BACKGROUNDSmall intestinal bacterial overgrowth may contribute to the development of non-alcoholic steatohepatitis, perhaps by increasing intestinal permeability and promoting the absorption of endotoxin or other enteric bacterial products.AIMSTo investigate the prevalence of small intestinal bacterial overgrowth, increased intestinal permeability, elevated endotoxin, and tumour necrosis factor ? (TNF-?) levels in patients with non-alcoholic steatohepatitis and in control subjects.PATIENTS AND METHODSTwenty two
A J Wigg; I C Roberts-Thomson; R B Dymock; P J McCarthy; R H Grose; A G Cummins
Background—Small intestinal bacterial overgrowth may contribute to the devel- opment of non-alcoholic steatohepatitis, perhaps by increasing intestinal perme- ability and promoting the absorption of endotoxin or other enteric bacterial prod- ucts. Aims—To investigate the prevalence of small intestinal bacterial overgrowth, in- creased intestinal permeability, elevated endotoxin, and tumour necrosis factor Æ (TNF-Æ) levels in patients with non- alcoholic steatohepatitis and
A J Wigg; I C Roberts-Thomson; R B Dymock; P J McCarthy; R H Grose; A G Cummins
Small intestinal bacterial overgrowth (SIBO) syndrome is characterized in its florid form by diarrhoea and weight loss. The most common underlying factors are dysmotility, small intestinal obstruction, blind or afferent loops. Small intestinal bacterial overgrowth can be diagnosed by: 1) culture of jejunum aspirate for bacterial counts, 2) 14C-D-xylose breath testing, 3) non-invasive hydrogen breath testing using glucose or lactulose or 4) 14C-glycocholic acid breath testing. The treatment usually consists of the eradication of bacterial overgrowth with repeated course of antimicrobials, correction of associated nutritional deficiencies and, when possible, correction of the underlying predisposing conditions. PMID:18609165
Rana, S V; Bhardwaj, S B
Small intestinal bacterial overgrowth (SIBO), defined as excessive bacteria in the small intestine, remains a poorly understood disease. Initially thought to occur in only a small number of patients, it is now apparent that this disorder is more prevalent than previously thought. Patients with SIBO vary in presentation, from being only mildly symptomatic to suffering from chronic diarrhea, weight loss, and malabsorption. A number of diagnostic tests are currently available, although the optimal treatment regimen remains elusive. Recently there has been renewed interest in SIBO and its putative association with irritable bowel syndrome. In this comprehensive review, we will discuss the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of SIBO.
Dukowicz, Andrew C.; Levine, Gary M.
It is generally accepted that activation of the innate immune system and increased release of pro-inflammatory cytokines and other mediators plays an important role in the development of alcoholic liver disease (ALD). The mechanisms involved in the ethanol-induced activation of monocytes/macrophages (including Kupffer cells) are however, still a matter of debate. The brief review will summarize the published data from the literature on the two main pathomechanisms discussed until now: I) Gut-derived bacterial toxins, specially endotoxin; and II) metabolic changes induced by alcohol oxidation (independent of mechanism I). For pathomechanism I, clear evidence has been published from numerous groups: Alcohol induces mucosal injury in the upper gastrointestinal tract and leads to marked increase in the permeability of the gut mucosa to macromolecules such as endotoxin. The resulting endotoxemia then leads to activation of Kupffer cells and other macrophages. The increased release of pro-inflammatory mediators (e.g., TNF-alpha, Il-1, reacting oxygen species) and infiltration of other inflammatory cells (e.g., neutrophils) finally causes liver damage. Regarding the second pathomechanism it has repeatedly been argued that the metabolic alterations which are induced by chronic administration of ethanol to rats or mice might increase the sensitivity of monocytes/macrophages to secrete TNF-alpha and other pro-inflammatory mediators thereby increasing the susceptibility to ethanol-induced liver injury. However, in all feeding experiments the effect of ethanol on intestinal permeability and enhanced translocation of bacterial toxins (endotoxin) is likely to occur (or at least cannot be excluded). The latter holds true also for experiments using isolated macrophages/Kupffer cells from ethanol fed animals. Therefore, to clarify whether or not alterations related to ethanol metabolism ("direct" effects of ethanol) contribute to the activation of the innate immune system studies using germ-free animals are needed to exclude the "indirect" effect of ethanol via gut-derived bacterial toxins. PMID:16344604
Bode, Christiane; Bode, J Christian
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
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 Castaño; L. Martín Ramos; Maria J. López Arias; F. Ledesma; F. Pons Romero
Small intestinal bacterial overgrowth (SIBO) is a clinical condition characterized by a malabsorption syndrome due to an increase in microorganisms within the small intestine. The main mechanisms restricting bacterial colonization in the upper gut are the gastric acid barrier, mucosal and systemic immunity and intestinal clearance. When these mechanisms fail, bacterial overgrowth develops. Diarrhea, steatorrhea, chronic abdominal pain, bloating and
Antonio Gasbarrini; Maurizio Gabrielli; Emidio Scarpellini; Andrea Lupascu; Veronica Ojetti; Giovanni Gasbarrini
Small intestinal bacterial overgrowth (SIBO) is a clinical condition characterized by a malabsorption syndrome due to an increase in microorganisms within the small intestine. The main mechanisms restricting bacterial colonization in the upper gut are the gastric acid barrier, mucosal and systemic immunity and intestinal clearance. When these mechanisms fail, bacterial overgrowth develops. Diarrhea, steatorrhea, chronic abdominal pain, bloating and flatulence are common symptoms and are similar to those observed in irritable bowel syndrome. Breath tests (glucose and/or lactulose breath tests) have been proposed as a sensitive and simple tool for the diagnosis of bacterial overgrowth, being non-invasive and inexpensive compared to the gold standard represented by the culture of intestinal aspirates. Antibiotic therapy is the cornerstone of SIBO treatment. Current SIBO treatment is based on empirical courses of broad-spectrum antibiotics since few controlled studies concerning the choice and duration of antibiotic therapy are available at present. PMID:17827947
Gasbarrini, Antonio; Lauritano, Ernesto Cristiano; Gabrielli, Maurizio; Scarpellini, Emidio; Lupascu, Andrea; Ojetti, Veronica; Gasbarrini, Giovanni
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
Despite two centuries of reports linking alcohol consumption with enhanced susceptibility to bacterial infections and in particular gut-derived bacteria, there have been no studies or model systems to assess the impact of long-term alcohol exposure on the ability of the epithelial barrier to withstand bacterial infection. It is well established that acute alcohol exposure leads to reduction in tight and adherens junctions, which in turn leads to increases in epithelial cellular permeability to bacterial products, leading to endotoxemia and a variety of deleterious effects in both rodents and human. We hypothesized that reduced fortification at junctional structures should also reduce the epithelial barrier’s capacity to maintain its integrity in the face of bacterial challenge thus rendering epithelial cells more vulnerable to infection. In this study, we established a cell-culture based model system for long-term alcohol exposure to assess the impact of chronic alcohol exposure on the ability of Caco-2 intestinal epithelial cells to withstand infection when facing pathogenic bacteria under the intact or wounded conditions. We report that daily treatment with 0.2% ethanol for two months rendered Caco-2 cells far more susceptible to wound damage and cytotoxicity caused by most but not all bacterial pathogens tested in our studies. Consistent with acute alcohol exposure, long-term ethanol exposure also adversely impacted tight junction structures, but in contrast, it did not affect the adherens junction. Finally, alcohol-treated cells partially regained their ability to withstand infection when ethanol treatment was ceased for two weeks, indicating that alcohol’s deleterious effects on cells may be reversible.
Wood, Stephen; Pithadia, Ravi; Rehman, Tooba; Zhang, Lijuan; Plichta, Jennifer; Radek, Katherine A.; Forsyth, Christopher; Keshavarzian, Ali; Shafikhani, Sasha H.
Small intestinal bacterial overgrowth is common in in- testinal failure. Its occurrence relates to alterations in intestinal anatomy, motility, and gastric acid secretion. Its presence may contribute to symptoms, mucosal in- jury, and malnutrition. Relationships between bacterial overgrowth and systemic sepsis are of potential impor- tance in the intestinal failure patient because the direct translocation of bacteria across the intestinal
EAMONN M. M. QUIGLEY; RODRIGO QUERA
Background Bacterial gastroenteritis causes morbidity and mortality in humans worldwide. Murine Citrobacter rodentium infection is a model for gastroenteritis caused by the human pathogens enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. Mucin glycoproteins are the main component of the first barrier that bacteria encounter in the intestinal tract. Methodology/Principal Findings Using Immunohistochemistry, we investigated intestinal expression of mucins (Alcian blue/PAS, Muc1, Muc2, Muc4, Muc5AC, Muc13 and Muc3/17) in healthy and C. rodentium infected mice. The majority of the C. rodentium infected mice developed systemic infection and colitis in the mid and distal colon by day 12. C. rodentium bound to the major secreted mucin, Muc2, in vitro, and high numbers of bacteria were found in secreted MUC2 in infected animals in vivo, indicating that mucins may limit bacterial access to the epithelial surface. In the small intestine, caecum and proximal colon, the mucin expression was similar in infected and non-infected animals. In the distal colonic epithelium, all secreted and cell surface mucins decreased with the exception of the Muc1 cell surface mucin which increased after infection (p<0.05). Similarly, during human infection Salmonella St Paul, Campylobacter jejuni and Clostridium difficile induced MUC1 in the colon. Conclusion Major changes in both the cell-surface and secreted mucins occur in response to intestinal infection.
Linden, Sara K.; Florin, Timothy H. J.; McGuckin, Michael A.
An important approach to the major health problem of bacterial infection in young children has been to examine bacterial toxin binding to microvillus membrane receptors, the signal transduction produced by that interaction and the mechanisms of fluid secretion in the developing intestine as a basis for toxigenic diarrhea in the infant population. These studies indicate that receptor binding and effector responses may be subjected to developmental regulation. This regulation process of toxin interaction with the developing intestine may have an enhanced or harmful effect or, under some circumstances, may have a beneficial effect and be protective to the vulnerable child. Specific mechanisms for the developmental control of receptor expression may involve the regulation of individual glycosyltransferases responsible for the addition of receptor sugar sequences to glycolipids and/or glycoproteins, presumably at the transcriptional level. Furthermore, although highly speculative at this point, the differential expression of signal transducers (e.g., guanine nucleotide-regulatory proteins or G proteins) and ion transporters (e.g., Na+,K(+)-stimulated adenosine triphosphatase, the Cl- channels, etc.) during development may also alter the neonatal host's responsiveness. Therefore, the developmental control of microvillus membrane receptors, signal transduction mechanisms, and ion transport systems in the gastro-intestinal tract may in part contribute to the altered host sensitivity in toxigenic diarrhea of infancy. PMID:8382647
Chu, S H; Walker, W A
Hemolysis of blood agar is broadly used as a diagnostic tool for identifying and studying pathogenic microorganisms. We have\\u000a recently shown that alcohol vapors can confer hemolytic properties on otherwise nonhemolytic fungi (microbial alcohol-conferred\\u000a hemolysis; MACH). Until now, this phenomenon has been found in various yeast strains and other fungi, but only in a few bacterial\\u000a species (e.g., staphylococci). In
Natali Shirron; Moshe Korem; Amir Shuster; Alicia Leikin-Frenkel; Mel Rosenberg
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
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. PMID:23087650
Hartmann, Phillipp; Chen, Wei-Chung; Schnabl, Bernd
Host inflammatory responses against pathogenic organisms can be abrogated by commensals; however, the molecular mechanisms by which pathogenesis is prevented are still poorly understood. Previous studies demonstrated that administration of a single dose of Bacillus subtilis prevented disease and inflammation by the enteric mouse pathogen Citrobacter rodentium, which causes disease similar to the human pathogen enteropathogenic Escherichia coli. No protection was observed when an exopolysaccharide (EPS)-deficient mutant of B. subtilis was used, suggesting that EPS are the protective factor. In this study, we isolated and characterized EPS and showed that they also prevent C. rodentium-associated intestinal disease after a single injection. Protection is TLR4 dependent because EPS-treated TLR4 knockout mice developed disease. Furthermore, protection could be conveyed to wild-type mice by adoptive transfer of macrophage-rich peritoneal cells from EPS-treated mice. We found that EPS specifically bind peritoneal macrophages, and because mice lacking MyD88 signaling in myeloid cells were not protected by EPS, we conclude that bacterial EPS prevent colitis in a TLR4-dependent manner that requires myeloid cells. These studies provide a simple means of preventing intestinal inflammation caused by enteric pathogens. PMID:24740503
Jones, Sara E; Paynich, Mallory L; Kearns, Daniel B; Knight, Katherine L
A bacterial isolate identified as Xanthomonas sp. proved to be ligninolytic due to its ability to degrade 14C-labeled dehydropolymers of coniferyl alcohol (DHP) and [14C]lignocellulose complexes from corn plants (Zea mays). Several parameters of ligninolysis were evaluated and it was shown that resting cells degrade DHP as sole carbon source. Enhancement of DHP degradation in the presence of ferulic acid
Hartmut W. Kern
Background The liver is the first line of defence against continuously occurring influx of microbial-derived products and bacteria from the gut. Intestinal bacteria have been implicated in the pathogenesis of alcoholic liver cirrhosis. Escape of intestinal bacteria into the ascites is involved in the pathogenesis of spontaneous bacterial peritonitis, which is a common complication of liver cirrhosis. The association between faecal bacterial populations and alcoholic liver cirrhosis has not been resolved. Methods Relative ratios of major commensal bacterial communities (Bacteroides spp., Bifidobacterium spp., Clostridium leptum group, Enterobactericaea and Lactobacillus spp.) were determined in faecal samples from post mortem examinations performed on 42 males, including cirrhotic alcoholics (n?=?13), non-cirrhotic alcoholics (n?=?15), non-alcoholic controls (n?=?14) and in 7 healthy male volunteers using real-time quantitative PCR (RT-qPCR). Translocation of bacteria into liver in the autopsy cases and into the ascites of 12 volunteers with liver cirrhosis was also studied with RT-qPCR. CD14 immunostaining was performed for the autopsy liver samples. Results Relative ratios of faecal bacteria in autopsy controls were comparable to those of healthy volunteers. Cirrhotics had in median 27 times more bacterial DNA of Enterobactericaea in faeces compared to the healthy volunteers (p?=?0.011). Enterobactericaea were also the most common bacteria translocated into cirrhotic liver, although there were no statistically significant differences between the study groups. Of the ascites samples from the volunteers with liver cirrhosis, 50% contained bacterial DNA from Enterobactericaea, Clostridium leptum group or Lactobacillus spp.. The total bacterial DNA in autopsy liver was associated with the percentage of CD14 expression (p?=?0.045). CD14 expression percentage in cirrhotics was significantly higher than in the autopsy controls (p?=?0.004). Conclusions Our results suggest that translocation of intestinal bacteria into liver may be involved as a one factor in the pathogenesis of alcoholic liver cirrhosis.
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
Accumulating evidence suggests that hyperproliferating intestinal stem cells (SCs) and progenitors drive cancer initiation, maintenance, and metastasis. In addition, chronic inflammation and infection have been increasingly recognized for their roles in cancer. Nevertheless, the mechanisms by which bacterial infections can initiate SC-mediated tumorigenesis remain elusive. Using a Drosophila model of gut pathogenesis, we show that intestinal infection with Pseudomonas aeruginosa, a human opportunistic bacterial pathogen, activates the c-Jun N-terminal kinase (JNK) pathway, a hallmark of the host stress response. This, in turn, causes apoptosis of enterocytes, the largest class of differentiated intestinal cells, and promotes a dramatic proliferation of SCs and progenitors that serves as a homeostatic compensatory mechanism to replenish the apoptotic enterocytes. However, we find that this homeostatic mechanism can lead to massive over-proliferation of intestinal cells when infection occurs in animals with a latent oncogenic form of the Ras1 oncogene. The affected intestines develop excess layers of cells with altered apicobasal polarity reminiscent of dysplasia, suggesting that infection can directly synergize with the genetic background in predisposed individuals to initiate SC-mediated tumorigenesis. Our results provide a framework for the study of intestinal bacterial infections and their effects on undifferentiated and mature enteric epithelial cells in the initial stages of intestinal cancer. Assessment of progenitor cell responses to pathogenic intestinal bacteria could provide a measure of predisposition for apoptotic enterocyte-assisted intestinal dysplasias in humans. PMID:19934041
Apidianakis, Yiorgos; Pitsouli, Chrysoula; Perrimon, Norbert; Rahme, Laurence
The circadian clock orchestrates temporal patterns of physiology and behavior relative to the environmental light:dark cycle by generating and organizing transcriptional and biochemical rhythms in cells and tissues throughout the body. Circadian clock genes have been shown to regulate the physiology and function of the gastrointestinal tract. Disruption of the intestinal epithelial barrier enables the translocation of proinflammatory bacterial products, such as endotoxin, across the intestinal wall and into systemic circulation; a process that has been linked to pathologic inflammatory states associated with metabolic, hepatic, cardiovascular and neurodegenerative diseases – many of which are commonly reported in shift workers. Here we report, for the first time, that circadian disorganization, using independent genetic and environmental strategies, increases permeability of the intestinal epithelial barrier (i.e., gut leakiness) in mice. Utilizing chronic alcohol consumption as a well-established model of induced intestinal hyperpermeability, we also found that both genetic and environmental circadian disruption promote alcohol-induced gut leakiness, endotoxemia and steatohepatitis, possibly through a mechanism involving the tight junction protein occludin. Circadian organization thus appears critical for the maintenance of intestinal barrier integrity, especially in the context of injurious agents, such as alcohol. Circadian disruption may therefore represent a previously unrecognized risk factor underlying the susceptibility to or development of alcoholic liver disease, as well as other conditions associated with intestinal hyperpermeability and an endotoxin-triggered inflammatory state.
Forsyth, Christopher B.; Shaikh, Maliha; Cavanaugh, Kate; Tang, Yueming; Vitaterna, Martha Hotz; Song, Shiwen
Background Clinical and animal data indicate that gut-derived endotoxin and other luminal bacterial products are necessary cofactors for development of alcoholic liver disease (ALD). Although gut leakiness is clearly an important cause of endotoxemia in ALD, it cannot fully explain endotoxemia in all ALD subjects and thus other factors may be involved. One possible factor is a change in gut microbiota composition (dysbiosis). Thus, the aim of our study was to interrogate the gut bacterial microbiota in alcohol-fed rats to see if chronic alcohol consumption affects gut bacteria composition. Method Male Sprague-Dawley rats were given either alcohol or dextrose intragastrically by gavage twice daily for up to 10 weeks. A subgroup of rats was also given either a probiotic (lactobacillus GG) or a prebiotic (oats) by gavage. Ileal and colonic mucosal-attached microbiota composition were interrogated by Length Heterogeneity PCR (LH-PCR) fingerprinting. Results Bacterial microbiota composition in alcohol-fed rats is not different from dextrose fed rats at weeks 4 and 6. Mucosa-associated microbiota composition in the colon is altered at 10 weeks of daily alcohol gavage. Both LGG and oats prevented alcohol-induced dysbiosis up to 10 weeks of alcohol treatment. Conclusion Daily alcohol consumption for 10 weeks alters colonic mucosa- associated bacterial microbiota composition in rats. Our data showed, for the first time, that daily alcohol consumption can affect colonic microbiome composition and suggest that dysbiosis may be an important mechanism of alcohol-induced endotoxemia. Further studies are needed to determine how dysbiotic microbiota contributes to development of ALD and whether therapeutic interventions targeted towards dysbiotic microbiota can prevent complications of alcoholism like ALD.
Mutlu, Ece; Keshavarzian, Ali; Engen, Phillip; Forsyth, Christopher B.; Sikaroodi, Masoumeh; Gillevet, Patrick
Infectious diarrhoea is a significant contributor to morbidity and mortality worldwide. In bacterium-induced diarrhoea, rapid loss of fluids and electrolytes results from inhibition of the normal absorptive function of the intestine as well as the activation of secretory processes. Advances in the past 10 years in the fields of gastrointestinal physiology, innate immunity and enteric bacterial virulence mechanisms highlight the
V. K. Viswanathan; Kim Hodges; Gail Hecht
OBJECTIVE:Small intestinal bacterial overgrowth syndrome (SIBOS) is characterized by an abnormally high bacterial population level in the upper gut, exceeding 105 organisms\\/ml (5 log colony-forming unit (CFU)\\/ml). To understand its origin and select an appropriate antibiotic treatment, we have analyzed the bacterial populations contaminating the upper gut in SIBOS patients.METHODS:Jejunal samples of 63 consecutive patients with diarrhea or malabsorption and
Yoram Bouhnik; Sophie Alain; Alain Attar; Bernard Flourié; Laurent Raskine; Marie José Sanson-Le Pors; Jean-Claude Rambaud
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 H2O2 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 H2O2-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.
Voigt, Robin M.; Shaikh, Maliha; Tang, Yueming; Cederbaum, Arthur I.; Turek, Fred W.; Keshavarzian, Ali
The mammalian gastrointestinal (GI) tract provides a complex and competitive environment for the microbiota1. Successful colonization by pathogens depends on scavenging nutrients, sensing chemical signals, competing with the resident bacteria, and precisely regulating expression of virulence genes2. The GI pathogen enterohemorrhagic E.coli (EHEC) relies on inter-kingdom chemical sensing systems to regulate virulence gene expression3–4. Here we show that these systems control the expression of a novel two-component signal transduction system, named FusKR, where FusK is the histidine sensor kinase (HK), and FusR the response regulator (RR). FusK senses fucose and controls expression of virulence and metabolic genes. This fucose-sensing system is required for robust EHEC colonization of the mammalian intestine. Fucose is highly abundant in the intestine5. Bacteroides thetaiotaomicron (B.theta) produces multiple fucosidases that cleave fucose from host glycans, resulting in high fucose availability in the gut lumen6. During growth in mucin, B.theta contributes to EHEC virulence by cleaving fucose from mucin, thereby activating the FusKR signaling cascade, modulating EHEC’s virulence gene expression. Our findings suggest that EHEC uses fucose, a host-derived signal made available by the microbiota, to modulate EHEC pathogenicity and metabolism.
Pacheco, Alline R.; Curtis, Meredith M.; Ritchie, Jennifer M.; Munera, Diana; Waldor, Matthew K.; Moreira, Cristiano G.; Sperandio, Vanessa
Background This study aimed to investigate the mechanism of the probiotic VSL#3 in acute alcoholic intestinal injury, and evaluate the effect of VSL#3, glutamine,VSL#3+glutamine and heat-killed VSL#3 therapy in a rat model. Methods Six- to eight-week-old male wild-type rats were divided into seven groups. To establish the acute alcohol liver disease model, rats received three doses of corn starch dissolved in PBS/40% alcohol administered intra-gastrically every 12 hours. Treatment groups received an intra-gastric dose of VSL#3, Glutamine, heat-killed VSL#3, or VSL#3+Glutamine 30 minutes prior to alcohol administration. The placebo group was treated with PBS prior to alcohol administration. TNF? and endotoxin in plasma was measured by ELISA and Tachypleus Ameboctye Lysate assays, and electron microscopy, Western blotting, and reverse transcription polymerase chain reaction were used to identify the mechanisms of VSL#3 in the regulation of epithelial permeability. Results First, compared with control group, endotoxin and TNF? in alcohol group was obviously high. At the same time, in VSL#3 group,the expression of endotoxin and TNF? obviously lower than the alcohol group. And the trends of the expression of tight junction proteins in these groups were reversed with the change of endotoxin and TNF?. Second, compared the groups of VSL#3 with glutamine,VSL#3+glutamine and heat-killed VSL#3,we found that both VSL#3 and heat-killed VSL#3, glutamine were as effective as VSL#3+glutamine in the treatment of acute alcohol liver disease, the expression of endotoxin and TNF? were lower than the alcohol group, and tight junction proteins were higher than the alcohol group whereas the expression of tight junction proteins were higher in VSL#3 + glutamine group than either agent alone, but have no significant difference. Conclusion We conclude that VSL#3 treatment can regulate the ecological balance of the gut microflora, preventing passage of endotoxin and other bacterial products from the gut lumen into the portal circulation and down-regulating the expression of TNF?, which could otherwise down-regulate the expression of tight junction proteins and increase epithelial permeability.
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
The small intestinal bacterial flora of 15 patients with chronic renal insufficiency was compared with that of subjects with blind loop syndrome. 9 patients were on regular hemodialysis with high protein intake and 6 (serum creatinine 7.5 to 12.5 mg\\/dl) were maintained on low protein diet. The chronic renal patients harbored a greatly increased microbial flora of both anaerobes and
Michael L. Simenhoff; Jussi J. Saukkonen; James F. Burke; Russell W. Schaedler; Susan J. Gordon
Altered gastrointestinal (GI) motility is seen in many pathological conditions. Reduced motility is one of the risk factors for development of a small intestinal bacterial overgrowth (SIBO). Hypothyroidism is associated with altered GI motility. The aim of this article was to study the link between hypothyroidism, altered GI motility and development of SIBO. Published literature was reviewed to study the association of altered GI motility, SIBO and hypothyroidism. Altered GI motility leads to SIBO. SIBO is common in patients with hypothyroidism. Patients with chronic GI symptoms in hypothyroidism should be evaluated for the possibility of SIBO. Both antibiotics and probiotics have been studied and found to be effective in management of SIBO.
Patil, Anant D.
Acute toxic interactions of intravenously administered benzyl alcohol and Escherichia coli O55:B5 (Boivin preparation) endotoxin were examined in rodents. Lethality studies in male CD-1 mice demonstrated that these agents were more toxic when administered in combination than when either was administered alone. Prophylactic treatment with diazepam (5 mg/kg intraperitoneally) protected against lethality induced by either the combination or the endotoxin yet offered little, if any, protection against the lethal effects of benzyl alcohol. Similar treatments with naloxone (5 mg/kg intraperitoneally) failed to protect against either endotoxin-induced or benzyl alcohol-induced lethality, but they significantly protected against the lethal effects of the combination. Although hexobarbital-induced sleeping time was prolonged in endotoxin-treated mice (but was normal in benzyl alcohol-treated mice), a more protracted effect on sleeping time was observed in mice treated with both benzyl alcohol and endotoxin. Moreover, male Wistar rats treated with benzyl alcohol (40 mg) showed no evidence of hepatic lesions, but rats treated in combination with sublethal doses of the alcohol (40 mg) and the endotoxin (0.4 mg) developed hepatic lesions which were severe than those observed in rats treated with endotoxin (0.4 mg) alone. A correlation between altered blood chemistry values and severity of hepatic lesions was demonstrated. These data show in vivo toxic interactions between benzyl alcohol and bacterial endotoxin. In addition, our results indicate that the toxic effects induced by the benzyl alcohol-endotoxin combination are due to an enhancement of the lethal properties of bacterial endotoxin. Images
Cebula, T A; El-Hage, A N; Ferrans, V J
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
The dose of warfarin needed to obtain a therapeutic anticoagulation level varies widely among patients and can undergo abrupt changes for unknown reasons. Drug interactions and genetic factors may partially explain these differences. Intestinal flora produces vitamin K2 (VK2) and patients with small intestinal bacterial overgrowth (SIBO) rarely present reduced INR values due to insufficient dietary vitamin K. The present study was undertaken to investigate whether SIBO occurrence may affect warfarin dose requirements in anticoagulated patients. Based on their mean weekly dose of warfarin while on stable anticoagulation, 3 groups of 10 patients each were defined: low dose (LD,
Giuliano, Vittorio; Bassotti, Gabrio; Mourvaki, Evangelia; Castellani, Danilo; Filippucci, Esmeralda; Sabatino, Giuseppe; Gizzi, Stefania; Palmerini, Francesco; Galli, Francesco; Morelli, Olivia; Baldoni, Monia; Morelli, Antonio; Iorio, Alfonso
We recently reported the inflammation of the cystic fibrosis (CF) mouse small intestine, and we hypothesized bacterial overgrowth as a possible cause. Quantitative PCR of bacterial 16S genomic DNA in the CF mouse small intestine revealed an increase of greater than 40-fold compared to controls. Sequencing of 16S PCR products and Gram staining showed that the majority of bacteria in
Oxana Norkina; Tim G. Burnett; Robert C. De Lisle
This study investigates the bacterial diversity in the intestine of rock lobster Panulirus homarus during live transportation process lasting for 14h. The total viable count (TVC) in the intestine of P. homarus (Linnaeus, 1758) prior to packing (control) was 130.33 x 106 cfu ml-1. In the intestine of packed lobsters (experimental), the TVC showed an increasing trend and the recorded
GRASIAN IMMANUEL; PALANISAMY IYAPPA RAJ; PALANICHAMY ESAKKI RAJ; ARUNACHALAM PALAVESAM
When intestinal barrier function is damaged bacterial translocation (BT) can occur. The injury to intestinal barrier function caused by chemotherapy has been investigated in some studies, however, definitive evidence of BT caused by chemotherapy is lacking. The aim of this study was to investigate small intestinal barrier dysfunction and BT and to evaluate the preventive effect of granulocyte colony-stimulating factor
Desheng Song; Bin Shi; Hua Xue; Yousheng Li; Xiaodong Yang; Baojun Yu; Zhe Xu; Fukun Liu; Jieshou Li
Enteric bacterial translocation into extraintestinal sites has been proposed as a potential route for bacterial infection in acute liver failure. Bacterial overgrowth in the intestine plays an important role in the etiology of bacterial translocation from the gut. The aim of the present study was to evaluate the influence of exogenous cholecystokinin (CCK) on intestinal transit time, enteric bacterial overgrowth
Xiangdong Wang; Vasile Soltesz; Jan Axelson; Roland Andersson
Altered gastrointestinal (GI) motility is seen in many pathological conditions. Reduced motility is one of the risk factors for development of a small intestinal bacterial overgrowth (SIBO). Hypothyroidism is associated with altered GI motility. The aim of this article was to study the link between hypothyroidism, altered GI motility and development of SIBO. Published literature was reviewed to study the association of altered GI motility, SIBO and hypothyroidism. Altered GI motility leads to SIBO. SIBO is common in patients with hypothyroidism. Patients with chronic GI symptoms in hypothyroidism should be evaluated for the possibility of SIBO. Both antibiotics and probiotics have been studied and found to be effective in management of SIBO. PMID:24944923
Patil, Anant D
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
Background A powerful approach to understanding complex processes such as aging is to use model organisms amenable to genetic manipulation, and to seek relevant phenotypes to measure. Caenorhabditis elegans is particularly suited to studies of aging, since numerous single-gene mutations have been identified that affect its lifespan; it possesses an innate immune system employing evolutionarily conserved signaling pathways affecting longevity. As worms age, bacteria accumulate in the intestinal tract. However, quantitative relationships between worm genotype, lifespan, and intestinal lumen bacterial load have not been examined. We hypothesized that gut immunity is less efficient in older animals, leading to enhanced bacterial accumulation, reducing longevity. To address this question, we evaluated the ability of worms to control bacterial accumulation as a functional marker of intestinal immunity. Results We show that as adult worms age, several C. elegans genotypes show diminished capacity to control intestinal bacterial accumulation. We provide evidence that intestinal bacterial load, regulated by gut immunity, is an important causative factor of lifespan determination; the effects are specified by bacterial strain, worm genotype, and biologic age, all acting in concert. Conclusions In total, these studies focus attention on the worm intestine as a locus that influences longevity in the presence of an accumulating bacterial population. Further studies defining the interplay between bacterial species and host immunity in C. elegans may provide insights into the general mechanisms of aging and age-related diseases.
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
ObjectivesAltered 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.
Steingerdur Anna Gunnarsdottir; Riadh Sadik; Steven Shev; Magnus Simrén; Henrik Sjövall; Per-Ove Stotzer; Hasse Abrahamsson; Rolf Olsson; Einar S Björnsson
The potentially important roles of intestinal bacteria on immune response, disease resistance, and nutrition for the black tiger shrimp Penaeus monodon have been increasingly investigated. However, so far, little is known about the intestinal bacterial community of the shrimp in the commercial aquaculture settings. In this study, the intestinal bacterial communities of juvenile P. monodon (70 individuals) from eight commercial farms in Thailand were examined using 16S rDNA PCR-DGGE, and seven 16S rDNA clone libraries from representative DGGE profiles were constructed. Bacteria in the ?-Proteobacteria class were the only common bacteria group found in the intestinal tracts of shrimp from all farms. The dominant bacterial genera in the intestinal population of each shrimp varied among different farms, and these genera were Vibrio, Photobacterium, Aeromonas, or Propionigenium (phylum Fusobacteria). Other commonly found genera included Actinomyces, Anaerobaculum, Halospirulina, Pseudomonas, Mycoplasma, and Shewanella. Twelve phyla of bacteria including Proteobacteria, Firmicutes, Fusobacteria, Actinobacteria, Cyanobacteria, Tenericutes, Deinococcus-Thermus, Planctomycetes, Spirochaetes, Synergistetes, Thermotogae, and Verrucomicrobia were represented in the sequences. Additionally, strictly anaerobic bacteria such as Propionigenium and Fusibacter were found. These intestinal bacterial communities varied significantly among different commercial farms and were distinct from their rearing water. The results provide descriptive structures of the intestinal bacterial communities of P. monodon in commercial farms, which can further be applied to areas of research on the immunity, disease resistance, and nutrition of shrimp to improve aquaculture of the black tiger shrimp. PMID:21915632
Chaiyapechara, Sage; Rungrassamee, Wanilada; Suriyachay, Ittipon; Kuncharin, Yanin; Klanchui, Amornpan; Karoonuthaisiri, Nitsara; Jiravanichpaisal, Pikul
Azo dyes are widely used in dye manufacturing, paper printing, textile industries, and as tattoo pigmentation. Since intestinal and skin bacteria can metabolize certain azo dyes to carcinogenic compounds, many researchers have studied the azoreductases of these bacteria. In this study, we used a microarray method to identify the intestinal bacterial species from cultured fecal samples in Brain Heart Infusion
Rong-Fu Wang; Huizhong Chen; Donald D. Paine; Carl E. Cerniglia
The present study aimed to investigate the effects of alcohol on intestinal epithelial barrier permeability and expression of the tight junction-associated proteins, zonula occludens-1 (ZO-1) and claudin-1. An alcohol-treated Caco-2 intestinal epithelial cell monolayer in vitro model was used to investigate whether alcohol is able to induce intestinal barrier dysfunction and decrease expression of ZO-1 and claudin-1. MTT assay results revealed unaltered cell viability at alcohol concentrations of <5%. Caco-2 cells in the 5% alcohol-treated groups exhibited a significant time-dependent decrease in transepithelial electrical resistance (TEER) and an increase in fluorescent yellow flux rate compared with the control cells. ZO?l expression exhibited a progressive decline following 20 min of incubation, reached its minimum levels at 60 min and then showed an increasing trend following 60 min of incubation. In addition, claudin-1 expression exhibited a progressive increase following 60 min of incubation, reached its maximum levels at 60 min and then showed an increasing trend following 60 min of incubation. Alterations in the expression of the ZO-l and claudin-1 proteins revealed trends consistent with changes in the TEER value and the fluorescent yellow transmittance rate in the Caco-2 cells. The results of this study indicate that alcohol is able to increase the intestinal epithelial barrier permeability in a dose- and time-dependent manner. Alcohol induces a change in the expression of the tight junction-associated proteins, ZO-1 and claudin-1, which are two major sites of alcohol action, thus increasing intestinal epithelial barrier permeability. PMID:24718485
Wang, Ying; Tong, Jing; Chang, Bing; Wang, Baifang; Zhang, Dai; Wang, Bingyuan
The intestinal microbiota plays a pivotal role in maintaining human health and well-being. Previously, we have shown that mice deficient in the brush-border enzyme intestinal alkaline phosphatase (IAP) suffer from dysbiosis and that oral IAP supplementation normalizes the gut flora. Here we aimed to decipher the molecular mechanism by which IAP promotes bacterial growth. We used an isolated mouse intestinal loop model to directly examine the effect of exogenous IAP on the growth of specific intestinal bacterial species. We studied the effects of various IAP targets on the growth of stool aerobic and anaerobic bacteria as well as on a few specific gut organisms. We determined the effects of ATP and other nucleotides on bacterial growth. Furthermore, we examined the effects of IAP on reversing the inhibitory effects of nucleotides on bacterial growth. We have confirmed that local IAP bioactivity creates a luminal environment that promotes the growth of a wide range of commensal organisms. IAP promotes the growth of stool aerobic and anaerobic bacteria and appears to exert its growth promoting effects by inactivating (dephosphorylating) luminal ATP and other luminal nucleotide triphosphates. We observed that compared with wild-type mice, IAP-knockout mice have more ATP in their luminal contents, and exogenous IAP can reverse the ATP-mediated inhibition of bacterial growth in the isolated intestinal loop. In conclusion, IAP appears to promote the growth of intestinal commensal bacteria by inhibiting the concentration of luminal nucleotide triphosphates. PMID:24722905
Malo, Madhu S; Moaven, Omeed; Muhammad, Nur; Biswas, Brishti; Alam, Sayeda N; Economopoulos, Konstantinos P; Gul, Sarah Shireen; Hamarneh, Sulaiman R; Malo, Nondita S; Teshager, Abeba; Mohamed, Mussa M Rafat; Tao, Qingsong; Narisawa, Sonoko; Millán, José Luis; Hohmann, Elizabeth L; Warren, H Shaw; Robson, Simon C; Hodin, Richard A
Background and aim Chronic psychological stress, including water avoidance stress (WAS), induces intestinal mucosal barrier dysfunction and impairs mucosal defences against luminal bacteria. The aim of this study was to determine the ability of a defined probiotic regimen to prevent WAS induced intestinal pathophysiology. Methods Male rats were subjected to either WAS or sham stress for one hour per day for 10 consecutive days. Additional animals received seven days of Lactobacillus helveticus and L rhamnosus in the drinking water prior to stress and remained on these probiotics for the duration of the study. Rats were then sacrificed, intestinal segments assessed in Ussing chambers, and mesenteric lymph nodes cultured to determine bacterial translocation. Results All animals remained healthy for the duration of the study. Chronic WAS induced excess ion secretion (elevated baseline short circuit current) and barrier dysfunction (increased conductance) in both the ileum and colon, associated with increased bacterial adhesion and penetration into surface epithelial cells. Approximately 70% of rats subjected to WAS had bacterial translocation to mesenteric lymph nodes while there was no bacterial translocation in controls. Probiotic pretreatment alone had no effect on intestinal barrier function. However, WAS induced increased ileal short circuit current was reduced with probiotics whereas there was no impact on altered conductance. Pretreatment of animals with probiotics also completely abrogated WAS induced bacterial adhesion and prevented translocation of bacteria to mesenteric lymph nodes. Conclusion These findings indicate that probiotics can prevent chronic stress induced intestinal abnormalities and, thereby, exert beneficial effects in the intestinal tract.
Zareie, M; Johnson-Henry, K; Jury, J; Yang, P-C; Ngan, B-Y; McKay, D M; Soderholm, J D; Perdue, M H; Sherman, P M
We recently reported the inflammation of the cystic fibrosis (CF) mouse small intestine, and we hypothesized bacterial overgrowth as a possible cause. Quantitative PCR of bacterial 16S genomic DNA in the CF mouse small intestine revealed an increase of greater than 40-fold compared to controls. Sequencing of 16S PCR products and Gram staining showed that the majority of bacteria in the CF mouse intestine were gram negative. Bacteria were observed to colonize the mucus that accumulates in the intestinal lumen of mice with CF. Impaired Paneth cell defenses were suggested by observation of partially dispersed Paneth granules in the mucus plugs of CF mouse intestinal crypts, and this mucus was strongly immunoreactive for Paneth cell bactericidal products. The role of bacterial overgrowth in intestinal inflammation in CF was tested by treating mice with oral antibiotics (ciprofloxacin and metronidazole) for 3 weeks, which reduced bacterial load in the CF mouse small intestine over 400-fold. Antibiotic treatment decreased the expression of the inflammation-related genes mast cell protease 2, leucine-rich ?2 glycoprotein/leucine-rich high endothelial venule glycoprotein, suppressor of cytokine signaling 3, hematopoietic cell transcript 1, and resistin-like molecule ?/found in inflammatory zone 2, all of which were no longer expressed at levels significantly different from control levels. The reduction of intestinal bacteria also significantly improved the growth of CF mice but had no effect on the growth of wild-type mice. These data suggest that bacterial overgrowth in the CF mouse small intestine has a role in inflammation and contributes to the failure to thrive in this mouse model of CF.
Norkina, Oxana; Burnett, Tim G.; De Lisle, Robert C.
Seventeen paediatric patients with immunodeficiency syndromes (10 with selective IgA deficiency, four with panhypogammaglobulinaemia, and three with selective T cell deficiency) were investigated for bacterial overgrowth of the small intestine and gut permeability to macromolecules. Five of 12 patients showed viable bacterial counts of more than 2 x 10(5)\\/ml in jejunal fluid. Bacterial overgrowth was also confirmed indirectly by breath
C Pignata; G Budillon; G Monaco; E Nani; R Cuomo; G Parrilli; F Ciccimarra
The accumulation of certain species of bacteria in the intestine is involved in both tissue homeostasis and immune-mediated pathologies. The host mechanisms involved in controlling intestinal colonization with commensal bacteria are poorly understood. We observed that under specific pathogen–free or germ-free conditions, intragastric administration of Pseudomonas aeruginosa, E. coli, Staphylococcus aureus, or Lactobacillus gasseri resulted in increased colonization of the small intestine and bacterial translocation in mice lacking Cd1d, an MHC class I–like molecule, compared with WT mice. In contrast, activation of Cd1d-restricted T cells (NKT cells) with ?-galactosylceramide caused diminished intestinal colonization with the same bacterial strains. We also found prominent differences in the composition of intestinal microbiota, including increased adherent bacteria, in Cd1d–/– mice in comparison to WT mice under specific pathogen–free conditions. Germ-free Cd1d–/– mice exhibited a defect in Paneth cell granule ultrastructure and ability to degranulate after bacterial colonization. In vitro, NKT cells were shown to induce the release of lysozyme from intestinal crypts. Together, these data support a role for Cd1d in regulating intestinal colonization through mechanisms that include the control of Paneth cell function.
Nieuwenhuis, Edward E.S.; Matsumoto, Tetsuya; Lindenbergh, Dicky; Willemsen, Rob; Kaser, Arthur; Simons-Oosterhuis, Ytje; Brugman, Sylvia; Yamaguchi, Keizo; Ishikawa, Hiroki; Aiba, Yuji; Koga, Yasuhiro; Samsom, Janneke N.; Oshima, Kenshiro; Kikuchi, Mami; Escher, Johanna C.; Hattori, Masahira; Onderdonk, Andrew B.; Blumberg, Richard S.
Hepatic intestinal and whole body plasma clearance and appearance of noradrenaline (NA) was quantified in patients with alcoholic cirrhosis (n = 12) and in controls (n = 6). As NA may be released as well as removed in the same vascular bed, infusion of tritium labelled NA (3H-NA) was carried out during hepatic vein catheterisation in order to determine both flux rates. In alcoholic cirrhosis plasma concentrations of endogenous NA and adrenaline (A) were significantly above control values (NA: median 2.4 v 1.7 nmol/l, p less than 0.02; A: 0.38 v 0.19 nmol/l, p less than 0.01). Whole body clearance of 3H-NA equal in the two groups (1.6 v 1.7 l/min, ns), while as the overall appearance rate of NA was significantly higher in alcoholic cirrhosis (4.2 v 2.6 nmol/min, p less than 0.02) indicating an enhanced sympathoadrenal activity in this group. The hepatic intestinal clearances of A, NA, and 3H-NA were not significantly different in patients and controls, but the estimated hepatic intestinal spillover rate of NA was 0.24 nmol/min in patients as compared with 0.0 nmol/min in controls (p less than 0.02). As a result of portosystemic shunting in cirrhosis the present estimation of NA spillover represents a minimum value. Our results indicate that the augmented circulating catecholamines in cirrhosis do not result from diminished removal but are contributed to from increased sympathetic nervous activity in the hepatic intestinal area (enhanced mesenteric sympathetic nervous activity).
Henriksen, J H; Ring-Larsen, H; Christensen, N J
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
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
Uptake rates across the jejunal brush border have been measured for water-soluble fatty acids and alcohols and analyzed to determine the relative roles of the unstirred water layer and the lipid cell membrane as determinants of the in- testinal absorptive process. Initial studies involving measure- ment of time courses of electrical transients developed across the intestine exposed to poorly permeant
Verney L. Weel; John M. Dietachy
Background & Aims: To date, no studies concerning the presence of small intestinal bacterial overgrowth in patients with progressive familial intrahepatic cholestasis were published. Based upon characteristic of progressive familial intrahepatic cholestasis one can expect the coexistence of small intestinal bacterial overgrowth. The aim of the study was to assess the incidence of small intestinal bacterial overgrowth in patients with progressive familial intrahepatic cholestasis. Methods: 26 patients aged 8 to 25 years with progressive familial intrahepatic cholestasis were included in the study. Molecular analysis of ABCB11 gene was performed in the vast majority of patients. In all patients Z-score for body weight and height, biochemical tests (bilirubin, bile acid concentration, fecal fat excretion) were assessed. In all patients hydrogen-methane breath test was performed. Results: On the basis of first hydrogen-methane breath test, diagnosis of small intestinal bacterial overgrowth was confirmed in 9 patients (35%), 5 patients (19%) had borderline results. The second breath test was performed in 10 patients: in 3 patients results were still positive and 2 patients had a borderline result. The third breath test was conducted in 2 patients and positive results were still observed. Statistical analysis did not reveal any significant correlations between clinical, biochemical and therapeutic parameters in patients with progressive familial intrahepatic cholestasis and coexistence of small intestinal bacterial overgrowth. Conclusions: Our results suggest that small intestinal bacterial overgrowth is frequent in patients with progressive familial intrahepatic cholestasis. Moreover, it seems that this condition has the tendency to persist or recur, despite the treatment. PMID:24644547
Lisowska, Aleksandra; Kobelska-Dubiel, Natalia; Jankowska, Irena; Paw?owska, Joanna; Moczko, Jerzy; Walkowiak, Jaros?aw
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
Background: Acute pancreatitis (AP) initiates a generalized inflammatory response that increases intestinal permeability and promotes bacterial translocation (BT). Impairment of the intestinal epithelial barrier is known to promote BT. Glucagon-like peptide 2 (GLP-2), a 33 residue peptide hormone, is a key regulator of the intestinal mucosa by stimulating epithelial growth. The purpose of this study was to determine whether GLP-2
George J Kouris; Qiang Liu; H Rossi; Goldie Djuricin; Paulo Gattuso; C Nathan; Robert A Weinstein; Richard A Prinz
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
Background.Arginine is a dibasic amino acid with significant metabolic and immunologic, effects especially in trauma and stress situations. Arginine supplementation has been shown to promote wound healing and improve immune system. We designed a study to evaluate the effects of supplemental dietary arginine on intestinal mucosal recovery and bacterial translocation and bacterial clearance after induction of radiation injury in rats.Methods.Twenty-one
A. Tayfun Gurbuz; Joseph Kunzelman; Eric E. Ratzer
Summary The purpose of this study was to investigate bacterial translocation and change in intestinal permeability in patients after\\u000a abdominal surgery. Sixty-three patients undergoing elective abdominal surgery were enrolled in the study. Blood samples were\\u000a collected prior to operation and 2, 24, 48 h after surgery for bacterial culture, microbial DNA extraction, plasma D-lactate\\u000a and endotoxin measurement. PCR analysis was performed
Zhi Qiao; Zhanliang Li; Jiye Li; Lianrong Lu; Yi Lv; Junyou Li
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
Because of limitations imposed on the antibiotic use in animal industry, there is a need for alternatives to maintain the efficiency of production. One of them may be the use of fermented liquid feed (FLF) but how it affects gut ecology is poorly understood. We investigated the effect of three diets, standard dry feed (control), dry feed supplemented with antibiotics, and fermented liquid feed (FLF, fermented with Lactobacillus plantarum), on gut bacterial diversity in piglets. The structure of the ileal and caecal communities was estimated by sequencing the SSU rRNA gene libraries. Antibiotic-supplemented feed slightly increased bacterial diversity in the ileum but reduced it in the caecum while in FLF-fed animals bacterial diversity was elevated. The majority of bacterial sequences in the ileum of all three groups belonged to lactobacilli (92-98%). In the caecum the lactobacilli were still dominant in control and antibiotic-fed animals (59% and 64% of total bacterial sequences, respectively) but in FLF-fed animals they fell to 31% with the concomitant increase in the Firmicutes diversity represented by the Dorea, Coprococcus, Roseburia and Faecalibacterium genera. Thus FLF affects the gut ecology in a different way than antibiotics and contributes to the enhanced bacterial diversity in the gastrointestinal tract. PMID:19393756
Tajima, Kiyoshi; Ohmori, Hideyuki; Aminov, Rustam I; Kobashi, Yuri; Kawashima, Tomoyuki
Introduction: In our previous bacterial overgrowth (BO) of the small intestine was sig- nificantly more common study in patients with mild to moderate pancreatic insuffi- ciency than in cases with severe chronic pancreatitis. Probably the pancreas enzyme substitution, used only in the cases of severe pancreas insufficiency, had an important role in the treatment of BO. Aims: The purpose of
Á. Pap; E. Schäfer; M. Burai; R. Schwab
Alcohol and dietary fat both play an important role in alcohol-mediated multi-organ pathology, including gut and liver. In the present study we hypothesized that the combination of alcohol and dietary unsaturated fat (USF) would result in intestinal inflammatory stress and mucus layer alterations, thus contributing to disruption of intestinal barrier integrity. C57BL/6N mice were fed Lieber-DeCarli liquid diets containing EtOH and enriched in USF (corn oil/linoleic acid) or SF (medium chain triglycerides: beef tallow) for 8 weeks. Intestinal histology, morphometry, markers of inflammation, as well as levels of mucus protective factors were evaluated. Alcohol and dietary USF triggered an intestinal pro-inflammatory response, characterized by increase in Tnf-?, MCP1, and MPO activity. Further, alcohol and dietary USF, but not SF, resulted in alterations of the intestinal mucus layer, characterized by decreased expression of Muc2 in the ileum. A strong correlation was observed between down-regulation of the antimicrobial factor Cramp and increased Tnf-? mRNA. Therefore, dietary unsaturated fat (corn oil/LA enriched) is a significant contributing factor to EtOH-mediated intestinal inflammatory response and mucus layer alterations in rodents. PMID:23453163
Kirpich, Irina A; Feng, Wenke; Wang, Yuhua; Liu, Yanlong; Beier, Juliane I; Arteel, Gavin E; Falkner, K Cameron; Barve, Shirish S; McClain, Craig J
Alcohol and dietary fat both play an important role in alcohol-mediated multi-organ pathology, including gut and liver. In the present study we hypothesized that the combination of alcohol and dietary unsaturated fat (USF) would result in intestinal inflammatory stress and mucus layer alterations, thus contributing to disruption of intestinal barrier integrity. C57BL/6N mice were fed Lieber-DeCarli liquid diets containing EtOH and enriched in USF (corn oil/linoleic acid) or SF (medium chain triglycerides: beef tallow) for 8 weeks. Intestinal histology, morphometry, markers of inflammation, as well as levels of mucus protective factors were evaluated. Alcohol and dietary USF triggered an intestinal pro-inflammatory response, characterized by increase in Tnf-?, MCP1, and MPO activity. Further, alcohol and dietary USF, but not SF, resulted in alterations of the intestinal mucus layer, characterized by decreased expression of Muc2 in the ileum. A strong correlation was observed between down-regulation of the antimicrobial factor Cramp and increased Tnf-? mRNA. Therefore, dietary unsaturated fat (corn oil/LA enriched) is a significant contributing factor to EtOH-mediated intestinal inflammatory response and mucus layer alterations in rodents.
Kirpich, Irina A.; Feng, Wenke; Wang, Yuhua; Liu, Yanlong; Beier, Juliana I.; Arteel, Gavin E.; Falkner, K. Cameron; Barve, Shirish S.; McClain, Craig J.
We recently demonstrated that simian immunodeficiency virus (SIV) viral loads were significantly higher in the plasma of rhesus macaques consuming alcohol compared with controls following intrarectal SIV infection. To understand the possible reasons behind increased viral replication, here we assessed the effects of chronic alcohol consumption on distribution and cycling of various lymphocyte subsets in the intestine. Macaques were administered alcohol (n = 11) or sucrose (n = 12), and percentages of memory and naive and activated lymphocyte subsets were compared in the blood, lymph nodes, and intestines. Although minimal differences were detected in blood or lymph nodes, there were significantly higher percentages of central memory (CD95+CD28+) CD4+ lymphocytes in the intestines from alcohol-receiving animals before infection compared with controls. In addition, higher percentages of naive (CD45RA+CD95-) as well as CXCR4+CD4 cells were detected in intestines of alcohol-treated macaques. Moreover, alcohol consumption resulted in significantly lower percentages of effector memory (CD95+CD28-) CD8 lymphocytes as well as activated Ki67+CD8 cells in the intestines. A subset (7 receiving alcohol and 8 receiving sucrose) were then intrarectally inoculated with SIV(mac251). Viral RNA was compared in different tissues using real-time PCR and in situ hybridization. Higher levels of SIV replication were observed in tissues from alcohol-consuming macaques compared with controls. Central memory CD4 lymphocytes were significantly depleted in intestines and mesenteric lymph nodes from all alcohol animals at 8 weeks postinfection. Thus, changes in the mucosal immune compartment (intestines) in response to alcohol are likely the major reasons behind higher replication of SIV observed in these animals. PMID:16652027
Poonia, Bhawna; Nelson, Steve; Bagby, Greg J; Veazey, Ronald S
The aim of this prospective study was to assess pulmonary and intestinal permeability (PP and IP, respectively) in patients with alcoholic liver cirrhosis (ALC). Thirty-five non-smoking patients with biopsy-proven ALC were included (mean grade B in Child's classification). None had a previous history of pulmonary disease and all had a normal chest radiograph and computed tomography scan. Lung function tests
Damien Huglo; Stéphane De Botton; Valérie Canva-Delcambre; Jean-Fréderic Colombel; Benoit Wallaert; Marc Steinling; Xavier Marchandise
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
Yuhua Z. Farnell; Gregg C. Allen; Nichole Neuendorff; James R. West; A. Chen Wei-Jung; David J. Earnest
To develop a novel coating material for coronary covered stents, we prepared a kind of composite membrane which contains polyvinyl alcohol (PVA) and porcine small intestinal submucosa (SIS) powders crosslinked and heparinized by N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The amount of immobilized heparin increased with increasing ratios of EDC:heparin, and the maximum amount was approximately 60 µg heparin per
Tao Jiang; Guixue Wang; Juhui Qiu; Lailong Luo; Guoquan Zhang
The composition of bacterial community in the intestine of the white shrimp, Litopenaeus vannamei under laboratory culture condition was determined using the 16S rDNA clone library. 16s rRNA gene was amplified and a library was constructed by using the genomic DNA extracted from the bacteria in the shrimp intestine as template. 12 different RFLP patterns of the clones were obtained by restriction fragment length polymorphism analysis using Afa I and Msp I. Compared with the published sequences in GenBank database, sequencing results of cloned 16S rDNA amplicons revealed a diverse community including gamma-proteobacteria and Firmicutes in the intestine of artificial diet-fed shrimp. Results showed that the Firmicutes group can be a dominant component (75.4%) in the shrimp intestinal microflora and other clones belong to gamma-proteobacteria (24.6%) which were identified as Shewanella sp., Pantoea sp., Aranicola sp., Pseudomonas sp. and Vibrio sp., respectively. These results provide the first comprehensive description of microbial diversity of the white shrimp intestine and suggest that most of the bacteria associated with shrimp intestine are uncultured and novel species. PMID:17944366
Li, Ke; Zheng, Tian-ling; Tian, Yun; Yuan, Jian-jun
Small bowel bacterial overgrowth (SBBO), in which colon-derived bacteria colonize the upper small bowel, is found in a wide\\u000a variety of adult diseases associated with intestinal failure and dysfunction, including short bowel syndrome and other conditions\\u000a following massive bowel resection, dysmotility disorders, and inflammatory bowel disease. SBBO also appears to be relatively\\u000a common in the elderly, in whom it often
Thomas R. Ziegler; Conrad R. Cole
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
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
Infections with intestinal helminth and bacterial pathogens, such as enteropathogenic Escherichia coli, continue to be a major global health threat for children. To determine whether and how an intestinal helminth parasite, Heligomosomoides polygyrus, might impact the TLR signaling pathway during the response to a bacterial enteropathogen, MyD88 knockout and wild-type C57BL/6 mice were infected with H. polygyrus, the bacterial enteropathogen Citrobacter rodentium, or both. We found that MyD88 knockout mice co-infected with H. polygyrus and C. rodentium developed more severe intestinal inflammation and elevated mortality compared to the wild-type mice. The enhanced susceptibility to C. rodentium, intestinal injury and mortality of the co-infected MyD88 knockout mice were found to be associated with markedly reduced intestinal phagocyte recruitment, decreased expression of the chemoattractant KC, and a significant increase in bacterial translocation. Moreover, the increase in bacterial infection and disease severity were found to be correlated with a significant downregulation of antimicrobial peptide expression in the intestinal tissue in co-infected MyD88 knockout mice. Our results suggest that the MyD88 signaling pathway plays a critical role for host defense and survival during helminth and enteric bacterial co-infection.
Su, Libo; Qi, Yujuan; Zhang, Mei; Weng, Meiqian; Zhang, Xichen; Su, Chienwen; Shi, Hai Ning
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.
Fuhrer, Andrea; Sprenger, Norbert; Kurakevich, Ekaterina; Borsig, Lubor; Chassard, Christophe
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
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
Ethanol may have profound effects on both the distribution of perfusion and substrate utilization by the liver and heart due to its vasodilating properties and the generation of high levels of circulating acetate and lactate. Since fatty acids are highly extracted by the heart and liver under normal circumstances, changes in the relationship of perfusion/fatty acid uptake may be a sensitive indicator of both altered perfusion and changes in metabolic substrate availability. To test this hypothesis, studies were performed in rats fed 3.1, 6.2, and 9.3 g/kg doses of ethanol. Fatty acid uptake was estimated with a 3-methyl substituted reagent with a chain length equivalent to 17 carbons. The methyl group in the three position prevented beta oxidation and prolonged the residence of fatty acids in the tissue. Eighteen hours after acute alcohol administration, fatty acid uptake was reduced in the heart and the small intestine; in the liver uptake was increased or unchanged. Acute ethanol administration also resulted in increased perfusion, as indicated by enhanced uptake of 201thallium by the heart, liver, and small intestine. The fatty acid extraction of the heart, liver, and small intestine, defined as the concentration of fatty acid divided by the concentration of 201thallium, was markedly decreased by alcohol ingestion. These alcohol effects were dose-dependent and temporally related. The data suggest that ethanol ingestion could potentially alter heart function during exercise or following a prolonged fast, when the heart relies primarily upon fatty acids extracted from the circulation to generated adenosine triphosphate (ATP). PMID:2264611
Carter, E A; Barli-Kovach, M; Elmaleh, D; Livni, E; Strauss, H W
Liver cirrhosis is associated with bacterial translocation (BT) and endotoxemia. Most translocating bacteria belong to the common intestinal microbiota, suggesting a breakdown of intestinal barrier function. We hypothesized that diminished mucosal antimicrobial host defense could predispose to BT. Two rodent models of portal hypertension with increased BT were used, CCl(4)-induced ascitic cirrhosis and 2-day portal vein-ligated (PVL) animals. BT was assessed by standard microbiological techniques on mesenteric lymph nodes. Total RNA was isolated systematically throughout the intestinal tract, and expression of Paneth cell ?-cryptdins and ?-defensins was determined by real-time quantitative polymerase chain reaction (qPCR). To determine functional consequences, mucosal antimicrobial activity was assessed with a fluorescence-activated cell sorting assay. BT was detectable in 40% of rats with cirrhosis. Compared with the group without BT, these animals exhibited diminished intestinal Paneth cell ?-cryptdin 5 and 7 expression. In contrast, PVL was associated with BT in all animals but did not affect antimicrobial peptides. The decrease in Paneth cell antimicrobials was most pronounced in the ileum and the coecum. Other antimicrobials showed no changes or even an induction in the case of BT at different sites. Antimicrobial activity toward different commensal strains was reduced, especially in the distal ileum and the cecum in experimental cirrhosis with BT (excluding PVL). Conclusion: Compromised Paneth cell antimicrobial host defense seems to predispose to BT in experimental cirrhosis. Understanding this liver-gut axis including the underlying mechanisms could help us to find new treatment avenues. PMID:22095436
Teltschik, Zora; Wiest, Reiner; Beisner, Julia; Nuding, Sabine; Hofmann, Claudia; Schoelmerich, Juergen; Bevins, Charles L; Stange, Eduard F; Wehkamp, Jan
The human gut microbiota is inextricably linked to health and disease. One important function of the commensal organisms living in the intestine is to provide colonization resistance against invading enteric pathogens. Because of the complex nature of the interaction between the microbiota and its host, multiple mechanisms likely contribute to resistance. In this review, we dissect the biological role of short-chain fatty acids (SCFA), which are fermentation end products of the intestinal microbiota, in host–pathogen interactions. SCFA exert an extensive influence on host physiology through nutritional, regulatory, and immunomodulatory functions and can also affect bacterial fitness as a form of acid stress. Moreover, SCFA act as a signal for virulence gene regulation in common enteric pathogens. Taken together, these studies highlight the importance of the chemical environment where the biology of the host, the microbiota, and the pathogen intersects, which provides a basis for designing effective infection prevention and control.
Sun, Yvonne; O'Riordan, Mary X. D.
Background Gastrointestinal complaints are common among long distance runners. We hypothesised that small intestinal bacterial overgrowth\\u000a (SIBO) is present in long distance runners frequently afflicted with gastrointestinal complaints.\\u000a \\u000a \\u000a \\u000a \\u000a Findings Seven long distance runners (5 female, mean age 29.1 years) with gastrointestinal complaints during and immediately after\\u000a exercise without known gastrointestinal diseases performed Glucose hydrogen breath tests for detection of SIBO one week
Kai Schommer; Dejan Reljic; Peter Bärtsch; Peter Sauer
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
Weaning of the pig is generally regarded as a stressful event which could lead to clinical implications because of the changes\\u000a in the intestinal ecosystem. The functional properties of microbiota inhabiting the pig’s small intestine (SI), including\\u000a lactobacilli which are assumed to exert health-promoting properties, are yet poorly described. Thus, we determined the ecophysiology\\u000a of bacterial groups and within genus
Robert Pieper; Pawel Janczyk; Annette Zeyner; Hauke Smidt; Volker Guiard; Wolfgang Bernhard Souffrant
The aim of the investigation was to quantify selected dominant bacterial groups in the chicken intestinal tract. Conventional\\u000a production was used as model and the effect of the supplement with Salinomycin was evaluated. Hybridization conditions were\\u000a optimized for published probes with respect to a panel of reference bacteria. In chicken intestinal samples bacteria were\\u000a quantified by fluorescence in situ hybridization
K. N. Olsen; M. Henriksen; M. Bisgaard; O. L. Nielsen; H. Christensen
The bacteria in the large intestines of 10 northern leopard frogs (Rana pipiens) were enumerated and partially characterized. Four nonhibernating frogs were collected in the summer, four hibernating frogs were collected in the winter, and two frogs just emerged from hibernation were collected in the spring. All frogs had about 10(10) bacteria per g (wet weight) of intestinal contents and about 10(9) bacteria per g (wet weight) of mucosal scraping, although the counts from the winter frogs were slightly less than those from the other two groups of frogs. Another group of 14 summer frogs, after treatment to induce hibernation, showed a drop in bacterial counts accompanied by a change in the composition of the flora. In most frogs, Bacteroides was the dominant organism. Other bacteria repeatedly isolated at high dilutions were strict anaerobes, including butyrigenic and acetogenic helically coiled bacteria; fusobacteria; and acetogenic, small, gram-positive bacilli. These data indicate that the intestinal flora of frogs is similar to that of mammals and birds and that this flora can be maintained at temperatures close to freezing.
Gossling, J; Loesche, W J; Nace, G W
A new aerobic bacterial strain, CIP I-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 0.032ǂ.004 h-1 and 35.8Ǌ.5 mg TBA·g-1 (cell
P. Piveteau; F. Fayolle; J.-P. Vandecasteele; F. Monot
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
HE influence of various fruits upon gastro-intestinal function has been studied in this laboratory for the past few years. The intra-alimentary contents, from the oral cavity to the anal opening, depend upon the materials ingested, the fluids secreted, and the bacterial flora in the lumen of this tract. We have been particularly interested in the bacterial flora and the acid-base
Olaf Bergeim; Arthur Hanszen; Lloyd Arnold
The attractant betaine and the antibiotic growth promoter florfenicol are commonly used together in Chinese fresh water aquaculture, but there is no information about the effect of these two feed additive on the intestinal autochthonous bacterial community in hybrid tilapia (Oreochromis nilotica ? × O. aureas ?). Hybrid tilapia (240 fish in total; 20 fish per net cage; three cages per group) were divided into four dietary groups: control group, no betaine or florfenical addition (CK); betaine group, 0.1% betaine added (B); florfenicol group, 0.002% florfenicol added (F); and combination group, 0.1% betaine and 0.002% florfenicol added together (BF). After 8 weeks of feeding, six fish from each cage were chosen randomly, the guts were sampled and pooled, and their intestinal autochthonous bacterial communities were analyzed by 16S rDNA-denaturing gradient gel electrophoresis. Enumeration of total gut autochthonous bacteria was analyzed by quantitative PCR with rpoB as the endogenous control. The results showed that the fish intestinal bacteria of group B were more diverse than that of CK, and that of F and BF groups was reduced in the total numbers and limited to certain bacterial species or genera (P < 0.05). This study revealed that betaine can promote some intestinal autochthonous bacteria, and florfenicol play a depressor role. When combined together, florfenicol may overshadow the effect of betaine on the predominant intestinal bacteria of tilapia. PMID:22805797
He, Suxu; Zhou, Zhigang; Liu, Yuchun; Cao, Yanan; Meng, Kun; Shi, Penjun; Yao, Bin; Ringø, Einar
The effect of extremely low electrical currents, identical to those generated by the gut smooth muscle, on bacterial autolysin production in vitro was tested in the present study. When stimulated with these electrical currents, the bacteria Pediococcus pentosaceus 16:1 produced groups of peptidoglycan hydrolases that differed from those produced by the unstimulated (control) bacteria. The autolysins synthesized by the P. pentosaceus 16:1 under extremely low electrical currents were effective against peptidoglycans from the cell walls of various lactic acid bacteria strains, whereas the autolysins from the control bacteria acted exclusively against P. pentosaceus 16:1 cell walls. Thus, it can be predicted that in vivo the electrical currents generated by the intestinal smooth muscles, which can be recorded as the myoelectrical migrating complexes, could regulate lactic acid bacteria strain growth in the gut. PMID:16118236
Kruszewska, Danuta; Podgurniak, Pawel; Ljungh, Asa; Sebastian, Aleksandra; Larsson, Lennart; Zajdel-Dabrowska, Jolanta; Pierzynowski, Stefan G
Background: Intestinal ischemia and reperfusion may be the primary triggers of mucosal barrier impairment, cytokine expression, and bacterial translocation (BT). Trapidil is a phosphodiesterase and platelet-derived growth factor inhibitor that reduces lipid peroxidation and inhibits the production of cytokines. Objective: The goal of this study was to assess whether trapidil might protect the intestinal epithelial barrier by inhibiting lipid peroxidation and proinflammatory cytokines by testing the effect of trapidil on intestinal barrier function in an experimental ischemia/reperfusion (I/R) rat model. Methods: Trapidil was used in a rat model of intestinal barrier dysfunction caused by intestinal ischemia for 40 minutes followed by reperfusion for 12 hours. To do this, the rats were randomized to 1 of 4 treatment groups, as follows: (1) sham surgery and saline administration (1 mL IV) (Sham group); (2) sham surgery and trapidil administration (8 mg/kg IV) (Sham+T group); (3) I/R and saline administration (1 mL IV) (I/R group); and (4) I/R and trapidil administration (8 mg/kg IV) (I/R+T group). Intestinal barrier function was assessed by histopathologic examination, blood malondialdehyde (MDA) level, and BT. Results: The I/R+T group showed significantly less incidence of BT compared with the I/R group in the liver and reduced median colony count of translocated bacteria in mesenteric lymph nodes, liver, spleen, and peritoneum compared with the I/R group. Furthermore, the mean blood MDA level demonstrated that lipid peroxidation was significantly decreased in the I/R+T group compared with the I/R group. Histopathologic findings revealed that trapidil administration before reperfusion preserved intestinal mucosal integrity and inhibited the infiltration of inflammatory cells into the intestines. Conclusions: In this experimental study, a correlation seemed to exist between intestinal barrier dysfunction and BT. Intestinal barrier dysfunction may allow a large amount of bacteria to pass from the gut to distant organs. Trapidil treatment may inhibit BT by preserving intestinal barrier by inhibiting thromboxane A2, lipid peroxidation, proinflammatory cytokines, and stimulated prostacyclin. Future dose- and time-dependent studies will be helpful in revealing the effects of trapidil on BT.
Colak, Tahsin; Ozturk, Candan; Polat, Ayse; Bagdatoglu, Ozlen; Kanik, Arzu; Turkmenoglu, Ozgur; Aydin, Suha
Alcoholic liver disease is a leading cause of morbidity and liver-related death worldwide. Intestinal bacterial overgrowth and dysbiosis induced by ethanol ingestion play an important role in the pathogenesis of alcoholic liver disease. After exposure to alcohol in the lumen, enteric bacteria alter their metabolism and thereby disturb intestinal homeostasis. Disruption of the mucosal barrier results in the translocation of microbial products that contribute to liver disease by inducing hepatic inflammation. In this review, we will discuss the effects of alcohol on the intestinal microbiome, and in particular, its effects on bacterial metabolism, bacterial translocation and ecological balance. A better understanding of the interactions among alcohol, the host and the microbiome will reveal new targets for therapy and lead to new treatments.
The human intestine harbors a diverse community of microbes that promote metabolism and digestion in their symbiotic relationship with the host. Disturbance of its homeostasis can result in disease. We review factors that disrupt intestinal homeostasis and contribute to nonalcoholic fatty liver disease, steatohepatitis, alcoholic liver disease, and cirrhosis. Liver disease has long been associated with qualitative and quantitative (overgrowth) dysbiotic changes in the intestinal microbiota. Extrinsic factors, such as the Western diet and alcohol, contribute to these changes. Dysbiosis results in intestinal inflammation, a breakdown of the intestinal barrier, and translocation of microbial products in animal models. However, the contribution of the intestinal microbiome to liver disease goes beyond simple translocation of bacterial products that promote hepatic injury and inflammation. Microbial metabolites produced in a dysbiotic intestinal environment and host factors are equally important in the pathogenesis of liver disease. We review how the combination of liver insult and disruptions in intestinal homeostasis contribute to liver disease. PMID:24440671
Schnabl, Bernd; Brenner, David A
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.
Robertson, Susan J.; Zhou, Jun Yu; Geddes, Kaoru; Rubino, Stephen J.; Cho, Joon Ho; Girardin, Stephen E.; Philpott, Dana J.
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.
Dysfunction of Paneth and goblet cells in the intestine contributes to inflammatory bowel disease (IBD) and colitis-associated colorectal cancer (CAC). Here, we report a role for the NAD+-dependent histone deacetylase SIRT1 in the control of anti-bacterial defense. Mice with an intestinal specific Sirt1 deficiency (Sirt1int?/?) have more Paneth and goblet cells with a consequent rearrangement of the gut microbiota. From a mechanistic point of view, the effects on mouse intestinal cell maturation are mediated by SIRT1-dependent changes in the acetylation status of SPDEF, a master regulator of Paneth and goblet cells. Our results suggest that targeting SIRT1 may be of interest in the management of IBD and CAC.
Lo Sasso, Giuseppe; Ryu, Dongryeol; Mouchiroud, Laurent; Fernando, Samodha C.; Anderson, Christopher L.; Katsyuba, Elena; Piersigilli, Alessandra; Hottiger, Michael O.; Schoonjans, Kristina; Auwerx, Johan
Irritable bowel syndrome (IBS) is a common condition characterized by abdominal pain or discomfort, bloating, and altered stool form and passage. Small intestinal bacterial overgrowth (SIBO) is a condition in which there is overgrowth of bacteria in small bowel in excess of 10? colony forming units per milliliter on culture of the upper gut aspirate. Frequency of SIBO varied from 4%-78% among patients with IBS and from 1%-40% among controls. Higher frequency in some studies might be due to fallacious criteria [post-lactulose breath-hydrogen rise 20 PPM above basal within 90 min (early-peak)]. Glucose hydrogen breath test (GHBT) has a low sensitivity to diagnose SIBO. Hence, studies based on GHBT might have under-estimated frequency of SIBO. Therefore, it is important to analyze these studies carefully to evaluate whether the reported association between IBS and SIBO is over or under-projected. This review evaluates studies on association between SIBO and IBS, discordance between different studies, their strength and weakness including methodological issues and evidence on therapeutic manipulation of gut flora on symptoms of IBS. PMID:24627585
Ghoshal, Uday C; Srivastava, Deepakshi
AIM: To estimate the prevalence of small intestinal bacterial overgrowth (SIBO) in our geographical area (Western Sicily, Italy) by means of an observational study, and to gather information on the use of locally active, non-absorbable antibiotics for treatment of SIBO. METHODS: Our survey included 115 patients fulfilling the Rome II criteria for diagnosis of irritable bowel syndrome (IBS); a total of 97 patients accepted to perform a breath test with lactulose (BTLact), and those who had a positive test, received Rifaximin (Normix®, Alfa Wassermann) 1200 mg/d for 7 d; 3 wk after the end of treatment, the BTLact was repeated. RESULTS: Based on the BTLact results, SIBO was present in about 56% of IBS patients, and it was responsible for some IBS-related symptoms, such as abdominal bloating and discomfort, and diarrhoea. 1-wk treatment with Rifaximin turned the BTLact to negative in about 50% of patients and significantly reduced the symptoms, especially in those patients with an alternated constipation/diarrhoea-variant IBS. CONCLUSION: SIBO should be always suspected in patients with IBS, and a differential diagnosis is done by means of a “breath test”. Rifaximin may represent a valid approach to the treatment of SIBO.
Peralta, Sergio; Cottone, Claudia; Doveri, Tiziana; Almasio, Piero Luigi; Craxi, Antonio
The pathogenic bacterium Aeromonas salmonicida is the causative agent of furunculosis, a lethal disease in salmonids. The mode of lateral transmission has not been conclusively defined, but A. salmonicida is able to translocate across the intestinal epithelium of salmonids, making the intestinal route a probable candidate. This study investigated some of the virulence mechanisms used by the bacteria to promote translocation. Intestinal segments were placed in modified Ussing chambers to investigate epithelial functions during exposure to bacterial factors. The factors were: extracellular products (ECP), lipopolysaccharide (LPS) or live or heat-inactivated A. salmonicida. Fluorescein isothiocynate (FITC)-labelling enabled detection of translocated bacteria by fluorometry. Live A. salmonicida translocated to a greater degree than heat-inactivated bacteria, suggesting that the bacteria utilize a heat sensitive surface-bound virulence factor which promotes translocation. The epithelium was negatively affected by ECP, manifested as decreased net ion transport, indicating a disturbance in ion channels or cell metabolism. LPS did not affect the epithelium in vitro when administered on the luminal side of the intestinal segment, but significantly increased epithelial translocation of fluorescent bacterial-sized microspheres when administered on the serosal side. This is suggested to be caused by increased transcellular transport, as the paracellular permeability was unaffected indicating maintained epithelial integrity. PMID:18234022
Jutfelt, F; Sundh, H; Glette, J; Mellander, L; Thrandur Björnsson, B; Sundell, K
OBJECTIVES:Altered small-bowel motility, lengthening of the orocecal transit time, and small-intestinal bacterial overgrowth have been described in patients with liver cirrhosis. These changes might be related to the progressive course and poor prognosis of the disease. We investigated the effect of a long-term treatment with cisapride and an antibiotic regimen on small-intestinal motor activity, orocecal transit time, bacterial overgrowth, and
Ana Maria Madrid; Carmen Hurtado; Mauricio Venegas; Francisco Cumsille; Carlos Defilippi
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
Background: A modification of the intestinal flora and an increased bacterial translocation is a common finding in patients with inflammatory bowel disease as well as in animal model of colitis. Rifaximin, a non-absorbable derivative of rifamycin, is an effective antibiotic that acts by inhibiting bacterial ribonucleic acid synthesis. Aims: In the present study, we investigated the effect of the administration
Stefano Fiorucci; Eleonora Distrutti; Andrea Mencarelli; Miriam Barbanti; Ernesto Palazzini; Antonio Morelli
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
Recent findings from our laboratory have shown that acute alcohol (EtOH) intoxication before burn injury impairs intestinal immunity and barrier functions. To further delineate the mecha- nism of impaired intestinal barrier function, the present study examined the role of corticosterone (CORT) and interleukin (IL)-18, as CORT and IL-18 are elevated following a combined insult of EtOH intoxication and burn injury.
Xiaoling Li; Shadab N. Rana; Martin G. Schwacha; Irshad H. Chaudry; Mashkoor A. Choudhry
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
Introduction Whether intestinal dysmotility and proton pump inhibitor (PPI) use either independently or together contributes to small intestinal bacterial overgrowth (SIBO), and/or small intestinal fungal overgrowth (SIFO) is not known. Aim Investigate the role of dysmotility and PPI use in patients with persistent gastrointestinal complaints. Methods Patients with unexplained gastrointestinal symptoms and negative endoscopy/radiology tests completed a validated symptom questionnaire and underwent 24-hour ambulatory antro-duodeno-jejunal manometry (ADJM). Simultaneously, duodenal aspirate was obtained for aerobic, anaerobic and fungal culture. Dysmotility was diagnosed by (> 2): absent phase III MMC, absent/diminished postprandial response, diminished amplitude of antral/intestinal phasic activity, impaired antro-duodenal coordination. Bacterial growth ?103 CFU/mL or fungal growth was considered evidence for SIBO/SIFO. PPI use was documented. Correlation of symptoms with presence of SIBO or SIFO were assessed. Results 150 subjects (M/F=47/103) were evaluated; 94/150 (63%) had overgrowth: 38/94 (40%) had SIBO, 24/94 (26%) had SIFO, and 32/94 (34%) had mixed SIBO/SIFO. SIBO was predominately due to Streptococcus, Enterococcus, Klebsiella, and E. coli. SIFO was due to Candida. 80/150 (53%) patients had dysmotility and 65/150 (43%) used PPI. PPI use (p=.0063) and Dysmotility (p=.0003) were independent significant risk factors (p<0.05) for overgrowth, but together did not pose additional risk. Symptom profiles were similar between those with or without SIBO/SIFO. Conclusions Dysmotility and PPI use were independent risk factors for SIBO or SIFO and were present in over 50% of subjects with unexplained gastrointestinal symptoms. Diagnosis of overgrowth requires testing because symptoms were poor predictors of overgrowth.
Jacobs, C; Coss Adame, E; Attaluri, A; Valestin, J; Rao, SSC
The influence of three antibiotics (bacitracin, enrofloxacin, and neomycin sulfate) on the mucosa-associated enteric microbiota and the intestines of mice was examined. Antibiotics caused conspicuous enlargement of ceca and an increase in overall length of the intestine. However, there were no pathologic changes associated with increased cecal size or length of the intestine. Conspicuous reductions in the richness of mucosa-associated bacteria and changes to community profiles within the small (duodenum, proximal jejunum, middle jejunum, distal jejunum, and ileum) and large (cecum, ascending colon, and descending colon) intestine occurred in mice administered antibiotics. Communities in antibiotic-treated mice were dominated by a limited number of Clostridium-like (i.e. clostridial cluster XIVa) and Bacteroides species. The richness of mucosa-associated communities within the small and large intestine increased during the 14-day recovery period. However, community profiles within the large intestine did not return to baseline (i.e. relative to the control). Although antibiotic administration greatly reduced bacterial richness, densities of mucosa-associated bacteria were not reduced correspondingly. These data showed that the antibiotics, bacitracin, enrofloxacin, and neomycin sulfate, administered for 21 days to mice did not sterilize the intestine, but did impart a tremendous and prolonged impact on mucosa-associated bacterial communities throughout the small and large intestine. PMID:22185696
Puhl, Nathan J; Uwiera, Richard R E; Yanke, L Jay; Selinger, L Brent; Inglis, G Douglas
The use of alcohol is woven into our culture in a most complex fashion. The majority of adults in the United States consume\\u000a alcohol, yet alcohol also causes nearly 75,000 deaths per year and costs our society on the order of 150 billion per year.\\u000a Harm from alcohol can occur in a number of ways. First, if alcohol is consumed
James C. Garbutt
The objective of this study was to determine whether host, compartment, or environmental specific factors play an important role in the establishment of the intestinal microflora in broiler chickens during growth. This objective was addressed using a 16S rDNA approach. PCR-amplicons from the V6 to V8 regions of the 16S rDNA of intestinal samples were separated by denaturing gradient gel
P. W. J. J. Wielen; D. A. Keuzenkamp; L. J. A. Lipman; F. Knapen; S. Biesterveld
SUMMARY 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.
Farache, Julia; Koren, Idan; Milo, Idan; Gurevich, Irina; Kim, Ki-Wook; Zigmond, Ehud; Furtado, Glaucia C.; Lira, Sergio A.; Shakhar, Guy
Seasonal quantitative and qualitative analyses of the bacterial flora associated with the intestine of hybrid tilapia (Oreochromis niloticus×Oreochromis aureus) cultured in earthen ponds in Saudi Arabia were carried out. The isolates were being identified to genus or species level. Total viable counts (TVC) of bacteria in the intestine varied between 6.8±1.9×106 to 7.5±1.4×107 colony forming units (cfu) g?1 in early
Ahmed H Al-Harbi; M Naim Uddin
Moderate consumption of red wine has been associated with beneficial effects on human health, and this has been attributed to the flavonoid content. Factors that influence the bioavailability of this group of polyphenolic compounds are therefore important. Using the rat cannulated everted jejunal sac technique, we have investigated the effect of alcohol on the intestinal absorption of quercetin and its 3-O-glucoside from red wine. Tissue preparations were incubated in whole or dealcoholised red wine, diluted 1?:?1 with Krebs buffer for 20?min at 37°C, after which the mucosa was removed and processed for HPLC analysis. Tissues exposed to red wine had significantly higher amounts of both quercetin (× 3; P<0.001) and quercetin-3-O-glucoside (× 1.5; P<0.01) associated with them, compared with sacs incubated in the dealcoholised equivalent. In addition, both tamarixetin (T) and isorhamnetin (I), in the mucosal tissue from sacs exposed to the whole wine, were significantly elevated approximately two fold (P<0.05; P<0.01, respectively). Similar results were obtained when sacs were incubated in Krebs buffer containing a mixture of pure quercetin and quercetin-3-O-glucoside with or without alcohol, and, although effects on the apparent absorption of Q and Q-3-G were not so marked, concentrations of the metabolites quercetin-3-O-glucuronide and I were significantly increased by the presence of alcohol (P<0.01 and P<0.001, respectively). It is therefore plausible that the moderate alcohol content of red wine contributes to its beneficial health effects in humans by both increasing the absorption of quercetin and quercetin-3-O-glucoside and by channelling their metabolism towards O-methylation to yield compounds (T and I), which have potential protective effects against cancer and cardiovascular diseases.
Dragoni, Stefania; Gee, Jennifer; Bennett, Richard; Valoti, Massimo; Sgaragli, Giampietro
Principles of protein thermostability have been studied by comparing structures of thermostable proteins with mesophilic counterparts that have a high degree of sequence identity. Two tetrameric NADP(H)-dependent alcohol dehydrogenases, one from Clostridium beijerinckii (CBADH) and the other from Thermoanaerobacter brockii (TBADH), having exceptionally high (75%) sequence identity, differ by 30 degrees in their melting temperatures. The crystal structures of CBADH and TBADH in their holo-enzyme form have been determined at a resolution of 2.05 and 2.5 A, respectively. Comparison of these two very similar structures (RMS difference in Calpha = 0.8 A) revealed several features that can account for the higher thermal stability of TBADH. These include additional ion pairs, "charged-neutral" hydrogen bonds, and prolines as well as improved stability of alpha-helices and tighter molecular packing. However, a deeper structural insight, based on the location of stabilizing elements, suggests that enhanced thermal stability of TBADH is due mainly to the strategic placement of structural determinants at positions that strengthen the interface between its subunits. This is also supported by mutational analysis of structural elements at critical locations. Thus, it is the reinforcement of the quaternary structure that is most likely to be a primary factor in preserving enzymatic activity of this oligomeric bacterial ADH at elevated temperatures.
Korkhin, Y.; Kalb (Gilboa), A. J.; Peretz, M.; Bogin, O.; Burstein, Y.; Frolow, F.
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
Mono and multilayer composite films of poly(vinyl alcohol)-chitosan-bacterial cellulose (PVA/chitosan/BC) have been prepared to achieve controlled release of ibuprofen sodium salt (IbuNa) as model drug. The composite films have been characterized by Fourier transformed infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Surface morphology was investigated by scanning electron microscopy (SEM). Equilibrium swelling was measured in water at two different pH values and in vitro release of IbuNa in pH 1.2 and pH 7.4 media was studied. The release experiments revealed that drug release is pH sensitive. The release kinetics of IbuNa could be described by the Fickian model of diffusion with a good agreement. The IbuNa release rate was decreasing for all the films as the BC concentration was increased in the films composition, the decrease being higher for the multilayer films. PMID:24769089
Pavaloiu, Ramona-Daniela; Stoica-Guzun, Anicuta; Stroescu, Marta; Jinga, Sorin Ion; Dobre, Tanase
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
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
In the present study, a cross-sectional survey of intestinal parasitic and bacterial infections in relation to diarrhoea in Vhembe district and the antimicrobial susceptibility profiles of isolated bacterial pathogens was conducted. Stool samples were collected from 528 patients attending major public hospitals and 295 children attending two public primary schools and were analyzed by standard microbiological and parasitological techniques. Entamoeba histolytica/E. dispar (34.2%) and Cryptosporidium spp. (25.5%) were the most common parasitic causes of diarrhoea among the hospital attendees while Giardia lamblia (12.8%) was the most common cause of diarrhoea among the primary school children (p<0.05). Schistosoma mansoni (14.4%) was more common in non-diarrhoeal samples at both hospitals (16.9%) and schools (17.6%). Campylobacter spp. (24.9%), Aeromonas spp. (20.8%), and Shigella spp. (8.5%) were the most common bacterial causes of diarrhoea among the hospital attendees while Campylobacter (12.8%) and Aeromonas spp. (12.8%) were most common in diarrhoeal samples from school children. Vibrio spp. was less common (3% in the hospitals) and were all associated with diarrhoea. Antimicrobial resistance was common among the bacterial isolates but ceftriaxone (91%) and ciprofloxacin (88.6%) showed stronger activities against all the organisms. The present study has demonstrated that E. histolytica/dispar, Cryptosporidium, Giardia, and Cyclospora are common parasitic causes of diarrhoea in Vhembe district while Campylobacter spp. and Aeromonas are the most common bacterial causes of diarrhoea in Vhembe district of South Africa.
Guerrant, R.L.; Barrett, L.; Bessong, P.O.; Igumbor, E.O.; Obi, C.L.
AIM: To investigate the protective effect of glutamine (Gln) on intestinal injury and the bacterial community in rats exposed to hypobaric hypoxia environment. METHODS: Sprague-Dawley rats were divided into control, hypobaric hypoxia (HH), and hypobaric hypoxia + Gln (5.0 g/kg BW·d) (HG) groups. On the first 3 d, all rats were placed in a normal environment. After the third day, the HH and HG groups were transferred into a hypobaric chamber at a simulated elevation of 7000 m for 5 d. The rats in the HG group were given Gln by gavage daily for 8 d. The rats in the control and HH groups were treated with the same volume of saline. The intestinal morphology, serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), interleukin-6 (IL-6), tumor necrosis factor-? (TNF-?), interferon-gamma (IFN-?) and diamino oxidase (DAO) were examined. We also evaluated the expression levels of occludin, toll-like receptor 4 (TLR4), nuclear factor-?B p65 (NF-?B p65) and myeloid differentiation factor 88 (MyD88), and examined the bacterial community in caecal contents. RESULTS: Hypobaric hypoxia induced the enlargement of the heart, liver, lung and kidney, and caused spleen atrophy. Intestinal villi damage was also observed in the HH group. Supplementation with Gln significantly alleviated hypobaric-induced damage to main organs including the intestine, increased serum SOD (1.14 ± 0.03 vs 0.88 ± 0.04, P < 0.05) and MDA (8.35 ± 1.60, P < 0.01) levels and decreased serum IL-6 (1172.13±30.49 vs 1407.05 ± 34.36, P < 0.05), TNF-? (77.46 ± 0.78 vs 123.70 ± 3.03, P < 0.001), IFN-? (1355.42 ± 72.80 vs 1830.16 ± 42.07, P < 0.01) and DAO (629.30 ± 9.15 vs 524.10 ± 13.34, P < 0.001) levels. Moreover, Gln significantly increased occludin (0.72 ± 0.05 vs 0.09 ± 0.01, P < 0.001), TLR4 (0.15 ± 0.05 vs 0.30 ±0.09, P < 0.05), MyD88 (0.32 ± 0.08 vs 0.71 ± 0.06, P < 0.01), and NF-?B p65 (0.16 ± 0.04 vs 0.44 ± 0.03, P < 0.01) expression levels and improved the intestinal bacterial community. CONCLUSION: Gln treatment protects from intestinal injury and regulates the gut flora imbalance in hypoxia environment. These effects may be related to the TLR4/MyD88/NF-?B signaling pathway.
Xu, Chun-Lan; Sun, Rui; Qiao, Xiang-Jin; Xu, Cui-Cui; Shang, Xiao-Ya; Niu, Wei-Ning
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
AIM: To evaluate the protective effect and mechanism of glutamine on the intestinal barrier function in total parenteral nutrition (TPN) rats with trauma or endotoxemia. METHODS: To perform prospective, randomized and controlled animal experimentation of rats with surgical trauma, TPN and endotoxemia, thirty-four male, adult Sprague Dawley rats were divided into four groups: control group (n=8), TPN group (n=9), trauma
Lian-An Ding; Jie-Show Li
BACKGROUND: Celiac disease is a common cause of chronic diarrhea and malabsorption syndrome all over the world. Though it was considered uncommon in India in past, it is being described frequently recently. Some patients with celiac disease do not improve despite gluten free diet (GFD). A study described 15 cases of celiac disease unresponsive to GFD in whom small intestinal
Uday C Ghoshal; Ujjala Ghoshal; Asha Misra; Gourdas Choudhuri
T-helper-17 (TH17) cells have critical roles in mucosal defence and in autoimmune disease pathogenesis. They are most abundant in the small intestine lamina propria, where their presence requires colonization of mice with microbiota. Segmented filamentous bacteria (SFB) are sufficient to induce TH17 cells and to promote TH17-dependent autoimmune disease in animal models. However, the specificity of TH17 cells, the mechanism of their induction by distinct bacteria, and the means by which they foster tissue-specific inflammation remain unknown. Here we show that the T-cell antigen receptor (TCR) repertoire of intestinal TH17 cells in SFB-colonized mice has minimal overlap with that of other intestinal CD4(+) T cells and that most TH17 cells, but not other T cells, recognize antigens encoded by SFB. T cells with antigen receptors specific for SFB-encoded peptides differentiated into ROR?t-expressing TH17 cells, even if SFB-colonized mice also harboured a strong TH1 cell inducer, Listeria monocytogenes, in their intestine. The match of T-cell effector function with antigen specificity is thus determined by the type of bacteria that produce the antigen. These findings have significant implications for understanding how commensal microbiota contribute to organ-specific autoimmunity and for developing novel mucosal vaccines. PMID:24739972
Yang, Yi; Torchinsky, Miriam B; Gobert, Michael; Xiong, Huizhong; Xu, Mo; Linehan, Jonathan L; Alonzo, Francis; Ng, Charles; Chen, Alessandra; Lin, Xiyao; Sczesnak, Andrew; Liao, Jia-Jun; Torres, Victor J; Jenkins, Marc K; Lafaille, Juan J; Littman, Dan R
Suicide is a major public health problem in the United States as well as around the world. The significant role that alcohol plays in suicidality is well known and accepted in the scientific community. The use of alcohol does not necessarily lead to suicide, but through its action and effects, alcohol is an important proximal risk factor for suicidal behavior. There is very little data showing how and why alcohol exerts such tremendous influence and “lubricates the gears” to propel the act of committing suicide. This article will elucidate the complex relationship between alcohol and suicide and how alcohol use can lead to suicide. The article also describes how alcohol affects brain neurophysiology in regards to suicidal behavior.
Nathani, Milankumar; Jabeen, Shahgufta; Yazdani, Ijlal; Mouton, Charles D.; Bailey, Rahn K.; Mahr, Mona; Pate, Rebecca J.; Riley, Wayne J.
Background & Aims: No controlled trial has examined the clinical efficacy of antibiotics in small bowel bacterial overgrowth. Methods: Ten patients with bacterial overgrowth–related diarrhea underwent the following five 7-day treatment periods: untreated (control period), then placebo, and subsequently, in random order and blinded fashion, norfloxacin (800 mg\\/day), amoxicillin-clavulanic acid (1500 mg\\/day), and Saccharomyces boulardii (1500 mg\\/day). A hydrogen breath
Alain Attar; Bernard Flourié; Claire Franchisseur; Philippe Ruszniewski; Yoram Bouhnik
Infection of pancreatic necrosis by gut bacteria is a major cause of morbidity and mortality in patients with severe acute pancreatitis. Use of prophylactic antibiotics remains controversial. The aim of this experiment was assess if modification of intestinal flora with specifically designed multispecies probiotics reduces bacterial translocation or improves outcome in a rat model of acute pancreatitis. METHODS: Male Sprague-Dawley
L. Paul van Minnen; Harro M. Timmerman; Femke Lutgendorff; André Verheem; Wil Harmsen; Sergey R. Konstantinov; Hauke Smidt; Maarten R. Visser; Ger T. Rijkers; Hein G. Gooszen; Louis M. A. Akkermans
Background\\/Aims: Culture of small bowel aspirate is the most direct method and the gold standard for diagnosing small intestinal bacterial overgrowth. However, cultures are cumbersome and fluoroscopy is required for obtaining aspirate. Therefore, different breath tests such as the xylose breath test and the hydrogen breath test have been developed. There is no general agreement as to which test is
Per-Ove Stotzer; Anders F. Kilander
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
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
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
CD98 is a type II transmembrane glycoprotein whose expression increases in intestinal epithelial cells (IECs) during intestinal inflammation. Enteropathogenic Escherichia coli (EPEC) is a food-borne human pathogen that attaches to IECs and injects effector proteins directly into the host cells, thus provoking an inflammatory response. In the present study, we investigated CD98 and EPEC interactions in vitro and ex vivo and examined FVB wild-type (WT) and villin-CD98 transgenic mice overexpressing human CD98 in IECs (hCD98 Tg mice) and infected with Citrobacter rodentium as an in vivo model. In vivo studies indicated that CD98 overexpression, localized to the apical domain of colonic cells, increased the attachment of C. rodentium in mouse colons and resulted in increased expression of proinflammatory markers and decreased expression of anti-inflammatory markers. The proliferative markers Ki-67 and cyclin D1 were significantly increased in the colonic tissue of C. rodentium-infected hCD98 Tg mice compared to that of WT mice. Ex vivo studies correlate with the in vivo data. Small interfering RNA (siRNA) studies with Caco2-BBE cells showed a decrease in adherence of EPEC to Caco2 cells in which CD98 expression was knocked down. In vitro surface plasmon resonance (SPR) experiments showed direct binding between recombinant hCD98 and EPEC/C. rodentium proteins. We also demonstrated that the partial extracellular loop of hCD98 was sufficient for direct binding to EPEC/C. rodentium. These findings demonstrate the importance of the extracellular loop of CD98 in the innate host defense response to intestinal infection by attaching and effacing (A/E) pathogens.
Laroui, Hamed; Liu, Hongchun; Viennois, Emilie; Ayyadurai, Saravanan; Xiao, Bo; Ingersoll, Sarah A.; Kalman, Daniel; Merlin, Didier
The study revealed the possibility, on principle, for L. acidophilus strain VKM V-2020 D to colonize the intestine of white mice with the preservation of the viability of lactobacilli subjected to the action of antibiotics. The culture of this strain, isolated from the animals, showed the stability of its biological properties: resistance to polymyxin M, kanamycin, cyprofloxacin, nalidixic acid (including acquired resistance to rifampicin), as well as pronounced antagonism with respect to Vibrio cholerae. Good prospects for the use of L. acidophilus strain VKM V-2020 D for further studies regarding its use for prophylaxis and therapy were noted. PMID:9221664
Kruglikov, V D; Tsuraeva, R I; Ryzhko, I V; Drobotkovskaia, N V; Kuchin, V V; Bardykh, I D; Pushkareva, N D
Sequential interpenetrating network (IPN) of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) were prepared and crosslinked with glutaraldehyde (GA) to form pH-sensitive microspheres by the water-in-oil (w\\/o) emulsification method. Microspheres were used to deliver a model anti-inflammatory drug, diclofenac sodium (DS), to the intestine. The formed IPN was analyzed by Fourier transform infrared spectroscopy (FTIR). Differential scanning calorimetry (DSC) and
Mahaveer D Kurkuri; Tejraj M Aminabhavi
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
Defense against attaching and effacing (A/E) bacteria requires the sequential generation of interleukin 23 (IL-23) and IL-22 to induce protective mucosal responses. While CD4+ and NKp46+ innate lymphoid cells (ILCs) are the critical source of IL-22 during infection, the precise source of IL-23 is unclear. We used genetic techniques to deplete specific subsets of classical dendritic cells (cDCs) and analyzed immunity to the A/E pathogen Citrobacter rodentium. We found that Notch2 controlled the terminal stage of cDC differentiation. Notch2-dependent intestinal CD11b+ cDCs, but not Batf3-dependent CD103+ cDCs, were an obligate source of IL-23 required to survive C. rodentium infection. These results provide the first demonstration of a non-redundant function of CD11b+ cDCs in response to pathogens in vivo.
Satpathy, Ansuman T.; Briseno, Carlos G.; Lee, Jacob S.; Ng, Dennis; Manieri, Nicholas A.; KC, Wumesh; Wu, Xiaodi; Thomas, Stephanie R.; Lee, Wan-Ling; Turkoz, Mustafa; McDonald, Keely G.; Meredith, Matthew M.; Song, Christina; Guidos, Cynthia J.; Newberry, Rodney D.; Ouyang, Wenjun; Murphy, Theresa L.; Stappenbeck, Thaddeus S.; Gommerman, Jennifer L.; Nussenzweig, Michel C.; Colonna, Marco; Kopan, Raphael; Murphy, Kenneth M.
Campylobacter jejuni is the most prevalent cause of food-borne gastroenteritis in the developed world; however, the molecular basis of pathogenesis is unclear. Secretion of virulence factors is a key mechanism by which enteric bacterial pathogens interact with host cells to enhance survival and/or damage the host. However, C. jejuni lacks the virulence-associated secretion systems possessed by other enteric pathogens. Many bacterial pathogens utilize outer membrane vesicles (OMVs) for delivery of virulence factors into host cells. In the absence of prototypical virulence-associated secretion systems, OMVs could be an important alternative for the coordinated delivery of C. jejuni proteins into host cells. Proteomic analysis of C. jejuni 11168H OMVs identified 151 proteins, including periplasmic and outer membrane-associated proteins, but also many determinants known to be important in survival and pathogenesis, including the cytolethal distending toxin (CDT). C. jejuni OMVs contained 16 N-linked glycoproteins, indicating a delivery mechanism by which these periplasm-located yet immunogenic glycoproteins can interact with host cells. C. jejuni OMVs possess cytotoxic activity and induce a host immune response from T84 intestinal epithelial cells (IECs), which was not reduced by OMV pretreatment with proteinase K or polymyxin B prior to coincubation with IECs. Pretreatment of IECs with methyl-beta-cyclodextrin partially blocks OMV-induced host immune responses, indicating a role for lipid rafts in host cell plasma membranes during interactions with C. jejuni OMVs. OMVs isolated from a C. jejuni 11168H cdtA mutant induced interleukin-8 (IL-8) to the same extent as did wild-type OMVs, suggesting OMV induction of IL-8 is independent of CDT.
Elmi, Abdi; Watson, Eleanor; Sandu, Pamela; Gundogdu, Ozan; Mills, Dominic C.; Inglis, Neil F.; Manson, Erin; Imrie, Lisa; Bajaj-Elliott, Mona; Wren, Brendan W.; Smith, David G. E.
Several anaerobic bacteria from the human intestinal tract are capable of reducing azo dyes and nitropolycyclic aromatic hydrocarbons to the corresponding aromatic amines with enzymes that have azoreductase and nitroreductase activities. The majority of bacteria with these activities belong to the genera Clostridium and Eubacterium. The azoreductases and nitroreductases from three Clostridium strains and one Eubacterium strain were studied. Both enzymes were produced constitutively in each of the bacteria; the enzymes from various bacteria had different electrophoretic mobilities. The azoreductases from all of the bacteria had immunological homology, as was evident from the cross-reactivity of an antibody raised against the azoreductase of C. perfringens with azoreductases from other bacteria. Comparison of azoreductases and nitroreductases showed that they both had identical electrophoretic mobilities on polyacrylamide gels and reacted with the antibody against the azoreductase from C. perfringens. Furthermore, the nitroaromatic compounds competitively inhibited the azoreductase activity. The data indicate that the reduction of both nitroaromatic compounds and azo dyes may be carried out by the same enzyme, which is possibly a flavin adenine dinucleotide dehydrogenase that is synthesized throughout the cell and not associated with any organized subcellular structure. Images Figure 1.
Rafii, F; Cerniglia, C E
Immunostimulators recommended case secondary (acquired) immunodeficiency invasions helmints bacterial viral infections disorders nutrient resorbtion deficiency intestine kidney functions diabetes after narcosis burns after treatment Ionizing radiation other adverse environmental effects
Did you mean: Immunostimulators recommended case secondary (acquired) immunodeficiency invasions helmints bacterial viral infections disorders nutrient resorbtion deficiency intestine kidney functions diabetes after narcosis burns after treatment Ionizing radiation other adverse environmental effects ?
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
The bacterial communities in the intestinal tracts of earthworm were investigated by culture-dependent and - independent approaches. In total, 72 and 55 pure cultures were isolated from the intestinal tracts of earthworms under aerobic and anaerobic conditions, respectively. Aerobic bacteria were classified as Aeromonas (40%), Bacillus (37%), Photobacterium (10%), Pseudomonas (7%), and Shewanella (6%). Anaerobic bacteria were classified as Aeromonas (52%), Bacillus (27%), Shewanella (12%), Paenibacillus (5%), Clostridium (2%), and Cellulosimicrobium (2%). The dominant microorganisms were Aeromonas and Bacillus species under both aerobic and anaerobic conditions. In all, 39 DNA fragments were identified by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Aeromonas sp. was the dominant microorganism in feeds, intestinal tracts, and casts of earthworms. The DGGE band intensity of Aeromonas from feeds, intestinal tracts, and casts of earthworms was 12.8%, 14.7%, and 15.1%, respectively. The other strains identified were Bacillus, Clostridium, Enterobacter, Photobacterium, Pseudomonas, Shewanella, Streptomyces, uncultured Chloroflexi bacterium, and uncultured bacterium. These results suggest that PCR-DGGE analysis was more efficient than the culture-dependent approach for the investigation of bacterial diversity and the identification of unculturable microorganisms. PMID:21952364
Hong, Sung Wook; Kim, In Su; Lee, Ju Sam; Chung, Kun Sub
This prospective study examined bacterial colonization on writing pens touched by healthcare professionals and hospitalized patients with and without cleaning the pen with alcohol-based hand sanitizing agent after each patient visit. A significant reduction in potential healthcare-associated pathogens, especially Gram-positive cocci, was observed in the intervention group. PMID:21463395
Halton, K; Arora, V; Singh, V; Ghantoji, S S; Shah, D N; Garey, K W
In this study, a polymeric aortic heart valve made of poly(vinyl alcohol) (PVA)-bacterial cellulose (BC) nanocomposite is simulated and designed using a hyperelastic non-linear anisotropic material model. A novel nanocomposite biomaterial combination of 15 wt % PVA and 0.5 wt % BC is developed in this study. The mechanical properties of the synthesized PVA-BC are similar to those of the porcine heart valve in both the principal directions. To design the geometry of the leaflets an advance surfacing technique is employed. A Galerkin-based non-linear finite element method is applied to analyse the mechanical behaviour of the leaflet in the closing and opening phases under physiological conditions. The model used in this study can be implemented in mechanical models for any soft tissues such as articular cartilage, tendon, and ligament. PMID:19743636
Mohammadi, H; Boughner, D; Millon, L E; Wan, W K
Intestinal epithelial cells respond to Salmonella typhimurium by internalizing this pathogen and secreting, in a polarized manner, an array of chemokines which direct polymorphonuclear leukocyte (PMN) movement. Notably, interleukin-8 (IL-8) is secreted basolaterally and directs PMN through the lamina propria, whereas pathogen-elicited epithelial chemoattractant (PEEC) is secreted apically and directs PMN migration across the epithelial monolayer to the intestinal lumen.
ANDREW T. GEWIRTZ; ANDREW M. SIBER; JAMES L. MADARA; BETH A. MCCORMICK
Background and aims: The mechanisms by which commensal bacteria provoke intestinal inflammation in animal models of inflammatory bowel disease (IBD) remain incompletely defined, leading to increasing interest in the innate immune response of the colonic mucosa to bacterial colonisation. Methods: Using gene expression profiling of colonic RNA from C.B17.SCID germ free mice and those colonised with altered Schaedler’s flora, we investigated the innate immune response to bacterial colonisation in vivo. The two most consistently induced gene groups were RegIII? and ? as well as interferon ? (IFN-?) response genes. Results: Using quantitative reverse transcription-polymerase chain reaction, we showed that RegIII?, RegIII?, and IFN-? were constitutively expressed in the colon of conventionally housed SCID mice compared with either germ free SCID or conventionally housed BALB/c mice. Induction of these genes was reproduced by chronic monoassociation of germ free SCID mice with either of two separate gut commensal bacterial species—segmented filamentous bacteria and Schaedler’s Escherichia coli. The cellular source for IFN-? on monoassociation of SCID mice with Schaedler’s E coli was localised to a subset of intraepithelial natural killer (IENK) cells that express asialo-GM1. In vivo IFN-? immunoneutralisation studies failed to demonstrate any alteration in RegIII? or ? expression. Conclusions: Thus bacterial colonisation of the colon independently activates two distinct innate immune cell types at the mucosal interface with the colonic lumen, intestinal epithelial cells, and IENK cells, a response that may be regulated by the adaptive immune system. These innate immune responses may play a role in the pathogenesis of colitis in SCID adoptive transfer models in mice and possibly in patients with IBD.
Keilbaugh, S A; Shin, M E; Banchereau, R F; McVay, L D; Boyko, N; Artis, D; Cebra, J J; Wu, G D
The pervaporative (PV) performance with respect to the separation of ethanol\\/water (EtOH\\/H2O) azeotrope was assessed for a bacterial cellulose membrane (BCM) impregnated with chitosan (CTSN), designated as CTSN–BCM. The PV potential of CTSN–BCM was compared with that of parent polymers and also with the blends of CTSN with poly(vinyl alcohol) (PVA). The blends and CTSN–BCM were characterized using spectroscopic and
Vinita Dubey; Lokesh Kumar Pandey; Chhaya Saxena
Microbial penetration of the intestinal epithelial barrier triggers inflammatory responses that include induction of the bactericidal C-type lectin RegIII?. Systemic administration of flagellin, a bacterial protein that stimulates Toll-like receptor 5 (TLR5), induces epithelial expression of RegIII? and protects mice from intestinal colonization with antibiotic-resistant bacteria. Flagellin-induced RegIII? expression is IL-22 dependent, but how TLR signaling leads to IL-22 expression is incompletely defined. By using conditional depletion of lamina propria dendritic cell (LPDC) subsets, we demonstrated that CD103(+)CD11b(+) LPDCs, but not monocyte-derived CD103(-)CD11b(+) LPDCs, expressed high amounts of IL-23 after bacterial flagellin administration and drove IL-22-dependent RegIII? production. Maximal expression of IL-23 subunits IL-23p19 and IL-12p40 occurred within 60 min of exposure to flagellin. IL-23 subsequently induced a burst of IL-22 followed by sustained RegIII? expression. Thus, CD103(+)CD11b(+) LPDCs, in addition to promoting long-term tolerance to ingested antigens, also rapidly produce IL-23 in response to detection of flagellin in the lamina propria. PMID:22306017
Kinnebrew, Melissa A; Buffie, Charlie G; Diehl, Gretchen E; Zenewicz, Lauren A; Leiner, Ingrid; Hohl, Tobias M; Flavell, Richard A; Littman, Dan R; Pamer, Eric G
Graber, C. D. (Baylor University College of Medicine, Houston, Tex.). R. W. Moore, M. Suzuki, W. E. Redmond, R. M. O'Neal, and B. M. Lockhart. Autochthonous intestinal bacterial flora and cholesterol levels in specific pathogen-free swine fed high-lipid and high-sucrose diets. J. Bacteriol. 92:1290–1297. 1966.—Thirty-two specific pathogen-free (SPF) and conventional swine fed high fat, high sugar, and a standard ration were cultured for intestinal flora, and their blood cholesterol levels were measured. The diets, whether sterilized or not sterilized, fed ad libitum or restricted, did not alter bacterial flora greatly or influence blood cholesterol levels. Anaerobes outnumbered aerobes by several logs. Four autochthonous bacteria, lactobacilli, Escherichia coli, enterococci, and gram-variable, nonspore-forming anaerobes (GVNSA; a type of bacteroides), were shown to be constantly present in all animals regardless of dietary conditions. From the duodenum and jejunum of 14 pigs, GVNSA and Bacteroides nigrescens were cultured in rather large numbers, a finding not previously reported in swine or in most other mammals. This finding may have special significance in reference to bile acid and cholesterol metabolism.
Graber, C. D.; Moore, R. W.; Suzuki, M.; Redmond, W. E.; O'Neal, R. M.; Lockhart, B. M.
The high mortality commonly observed during the early life stages of intensively reared halibut (Hippoglossus hippoglossus L) is believed to be caused by e.g. opportunistic bacteria. However, the impact of particular bacterial species is poorly defined and still remains disputable. The study describes the bacterial diversity in the gastrointestinal tract of halibut larvae in a large number of incubators at
Rannveig Bjornsdottir; Jonina Johannsdottir; Jennifer Coe; Heiddis Smaradottir; Thorleifur Agustsson; Sjofn Sigurgisladottir; Bjarnheidur K. Gudmundsdottir
\\u000a The human gastrointestinal tract typically contains 300–500 bacterial species. Most bacterial species are acquired during\\u000a the birth process and although some changes to the flora may occur during later stages of life, the composition of the intestinal\\u000a microflora remains relatively constant. Small bowel bacterial overgrowth (SBBO) is defined as an excessive increase in the\\u000a number of bacteria in the upper
Rosemary J. Young; Jon A. Vanderhoof
In twelve patients with culture-proven bacterial overgrowth of the small intestine, the ability of a newly-developed one-gramd-[14C]xylose breath test to detect bacterial overgrowth was compared to that of the [14C]bile acid breath test. All patients manifested excessive production of breath14CO2 after the administration of one gram [14C]xylose, with 83% of the patients being abnormal within the first hour of testing.
Charles E. King; Phillip P. Toskes; Tomas R. Guilarte; Erhard Lorenz; Susan L. Welkos
We investigated the influence of various substrates on the uptake of long-chain fatty acid into IEC-6, rat intestinal epithelial\\u000a cell line. The uptake of [3H]oleic acid into IEC-6 cells was a saturable function of the oleic acid concentration. Long-chain fatty acids significantly\\u000a inhibited the oleic acid uptake into IEC-6 cells and shorter-chain fatty acids had little or no effect. Various
Kaeko Murota; Noriko Matsui; Teruo Kawada; Nobuyuki Takahashi; Takafumi Shintani; Kahori Sasaki; Tohru Fushiki
Failure of the intestinal barrier is a characteristic feature of cholestasis. We have previously observed higher mortality in C57BL/6J compared with A/J mice following common bile duct ligation (CBDL). We hypothesized the alteration in gut barrier function following cholestasis would vary by genetic background. Following one week of CBDL, jejunal TEER was significantly reduced in each ligated mouse compared with their sham counterparts; moreover, jejunal TEER was significantly lower in both sham and ligated C57BL/6J compared with sham and ligated A/J mice, respectively. Bacterial translocation to mesenteric lymph nodes was significantly increased in C57BL/6J mice vs. A/J mice. Four of 15 C57BL/6J mice were bacteremic; whereas, none of the 17 A/J mice were. Jejunal IFN-? mRNA expression was significantly elevated in C57BL/6J compared with A/J mice. Western blot analysis demonstrated a significant decrease in occludin protein expression in C57BL/6J compared with A/J mice following both sham operation and CBDL. Only C57BL/6J mice demonstrated a marked decrease in ZO-1 protein expression following CBDL compared with shams. Pyrosequencing of the 16S rRNA gene in fecal samples showed a dysbiosis only in C57BL/6J mice following CBDL when compared with shams. This study provides evidence of strain differences in gut microbiota, tight junction protein expression, intestinal resistance and bacterial translocation which supports the notion of a genetic predisposition to exaggerated injury following cholestasis.
Alaish, Samuel M.; Smith, Alexis D.; Timmons, Jennifer; Greenspon, Jose; Eyvazzadeh, Daniel; Murphy, Ebony; Shea-Donahue, Terez; Cirimotich, Shana; Mongodin, Emmanuel; Zhao, Aiping; Fasano, Alessio; Nataro, James P.; Cross, Alan S
Failure of the intestinal barrier is a characteristic feature of cholestasis. We have previously observed higher mortality in C57BL/6J compared with A/J mice following common bile duct ligation (CBDL). We hypothesized the alteration in gut barrier function following cholestasis would vary by genetic background. Following one week of CBDL, jejunal TEER was significantly reduced in each ligated mouse compared with their sham counterparts; moreover, jejunal TEER was significantly lower in both sham and ligated C57BL/6J compared with sham and ligated A/J mice, respectively. Bacterial translocation to mesenteric lymph nodes was significantly increased in C57BL/6J mice vs. A/J mice. Four of 15 C57BL/6J mice were bacteremic; whereas, none of the 17 A/J mice were. Jejunal IFN-? mRNA expression was significantly elevated in C57BL/6J compared with A/J mice. Western blot analysis demonstrated a significant decrease in occludin protein expression in C57BL/6J compared with A/J mice following both sham operation and CBDL. Only C57BL/6J mice demonstrated a marked decrease in ZO-1 protein expression following CBDL compared with shams. Pyrosequencing of the 16S rRNA gene in fecal samples showed a dysbiosis only in C57BL/6J mice following CBDL when compared with shams. This study provides evidence of strain differences in gut microbiota, tight junction protein expression, intestinal resistance and bacterial translocation which supports the notion of a genetic predisposition to exaggerated injury following cholestasis. PMID:23652772
Alaish, Samuel M; Smith, Alexis D; Timmons, Jennifer; Greenspon, Jose; Eyvazzadeh, Daniel; Murphy, Ebony; Shea-Donahue, Terez; Cirimotich, Shana; Mongodin, Emmanuel; Zhao, Aiping; Fasano, Alessio; Nataro, James P; Cross, Alan
Carboxymethylcellulase (CMCase)-producing obligate anaerobes were isolated from the intestinal tract contents but not the feeding habitat of seagrass-consuming pinfish. Taxonomic characterization of these CMCase-producing strains revealed four taxonomic clusters; three were clostridial and one was of unknown taxonomic affinity. Our results demonstrated that the CMCase-producing obligate anaerobe community from pinfish differed from functionally similar microbial communities in terrestrial herbivores.
Stellwag, E. J.; Smith, T. D.; Luczkovich, J. J.
Background & Aims: In experimental animals, the indigenous microbiota modulates mucosal immunity. In humans, such direct evidence is scarce. The aim of this study was to examine the effect of intestinal bacteria on the local immunoglobulin (Ig) response. Methods: The numbers of IgA-, IgM-, and IgG-producing immunocytes per defined mucosal length unit were determined, and the local IgA subclass response
Kjell Kett; Kåre Baklien; Arne Bakken; John G. Kral; Olav Fausa; Per Brandtzaeg
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
Using morphological analysis and biochemical testing, here for the first time, we determined the culturable gut bacterial flora (aerobes and facultative anaerobes) in the venomous Black Cobra (Naja naja karachiensis) from South Asia. The findings revealed that these snakes inhabit potentially pathogenic bacteria including Serratia marcescens, Pseudomonas aeruginosa, Shewanella putrefaciens, Aeromonas hydrophila, Salmonella sp., Moraxella sp., Bacillus sp., Ochrobactrum anthropi, and Providencia rettgeri. These findings are of concern, as injury from snake bite can result in wound infections and tissue necrosis leading to sepsis/necrotizing fasciitis and/or expose consumers of snake meat/medicine in the community to infections. PMID:25002979
Iqbal, Junaid; Sagheer, Mehwish; Tabassum, Nazneen; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed
Using morphological analysis and biochemical testing, here for the first time, we determined the culturable gut bacterial flora (aerobes and facultative anaerobes) in the venomous Black Cobra (Naja naja karachiensis) from South Asia. The findings revealed that these snakes inhabit potentially pathogenic bacteria including Serratia marcescens, Pseudomonas aeruginosa, Shewanella putrefaciens, Aeromonas hydrophila, Salmonella sp., Moraxella sp., Bacillus sp., Ochrobactrum anthropi, and Providencia rettgeri. These findings are of concern, as injury from snake bite can result in wound infections and tissue necrosis leading to sepsis/necrotizing fasciitis and/or expose consumers of snake meat/medicine in the community to infections.
Iqbal, Junaid; Sagheer, Mehwish; Tabassum, Nazneen; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed
Recognition of repeat CpG motifs, which are common in bacterial, but not in mammalian, DNA, through Toll-like receptor (TLR)9 is an integral part of the innate immune system. As the role of TLR9 in the human gut is unknown, we determined the spectrum of TLR9 expression in normal and inflamed colon and examined how epithelial cells respond to specific TLR9 ligand stimulation. TLR9 expresssion was measured in human colonic mucosal biopsies, freshly isolated human colonic epithelial cells and HT-29 cells by reverse transcriptase-polymerase chain reaction or Western blotting. Colonic epithelial cell cultures were stimulated with a synthetic CpG-oligodeoxynucleotide (ODN), exhibiting strong immunostimulatory effects in B cells. Interleukin (IL)-8 secretion was determined by enzyme-linked immunosorbent assay, nuclear factor-kappaB (NF-kB) activity by electrophoretic mobility shift assay and IkB phosphorylation by Western blotting. TLR9 mRNA was equally expressed in colonic mucosa from controls (n = 6) and patients with ulcerative colitis or Crohn's disease disease (n = 13). HT-29 cells expressed TLR9 mRNA and protein and responded to CpG-ODN (P < 0·01), but not to non-CpG-ODN stimulation, by secreting IL-8, apparently in the absence of NF-kB activation. Primary epithelial cells isolated from normal human colon expressed TLR9 mRNA, but were completely unresponsive to CpG-ODN stimulation in vitro. In conclusion, differentiated human colonic epithelial cells are unresponsive to TLR9 ligand stimulation in vitro despite spontaneous TLR9 gene expression. This suggests that the human epithelium is able to avoid inappropriate immune responses to luminal bacterial products through modulation of the TLR9 pathway.
Pedersen, G; Andresen, L; Matthiessen, M W; Rask-Madsen, J; Brynskov, J
The surface flora of the antecubital fossa (ACF) of 25 subjects comprised the same kinds of bacteria as are commonly found on the hands, arms, back and forehead. The population density was bimodal. Fifteen subjects had a sparse flora. After alcohol disinfection there were no surviving bacteria on these subjects. The other 10 subjects had a more abundant flora (310
Charles A. Evans; Kathy L. Mattern
The probiotic Escherichia coli strain Nissle 1917 (Mutaflor) of serotype O6:K5:H1 was reported to protect gnotobiotic piglets from infection with Salmonella enterica serovar Typhimurium. An important virulence property of Salmonella is invasion of host epithelial cells. Therefore, we tested for interference of E. coli strain Nissle 1917 with Salmonella invasion of INT407 cells. Simultaneous administration of E. coli strain Nissle 1917 and Salmonella resulted in up to 70% reduction of Salmonella invasion efficiency. Furthermore, invasion of Yersinia enterocolitica, Shigella flexneri, Legionella pneumophila and even of Listeria monocytogenes were inhibited by the probiotic E. coli strain Nissle 1917 without affecting the viability of the invasive bacteria. The observed inhibition of invasion was not due to the production of microcins by the Nissle 1917 strain because its isogenic microcin-negative mutant SK22D was as effective as the parent strain. Reduced invasion rates were also achieved if strain Nissle 1917 was separated from the invasive bacteria as well as from the INT407 monolayer by a membrane non-permeable for bacteria. We conclude E. coli Nissle 1917 to interfere with bacterial invasion of INT407 cells via a secreted component and not relying on direct physical contact with either the invasive bacteria or the epithelial cells. PMID:15039098
Altenhoefer, Artur; Oswald, Sibylle; Sonnenborn, Ulrich; Enders, Corinne; Schulze, Juergen; Hacker, Joerg; Oelschlaeger, Tobias A
Xanthan gum (XG), a trisaccharide branched polymer and poly vinyl alcohol (PVA), was used to develop pH-sensitive interpenetrating network (IPN) microspheres by emulsion cross-linking method in the presence of glutaraldehyde as a cross-linker to deliver model anti-inflammatory drug, diclofenac sodium (DS) to the intestine. Various formulations were prepared by changing the ratio of XG:PVA, extent of cross-linking in order to optimize the formulation variables on drug encapsulation efficiency, and release rate. Formation of interpenetrating network and the chemical stability of DS after penetration of microspheres was confirmed by Fourier Transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis were done on the drug loaded microspheres which confirmed molecular dispersion of DS in the IPN. Microspheres formed were spherical with smooth surfaces, as evidenced by scanning electron microscopy (SEM), and mean particle size, as measured by laser light scattering technique ranged between 310.25-477.10 microm. Drug encapsulation of up to 82.94% was achieved as measured by UV method. Both equilibrium and dynamic swelling studies and in vitro release studies were performed in pH 1.2 and 6.8. Release data indicated a Fickian trend of drug release which depends on the extent of cross-linking and the ratio of XG:PVA present in the microsphere. When subjected to in vivo pharmacokinetic evaluation in rabbits, microparticles show slow and prolonged drug release when compared with DS solution. Based on the results of in vitro and in vivo studies it was concluded that these IPN microspheres provided oral controlled release of water-soluble DS. PMID:20482471
Ray, Somasree; Banerjee, Subham; Maiti, Sabyasachi; Laha, Bibek; Barik, Saikat; Sa, Biswanath; Bhattacharyya, Uttam Kumar
Aryl alcohol oxidase (AAO) produced by dye decolorizing bacteria Sphingobacterium sp. ATM, was purified 22.63 fold to a specific activity of 21.75 ?mol\\/min\\/mg protein using anion exchange and size exclusion\\u000a chromatography. The molecular weight of the purified AAO was found to be 71 kDa using sodium dodecyl sulfate polyacrylamide\\u000a gel electrophoresis (SDS-PAGE), and confirmed by zymography of AAO using L-dopa.
Dhawal P. Tamboli; Amar A. Telke; Vishal V. Dawkar; Shekhar B. Jadhav; Sanjay P. Govindwar
Bacterial translocation is defined as the passage of viable indigenous bacteria from the gastrointestinal tract to extraintestinal sites, such as the mesenteric-lymph-node complex, liver, spleen and bloodstream. Three major mechanisms promote bacterial translocation: intestinal bacterial overgrowth, deficiencies in host immune defenses and increased permeability or damage to the intestinal mucosal barrier.
Rodney D. Berg
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
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.
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;)
We assessed the bacterial contamination of the pagers of healthcare personnel and the efficacy of disinfection with 70% isopropyl alcohol. Microorganisms were isolated from all pagers; 21% yielded Staphylococcus aureus, of which 14% were methicillin resistant. Cleaning with alcohol reduced the total colony count by an average of 94%. Bacterial load varied by healthcare worker group and service assignment. PMID:12026153
Singh, Deepjot; Kaur, Hanspreet; Gardner, William G; Treen, Lisa B
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.
Interferon-gamma causes a global phenotypic switch in intestinal epithelial function, in which enterocytes become immune accessory cells. The phenotypic switch is characterized by a down-regulation of membrane transporters and up-regulation of immune accessory molecules in intestinal epithelial cells. However, the effect of interferon-gamma on the intestinal epithelia di-tripeptide hPepT1 transporter has not been investigated. In this study we demonstrate that 1) interferon-gamma increases di-tripeptide uptake in dose- and time-dependent manner in model intestinal epithelia (Caco-2 BBE cell monolayers), 2) the increase in di-tripeptides induced by interferon-gamma is hPepT1 mediated, 3) interferon-gamma does not affect the hPept1 expression at the mRNA and protein levels 4) interferon-gamma increases the intracellular pH and consequently enhances the H+-electrochemical gradient across apical plasma membrane in model intestinal epithelia (Caco2-BBE monolayers). We suggest that interferon-gamma could increase the hPepT1 mediated di-tripeptides uptake in inflamed epithelial cells. Under these conditions, interferon-gamma will increase the intracellular amount of such diverse prokaryotic and eucaryotic small di-tripeptides in inflamed epithelial cells. The intracellular accumulation of such di-tripeptides may be important in enterocytes becoming immune accessory cells. PMID:14578196
Buyse, Marion; Charrier, Laetitia; Sitaraman, Shanthi; Gewirtz, Andrew; Merlin, Didier
A great number of epidemiological data have identified chronic alcohol consumption as a significant risk factor for upper\\u000a alimentary tract cancer, including cancer of the oropharynx, larynx, and the esophagus, and for the liver. In contrast to\\u000a those organs, the risk by which alcohol consumption increases cancer in the large intestine and in the breast is much smaller.\\u000a However, although
Helmut K. Seitz; Gudrun Pöschl; Ulrich A. Simanowski
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;)
Two experiments were conducted to determine the effect of sucrose thermal oligosaccharide caramel (STOC) and dietary vitamin-mineral (V\\/M) level on growth performance and intestinal microflora of broiler chickens. In Experiment 1, Peterson × Arbor Acres male broilers (n = 384) were randomly allocated into four groups that were fed either the control diet or diets containing the antibiotic virginiamycin (11
J. I. ORBAN; J. A. PATTERSON; A. L. SUTTON; G. N. RICHARDS
Alcohol and histamine metabolic pathways in the body have the common enzymes aldehyde dehydrogenase and aldehyde oxidase. The metabolite of ethanol, acetaldehyde, can effectively compete with the metabolites of histamine, methylimidazole acetaldehyde, and imidazole acetaldehyde. At the periphery, alcohol and acetaldehyde liberate histamine from its store in mast cells and depress histamine elimination by inhibiting diamine oxidase, resulting in elevated histamine levels in tissues. Histamine mediates alcohol-induced gastric and intestinal damage and bronchial asthma as well as flushing in Orientals. On the other hand, alcohol provokes food-induced histaminosis and histamine intolerance, which is an epidemiological problem. There are many controversial reports concerning the effect of H2 receptor antagonists on ethanol metabolism and the activity of alcohol dehydrogenase in the stomach. In addition, alcohol affects histamine levels in the brain by modulating histamine synthesis, release, and turnover. Histamine receptor antagonists can affect ethanol metabolism and change the sensitivity of animals to the hypnotic effects of alcohol. In contrast to other neurotransmitters, the involvement of the brain histamine system in the mechanisms of the central actions of alcohol and in the pathogenesis of alcoholism is poorly studied and understood. PMID:10344773
Zimatkin, S M; Anichtchik, O V
... as genes that protect against alcohol problems. The neural basis of alcohol dependence was clarified. Research showing that drinking is influenced by multiple neurotransmitter systems, neuromodulators, hormones, and intracellular networks provides evidence of a number of potential target ...
Describes research on synergistic effects of alcohol and other drugs, particularly barbiturates. Proposes biochemical mechanisms to explain alcoholics' tolerance of other drugs when sober, and increased sensitivity when drunk. (AL)
Rubin, Emanuel; Lieber, Charles S.
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.
Characterization of an Escherichia coli O157:H7 O-Antigen Deletion Mutant and Effect of the Deletion on Bacterial Persistence in the Mouse Intestine and Colonization at the Bovine Terminal Rectal Mucosa?
Escherichia coli O157:H7 causes hemorrhagic colitis and the life-threatening hemolytic-uremic syndrome in humans and transiently colonizes healthy cattle at the terminal rectal mucosa. To investigate the role of the O antigen in persistence and colonization in the animal host, we generated an E. coli O157:H7 mutant defective in the synthesis of the lipopolysaccharide side chain (O antigen) by deletion of a putative perosamine synthetase gene (per) in the rfb cluster. The lack of O antigen was confirmed by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and anti-O157 antibody. The growth rate and cell membrane permeability of the ?per mutant were similar to the growth rate and cell membrane permeability of the wild type. Changes in membrane and secreted proteins were observed, but the expression of intimin, EspA, and EspB, implicated in bacterial intestinal colonization, was not altered, as determined by immunoblotting and reverse transcription-PCR. Similar to other O-antigen deletion mutants, the ?per mutant was pleiotropic for autoaggregation and motility (it was FliC negative as determined by immunoblotting and flagellum negative as determined by electron microscopy). The abilities of the mutant and the wild type to persist in the murine intestine and to colonize the bovine terminal rectal mucosa were compared. Mice fed the ?per mutant shed lower numbers of bacteria (P < 0.05) over a shorter time than mice fed the wild-type or complemented strain. After rectal application in steers, lower numbers of the ?per mutant than of the wild type colonized the rectoanal junction mucosa, and the duration of the colonization was shorter (P < 0.05). Our previous work showed that flagella do not influence E. coli O157:H7 colonization at the bovine terminal rectal mucosa, so the current findings suggest that the O antigen contributes to efficient bovine colonization.
Sheng, Haiqing; Lim, Ji Youn; Watkins, Maryann K.; Minnich, Scott A.; Hovde, Carolyn J.
Intestinal transplantation is often the only alternative form of treatment for patients dependent on total parenteral nutrition for survival. Although a limited number of intestinal transplantations have been performed, results with FK 506 immunosuppression are comparable to those for other organ transplants. The impact of successful intestinal transplantation on gastroenterology will likely be similar to the impact of kidney and liver transplantation on nephrology and hepatology.
Tzakis, Andreas G.; Todo, Satoru; Starzl, Thomas E.
The normal indigenous intestinal microflora consists of about 1015 bacteria that under physiological conditions reside mainly in the lower gastrointestinal tract. Bacterial overgrowth implies abnormal bacterial colonization of the upper gut, resulting from failure of specific defense mechanisms restricting colonization under physiological conditions. At present two types of bacterial overgrowth with defined pathogenesis can be distinguished: (1) gastric overgrowth with
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.
The environmental contaminants which have their major effects on the small intestine may be classified into five major categories: (1) bacterial, viral, and parasitic agents, (2) food and plant substances, (3) environmental and industrial products, (4) pharmaceutical agents, and (5) toxic agents whose metabolic effects are dependent on interreaction with intestinal bacterial flora, other physical agents (detergents), human intestinal enzyme deficiency states, and the nutritional state of the host. Bacterial, viral, and parasitic agents are the most important of all such agents, being responsible for significant mortality and morbidity in association with diarrheal diseases of adults and children. Several plant substances ingested as foods have unique effects on the small bowel as well as from contaminants such as fungi on poorly preserved grains and cereals. Environmental and industrial products, in spite of their widespread prevalence in industrial societies as contaminants, are less important unless unexpectedly intense exposure occurs to the intestinal tract. Pharmaceutical agents of several types interreact with the small bowel mucosa causing impairment of transport processes for fluid and electrolytes, amino acid, lipid and sugars as well as vitamins. These interreactions may be dependent on bacterial metabolic activity, association with detergents, mucosal enzyme deficiency state (disaccharidases), and the state of nutrition of the subject.
Banwell, John G.
... tissue build-up after any type of abdominal surgery) could occur later. Children who require removal of a large portion of the small intestine can have too little bowel to maintain adequate nutrition (a condition known ... a time after surgery (or even permanently if too little intestine remains) ...
Two cases of intestinal spirochaetosis are described. The first case improved with treatment while the second case improved spontaneously without any intervention. Controversy over treatment and pathogenicity of intestinal spirochaetosis is discussed with review of previous publications. Images Figure 1 Figure 2 Figure 3
Lo, T. C.; Heading, R. C.; Gilmour, H. M.
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.
Parasitic nematodes are potent modulators of immune reactivity in mice and men. Intestinal nematodes live in close contact with commensal gut bacteria, provoke biased Th2 immune responses upon infection, and subsequently lead to changes in gut physiology. We hypothesized that murine nematode infection is associated with distinct changes of the intestinal bacterial microbiota composition. We here studied intestinal inflammatory and immune responses in mice following infection with the hookworm Heligmosomoides polygyrus bakeri and applied cultural and molecular techniques to quantitatively assess intestinal microbiota changes in the ileum, cecum and colon. At day 14 post nematode infection, mice harbored significantly higher numbers of ?-Proteobacteria/Enterobacteriaceae and members of the Bacteroides/Prevotella group in their cecum as compared to uninfected controls. Abundance of Gram-positive species such as Lactobacilli, Clostridia as well as the total bacterial load was not affected by worm infection. The altered microbiota composition was independent of the IL-4/-13 - STAT6 signaling axis, as infected IL-4R?(-/-) mice showed a similar increase in enterobacterial loads. In conclusion, infection with an enteric nematode is accompanied by distinct intestinal microbiota changes towards higher abundance of gram-negative commensal species at the small intestinal site of infection (and inflammation), but also in the parasite-free large intestinal tract. Further studies should unravel the impact of nematode-induced microbiota changes in inflammatory bowel disease to allow for a better understanding of how theses parasites interfere with intestinal inflammation and bacterial communities in men. PMID:24040152
Rausch, Sebastian; Held, Josephin; Fischer, André; Heimesaat, Markus M; Kühl, Anja A; Bereswill, Stefan; Hartmann, Susanne
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
Alcoholism results in about 2.5 million deaths annually worldwide, representing 4% of all mortality. Although alcoholism is associated with more than 60 diseases, most mortality from alcoholism results from alcoholic liver disease (ALD). ALD includes alcoholic steatosis, alcoholic hepatitis, and alcoholic cirrhosis, in order of increasing severity. Important scoring systems of ALD severity include: Child-Pugh, a semi-quantitative scoring system useful to roughly characterize clinical severity; model for end-stage liver disease, a quantitative, objective scoring system used for prognostication and prioritization for liver transplantation; and discriminant function, used to determine whether to administer corticosteroids for alcoholic hepatitis. Abstinence is the cornerstone of ALD therapy. Psychotherapies, including twelve-step facilitation therapy, cognitive-behavioral therapy, and motivational enhancement therapy, help support abstinence. Disulfiram decreases alcohol consumption by causing unpleasant sensations after drinking alcohol from accumulation of acetaldehyde in serum, but disulfiram can be hepatotoxic. Adjunctive pharmacotherapies to reduce alcohol consumption include naltrexone, acamprosate, and baclofen. Nutritional therapy helps reverse muscle wasting, weight loss, vitamin deficiencies, and trace element deficiencies associated with ALD. Although reduced protein intake was previously recommended for advanced ALD to prevent hepatic encephalopathy, a diet containing 1.2-1.5 g of protein/kg per day is currently recommended to prevent muscle wasting. Corticosteroids are first-line therapy for severe alcoholic hepatitis (discriminant function ? 32), but proof of their efficacy in decreasing mortality remains elusive. Pentoxifylline is an alternative therapy. Complications of advanced ALD include ascites, spontaneous bacterial peritonitis, esophageal variceal bleeding, hepatic encephalopathy, hepatorenal syndrome, hepatopulmonary syndrome, and portopulmonary hypertension. Alcoholic cirrhotics have increased risk of developing hepatomas. Liver transplantation is the ultimate therapy for severe ALD, but generally requires 6 mo of proven abstinence for eligibility. Alcoholic cirrhotics who maintain abstinence generally have a relatively favorable prognosis after liver transplantation.
Jaurigue, Maryconi M; Cappell, Mitchell S
Alcoholism results in about 2.5 million deaths annually worldwide, representing 4% of all mortality. Although alcoholism is associated with more than 60 diseases, most mortality from alcoholism results from alcoholic liver disease (ALD). ALD includes alcoholic steatosis, alcoholic hepatitis, and alcoholic cirrhosis, in order of increasing severity. Important scoring systems of ALD severity include: Child-Pugh, a semi-quantitative scoring system useful to roughly characterize clinical severity; model for end-stage liver disease, a quantitative, objective scoring system used for prognostication and prioritization for liver transplantation; and discriminant function, used to determine whether to administer corticosteroids for alcoholic hepatitis. Abstinence is the cornerstone of ALD therapy. Psychotherapies, including twelve-step facilitation therapy, cognitive-behavioral therapy, and motivational enhancement therapy, help support abstinence. Disulfiram decreases alcohol consumption by causing unpleasant sensations after drinking alcohol from accumulation of acetaldehyde in serum, but disulfiram can be hepatotoxic. Adjunctive pharmacotherapies to reduce alcohol consumption include naltrexone, acamprosate, and baclofen. Nutritional therapy helps reverse muscle wasting, weight loss, vitamin deficiencies, and trace element deficiencies associated with ALD. Although reduced protein intake was previously recommended for advanced ALD to prevent hepatic encephalopathy, a diet containing 1.2-1.5 g of protein/kg per day is currently recommended to prevent muscle wasting. Corticosteroids are first-line therapy for severe alcoholic hepatitis (discriminant function ? 32), but proof of their efficacy in decreasing mortality remains elusive. Pentoxifylline is an alternative therapy. Complications of advanced ALD include ascites, spontaneous bacterial peritonitis, esophageal variceal bleeding, hepatic encephalopathy, hepatorenal syndrome, hepatopulmonary syndrome, and portopulmonary hypertension. Alcoholic cirrhotics have increased risk of developing hepatomas. Liver transplantation is the ultimate therapy for severe ALD, but generally requires 6 mo of proven abstinence for eligibility. Alcoholic cirrhotics who maintain abstinence generally have a relatively favorable prognosis after liver transplantation. PMID:24605013
Jaurigue, Maryconi M; Cappell, Mitchell S
Human milk oligosaccharides (HMO) constitute the third most abundant class of molecules in breast milk. Since infants lack the enzymes required for milk glycan digestion, this group of carbohydrates passes undigested to the lower part of the intestinal tract, where they can be consumed by specific members of the infant gut microbiota. We review proposed mechanisms for the depletion and metabolism of HMO by two major bacterial genera within the infant intestinal microbiota, Bifidobacterium and Bacteroides
Marcobal, A.; Sonnenburg, J. L.
Although the knowledge of the effects of bacterial colonization on the immune system is rapidly expanding, surprisingly little\\u000a is known about the immunological mechanisms that shape the intestinal microbial community. Specifically, the complexity of\\u000a the intestinal microbiota and what constitutes a “healthy” microbial composition has only recently been addressed, facilitated\\u000a by large-scale metagenomic screens. Containment of such a vast number
Sylvia Brugman; Edward E. S. Nieuwenhuis
Neonatal necrotizing enterocolitis is a devastating inflammatory bowel disease of premature infants. The pathogenesis remains incompletely understood and there is no specific treatment. Efforts are ongoing to understand aspects of intestinal immaturity which contribute to susceptibility to this disease. This review focuses on bacterial colonization patterns, intestinal barrier function, and inflammatory responses of immature enterocytes leading to a unique vulnerability of the preterm gut. In addition the possible therapeutic potential of factors in human milk and probiotic bacteria is discussed.
Claud, Erika C.
Low–molecular-weight metabolites produced by intestinal microbiota play a direct role in health and disease. In this study, we analyzed the colonic luminal metabolome using capillary electrophoresis mass spectrometry with time-of-flight (CE-TOFMS) —a novel technique for analyzing and differentially displaying metabolic profiles— in order to clarify the metabolite profiles in the intestinal lumen. CE-TOFMS identified 179 metabolites from the colonic luminal metabolome and 48 metabolites were present in significantly higher concentrations and/or incidence in the germ-free (GF) mice than in the Ex-GF mice (p < 0.05), 77 metabolites were present in significantly lower concentrations and/or incidence in the GF mice than in the Ex-GF mice (p < 0.05), and 56 metabolites showed no differences in the concentration or incidence between GF and Ex-GF mice. These indicate that intestinal microbiota highly influenced the colonic luminal metabolome and a comprehensive understanding of intestinal luminal metabolome is critical for clarifying host-intestinal bacterial interactions.
Matsumoto, Mitsuharu; Kibe, Ryoko; Ooga, Takushi; Aiba, Yuji; Kurihara, Shin; Sawaki, Emiko; Koga, Yasuhiro; Benno, Yoshimi
Summary. Dietary carbohydrates that escape digestion in the small intestine, undergo bacterial fermentation in the colon. This process affects the microbial ecology of the gastrointestinal tract and influences gut metabolism and function. Prebiotics are non-digestible but fermentable oligosaccharides that are specifically designed to change the composition and activity of the intestinal microbiota with the prospect to promote the health of
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
We received 38 controlled studies of marital and family therapy (MFT) in alcoholism treatment. We conclude that, when the alcoholic is unwilling to seek help, MFT is effective in helping the family cope better and motivating alcoholics to enter treatment. Specifically, (a) Al-Anon facilitation and referral help family members cope better; (b)…
O'Farrell, Timothy J.; Fals-Stewart, William
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 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
Recognition of alcoholism as a treatable illness is a result of public education based on scientific facts. This publication, a digest of a more detailed survey of research about drinking and alcoholism, presents information about alcohol and its effects on individuals and society. It provides facts about the short-term and long-term effects of…
Hall, Leonard C.
The gastrointestinal tract is frequently challenged by pathogens/antigens contained in food and water and the intestinal epithelium must be capable of rapid regeneration in the event of tissue damage. Disruption of the intestinal barrier leads to a number of immune-mediated diseases, including inflammatory bowel disease, food allergy, and celiac disease. The intestinal mucosa is composed of different types of epithelial cells in specific barrier functions. Epithelial cells control surface-associated bacterial populations without disrupting the intestinal microflora that is crucial for host health. They are also capable of modulating mucosal immune system, and are thus essential in maintaining homeostasis in the gut. Thus, the regulation of intestinal epithelial homeostasis is crucial for the maintenance of the structure of the mucosa and the defensive barrier functions. Recent studies have demonstrated that multiple molecular pathways are involved in the regulation of intestinal epithelial cell polarity. These include the Wnt, Notch, Hippo, transforming growth factor-? (TGF-?)/bone morphogenetic protein (BMP) and Hedgehog pathways, most of which were identified in lower organisms where they play important roles during embryogenesis. These pathways are also used in adult organisms to regulate multiple self-renewing organs. Understanding the interactions between these molecular mechanisms and intestinal barrier function will therefore provide important insight into the pathogenesis of intestinal-based immune-mediated diseases.
Jeon, Min Kyung; Klaus, Christina; Kaemmerer, Elke; Gassler, Nikolaus
The non-aqueous use of ethanol or propanols offers various advantages over washing hands with either unmedicated or medicated soap in both hygienic and surgical hand disinfection. Alcohols exert the strongest and fastest activity against a wide spectrum of bacteria and fungi (but not bacterial spores) as well as enveloped (but less so against non-enveloped) viruses, being little influenced by interfering
M. L. Rotter
The human endogenous intestinal microflora is an essential ``organ'' in providing nourishment, regulating epithelial development, and instructing innate immunity; yet, surprisingly, basic features remain poorly described. We examined 13,355 prokaryotic ribosomal RNA gene sequences from multiple colonic mucosal sites and feces of healthy subjects to improve our understanding of gut microbial diversity. A majority of the bacterial sequences corresponded to
Paul B. Eckburg; Elisabeth M. Bik; Charles N. Bernstein; Elizabeth Purdom; Les Dethlefsen; Michael Sargent; Steven R. Gill; Karen E. Nelson; David A. Relman
Summary\\u000a Conclusion \\u000a A delay in intestinal transit time appears as an early event in acute pancreatitis, preceding intestinal bacterial overgrowth\\u000a and translocation.\\u000a \\u000a \\u000a \\u000a Background Septic complications, primarily caused by bacteria of enteric origin, are frequent in severe acute pancreatitis. Impairment\\u000a in intestinal motility probably plays a pathophysiological role in the development of bacterial overgrowth and ensuing translocation.\\u000a \\u000a \\u000a \\u000a Methods In the present study, the
Per Leveau; Xiangdong Wang; Vasile Soltesz; Ingemar Ihse; Roland Andersson
Development of an online-SPE-LC-MS method for the investigation of the intestinal absorption of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PHIP) and its bacterial metabolite PHIP-M1 in a Caco-2 Transwell system.
Heterocyclic aromatic amines such as PHIP are formed during the heat processing of food. PHIP undergoes bacterial metabolism leading to 7-hydroxy-5-methyl-3-phenyl-6,7,8,9-tetrahydropyrido[3',2':4,5]imidazo[1,2-a]pyrimidin-5-ium chloride (PHIP-M1) as main metabolite. We developed an LC-MS method with automated sample preparation by online-solid-phase-extraction for the simultaneous quantification of PHIP and its mammalian and bacterial metabolites N-hydroxy-PHIP, 4-OH-PHIP and PHIP-M1 in biological samples. The method was used to investigate the transport of PHIP-M1 through a Caco-2 cell monolayer. The experiments show that PHIP-M1 rapidly crosses the cell monolayer and that PHIP-M1 is a substrate for P-glycoprotein and the multiple drug resistance 2 transporter. The intestinal absorption of PHIP-M1 is comparable with that of PHIP and a moderate to high bioavailability has to be expected. Thus, not only the human metabolites of PHIP but also the bacterial metabolite PHIP-M1 formed in the gut could contribute to the toxic effects of PhIP. PMID:25053091
Willenberg, Ina; von Elsner, Leonie; Steinberg, Pablo; Schebb, Nils Helge
Excessive alcohol consumption poses a wide variety of significant immediate and long-term health risks. Ethanol biomarkers have clinical utility for detection, diagnosis, and treatment of alcohol use disorders as well as for screening for fetal alcohol exposure. Indirect biomarkers are those that reflect the toxic effects of ethanol on organs, tissues, or body biochemistry, whereas direct biomarkers are products of ethanol metabolism. Liver enzymes, carbohydrate deficient transferrin and mean corpuscular volume are discussed as examples of indirect markers of alcohol use. Commentary on the direct ethanol markers includes the following: acetaldehyde adducts, ethyl glucuronide, ethyl sulfate, phosphatidylethanol and fatty acids ethyl esters. PMID:22939298
Ingall, Glynnis B
The aim of this study was to evaluate different molecular tools based on the 16S rRNA gene, internal transcribed spacer, and the rpoB gene to examine the bacterial populations present in juvenile rainbow trout intestines. DNA was extracted from both pooled intestinal samples and bacterial strains. Genes were PCR-amplified and analysed using both temporal temperature gradient gel electrophoresis (TTGE) and restriction fragment length polymorphism methods. Because of the high cultivability of the samples, representative bacterial strains were retrieved and we compared the profiles obtained from isolated bacteria with the profile of total bacteria from intestinal contents. Direct analysis based on rpoB-TTGE revealed a simple bacterial composition with two to four bands per sample, while the 16S rRNA gene-TTGE showed multiple bands and comigration for a few species. Sequencing of the 16S rRNA gene- and rpoB-TTGE bands revealed that the intestinal microbiota was dominated by Lactococcus lactis, Citrobacter gillenii, Kluyvera intermedia, Obesumbacterium proteus, and Shewanella marinus. In contrast to 16S rRNA gene-TTGE, rpoB-TTGE profiles derived from bacterial strains produced one band per species. Because the single-copy state of rpoB leads to a single band in TTGE, the rpoB gene is a promising molecular marker for investigating the bacterial community of the rainbow trout intestinal microbiota. PMID:19780831
Navarrete, Paola; Magne, Fabien; Mardones, Pamela; Riveros, Macarena; Opazo, Rafael; Suau, Antonia; Pochart, Philippe; Romero, Jaime
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.
Alcohol is a drug with potentially devastating effects on the human body. While no less dangerous than many illegal drugs, society has accepted alcohol's negative consequences. Growing evidence, however, indicates that alcohol abuse and alcoholism jeopard...
A. J. Eidson
The observation that only a minority of heavy drinkers develop pancreatitis has prompted an intensive search for a trigger factor/cofactor/susceptibility factor that may precipitate a clinical attack. Putative susceptibility factors examined so far include diet, smoking, amount and type of alcohol consumed, the pattern of drinking and lipid intolerance. In addition, a range of inherited factors have been assessed including blood group antigens, human leukocyte antigen serotypes, alpha-1-antitrypsin phenotypes and several genotypes. The latter group comprises mutations/polymorphisms in genes related to alcohol-metabolizing enzymes, detoxifying enzymes, pancreatic digestive enzymes, pancreatic enzyme inhibitors, cystic fibrosis and cytokines. Disappointingly, despite this concerted research effort, no clear association has been established between the above factors and alcoholic pancreatitis. Experimentally, the secretagogue cholecystokinin (CCK) has been investigated as a candidate 'trigger' for alcoholic pancreatitis. However, the clinical relevance of CCK as a trigger factor has to be questioned, as it is difficult to envisage a situation in humans where abnormally high levels of CCK would be released into the circulation to trigger pancreatitis in alcoholics. In contrast, bacterial endotoxemia is a candidate cofactor that does have relevance to the clinical situation. Plasma lipopolysaccharide (LPS, an endotoxin) levels are significantly higher in drinkers (either after chronic alcohol intake or a single binge) compared to non-drinkers. We have recently shown that alcohol-fed animals challenged with otherwise innocuous doses of LPS exhibit significant pancreatic injury. Moreover, repeated LPS exposure in alcohol-fed rats leads to progressive injury to the gland characterized by significant pancreatic fibrosis. These studies support the concept that endotoxin may be an important factor in the initiation and progression of alcoholic pancreatitis. Scope remains for further studies examining proteins related to cellular anti-oxidant defenses, minor cystic fibrosis (CF) mutations and trans-heterozygosity involving a combination of mutations of different genes (such as CFTR alterations combined with SPINK1 or PRSS1 variants), as potential triggers of alcoholic pancreatitis. PMID:18336667
Apte, Minoti V; Pirola, Romano C; Wilson, Jeremy S
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
It is reported that Savannah Foods and Industries, in a joint venture with United States Sugar Corporation have applied for a loan guarantee for the production of alcohol from agricultural commodities. The two phase program calls for research and development, before a prototype plant will be built for the conversion of cellulosic compounds found in bagasse into alcohol for use as a fuel.
Data shows that elevated sialidase in bacterial vaginosis patients correlates to premature births in women. Bacterial sialidase also plays a significant role in the unusual colonization of Pseudomonas aeruginosa in cystic fibrosis patients. Crystals of Salmonella sialidase have been reproduced and are used for studying the inhibitor-enzyme complexes. These inhibitors may also be used to inhibit a trans-sialidase of Trypanosome cruzi, a very similar enzyme to bacterial sialidase, therefore preventing T. cruzi infection, the causitive agent of Chagas' disease. The Center for Macromolecular Crystallography suggests that inhibitors of bacterial sialidases can be used as prophylactic drugs to prevent bacterial infections in these critical cases.
The intestinal absorption of benzyl ?-glucoside (BNZ?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?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
Takashi Mizuma; Maya Nakamura; Hiroji Ina; Toshio Miyazaki; Masahiro Hayashi
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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
Gut microbial status induced by antibiotic growth promoter alters the prebiotic effects of dietary DVAQUA ® on Aeromonas hydrophila-infected tilapia: Production, intestinal bacterial community and non-specific immunity
The purpose of the present study was to investigate whether dietary antibiotic-induced changes in the fish intestinal microbiota altered host physiological responses to the infection with Aeromonas hydrophila in hybrid tilapia (Oreochromis niloticus ?×O. aureus ?). After an 8-week induction period with an antibiotic-supplemented or antibiotic-non-supplemented diet, 160 hybrid tilapias in 16 tanks were each injected with phosphate buffered saline
Zhigang Zhou; Suxu He; Yuchun Liu; Yanan Cao; Kun Meng; Bin Yao; Einar Ringø; Ilkyu Yoon
A common problem in patients with chronic liver diseases and liver cirrhosis is the development of ascites. First line therapy for ascites is the restriction of sodium intake and a diuretic treatment. Paracentesis is indicated in patients with large compromising volumes of ascites. In selected cases, permanent drainage of ascites over prolonged periods of time may be indicated. In the case presented here, a 66-year-old male patient, who was hospitalized with liver cirrhosis caused by alcoholic abuse, required permanent drainage of ascites. After three weeks of continuous ascites drainage, he developed bacterial peritonitis. Conventional attempts to remove the catheter by transcutaneous pulling failed and we thus decided to perform a median laparotomy to remove the catheter surgically. Intraoperatively an adhesion of the ascites drain (a so called ‘basket catheter’) to the mesentery very close to the small intestine was found, approximately 50 mm distal of the ligament suspensorium duodeni (ligament of Treitz). The basket catheter used for this patient was especially designed to drain infections, not fluids. We solved the adhesion, removed the basket catheter, placed a new surgical drain and finished the operation. The patient developed a rupture of his abdominal fascia suture 12 days later, which was caused by massive ascites and complicated by hepatorenal syndrome type I. The patient was taken to the operating theater again. After the second operation, the chronic liver failure decompensated and the patient died. Ascites caused by liver cirrhosis is still a medical challenge. The indication for the use of the correct percutaneous catheter for permanent paracentesis should be carefully considered. Some catheters are obviously not suited to drain ascites and may lead to fatal outcomes.
Kettler, B.; Schrem, H.; Klempnauer, J.; Grannas, G.
Background: Platelet-activating factor (PAF) may play a pivotal role in the pathogenesis of intestinal ischemic injury. Methods: The potential role of PAF in intestinal ischemia and reperfusion (I\\/R) and the development of gut endothelial and epithelial barrier dysfunction and distant organ injury were investigated by pretreatment with a PAF antagonist, lexipafant. Bidirectional permeability of the intestinal barrier, enteric bacterial translocation,
Zhengwu Sun; Xiangdong Wang; Xiaoming Deng; Åke Lasson; Vasile Soltesz; Anna Börjesson; Roland Andersson
We reviewed 38 controlled studies of marital and family therapy (MFT) in alcoholism treatment. We conclude that, when the alcoholic is unwilling to seek help, MFT is effective in helping the family cope better and motivating alcoholics to enter treatment. Specifically, (a) Al-Anon facilitation and referral help family members cope better; (b) Community Reinforcement and Family Training promotes treatment entry; and (c) the popular Johnson intervention apparently does not effectively promote treatment entry. Once the alcoholic enters treatment. MFT, particularly behavioral couples therapy (BCT), is clearly more effective than individual treatment at increasing abstinence and improving relationship functioning. BCT also reduces social costs, domestic violence, and emotional problems of the couple's children. Future studies need to specifically evaluate: MFT with women and with minority patients, mechanisms and processes of change, and transportability of evidence-based MFT approaches to clinical practice settings. PMID:12616803
O'Farrell, Timothy J; Fals-Stewart, William
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
BACKGROUND—There is controversy about whether the inflammatory response observed in the cystic fibrosis (CF) lung occurs secondary to bacterial infection or is caused by a dysregulation of the inflammatory response associated with the basic cellular defect of CF.?AIMS—To study the inflammatory response in the gastrointestinal tract of children with CF; and to investigate whether there is increased inflammation in the gastrointestinal tract of CF children with fibrosing colonopathy.?METHODS—Whole gut lavage was performed on 21 pancreatic insufficient children with CF, who were clinically well, five children with CF and fibrosing colonopathy, and 12 controls. Intestinal outputs of plasma derived proteins (albumin, ?1 antitrypsin, IgG), secretory immunoglobulins (IgA and IgM), cellular constituents (eosinophil cationic protein and neutrophil elastase), and cytokines (interleukin 8 and interleukin 1?) were measured.?RESULTS—Compared to controls, the 21 CF patients, with no intestinal complications, had increased intestinal outputs of albumin, IgG, IgM, eosinophil cationic protein, neutrophil elastase, interleukin 1?, and interleukin 8. Similar values were obtained for the CF patients with fibrosing colonopathy.?CONCLUSIONS—These data suggest that there is immune activation in the gastrointestinal mucosa of children with cystic fibrosis, which may result from the basic cellular defect. Fibrosing colonopathy does not appear to be associated with increased inflammation.??
Smyth, R.; Croft, N.; O'Hea, U.; Marshall, T.; Ferguson, A.
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
... join a treatment or sobriety program, such as Alcoholics Anonymous (see contact information under "Other Organizations"). These programs can provide the support you need to avoid relapse. Written by familydoctor.org editorial staff. American Academy ...
The metabolism of fructose by the small intestine can be analyzed in terms of the following scheme: (1) hydrolysis of fructose containing saccharides especially sucrose; (2) movement of fructose into the intestinal cell; (3) transformation of fructose int...
F. B. Stifel H. L. Greene R. H. Herman Y. F. Herman
Butyrate (BT) is one of the main end products of anaerobic bacterial fermentation of dietary fiber within the human colon.\\u000a Among its recognized effects, BT inhibits colon carcinogenesis. Our aim was to characterize uptake of BT by two nontransformed\\u000a intestinal epithelial cell lines: rat small intestinal epithelial (IEC-6) and fetal human colonic epithelial (FHC) cells.\\u000a Uptake of 14C-BT by IEC-6
Pedro GoncalvesJoao; João R. Araújo; Fátima Martel
The lower gastrointestinal tract is densely populated with resident microbial communities (microbiota), which do not elicit overt host responses but rather provide benefit to the host, including niche protection from pathogens. However, introduction of bacteria into the underlying tissue evokes acute inflammation. Non-typhoidal Salmonella serotypes (NTS) elicit this stereotypic host response by actively penetrating the intestinal epithelium and surviving in tissue macrophages. Initial responses generated by bacterial host cell interaction are amplified in tissue through the interleukin (IL)-18/interferon (IFN)-? and the IL-23/IL-17 axes, resulting in the activation of mucosal barrier functions against NTS dissemination. However, the pathogen is adapted to survive antimicrobial defenses encountered in the lumen of the inflamed intestine. This strategy enables NTS to exploit inflammation to outcompete the intestinal microbiota, and promotes their transmission by the fecal/oral route.
Santos, Renato L.; Raffatellu, Manuela; Bevins, Charles L.; Adams, L. Garry; Tukel, Cagla; Tsolis, Renee M.; Baumler, Andreas J.
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.
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
Summary Enteric hyperoxaluria and oxalate urolithiasis in patients with ileal resection seem to be caused by intestinal hyperabsorption of oxalate. The mechanism responsible for hyperabsorption of oxalate is not known. Intestinal transport of oxalic acid was therefore examined by an in vitro technique in rat intestine. Oxalic acid was absorbed by a mechanism of simple passive diffusion. The rate of
W. F. Caspary
Bacterial infections are frequent complications among patients treated for cancer. The type, severity, and treatment of bacterial infections vary and depend upon the specific malignancy, associated chemotherapies, and transplantation. This chapter discusses commonly encountered bacterial pathogens as well as Nocardia and mycobacteria in patients with cancer and addresses the clinical syndromes and management. Drug-resistant bacteria are becoming an increasingly recognized problem in patients with cancer. Antimicrobial resistance in select gram-positive and gram-negative bacteria are discussed along with the mechanisms of resistance and recommended therapies. PMID:24706222
Wilson, John W
Research on intestinal bacteria began around the end of the 19th century. During the last 5 decades of the 20th century, research on the intestinal microbiota made rapid progress. At first, in my work, I first developed a method of comprehensive analysis of the intestinal microbiota, and then I established classification and identification methods for intestinal anaerobes. Using these methods I discovered a number of ecological rules governing the intestinal microbiota and the role of the intestinl microbiota in health and disease. Moreover, using germfree animals, it was proven that the intestinal microbiota has a role in carcinogenesis and aging in the host. Thus, a new interdisciplinary field, “intestinal bacteriology” was established.
The aim of this overview article is to present the current possibilities of radionuclide scintigraphic small intestine imaging. Nuclear medicine has a few methods—scintigraphy with red blood cells labelled by means of 99mTc for detection of the source of bleeding in the small intestine, Meckel's diverticulum scintigraphy for detection of the ectopic gastric mucosa, radionuclide somatostatin receptor imaging for carcinoid, and radionuclide inflammation imaging. Video capsule or deep enteroscopy is the method of choice for detection of most lesions in the small intestine. Small intestine scintigraphies are only a complementary imaging method and can be successful, for example, for the detection of the bleeding site in the small intestine, ectopic gastric mucosa, carcinoid and its metastasis, or inflammation. Radionuclide scintigraphic small intestine imaging is an effective imaging modality in the localisation of small intestine lesions for patients in whom other diagnostic tests have failed to locate any lesions or are not available.
Dolezal, Jiri; Kopacova, Marcela
The intestinal immune system maintains a delicate balance between immunogenicity against invading pathogens and tolerance of the commensal microbiota and food antigens. Dendritic cells (DC) generate primary T-cell responses, and determine whether these responses are immunogenic or tolerogenic. The regulatory role of DC is of particular importance in the gut due to the high antigenic load. Intestinal DC act as sentinels, sampling potentially pathogenic antigens but also harmless antigens including the commensal microbiota. Following antigen acquisition, intestinal DC migrate to secondary lymphoid organs to activate naive T-cells. DC also imprint specific homing properties on T-cells that they stimulate; gut DC specifically induce gut-homing properties on T-cells upon activation, enabling T-cell migration back to intestinal sites. Data regarding properties on gut DC in humans is scarce, although evidence now supports the role of DC as important players in intestinal immunity in humans. Here, we review the role of intestinal DC in shaping mucosal immune responses and directing tissue-specific T-cell responses, with a special focus on the importance of distinguishing DC subsets from macrophages at intestinal sites. We compare and contrast human DC with their murine counterparts, and discuss the ability of the gut microbiota to shape intestinal DC function, and how this may be dysregulated in inflammatory bowel disease (IBD). Lastly, we describe recent advances in the study of probiotics on intestinal DC function, including the use of soluble secreted bacterial products. PMID:23352670
Mann, Elizabeth R; Landy, Jonathan D; Bernardo, David; Peake, Simon T C; Hart, Ailsa L; Al-Hassi, Hafid Omar; Knight, Stella C
We have recently described an association between irritable bowel syndrome (IBS) and abnormal lactulose breath test, suggesting small intestinal bacterial overgrowth (SIBO). However, the mechanism by which SIBO develops in IBS is unknown. In this case–control study we evaluate the role of small intestinal motility in subjects with IBS and SIBO. Small intestinal motility was studied in consecutive IBS subjects
Mark Pimentel; Edy E. Soffer; Evelyn J. Chow; Yuthana Kong; Henry C. Lin
Even though the number of alcohol-dependent women is only about 1/3 of the number of alcoholic men, the alcoholism in women, by its clinical features and its course, is the source of therapeutic and economic stakes, particularly in young women among whom an increase of alcohol consumption related problems is reported. Another specificity of the female alcoholism is the lack of care seeking, whereas women have tendency globally to solicit more often care structures than men. Women represent only 1/4 of the overall treated alcoholic patients. The main explanation for this phenomenon is the pejorative social and moral connotation of the female alcoholism, with frequent feelings of shame and deep guilt, that also account for the frequency of hidden and lonely alcohol intakes. The female alcoholism is essentially characterized by an increased vulnerability to the toxic effects of the alcohol, whereas the pathological consumption starts later and with smaller daily amounts. Most studies have revealed a higher vulnerability in women to somatic complications directly attributable to the alcohol organs toxicity, such as hepatic cirrhosis and cardiovascular complications (high blood pressure, non obstructive cardiomyopathy). The reported brain morphological abnormalities could also occur more precociously in alcoholic women than in men. A decreased corpus callosum size among alcoholic women, but not in alcoholic men, was thus found in a recent study, compared with healthy controls. Among the different hypothesis proposed to explain this increased alcohol toxicity, the most incriminated is higher alcohol blood rates for the same ingested amount, mainly of the fact of a lower size with a weaker proportion of the bodily total water, but also of weaker concentrations of gastro-intestinal tract ADH, or of a longer metabolism during some menstrual phases. Indeed, some experimental studies on animal showed that the alcohol toxic effects may occur only from a threshold of alcohol blood rate. More recent studies suggest that the explanation to keep is more related to the lower gastric metabolism in women (lower ADH activity), than the difference of gastric volume or alcohol hepatic oxidation. Regarding to comorbidity, in the Epidemiologic Catchment Area survey, 65% of women, versus 44% of men, with abuse and/or dependence to alcohol had at least one another life-time psychiatric disorder (mainly depression and anxiety disorders), compared to 36% of the overall women of the studied sample. On the other hand, the alcohol dependence is, more often than in men, secondary to other psychiatric disorders, essentially depressive episodes, but less associated to antisocial behaviours. Among the different etiopathogenic factors involved in the alcohol dependence occurrence, genetic factors seem to have a determinant impact. According to the previous family, separation/adoption and twins studies performed, genetic factors could explain 50 to 60% of the alcoholism vulnerability in both men and women. In this context, and whereas we assist to the development of etiopathogenic models with new therapeutic perspectives in alcohol dependence, it seems necessary not to neglect female alcoholism specificities. PMID:12506262
Since bacterial nitroreduction may play a critical role in the activation of nitropolycyclic aromatic hydrocarbons, we have used batch and semicontinuous culture systems to determine the ability of intestinal microflora to metabolize the carcinogen 6-nitrochrysene (6-NC). 6-NC was metabolized by the intestinal microflora present in the semicontinuous culture system to 6-aminochrysene (6-AC), N-formyl-6-aminochrysene (6-FAC), and 6-nitrosochrysene (6-NOC). These metabolites were isolated and identified by high-performance liquid chromatography, mass spectrometry, and UV-visible spectrophotometry and compared with authentic compounds. Almost all of the 6-NC was metabolized after 10 days. Nitroreduction of 6-NC to 6-AC was rapid; the 6-AC concentration reached a maximum at 48 h. The ratio of the formation of 6-AC to 6-FAC to 6-NOC at 48 h was 93.4:6.3:0.3. Interestingly, compared with results in the semicontinuous culture system, the only metabolite detected in the batch studies was 6-AC. The rate of nitroreduction differed among human, rat, and mouse intestinal microflora, with human intestinal microflora metabolizing 6-NC to the greatest extent. Since 6-AC has been shown to be carcinogenic in mice and since nitroso derivatives of other nitropolycyclic aromatic hydrocarbons are biologically active, our results suggest that the intestinal microflora has the enzymatic capacity to generate genotoxic compounds and may play an important role in the carcinogenicity of 6-NC.
Manning, B W; Campbell, W L; Franklin, W; Delclos, K B; Cerniglia, C E
The bacteria associated with the intestine and casts of the earthworm Lumbricus rubellus Hoffmeister, 1843, were examined by direct counts, culturability studies, 16S rRNA gene clone libraries, and fluorescent in situ hybridization (FISH). A significant fraction, 24–47%, of the total numbers of prokaryotes remaining in the intestine after casting were tightly associated with the intestinal wall. Bacterial 16S rRNA gene
David R. Singleton; Paul F. Hendrix; David C. Coleman; William B. Whitman
Sphingosine is known as a natural antimicrobial agent, protecting the human skin from bacterial colonization and possibly affecting the intestinal microbial community after ingestion. In this study we further investigated the antibacterial spectrum of dietary d-eythro-sphingosine in saline towards three intestinal pathogens and to the health promoting lactobacilli and bifidobacteria. The degree of bactericidal effect was studied using plate counts
Sam Possemiers; John Van Camp; Selin Bolca; Willy Verstraete
Objective In order to use facultative gut bacteria as an alternate to animals for the initial gastrointestinal toxicity screening of heavy metals, a comparative study on rat intestinal epithelial cells and resident gut bacteria was undertaken. Methods in vitro growth rate of four gut bacteria, dehydrogenase (DHA) and esterase (EA) activity test, intestinal epithelial and bacterial cell membrane enzymes and
RAJ K. UPRETI; A. KANNAN; RICHA SHRIVASTAVA; U. C. CHATURVEDI
It is thought that the normal enteric microflora acts not only to prevent intestinal colonization but also to prevent subsequent systemic dissemination of ingested, potentially pathogenic bacteria. To determine the relative roles of specific components of the intestinal bacterial flora in bacterial translocation out of the gut, mice were given various antimicrobial agents to selectively eliminate specific groups of intestinal bacteria. The cecal flora and the translocating bacteria in mesenteric lymph nodes were monitored both before and after oral inoculation with antibiotic-resistant Escherichia coli C25. Orally administered streptomycin selectively eliminated cecal facultative gram-negative bacilli, orally administered bacitracin-streptomycin eliminated all cecal bacterial species except low numbers of aerobic sporeformers, and parenterally administered metronidazole selectively eliminated cecal anaerobic bacteria. Compared with control mice, only metronidazole-treated mice had significantly increased rates of dissemination of intestinal bacteria into mesenteric lymph nodes, indicating that the exclusive absence of anaerobic bacteria facilitated the translocation of the intestinal facultative bacteria. In a parallel experiment with streptomycin-resistant E. coli C25 as a marker, parallel results were obtained. Metronidazole increased the translocation of the marker strain and the indigenous strains of intestinal bacteria. Thus, anaerobes appeared to play a key role in confining indigenous bacteria to the gut. However, intestinal colonization and translocation of E. coli C25 occurred most readily after bacitracin-streptomycin treatment, suggesting that in addition to anaerobic bacteria, other bacterial groups may play a role in limiting the intestinal colonization and extraintestinal dissemination of E. coli C25.
Wells, C L; Maddaus, M A; Reynolds, C M; Jechorek, R P; Simmons, R L
Circulating levels of endotoxin, interleukin (IL)-6, and tumor necrosis factor (TNF)-? increase with intestinal bacterial overgrowth and translocation, and are believed to be involved in the pathogenesis of hyperdynamic circulatory syndrome and functional renal failure in patients with advanced cirrhosis. We investigated the effects of the antibiotic rifaximin on systemic hemodynamics and renal function in patients with alcohol-related cirrhosis and ascites. We measured mean arterial pressure, cardiac output (CO) by Doppler ultrasound, systemic vascular resistance (as the ratio of mean arterial pressure:CO), plasma renin activity, levels of plasma aldosterone, the glomerular filtration rate by plasma clearance of technetium-99m-DTPA, natriuresis, levels of plasma endotoxin, and serum levels of IL-6 and TNF-? in 13 patients at baseline and after 4 weeks of treatment with rifaximin. Rifaximin treatment significantly reduced CO and significantly increased systemic vascular resistance, in association with a significant decrease in plasma rennin activity. The therapy also significantly increased the glomerular filtration rate and natriuresis while reducing levels of endotoxin, IL-6, and TNF-?. Intestinal decontamination with rifaximin improved systemic hemodynamics and renal function in patients with advanced cirrhosis. PMID:22391344
Kalambokis, Georgios N; Mouzaki, Athanasia; Rodi, Maria; Pappas, Konstantinos; Fotopoulos, Andreas; Xourgia, Xanthi; Tsianos, Epameinondas V
The investigation of the regularities of translocation of opportunistic pathogenic microflora from the small intestine lumen and abdominal cavity in diffuse peritonitis using labeled radionuclide colibacillus has shown that in normal condition the intestinal barrier is not permeable for bacteria. Under conditions of diffuse peritonitis the bacterial translocation and peritoneal resorption are developing since the first minutes of the disease. During the development of the pathological process the priority of the foci of bacterial toxemia is changed from peritoneal to intestinal. Relaparotomy with manipulations on the intestine in peritonitis induces sharp activation of bacteria translocation into the portal blood flow and systemic circulation. PMID:20387603
Grigor'ev, E G; Galeev, Iu M; Popov, M V
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
Cognitive impairment is frequently observed in patients with alcohol misuse or alcohol addiction. Multiple cognitive functions are reduced in these patients. Frontal lobe functions, as planning, abstract thinking, set shifting or continuous performance are most frequently affected. Alcohol amnestic syndrome, alcohol dementia and the Wernicke-Korsakow-Syndrome constitute distinct entities. Alcohol dementia follows the diagnostic criteria of dementia with clear evidence for alcohol abuse or alcohol addiction. The diagnostic procedure of alcohol-induced cognitive impairment includes medical history, physical and neuropsychiatric examinations; laboratory examinations, neuropsychological assessment, brain imaging and electroencephalographic recordings. At the moment, there are no established treatment options for alcohol-induced cognitive impairment. Some evidence is provided that nootropics might be of benefit. Alcohol abstinence is a most important step. Psychosocial interventions are essential to support the patients in their daily activities. PMID:11925780
Marksteiner, J; Bodner, T; Gurka, P
Initiation and perpetuation of the inflammatory intestinal responses in inflammatory bowel disease (IBD) may result from an exaggerated host defense reaction of the intestinal epithelium to endogenous lumenal bacterial flora. Intestinal epithelial cell lines constitutively express several functional Toll-like receptors (TLRs) which appear to be key regulators of the innate response system. The aim of this study was to characterize
ELKE CARIO; DANIEL K. PODOLSKY
In the 21st century, alcoholism and the consequences of ethyl alcohol abuse are major public health concerns in the United States, affecting approximately 14 million people. Pertinent to the global impact of alcoholism is the World Health Organisation estimate that 140 million people worldwide suffer from alcohol dependence. Alcoholism and alcohol abuse are the third leading causes of preventable death in the United States. Alcohol dependence and alcohol abuse cost the United State an estimated US$220 billion in 2005, eclipsing the expense associated with cancer (US$196 billion) or obesity (US$133 billion). Orally ingested ethyl alcohol is absorbed rapidly without chemical change from the stomach and intestine, reaching maximum blood concentration in about an hour. Alcohol crosses capillary membranes by simple diffusion, affecting almost every organ system in the body by impacting a wide range of cellular functions. Alcohol causes metabolic derangements either directly, via its chemical by-product or secondarily through alcohol-induced disorders. Many of these alcohol-related metabolic disturbances are increased in severity by the malnutrition that is common in those with chronic alcoholism. This review focuses on the acute and chronic injurious consequences of alcohol ingestion on the kidney, as well as the fluid, electrolyte and acid-base abnormalities associated with acute and chronic ingestion of alcohol.
Adewale, Adebayo; Ifudu, Onyekachi
Small intestine plays an important role in the sensing of various nutrients. There is information that would imply the existence of a dietary phosphate sensing mechanism within the intestine. Recent studies suggest that intestinal factors may involve in the alteration of renal phosphate transport. The elucidation of the phosphate sensing mechanism is expected to provide molecular basis for the prevention of the hyperphosphatemia in chronic kidney disease patients. PMID:23023634
Tatsumi, Sawako; Nomura, Kengo; Miyagawa, Atsumi; Kido, Shinsuke; Segawa, Hiroko
RECENTLY, J. J. Pindborg1 reported that bacterial synthesis of vitamin E takes place in the digestive tract of the rat; and he might have cited experiments by Daft et al.2 as presumptive confirmation. In both laboratories, rats which were subjected to sulpha drug-feeding to inhibit the activity of intestinal flora developed symptoms characteristic of vitamin E deficiency-muscle degeneration in Daft's
Philip L. Harris
Objectives We evaluated morphology and function of the gut in patients with chronic heart failure (CHF). Background Intestinal translocation of bacterial endotoxin may contribute to the inflammatory state observed in patients with CHF. The morphology and function of the gut may be abnormal. Methods We studied 22 patients with CHF (age 67 2 years, left ventricular ejection fraction (LVEF) 31
Anja Sandek; Juergen Bauditz; Alexander Swidsinski; Sabine Buhner; Jutta Weber-Eibel; Stephan von Haehling; Wieland Schroedl; Tim Karhausen; Wolfram Doehner; Mathias Rauchhaus; Philip Poole-Wilson; Hans-Dieter Volk; Herbert Lochs; Stefan D. Anker
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...
Antibiotic treatments have been used to modulate intestinal bacteria and investigate the role of intestinal bacteria on bile acid (BA) homeostasis. However, knowledge on which intestinal bacteria and bile acids are modified by antibiotics is limited. In the present study, mice were administered various antibiotics, 47 of the most abundant bacterial species in intestine, as well as individual BAs in plasma, liver, and intestine were quantified. Compared to the two antibiotic combinations (vancomycin+imipenem and cephalothin+neomycin), the three single antibiotics (metronidazole, ciprofloxacin and aztreonam) have less effect on intestinal bacterial profiles, and thus on host BA profiles and mRNA expression of genes that are important for BA homeostasis. The two antibiotic combinations decreased the ratio of Firmicutes to Bacteroidetes in intestine, as well as most secondary BAs in serum, liver and intestine. Additionally, the two antibiotic combinations significantly increased mRNA of the hepatic BA uptake transporters (Ntcp and Oatp1b2) and canalicular BA efflux transporters (Bsep and Mrp2), but decreased mRNA of the hepatic BA synthetic enzyme Cyp8b1, suggesting an elevated enterohepatic circulation of BAs. Interestingly, the two antibiotic combinations tended to have opposite effect on the mRNAs of most intestinal genes, which tended to be inhibited by vancomycin+imipenem but stimulated by cephalothin+neomycin. To conclude, the present study clearly shows that various antibiotics have distinct effects on modulating intestinal bacteria and host BA metabolism. PMID:24657338
Zhang, Youcai; Limaye, Pallavi B; Renaud, Helen J; Klaassen, Curtis D
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.
The mammalian intestine is home to a dense community of bacteria and its associated bacteriophage (phage). Virtually nothing is known about how phages impact the establishment and maintenance of resident bacterial communities in the intestine. Here, we examine the phages harbored by Enterococcus faecalis, a commensal of the human intestine. We show that E. faecalis strain V583 produces a composite phage (?V1/7) derived from two distinct chromosomally encoded prophage elements. One prophage, prophage 1 (?V1), encodes the structural genes necessary for phage particle production. Another prophage, prophage 7 (?V7), is required for phage infection of susceptible host bacteria. Production of ?V1/7 is controlled, in part, by nutrient availability, because ?V1/7 particle numbers are elevated by free amino acids in culture and during growth in the mouse intestine. ?V1/7 confers an advantage to E. faecalis V583 during competition with other E. faecalis strains in vitro and in vivo. Thus, we propose that E. faecalis V583 uses phage particles to establish and maintain dominance of its intestinal niche in the presence of closely related competing strains. Our findings indicate that bacteriophages can impact the dynamics of bacterial colonization in the mammalian intestinal ecosystem.
Duerkop, Breck A.; Clements, Charmaine V.; Rollins, Darcy; Rodrigues, Jorge L. M.; Hooper, Lora V.
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
Bacterial vaginosis is the commonest cause of abnormal vaginal discharge in women of childbearing age, with a prevalence as high as 50% in some communities. The symptoms of discharge and offensive smell can cause considerable distress, although 50% of women are asymptomatic when diagnosed. Microbiologically the usually dominant lactobacillus flora is overwhelmed by an overgrowth of predominantly anaerobic organisms, accompanied
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
Dietary impacts on health may be one of the oldest concepts in medicine; however, only in recent years have technical advances in mass spectroscopy, gnotobiology, and bacterial sequencing enabled our understanding of human physiology to progress to the point where we can begin to understand how individual dietary components can affect specific illnesses. This review explores the current understanding of the complex interplay between dietary factors and the host microbiome, concentrating on the downstream implications on host immune function and the pathogenesis of disease. We discuss the influence of the gut microbiome on body habitus and explore the primary and secondary effects of diet on enteric microbial community structure. We address the impact of consumption of non-digestible polysaccharides (prebiotics and fiber), choline, carnitine, iron, and fats on host health as mediated by the enteric microbiome. Disease processes emphasized include non-alcoholic fatty liver disease/non-alcoholic steatohepatitis, IBD, and cardiovascular disease/atherosclerosis. The concepts presented in this review have important clinical implications, although more work needs to be done to develop fully and validate potential therapeutic approaches. Specific dietary interventions offer exciting potential for nontoxic, physiologic ways to alter enteric microbial structure and metabolism to benefit the natural history of many intestinal and systemic disorders. PMID:24652102
Goldsmith, Jason R; Sartor, R Balfour
Bacterial infections traditionally have not been considered major causes of cancer. Recently, however, bacteria have been linked to cancer by two mechanisms: induction of chronic inflammation and production of carcinogenic bacterial metabolites. The most specific example of the inflammatory mechanism of carcinogenesis is Helicobacter pylori infection. H. pylori has been epidemiologically linked to adenocarcinoma of the distal stomach by its propensity to cause lifelong inflammation. This inflammation is in turn thought to cause cancer by inducing cell proliferation and production of mutagenic free radicals and N-nitroso compounds. H. pylori is the first bacterium to be termed a definite cause of cancer in humans by the International Agency for Research on Cancer. Mutagenic bacterial metabolites are also suspected to increase risk for cancer. This model is best exemplified in colon cancer. Bile salt metabolites increase colonic cell proliferation. Exogenous compounds such as rutin may be metabolized into mutagens by resident colonic flora. Moreover, Bacteroides species can produce fecapentaenes, potent in vitro mutagens, in relatively high concentrations. In vivo data on human carcinogenesis by bacterial metabolites, however, are inconsistent. Local bacterial infections may also predispose to nonnodal lymphomas, although the mechanisms for this are unknown. Gastric lymphomas and immunoproliferative small intestinal disease have been most strongly linked to underlying bacterial infection. Because bacterial infections can be cured with antibiotics, identification of bacterial causes of malignancy could have important implications for cancer prevention.
Being born to an alcoholic parent clearly raises the risk that a man will become an alcoholic, as shown by studies of adopted sons of alcoholic and nonalcoholic biologic parents. Being raised by an alcoholic parent, however, seems not to increase this risk. Alcoholics may possess some sort of biochemical tolerance for alcohol, perhaps based on more efficient detoxification mechanisms than those of moderate drinkers. PMID:669679
Goodwin, D W
Purpose of review Interactions of the gut microbiome with the host are important in health and disease. Microbial translocation releases bacterial products that play a key role in progression of chronic liver disease by promoting hepatic injury and inflammation. Although this has long been recognized, we are just beginning to understand the circumstances under which the gut becomes leaky and to discover bacterial metabolites that promote liver disease. In this review we will summarize recent findings from the last two years. Recent findings Chronic liver disease is associated with an altered microbiome with both qualitative (dysbiosis) and quantitative (overgrowth) differences. This can be viewed as a loss of the symbiotic relationship between the microflora and the host. An imbalanced intestinal homeostasis results in a breach of the gut barrier and subsequent microbial translocation. However, the contribution of the intestinal microflora is beyond simple microbial translocation as pathogenic factor. Bacterial metabolites resulting from an imbalanced homeostasis and dysbiosis play also a crucial role in liver disease. Summary A combination between an initiating liver insult and a disturbance of the gut – host symbiosis synergize in progression of liver disease.
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 significantly higher than that in control rats (20%, P<0.01). Plasma endotoxin level was significantly higher in experimental group than in control group. Permeability of the epithelial mucosa and pathological alteration were increased in the ileum and the microvilli became shorter and thinner in rats with portal hypertension. CONCLUSION: Bacterial translocation occurs in rats with CCl4-induced portal hypertension and increased permeability between epithelial cells contributes to the translocation.
Yao, Guo-Xiang; Shen, Zhong-Yi; Xue, Xin-Bo; Yang, Zhen
Bacterial microcompartments (BMCs) are organelles composed entirely of protein. They promote specific metabolic processes by encapsulating and colocalizing enzymes with their substrates and cofactors, by protecting vulnerable enzymes in a defined microenvironment, and by sequestering toxic or volatile intermediates. Prototypes of the BMCs are the carboxysomes of autotrophic bacteria. However, structures of similar polyhedral shape are being discovered in an ever-increasing number of heterotrophic bacteria, where they participate in the utilization of specialty carbon and energy sources. Comparative genomics reveals that the potential for this type of compartmentalization is widespread across bacterial phyla and suggests that genetic modules encoding BMCs are frequently laterally transferred among bacteria. The diverse functions of these BMCs suggest that they contribute to metabolic innovation in bacteria in a broad range of environments. PMID:20825353
Kerfeld, Cheryl A; Heinhorst, Sabine; Cannon, Gordon C
Infections with enteric pathogens like enterotoxigenic Escherichia coli (ETEC) is a major health issue worldwide and while diarrhea is the major problem, prolonged, severe, and dual infections with multiple pathogens may also compromise the nutritional status of the infected individuals. There is almost nothing currently known about the effect of ETEC infection on intestinal absorptions of water-soluble vitamins including thiamin. We examined the effect of ETEC infection on intestinal uptake of the thiamin using as a model the human-derived intestinal epithelial Caco-2 cells. The results showed that infecting confluent Caco-2 monolayers with live ETEC (but not with boiled/killed ETEC or nonpathogenic E. coli) or treatment with bacterial culture supernatant led to a significant inhibition in thiamin uptake. This inhibition appears to be caused by a heat-labile and -secreted ETEC component and is mediated via activation of the epithelial adenylate cyclase system. The inhibition in thiamin uptake by ETEC was associated with a significant reduction in expression of human thiamin transporter-1 and -2 (hTHTR1 and hTHTR2) at the protein and mRNA levels as well as in the activity of the SLC19A2 and SLC19A3 promoters. Dual infection of Caco-2 cells with ETEC and EPEC (enteropathogenic E. coli) led to compounded inhibition in intestinal thiamin uptake. These results show for the first time that infection of human intestinal epithelial cells with ETEC causes a significant inhibition in intestinal thiamin uptake. This inhibition is mediated by a secreted heat-labile toxin and is associated with a decrease in the expression of intestinal thiamin transporters. PMID:24133060
Ghosal, Abhisek; Chatterjee, Nabendu S; Chou, Tristan; Said, Hamid M
Cell shape is not the product of a particular gene or protein, but the result of the collective actions of many of them. These\\u000a are involved in several processes, including peptidoglycan precursor synthesis, peptidoglycan synthesis and recycling, cell\\u000a elongation, cell septation and division site selection. The analysis of the “morphogene” content of several bacterial genomes\\u000a suggests that there are three
Jesús Mingorance; Anabel Rico; Paulino GÓmez-Puertas
This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Hirokazu Yokoyama and David Crabb. The presentations were (1) Roles of vitamin A, retinoic acid, and retinoid receptors in the expression of liver ALDH2, by J. Pinaire, R. Hasanadka, M. Fang, and David W. Crabb; (2) Alcohol, vitamin A, and beta-carotene: Adverse interactions, by M. A. Leo and Charles S. Lieber; (3) Retinoic acid, hepatic stellate cells, and Kupffer cells, by Hidekazu Tsukamoto, K. Motomura, T. Miyahara, and M. Ohata; (4) Retinoid storage and metabolism in liver, by William Bosron, S. Sanghani, and N. Kedishvili; (5) Characterization of oxidation pathway from retinol to retinoic acid in esophageal mucosa, by Haruko Shiraishi, Hirokazu Yokoyama, Michiko Miyagi, and Hiromasa Ishii; and (6) Ethanol in an inhibitor of the cytosolic oxidation of retinol in the liver and the large intestine of rats as well as in the human colon mucosa, by Ina Bergheim, Ina Menzl, Alexandr Parlesak, and Christiane Bode. PMID:11391073
Crabb, D W; Pinairs, J; Hasanadka, R; Fang, M; Leo, M A; Lieber, C S; Tsukamoto, H; Motomura, K; Miyahara, T; Ohata, M; Bosron, W; Sanghani, S; Kedishvili, N; Shiraishi, H; Yokoyama, H; Miyagi, M; Ishii, H; Bergheim, I; Menzl, I; Parlesak, A; Bode, C
The metabolic effects of ethanol are due to a direct action of ethanol or its metabolites, changes in the redox state occurring during its metabolism, and modifications of the effects of ethanol by nutritional factors. Ethanol causes hyperglycemia or hypoglycemia depending on whether glycogen stores are adequate, inhibits protein synthesis, and results in fatty liver and in elevations in serum triglyceride levels. Increases in high-density lipoprotein cholesterol after ethanol ingestion may explain the lower risk of myocardial infarction and death from coronary disease after moderate drinking. Increases in serum lactate, resulting from the increased NADH/NAD+ ratio, and hyperuricemia, most likely the result of increased turnover of adenine nucleotides, are common transient effects of ethanol ingestion. Causes of vitamin deficiencies in alcoholism are decreased dietary intake, decreased intestinal absorption, and alterations in vitamin metabolism. Ethanol decreases thiamine absorption and decreases the enterohepatic circulation of folate. Acetaldehyde increases the degradation of pyridoxal 5'-phosphate by displacing it from its binding protein and making it susceptible to hydrolysis by membrane-bound alkaline phosphatase. Ethanol decreases hepatic vitamin A concentration and its conversion to active retinal, and modifies renal metabolism of vitamin D. PMID:3881285
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
Although the number of homosexual alcoholic men and women has been estimated to be proportionately three times greater than the number of alcoholics in the general population, their participation in Alcoholics Anonymous is not consistent with this proportional representation. It is proposed that there are a number of characteristics of AA, as it is represented in meetings, which discourage participation
William E. Bittle
Objective Acute alcohol intoxication increases intestinal lymph flow by unknown mechanisms, potentially impacting mucosal immunity. We tested the hypothesis that enhanced intrinsic pump function of mesenteric lymphatics contributes to increased intestinal lymph flow during alcohol intoxication. Methods Acute alcohol intoxication was produced by intragastric administration of 30% alcohol to concious, unrestrained rats through surgically-implanted catheters. Time-matched controls received either no bolus, vehicle, or isocaloric dextrose. Thirty minutes after alcohol administration, rats were anesthetized and mesenteric collecting lymphatics were isolated and cannulated to study intrinsic pumping parameters. In separate experiments, mesenteric lymphatics were isolated to examine direct effects of alcohol on intrinsic pump activity. Results Lymphatics isolated from alcohol-intoxicated animals displayed slgnificantly decreased contraction frequency (CF) than the dextrose group, elevated stroke volume index (SVI) versus all other groups, and decreased myogenic responsiveness compared to sham. Elevating pressure from 2 to 4 cm H2O increased the volume flow index 2.4-fold in the alcohol group versus 1.4-fold for shams. Isolated lymphatics exposed to 20 mM alcohol had reduced myogenic tone, without changes in CF or SVI. Conclusions Alcohol intoxication enhances intrinsic pumping by mesenteric collecting lymphatics. Alcohol directly decreases lymphatic myogenic tone, but effects on phasic contractions occur by an unidentified mechanism.
Souza-Smith, Flavia M.; Kurtz, Kristine M.; Molina, Patricia E.; Breslin, Jerome W.
Background and Aims Celiac 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, gliadin translocation, and cytokine production. Methodology/Principal Findings Changes in gut mucosa were assessed in the intestinal loops of inbred Wistar-AVN rats that were reared under germ-free conditions in the presence of various intestinal bacteria (enterobacteria and bifidobacteria isolated from CD patients and healthy children, respectively) and CD-triggering agents (gliadin and IFN-?) by histology, scanning electron microscopy, immunofluorescence, and a rat cytokine antibody array. Adhesion of the bacterial strains to the IEC-6 rat cell line was evaluated in vitro. Gliadin fragments alone or together with the proinflammatory cytokine interferon (IFN)-? significantly decreased the number of goblet cells in the small intestine; this effect was more pronounced in the presence of Escherichia coli CBL2 and Shigella CBD8. Shigella CBD8 and IFN-? induced the highest mucin secretion and greatest impairment in tight junctions and, consequently, translocation of gliadin fragments into the lamina propria. Shigella CBD8 and E. coli CBL2 strongly adhered to IEC-6 epithelial cells. The number of goblet cells in small intestine increased by the simultaneous incubation of Bifidobacterium bifidum IATA-ES2 with gliadin, IFN-? and enterobacteria. B. bifidum IATA-ES2 also enhanced the production of chemotactic factors and inhibitors of metalloproteinases, which can contribute to gut mucosal protection. Conclusions Our results suggest that the composition of the intestinal microbiota affects the permeability of the intestinal mucosa and, consequently, could be involved in the early stages of CD pathogenesis.
Cinova, Jana; De Palma, Giada; Stepankova, Renata; Kofronova, Olga; Kverka, Miloslav; Sanz, Yolanda; Tuckova, Ludmila
Roots and bark from plants belonging to genus Salacia of the family Hippocrateaceae (Salacia reticulata, Salacia oblonga, etc.) have been used for traditional Ayurvedic medicine, particularly for the treatment of diabetes. In our study, we evaluated the gene expression profiles in the small intestinal epithelium of rats that were given a Salacia plant extract to gain insight into its effects on the small intestine. In detail, DNA microarray analysis was performed to evaluate the gene expression profiles in the rat ileal epithelium. The intestinal bacterial flora was also studied using T-RFLP (Nagashima method) in these rats. Expressions of many immune-related genes, especially Th1-related genes associated with cell-mediated immunity, were found to increase in the small intestinal epithelium and the intestinal bacterial flora became similar to those in the case with Salacia plant extract administration. Our study thus revealed that Salacia plant extract exerts bioregulatory functions by boosting intestinal immunity. PMID:21328625
Oda, Yuriko; Ueda, Fumitaka; Kamei, Asuka; Kakinuma, Chihaya; Abe, Keiko
Regular consumption of moderate doses of wine is an integral part of the Mediterranean diet, which has long been considered to provide remarkable health benefits. Wine?s beneficial effect has been attributed principally to its non-alcoholic portion, which has antioxidant properties, and contains a wide variety of phenolics, generally called polyphenols. Wine phenolics may prevent or delay the progression of intestinal diseases characterized by oxidative stress and inflammation, especially because they reach higher concentrations in the gut than in other tissues. They act as both free radical scavengers and modulators of specific inflammation-related genes involved in cellular redox signaling. In addition, the importance of wine polyphenols has recently been stressed for their ability to act as prebiotics and antimicrobial agents. Wine components have been proposed as an alternative natural approach to prevent or treat inflammatory bowel diseases. The difficulty remains to distinguish whether these positive properties are due only to polyphenols in wine or also to the alcohol intake, since many studies have reported ethanol to possess various beneficial effects. Our knowledge of the use of wine components in managing human intestinal inflammatory diseases is still quite limited, and further clinical studies may afford more solid evidence of their beneficial effects.
Biasi, Fiorella; Deiana, Monica; Guina, Tina; Gamba, Paola; Leonarduzzi, Gabriella; Poli, Giuseppe
The gastrointestinal (GI) tract of invasive land snail Achatina fulica is known to harbor metabolically active bacterial communities. In this study, we assessed the bacterial diversity in the different regions of GI tract of Giant African snail, A. fulica by culture-independent and culture-dependent methods. Five 16S rRNA gene libraries from different regions of GI tract of active snails indicated that sequences affiliated to phylum ?-Proteobacteria dominated the esophagus, crop, intestine, and rectum libraries, whereas sequences affiliated to Tenericutes dominated the stomach library. On phylogenetic analysis, 30, 27, 9, 27, and 25 operational taxonomic units (OTUs) from esophagus, crop, stomach, intestine, and rectum libraries were identified, respectively. Estimations of the total bacterial diversity covered along with environmental cluster analysis showed highest bacterial diversity in the esophagus and lowest in the stomach. Thirty-three distinct bacterial isolates were obtained, which belonged to 12 genera of two major bacterial phyla namely ?-Proteobacteria and Firmicutes. Among these, Lactococcus lactis and Kurthia gibsonii were the dominant bacteria present in all GI tract regions. Quantitative real-time polymerase chain reaction (qPCR) analysis indicated significant differences in bacterial load in different GI tract regions of active and estivating snails. The difference in the bacterial load between the intestines of active and estivating snail was maximum. Principal component analysis (PCA) of terminal restriction fragment length polymorphism suggested that bacterial community structure changes only in intestine when snail enters estivation state. PMID:23233413
Pawar, Kiran D; Banskar, Sunil; Rane, Shailendra D; Charan, Shakti S; Kulkarni, Girish J; Sawant, Shailesh S; Ghate, Hemant V; Patole, Milind S; Shouche, Yogesh S
The gastrointestinal (GI) tract of invasive land snail Achatina fulica is known to harbor metabolically active bacterial communities. In this study, we assessed the bacterial diversity in the different regions of GI tract of Giant African snail, A. fulica by culture-independent and culture-dependent methods. Five 16S rRNA gene libraries from different regions of GI tract of active snails indicated that sequences affiliated to phylum ?-Proteobacteria dominated the esophagus, crop, intestine, and rectum libraries, whereas sequences affiliated to Tenericutes dominated the stomach library. On phylogenetic analysis, 30, 27, 9, 27, and 25 operational taxonomic units (OTUs) from esophagus, crop, stomach, intestine, and rectum libraries were identified, respectively. Estimations of the total bacterial diversity covered along with environmental cluster analysis showed highest bacterial diversity in the esophagus and lowest in the stomach. Thirty-three distinct bacterial isolates were obtained, which belonged to 12 genera of two major bacterial phyla namely ?-Proteobacteria and Firmicutes. Among these, Lactococcus lactis and Kurthia gibsonii were the dominant bacteria present in all GI tract regions. Quantitative real-time polymerase chain reaction (qPCR) analysis indicated significant differences in bacterial load in different GI tract regions of active and estivating snails. The difference in the bacterial load between the intestines of active and estivating snail was maximum. Principal component analysis (PCA) of terminal restriction fragment length polymorphism suggested that bacterial community structure changes only in intestine when snail enters estivation state.
Pawar, Kiran D; Banskar, Sunil; Rane, Shailendra D; Charan, Shakti S; Kulkarni, Girish J; Sawant, Shailesh S; Ghate, Hemant V; Patole, Milind S; Shouche, Yogesh S
Nurses' attitudes toward the alcoholic can have a profound impact on the person suffering from alcoholism. These attitudes can affect the alcoholic's care and even whether the alcoholic chooses to recover. This study investigated attitudes of approximately 68 nurses employed in hospitals, 49 nurses in treatment facilities, 58 nursing students, and…
Speer, Rita D.
This article reports the results of research designed to identify personality characteristics and psychopathology of adult children of alcoholics (ACOA profile), using the Clinical Analysis Questionnaire. Subjects were divided into four groups based on whether they were alcoholic adults who were not ACOAs (n = 73, alcoholic adults who were ACOAs (n = 91), adults who were not alcoholics but
Dennis R. Carpenter
Ethanol intoxication and ethanol use are associated with a variety of metabolic derangements encountered in the Emergency Department. In this article, the authors discuss alcohol intoxication and its treatment, dispel the myth that alcohol intoxication is associated with hypoglycemia, comment on electrolyte derangements and their management, review alcoholic ketoacidosis, and end with a section on alcoholic encephalopathy. PMID:24766933
Allison, Michael G; McCurdy, Michael T
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
Several arguments are in favour of the use of antidepressant drugs in alcohol-dependent patients, especially those acting on the serotoninergic system: (1) neurochemical data indicate the interaction between alcohol and 5-HT metabolism, (2) pharmacological studies show an improvement in the behaviour of alcoholized animals treated with antidepressants, (3) depression is a frequent disease in alcoholic patients. Tianeptine has been shown
J. D Favre; C Guelfi-Sozzi; B Delalleau; H Lôo
This article presents an examination and evaluation of the role of psychiatry in the treatment of alcoholism, and an interpretation of the nature of addiction and the concept of alcoholism as an addictive disease. It treats the conflicts and problems of the alcoholic with a description of common neurotic methods used to solve them; the psychological needs served by alcohol;
An in vitro intestinal tissue model was developed for the investigation of bacterial association in the pig small intestine under different dietary regimes. In preliminary experiments, jejunal and ileal tissue was taken from Danish Landrace pigs fed standard diet and inoculated with either Salmonella or nonpathogenic Esche- richia coli strains. Higher numbers of salmonellae associated with the ileal tissues, but
PATRICK J. NAUGHTON; LENE LIND MIKKELSEN; BENT BORG JENSEN
Intestinal transplantation has been gradually instituted in the management of intestinal failure. More than 200 cases including isolated intestinal transplant, liver/intestinal transplant, and multivisceral transplant have been performed worldwide,with 1-year graft and patient survival rates of 66% and 54%,respectively. Indications for the procedure include short bowel syndrome and functional abnormalities secondary to a variety of diseases or conditions. Tacrolimus-based immunosuppression regimens have been used universally with improved outcomes. The major contributors to the morbidity and mortality include rejection,infection, and technical complications. Of those, control of rejection remains the most difficult dilemma and it will be the key to improved patient and graft survival. PMID:11865353
Kato, Tomoaki; Ruiz, Phillip; Thompson, John F; Eskind, Lon B; Weppler, Deborah; Khan, Farrukh A; Pinna, Antonio D; Nery, Jose R; Tzakis, Andreas G
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Alcohol misuse in young people is of growing concern, even though alcohol consumption among adolescents has declined over recent years. Many 15 year olds have already consumed alcohol and adolsecents tend to consume large quantities of alcohol in one sitting. This article describes the problem of alcohol misuse in young people and the nurse's role in the prevention and treatment of alcohol misuse in this population. A stepped care, holistic approach is recommended, taking into consideration peer and family influence on alcohol misuse and the young person's motivation to change their behaviour. PMID:22908763
Davies, Nicola J
Alcohol is widely consumed across the world in different cultural and social settings. Types of alcohol consumption differ between (a) light, only occasional consumption, (b) heavy chronic alcohol consumption, and (c) binge drinking as seen as a new pattern of alcohol consumption among teenagers and young adults. Heavy alcohol consumption is detrimental to many organs and tissues, including bones. Osteoporosis is regularly mentioned as a secondary consequence of alcoholism, and chronic alcohol abuse is established as an independent risk factor for osteoporosis. The review will present the different mechanisms and effects of alcohol intake on bone mass, bone metabolism, and bone strength, including alcoholism-related "life-style factors" such as malnutrition, lack of exercise, and hormonal changes as additional causative factors, which also contribute to the development of osteoporosis due to alcohol abuse. PMID:24477631
Opinion statement Small bowel bacterial overgrowth (SBBO) syndrome is associated with excessive numbers of bacteria in the proximal small intestine.\\u000a The pathology of this condition involves competition between the bacteria and the human host for ingested nutrients. This\\u000a competition leads to intraluminal bacterial catabolism of nutrients, often with production of toxic metabolites and injury\\u000a to the enterocyte. A complex array of
Virmeet V. Singh; Phillip P. Toskes
Small bowel bacterial overgrowth (SBBO) syndrome is associated with excessive numbers of bacteria in the proximal small intestine.\\u000a The pathology of this condition involves competition between the bacteria and the human host for ingested nutrients. This\\u000a competition leads to intraluminal bacterial catabolism of nutrients, often with production of toxic metabolites and injury\\u000a to the enterocyte. A complex array of clinical
Virmeet V. Singh; Phillip P. Toskes
Spontaneous translocation of the normal intestinal flora was observed in higher rate in old mice being in a state of thymus involution than in young ones. The proportion of bacterial translocation 24 and 48 h after cold stress increased in both young and old mice, the increase of translocation as compared to controls was larger in case of young mice than in old ones. The distribution of isolated bacterial strains according to Gram stain also differed in young and old groups. PMID:2100901
Anderlik, P; Szeri, I; Bános, Z; Barna, Z
The inflammasomes have an important role in connecting the detection of endogenous and microbial danger signals to caspase-1 activation and induction of protective immune responses. NLRC4 is a cytosolic NOD (nucleotide binding and oligomerization domain)-like receptor (NLR) that can trigger inflammasome formation in response to bacterial flagellin, an immunodominant antigen in the intestine. To characterize the role of NLRC4 in bacterially triggered intestinal inflammation, we used the murine pathogen Citrobacter rodentium, an extracellular, attaching/effacing bacterium similar to enterohemorrhagic Escherichia coli and enteropathogenic E. coli. Following infection with C. rodentium, we found that Nlrc4(-/-) mice developed more severe weight loss, increased bacterial colonization levels, and exacerbated intestinal inflammation compared with wild-type counterparts. Nlrc4(-/-) mice mounted robust adaptive immune responses but were unable to control early colonization by C. rodentium, suggesting that a defect in innate immunity was responsible. Experiments using bone marrow (BM) chimeras revealed that the protective effects of NLRC4 were dependent on its expression in non-hematopoietic cells, and quantitative PCR (Q-PCR) analyses revealed that NLRC4 was highly expressed in epithelial crypts but not in intestinal stroma. Thus, early NLRC4 sensing in intestinal epithelial cells regulates colonization by an extracellular bacterial pathogen and limits subsequent intestinal damage. PMID:24280936
Nordlander, S; Pott, J; Maloy, K J
Background Antimicrobial growth promoters (AGPs) are antimicrobial agents administered to livestock in feed for prolonged periods to enhance feed efficiency. Beef cattle are primarily finished in confined feeding operations in Canada and the USA, and the administration of AGPs such as chlortetracycline and sulfamethazine (Aureo S-700 G) is the standard. The impacts of AGPs on the intestinal microbiota of beef cattle are currently uncertain; it is documented that AGPs administered to beef cattle pass through the rumen and enter the intestine. To ascertain the impacts of Aureo S-700 G on the small and large intestinal microbiota of beef cattle (mucosa-associated and within digesta), terminal restriction fragment length polymorphism (T-RFLP) analysis and quantitative PCR (qPCR) for total bacteria were applied. Beef cattle were maintained in an experimental feedlot (five replicate pens per treatment), and AGP treatment cattle were administered Aureo S-700 G in feed, whereas control cattle were administered no antimicrobials. As the intestinal microbiota of beef cattle has not been extensively examined, clone library analysis was applied to ascertain the primary bacterial constituents of the intestinal microbiota. Results Comparative T-RFLP and qPCR analysis (n?=?122 samples) revealed that bacterial community fingerprints and bacterial load within digesta differed from those associated with mucosa. However, the administration of Aureo S-700 G did not affect bacterial community fingerprints or bacterial load within the small and large intestine relative to control cattle. Analysis of >1500 near full length 16S rDNA clones revealed considerably greater bacterial diversity in the large relative to the small intestine of beef cattle. Mucosa-associated bacterial communities in the jejunum were dominated by Proteobacteria, and differed conspicuously from those in the ileum and large intestine. Although the ileum contained bacterial clones that were common to the jejunum as well as the cecum, Firmicutes clones associated with mucosa dominated in the ileum, cecum, and descending colon. In the descending colon, clone library analysis did not reveal a difference in the richness or diversity of bacterial communities within digesta relative to those associated with mucosa. However, T-RFLP analysis indicated a significant difference in T-RF relative abundance (i.e. difference in relative taxon abundance) between mucosa-associated and digesta communities attributed in part to the differential abundance of Bacteriodes, Alistipes, Oscillibacter, and unclassified Clostridiales. Conclusions These data demonstrate that there was no significant difference in the composition of the predominant intestinal bacteria constituents within animals administered Aureo S-700 G and those not administered AGPs after a 28 day withdrawal period.
Sensing their environment is a crucial ability of all life forms. In higher eukaryotes the sensing of airborne volatile compounds, or olfaction, is well developed. In plants, slime moulds and yeast there is also compelling evidence that these organisms can smell their environment and respond accordingly. Here we show that bacteria are also capable of olfaction. Bacillus licheniformis was able to sense airborne volatile metabolites produced by neighbouring bacterial cultures and cells could respond to this chemical information in a coordinated way. When Bacillus licheniformis was grown in a microtitre plate adjacent to a bacterial culture of the same or a different species, growing in complex medium, biofilm formation and pigment production were elicited by volatile molecules. A weaker response occurred in increasingly distant wells. The emitted volatile molecule was identified as ammonia. These data demonstrate that B. licheniformis has evolved the ability collect information about its environment from the surrounding air and physiologically respond to it in a manner similar to olfaction. This is the first time that a behavioural response triggered by odorant molecules received through the gas phase is described in bacteria. PMID:20721987
Nijland, Reindert; Burgess, J Grant
Intestines are organs that not only digest food and absorb nutrients, but also provide a defense barrier against pathogens and noxious agents ingested. Tight junctions (TJs) are the most apical component of the junctional complex, providing one form of cell-cell adhesion in enterocytes and playing a critical role in regulating paracellular barrier permeability. Alteration of TJs leads to a number of pathophysiological diseases causing malabsorption of nutrition and intestinal structure disruption, which may even contribute to systemic organ failure. Claudins are the major structural and functional components of TJs with at least 24 members in mammals. Claudins have distinct charge-selectivity, either by tightening the paracellular pathway or functioning as paracellular channels, regulating ions and small molecules passing through the paracellular pathway. In this review, we have discussed the functions of claudin family members, their distribution and localization in the intestinal tract of mammals, their alterations in intestine-related diseases and chemicals/agents that regulate the expression and localization of claudins as well as the intestinal permeability, which provide a therapeutic view for treating intestinal diseases.
Lu, Zhe; Ding, Lei; Lu, Qun; Chen, Yan-Hua
Mammals coexist with a luxuriant load of bacteria in the lower intestine (up to 10(12) organisms/g of intestinal contents). Although these bacteria do not cause disease if they remain within the intestinal lumen, they contain abundant immunostimulatory molecules that trigger immunopathology if the bacteria penetrate the body in large numbers. The physical barrier consists only of a single epithelial cell layer with overlying mucus, but comparisons between animals kept in germ-free conditions and those colonized with bacteria show that bacteria induce both mucosal B cells and some T cell subsets; these adaptations are assumed to function as an immune barrier against bacterial penetration, but the mechanisms are poorly understood. In mice with normal intestinal flora, but no pathogens, there is a secretory IgA response against bacterial membrane proteins and other cell wall components. Whereas induction of IgA against cholera toxin is highly T help dependent, secretory IgA against commensal bacteria is induced by both T independent and T dependent pathways. When animals are kept in clean conditions and free of pathogens, there is still a profound intestinal secretory IgA response against the commensal intestinal flora. However, T dependent serum IgG responses against commensal bacteria do not occur in immunocompetent animals unless they are deliberately injected intravenously with 10(4) to 10(6) organisms. In other words, unmanipulated pathogen-free mice are systemically ignorant but not tolerant of their commensal flora despite the mucosal immune response to these organisms. In mice that are challenged with intestinal doses of commensal bacteria, small numbers of commensals penetrate the epithelial cell layer and survive within dendritic cells (DC). These commensal-loaded DC induce IgA, but because they are confined within the mucosal immune system by the mesenteric lymph nodes, they do not induce systemic immune responses. In this way the mucosal immune responses to commensals are geographically and functionally separated from systemic immunity. PMID:15681741
Macpherson, Andrew J; Uhr, Therese
Intestinal lymphangiectasia in the adult may be characterized as a disorder with dilated intestinal lacteals causing loss of lymph into the lumen of the small intestine and resultant hypoproteinemia, hypogammaglobulinemia, hypoalbuminemia and reduced number of circulating lymphocytes or lymphopenia. Most often, intestinal lymphangiectasia has been recorded in children, often in neonates, usually with other congenital abnormalities but initial definition in adults including the elderly has become increasingly more common. Shared clinical features with the pediatric population such as bilateral lower limb edema, sometimes with lymphedema, pleural effusion and chylous ascites may occur but these reflect the severe end of the clinical spectrum. In some, diarrhea occurs with steatorrhea along with increased fecal loss of protein, reflected in increased fecal alpha-1-antitrypsin levels, while others may present with iron deficiency anemia, sometimes associated with occult small intestinal bleeding. Most lymphangiectasia in adults detected in recent years, however, appears to have few or no clinical features of malabsorption. Diagnosis remains dependent on endoscopic changes confirmed by small bowel biopsy showing histological evidence of intestinal lymphangiectasia. In some, video capsule endoscopy and enteroscopy have revealed more extensive changes along the length of the small intestine. A critical diagnostic element in adults with lymphangiectasia is the exclusion of entities (e.g. malignancies including lymphoma) that might lead to obstruction of the lymphatic system and “secondary” changes in the small bowel biopsy. In addition, occult infectious (e.g. Whipple’s disease from Tropheryma whipplei) or inflammatory disorders (e.g. Crohn’s disease) may also present with profound changes in intestinal permeability and protein-losing enteropathy that also require exclusion. Conversely, rare B-cell type lymphomas have also been described even decades following initial diagnosis of intestinal lymphangiectasia. Treatment has been historically defined to include a low fat diet with medium-chain triglyceride supplementation that leads to portal venous rather than lacteal uptake. A number of other pharmacological measures have been reported or proposed but these are largely anecdotal. Finally, rare reports of localized surgical resection of involved areas of small intestine have been described but follow-up in these cases is often limited.
Freeman, Hugh James; Nimmo, Michael
The effect of exposure of an intestinal epithelial cell line to various concentrations of ethanol (217 mM (1%) to 652 mM (3%)) during 24, 48, and 72 hr was investigated in vitro using a rat intestinal epithelial cell line (IRD 98). Incubation of these cells in the presence of ethanol significantly decreased cell growth. This inhibition was accompanied by a strong increase in cellular protein. Stimulation of specific disaccharidases, gamma-glutamyl transferase, and aminopeptidase activities by ethanol was dose- and time-dependent. Ethanol induces a change in the relative proportions of the different lipid classes synthesized; triglycerides, fatty acids, and cholesterol esters were preferentially synthethysed. Our findings show that cell lines are good models for investigation of the effects of ethanol, and that alcohol considerably modifies the functions of intestinal epithelial cells.
Nano, J.L.; Cefai, D.; Rampal, P. (Laboratoire de Gastroenterologie et de Nutrition, U.E.R. de Medecine, Nice (France))
Ethanol is an alcohol made from grain that can be blended with gasoline to extend petroleum supplies and to increase gasoline octane levels. Congressional proposals to encourage greater use of alternative fuels could increase the demand for ethanol. This report evaluates the growth potential of the ethanol industry to meet future demand increases and the impacts increased production would have on American agriculture and the federal budget. It is found that ethanol production could double or triple in the next eight years, and that American farmers could provide the corn for this production increase. While corn growers would benefit, other agricultural segments would not; soybean producers, for example could suffer for increased corn oil production (an ethanol byproduct) and cattle ranchers would be faced with higher feed costs because of higher corn prices. Poultry farmers might benefit from lower priced feed. Overall, net farm cash income should increase, and consumers would see slightly higher food prices. Federal budget impacts would include a reduction in federal farm program outlays by an annual average of between $930 million (for double current production of ethanol) to $1.421 billion (for triple production) during the eight-year growth period. However, due to an partial tax exemption for ethanol blended fuels, federal fuel tax revenues could decrease by between $442 million and $813 million.
Intestinal occlusion is defined as an independent predictive factor of intra-abdominal hypertension (IAH) which represents an independent predictor of mortality. Baggot in 1951 classified patients operated with intestinal occlusion as being at risk for IAH ("abdominal blow-out"), recommending them for open abdomen surgery proposed by Ogilvie. Abdominal surgery provokes IAH in 44.7% of cases with mortality which, in emergency, triples with respect to elective surgery (21.9% vs 6.8%). In particular, IAH is present in 61.2% of ileus and bowel distension and is responsible for 52% of mortality (54.8% in cases with intra-abdominal infection). These patients present with an increasing intra-abdominal pressure (IAP) which, over 20-25 mmHg, triggers an Abdominal Compartment Syndrome (ACS) with altered functions in some organs arriving at Multiple Organ Dysfunction Syndrome (MODS). The intestine normally covers 58% of abdominal volume but when there is ileus distension, intestinal pneumatosis develops (third space) which can occupy up to 90% of the entire cavity. At this moment, Gastro Intestinal Failure (GIF) can appear, which is a specific independent risk factor of mortality, motor of "Organ Failure". The pathophysiological evolution has many factors in 45% of cases: intestinal pneumatosis is associated with mucosal and serous edema, capillary leakage with an increase in extra-cellular volume and peritoneal fluid collections (fourth space). The successive loss of the mucous barrier permits a bacterial translocation which includes bacteria, toxins, pro-inflammatory factors and oxygen free radicals facilitating the passage from an intra-abdominal to inter-systemic vicious cyrcle. IAH provokes the raising of the diaphragm, and vascular and visceral compressions which induce hypertension in the various spaces with compartmental characteristics. These trigger hypertension in the renal, hepatic, pelvic, thoracic, cardiac, intracranial, orbital and lower extremity areas, giving a critical clinical condition of Polycompartment Syndrome. The monitoring of Abdominal Perfusion Pressure (APP) is more correct than the measurement of IAP because it reveals hydrodynamic alterations in the abdominal compartment. The APP (MAP-IAP) depends on arterial flow, venous outflow and capacity of the abdominal compartments response to increased internal volumes. The medical therapy used to decrease IAH and to contrast ACS is intestinal decompression with gastric and rectal tube; colonic endoscopic detention; correction of electrolytic abnormalities and prokinetic agents. Surgery, besides being decompressive and resolutive, must prevent a recurrence of ACS through the "tension-free closure" procedure. PMID:20476671
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
Background Antibiotic associated diarrhea and Clostridium difficile infection are frequent complications of broad spectrum antibiotic therapy. Probiotic bacteria are used as therapeutic and preventive agents in these disorders, but the exact functional mechanisms and the mode of action are poorly understood. The effects of clindamycin and the probiotic mixture VSL#3 (containing the 8 bacterial strains Streptococcus thermophilus, Bifidobacterium breve, Bifidobacterium longum, Bifidobacterium infantis, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus paracasei and Lactobacillus delbrueckii subsp. Bulgaricus) consecutively or in combination were investigated and compared to controls without therapy using a standardized human fecal microbiota in a computer-controlled in vitro model of large intestine. Microbial metabolites (short chain fatty acids, lactate, branched chain fatty acids, and ammonia) and the intestinal microbiota were analyzed. Results Compared to controls and combination therapy, short chain fatty acids and lactate, but also ammonia and branched chain fatty acids, were increased under probiotic therapy. The metabolic pattern under combined therapy with antibiotics and probiotics had the most beneficial and consistent effect on intestinal metabolic profiles. The intestinal microbiota showed a decrease in several indigenous bacterial groups under antibiotic therapy, there was no significant recovery of these groups when the antibiotic therapy was followed by administration of probiotics. Simultaneous application of anti- and probiotics had a stabilizing effect on the intestinal microbiota with increased bifidobacteria and lactobacilli. Conclusions Administration of VSL#3 parallel with the clindamycin therapy had a beneficial and stabilizing effect on the intestinal metabolic homeostasis by decreasing toxic metabolites and protecting the endogenic microbiota from destruction. Probiotics could be a reasonable strategy in prevention of antibiotic associated disturbances of the intestinal homeostasis and disorders.
One method of investigating the genetic etiology of alcoholism is to study individuals who were separated soon after birth from their alcoholic biological parents. The author and his colleagues conducted a series of such studies in Denmark; they concluded that, despite little exposure to the alcoholic biological parent, the sons of alcoholics were about four times more likely to be alcoholic than were the sons of nonalcoholics. They also found that having an alcoholic biological parent did not increase the sons' risk of developing psychiatric disorders other than alcoholism. After reviewing the results of four other studies that resemble the Danish series, the author discusses two investigations of the possible mode of transmission of alcoholism and describes further evidence for the proposed diagnostic category of familial alcoholism. PMID:6357988
Goodwin, D W
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.
Twin studies have established that there are substantial genetic influences on alcoholism (0.5-0.6) in both men and women. Our knowledge of behaviors predisposing to alcoholism, including anxiety and impulsivity, is advancing rapidly through animal and human studies. Although alcoholism is often comorbid with other substance abuse and psychiatric disorders, recent studies have shown that, with the exception of nicotine, the heritability of alcoholism is largely substance-specific. Increasing understanding of the neurobiology of addiction has identified neural pathways in which genetic variation at candidate genes could influence vulnerability. Some functional variants of these genes have been identified. Recent linkage analyses in humans and rodents have pointed to genomic regions harboring genes that influence alcoholism. Refinement of clinical phenotypes and use of intermediate phenotypes will improve chances of gene identification. All these advances in the understanding of the genetics of alcoholism should facilitate the development of more accurately targeted therapies using molecular diagnostic approaches. PMID:11276410
Enoch, M A; Goldman, D
The oligosaccharides 2-fucosyllactose and 3-fucosyllactose are major constituents of human breast milk but are not found in mouse milk. Milk oligosaccharides have a prebiotic action, thus affecting the colonisation of the infant intestine by microbiota. To determine the specific effect of fucosyllactose exposure on intestinal microbiota in mice, in the present study, we orally supplemented newborn mice with pure 2-fucosyllactose and 3-fucosyllactose. Exposure to 2-fucosyllactose and 3-fucosyllactose increased the levels of bacteria of the Porphyromonadaceae family in the intestinal gut, more precisely members of the genus Barnesiella as analysed by 16S pyrosequencing. The ability of Barnesiella to utilise fucosyllactose as energy source was confirmed in bacterial cultures. Whereas B. intestinihominis and B. viscericola did not grow on fucose alone, they proliferated in the presence of 2-fucosyllactose and 3-fucosyllactose following the secretion of linkage-specific fucosidase enzymes that liberated lactose. The change in the composition of intestinal microbiota mediated by fucosyllactose supplementation affected the susceptibility of mice to dextran sulphate sodium-induced colitis, as indicated by increased resistance of mice subjected to 2-fucosyllactose supplementation for 6 weeks. The present study underlines the ability of specific milk oligosaccharides to change the composition of intestinal microbiota and thereby to shape an intestinal milieu resilient to inflammatory diseases. PMID:24411010
Weiss, Gisela A; Chassard, Christophe; Hennet, Thierry
Irritable bowel syndrome (IBS) is a functional bowel disorder without any structural or metabolic abnormalities that sufficiently explain the symptoms, which include abdominal pain and discomfort, and bowel habit changes such as diarrhea and constipation. Its pathogenesis is multifactorial: visceral hypersensitivity, dysmotility, psychosocial factors, genetic or environmental factors, dysregulation of the brain-gut axis, and altered intestinal microbiota have all been proposed as possible causes. The human intestinal microbiota are composed of more than 1000 different bacterial species and 1014 cells, and are essential for the development, function, and homeostasis of the intestine, and for individual health. The putative mechanisms that explain the role of microbiota in the development of IBS include altered composition or metabolic activity of the microbiota, mucosal immune activation and inflammation, increased intestinal permeability and impaired mucosal barrier function, sensory-motor disturbances provoked by the microbiota, and a disturbed gut-microbiota-brain axis. Therefore, modulation of the intestinal microbiota through dietary changes, and use of antibiotics, probiotics, and anti-inflammatory agents has been suggested as strategies for managing IBS symptoms. This review summarizes and discusses the accumulating evidence that intestinal microbiota play a role in the pathophysiology and management of IBS.
Lee, Kang Nyeong; Lee, Oh Young
... his or her general health status. This Alcohol Alert reviews some common disorders associated with alcohol–related ... 73, 1994. Resources Source material for this Alcohol Alert originally appeared in the journal Alcohol Research & Health, “ ...
Objective. Balloon enteroscopy (BE) and capsule enteroscopy (CE) are enteroscopy methods that allow examination and treatment of the small bowel. Before the CE and BE era, the small intestine was difficult to access for investigation. Small intestinal tumours are infrequent conditions, but about half of them are malignant. Materials and Methods. A total of 303 BEs were performed in 179 patients. Oral insertion was performed in 240 and anal in 63 BEs. Indications for the procedure in our patients with small bowel tumours were anaemia and/or bleeding, obstruction, suspicion of carcinoid tumour, or suspicion of Peutz-Jeghers syndrome. Results. In 50 of our 179 patients (28%), we diagnosed some small intestinal tumours: hamartomas in Peutz-Jeghers syndrome in 16 patients, adenocarcinoma in 7, lymphoma in 6, carcinoid tumour in 4, melanoma and stromal tumour in 3, adenoma, lipoma, and inflammatory polyps in 2, and granular cell tumour, cavernous lymphangioma, fibrolipoma, Cronkhite-Canada polyps, and metastatic involvement in individual cases. Conclusion. BE facilitates exploration and treatment of the small intestine. The procedure is generally safe and useful. BE and CE are essential modalities for the management of small intestinal diseases.
Kopacova, Marcela; Bures, Jan; Tacheci, Ilja
Objective. Balloon enteroscopy (BE) and capsule enteroscopy (CE) are enteroscopy methods that allow examination and treatment of the small bowel. Before the CE and BE era, the small intestine was difficult to access for investigation. Small intestinal tumours are infrequent conditions, but about half of them are malignant. Materials and Methods. A total of 303 BEs were performed in 179 patients. Oral insertion was performed in 240 and anal in 63 BEs. Indications for the procedure in our patients with small bowel tumours were anaemia and/or bleeding, obstruction, suspicion of carcinoid tumour, or suspicion of Peutz-Jeghers syndrome. Results. In 50 of our 179 patients (28%), we diagnosed some small intestinal tumours: hamartomas in Peutz-Jeghers syndrome in 16 patients, adenocarcinoma in 7, lymphoma in 6, carcinoid tumour in 4, melanoma and stromal tumour in 3, adenoma, lipoma, and inflammatory polyps in 2, and granular cell tumour, cavernous lymphangioma, fibrolipoma, Cronkhite-Canada polyps, and metastatic involvement in individual cases. Conclusion. BE facilitates exploration and treatment of the small intestine. The procedure is generally safe and useful. BE and CE are essential modalities for the management of small intestinal diseases. PMID:24348540
Kopá?ová, Marcela; Rejchrt, Stanislav; Bureš, Jan; Tachecí, Ilja
BackgroundIntestinal barrier dysfunction and translocation of endotoxins are involved in the pathogenesis of alcoholic liver disease. Exposure to ethanol and its metabolite, acetaldehyde at relatively high concentrations have been shown to disrupt intestinal epithelial tight junctions in the conventional two dimensional cell culture models. The present study investigated quantitatively and qualitatively the effects of ethanol at concentrations detected in the
Elhaseen Elamin; Daisy Jonkers; Kati Juuti-Uusitalo; Sven van IJzendoorn; Freddy Troost; Hans Duimel; Jos Broers; Fons Verheyen; Jan Dekker; Ad Masclee
Alcohol is a factor in many categories of injury. Alcohol intoxication is frequently associated with injuries from falls, fires, drowning, overdoses, physical and sexual abusements, occupational accidents, traffic accidents and domestic violence. In many instances, for forensic purpose, it may be necessary to establish whether the patients have consumed alcohol that would have been the reason for the injury/accidents. Combining rapidity and reliability, alcohol saliva strip test (AST) has been put forward for the detection of alcohol in saliva for blood alcohol concentration (BAC). PMID:24783167
Thokala, Madhusudhana Rao; Dorankula, Shyam Prasad Reddy; Muddana, Keertrthi; Velidandla, Surekha Reddy
Alcohol is a factor in many categories of injury. Alcohol intoxication is frequently associated with injuries from falls, fires, drowning, overdoses, physical and sexual abusements, occupational accidents, traffic accidents and domestic violence. In many instances, for forensic purpose, it may be necessary to establish whether the patients have consumed alcohol that would have been the reason for the injury/accidents. Combining rapidity and reliability, alcohol saliva strip test (AST) has been put forward for the detection of alcohol in saliva for blood alcohol concentration (BAC).
Thokala, Madhusudhana Rao; Dorankula, Shyam Prasad Reddy; Muddana, Keertrthi; Velidandla, Surekha Reddy
Alcoholism, a worldwide disorder, is the cause of a variety of neurologic disorders. In this article we discuss the cellular pathophysiology of ethanol addition and abuse as well as evidence supporting and refuting the role of inheritance in alcoholism. A genetic marker for alcoholism has not been identified, but neurophysiologic studies may be promising. Some neurologic disorders related to longterm alcoholism are due predominantly to inadequate nutrition (the thiamine deficiency that causes Wernicke's encephalopathy), but others appear to involve the neurotoxicity of ethanol on brain (alcohol withdrawal syndrome and dementia) and peripheral nerves (alcoholic neuropathy and myopathy). Images
Diamond, I; Messing, R O
The intestinal mucosa functions as a defensive barrier that limits dietary antigen transport and microbial pathogens from colonizing enterocytes. The potential role of lactic acid bacteria, specifically Bifidobacteria, in probiotic and prebiotic functional food supplements is reviewed in the context of bacterial colonization, adherence, and disease prevention. This article reviews the mechanisms of action and optimization of methods that will
W. Allan Walker; Linda C. Duffy
BACKGROUNDChildren with chronic intestinal pseudo-obstruction (CIPO) often require total parenteral nutrition (TPN) which puts them at risk of liver failure and recurrent line infections. Intestinal transplantation has become a therapeutic option for TPN dependent children with intestinal failure who are failing management with TPN.AIMSTo investigate the outcome of children with CIPO referred for intestinal transplantation.METHODSA retrospective review was carried out
L Sigurdsson; J Reyes; S A Kocoshis; G Mazariegos; K M Abu-Elmagd; J Bueno; C Di Lorenzo
The intestinal epithelium is in direct contact with a vast microbiota, yet little is known about how epithelial cells defend the host against the heavy bacterial load. To address this question we studied Paneth cells, a key small intestinal epithelial lineage. We found that Paneth cells directly sense enteric bacteria through cell-autonomous MyD88-dependent toll-like receptor (TLR) activation, triggering expression of multiple antimicrobial factors. Paneth cells were essential for controlling intestinal barrier penetration by commensal and pathogenic bacteria. Furthermore, Paneth cell-intrinsic MyD88 signaling limited bacterial penetration of host tissues, revealing a role for epithelial MyD88 in maintaining intestinal homeostasis. Our findings establish that gut epithelia actively sense enteric bacteria and play an essential role in maintaining host-microbial homeostasis at the mucosal interface.
Vaishnava, Shipra; Behrendt, Cassie L.; Ismail, Anisa S.; Eckmann, Lars; Hooper, Lora V.
In this paper, we present a method to classify hyperplastic and adenomatous polyps of large intestine semiautomatically. First, doctors locate the contour of the original polyp images by using other software package. We determine if there are gores on the polyp by using modified Sobel operator on eliminating specular reflection pixels of original color images. We then get the polyp's texture by summing the gradient magnitude of pixels within the polyps. After detecting the actual contour of the polyps, we can determined if the polyp's contour is obvious or not (i.e. if the polyp bulges smoothly or not). We then observe whether the polyp's color is redder than or whiter than its neighbors. Finally, we classify the polyp of the intestine by applying the above steps. The flow chart of classification is as shown. We apply our method on 77 color images with polyps of the intestine and compare the results with a doctor's diagnosis.
Chou, Shih-Chen; Fuh, Chiou-Shann; Shieh, Ming J.
Intestinal polyposis, a precancerous neoplasia, results primarily from an abnormal increase in the number of crypts, which contain intestinal stem cells (ISCs). In mice, widespread deletion of the tumor suppressor Phosphatase and tensin homolog (PTEN) generates hamartomatous intestinal polyps with epithelial and stromal involvement. Using this model, we have established the relationship between stem cells and polyp and tumor formation.
Xi C He; Tong Yin; Justin C Grindley; Qiang Tian; Toshiro Sato; W Andy Tao; Raminarao Dirisina; Kimberly S Porter-Westpfahl; Mark Hembree; Teri Johnson; Leanne M Wiedemann; Terrence A Barrett; Leroy Hood; Hong Wu; Linheng Li
... people with liver disease, cancer, or blood clotting disorders. Low blood pressure: Very low blood pressure in patients who already have narrowing of the intestinal arteries may also cause intestinal ischemia. This often occurs in people with other serious ...
The gut microbiota obtained after birth is composed of a large range of bacteria that play different roles in the human host, such as nutrient uptake, protection against pathogens and immune modulation. The intestinal bacterial content is not completely known, but it is influenced by internal, and mainly by external factors, which modulate its composition and function. Studies indicate that the gut microbiota differs in lean and obese individuals, and in individuals with different food habits. There is evidence that the relationship between diet, inflammation, insulin resistance, and cardiometabolic risk are, in part, mediated by the composition of intestinal bacteria. Knowledge about the gut microbiota may result in different strategies to manipulate bacterial populations and promote health. This review discusses the relevance of understanding the role of dietary factors or patterns in the composition of the microbiota, as well as pathophysiological mechanisms of chronic metabolic diseases, and the potential of prebiotics and probiotics on the cardiometabolic risk profile. PMID:24936725
Moraes, Ana Carolina Franco de; Silva, Isis Tande da; Almeida-Pititto, Bianca de; Ferreira, Sandra Roberta G
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.
Pantoja-Feliciano, Ida Gisela; Clemente, Jose C; Costello, Elizabeth K; Perez, Maria E; Blaser, Martin J; Knight, Rob; Dominguez-Bello, Maria Gloria
Aqueous suspensions of Staphylococcus aureus were deposited on a Millipore filter and then exposed for a few seconds to 70% ethyl alcohol. Viable counts of bacteria extracted from the filter immediately after exposure to alcohol, and, in replicate experiments, after a further period of 3 h, showed that the mean immediate reduction of 97.6% in viable counts after treatment with alcohol was followed by a further mean reduction of 67.1% in the further 3 h holding time; the same bacterial suspensions allowed to dry on Millipore filters without exposure to alcohol showed a significantly smaller mean reduction in viable counts (34.3%) during a further 3 h holding time. These findings support the view that the reported further fall in numbers of bacteria on hands while wearing gloves for 3 h after alcohol disinfection can be explained by sublethal damage to some of the bacteria, from which they can recover only if promptly inoculated on culture medium.
Lilly, H. A.; Lowbury, E. J.; Wilkins, M. D.; Zaggy, A.
The impact of alcohol consumption on human health is complex and modulated by several factors such as patterns and amount of drinking, genetics, the organ system studied, as well as the sex and age of the user. There is strong evidence that chronic ethanol abuse is associated with increased morbidity and mortality, immunosuppression and increased susceptibility to both bacterial and viral infections. In contrast, moderate alcohol consumption exerts positive effects including decreased mortality, and improved cardiovascular disease and insulin sensitivity. Interestingly, accumulating evidence also supports an immune-boosting effect of moderate alcohol. In this editorial, we summarize the findings that support a positive effect of moderate alcohol on host immunity. We also discuss the limitations of the previous data and emphasize the importance of additional studies to uncover mechanisms for these immune-stimulating effects in order to extend these benefits to vulnerable segments of the population who cannot consume alcohol. PMID:24872009
Messaoudi, Ilhem; Pasala, Sumana; Grant, Kathleen
Sutureless intestinal anastomoses can be achieved either by compression, where two inverted rings of bowel are compressed by a hollow circular device that subsequently sloughs away and is passed anally, or by the use of tissue glues or laser welding. Compression devices used clinically with success are the Valtrac biofragmentable anastomotic ring, the polypropylene rings described by Rosati and the AKA guns. Glued anastomoses have only been used in animals and seem to be unsafe. However, laser-welded intestinal anastomoses appear highly promising in experimental studies and further development of this technique is warranted. PMID:1760684
McCue, J L; Phillips, R K
Bacterial vaginosis (BV) is the most common of the vaginitides affecting women of reproductive age. It appears to be due to an alteration in the vaginal ecology by which Lactobacillus spp., the predominant organisms in the healthy vagina, are replaced by a mixed flora including Prevotella bivia, Prevotella disiens, Porphyromonas spp., Mobiluncus spp., and Peptostreptococcus spp. All of these organisms except Mobiluncus spp. are also members of the endogenous vaginal flora. While evidence from treatment trials does not support the notion that BV is sexually transmitted, recent studies have shown an increased risk associated with multiple sexual partners. It has also been suggested that the pathogenesis of BV may be similar to that of urinary tract infections, with the rectum serving as a reservoir for some BV-associated flora. The organisms associated with BV have also been recognized as agents of female upper genital tract infection, including pelvic inflammatory disease, and the syndrome BV has been associated with adverse outcome of pregnancy, including premature rupture of membranes, chorioamnionitis, and fetal loss; postpartum endometritis; cuff cellulitis; and urinary tract infections. The mechanisms by which the BV-associated flora causes the signs of BV are not well understood, but a role for H2O2-producing Lactobacillus spp. in protecting against colonization by catalase-negative anaerobic bacteria has been recognized. These and other aspects of BV are reviewed.
Spiegel, C A
Intestinal injury from ionizing radiation is a clinically important entity, as enteritis symptoms occur commonly after radiotherapy for pelvic malignancies. Preventative or therapeutic options for radiation enteritis are mostly unsatisfactory; however, available data suggests that probiotic bacteria—those which confer health benefit—may have therapeutic value. Previous reports from both human trials and animal models have evaluated various end points for probiotic usage in limiting radiation-associated intestinal damage. Newer data suggests that particular probiotics and/or their secreted or derived bacterial products may have unique radioprotective properties. We will review the area with a focus on new developments surrounding probiotic therapy in radiation-induced intestinal injury and repair.
Ciorba, Matthew A.; Stenson, William F.
This review summarizes the evidence which supports the hypothesis that alcoholism is an inherited disease. (1) Genealogical studies showed that alcoholism is a family condition. (2) Studies of adopted children of alcoholic parents raised by foster parents demonstrated that family aggregation is of genetic nature. (3) Twin studies showed differences between identical and non-identical twins. (4) Alcoholism is associated with the following genetic markers: color vision, non-secretor ABH, HLA B13, and low platelet MAO. Markers may help lead to genetic primary prevention of alcoholism. (5) Biochemical studies showed the importance of alcohol dehydrogenase polymorphism in racial susceptibility to alcoholism. Three different general genetic models for alcoholism are described: (a) polygenic, (b) genetical heterogeneity, and (c) pharmacogenetic. PMID:6346123
Physicians are generally ill equipped to deal with alcoholism. This article describes ways in which alcoholism may be diagnosed, even when the patient does not admit to heavy drinking, and outlines methods of management, including a list of contraindicated drugs.
The black tiger shrimp (Penaeus monodon) is a marine crustacean of economic importance in the world market. To ensure sustainability of the shrimp industry, production capacity and disease outbreak prevention must be improved. Understanding healthy microbial balance inside the shrimp intestine can provide an initial step toward better farming practice and probiotic applications. In this study, we employed a barcode pyrosequencing analysis of V3-4 regions of 16S rRNA genes to examine intestinal bacteria communities in wild-caught and domesticated P. monodon broodstock. Shrimp faeces were removed from intestines prior to further analysis in attempt to identify mucosal bacterial population. Five phyla, Actinobacteria, Fusobacteria, Proteobacteria, Firmicutes and Bacteroidetes, were found in all shrimp from both wild and domesticated environments. The operational taxonomic unit (OTU) was assigned at 97% sequence identity, and our pyrosequencing results identified 18 OTUs commonly found in both groups. Sequences of the shared OTUs were similar to bacteria in three phyla, namely i) Proteobacteria (Vibrio, Photobacterium, Novosphingobium, Pseudomonas, Sphingomonas and Undibacterium), ii) Firmicutes (Fusibacter), and iii) Bacteroidetes (Cloacibacterium). The shared bacterial members in P. monodon from two different habitats provide evidence that the internal environments within the host shrimp also exerts selective pressure on bacterial members. Intestinal bacterial profiles were compared using denaturing gradient gel electrophoresis (DGGE). The sequences from DGGE bands were similar to those of Vibrio and Photobacterium in all shrimp, consistent with pyrosequencing results. This work provides the first comprehensive report on bacterial populations in the intestine of adult black tiger shrimp and reveals some similar bacterial members between the intestine of wild-caught and domesticated shrimp. PMID:24618668
Rungrassamee, Wanilada; Klanchui, Amornpan; Maibunkaew, Sawarot; Chaiyapechara, Sage; Jiravanichpaisal, Pikul; Karoonuthaisiri, Nitsara
After rutin (50–1500 mg\\/kg) was administered orally to rats, the relationship between its metabolites and mutagenicity was\\u000a investigated. Quercetin conjugates were detected in the urine of rats treated with more than 150 mg\\/kg. Administration of\\u000a rutin less than 100 mg\\/kg resulted in phenolic acid-like metabolites. However, intact rutin was not detected in the urine\\u000a of rats treated with different amounts.
Dong-Hyun Kim; Sang-Bum Han; Eun-Ah Bae; Myung Joo Han
Medically diagnosed alcoholics can be differentiated reliably from non-alcoholics using clinically laboratory tests. In the\\u000a present study, patients with liver diseases either due to alcohol or without alcohol compared with a group of normal healthy\\u000a persons. Heavy drinkers showed significantly lower body weight and percent body fat, and low BMI compared with other groups.\\u000a The percentage of hemoglobin and total
Subir Kumar Das; D. M. Vasudevan
The instability of vitamin A alcohol relative to vitamin A acetate has been studied in vivo and in vitro. Vitamin A alcohol is more unstable than vitamin A acetate in human gastric and duodenal juice and in rats' stomachs and intestines and is more marked at lower pH levels and in rats' stomachs. Alpha tocopherol improved the absorption curve of vitamin A alcohol in man by protecting it in gastric and duodenal juice. This protective effect could not be demonstrated in the rat.
Fitzgerald, Oliver; Fennelly, James J.; Hingerty, Daniel J.
Presents analysis of adult children of alcoholics, their experience and adjustment in relation to the severity and type of alcoholism, age considerations and perceptions as a child, and existence and nature of significant others. Discusses alcoholics' and others' family issues, focusing on roles taken, and personality characteristics. Emphasizes…
Goodman, Ronald W.
Adult children of alcoholics constitute the largest number of people affected by the disease of alcoholism. As a result of their childhood experiences they are high risk candidates not only for alcoholism in particular, but for a dysfunctional life style in general. This article discusses some of the characteristics that result from this environment, what the implications are in the
Janet Geringer Woititz
Alcohol use on campus and strategies colleges are using to educate students about alcohol are considered in two articles. In "When Alternatives Aren't," Ruth Bradford Burnham and Stephen J. Nelson explore the role alcoholic beverages play in young people's social lives and some of the implications for planning social events. They offer a balanced…
ACU-I Bulletin, 1984
... Alcoholism www.niaaa.nih.gov • 301.443.3860 Partial FAS This disorder includes some signs and symptoms of full FAS, but not all three. Most often, the growth issues are not present. Alcohol-Related Birth Defects (ARBD) This disorder includes alcohol-related physical abnormalities, ...
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 and…
Schuckit, Marc A.
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
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
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
Reports on Soviet parents' responses to a 1986 survey concerning parental influence on children and alcohol use. Points out that most parents perceive the link between their own alcohol use and children's drinking but cultural traditions and alcoholic habits often preclude change. Notes parents' opinions on effectiveness of governmental and school…
Levin, Boris Mikhailovich; Levin, Mikhail Borisovich
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.
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
Intestinal volvulus was recognized as the cause of death in 18 cetaceans, including 8 species of toothed whales (suborder Odontoceti). Cases originated from 11 institutions from around the world and included both captive (n = 9) and free-ranging (n = 9) animals. When the clinical history was available (n = 9), animals consistently demonstrated acute dullness 1 to 5 days prior to death. In 3 of these animals (33%), there was a history of chronic gastrointestinal illness. The pathological findings were similar to those described in other animal species and humans, and consisted of intestinal volvulus and a well-demarcated segment of distended, congested, and edematous intestine with gas and bloody fluid contents. Associated lesions included congested and edematous mesentery and mesenteric lymph nodes, and often serofibrinous or hemorrhagic abdominal effusion. The volvulus involved the cranial part of the intestines in 85% (11 of 13). Potential predisposing causes were recognized in most cases (13 of 18, 72%) but were variable. Further studies investigating predisposing factors are necessary to help prevent occurrence and enhance early clinical diagnosis and management of the condition. PMID:23150643
Begeman, L; St Leger, J A; Blyde, D J; Jauniaux, T P; Lair, S; Lovewell, G; Raverty, S; Seibel, H; Siebert, U; Staggs, S L; Martelli, P; Keesler, R I
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 to dry wood-derived litter sprayed with a mixture of sodium lignosulfonate, formic acid, and propionic acid. At five different times, five chickens from each pen were killed and the intestinal contents from ileum and caeca were collected. The samples were diluted and plated onto selective media to identify coliforms, Lactobacillus spp., Clostridium perfringens, and Enterococcus spp. Covariance analysis of bacterial counts showed significantly lower counts for C. perfringens in the caeca and the ileum and for Enterococcus spp. and Lactobacillus spp. in the ileum in chickens exposed to the acidified litter. Lactobacillus spp. showed significantly higher counts in the caeca in chickens exposed to acidified litter. There was no difference between the two litters with regard to coliforms in the ileum and the caeca or to Enterococcus spp. in the caeca. The study shows that exposing the chickens to acidified litter lowers the intestinal bacterial number, especially in the ileum, without negative consequences for the chicken's health or performance. Of special interest are the lower counts of C. perfringens and Enterococcus spp. that might reduce the risk of developing clinical or subclinical necrotic enteritis and growth depression.
Garrido, Margarita Novoa; Skjervheim, Magne; Oppegaard, Hanne; S?rum, Henning
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
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
A diffuse, acute enteritis developed in guinea pigs, preconditioned by starvation and opium, following intragastric administration of Salmonella typhimurium. The anatomic lesion depended on the invasion of the intestinal mucosa by the bacterial organisms....
A. Takeuchi H. Sprinz
Activation of innate immune systems including Toll-like receptor (TLR) signaling is a key in chronic liver disease. Recent studies suggest that gut microflora-derived bacterial products (i.e. lipopolysaccharide [LPS], bacterial DNA) and endogenous substances (i.e. high-mobility group protein B1 [HMGB1], free fatty acids) released from damaged cells activate hepatic TLRs that contribute to the development of alcoholic (ASH) and non-alcoholic steatohepatitis (NASH) and liver fibrosis. The crucial role of TLR4, a receptor for LPS, has been implicated in the development of ASH, NASH, liver fibrosis, and hepatocellular carcinoma. However, the role of other TLRs, such as TLR2 and TLR9 in chronic liver disease remains less clear. In this review, we will discuss the role of TLR2, 4, and 9 in Kupffer cells and hepatic stellate cells in the development of ASH, NASH, and hepatocarcinogenesis. PMID:23855294
Roh, Yoon Seok; Seki, Ekihiro
Alcohol is widely consumed; however, excessive use creates serious physical, psychological and social problems and contributes to the pathogenesis of many diseases. Alcohol use disorders (that is, alcohol dependence and alcohol abuse) are maladaptive patterns of excessive drinking that lead to serious problems. Abundant evidence indicates that alcohol dependence (alcoholism) is a complex genetic disease, with variations in a large number of genes affecting a person's risk of alcoholism. Some of these genes have been identified, including two genes involved in the metabolism of alcohol (ADH1B and ALDH2) that have the strongest known affects on the risk of alcoholism. Studies continue to reveal other genes in which variants affect the risk of alcoholism or related traits, including GABRA2, CHRM2, KCNJ6 and AUTS2. As more variants are analysed and studies are combined for meta-analysis to achieve increased sample sizes, an improved picture of the many genes and pathways that affect the risk of alcoholism will be possible. PMID:23712313
Edenberg, Howard J; Foroud, Tatiana
...National Institute on Alcohol Abuse and Alcoholism; Notice of Closed Meeting Pursuant...National Institute on Alcohol Abuse and Alcoholism Special Emphasis Panel; Review of Alcohol...National Institute on Alcohol Abuse & Alcoholism, National Institutes of Health,...
...National Institute on Alcohol Abuse and Alcoholism; Notice of Closed Meeting Pursuant...National Institute on Alcohol Abuse and Alcoholism Special Emphasis Panel; Alcohol Center...National Institute on Alcohol Abuse and Alcoholism, 5635 Fishers Lane, Room 2109,...
Previous studies could show a complex relationship between alcohol consumption and cognition but also with processes of ageing both social and biological. Acute effects of alcohol during intoxication include clinical signs such as excitation and reduced inhibition, slurred speech, and increased reaction time but also cognitive dysfunction, especially deficits in memory functions. However, these cognitive deficits during alcohol intoxication are reversible while patients with alcohol addiction and chronic alcohol intake show severe impairments of cognitive functions especially deficits in executive functions. Frontal executive impairments in these patients include deficits in problem solving, abstraction, planning, organizing, and working memory.Additionally, gender specific deficits are relevant for the course of the disease and its concomitant health problems with female alcoholics showing a higher vulnerability for cognitive dysfunction and brain atrophy at earlier stages of alcoholism history. PMID:23868552
Weiss, Elisabeth; Singewald, Evelin M; Ruepp, Beatrix; Marksteiner, Josef
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.
Over the last decade it became broadly recognized that adipokines and thus the fat tissue compartment exert a regulatory function on the immune system. Our own group described the pro-inflammatory function of the adipokine leptin within intestinal inflammation in a variety of animal models. Following-up on this initial work, the aim was to reveal stimuli and mechanisms involved in the activation of the fat tissue compartment and the subsequent release of adipokines and other mediators paralleled by the infiltration of immune cells. This review will summarize the current literature on the possible role of the mesenteric fat tissue in intestinal inflammation with a focus on Crohn’s disease (CD). CD is of particular interest in this context since the transmural intestinal inflammation has been associated with a characteristic hypertrophy of the mesenteric fat, a phenomenon called “creeping fat.” The review will address three consecutive questions: (i) What is inducing adipocyte activation, (ii) which factors are released after activation and what are the consequences for the local fat tissue compartment and infiltrating cells; (iii) do the answers generated before allow for an explanation of the role of the mesenteric fat tissue within intestinal inflammation? With this review we will provide a working model indicating a close interaction in between bacterial translocation, activation of the adipocytes, and subsequent direction of the infiltrating immune cells. In summary, the models system mesenteric fat indicates a unique way how adipocytes can directly interact with the immune system.
Kruis, Tassilo; Batra, Arvind; Siegmund, Britta
ABSTRACT Objective: Long intestinal tube splinting (LITS) is useful for clinically reducing the recurrence of adhesive small bowel obstruction (ASBO). However, a controversy exists whether LITS aggravates intestinal adhesions. This study evaluated the postoperative effects of LITS relative to simple enterolysis on intestinal adhesions in an experimental porcine model. Methods: A porcine model (n = 24) of dense intestinal adhesion was established by abrading the ileal wall with sterile P240 sandpaper. Enterolysis was performed on postoperative day 14. Animals were randomly divided into a group that underwent enterolysis only (control; n = 12) and those who underwent LITS as well as enterolysis (LITS; n = 12). The long intestinal tube was removed on post-LITS day 14, after abdominal radiography. All animals were euthanized on postenterolysis day 28 for assessment of intestinal adhesions using a semiquantitative macroscopic grading scale, hematoxylin-eosin histology, and hydroxyproline assay. Results: Prior to enterolysis, the experimentally induced intestinal adhesions of the two groups were similar in extent and severity. On postenterolysis day 28 the LITS and control groups were comparable with regard to adhesion loop length (p = .440), macroscopic adhesion severity (p = .820), serosal fibrosis grading (p = .450), and hydroxyproline content of the adhesion ileal segment (p = .630). Conclusion: Placement of the long intestinal tube did not aggravate intestinal adhesions over that of simple enterolysis in this intestinal adhesion porcine model. PMID:24785831
Li, Min; Wang, Gang; Zhou, Bo; Xia, Xianfeng; Li, Ning
Selective intestinal decontamination withnorfloxacin is useful in preventing spontaneousbacterial peritonitis in cirrhotic patients and also incirrhotic rats. The emergence of norfloxacin-resistantinfections in these patients warrants a search foralternative therapies. The aim of this study was toevaluate the effect of long-termtrimethoprimsulfamethoxazole administration on carbontetrachloride (CCl4)-induced cirrhosis inrats with specific attention to intestinal flora,bacterial translocation, spontaneous bacterialperitonitis (SBP), and survival. Male Sprague-Dawleyrats
Carlos Guarner; Bruce A. Runyon; Mary Heck; Sharon Young; Muhammad Y. Sheikh
Similar to effects of alcohol on the heart, liver, and brain, the effects of ethanol (EtOH) on lung injury are preventable. Unlike other vital organ systems, however, the lethal effects of alcohol on the lung are underappreciated, perhaps because there are no signs of overt pulmonary disorder until a secondary insult, such as a bacterial infection or injury, occurs in the lung. This paper provides overview of the complex changes in the alveolar environment known to occur following both chronic and acute alcohol exposures. Contemporary animal and cell culture models for alcohol-induced lung dysfunction are discussed, with emphasis on the effect of alcohol on transepithelial transport processes, namely, epithelial sodium channel activity (ENaC). The cascading effect of tissue and phagocytic Nadph oxidase (Nox) may be triggered by ethanol exposure, and as such, alcohol ingestion and exposure lead to a prooxidative environment; thus impacting alveolar macrophage (AM) function and oxidative stress. A better understanding of how alcohol changes the landscape of the alveolar epithelium can lead to improvements in treating acute respiratory distress syndrome (ARDS) for which hospitalized alcoholics are at an increased risk. PMID:23509726
Downs, Charles A; Trac, David; Brewer, Elizabeth M; Brown, Lou Ann; Helms, My N
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
The antimicrobial effectiveness of four hand-wash products for health care personnel included three liquid soaps that contained 4% chlorhexidine gluconate, 1% triclosan, or no antiseptic ingredient, respectively, and a 30% w/w ethyl alcohol-impregnated hand wipe. These products were evaluated for reduction in bacterial counts on hands after extended use of 15 handwashes per day for 5 consecutive days. The order of greatest to least log reduction among products at the end of the 5-day test period was chlorhexidine gluconate (2.01), triclosan (1.52), alcohol wipe (0.04), and control soap (0.03). Skin condition before and after handwash was assessed for each treatment group. Subjects reported less skin irritation with alcohol wipes than with the two antiseptic products. Repeated washing with alcohol wipes results in reductions in bacterial colony counts comparable with nonmedicated soap, sufficient to prevent transmission of pathogens by the hands in most situations that arise in nonacute health care settings. This evidence, in addition to increased user acceptability reported by the subjects who used alcohol wipes, suggests that alcohol wipes are an acceptable alternative to soap-and-water handwashing in nonacute health care settings. PMID:2337257
Butz, A M; Laughon, B E; Gullette, D L; Larson, E L
Great progress has been made by research on the contribution genetic factors make to a vulnerability toward alcoholism. Animal studies have demonstrated the importance of genetics in ethanol preference and levels of consumption, and human family, twin, and adoption research have revealed a 4-fold higher risk for offspring of alcoholics, even if they were adopted out at birth. The work presented in this symposium reviews the ongoing search for genetic trait markers of a vulnerability toward alcoholism. Dr. Li has used both animal and human research to demonstrate the possible importance of the genetic control of enzymes involved in ethanol metabolism and has worked to help develop an animal model of alcoholism. The possible importance of subgroups with different levels of predisposition toward alcoholism is emphasized by Dr. Cloninger. An overview of the studies of sons of alcoholics, given by Dr. Schuckit, reveals the potential importance of a decreased intensity of reaction to ethanol as part of a predisposition toward alcoholism and discusses the possible impact of some brain waves and ethanol metabolites to an alcoholism vulnerability. Dr. Deitrich reviews interrelationships between studies of animals and humans in the search for factors involved in a genetic vulnerability toward alcoholism. Taken together, these presentations underscore the importance of genetic factors in alcoholism, review animal and human research attempting to identify markers of a vulnerability, and reveal the high level of interaction between human and animal research. PMID:2936265
Schuckit, M A; Li, T K; Cloninger, C R; Deitrich, R A
Objective : To assess the impact of televised alcohol commercials on adolescents' alcohol use. Methods : Adolescents completed questionnaires about alcohol commercials and alcohol use in a prospective study. Results : A one standard deviation increase in viewing television programs containing alcohol commercials in seventh grade was associated…
Stacy, Alan W.; Zogg, Jennifer B.; Unger, Jennifer B.; Dent, Clyde W.
Despite the generally held view that alcohol is an unspecific pharmacological agent, recent molecular pharmacology studies demonstrated that alcohol has only a few known primary targets. These are the NMDA, GABAA, glycine, 5-hydroxytryptamine 3 (serotonin) and nicotinic ACh receptors as well as L-type Ca2+ channels and G-protein-activated inwardly rectifying K+ channels. Following this first hit of alcohol on specific targets in the brain, a second wave of indirect effects on a variety of neurotransmitter/neuropeptide systems is initiated that leads subsequently to the typical acute behavioural effects of alcohol, ranging from disinhibition to sedation and even hypnosis, with increasing concentrations of alcohol. Besides these acute pharmacodynamic aspects of alcohol, we discuss the neurochemical substrates that are involved in the initiation and maintenance phase of an alcohol drinking behaviour. Finally, addictive behaviour towards alcohol as measured by alcohol-seeking and relapse behaviour is reviewed in the context of specific neurotransmitter/neuropeptide systems and their signalling pathways. The activity of the mesolimbic dopaminergic system plays a crucial role during the initiation phase of alcohol consumption. Following long-term, chronic alcohol consumption virtually all brain neurotransmission seems to be affected, making it difficult to define which of the systems contributes the most to the transition from controlled to compulsive alcohol use. However, compulsive alcohol drinking is characterized by a decrease in the function of the reward neurocircuitry and a recruitment of antireward/stress mechanisms comes into place, with a hypertrophic corticotropin-releasing factor system and a hyperfunctional glutamatergic system being the most important ones.
Vengeliene, V; Bilbao, A; Molander, A; Spanagel, R
A characteristic feature of human intestinal spirochetosis (IS) is the colonization of the mucosa of the large intestine with intestinal spirochetes of the genus Brachyspira. The joining of the brachyspirae with the apical cellular membrane of enterocytes resembles in histological slides a false brush border of the intestinal mucosa. Various symptoms related to the involvement of the large gut were found with invasive IS. From the cultures of these cases were isolated Brachyspira aalborgii and B. pilosicoli. The frequency of the incidence of brachyspirae depended on the socio-economic living conditions of people. Colonization of the mucosa of the large gut was found more often in human populations in the developing countries; it was fairly rare in countries with high hygienic standards. An exception were men of homosexual orienation and patients presenting with a HIV infection. Isolation of brachyspirae from the faeces and biopsy of the mucosa of the large gut are fairly demanding jobs, especially with B. aalborgii. Most documented IS cases of this aetiology were diagnosed using immunohistochemical methods and amplification of the genus-specific region of the gene 16S rRNA. Isolation of B. pilosicoli tends to be simpler, it requires anaerobic incubation on selective blood agars for a period of 3-6 days at 37 degrees C. When manual haemoculture systems were used, patients in a critical state presented a translocation of brachyspirae into blood circulation, while automatic systems don't necessarily diagnose spirochetaemia. In the management of described cases of invasive IS particularly successful proved metronidazole and beta-lactam antibiotics. In isolated B. pilosicoli, in vitro tests confirmed sensitivity to metronidazole, ceftriaxone, meropenem, tetracycline, moxifloxacine and chloramphenicol. A varying frequency of resistance was found with clindamycin and amoxicillin, which how ever was efficacious in combination with clavulanic acid. PMID:15146383
Cízek, Alois; Lobová, Dana
Opinion statement The most common symptoms associated with intestinal gas are eructation, flatulence, abdominal bloating, and distention. Aerophagia\\u000a is an uncommon cause of eructation in which repetitive air swallowing results in belching, abdominal distention, and increased\\u000a flatus. Few therapies have been shown to be effective in treating these symptoms. Eructation can be treated by decreasing\\u000a excessive air swallowing. Occasionally, behavioral therapy
Michael P. Jones
This article is an enquiry into the current status of alcohol in Maltese culture. The responses of society to alcoholism depend on the way members of the community perceive the problems incurred by the use and abuse of a dependence producing substance like alcohol. These perceptions and subsequent responses are very much influenced by prevailing attitudes and beliefs. Malta is a melting point of cultures. This factor, together with a high density population and Malta's geopolitical strategic position, combine to make Malta a tolerant society. There is a laissez-faire response to alcoholism, at least partly due to the present inability to identify the need to take appropriate measures. The police force, medical profession and politicians still do not feel the responsibility or the need to provide effective laws and regulations, specialized treatment services or educative programmes on alcohol-related issues. A systematic enquiry is needed urgently to determine the severity and degree of the problems posed by alcohol abuse among the Maltese. Such an enquiry should be followed by a well planned national policy which includes local approaches and interventions. Finally, these interventions must be evaluated frequently and developed to achieve better results in the future. PMID:1912749
Baldacchino, A M
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 describe the compositions of fungal and bacterial rRNA genes from small and large intestines (tissue and luminal contents) of restricted-flora and specific-pathogen-free mice. OFRG analysis identified rRNA genes from all four major fungal phyla: Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. The largest assemblages of fungal rRNA sequences were related to the genera Acremonium, Monilinia, Fusarium, Cryptococcus/Filobasidium, Scleroderma, Catenomyces, Spizellomyces, Neocallimastix, Powellomyces, Entophlyctis, Mortierella, and Smittium and the order Mucorales. The majority of bacterial rRNA gene clones were affiliated with the taxa Bacteroidetes, Firmicutes, Acinetobacter, and Lactobacillus. Sequence-selective PCR analyses also detected several of these bacterial and fungal rRNA genes in the mouse chow. Fluorescence in situ hybridization analysis with a fungal small-subunit rRNA probe revealed morphologically diverse microorganisms resident in the mucus biofilm adjacent to the cecal and proximal colonic epithelium. Hybridizing organisms comprised about 2% of the DAPI (4',6-diamidino-2-phenylindole, dihydrochloride)-positive organisms in the mucus biofilm, but their abundance in fecal material may be much lower. These data indicate that diverse fungal taxa are present in the intestinal microbial community. Their abundance suggests that they may play significant roles in enteric microbial functions. PMID:16391120
Scupham, Alexandra J; Presley, Laura L; Wei, Bo; Bent, Elizabeth; Griffith, Natasha; McPherson, Michael; Zhu, Feilin; Oluwadara, Oluwadayo; Rao, Nagesh; Braun, Jonathan; Borneman, James
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.
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
Acute alcohol intoxication is a clinically harmful condition that usually follows the ingestion of a large amount of alcohol. Clinical manifestations are heterogeneous and involve different organs and apparatuses, with behavioral, cardiac, gastrointestinal, pulmonary, neurological, and metabolic effects. The management of an intoxicated patient occurs mainly in the emergency department and is aimed at stabilizing the clinical condition of the patient, depending on his/her clinical presentation. One specific drug that is useful in the treatment of acute alcohol intoxication is metadoxine, which is able to accelerate ethanol excretion. In patients presenting an acute alcohol intoxication, alcohol-related disorders should be detected so that the patient can be directed to an alcohol treatment unit, where a personalized, specific treatment can be established. PMID:19046719
Vonghia, Luisa; Leggio, Lorenzo; Ferrulli, Anna; Bertini, Marco; Gasbarrini, Giovanni; Addolorato, Giovanni
Heritability estimates for alcoholism range from 50% to 60%, pointing out the importance of genetic and environmental factors in its etiology. This review highlights recent advances in translational work investigating genetic influences on alcoholism. We focus on genetic research involving corticotropin-releasing factor, glutamatergic, and opioidergic systems. Variation in the CRF1 receptor gene has been shown to moderate stress-induced alcohol drinking (gene-environment interaction) in animals, and this finding was recently extended to humans. Also, the hyperglutamatergic state, first observed during withdrawal from chronic alcohol exposure in animal models, is associated with aversive and dysphoric states in alcoholics. Pharmacogenetic studies of naltrexone efficacy are in the clinical stages, and recent studies confirmed a differential response dependent on the mu-opioid receptor genotype. Such advances will be essential for the effective treatment of alcoholism in the future. PMID:19785977
Stacey, David; Clarke, Toni-Kim; Schumann, Gunter
An accidental poisoning due to drinking methyl alcohol in Chaoyang county is reported, analysing the accident. The poison came from the "retail white spirit" which was contaminated with methyl alcohol. Twenty-nine persons drank the wine, fourteen of them died, two of them became blind. After drinking this "retail white spirit" the drinkers showed symptoms of vertigo, headache, weakness, vomiting, night sweat, dyspnea and blurring of vision etc. within 6-120 hours. On examining the remaining spirit, we found the content of methyl alcohol to be between 16.6 and 40.69 g/100 ml. Some of the patients' urine and blood also contained methyl alcohol. We reckoned that each one of the twenty patients had taken more than 27 g of methyl alcohol and each of the ten dead drank more than 40 ml of the alcohol. PMID:2253526
Xiao, J H
In the Northern Plains of the United States, 100% of Indian reservations are affected by alcohol related problems. Approximately 90% of Native American adults are currently alcohol users or abusers or are recovering from alcohol abuse. Alcohol consumption has a devastating effect on the unborn. Fetal Alcohol Syndrome (FAS) is an irreversible birth…
This paper focuses on shedding light on three aspects--or faces--of alcoholism. The paper, in an interview format, presents the perspectives of the recovering alcoholic, a mother of the recovering alcoholic, and the adult child of an alcoholic. It also provides brief medical definitions of the various types of alcoholism. The paper points out that…
Alcohol abuse has numerous adverse health and social consequences. The consumer response to changes in alcohol affordability is an important issue on alcohol policy debates. Studies from many countries have shown an inverse relationship between alcohol prices and alcohol consumption in the population. There are, however, suggestions that increasing the price of alcohol by rising taxes may have limited effect on alcohol-related problems, associated with long-term heavy drinking. The aim of the present study was to evaluate the relationship between alcohol affordability and alcohol-related mortality rates in post-Soviet Belarus. For this purpose trends in alcohol-related mortality rates (mortality from liver cirrhosis, pancreatitis, alcoholism and alcohol psychoses) and affordability of vodka between 1990 and 2010 were compared. The time series analysis revealed that 1% increase in vodka affordability is associated with an increase in liver cirrhosis mortality of 0,77%, an increase in pancreatitis mortality of 0.53%, an increase in mortality from alcoholism and alcohol psychoses of 0,70%. The major conclusion emerging from this study is that affordability of alcohol is one of the most important predictor of alcohol-related problems in a population. These findings provide additional evidence that decreasing in affordability of alcohol is an effective strategy for reducing alcohol consumption and alcohol-related harm. PMID:23748944
Razvodovsky, Yury E
Background: Colon cancer is one of the most common forms of malignant tumors in humans, and its incidence is increasing. Since the intestinal microflora is directly in contact with the colonic cells, the enzymes of the bacterial microflora may also play a role in colon carcinogenesis. We studied the activity of bacterial enzymes in experimental colon cancer. Methods: Twenty milligrams
Namasivayam Nalini; Vaiyapuri Manju; Venugopal P. Menon
The concept of a biorefinery for higher-alcohol production is to integrate ethanol and methanol formation via fermentation\\u000a and biomass gasification, respectively, with, conversion of these simple alcohol intermediates into higher alcohols via the\\u000a Guerbet reaction. 1-Butanol results from the selfcondensation of ethanol in this multistep reaction occurring on a single\\u000a catalytic bed. Combining methanol with ethanol gives a mixture of
Edwin S. Olson; Ramesh K. Sharma; Ted R. Aulich
The purpose of the present study was to investigate whether sociopathic alcoholics respond differentially to different types of treatment. An earlier study found that alcoholics with antisocial personality disorder had somewhat better outcomes if treated in individually focused versus relationship-focused cognitive-behavioral treatment. The present study was designed to attempt to replicate these findings. One hundred and forty-nine alcoholics (42 of
David Kalman; Richard Longabaugh; Patrick R Clifford; Martha Beattie; Stephen A Maisto
The purpose of the study was to compare the antimicrobial efficacy of a silver nanoparticle gel versus and alcohol-based hand gel versus a combo gel in reducing transient bacterial counts isolated from hands seeded with S. marcescens.
Acute injury to the intestinal mucosa is a major dose-limiting complication of abdominal radiation therapy. We studied the role of the transcription factor NF-?B in protection against radiation-induced apoptosis in the intestinal epithelium in vivo. We use mice in which NF-?B signaling through I?B-kinase (IKK)-? is selectively ablated in intestinal epithelial cells to show that failure to activate epithelial cell NF-?B in vivo results in a significant increase in radiation-induced epithelial cell apoptosis. Furthermore, bacterial lipopolysaccharide, which is normally a radioprotective agent, is radiosensitizing in IKK?-deficient intestinal epithelial cells. Increased apoptosis in IKK?-deficient intestinal epithelial cells was accompanied by increased expression and activation of the tumor suppressor p53 and decreased expression of antiapoptotic Bcl-2 family proteins. These results demonstrate the physiological importance of the NF-?B system in protection against radiation-induced death in the intestinal epithelium in vivo and identify IKK? as a key molecular target for radioprotection in the intestine. Selective preactivation of NF-?B through IKK? in intestinal epithelial cells could provide a therapeutic modality that allows higher doses of radiation to be tolerated during cancer radiotherapy.
Egan, Laurence J.; Eckmann, Lars; Greten, Florian R.; Chae, Sungwon; Li, Zhi-Wei; Myhre, Gennett M.; Robine, Sylvie; Karin, Michael; Kagnoff, Martin F.
Describes a statewide continuing education program for emergency room nurses on the care of alcohol abusers. Covers planning and scheduling, resources, format and content, participants, and evaluation. (EM)
Cooper, Signe S.; Murphy, Julianne
The adverse effects of prenatal alcohol consumption have long been known; however, a formal description and clinical diagnosis of these effects was not introduced until 1973. Since then, the distinction of the wide range of effects that can be induced by prenatal alcohol exposure, and, consequently, the terminology to describe these effects has continued to evolve. Although much progress has been made in understanding the consequences of prenatal alcohol exposure, challenges still remain in properly identifying all affected individuals as well as their individual patterns of alcohol-induced deficits. Also, as the large numbers of women who continue to drink during pregnancy indicate, prevention efforts still require further refinement to enhance their effectiveness. In addition, the mechanisms underlying alcohol-induced damage have not yet been fully elucidated; as knowledge of the mechanisms underlying alcohol-induced deficits continues to grow, the possibility of minimizing potential harm by intervening during prenatal alcohol exposure is enhanced. Finally, researchers are exploring additional ways to improve or fully restore behavioral and cognitive functions disrupted by prenatal alcohol exposure by treating the individuals with fetal alcohol spectrum disorders, thereby reducing the heavy burden for affected individuals and their families.
Warren, Kenneth R.; Hewitt, Brenda G.; Thomas, Jennifer D.
AIM: To investigate the phasic alteration of intestinal homeostasis in an experimental model of intestinal obstruction. METHODS: A rabbit model of intestinal obstruction was established by transforming parts of an infusion set into an in vivo pulled-type locking clamp and creating a uniform controllable loop obstruction in the mesenteric non-avascular zone 8 cm from the distal end of the ileum. The phasic alteration of intestinal homeostasis was studied after intestinal obstruction. The changes in goblet cells, intraepithelial lymphocytes, lamina propria lymphocytes, and intestinal epithelium were quantified from periodic acid-Schiff-stained sections. Ornithine decarboxylase (ODC) activity and serum citrulline levels were measured by high-performance liquid chromatography. Claudin 1 mRNA expression was examined by real-time polymerase chain reaction analysis. Intestinal microorganisms, wet/dry weight ratios, pH values, and endotoxin levels were determined at multiple points after intestinal obstruction. Furthermore, the number and ratio of CD3+, CD4+ and CD8+ T cells were determined by flow cytometry, and secretory IgA levels were measured with an enzyme-linked immunosorbent assay. RESULTS: A suitable controllable rabbit model of intestinal obstruction was established. Intestinal obstruction induced goblet cell damage and reduced cell number. Further indicators of epithelial cell damage were observed as reduced serum citrulline levels and claudin 1 gene expression, and a transient increase in ODC activity. In addition, the wet/dry weight ratio and pH of the intestinal lumen were also dramatically altered. The ratio of Bacillus bifidus and enterobacteria was reversed following intestinal obstruction. The number and area of Peyer’s patches first increased then sharply decreased after the intestinal obstruction, along with an alteration in the ratio of CD4/CD8+ T cells, driven by an increase in CD3+ and CD8+ T cells and a decrease in CD4+ T cells. The number of lamina propria lymphocytes also gradually decreased with prolonged obstruction. CONCLUSION: Intestinal obstruction can induce disruption of intestinal homeostasis.
Yu, Xiang-Yang; Zou, Chang-Lin; Zhou, Zhen-Li; Shan, Tao; Li, Dong-Hua; Cui, Nai-Qiang
With the high prevalence of gastrointestinal disorders, there is great interest in establishing in vitro models of human intestinal disease and in developing drug-screening platforms that more accurately represent the complex physiology of the intestine. We will review how recent advances in developmental and stem cell biology have made it possible to generate complex, three-dimensional, human intestinal tissues in vitro through directed differentiation of human pluripotent stem cells. These are currently being used to study human development, genetic forms of disease, intestinal pathogens, metabolic disease and cancer. PMID:24496613
Wells, James M; Spence, Jason R
newsletter | contact Share | Nail Infection, Bacterial (Paronychia) Information for adults A A A Nail-fold swelling and large pus-filled lesions are typical ... bacterial paronychia. Overview Paronychia, commonly known as bacterial nail infection, is inflammation of the region of the ...
In this study, a total of 94 lactic acid bacterial (LAB) isolates of porcine small intestinal and fecal origin were screened for their probiotic properties. The aim was to evaluate whether their isolation site and putative species identity play a role in these characteristics and whether either of these can be used as a predictive factor for the probiotic potential
Tanja Lähteinen; Erja Malinen; Joanna M. K. Koort; Ulla Mertaniemi-Hannus; Tanja Hankimo; Ninja Karikoski; Soile Pakkanen; Hanna Laine; Hanna Sillanpää; Henna Söderholm; Airi Palva
The incorporation of intestinal segments into the urinary tract favors bacterial growth of the skin flora, anaerobic bacteria, and uropathogenic strains. The route of infection is ascending; bacteria enter the urethra or the abdominal stoma, which is followed by colonization of the reconstructed lower urinary tract. Bacteriuria is common in all kind of reconstructions; however, urine from neobladder patients with
Björn Wullt; William Agace; Wiking Mansson
Feeding of bovine milk to mice induced a high incidence of bacterial translocation from the intestines to the mesenteric lymph nodes, and the bacteria involved were mainly members of the family Enterobacteriaceae. Supplementation of the milk diet with bovine lactoferrin or a pepsin-generated hydrolysate of bovine lactoferrin resulted in significant suppression of bacterial translocation. Our findings suggest that this ability of lactoferrin to inhibit bacterial translocation may be due to its suppression of bacterial overgrowth in the guts of milk-fed mice.
Teraguchi, S; Shin, K; Ogata, T; Kingaku, M; Kaino, A; Miyauchi, H; Fukuwatari, Y; Shimamura, S
Beliefs about the effects of alcohol are termed alcohol outcome expectancies. In previous studies, stronger positive alcohol expectancies have been associated with increased drinking behavior, and alcohol abuse and dependence symptoms among alcohol users. The present study compared alcohol expectancies using the Alcohol Expectancy Questionnaire (AEQ) in women with a confirmed history of alcoholism in one or both parents (FHP)
Allison Leigh Dorlen
... Facts, causes, signs, diagnosis, and treatments. Research and Tracking Monitoring, prevention strategies, and other research. Data & Statistics ... Diagnosis Treatments Data & Statistics Alcohol Consumption Rates Research & Tracking Monitoring Alcohol Use Tracking Fetal Alcohol Syndrome Preventing ...
... Task Force on Fetal Alcohol Syndrome and Fetal Alcohol Effect Training & Education Articles & Key Findings Free Materials Multimedia ... have a mix of these. The term fetal alcohol effects (FAE) was previously used to describe intellectual disabilities ...
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.
Implicit in the central dogma is the hypothesis that each protein gene product has but one function. However, over the past decade, it has become clear that many proteins have one or more unique functions, over-and-above the principal biological action of the specific protein. This phenomenon is now known as protein moonlighting and many well-known proteins such as metabolic enzymes and molecular chaperones are now recognised as moonlighting proteins. A growing number of bacterial species are being found to have moonlighting proteins and the moonlighting activities of such proteins can contribute to bacterial virulence behaviour. The glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase (GAPD) and enolase, and the cell stress proteins: chaperonin 60, Hsp70 and peptidyl prolyl isomerase, are among the most common of the bacterial moonlighting proteins which play a role in bacterial virulence. Moonlighting activities include adhesion and modulation of cell signalling processes. It is likely that only the tip of the bacterial moonlighting iceberg has been sighted and the next decade will bring with it many new discoveries of bacterial moonlighting proteins with a role in bacterial virulence. PMID:22143554
Henderson, Brian; Martin, Andrew
Mutations in the Nod2 gene are among the strongest genetic risk factors in the pathogenesis of ileal Crohn's disease, but the exact contributions of Nod2 to intestinal mucosal homeostasis are not understood. Here we show that Nod2 plays an essential role in controlling commensal bacterial flora in the intestine. Analysis of intestinal bacteria from the terminal ilea of Nod2-deficient mice showed that they harbor an increased load of commensal resident bacteria. Furthermore, Nod2-deficient mice had a diminished ability to prevent intestinal colonization of pathogenic bacteria. In vitro, intestinal crypts isolated from terminal ilea of Nod2-deficient mice were unable to kill bacteria effectively, suggesting an important role of Nod2 signaling in crypt function. Interestingly, the expression of Nod2 is dependent on the presence of commensal bacteria, because mice re-derived into germ-free conditions expressed significantly less Nod2 in their terminal ilea, and complementation of commensal bacteria into germ-free mice induced Nod2 expression. Therefore, Nod2 and intestinal commensal bacterial flora maintain a balance by regulating each other through a feedback mechanism. Dysfunction of Nod2 results in a break-down of this homeostasis.
Petnicki-Ocwieja, Tanja; Hrncir, Tomas; Liu, Yuen-Joyce; Biswas, Amlan; Hudcovic, Tomas; Tlaskalova-Hogenova, Helena; Kobayashi, Koichi S.
BACKGROUND—Children with chronic intestinal pseudo-obstruction (CIPO) often require total parenteral nutrition (TPN) which puts them at risk of liver failure and recurrent line infections. Intestinal transplantation has become a therapeutic option for TPN dependent children with intestinal failure who are failing management with TPN.?AIMS—To investigate the outcome of children with CIPO referred for intestinal transplantation.?METHODS—A retrospective review was carried out of records and diagnostic studies from 27 patients with CIPO referred for intestinal transplantation.?RESULTS—Five children were not listed for transplantation: two because of parental decision, two because of suspicion of Munchausen syndrome by proxy, and one because he tolerated enteral nutrition. Six are still TPN dependent and awaiting transplantation. Eight children died awaiting transplantation. Eight children underwent transplantation. Three died (two months, seven months, and four years after transplant). Five children are alive with a median follow up of 2.6 years (range two months to six years). All transplanted children were able to tolerate full enteral feedings. The postoperative course was complicated by dumping syndrome, Munchausen syndrome by proxy, narcotic withdrawal, and uncovering of achalasia. Conclusion—Intestinal transplantation may be a life saving procedure in children with CIPO. Early referral and thorough pretransplant evaluation are keys to successful transplantation.???Keywords: intestinal transplantation; small bowel transplantation; children; chronic intestinal pseudo-obstruction; small bowel motility; total parenteral nutrition
Sigurdsson, L; Reyes, J; Kocoshis, S; Mazariegos, G; Abu-Elmagd, K; Bueno, J; Di, L
In vitro intestinal models can provide new insights into small intestinal function, including cellular growth and proliferation mechanisms, drug absorption capabilities, and host-microbial interactions. These models are typically formed with cells cultured on 2D scaffolds or transwell inserts, but it is widely understood that epithelial cells cultured in 3D environments exhibit different phenotypes that are more reflective of native tissue. Our focus was to develop a porous, synthetic 3D tissue scaffold with villous features that could support the culture of epithelial cell types to mimic the natural microenvironment of the small intestine. We demonstrated that our scaffold could support the co-culture of Caco-2 cells with a mucus-producing cell line, HT29-MTX, as well as small intestinal crypts from mice for extended periods. By recreating the surface topography with accurately sized intestinal villi, we enable cellular differentiation along the villous axis in a similar manner to native intestines. In addition, we show that the biochemical microenvironments of the intestine can be further simulated via a combination of apical and basolateral feeding of intestinal cell types cultured on the 3D models. Biotechnol. Bioeng. 2014;111: 1222-1232. © 2014 Wiley Periodicals, Inc. PMID:24390638
Costello, Cait M; Hongpeng, Jia; Shaffiey, Shahab; Yu, Jiajie; Jain, Nina K; Hackam, David; March, John C