | epithelial barrier | ileum
Inagaki, Takeshi; Moschetta, Antonio; Lee, Youn-Kyoung; Peng, Li; Zhao, Guixiang; Downes, Michael; Yu, Ruth T.; Shelton, John M.; Richardson, James A.; Repa, Joyce J.; Mangelsdorf, David J.; Kliewer, Steven A.
Obstruction of bile flow results in bacterial proliferation and mucosal injury in the small intestine that can lead to the translocation of bacteria across the epithelial barrier and systemic infection. These adverse effects of biliary obstruction can be inhibited by administration of bile acids. Here we show that the farnesoid X receptor (FXR), a nuclear receptor for bile acids, induces genes involved in enteroprotection and inhibits bacterial overgrowth and mucosal injury in ileum caused by bile duct ligation. Mice lacking FXR have increased ileal levels of bacteria and a compromised epithelial barrier. These findings reveal a central role for FXR in protecting the distal small intestine from bacterial invasion and suggest that FXR agonists may prevent epithelial deterioration and bacterial translocation in patients with impaired bile flow. PMID:16473946
Inagaki, Takeshi; Moschetta, Antonio; Lee, Youn-Kyoung; Peng, Li; Zhao, Guixiang; Downes, Michael; Yu, Ruth T; Shelton, John M; Richardson, James A; Repa, Joyce J; Mangelsdorf, David J; Kliewer, Steven A
Carbohydrates are an important component of the diet. The carbohydrates that we ingest range from simple monosaccharides (glucose, fructose and galactose) to disaccharides (lactose, sucrose) to complex polysaccharides. Most carbohydrates are digested by salivary and pancreatic amylases, and are further broken down into monosaccharides by enzymes in the brush border membrane (BBM) of enterocytes. For example, lactase-phloridzin hydrolase and sucrase-isomaltase are two disaccharidases involved in the hydrolysis of nutritionally important disaccharides. Once monosaccharides are presented to the BBM, mature enterocytes expressing nutrient transporters transport the sugars into the enterocytes. This paper reviews the early studies that contributed to the development of a working model of intestinal sugar transport, and details the recent advances made in understanding the process by which sugars are absorbed in the intestine. PMID:16586532
Drozdowski, Laurie A; Thomson, Alan B R
Conclusions Should there be difficulty in finding the site of the obstruction:-\\u000a \\u000a \\u000a (a) \\u000a \\u000a Follow engorged coil of intestines upwards and down wards until point of obstruction is reached or turn out all the intestines.\\u000a \\u000a \\u000a \\u000a \\u000a (b) \\u000a \\u000a Remove all fluid from Douglas’ pouch and loins by irrigation with sterile water.\\u000a \\u000a \\u000a \\u000a \\u000a (c) \\u000a \\u000a Eestore colour of bowel, and establish peristaltic movements by heating with neutral
J. S. M’Ardle
The clinical manifestations of cystic fibrosis (CF) result from dysfunction of the cystic fibrosis transmembrane regulator protein (CFTR). The majority of people with CF have a limited life span as a consequence of CFTR dysfunction in the respiratory tract. However, CFTR dysfunction in the gastrointestinal (GI) tract occurs earlier in ontogeny and is present in all patients, regardless of genotype. The same pathophysiologic triad of obstruction, infection, and inflammation that causes disease in the airways also causes disease in the intestines. This article describes the effects of CFTR dysfunction on the intestinal tissues and the intraluminal environment. Mouse models of CF have greatly advanced our understanding of the GI manifestations of CF, which can be directly applied to understanding CF disease in humans. PMID:23788646
De Lisle, Robert C; Borowitz, Drucy
Most nonsporing anaerobes of the intestinal tract use the Embden-Meyerhof- Parnas scheme to ferment carbohydrates. Almost all of them oxidize pyruvate, the key fermentation intermediate, to acetyl coenzyme A and CO2 with reduction of a low-potential electron acceptor. H2 is formed from the low potential acceptor or from NADH. Pyruvate is a precursor of lactate, and phosphoenolpyruvate is a precursor
Terry L. Miller; M. J. Wolin
In this overview the actual international knowledge regarding phenomenons and their proven or speculated mechanisms of adaptative microecological, hormonal and immunological responses to neuroemotional stress conditions including space-flights is represented. In most cases a decreased stability of the intestinal microflora provokes further reactions of the body. The necessity to predict the various possible disorders and to find optimal measures for their prophylaxis and elimination is emphasized. PMID:3657919
Lizko, N N
There has been an ample interest in delivery of therapeutic molecules using live cells. Oral delivery has been stipulated as best way to deliver live cells to humans for therapy. Colon, in particular, is a part of gastrointestinal (GI) tract that has been proposed to be an oral targeted site. The main objective of these oral therapy procedures is to deliver live cells not only to treat diseases like colorectal cancer, inflammatory bowel disease, and other GI tract diseases like intestinal obstruction and gastritis, but also to deliver therapeutic molecules for overall therapy in various diseases such as renal failure, coronary heart disease, hypertension, and others. This review provides a comprehensive summary of recent advancement in colon targeted live bacterial cell biotherapeutics. Current status of bacterial cell therapy, principles of artificial cells and its potentials in oral delivery of live bacterial cell biotherapeutics for clinical applications as well as biotherapeutic future perspectives are also discussed in our review.
Prakash, Satya; Malgorzata Urbanska, Aleksandra
Alcoholic liver disease (ALD) is typically associated with folate deficiency, which is the result of reduced dietary folate intake, intestinal malabsorption, reduced liver uptake and storage, and increased urinary folate excretion. Folate deficiency favors the progression of liver disease through mechanisms that include its effects on methionine metabolism with consequences for DNA synthesis and stability and the epigenetic regulation of gene expression involved in pathways of liver injury. This paper reviews the pathogenesis of ALD with particular focus on ethanol-induced alterations in methionine metabolism, which may act in synergy with folate deficiency to decrease antioxidant defense as well as DNA stability while regulating epigenetic mechanisms of relevant gene expressions. We also review the current evidence available on potential treatments of ALD based on correcting abnormalities in methionine metabolism and the methylation regulation of relevant gene expressions. PMID:23136133
Medici, Valentina; Halsted, Charles H
Mediterranean diet or extended fasting's influence on changing the intestinal microflora, immunoglobulin A secretion and clinical outcome in patients with rheumatoid arthritis and fibromyalgia: an observational study
BACKGROUND: Alterations in the intestinal bacterial flora are believed to be contributing factors to many chronic inflammatory and degenerative diseases including rheumatic diseases. While microbiological fecal culture analysis is now increasingly used, little is known about the relationship of changes in intestinal flora, dietary patterns and clinical outcome in specific diseases. To clarify the role of microbiological culture analysis we
Andreas Michalsen; Markus Riegert; Rainer Lüdtke; Marcus Bäcker; Jost Langhorst; Myriam Schwickert; Gustav J Dobos
Background and aims. Luminal bacteria have been implicated in the pathogenesis of inflammatory bowel diseases. Exposure of intestinal epithelial cells (IEC) to bacterial components potentially initiates intestinal inflammation by release of chemokines and recruitment of inflammatory cells. We analyzed receptor expression and signaling pathways involved in activation of human primary IEC and carcinoma-derived cell lines by lipopolysaccharide (LPS). Materials and
Ulrich Böcker; Oleksandr Yezerskyy; Peter Feick; Tobias Manigold; Asit Panja; Uwe Kalina; Frank Herweck; Siegbert Rossol; Manfred V. Singer
|Describes patterns of problem drinking in rural areas, suggests factors which may influence the comparatively lower rates of alcoholism among rural residents, discusses the types of alcohol treatment available in rural communities, and offers preliminary ideas for applying the alcoholism-reducing factors of rural life to preventing alcoholism in…
Traces the history of alcohol use in the United States from the colonial period to the present. Discusses changes in public attitudes toward drinking. Explores attempts at prohibition, alcohol preferences, the relationship between alcohol consumption and economic prosperity, and the dichotomy of alcohol as a part of a European heritage that is…
Rorabaugh, W. J.
|Traces the history of alcohol use in the United States from the colonial period to the present. Discusses changes in public attitudes toward drinking. Explores attempts at prohibition, alcohol preferences, the relationship between alcohol consumption and economic prosperity, and the dichotomy of alcohol as a part of a European heritage that is…
Rorabaugh, W. J.
Rather high prevalence rates of alcohol abuse in the elderly have been reported in the literature. However, there is some evidence that many elderly persons with alcohol problems are not identified, probably due to the nonspecificity of alcohol-related presentations in old individuals. Thus, there is an ongoing discussion on appropriate diagnostic criteria for alcohol dependence in elder people who frequently
Tilman Wetterling; Clemens Veltrup; Ulrich John; Martin Driessen
This review categorizes five main uses of pharmacologic agents in the treatment of alcoholism: reversing the active pharmacologic effects of alcohol; controlling withdrawal symptoms; blocking the desire for alcohol use; treating psychiatric symptoms induced by alcohol and other drugs; and treating indenpendent, but concurrent, psychopathologic conditions. No medication, including stimulants such as caffeine, has been found to acutally reverse the
Norman S. Miller
Alcohol dependence and alcohol intoxication are important risk factors for suicidal behavior. However, the mechanism for the relationship remains unclear. This review presents a conceptual framework relating alcohol to suicidal behavior. Distal risk factors create a statistical potential for suicide. Alcohol dependence, as well as associated comorbid psychopathology and negative life events, act as distal risk factors for suicidal behavior.
Michael R Hufford
A new distillation equipment for alcohol which consists mainly of a brief concentrating column a, a concentrating column b, a compressor C to compress alcohol vapor generated in column B and water evaporator D heated by the compressed alcohol vapor is developed and this especially fits for a distillation source of a glue like solution obtained by alcohol fermentation because
T. Kawase; K. Sawai
Adult intestinal allografts have demonstrated high immunogenicity in human transplantation, making the search for new and\\u000a more favorable grafts an actual problem. Accepting that fetal and newborn immune systems are relatively immature, their intestines\\u000a could be ideal sources for organ donation. The purpose of this study was to compare the immunogenicity of fetal, newborn,\\u000a and adult intestine for selection of
M. F. Lopes; A. M. S. Cabrita; J. A. B. Patrício
Aims: The impact of emotional states on alcohol craving has so far mainly been investigated in abstinent and actively consuming alcohol addicts. Alcohol craving and the variables that influence alcohol craving have not yet been examined in non-addicted, alcohol abusing drinkers and non-abusing occasional alcohol drinkers. Methods: In this study 50 problem drinkers and 50 occasional alcohol drinkers were investigated.
SABINE M. GRUSSER; CHANTAL P. MORSEN; HERTA FLOR
In the United States, approximately 100,000 deaths are attributed to alcohol abuse each year. In 2009, the World Health Organization listed alcohol use as one of the leading causes of the global burden of disease and injury. Alcoholic liver disease, a direct result of chronic alcohol abuse, insidiously destroys the normal functions of the liver. The end result of the disease, cirrhosis, culminates in a dysfunctional and diffusely scarred liver. This article discusses the clinical manifestations, imaging considerations, and treatment of alcoholic liver disease and cirrhosis. Normal liver function, liver hemodynamics, the disease of alcoholism, and the deleterious effects of alcohol also are reviewed. PMID:23861518
Penny, Steven M
Alcohol consumption increases subjective sexual desire, arousal, and pleasure for many women, although it lowers physiological\\u000a arousal. Despite the general belief that alcohol disinhibits female sexual behaviors, alcohol leads to changes in sexual behavior\\u000a only for a minority of women. Expectancies about the effects of alcohol on sexual behavior may be important mediators of the\\u000a alcohol-sexual behavior linkage. There also
Linda J. Beckman; Kimberly T. Ackerman
ABSTRACT. Objective: The question addressed ,in this review is whether aggregate alcohol advertising increases alcohol consumption among,college students. Both the level of alcohol-related problems on college campuses,and the level of alcohol,advertising are high. Some researchers have concluded ,that the cultural myths and symbols used in alcohol advertisements have powerful meanings,for college students and affect intentions to drink. There is, however,
Alcohol (ethanol) is absorbed slowly from the stomach and rapidly from the small intestine, and the rate of its absorption depends on the rate of gastric emptying. When gastric emptying is fast, the absorption of alcohol is fast. When gastric emptying is slow the absorption of alcohol is delayed and peak blood alcohol concentrations are reduced. Alterations of the gastric emptying rate, which may have a physiologic, pharmacologic or pathologic cause, markedly influence the rate of alcohol absorption. The gastric emptying rate makes an important contribution to inter- and intraindividual variations in the rate of alcohol absorption and therefore the timing and magnitude of the acute intoxicating effect of an oral dose of alcohol.
The intestinal microbiota consists of over 1000 species, which play key roles in gut physiology and homeostasis. Imbalances in the composition of this bacterial community can lead to transient intestinal dysfunctions and chronic disease states. Understanding how to manipulate this ecosystem is thus essential for treating many disorders. In this study, we took advantage of recently developed tools for deep sequencing and phylogenetic clustering to examine the long-term effects of exogenous microbiota transplantation combined with and without an antibiotic pretreatment. In our rat model, deep sequencing revealed an intestinal bacterial diversity exceeding that of the human gut by a factor of two to three. The transplantation produced a marked increase in the microbial diversity of the recipients, which stemmed from both capture of new phylotypes and increase in abundance of others. However, when transplantation was performed after antibiotic intake, the resulting state simply combined the reshaping effects of the individual treatments (including the reduced diversity from antibiotic treatment alone). Therefore, lowering the recipient bacterial load by antibiotic intake prior to transplantation did not increase establishment of the donor phylotypes, although some dominant lineages still transferred successfully. Remarkably, all of these effects were observed after 1 mo of treatment and persisted after 3 mo. Overall, our results indicate that the indigenous gut microbial composition is more plastic that previously anticipated. However, since antibiotic pretreatment counterintuitively interferes with the establishment of an exogenous community, such plasticity is likely conditioned more by the altered microbiome gut homeostasis caused by antibiotics than by the primary bacterial loss.
Manichanh, Chaysavanh; Reeder, Jens; Gibert, Prudence; Varela, Encarna; Llopis, Marta; Antolin, Maria; Guigo, Roderic; Knight, Rob; Guarner, Francisco
This resource provides detailed instructions for carrying out several laboratory exercises relating to bacterial transformation and conjugation. In this multi-session experiment, students are exposed to various techniques in microbiology, including bacterial transformation and assay and sterile techniques.
Roberta Ellington (Northwestern University;); John Mordacq (Northwestern University;)
Bacterial communities in the large intestines of pigs were compared using terminal restriction fragment length polymorphism (T-RFLP) analysis targeting the 16S ribosomal DNA. The pigs were fed different experimental diets based on either modified standard feed or cooked rice supplemented with dietary fibers. After feeding of the animals with the experimental diets for 2 weeks, differences in the bacterial community
THOMAS D. LESER; RIKKE HVID LINDECRONA; TIM K. JENSEN; BENT B. JENSEN; K. Moller
The aim of this study was to investigate in vitro the effects of pediocin A [a bacteriocin produced by lactic acid bacteria (LAB) Pediococcus pentosaceus FBB61] on microbial metabolism in the small and large intestine of pigs. Pediocin A was partially purified by ion exchange chromatography and added to an in vitro fermentation system. The intestinal inoculum was collected from pigs immediately after slaughter, diluted with a buffer, and dispensed into fermentation syringes and vessels of the 2 experimental groups: 1) Bac+ = cecal liquor + predigested diet + pediocin A (final concentration 160 activity units/mL); 2) Bac- = cecal liquor + predigested diet + partially purified supernatant of P. pentosaceus FBB61-2. Intestinal microbial growth was monitored using the cumulative gas production technique; the kinetics of fermentation, bacterial counts, VFA, ammonia, polyamines, and p-cresol production were analyzed. Pediocin A had almost no effects on small intestine fermentation parameters, whereas in the cecum pediocin A decreased gas production (-16%; P < 0.05), ammonia, and VFA production (-52 and -21%, respectively, after 24 h; P < 0.001) compared with the control group. Significant inhibition of clostridia and LAB occurred in cecal fermentations: the Bac+ group yielded a decreased number of clostridia and LAB in cecal fermentations (8.19 and 7.80 cfu/mL, respectively) compared with Bac- (9.32 and 8.95 cfu/mL, respectively; P < 0.001). The low clostridia counts in the pediocin-treated group may also explain the reduced concentration of the carcinogenic compound p-cresol (-88%; P < 0.01). Our results suggest that pediocin A could be an alternative to replace antibiotic growth promoters for the prophylaxis of enteric diseases and to improve production of farm animals. PMID:19251932
Casadei, G; Grilli, E; Piva, A
The goal of this study is to develop and optimize the process technology for the production of ethanol using the bacteria Zymomonas mobilis. Specifically, the process and operating conditions will be studied to maximize the yield of ethanol. The experimental design is described using both batch and continuous cultures with glucose as the substrate. Separation methods, therefore, will be developed to remove the alcohol from the fermentation media to prevent the inhibitory effects of ethanol on Z. mobilis. Vacuum fermentation and solvent extraction can be used to separate the alcohol from the media. Kinetic data will be obtained from both the batch and continuous fermentors. The kinetic data can be correlated using mathematical models. Mathematical models for Z. mobilis will be developed for the effect of pH, temperature and nutrient composition on the specific growth rate. A model will also be developed to account for the possible product inhibition by ethanol. Dynamic tests will also be conducted on the continuous system to determine how fast the fermentation will respond to environmental changes. The simultaneous hydrolysis of cellulose to glucose and fermentation of glucose to ethanol is one of the most exciting possibilities. A literature survey will be made to determine the compatibility of conducting the hydrolysis reaction along with the bacterial fermentation. The final objective will be to make an economic assessment of the process of producing ethanol using Z. mobilis.
Background and Aims Excessive uptake of commensal bacterial antigens through a permeable intestinal barrier may influence host responses to specific antigen in a genetically predisposed host. The aim of this study was to investigate whether intestinal barrier dysfunction induced by indomethacin treatment affects the host response to intestinal microbiota in gluten-sensitized HLA-DQ8/HCD4 mice. Methodology/Principal Findings HLA-DQ8/HCD4 mice were sensitized with gluten, and gavaged with indomethacin plus gluten. Intestinal permeability was assessed by Ussing chamber; epithelial cell (EC) ultra-structure by electron microscopy; RNA expression of genes coding for junctional proteins by Q-real-time PCR; immune response by in-vitro antigen-specific T-cell proliferation and cytokine analysis by cytometric bead array; intestinal microbiota by fluorescence in situ hybridization and analysis of systemic antibodies against intestinal microbiota by surface staining of live bacteria with serum followed by FACS analysis. Indomethacin led to a more pronounced increase in intestinal permeability in gluten-sensitized mice. These changes were accompanied by severe EC damage, decreased E-cadherin RNA level, elevated IFN-? in splenocyte culture supernatant, and production of significant IgM antibody against intestinal microbiota. Conclusion Indomethacin potentiates barrier dysfunction and EC injury induced by gluten, affects systemic IFN-? production and the host response to intestinal microbiota antigens in HLA-DQ8/HCD4 mice. The results suggest that environmental factors that alter the intestinal barrier may predispose individuals to an increased susceptibility to gluten through a bystander immune activation to intestinal microbiota.
Natividad, Jane M.; Huang, Xianxi; Slack, Emma; Jury, Jennifer; Sanz, Yolanda; David, Chella; Denou, Emmanuel; Yang, Pinchang; Murray, Joseph
We describe the pathology of 17 patients with NSAID-associated stricturing and non-stricturing, erosive-ulcerative intestinal\\u000a pathology. Eight patients had stricturing lesions mainly localized in the caecal region and right-sided colon. All except\\u000a one patient who suffered exclusively from jejuno-ileal pathology had been treated with the slow-release form of diclofenac.\\u000a The lesions observed satisfied the macroscopic and microscopic criteria of diaphragm disease
F. Halter; A. Gut; C. Ruchti
Primary gastrointestinal lymphoma comprises a group of distinctive clinicopathological entities. They may be of B or T-cell type. Intestinal T-cell lymphomas are much less common and include the entity: lymphomas T enteropathy-associated T-cell lymphoma, the most common, and T-cell lymphoma without features of enteropathy. The morphologic and immunologic findings suggest that derived from mucosal T lymphocytes population. Clinically, the patients were usually males with constitutional symptoms and acute perforation and/or obstruction of the small bowel. Their prognosis are very poor and tumor are very aggressive. PMID:9595939
Remacha, B; Palau, A; Velicia, R; Caro-Patón, A; Ripollés, V
Salmonella enterica serotype Typhimurium causes acute inflammatory diarrhea in humans. Flagella contrib- ute to intestinal inflammation, but the mechanism remains unclear since most mutations abrogating pattern recognition of flagellin also prevent motility and reduce bacterial invasion. To determine the contribution of flagellin pattern recognition to the generation of innate immune responses, we compared in two animal models a nonmotile, but
Sebastian E. Winter; P. Thiennimitr; S.-P. Nuccio; T. Haneda; M. G. Winter; R. P. Wilson; J. M. Russell; T. Henry; Q. T. Tran; S. D. Lawhon; G. Gomez; C. L. Bevins; H. Russmann; D. M. Monack; L. G. Adams; A. J. Baumler
Obstruction of bile flow results in bacterial proliferation and mucosal injury in the small intestine that can lead to the translocation of bacteria across the epithelial barrier and systemic infection. These adverse effects of biliary obstruction can be inhibited by administration of bile acids. Here we show that the farnesoid X receptor (FXR), a nuclear receptor for bile acids, induces
Takeshi Inagaki; Antonio Moschetta; Youn-Kyoung Lee; Li Peng; Guixiang Zhao; Michael Downes; Ruth T. Yu; John M. Shelton; James A. Richardson; Joyce J. Repa; David J. Mangelsdorf; Steven A. Kliewer
To clarify the mechanism of toxification in animals contaminated with tetrodotoxin, the intestinal contents of the puffer Fugu vermicularis vermicularis were examined for bacterial flora in 1985. Twenty-six out of 33 strains belonged to the genus Vibrio. These bacteria were classified into Groups I to VII, based on biological and biochemical characters. High performance liquid chromatography and gas chromatography-mass spectrometry,
T. Noguchi; D. F. Hwang; O. Arakawa; H. Sugita; Y. Deguchi; Y. Shida; K. Hashimoto
The application of a multidisciplinary approach to study bacterial pathogenesis, along with the recent sequencing of entire microbial genomes have made possible discoveries that are changing the way scientists view the bacterium–host interaction. Today, research on the molecular basis of the pathogenesis of infectious diarrheal diseases of necessity transcends established boundaries between microbiology, cell biology, intestinal pathophysiology, and immunology. Novel
Alessio Fasano; James P Nataro
The alcohol-flush reaction occurs in Asians who inherit the mutantALDH2*2 allele that produces an inactive aldehyde dehydrogenase enzyme. In these individuals, high blood acetaldehyde levels are believed to be the cause of the unpleasant symptoms that follow drinking. We measured the alcohol elimination rates and intensity of flushing in Chinese subjects in whom the alcohol dehydrogenaseADH2 andALDH2 genotypes were determined.
Holly R. Thomasson; David W. Crabb; Howard J. Edenberg; Ting-Kai Li
The introduction of Candida albicans into cefoperazone-treated mice results in changes in bacterial community reassembly. Our objective was to use high-throughput sequencing to characterize at much greater depth the specific changes in the bacterial microbiome. The colonization of C. albicans significantly altered bacterial community reassembly that was evident at multiple taxonomic levels of resolution. There were marked changes in the levels of Bacteriodetes and Lactobacillaceae. Lachnospiraceae and Ruminococcaceae, the two most abundant bacterial families, did not change in relative proportions after antibiotics, but there were marked genera-level shifts within these two bacterial families. The microbiome shifts occurred in the absence of overt intestinal inflammation. Overall, these experiments demonstrate that the introduction of a single new microbe in numerically inferior numbers into the bacterial microbiome during a broad community disturbance has the potential to significantly alter the subsequent reassembly of the bacterial community as it recovers from that disturbance.
Erb Downward, John R.; Falkowski, Nicole R.; Mason, Katie L.; Muraglia, Ryan; Huffnagle, Gary B.
The animal and human intestinal mucosa secretes an assortment of compounds to establish a physical barrier between the host tissue and intestinal contents, a separation that is vital for health. Some pathogenic microorganisms as well as members of the commensal intestinal microbiota have been shown to be able to break down these secreted compounds. Our understanding of host-compound degradation by the commensal microbiota has been limited to knowledge about simplified model systems because of the difficulty in studying the complex intestinal ecosystem in vivo. In this study, we introduce an approach that overcomes previous technical limitations and allows us to observe which microbial cells in the intestine use host-derived compounds. We added stable isotope-labeled threonine i.v. to mice and combined fluorescence in situ hybridization with high-resolution secondary ion mass spectrometry imaging to characterize utilization of host proteins by individual bacterial cells. We show that two bacterial species, Bacteroides acidifaciens and Akkermansia muciniphila, are important host-protein foragers in vivo. Using gnotobiotic mice we show that microbiota composition determines the magnitude and pattern of foraging by these organisms, demonstrating that a complex microbiota is necessary in order for this niche to be fully exploited. These results underscore the importance of in vivo studies of intestinal microbiota, and the approach presented in this study will be a powerful tool to address many other key questions in animal and human microbiome research. PMID:23487774
Berry, David; Stecher, Bärbel; Schintlmeister, Arno; Reichert, Jochen; Brugiroux, Sandrine; Wild, Birgit; Wanek, Wolfgang; Richter, Andreas; Rauch, Isabella; Decker, Thomas; Loy, Alexander; Wagner, Michael
The effects of pathogenic organisms on host intestinal epithelial cells are vast. Innumerable signalling pathways are triggered leading ultimately to drastic changes in physiological functions. Here, the ways in which enteric bacterial pathogens utilise and impact on the three major physiological functions of the intestinal epithelium are discussed: alterations in the structure and function of the tight junction barrier, induction of fluid and electrolyte secretion, and activation of the inflammatory cascade. This field of investigation, which was virtually non-existent a decade ago, has now exploded, thus rapidly expanding our understanding of bacterial pathogenesis. Through increased delineation of the ways in which microbes alter host physiology, we simultaneous gain insight into the normal regulatory mechanisms of the intestinal epithelium.
Berkes, J; Viswanathan, V K; Savkovic, S D; Hecht, G
Antibiotics are recommended for use in the treatment of infectious diseases, but the side effects have not been thoroughly investigated, especially on the intestinal tract. Fluoroquinolones, macrolides and ?-lactams were tested the side effects on the intestinal microbflora of mice in this study. The similarity and sequence analysis of the dominant bands for different drug administration periods were carried out by denaturing gradient gel electrophoresis (DGGE) profiles. The total amount of 16S rRNA gene increased after drug administration, the bacterial composition and structure could be divided into different clusters for different drug administration periods distinctly. This study revealed a significant change of bacterial composition of microflora from intestinal tract as antibiotics were applied to tested mice. PMID:23455205
Xinli, Li; Dachang, Wu; Cuili, Zhang; Yi, Xin
Alcohol/water mixtures, such as those produced by fermentation of biomass material, are separated by extraction of alcohol with a solvent, comprising a higher aliphatic alcohol in major amount and an aliphatic hydrocarbon in minor amount, especially suited to such extraction and to subsequent removal. The solvent alcohol desirably has a branched chain, or the hydrocarbon an unsaturated bond, or both. Conventional distillation steps to concentrate alcohol and eliminate water are rendered unnecessary at a considerable reduction in heat energy requirement (usually met with fossil fuel). Optional addition of gasoline between the solvent extraction and solvent recovery steps not only aids the latter separation but produces alcohol already denatured for fuel use.
This Web site from the BBC provides a multi-faceted exploration of the science of alcohol. Visitors may browse eight detailed pages relating the science of alcohol production, how alcohol is absorbed and processed by the body, what happens when you've had too much, and much more. The clear yet detailed content of this site goes far to clear up alcohol-related misconceptions and misinformation. Other features include alcohol trivia, a quiz, movie and audio clips of alcohol-related BBC documentaries, links to other health Web sites for additional information, and a public message board.
A primary component of the intestinal mucous layer that functions as a barrier to luminal bacteria is mucin, a high-molecular-weight\\u000a glucoprotein. In addition, the mucous layer also contains other important elements such as phospholipids (PLs), which may\\u000a effect bacterial translocation (BTL). It has been reported that mucin inhibits Escherichia coli translocation; however, the effect of PLs on intestinal permeability is
N. Usui; C. J. Ray; R. A. Drongowski; A. G. Coran; C. M. Harmon
Proximal and distal small intestinal segments of the rat were perfused in situ at two different rates with isotonic solutions containing glucose in concentrations ranging from 25 to 600 mg/100 ml. Absorption was measured as glucose disappearance rate from the lumen. Glucose absorption had not previously been studied at intraluminal concentrations above and below blood glucose. Absorption was more rapid from the proximal segment. In both segments absorption was independent of perfusion rate and of whether glucose was analyzed by counting 14C or by the Somogyi method. The latter finding suggests that of the unidirectional fluxes, flux out of the bowel is much greater than flux into the bowel. In contrast to the findings in previous studies neither segment showed rate-limiting kinetics, and the Michaelis-Menten analysis was not applicable. The form of the curve depicting absorption rate in relation to concentration differed between the two segments. At the higher concentrations absorption rate continued to increase much more rapidly in the proximal than in the distal segment. The observations could not be explained by known mechanisms of glucose transport and illustrate the difficulties of achieving biochemically and physiologically meaningful in vivo studies of intestinal absorption.
Rider, Alan K.; Schedl, Harold P.; Nokes, George; Shining, Streeter
A case of endocervicosis of the small intestine incidentally found as a mass lesion dur ing a gastric bypass surgery is reported. No previous cases of intestinal endocervico sis have been reported in the literature. Int J Surg Pathol 10(1):65-67, 2002
Karl T. K. Chen
Primary intestinal lymphangiectasia (PIL) is a rare disorder characterized by dilated intestinal lacteals resulting in lymph leakage into the small bowel lumen and responsible for protein-losing enteropathy leading to lymphopenia, hypoalbuminemia and hypogammaglobulinemia. PIL is generally diagnosed before 3 years of age but may be diagnosed in older patients. Prevalence is unknown. The main symptom is predominantly bilateral lower limb
Stéphane Vignes; Jérôme Bellanger
Listeria monocytogenes is a food-borne bacterial pathogen that causes systemic infection by traversing the intestinal mucosa. Although MyD88-mediated signals are essential for defense against systemic L. monocytogenes infection, the role of Toll-like receptor and MyD88 signaling in intestinal immunity against this pathogen has not been defined. We show that clearance of L. monocytogenes from the lumen of the distal small intestine is impaired in MyD88?/? mice. The distal ileum of wild-type (wt) mice expresses high levels of RegIII?, which is a bactericidal lectin that is secreted into the bowel lumen, whereas RegIII? expression in MyD88?/? mice is nearly undetectable. In vivo depletion of RegIII? from the small intestine of wt mice diminishes killing of luminal L. monocytogenes, whereas reconstitution of MyD88-deficient mice with recombinant RegIII? enhances intestinal bacterial clearance. Experiments with bone marrow chimeric mice reveal that MyD88-mediated signals in nonhematopoietic cells induce RegIII? expression in the small intestine, thereby enhancing bacterial killing. Our findings support a model of MyD88-mediated epithelial conditioning that protects the intestinal mucosa against bacterial invasion by inducing RegIII?.
Brandl, Katharina; Plitas, George; Schnabl, Bernd; DeMatteo, Ronald P.; Pamer, Eric G.
The composition of the oral microbiota from 10 individuals with healthy oral tissues was determined using culture-independent techniques. From each individual, 26 specimens, each from different oral sites at a single point in time, were collected and pooled. An eleventh pool was constructed using portions of the subgingival specimens from all 10 individuals. The 16S rRNA gene was amplified using broad-range bacterial primers, and clone libraries from the individual and subgingival pools were constructed. From a total of 11 368 high-quality, non-chimeric, near full-length sequences, 247 species-level phylotypes (using a 99% sequence identity threshold) and 9 bacteria phyla were identified. At least 15 bacterial genera were conserved among all 10 individuals, with significant interindividual differences at the species and strain level. Comparisons of these oral bacterial sequences to near full-length sequences found previously in the large intestines and feces of other healthy individuals suggest that the mouth and intestinal tract harbor distinct sets of bacteria. Co-occurrence analysis demonstrated significant segregation of taxa when community membership was examined at the level of genus, but not at the level of species, suggesting that ecologically-significant, competitive interactions are more apparent at a broader taxonomic level than species. This study is one of the more comprehensive, high-resolution analyses of bacterial diversity within the healthy human mouth to date, and highlights the value of tools from macroecology for enhancing our understanding of bacterial ecology in human health.
Bik, Elisabeth M.; Long, Clara Davis; Armitage, Gary C.; Loomer, Peter; Emerson, Joanne; Mongodin, Emmanuel F.; Nelson, Karen E.; Gill, Steven R.; Fraser-Liggett, Claire M.; Relman, David A.
A study of the effects of abrupt weaning on the very young pig showed that the samll intestine undergoes an acute inflammatory response and a reduction in plasma cell population by weaning day +7 or +8, in the absence of severe scours and abnormal proliferation by intestinal coliform bacteria. It is suggested that these changes may be common progenitors of nutritional and bacterial scours, and that they are due in part to increased metabolic activity of the "normal" microflora. PMID:951529
We have investigated the presence, duration, and clinical significance of granulocyte accumulation, using indium-111 granulocyte scanning, in patients following uncomplicated intestinal anastomosis. Eight patients underwent intestinal resection and anastomosis (right hemicolectomy, 5; sigmoid colectomy, 2; ileal resection, 1) for carcinoma, angiodysplasia, or perforation. All patients had an uneventful postoperative course, with no evidence of any leakage or infection. Indium-111 granulocyte scan and abdominal ultrasound were performed 7-20 days (12 +/- 4.7 means +/- SD) following surgery. Indium-111 granulocyte scan showed the presence of labeled granulocytes at the site of anastomosis in all patients. In three of eight, cells subsequently passed into the lumen of the bowel. In contrast, granulocytes were not visualized along the abdominal incision. Thus, in contrast to skin wounds, granulocytes continue migrating into the intestinal wall in areas of anastomosis for at least up to 20 days following surgical trauma. They may play a significant role both in healing the anastomosis and in preventing systemic bacterial infection. Moreover, indium-111 granulocyte scans following intestinal surgery should be interpreted with care, and the presence of labeled granulocytes around anastomoses does not necessarily indicate abscess formation.
Keshavarzian, A.; Gibson, R.; Guest, J.; Spencer, J.; Lavender, J.P.; Hodgson, H.J.
Human intestinal epithelial cell monolayers were inoculated with cultures of Mycobacterium avium serotype 2, 8, or 10 that were viable, autoclaved, Formalin killed, exposed to UV light, or suspended in anti-M. avium serotype 2 serum. The effects of four reagents known to block phagocytosis or endocytosis (cytochalasin B, dibutyryl cyclic adenosine monophosphate, iodoacetate, and 2,4-dinitrophenol) on the bacteria-cell interaction were also studied. The maximum uptake of pathogenic M. avium by human intestinal epithelial cells occurred after 2 to 3 h of incubation. Serotype 2 was taken up in greater quantity than serotype 8 or 10. Saprophytic mycobacteria did not attach to or penetrate the host cells. The data showed that viable mycobacteria are ingested by host cells, whereas dead organisms are not. Components of the bacterial cells are partially, but not solely, responsible for the phagocytosis of M. avium serotype 2 by human intestinal epithelial cells. Furthermore, uptake of M. avium by human intestinal epithelial cells was suppressed by reagents which inhibit uptake by known phagocytic cells, suggesting that the mechanism of uptake is an endocytic process induced by virulent mycobacteria.
Mapother, M E; Songer, J G
The intestinal mucosa faces the challenge of regulating the balance between immune tolerance towards commensal bacteria, environmental stimuli and food antigens on the one hand, and induction of efficient immune responses against invading pathogens on the other hand. This regulatory task is of critical importance to prevent inappropriate immune activation that may otherwise lead to chronic inflammation, tissue disruption and organ dysfunction. The most striking example for the efficacy of the adaptive nature of the intestinal mucosa is birth. Whereas the body surfaces are protected from environmental and microbial exposure during fetal life, bacterial colonization and contact with potent immunostimulatory substances start immediately after birth. In the present review, we summarize the current knowledge on the mechanisms underlying the transition of the intestinal mucosa during the neonatal period leading to the establishment of a stable, life-long host-microbial homeostasis. The environmental exposure and microbial colonization during the neonatal period, and also the influence of maternal milk on the immune protection of the mucosa and the role of antimicrobial peptides, are described. We further highlight the molecular mechanisms of innate immune tolerance in neonatal intestinal epithelium. Finally, we link the described immunoregulatory mechanisms to the increased susceptibility to inflammatory and infectious diseases during the neonatal period. PMID:21952827
Stockinger, Silvia; Hornef, Mathias W; Chassin, Cécilia
|This guide reviews audiovisual materials currently available on alcohol abuse and alcoholism. An alphabetical index of audiovisual materials is followed by synopses of the indexed materials. Information about the intended audience, price, rental fee, and distributor is included. This guide also provides a list of publications related to media…
National Clearinghouse for Alcohol Information (DHHS), Rockville, MD.
This study investigates the effects of alcohol advertising on adolescent alcohol consumption. The theory of an industry response function and evidence from prior studies indicate the importance of maximizing the variance in advertising measures. Monitoring the Future (MTF) and National Longitudinal Survey of Youth 1997 (NLSY97) data are augmented with alcohol advertising, originating on the market level, for five media. The large sample of the MTF allows estimation of race and gender-specific models. The longitudinal nature of the NLSY97 allows controls for unobserved heterogeneity with state-level and individual fixed effects. Price and advertising effects are generally larger for females relative to males. Controls for individual heterogeneity yield larger advertising effects, implying that the MTF results may understate the effects of alcohol advertising. Results from the NLSY97 suggest that a 28% reduction in alcohol advertising would reduce adolescent monthly alcohol participation from 25% to between 24 and 21%. For binge participation, the reduction would be from 12% to between 11 and 8%. The past month price-participation elasticity is estimated at -0.26, consistent with prior studies. The results show that reduction of alcohol advertising can produce a modest decline in adolescent alcohol consumption, though effects may vary by race and gender. PMID:16475245
Saffer, Henry; Dave, Dhaval
The purpose of this paper is to empirically estimate the effects of alcohol advertising on adolescent alcohol consumption. The theory of brand capital is used to explain the effects of advertising on consumption. The industry response function and the evidence from prior studies indicate that the empirical strategy should maximize the variance in the advertising data. The approach in this
Henry Saffer; Dhaval Dave
It is estimated that two million African-Americans suffer directly and indirectly from alcoholism and its related problems. Yet, because of their cultural background, African-American alcoholics do not readily accept that alcoholism is a disease. This study explores how African-American alcoholics modify the steps and traditions of AA to affiliate with the organization. Data was collected from intensive and semi-structured interviews
Alcohol/water mixtures, such as those produced by fermentation of biomass material, are separated by extraction of alcohol with a solvent especially suited to such extraction and to subsequent removal. Conventional distillation steps to concentrate alcohol and eliminate water are rendered unnecessary at a considerable reduction in heat energy requirement (Usually met with fossil fuel). Addition of gasoline between the solvent extraction and solvent recovery steps not only aids the latter separation but produces alcohol already denatured for fuel use.
A cohort of alcoholics who underwent a medico-legal autopsy during a 5-year period was compared with non-alcoholic controls who did not differ from the alcoholics in selection criteria. The degree of atherosclerosis in the coronary arteries and the aorta was examined. Alcoholic men and old women had a significantly lower degree of atherosclerosis in the coronary arteries, while the opposite
Jørgen L. Thomsen
Alcohol production rate decreases as the concentration of bacterial contaminants increases. In complex medium, such as beet molasses, an alternative mechanism can be used by homofermentative lactic bacteria (Lactobacillus casei). Lactic acid and associated products, especially acetic acid, are liberated into the medium. The inhibition induced by these metabolites was reinforced by the presence of viable lactobacilli.
J. J. Essia Ngang; F. Letourneau; E. Wolniewicz; P. Villa
|Maintains that minority youth who use (or abuse) alcohol in American society deal with using alcohol, being minority, and being young, three dimensions viewed by society with mixed, sometimes hostile and/or fearful reactions. Suggests that examining alcoholism among minority youth involves coming to grips with poverty, education, income, and life…
Wright, Roosevelt, Jr.; Watts, Thomas D.
|States that adolescents begin to drink alcohol at ever younger ages, partly because they receive mixed messages from the media. Argues that drug prevention groups must project accurate, consistent, and effective messages about alcohol for youth and that schools must provide education about the specific health risks of alcohol beginning in grade…
Roth, Paula; Friedman, Lora
Evidence suggests that alcohol affects brain function by interacting with multiple neurotransmitter systems, thereby disrupting the delicate balance between inhibitory and excitatory neurotransmitters. Short-term alcohol exposure tilts this balance in favor of inhibitory influences. After long-term alcohol exposure, however, the brain attempts to compensate by tilting the balance back toward equilibrium. These neurological changes occur as the development of tolerance
C. FERNANDO VALENZUELA
Concern about how much television alcohol advertising reaches underage youth and how the advertising influences their attitudes and decisions about alcohol use has been widespread for many years. Lacking in the policy debate has been solid, reliable information about the extent of youth exposure to television alcohol advertising. To address this…
|Interprets data obtained through surveys concerning Soviet college students' alcohol consumption. Examines onset of drinking, frequency of drinking and inebriation, peer influence, gender differences, and students' self-assessments of alcohol use. Considers alcohol's habituating effects and consequent impact on individual development. (CH)|
Levin, Boris Mikhailovich; Levin, Mikhail Borisovich
Background: Maternal alcohol use during pregnancy leads to fetal alcohol spectrum disorder (FASD) in their children. FASD is characterized by typical facial features, growth retardation, intellectual dysfunction and behavioral problems. Justification: Alcohol is neurotoxic to the brain during the developmental stage. Behavioral problems in children with FASD start at an early age and progress to adulthood. It is an important
RAGHAVENDRA BHEEMAPPA N AYAK; PRATIMA MURTHY
Conservative estimates of sexual assault prevalence suggest that 25 percent of American women have experienced sexual assault, including rape. Approximately one-half of those cases involve alcohol consumption by the perpetrator, victim, or both. Alcohol contributes to sexual assault through multiple pathways, often exacerbating existing risk factors. Beliefs about alcohol's effects on sexual and aggressive behavior, stereotypes about drinking women, and
Antonia Abbey; Tina Zawacki; Philip O. Buck; A. Monique Clinton; Pam McAuslan
|A path analytic model for Hispanic alcoholics relating socioclinical prognostic variables to outcome following treatment in a therapeutic community differs markedly from that fitted to Anglo alcoholics. The differential relationship of education to alcoholism severity and outcome was noted specifically as reflecting different racial-ethnic paths…
Costello, Raymond M.
Alcohol dependence and alcohol abuse or harmful use cause substantial morbidity and mortality. Alcohol-use disorders are associated with depressive episodes, severe anxiety, insomnia, suicide, and abuse of other drugs. Continued heavy alcohol use also shortens the onset of heart disease, stroke, cancers, and liver cirrhosis, by affecting the cardiovascular, gastrointestinal, and immune systems. Heavy drinking can also cause mild anterograde amnesias, temporary cognitive deficits, sleep problems, and peripheral neuropathy; cause gastrointestinal problems; decrease bone density and production of blood cells; and cause fetal alcohol syndrome. Alcohol-use disorders complicate assessment and treatment of other medical and psychiatric problems. Standard criteria for alcohol dependence-the more severe disorder-can be used to reliably identify people for whom drinking causes major physiological consequences and persistent impairment of quality of life and ability to function. Clinicians should routinely screen for alcohol disorders, using clinical interviews, questionnaires, blood tests, or a combination of these methods. Causes include environmental factors and specific genes that affect the risk of alcohol-use disorders, including genes for enzymes that metabolise alcohol, such as alcohol dehydrogenase and aldehyde dehydrogenase; those associated with disinhibition; and those that confer a low sensitivity to alcohol. Treatment can include motivational interviewing to help people to evaluate their situations, brief interventions to facilitate more healthy behaviours, detoxification to address withdrawal symptoms, cognitive-behavioural therapies to avoid relapses, and judicious use of drugs to diminish cravings or discourage relapses. PMID:19168210
Schuckit, Marc A
|Concern about how much television alcohol advertising reaches underage youth and how the advertising influences their attitudes and decisions about alcohol use has been widespread for many years. Lacking in the policy debate has been solid, reliable information about the extent of youth exposure to television alcohol advertising. To address this…
There is no question that excessive alcohol use during pregnancy can harm the fetus. However, the available scientific evidence does not support the contention that absolute abstinence from alcohol is necessary to protect the unborn child. Pregnant women should be advised to limit alcohol intake, but a call for absolute abstinence is not justified, since such advice can have negative
David B. Roll; Terrence Smith; Elizabeth M. Whelan
Alcohol is the most common cause of liver injury in the developed world. In 1999, alcoholic liver disease was the most common indication for transplantation in UK and Europe. A regional centre in the UK sees, on average, more than 400 patients with alcoholic liver disease each year. As highlighted in the recent Chief Medical Officer's report (2002), deaths from
Chris P Day
The rationale behind alcohol availability controls as a policy measure is relatively simple - by making access to beverage alcohol more difficult, consumption will be decreased and with it the incidence of problems. The public health perspective, not necessarily concerned with economic efficiency or profitability, sees curbing alcohol consumption as a means of preventing a range of social and health
Lucia Antalova; Marjana Martini
|Reviews the role of biological factors in the risk for alcoholism. Notes the importance of the definition of primary alcoholism and highlights data indicating that this disorder is genetically influenced. In studies of men at high risk for the future development of alcoholism, vulnerability shows up in reactions to ethanol brain wave amplitude…
Schuckit, Marc A.
Background: Current heart failure (HF) guidelines note that alcohol use should be discouraged or restricted in patients with HF resulting from left ventricular systolic dysfunction. Existing knowledge is limited in the area of HF and alcohol. Methods and Results: The purpose of this article is to review the evidence regarding the acute and long-term use of alcohol in the setting
Mariann R. Piano
In this research study, a system to support medical analysis of intestinal contractions by processing WCE images is presented. Small intestine contractions are among the motility patterns which reveal many gastrointestinal disorders, such as functional dyspepsia, paralytic ileus, irritable bowel syndrome, bacterial overgrowth. The images have been obtained using the Wireless Capsule Endoscopy (WCE) technique, a patented, video colorimaging disposable capsule. Manual annotation of contractions is an elaborating task, since the recording device of the capsule stores about 50,000 images and contractions might represent only the 1% of the whole video. In this paper we propose the use of Local Binary Pattern (LBP) combined with the powerful textons statistics to find the frames of the video related to contractions. We achieve a sensitivity of about 80% and a specificity of about 99%. The achieved high detection accuracy of the proposed system has provided thus an indication that such intelligent schemes could be used as a supplementary diagnostic tool in endoscopy.
Gallo, Giovanni; Granata, Eliana
As opposed to other invasive pathogens that reside into host cells in a parasitic mode, Shigella, the causative agent of bacillary dysentery, invades the colonic mucosa but does not penetrate further to survive into deeper tissues. Instead, Shigella invades, replicates, and disseminates within the colonic mucosa. Bacterial invasion and spreading in intestinal epithelium lead to the elicitation of inflammatory responses responsible for the tissue destruction and shedding in the environment for further infection of other hosts. In this article, we highlight specific features of the Shigella arsenal of virulence determinants injected by a type III secretion apparatus (T3SA) that point to the targeting of intestinal epithelial cells as a discrete route of invasion during the initial event of the infectious process. PMID:24086068
Carayol, Nathalie; Tran Van Nhieu, Guy
Commensal bacteria inhabit mucosal and epidermal surfaces in mice and humans, and have effects on metabolic and immune pathways in their hosts. Recent studies indicate that the commensal microbiota can be manipulated to prevent and even to cure infections that are caused by pathogenic bacteria, particularly pathogens that are broadly resistant to antibiotics, such as vancomycin-resistant Enterococcus faecium, Gram-negative Enterobacteriaceae and Clostridium difficile. In this Review, we discuss how immune- mediated colonization resistance against antibiotic-resistant intestinal pathogens is influenced by the composition of the commensal microbiota. We also review recent advances characterizing the ability of different commensal bacterial families, genera and species to restore colonization resistance to intestinal pathogens in antibiotic-treated hosts. PMID:24096337
Buffie, Charlie G; Pamer, Eric G
Background\\/Aims\\/Methods: Spontaneous bacterial peritonitis (SBP) is a frequent complication of advanced liver disease and in high-risk patients, it is associated with a mean (per episode) mortality of 29% and a mean 1-year mortality of 82%. The 1-year recurrence rate of SBP can be as high as 30–70%. Selective intestinal decontamination with antibiotic prophylaxis has been shown to significantly reduce the
Zobair M. Younossi; John G. McHutchison; Ted G. Ganiats
Balance among the complex interactions of the gut microbial community is important for intestinal health. Probiotic bacteria can improve bacterial balance and have been used to treat gastrointestinal diseases. Neonatal necrotizing enterocolitis (NEC) is a life-threatening inflammatory bowel disorder primarily affecting premature infants. NEC is associated with extensive inflammatory NF-?B signaling activation as well as intestinal barrier disruption. Clinical studies have shown that probiotic administration may protect against NEC, however there are safety concerns associated with the ingestion of large bacterial loads in preterm infants. Bacteria-free conditioned media (CM) from certain probiotic organisms have been shown to retain bioactivity including anti-inflammatory and cytoprotective properties without the risks of live organisms. We hypothesized that the CM from Lactobacillus acidophilus (La), Bifidobacterium infantis (Bi), and Lactobacillus plantarum (Lp), used separately or together would protect against NEC. A rodent model with intestinal injury similar to NEC was used to study the effect of CM from Lp, La/Bi, and La/Bi/Lp on the pathophysiology of NEC. All the CM suppressed NF-?B activation via preserved I?B? expression and this protected I?B? was associate