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Author (up) Alcock, J.; Maley, C.C.; Aktipis, C.A. file  url
  Title Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms Type Journal Article
  Year 2014 Publication BioEssays : News and Reviews in Molecular, Cellular and Developmental Biology Abbreviated Journal Bioessays  
  Volume 36 Issue 10 Pages 940-949  
  Keywords Animals; *Biological Evolution; *Feeding Behavior; Gastrointestinal Tract/*microbiology; Humans; *Microbiota; Models, Biological; Obesity/etiology; Cravings; Evolutionary conflict; Host manipulation; Microbiome; Obesity  
  Abstract Microbes in the gastrointestinal tract are under selective pressure to manipulate host eating behavior to increase their fitness, sometimes at the expense of host fitness. Microbes may do this through two potential strategies: (i) generating cravings for foods that they specialize on or foods that suppress their competitors, or (ii) inducing dysphoria until we eat foods that enhance their fitness. We review several potential mechanisms for microbial control over eating behavior including microbial influence on reward and satiety pathways, production of toxins that alter mood, changes to receptors including taste receptors, and hijacking of the vagus nerve, the neural axis between the gut and the brain. We also review the evidence for alternative explanations for cravings and unhealthy eating behavior. Because microbiota are easily manipulatable by prebiotics, probiotics, antibiotics, fecal transplants, and dietary changes, altering our microbiota offers a tractable approach to otherwise intractable problems of obesity and unhealthy eating.  
  Call Number Serial 2002  
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Author (up) Bercik, P. file  url
  Title The microbiota-gut-brain axis: learning from intestinal bacteria? Type Journal Article
  Year 2011 Publication Gut Abbreviated Journal Gut  
  Volume 60 Issue 3 Pages 288-289  
  Keywords Animals; Bacterial Infections/*psychology; Cognition Disorders/*microbiology; Humans; Intestinal Diseases/microbiology/*psychology; Intestines/*microbiology; Mice; Symbiosis; Microbiome  
  Abstract The intestinal microbiota is a diverse and dynamic ecosystem,1 which has developed a mutualistic relationship with its host and plays a crucial role in the development of the host's innate and adaptive immune responses.2 This ecosystem serves the host by protecting against pathogens, harvesting otherwise inaccessible nutrients, aiding in neutralisation of drugs and carcinogens, and affecting the metabolism of lipids.3 Gut bacteria modulate intestinal motility, barrier function and visceral perception.4

An interaction between the intestinal microbiota and the central nervous system (CNS) may seem difficult to conceive at first sight, but clinicians are well aware of the benefit of oral antibiotics and laxatives in the treatment of hepatic encephalopathy.5 Data accumulated from animal studies indicate that there is central sensing of gastrointestinal infections. For example, acute infection with Campylobacter jejuni results in anxiety-like behaviour and rapid activation of vagal pathways prior to onset of immune responses,6 while chronic Helicobacter pylori infection in mice leads to abnormal feeding behaviour and upregulation of tumour necrosis factor α (TNFα) in the median eminence of the hypothalamus.7 Rapid and sustained gut�brain communication may confer a significant advantage to the host, as central activation in response to changes in commensals or pathogens would allow better control of gut function and immunity.
  Call Number Serial 2096  
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Author (up) Borre, Y.E.; Moloney, R.D.; Clarke, G.; Dinan, T.G.; Cryan, J.F. file  url
  Title The impact of microbiota on brain and behavior: mechanisms & therapeutic potential Type Journal Article
  Year 2014 Publication Advances in Experimental Medicine and Biology Abbreviated Journal Adv Exp Med Biol  
  Volume 817 Issue Pages 373-403  
  Keywords Animals; Anti-Bacterial Agents/pharmacology; *Behavior; Brain/*physiology; Brain Diseases/therapy; Cognition; Humans; Intestines/microbiology; Microbiome; Microbiota/*physiology; Probiotics/pharmacology; Signal Transduction; Tryptophan/metabolism  
  Abstract There is increasing evidence that host-microbe interactions play a key role in maintaining homeostasis. Alterations in gut microbial composition is associated with marked changes in behaviors relevant to mood, pain and cognition, establishing the critical importance of the bi-directional pathway of communication between the microbiota and the brain in health and disease. Dysfunction of the microbiome-brain-gut axis has been implicated in stress-related disorders such as depression, anxiety and irritable bowel syndrome and neurodevelopmental disorders such as autism. Bacterial colonization of the gut is central to postnatal development and maturation of key systems that have the capacity to influence central nervous system (CNS) programming and signaling, including the immune and endocrine systems. Moreover, there is now expanding evidence for the view that enteric microbiota plays a role in early programming and later response to acute and chronic stress. This view is supported by studies in germ-free mice and in animals exposed to pathogenic bacterial infections, probiotic agents or antibiotics. Although communication between gut microbiota and the CNS are not fully elucidated, neural, hormonal, immune and metabolic pathways have been suggested. Thus, the concept of a microbiome-brain-gut axis is emerging, suggesting microbiota-modulating strategies may be a tractable therapeutic approach for developing novel treatments for CNS disorders.  
  Call Number Serial 2003  
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Author (up) Brooks, J.P.; Adeli, A.; McLaughlin, M.R. file  url
  Title Microbial ecology, bacterial pathogens, and antibiotic resistant genes in swine manure wastewater as influenced by three swine management systems Type Journal Article
  Year 2014 Publication Water Research Abbreviated Journal Water Res  
  Volume 57 Issue Pages 96-103  
  Keywords Animal Husbandry/*methods; Animals; Anti-Bacterial Agents/pharmacology; Bacteria/drug effects/*genetics/*isolation & purification; Bacterial Proteins/genetics/metabolism; Drug Resistance, Bacterial/*genetics; Manure/*microbiology; Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/isolation & purification; *Microbiota; RNA, Ribosomal, 16S/genetics/metabolism; Real-Time Polymerase Chain Reaction; Southeastern United States; Sus scrofa; Waste Water/*microbiology; Antibiotic resistance; Campylobacter; Confined animal feeding operation (CAFO); Lagoon wastewater; Salmonella; Swine; Microbiome  
  Abstract The environmental influence of farm management in concentrated animal feeding operations (CAFO) can yield vast changes to the microbial biota and ecological structure of both the pig and waste manure lagoon wastewater. While some of these changes may not be negative, it is possible that CAFOs can enrich antibiotic resistant bacteria or pathogens based on farm type, thereby influencing the impact imparted by the land application of its respective wastewater. The purpose of this study was to measure the microbial constituents of swine-sow, -nursery, and -finisher farm manure lagoon wastewater and determine the changes induced by farm management. A total of 37 farms were visited in the Mid-South USA and analyzed for the genes 16S rRNA, spaQ (Salmonella spp.), Camp-16S (Campylobacter spp.), tetA, tetB, ermF, ermA, mecA, and intI using quantitative PCR. Additionally, 16S rRNA sequence libraries were created. Overall, it appeared that finisher farms were significantly different from nursery and sow farms in nearly all genes measured and in 16S rRNA clone libraries. Nearly all antibiotic resistance genes were detected in all farms. Interestingly, the mecA resistance gene (e.g. methicillin resistant Staphylococcus aureus) was below detection limits on most farms, and decreased as the pigs aged. Finisher farms generally had fewer antibiotic resistance genes, which corroborated previous phenotypic data; additionally, finisher farms produced a less diverse 16S rRNA sequence library. Comparisons of Camp-16S and spaQ GU (genomic unit) values to previous culture data demonstrated ratios from 10 to 10,000:1 depending on farm type, indicating viable but not cultivatable bacteria were dominant. The current study indicated that swine farm management schemes positively and negatively affect microbial and antibiotic resistant populations in CAFO wastewater which has future “downstream” implications from both an environmental and public health perspective.  
  Call Number Serial 1943  
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Author (up) Chen, X.; D'Souza, R.; Hong, S.-T. file  url
  Title The role of gut microbiota in the gut-brain axis: current challenges and perspectives Type Journal Article
  Year 2013 Publication Protein & Cell Abbreviated Journal Protein Cell  
  Volume 4 Issue 6 Pages 403-414  
  Keywords Brain/*metabolism; Central Nervous System/metabolism; Gastrointestinal Tract/*metabolism/microbiology; High-Throughput Nucleotide Sequencing; Humans; Liver/metabolism; Metabolic Diseases/metabolism/pathology; *Metagenome; Microbiome; Receptors, G-Protein-Coupled/metabolism  
  Abstract Brain and the gastrointestinal (GI) tract are intimately connected to form a bidirectional neurohumoral communication system. The communication between gut and brain, knows as the gut-brain axis, is so well established that the functional status of gut is always related to the condition of brain. The researches on the gut-brain axis were traditionally focused on the psychological status affecting the function of the GI tract. However, recent evidences showed that gut microbiota communicates with the brain via the gut-brain axis to modulate brain development and behavioral phenotypes. These recent findings on the new role of gut microbiota in the gut-brain axis implicate that gut microbiota could associate with brain functions as well as neurological diseases via the gut-brain axis. To elucidate the role of gut microbiota in the gut-brain axis, precise identification of the composition of microbes constituting gut microbiota is an essential step. However, identification of microbes constituting gut microbiota has been the main technological challenge currently due to massive amount of intestinal microbes and the difficulties in culture of gut microbes. Current methods for identification of microbes constituting gut microbiota are dependent on omics analysis methods by using advanced high tech equipment. Here, we review the association of gut microbiota with the gut-brain axis, including the pros and cons of the current high throughput methods for identification of microbes constituting gut microbiota to elucidate the role of gut microbiota in the gut-brain axis.  
  Call Number Serial 2005  
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Author (up) Dzidic, M.; Abrahamsson, T.R.; Artacho, A.; Bjorksten, B.; Collado, M.C.; Mira, A.; Jenmalm, M.C. file  url
  Title Aberrant IgA responses to the gut microbiota during infancy precede asthma and allergy development Type Journal Article
  Year 2017 Publication The Journal of Allergy and Clinical Immunology Abbreviated Journal J Allergy Clin Immunol  
  Volume 139 Issue 3 Pages 1017-1025.e14  
  Keywords Bacteria/isolation & purification; Bacterial Load; Child; Child, Preschool; Feces/*microbiology; Female; *Gastrointestinal Microbiome; Humans; Hypersensitivity/*immunology/*microbiology; Immunoglobulin A/*immunology; Infant; Male; Allergic disease; IgA index; IgA recognition patterns; asthma; childhood; gut microbiota; microbiome composition; secretory IgA  
  Abstract BACKGROUND: Although a reduced gut microbiota diversity and low mucosal total IgA levels in infancy have been associated with allergy development, IgA responses to the gut microbiota have not yet been studied. OBJECTIVE: We sought to determine the proportions of IgA coating together with the characterization of the dominant bacteria, bound to IgA or not, in infant stool samples in relation to allergy development. METHODS: A combination of flow cytometric cell sorting and deep sequencing of the 16S rDNA gene was used to characterize the bacterial recognition patterns by IgA in stool samples collected at 1 and 12 months of age from children staying healthy or having allergic symptoms up to 7 years of age. RESULTS: The children with allergic manifestations, particularly asthma, during childhood had a lower proportion of IgA bound to fecal bacteria at 12 months of age compared with healthy children. These alterations cannot be attributed to differences in IgA levels or bacterial load between the 2 groups. Moreover, the bacterial targets of early IgA responses (including coating of the Bacteroides genus), as well as IgA recognition patterns, differed between healthy children and children with allergic manifestations. Altered IgA recognition patterns in children with allergy were observed already at 1 month of age, when the IgA antibodies are predominantly maternally derived in breast-fed children. CONCLUSION: An aberrant IgA responsiveness to the gut microbiota during infancy precedes asthma and allergy development, possibly indicating an impaired mucosal barrier function in allergic children.  
  Call Number Serial 1933  
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Author (up) Ege, M.J.; Mayer, M.; Normand, A.-C.; Genuneit, J.; Cookson, W.O.C.M.; Braun-Fahrlander, C.; Heederik, D.; Piarroux, R.; von Mutius, E. file  url
  Title Exposure to environmental microorganisms and childhood asthma Type Journal Article
  Year 2011 Publication The New England Journal of Medicine Abbreviated Journal N Engl J Med  
  Volume 364 Issue 8 Pages 701-709  
  Keywords Adolescent; *Agriculture; Asthma/*epidemiology/immunology; Bacteria/*isolation & purification; Biodiversity; Child; Cross-Sectional Studies; Dust/analysis; Environmental Exposure/*analysis; Female; Fungi/*isolation & purification; Humans; Hypersensitivity/*epidemiology/immunology; Immunoglobulin E/blood; Logistic Models; Male; Microbiome; Polymorphism, Single-Stranded Conformational; Prevalence; Risk Factors; Surveys and Questionnaires  
  Abstract BACKGROUND: Children who grow up in environments that afford them a wide range of microbial exposures, such as traditional farms, are protected from childhood asthma and atopy. In previous studies, markers of microbial exposure have been inversely related to these conditions. METHODS: In two cross-sectional studies, we compared children living on farms with those in a reference group with respect to the prevalence of asthma and atopy and to the diversity of microbial exposure. In one study--PARSIFAL (Prevention of Allergy-Risk Factors for Sensitization in Children Related to Farming and Anthroposophic Lifestyle)--samples of mattress dust were screened for bacterial DNA with the use of single-strand conformation polymorphism (SSCP) analyses to detect environmental bacteria that cannot be measured by means of culture techniques. In the other study--GABRIELA (Multidisciplinary Study to Identify the Genetic and Environmental Causes of Asthma in the European Community [GABRIEL] Advanced Study)--samples of settled dust from children's rooms were evaluated for bacterial and fungal taxa with the use of culture techniques. RESULTS: In both studies, children who lived on farms had lower prevalences of asthma and atopy and were exposed to a greater variety of environmental microorganisms than the children in the reference group. In turn, diversity of microbial exposure was inversely related to the risk of asthma (odds ratio for PARSIFAL, 0.62; 95% confidence interval [CI], 0.44 to 0.89; odds ratio for GABRIELA, 0.86; 95% CI, 0.75 to 0.99). In addition, the presence of certain more circumscribed exposures was also inversely related to the risk of asthma; this included exposure to species in the fungal taxon eurotium (adjusted odds ratio, 0.37; 95% CI, 0.18 to 0.76) and to a variety of bacterial species, including Listeria monocytogenes, bacillus species, corynebacterium species, and others (adjusted odds ratio, 0.57; 95% CI, 0.38 to 0.86). CONCLUSIONS: Children living on farms were exposed to a wider range of microbes than were children in the reference group, and this exposure explains a substantial fraction of the inverse relation between asthma and growing up on a farm. (Funded by the Deutsche Forschungsgemeinschaft and the European Commission.).  
  Call Number Serial 1983  
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Author (up) Gajer, P.; Brotman, R.M.; Bai, G.; Sakamoto, J.; Schutte, U.M.E.; Zhong, X.; Koenig, S.S.K.; Fu, L.; Ma, Z.S.; Zhou, X.; Abdo, Z.; Forney, L.J.; Ravel, J. file  url
  Title Temporal dynamics of the human vaginal microbiota Type Journal Article
  Year 2012 Publication Science Translational Medicine Abbreviated Journal Sci Transl Med  
  Volume 4 Issue 132 Pages 132ra52  
  Keywords Bacteria/classification/genetics; Female; Humans; Magnetic Resonance Spectroscopy; Metabolome; Metabolomics; Metagenome/genetics/*physiology; Models, Biological; Phylogeny; Time Factors; Vagina/*microbiology; Microbiome  
  Abstract Elucidating the factors that impinge on the stability of bacterial communities in the vagina may help in predicting the risk of diseases that affect women's health. Here, we describe the temporal dynamics of the composition of vaginal bacterial communities in 32 reproductive-age women over a 16-week period. The analysis revealed the dynamics of five major classes of bacterial communities and showed that some communities change markedly over short time periods, whereas others are relatively stable. Modeling community stability using new quantitative measures indicates that deviation from stability correlates with time in the menstrual cycle, bacterial community composition, and sexual activity. The women studied are healthy; thus, it appears that neither variation in community composition per se nor higher levels of observed diversity (co-dominance) are necessarily indicative of dysbiosis.  
  Call Number Serial 2175  
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Author (up) Gohir, W.; Ratcliffe, E.M.; Sloboda, D.M. file  url
  Title Of the bugs that shape us: maternal obesity, the gut microbiome, and long-term disease risk Type Journal Article
  Year 2015 Publication Pediatric Research Abbreviated Journal Pediatr Res  
  Volume 77 Issue 1-2 Pages 196-204  
  Keywords Female; Gastrointestinal Tract/growth & development/*microbiology; Humans; *Maternal Nutritional Physiological Phenomena; *Maternal-Fetal Exchange; *Microbiota; Obesity/*complications/microbiology; Pregnancy; Prenatal Exposure Delayed Effects/immunology/*microbiology; Microbiome  
  Abstract Chronic disease risk is inextricably linked to our early-life environment, where maternal, fetal, and childhood factors predict disease risk later in life. Currently, maternal obesity is a key predictor of childhood obesity and metabolic complications in adulthood. Although the mechanisms are unclear, new and emerging evidence points to our microbiome, where the bacterial composition of the gut modulates the weight gain and altered metabolism that drives obesity. Over the course of pregnancy, maternal bacterial load increases, and gut bacterial diversity changes and is influenced by pre-pregnancy- and pregnancy-related obesity. Alterations in the bacterial composition of the mother have been shown to affect the development and function of the gastrointestinal tract of her offspring. How these microbial shifts influence the maternal-fetal-infant relationship is a topic of hot debate. This paper will review the evidence linking nutrition, maternal obesity, the maternal gut microbiome, and fetal gut development, bringing together clinical observations in humans and experimental data from targeted animal models.  
  Call Number Serial 2080  
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Author (up) Kramer, A.; Bekeschus, S.; Bröker, B.M.; Schleibinger, H.; Razavi, B.; Assadian, O. file  url
  Title Maintaining health by balancing microbial exposure and prevention of infection: the hygiene hypothesis versus the hypothesis of early immune challenge Type Journal Article
  Year 2013 Publication Journal of Hospital Infection Abbreviated Journal Journal of Hospital Infection  
  Volume 83 Issue Pages S29-S34  
  Keywords Early immune challenge hypothesis; Household hygiene; Hygiene hypothesis; Immune System; Lifestyle; Microbiome  
  Abstract The human immune system is inseparably bonded to an individual's personal micro-biome from birth to death. Since the beginning of life, commensal relationships have ensured the survival of micro- and macro-organisms within complex relationships. However, technological advances and altered lifestyle imposed new rules for this interaction during recent decades. It has been observed that reduced exposure to micro-organisms and parasites results in decreased morbidity and mortality, but is also associated with a rising prevalence of atopic disorders and autoimmune diseases, mostly in industrialized countries. This inverse relationship is described by the “hygiene hypothesis”, put forward in 1989, yet this term only imperfectly describes these observations, as excessive hygiene or hygienic measures may not directly be the central cause. The lack of appropriate immune stimulation during early childhood with the consequence of disturbed alignment in the sequence of encountering self- or non-self-antigens might account in the rise of atopy and autoimmune disease. For this reason we propose the term “early immune challenge hypothesis”. This concept highlights the importance of immune priming in early life in the context of genetic, social, geographic, cultural, and economic background. Moreover, it emphasizes the central role of “training” of regulatory T-cells through sufficient microbial exposure, leading to a robust, healthy balance between inflammation and anti-inflammation or immune tolerance. Insufficient exposure might result in abnormal immune regulatory development. Finally, it incorporates the idea of encountering “old friends”--organisms that shaped our immune system during human phylogeny. This article gives a comprehensive overview of the relationship between microbial exposure, and the incidence of asthma and hay fever is outlined. Although the outcomes of these studies originally were interpreted in the framework of the hygiene hypothesis, they may suit the concept of the hypothesis of early immune challenge even better. Moreover, recent studies have revealed that TH or TReg imbalances in disease may be partially corrected by the administration of helminthic or bacterial extracts.  
  Call Number Serial 2099  
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