[Preoperatiove Airway Bacterial Colonization: the Missing Link between Non-small Cell Lung Cancer Following Lobectomy and Postoperative Pneumonia?

PubMed

Gao, Ke; Lai, Yutian; Huang, Jian; Wang, Yifan; Wang, Xiaowei; Che, Guowei

2017-04-20

Surgical procedure is the main method of treating lung cancer. Meanwhile, postoperative pneumonia (POP) is the major cause of perioperative mortality in lung cancer surgery. The preoperative pathogenic airway bacterial colonization is an independent risk factor causing postoperative pulmonary complications (PPC). This cross-sectional study aimed to explore the relationship between preoperative pathogenic airway bacterial colonization and POP in lung cancer and to identify the high-risk factors of preoperative pathogenic airway bacterial colonization. A total of 125 patients with non-small cell lung cancer (NSCLC) underwent thoracic surgery in six hospitals of Chengdu between May 2015 and January 2016. Preoperative pathogenic airway bacterial colonization was detected in all patients via fiber bronchoscopy. Patients' PPC, high-risk factors, clinical characteristics, and the serum surfactant protein D (SP-D) level were also analyzed. The incidence of preoperative pathogenic airway bacterial colonization among NSCLC patients was 15.2% (19/125). Up to 22 strains were identified in the colonization positive group, with Gram-negative bacteria being dominant (86.36%, 19/22). High-risk factors of pathogenic airway bacterial colonization were age (≥75 yr) and smoking index (≥400 cigarettes/year). PPC incidence was significantly higher in the colonization-positive group (42.11%, 8/19) than that in the colonization-negative group (16.04%, 17/106)(P=0.021). POP incidence was significantly higher in the colonization-positive group (26.32%, 5/19) than that in the colonization-negative group (6.60%, 7/106)(P=0.019). The serum SP-D level of patients in the colonization-positive group was remarkably higher than that in the colonization-negative group [(31.25±6.09) vs (28.17±5.23)](P=0.023). The incidence of preoperative pathogenic airway bacterial colonization among NSCLC patients with POP was 41.67% (5/12). This value was 3.4 times higher than that among the patients without

Identification of Population Bottlenecks and Colonization Factors during Assembly of Bacterial Communities within the Zebrafish Intestine

PubMed Central

Wiles, Travis J.; Martinez, Emily S.; Jemielita, Matthew; Burns, Adam R.; Parthasarathy, Raghuveer; Bohannan, Brendan J. M.

2015-01-01

ABSTRACT The zebrafish, Danio rerio, is a powerful model for studying bacterial colonization of the vertebrate intestine, but the genes required by commensal bacteria to colonize the zebrafish gut have not yet been interrogated on a genome-wide level. Here we apply a high-throughput transposon mutagenesis screen to Aeromonas veronii Hm21 and Vibrio sp. strain ZWU0020 during their colonization of the zebrafish intestine alone and in competition with each other, as well as in different colonization orders. We use these transposon-tagged libraries to track bacterial population sizes in different colonization regimes and to identify gene functions required during these processes. We show that intraspecific, but not interspecific, competition with a previously established bacterial population greatly reduces the ability of these two bacterial species to colonize. Further, using a simple binomial sampling model, we show that under conditions of interspecific competition, genes required for colonization cannot be identified because of the population bottleneck experienced by the second colonizer. When bacteria colonize the intestine alone or at the same time as the other species, we find shared suites of functional requirements for colonization by the two species, including a prominent role for chemotaxis and motility, regardless of the presence of another species. PMID:26507229

Bacterial α2-macroglobulins: colonization factors acquired by horizontal gene transfer from the metazoan genome?

PubMed Central

Budd, Aidan; Blandin, Stephanie; Levashina, Elena A; Gibson, Toby J

2004-01-01

Background Invasive bacteria are known to have captured and adapted eukaryotic host genes. They also readily acquire colonizing genes from other bacteria by horizontal gene transfer. Closely related species such as Helicobacter pylori and Helicobacter hepaticus, which exploit different host tissues, share almost none of their colonization genes. The protease inhibitor α2-macroglobulin provides a major metazoan defense against invasive bacteria, trapping attacking proteases required by parasites for successful invasion. Results Database searches with metazoan α2-macroglobulin sequences revealed homologous sequences in bacterial proteomes. The bacterial α2-macroglobulin phylogenetic distribution is patchy and violates the vertical descent model. Bacterial α2-macroglobulin genes are found in diverse clades, including purple bacteria (proteobacteria), fusobacteria, spirochetes, bacteroidetes, deinococcids, cyanobacteria, planctomycetes and thermotogae. Most bacterial species with bacterial α2-macroglobulin genes exploit higher eukaryotes (multicellular plants and animals) as hosts. Both pathogenically invasive and saprophytically colonizing species possess bacterial α2-macroglobulins, indicating that bacterial α2-macroglobulin is a colonization rather than a virulence factor. Conclusions Metazoan α2-macroglobulins inhibit proteases of pathogens. The bacterial homologs may function in reverse to block host antimicrobial defenses. α2-macroglobulin was probably acquired one or more times from metazoan hosts and has then spread widely through other colonizing bacterial species by more than 10 independent horizontal gene transfers. yfhM-like bacterial α2-macroglobulin genes are often found tightly linked with pbpC, encoding an atypical peptidoglycan transglycosylase, PBP1C, that does not function in vegetative peptidoglycan synthesis. We suggest that YfhM and PBP1C are coupled together as a periplasmic defense and repair system. Bacterial α2-macroglobulins might

The quest for a unified view of bacterial land colonization

PubMed Central

Wu, Hao; Fang, Yongjun; Yu, Jun; Zhang, Zhang

2014-01-01

Exploring molecular mechanisms underlying bacterial water-to-land transition represents a critical start toward a better understanding of the functioning and stability of the terrestrial ecosystems. Here, we perform comprehensive analyses based on a large variety of bacteria by integrating taxonomic, phylogenetic and metagenomic data, in the quest for a unified view that elucidates genomic, evolutionary and ecological dynamics of the marine progenitors in adapting to nonaquatic environments. We hypothesize that bacterial land colonization is dominated by a single-gene sweep, that is, the emergence of dnaE2 derived from an early duplication event of the primordial dnaE, followed by a series of niche-specific genomic adaptations, including GC content increase, intensive horizontal gene transfer and constant genome expansion. In addition, early bacterial radiation may be stimulated by an explosion of land-borne hosts (for example, plants and animals) after initial land colonization events. PMID:24451209

Secreted mucins and airway bacterial colonization in non-CF bronchiectasis.

PubMed

Sibila, Oriol; Suarez-Cuartin, Guillermo; Rodrigo-Troyano, Ana; Fardon, Thomas C; Finch, Simon; Mateus, Eder Freddy; Garcia-Bellmunt, Laia; Castillo, Diego; Vidal, Silvia; Sanchez-Reus, Ferran; Restrepo, Marcos I; Chalmers, James D

2015-10-01

Secreted mucins play a key role in antibacterial defence in the airway, but have not previously been characterized in non-cystic fibrosis (CF) bronchiectasis patients. We aim to investigate the relationship between secreted mucins levels and the presence of bacterial colonization due to potentially pathogenic microorganisms (PPM) in the airways of stable bronchiectasis patients. Clinically stable bronchiectasis patients were studied prospectively at two centres. Patients with other pulmonary conditions were excluded. Spontaneous sputum was subject to bacterial culture, and secreted mucins (MUC2, MUC5AC and MUC5B) were measured in sputum supernatants by ELISA. A total of 50 patients were included. PPM were identified from sputum samples in 30 (60%), with Pseudomonas aeruginosa (n = 10) and Haemophilus influenzae (n = 10) as the most common PPM. There were no baseline differences among airway colonized and non-colonized patients. Patients with airways colonized by PPM presented higher levels of airway MUC2. No differences in MUC5AC levels were found among groups, whereas MUC5B levels were undetectable. Patients with P. aeruginosa colonization expressed the highest levels of MUC2. High levels of MUC2 and MUC5AC are also correlated with disease severity using the Bronchiectasis Severity Index. Airway MUC2 levels were higher in bronchiectasis patients colonized with PPM compared with those without airway colonization, especially in patients with P. aeruginosa. These findings suggest that airway-secreted mucins levels may play a role in the pathogenesis of airway infection in non-CF bronchiectasis. © 2015 Asian Pacific Society of Respirology.

Different cytokine response of primary colonic epithelial cells to commensal bacteria.

PubMed

Lan, Jing-Gang; Cruickshank, Sheena-Margaret; Singh, Joy-Carmelina-Indira; Farrar, Mark; Lodge, James-Peter-Alan; Felsburg, Peter-John; Carding, Simon-Richard

2005-06-14

To determine if primary murine colonic epithelial cells (CEC) respond to commensal bacteria and discriminate between different types of bacteria. A novel CEC: bacteria co-culture system was used to compare the ability of the colonic commensal bacteria, Bacteroides ovatus, E. coli (SLF) and Lactobacillus rhamnosus (LGG) to modulate production of different cytokines (n = 15) by primary CEC. Antibody staining and flow cytometry were used to investigate Toll-like receptor (TLR) expression by CEC directly ex vivo and TLR responsiveness was determined by examining the ability of TLR ligands to influence CEC cytokine production. Primary CEC constitutively expressed functional TLR2 and TLR4. Cultured in complete medium alone, CEC secreted IL-6, MCP-1 and IP-10 the levels of which were significantly increased upon addition of the TLR ligands peptidoglycan (PGN) and lipopolysaccharide (LPS). Exposure to the commensal bacteria induced or up-regulated different patterns of cytokine production and secretion. E. coli induced production of MIP-1alpha/beta and betadefensin3 whereas B. ovatus and L. rhamnosus exclusively induced MCP-1 and MIP-2alpha expression, respectively. TNFalpha, RANTES and MEC were induced or up-regulated in response to some but not all of the bacteria whereas ENA78 and IP-10 were up-regulated in response to all bacteria. Evidence of bacterial interference and suppression of cytokine production was obtained from mixed bacterial: CEC co-cultures. Probiotic LGG suppressed E. coli- and B. ovatus-induced cytokine mRNA accumulation and protein secretion. These observations demonstrate the ability of primary CEC to respond to and discriminate between different strains of commensal bacteria and identify a mechanism by which probiotic bacteria (LGG) may exert anti-inflammatory effects in vivo.

Different cytokine response of primary colonic epithelial cells to commensal bacteria

PubMed Central

Lan, Jing-Gang; Cruickshank, Sheena Margaret; Singh, Joy Carmelina Indira; Farrar, Mark; Lodge, James Peter Alan; Felsburg, Peter John; Carding, Simon Richard

2005-01-01

AIM: To determine if primary murine colonic epithelial cells (CEC) respond to commensal bacteria and discriminate between different types of bacteria. METHODS: A novel CEC: bacteria co-culture system was used to compare the ability of the colonic commensal bacteria, Bacteroides ovatus, E. coli (SLF) and Lactobacillus rhamnosus (LGG) to modulate production of different cytokines (n = 15) by primary CEC. Antibody staining and flow cytometry were used to investigate Toll-like receptor (TLR) expression by CEC directly ex vivo and TLR responsiveness was determined by examining the ability of TLR ligands to influence CEC cytokine production. RESULTS: Primary CEC constitutively expressed functional TLR2 and TLR4. Cultured in complete medium alone, CEC secreted IL-6, MCP-1 and IP-10 the levels of which were significantly increased upon addition of the TLR ligands peptidoglycan (PGN) and lipopolysaccharide (LPS). Exposure to the commensal bacteria induced or up-regulated different patterns of cytokine production and secretion. E. coli induced production of MIP-1α/β and β defensin3 whereas B. ovatus and L. rhamnosus exclusively induced MCP-1 and MIP-2α expression, respectively. TNFα, RANTES and MEC were induced or up-regulated in response to some but not all of the bacteria whereas ENA78 and IP-10 were up-regulated in response to all bacteria. Evidence of bacterial interference and suppression of cytokine production was obtained from mixed bacterial: CEC co-cultures. Probiotic LGG suppressed E. coli- and B. ovatus-induced cytokine mRNA accumulation and protein secretion. CONCLUSION: These observations demonstrate the ability of primary CEC to respond to and discriminate between different strains of commensal bacteria and identify a mechanism by which probiotic bacteria (LGG) may exert anti-inflammatory effects in vivo. PMID:15948242

Flow Chamber System for the Statistical Evaluation of Bacterial Colonization on Materials

PubMed Central

Menzel, Friederike; Conradi, Bianca; Rodenacker, Karsten; Gorbushina, Anna A.; Schwibbert, Karin

2016-01-01

Biofilm formation on materials leads to high costs in industrial processes, as well as in medical applications. This fact has stimulated interest in the development of new materials with improved surfaces to reduce bacterial colonization. Standardized tests relying on statistical evidence are indispensable to evaluate the quality and safety of these new materials. We describe here a flow chamber system for biofilm cultivation under controlled conditions with a total capacity for testing up to 32 samples in parallel. In order to quantify the surface colonization, bacterial cells were DAPI (4`,6-diamidino-2-phenylindole)-stained and examined with epifluorescence microscopy. More than 100 images of each sample were automatically taken and the surface coverage was estimated using the free open source software g’mic, followed by a precise statistical evaluation. Overview images of all gathered pictures were generated to dissect the colonization characteristics of the selected model organism Escherichia coli W3310 on different materials (glass and implant steel). With our approach, differences in bacterial colonization on different materials can be quantified in a statistically validated manner. This reliable test procedure will support the design of improved materials for medical, industrial, and environmental (subaquatic or subaerial) applications. PMID:28773891

Bacterial filamentation accelerates colonization of adhesive spots embedded in biopassive surfaces

NASA Astrophysics Data System (ADS)

Möller, Jens; Emge, Philippe; Avalos Vizcarra, Ima; Kollmannsberger, Philip; Vogel, Viola

2013-12-01

Sessile bacteria adhere to engineered surfaces and host tissues and pose a substantial clinical and economical risk when growing into biofilms. Most engineered and biological interfaces are of chemically heterogeneous nature and provide adhesive islands for bacterial attachment and growth. To mimic either defects in a surface coating of biomedical implants or heterogeneities within mucosal layers (Peyer's patches), we embedded micrometre-sized adhesive islands in a poly(ethylene glycol) biopassive background. We show experimentally and computationally that filamentation of Escherichia coli can significantly accelerate the bacterial surface colonization under physiological flow conditions. Filamentation can thus provide an advantage to a bacterial population to bridge non-adhesive distances exceeding 5 μm. Bacterial filamentation, caused by blocking of bacterial division, is common among bacterial species and can be triggered by environmental conditions or antibiotic treatment. While great awareness exists that the build-up of antibiotic resistance serves as intrinsic survival strategy, we show here that antibiotic treatment can actually promote surface colonization by triggering filamentation, which in turn prevents daughter cells from being washed away. Our combined microfabrication and computational approaches provide quantitative insights into mechanisms that enable biofouling of biopassive surfaces with embedded adhesive spots, even for spot distances that are multiples of the bacterial length.

Molecular characterization of total and metabolically active bacterial communities of "white colonizations" in the Altamira Cave, Spain.

PubMed

Portillo, M Carmen; Saiz-Jimenez, Cesareo; Gonzalez, Juan M

2009-01-01

Caves with paleolithic paintings are influenced by bacterial development. Altamira Cave (Spain) contains some of the most famous paintings from the Paleolithic era. An assessment of the composition of bacterial communities that have colonized this cave represents a first step in understanding and potentially controlling their proliferation. In this study, areas showing colonization with uncolored microorganisms, referred to as "white colonizations", were analyzed. Microorganisms present in these colonizations were studied using DNA analysis, and those showing significant metabolic activity were detected in RNA-based RNA analysis. Bacterial community fingerprints were obtained both from DNA and RNA analyses, indicating differences between the microorganisms present and metabolically active in these white colonizations. Metabolically active microorganisms represented only a fraction of the total bacterial community present in the colonizations. 16S rRNA gene libraries were used to identify the major representative members of the studied communities. Proteobacteria constituted the most frequently found division both among metabolically active microorganisms (from RNA-based analysis) and those present in the community (from DNA analysis). Results suggest the existence of a huge variety of taxa in white colonizations of the Altamira Cave which represent a potential risk for the conservation of the cave and its paintings.

Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

PubMed

Xu, Qingfu; Wischmeyer, Jareth; Gonzalez, Eduardo; Pichichero, Michael E

2017-07-01

We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Outcomes of primary repair and primary anastomosis in war-related colon injuries.

PubMed

Vertrees, Amy; Wakefield, Matthew; Pickett, Chris; Greer, Lauren; Wilson, Abralena; Gillern, Sue; Nelson, Jeffery; Aydelotte, Jayson; Stojadinovic, Alexander; Shriver, Craig

2009-05-01

The role of primary repair (PR) of modern day war-related colon injuries remains controversial. Retrospective review of medical records of combat-wounded soldiers with colon injuries sustained during March 2003 to August 2006 was conducted. Injuries were analyzed according to location: right (n = 30), transverse (n = 13), and left (n = 24) sided colon injuries. Two-tailed Fisher's Exact or chi tests were used for statistical analysis. Seventy-seven soldiers returned to Walter Reed Army Medical Center with colon injuries suffered during Operations Enduring Freedom and Iraqi Freedom. Twelve patients with minor colon injuries were excluded. The remaining 65 patients (mean age, 28 +/- 7 years) sustained 67 colon injuries from secondary blast (n = 38); gunshot (n = 27); motor vehicle crash (n = 1) and crush injury (n = 1). Patients arrived at Walter Reed Army Medical Center 5 days (range, 2-16 days) after injury and damage control operations (n = 27, 42%), and were hospitalized for a median of 22 days (range, 1-306 days). Follow-up averaged 311 days (median, 198 days). PR was attempted in right (n = 18, 60%), transverse (n = 11, 85%), and left (n = 9, 38%) sided colon injuries. Delayed definitive treatment of colon injuries occurred in 42% of patients. Failure of repair occurred in 16% of patients and was more likely with concomitant pancreatic, stomach, splenic, diaphragm, and renal injuries. Overall morbidity for ostomy closure after primary ostomy formation was 30%, but increased to 75% for ostomy closure after primary anastomotic or repair failure. PR of war-related colon injuries can be performed safely in selected circumstances in the absence of concomitant organ injury. Delayed anastomosis can often be performed after damage control operations once the patient stabilizes. Ostomy closure complications are more likely after anastomotic failure.

Gauze Impregnated With Quaternary Ammonium Salt Reduces Bacterial Colonization of Surgical Drains After Breast Reconstruction.

PubMed

Strong, Amy L; Wolfe, Emily T; Shank, Nina; Chaffin, Abigail E; Jansen, David A

2018-06-01

Surgical site infection after breast reconstruction is associated with increased length of hospital stay, readmission rates, cost, morbidity, and mortality. Identifying methods to reduce surgical site infection without the use of antibiotics may be beneficial at reducing antimicrobial resistance, reserving the use of antibiotics for more severe cases. Quaternary ammonium salts have previously been shown to be a safe and effective antimicrobial agent in the setting of in vitro and in vivo animal experiments. A retrospective study was conducted to investigate the antimicrobial properties of a quaternary ammonium salt, 3-trimethoxysilyl propyldimethyloctadecyl ammonium chloride (QAS-3PAC; Bio-spear), at reducing surgical drain site colonization and infection after breast reconstruction (deep inferior epigastric perforator flap reconstruction or tissue expander placement). Twenty patients were enrolled, with 14 surgical drains covered with nonimpregnated gauze and 17 surgical drains covered with QAS-3PAC impregnated gauze, for the purposes of investigating bacterial colonization. Antibiotic sensitivity analysis was also conducted when bacterial cultures were positive. The overall incidence of bacterial colonization of surgical drains was lower in the treatment group compared with the control group (17.6% vs 64.3%, respectively; P = 0.008). QAS-3PAC impregnated gauze reduced the incidence of bacterial colonization of surgical drains during the first (0.0% vs 33.3%) and second (33.3% vs 87.5%; P = 0.04) postoperative week. Furthermore, no enhanced antibiotic resistance was noted on drains treated with QAS-3PAC impregnated gauze. The results of this study suggest that QAS-3PAC impregnated gauze applied over surgical drains may be an effective method for reducing the incidence of bacterial colonization.

Primary T-cell Lymphoma of the Colon

PubMed Central

Son, Hee Jung; Rhee, Poong Lyul; Kim, Jae-Jun; Koh, Kwang Choel; Paik, Seong Woon; Rhee, Jong Chul; Koh, Young Hae

1997-01-01

A 40-year-old woman had been diagnosed with Crohns disease in September 1994, but later examinations revealed a primary T-cell lymphoma of the colon. Colonoscopic and histological examination showed ulcerative lesions simulating Crohns disease involving the entire colon and the terminal ileum, and she was first diagnosed as having Crohns disease. Differential therapeutic strategies, including corticosteroid, had improved the symptoms which were dominated by abdominal pain. When she visited our institute in April 1995, she presented with bloody stool twice a day, 7kg weight loss in a period of six months and a slightly painful abdomen. Colonoscopic finding showed geographic ulceration on the entire colon, especially rectum and terminal ileum. The histologic examination of specimens from colonoscopic biopsy showed primary peripheral T-cell lymphoma of the colon. Any dense lymphocyte infiltrates seen in the biopsy specimens obtained from lesions simulating ulcerative colitis or Crohns disease should be assessed to exclude intestinal lymphoma PMID:9439161

Biocontrol of Bacterial Fruit Blotch by Bacillus subtilis 9407 via Surfactin-Mediated Antibacterial Activity and Colonization.

PubMed

Fan, Haiyan; Zhang, Zhanwei; Li, Yan; Zhang, Xun; Duan, Yongming; Wang, Qi

2017-01-01

In this study, Bacillus subtilis 9407 showed a strong antibacterial activity against Acidovorax citrulli in vitro and 61.7% biocontrol efficacy on melon seedlings 4 days post inoculation under greenhouse conditions. To understand the biocontrol mechanism of B. subtilis 9407, identify the primary antibacterial compound and determine its role in controlling bacterial fruit blotch (BFB), a srfAB deletion mutant (Δ srfAB ) was constructed. The Δ srfAB which was deficient in production of surfactin, not only showed almost no ability to inhibit growth of A. citrulli but also decreased biofilm formation and reduced swarming motility. Colonization assay demonstrated that B. subtilis 9407 could conlonize on melon roots and leaves in a large population, while Δ srfAB showed a four- to ten-fold reduction in colonization of melon roots and leaves. Furthermore, a biocontrol assay showed that Δ srfAB lost the biocontrol efficacy. In summary, our results indicated that surfactin, which consists of C13- to C16-surfactin A was the primary antibacterial compound of B. subtilis 9407, and it played a major role in biofilm formation, swarming motility, colonization and suppressing BFB. We propose that the biocontrol activity of B. subtilis 9407 is the results of the coordinated action of surfactin-mediated antibacterial activity and colonization. This study reveals for the first time that the use of a B. subtilis strain as a potential biological control agent could efficiently control BFB by producing surfactin.

Biocontrol of Bacterial Fruit Blotch by Bacillus subtilis 9407 via Surfactin-Mediated Antibacterial Activity and Colonization

PubMed Central

Fan, Haiyan; Zhang, Zhanwei; Li, Yan; Zhang, Xun; Duan, Yongming; Wang, Qi

2017-01-01

In this study, Bacillus subtilis 9407 showed a strong antibacterial activity against Acidovorax citrulli in vitro and 61.7% biocontrol efficacy on melon seedlings 4 days post inoculation under greenhouse conditions. To understand the biocontrol mechanism of B. subtilis 9407, identify the primary antibacterial compound and determine its role in controlling bacterial fruit blotch (BFB), a srfAB deletion mutant (ΔsrfAB) was constructed. The ΔsrfAB which was deficient in production of surfactin, not only showed almost no ability to inhibit growth of A. citrulli but also decreased biofilm formation and reduced swarming motility. Colonization assay demonstrated that B. subtilis 9407 could conlonize on melon roots and leaves in a large population, while ΔsrfAB showed a four- to ten-fold reduction in colonization of melon roots and leaves. Furthermore, a biocontrol assay showed that ΔsrfAB lost the biocontrol efficacy. In summary, our results indicated that surfactin, which consists of C13- to C16-surfactin A was the primary antibacterial compound of B. subtilis 9407, and it played a major role in biofilm formation, swarming motility, colonization and suppressing BFB. We propose that the biocontrol activity of B. subtilis 9407 is the results of the coordinated action of surfactin-mediated antibacterial activity and colonization. This study reveals for the first time that the use of a B. subtilis strain as a potential biological control agent could efficiently control BFB by producing surfactin. PMID:29075242

Prevention of bacterial colonization of contact lenses with covalently attached selenium and effects on the rabbit cornea.

PubMed

Mathews, Steven M; Spallholz, Julian E; Grimson, Mark J; Dubielzig, Richard R; Gray, Tracy; Reid, Ted W

2006-08-01

Although silicone hydrogel materials have produced many corneal health benefits to patients wearing contact lenses, bacteria that cause acute red eye or corneal ulcers are still a concern. A coating that inhibits bacterial colonization while not adversely affecting the cornea should improve the safety of contact lens wear. A covalent selenium (Se) coating on contact lenses was evaluated for safety using rabbits and prevention of bacterial colonization of the contact lenses in vitro. Contact lenses coated with Se were worn on an extended-wear schedule for up to 2 months by 10 New Zealand White rabbits. Corneal health was evaluated with slit-lamp biomicroscopy, pachymetry, electron microscopy, and histology. Lenses worn by the rabbits were analyzed for protein and lipid deposits. In addition, the ability of Se to block bacterial colonization was tested in vitro by incubating lenses in a Pseudomonas aeruginosa broth followed by scanning electron microscopy of the contact lens surface. The covalent Se coating decreased bacterial colonization in vitro while not adversely affecting the corneal health of rabbits in vivo. The Se coating produced no noticeable negative effects as observed with slit-lamp biomicroscopy, pachymetry, electron microscopy, and histology. The Se coating did not affect protein or lipid deposition on the contact lenses. The data from this pilot study suggest that a Se coating on contact lenses might reduce acute red eye and bacterial ulceration because of an inhibition of bacterial colonization. In addition, our safety tests suggest that this positive effect can be produced without an adverse effect on corneal health.

Probiotic E. coli Nissle 1917 biofilms on silicone substrates for bacterial interference against pathogen colonization.

PubMed

Chen, Quan; Zhu, Zhiling; Wang, Jun; Lopez, Analette I; Li, Siheng; Kumar, Amit; Yu, Fei; Chen, Haoqing; Cai, Chengzhi; Zhang, Lijuan

2017-03-01

Bacterial interference is an alternative strategy to fight against device-associated bacterial infections. Pursuing this strategy, a non-pathogenic bacterial biofilm is used as a live, protective barrier to fence off pathogen colonization. In this work, biofilms formed by probiotic Escherichia coli strain Nissle 1917 (EcN) are investigated for their potential for long-term bacterial interference against infections associated with silicone-based urinary catheters and indwelling catheters used in the digestive system, such as feeding tubes and voice prostheses. We have shown that EcN can form stable biofilms on silicone substrates, particularly those modified with a biphenyl mannoside derivative. These biofilms greatly reduced the colonization by pathogenic Enterococcus faecalis in Lysogeny broth (LB) for 11days. Bacterial interference is an alternative strategy to fight against device-associated bacterial infections. Pursuing this strategy, we use non-pathogenic bacteria to form a biofilm that serves as a live, protective barrier against pathogen colonization. Herein, we report the first use of preformed probiotic E. coli Nissle 1917 biofilms on the mannoside-presenting silicone substrates to prevent pathogen colonization. The biofilms serve as a live, protective barrier to fence off the pathogens, whereas current antimicrobial/antifouling coatings are subjected to gradual coverage by the biomass from the rapidly growing pathogens in a high-nutrient environment. It should be noted that E. coli Nissle 1917 is commercially available and has been used in many clinical trials. We also demonstrated that this probiotic strain performed significantly better than the non-commercial, genetically modified E. coli strain that we previously reported. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Predicting postoperative fever and bacterial colonization on packing material following endoscopic endonasal surgery.

PubMed

Nomura, Kazuhiro; Yamanaka, Yurika; Sekine, Yasuhiro; Yamamoto, Hiroki; Esu, Yoshihiko; Hara, Mariko; Hasegawa, Masayo; Shinnabe, Akihiro; Kanazawa, Hiromi; Kakuta, Risako; Ozawa, Daiki; Hidaka, Hiroshi; Katori, Yukio; Yoshida, Naohiro

2017-01-01

Postoperative fever following endoscopic endonasal surgery is a rare occurrence of concern to surgeons. To elucidate preoperative and operative predictors of postoperative fever, we analyzed the characteristics of patients and their perioperative background in association with postoperative fever. A retrospective review of 371 patients who had undergone endoscopic endonasal surgery was conducted. Predictors, including intake of antibiotics, steroids, history of asthma, preoperative nasal bacterial culture, duration of operation, duration of packing and intraoperative intravenous antibiotics on the occurrence of postoperative fever, and bacterial colonization on the packing material, were analyzed retrospectively. Fever (≥38 °C) occurred in 63 (17 %) patients. Most incidences of fever occurred on postoperative day one. In majority of these cases, the fever subsided after removal of the packing material without further antibiotic administration. However, one patient who experienced persistent fever after the removal of packing material developed meningitis. History of asthma, prolonged operation time (≥108 min), and intravenous cefazolin administration instead of cefmetazole were associated with postoperative fever. Odds ratios (ORs) for each were 2.3, 4.6, and 2.0, respectively. Positive preoperative bacterial colonization was associated with postoperative bacterial colonization on the packing material (OR 2.3). Postoperative fever subsided in most patients after removal of the packing material. When this postoperative fever persists, its underlying cause should be examined.

Dermacentor andersoni transmission of Francisella tularensis subsp. novicida reflects bacterial colonization, dissemination and replication coordinated with tick feeding.

USDA-ARS?s Scientific Manuscript database

Ticks serve as biological vectors for a wide variety of bacterial pathogens which must be able to efficiently colonize specific tick tissues prior to transmission. The bacterial determinants of tick colonization are largely unknown, a knowledge gap attributed in large part to the paucity of tools t...

Proteinaceous determinants of surface colonization in bacteria: bacterial adhesion and biofilm formation from a protein secretion perspective

PubMed Central

Chagnot, Caroline; Zorgani, Mohamed A.; Astruc, Thierry; Desvaux, Mickaël

2013-01-01

Bacterial colonization of biotic or abiotic surfaces results from two quite distinct physiological processes, namely bacterial adhesion and biofilm formation. Broadly speaking, a biofilm is defined as the sessile development of microbial cells. Biofilm formation arises following bacterial adhesion but not all single bacterial cells adhering reversibly or irreversibly engage inexorably into a sessile mode of growth. Among molecular determinants promoting bacterial colonization, surface proteins are the most functionally diverse active components. To be present on the bacterial cell surface, though, a protein must be secreted in the first place. Considering the close association of secreted proteins with their cognate secretion systems, the secretome (which refers both to the secretion systems and their protein substrates) is a key concept to apprehend the protein secretion and related physiological functions. The protein secretion systems are here considered in light of the differences in the cell-envelope architecture between diderm-LPS (archetypal Gram-negative), monoderm (archetypal Gram-positive) and diderm-mycolate (archetypal acid-fast) bacteria. Besides, their cognate secreted proteins engaged in the bacterial colonization process are regarded from single protein to supramolecular protein structure as well as the non-classical protein secretion. This state-of-the-art on the complement of the secretome (the secretion systems and their cognate effectors) involved in the surface colonization process in diderm-LPS and monoderm bacteria paves the way for future research directions in the field. PMID:24133488

Colon trauma: primary repair evolving as the standard of care.

PubMed Central

Muffoletto, J. P.; Tate, J. S.

1996-01-01

This study reviewed the management of colon injuries treated at the trauma surgical service, University of Nevada Medical Center between 1987 and 1992. Sixty-six patients sustained either blunt or penetrating colon injuries during the study period. The patients were divided into two groups: patients who underwent diverting colostomies and patients who underwent primary repair. Both groups were equally matched in terms of colon injury severity as well as trauma scores. The results indicated that primary colon repair was as safe if not safer than colostomy with less complications and at lower costs. The authors conclude that primary repair should be reevaluated in a critical manner as an evolving standard of care. PMID:8855649

Effect of flow and active mixing on bacterial growth in a colon-like geometry

NASA Astrophysics Data System (ADS)

Cremer, Jonas; Segota, Igor; Arnoldini, Markus; Groisman, Alex; Hwa, Terence

The large intestine harbors bacteria from hundreds of species, with bacterial densities reaching up to 1012 cells per gram. Many different factors influence bacterial growth dynamics and thus bacterial density and microbiota composition. One dominant force is flow which can in principle lead to a washout of bacteria from the proximal colon. Active mixing by Contractions of the colonic wall together with bacterial growth might counteract such flow-forces and allow high bacterial densities to occur. As a step towards understanding bacterial growth in the presence of mixing and flow, we constructed an in-vitro setup where controlled wall-deformations of a channel emulate Contractions. We investigate growth along the channel under a steady nutrient inflow. In the limits of no or very frequent Contractions, the device behaves like a plug-flow reactor and a chemostat respectively. Depending on mixing and flow, we observe varying spatial gradients in bacterial density along the channel. Active mixing by deformations of the channel wall is shown to be crucial in maintaining a steady-state bacterial population in the presence of flow. The growth-dynamics is quantitatively captured by a simple mathematical model, with the effect of mixing described by an effective diffusion term.

Primary leiomyosarcoma in the colon

PubMed Central

Yang, Jing

2018-01-01

Abstract Rationale: Leiomyosarcoma (LMS) is a common type of soft tissue sarcoma. Primary colonic LMS in general is a very rare entity, accounting for 1% to 2% of gastrointestinal malignancies. Patient concerns: We report a case of 55-year-old female who presented with a sudden onset of sharp right lower quadrant abdominal pain. Electronic colonoscopy showed a normal lumen. However, an abdominal computed tomography scan revealed a mass of soft tissue attenuation inseparable from the ascending colon which appeared as a gastrointestinal stromal tumor (GIST). Diagnoses: It is important to diagnose LMS definitively by immunohistochemical profiling of smooth muscle actin, desmin, and CD34. Interventions: She underwent laparotomy and right hemicolectomy, and histology confirmed a colonic LMS. The patient received no oncological treatment after surgery. Outcomes: No recurrence or metastasis was observed at 5 months postoperatively. It is crucial to identify colonic LMS precisely based on immunohistochemistry, and thereby distinguish it from GIST. Lessons: Further investigation on LMS cases so far is required to establish standard treatment strategies. PMID:29443772

Bacterial species colonizing the vagina of healthy women are not associated with race.

PubMed

Beamer, May A; Austin, Michele N; Avolia, Hilary A; Meyn, Leslie A; Bunge, Katherine E; Hillier, Sharon L

2017-06-01

The vaginal microbiota of 36 white versus 25 black asymptomatic women were compared using both cultivation-dependent and -independent identification. Significant differences by race were found in colonization and density of bacterial species. However, exclusion of 12 women with bacterial vaginosis by Nugent criteria resulted in no significant differences by race. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Usefulness of Intraoperative Colonic Irrigation and Primary Anastomosis in Patients Requiring a Left Colon Resection.

PubMed

Hong, Youngki; Nam, Soomin; Kang, Jung Gu

2017-06-01

The aim of this study is to assess the short-term outcome of intraoperative colonic irrigation and primary anastomosis and to suggest the usefulness of the procedure when a preoperative mechanical bowel preparation is inappropriate. This retrospective study included 38 consecutive patients (19 male patients) who underwent intraoperative colonic irrigation and primary anastomosis for left colon disease between January 2010 and December 2016. The medical records of the patients were reviewed to evaluate the patients' characteristics, operative data, and postoperative short-term outcomes. Twenty-nine patients had colorectal cancer, 7 patients had perforated diverticulitis, and the remaining 2 patients included 1 with sigmoid volvulus and 1 with a perforated colon due to focal colonic ischemia. A diverting loop ileostomy was created in 4 patients who underwent a low anterior resection. Complications occurred in 15 patients (39.5%), and the majority was superficial surgical site infections (18.4%). Anastomotic leakage occurred in one patient (2.6%) who underwent an anterior resection due sigmoid colon cancer with obstruction. No significant difference in overall postoperative complications and superficial surgical site infections between patients with obstruction and those with peritonitis were noted. No mortality occurred during the first 30 postoperative days. The median hospital stay after surgery was 15 days (range, 8-39 days). Intraoperative colonic irrigation and primary anastomosis seem safe and feasible in selected patients. This procedure may reduce the burden of colostomy in patients requiring a left colon resection with an inappropriate preoperative mechanical bowel preparation.

Colon diversion versus primary colonic repair in gunshot abdomen with penetrating colon injury in Libyan revolution conflict 2011 (a single center experience).

PubMed

Mansor, Salah; Bendardaf, Rashed; Bougrara, Muftah; Hagam, Mohamed

2014-09-01

The objective of this study is comparing colon diversion versus primary repair in penetrating colon gunshot injuries. A retrospective study of 63 cases of gunshot abdomen with penetrating colon injury were admitted to Al-jalla Hospital in 2011 in Benghazi, Libya. After surgical intervention, these patients were observed for any postoperative complications. During the study period, 63 eligible patients included, 62 (98.4%) were males and 1 (1.6%) was female. And the mean age was 29.24 years. Eighteen patients had an injury on the right side of the colon, while 16, 6, 11, 6, 2, 3, and 1 patients had an injury on the transverse, left, sigmoid, rectum, right transverse, left transverse, and total colonic injury, respectively. In the first group, 23 patients (36.5%) was treated with colon diversion, (2 with Hartmann's operation, 21 with loop colostomy). In the second group, 40 patients (63.4 %) was treated with primary repair. Eighteen (28.5%) with right hemicolectomy, 5 (7.9%) with transverse colon resection and anastomosis, and 17 (26.9%) with simple repair. We evaluate the rate of postoperative complication and compare the postoperative morbidity between both groups. In our study, there was no significant statistical difference between types of operations and rate of complications (P = 0.18). We could not see any advantage of the diversion over the primary repair. To reduce risk of the psychological trauma, complications of colostomy, unnecessary repeated hospitalization, decrease of economic cost, and complications of stoma revision operation, we should consider that the primary repair of penetrating colon injuries is an acceptable alternative method of treatment over the colostomy.

Causes for massive bacterial colonization on mucosal membranes during infectious mononucleosis: implications for acute otitis media.

PubMed

Stenfors, Lars-Eric; Bye, Helga-Marie; Räisänen, Simo

2002-09-24

A common complication of virus-induced upper respiratory tract infections is acute otitis media caused by bacterial pathogens. Simultaneously, increased bacterial colonization in the nasopharynx occurs. Our intention in this study was to identify the causes of this increased colonization of bacteria by evaluating their coating with the antibacterial substances lysozyme, lactoferrin and immunoglobulins IgG, S-IgA and IgM and their ability to penetrate epithelial cells during infectious mononucleosis (IM) caused by Epstein-Barr virus. Cellular samples were collected from the oropharynx of 21 patients (16 males, five females; age range 10-21 years) with current IM. An immunocytochemical assay using gold-labelled antiserum to human lysozyme, lactoferrin, IgG, S-IgA and IgM followed by gold particle and epithelial cell tracing in the transmission electron microscope. A significant reduction in bacterial coating with IgG (P<0.05) and S-IgA (P<0.01) was noted, whereas there was a significant increase in coating with lactoferrin (P<0.01) and IgM (P<0.01). No significant change in lysozyme coating of the bacteria was noted, compared with healthy controls. Bacterial penetration into epithelial cells was seen particularly in patients culture-positive for beta-haemolytic streptococci. Reduced bacterial coating with IgG and S-IgA immunoglobulins, combined with bacterial penetration into epithelial cells, may exacerbate the bacterial colonization on oropharyngeal mucosal membranes observed during IM.

Primary repair vs. colostomy in colon injuries.

PubMed

Robles-Castillo, Javier; Murillo-Zolezzi, Adrián; Murakami, Pablo Daniel; Silva-Velasco, Jorge

2009-01-01

Colon trauma is frequent and its prevalence is difficult to establish because of the different factors that intervene in its origin. In Mexico, traumatic colon injuries, albeit stab wounds or gunshot wounds, are on the rise. Our objective was to evaluate the most appropriate management for traumatic colon injuries. We conducted a retrospective study of 178 case files of patients with abdominal trauma and colon lesions during a 5-year period from January 2003 to June 2008 from the General Hospital of Balbuena, Mexico City. The study compared the use of primary closure vs. colostomy, analyzing variables such as sex, age, type of wound, severity of lesion and mortality. There were a total of 178 patients; 156 were male (87.6%) and 22 were female (12.4%). The most affected age group was between 21 and 30 years; 74 patients (41.6%) had stab wounds and 104 patients (58.4%) had gunshot wounds. Management consisted mainly of primary closure in 92 cases (51.7%) vs. colostomy in 86 patients (48.3%). However, 64% of gunshot wounds were treated with colostomy. Reported mortality was 9.55% and this was due to different factors such as multiple organ injury. Treatment of traumatic colon injury should be case specific, taking into account the mechanism of the lesion, its severity and associated injuries.

Bacterial colonization on coated and uncoated orthodontic wires: A prospective clinical trial.

PubMed

Raji, Seyed Hamid; Shojaei, Hasan; Ghorani, Parinaz Saeidi; Rafiei, Elahe

2014-11-01

The advantages of coated orthodontic wires such as esthetic and their effects on reduced friction, corrosion and allergic reaction and the significant consequences of plaque accumulation on oral health encouraged us to assess bacterial colonization on these wires. A total of 18 (9 upper and 9 lower) epoxy resin coated 16 × 22 nickel-titanium wires (Spectra, GAC, USA) and 18 (9 upper and 9 lower) non-coated 16 × 22 nickel-titanium wires (Sentalloy, GAC, USA) with isolated packages were selected and sterilized before application. The samples were divided randomly between upper and lower arches in 18 patients and hence that every patient received one coated and one uncoated wire at the same time. Samples were removed and cut in equal lengths after 3 weeks and placed in phosphate buffered saline buffer. After separation of bacteria in trypsin and ethylenediaminetetraacetic acid solution, the diluted solution was cultured in blood agar and bacterial colony forming units were counted. Finally, the data was analyzed using the paired t-test and the significance was set at 0.05. Mean of bacterial colonization on uncoated wires was more than that of coated wires (P < 0.001). Bacterial plaque accumulation on epoxy resin coated nickel-titanium orthodontic wires is significantly lower than uncoated nickel-titanium wires.

Role of Streptococcus sanguinis sortase A in bacterial colonization.

PubMed

Yamaguchi, Masaya; Terao, Yutaka; Ogawa, Taiji; Takahashi, Toshihito; Hamada, Shigeyuki; Kawabata, Shigetada

2006-10-01

Streptococcus sanguinis, a normal inhabitant of the human oral cavity, has low cariogenicity, though colonization on tooth surfaces by this bacterium initiates aggregation by other oral bacteria and maturation of dental plaque. Additionally, S. sanguinis is frequently isolated from infective endocarditis patients. We investigated the functions of sortase A (SrtA), which cleaves LPXTG-containing proteins and anchors them to the bacterial cell wall, as a possible virulence factor of S. sanguinis. We identified the srtA gene of S. sanguinis by searching a homologous gene of Streptococcus mutans in genome databases. Next, we constructed an srtA-deficient mutant strain of S. sanguinis by insertional inactivation and compared it to the wild type strain. In the case of the mutant strain, some surface proteins could not anchor to the cell wall and were partially released into the culture supernatant. Furthermore, adherence to saliva-coated hydroxyapatite beads and polystyrene plates, as well as adherence to and invasion of human epithelial cells were reduced significantly in the srtA-deficient strain when compared to the wild type. In addition, antiopsonization levels and bacterial survival of the srtA-deficient mutant were decreased in human whole blood. This is the first known study to report that SrtA contributes to antiopsonization in streptococci. Our results suggest that SrtA anchors surface adhesins as well as some proteins that function as antiopsonic molecules as a means of evading the human immune system. Furthermore, they demonstrate that SrtA of S. sanguinis plays important roles in bacterial colonization.

The Usefulness of Intraoperative Colonic Irrigation and Primary Anastomosis in Patients Requiring a Left Colon Resection

PubMed Central

Hong, Youngki; Nam, Soomin

2017-01-01

Purpose The aim of this study is to assess the short-term outcome of intraoperative colonic irrigation and primary anastomosis and to suggest the usefulness of the procedure when a preoperative mechanical bowel preparation is inappropriate. Methods This retrospective study included 38 consecutive patients (19 male patients) who underwent intraoperative colonic irrigation and primary anastomosis for left colon disease between January 2010 and December 2016. The medical records of the patients were reviewed to evaluate the patients' characteristics, operative data, and postoperative short-term outcomes. Results Twenty-nine patients had colorectal cancer, 7 patients had perforated diverticulitis, and the remaining 2 patients included 1 with sigmoid volvulus and 1 with a perforated colon due to focal colonic ischemia. A diverting loop ileostomy was created in 4 patients who underwent a low anterior resection. Complications occurred in 15 patients (39.5%), and the majority was superficial surgical site infections (18.4%). Anastomotic leakage occurred in one patient (2.6%) who underwent an anterior resection due sigmoid colon cancer with obstruction. No significant difference in overall postoperative complications and superficial surgical site infections between patients with obstruction and those with peritonitis were noted. No mortality occurred during the first 30 postoperative days. The median hospital stay after surgery was 15 days (range, 8–39 days). Conclusion Intraoperative colonic irrigation and primary anastomosis seem safe and feasible in selected patients. This procedure may reduce the burden of colostomy in patients requiring a left colon resection with an inappropriate preoperative mechanical bowel preparation. PMID:28761871

Bacterial colonization of a fumigated alkaline saline soil.

PubMed

Bello-López, Juan M; Domínguez-Mendoza, Cristina A; de León-Lorenzana, Arit S; Delgado-Balbuena, Laura; Navarro-Noya, Yendi E; Gómez-Acata, Selene; Rodríguez-Valentín, Analine; Ruíz-Valdiviezo, Victor M; Luna-Guido, Marco; Verhulst, Nele; Govaerts, Bram; Dendooven, Luc

2014-07-01

After chloroform fumigating an arable soil, the relative abundance of phylotypes belonging to only two phyla (Actinobacteria and Firmicutes) and two orders [Actinomycetales and Bacillales (mostly Bacillus)] increased in a subsequent aerobic incubation, while it decreased for a wide range of bacterial groups. It remained to be seen if similar bacterial groups were affected when an extreme alkaline saline soil was fumigated. Soil with electrolytic conductivity between 139 and 157 dS m(-1), and pH 10.0 and 10.3 was fumigated and the bacterial community structure determined after 0, 1, 5 and 10 days by analysis of the 16S rRNA gene, while an unfumigated soil served as control. The relative abundance of the Firmicutes increased in the fumigated soil (52.8%) compared to the unfumigated soil (34.2%), while that of the Bacteroidetes decreased from 16.2% in the unfumigated soil to 8.8% in the fumigated soil. Fumigation increased the relative abundance of the genus Bacillus from 14.7% in the unfumigated soil to 25.7%. It was found that phylotypes belonging to the Firmicutes, mostly of the genus Bacillus, were dominant in colonizing the fumigated alkaline saline as found in the arable soil, while the relative abundance of a wide range of bacterial groups decreased.

Colonic bacterial composition in Parkinson's disease.

PubMed

Keshavarzian, Ali; Green, Stefan J; Engen, Phillip A; Voigt, Robin M; Naqib, Ankur; Forsyth, Christopher B; Mutlu, Ece; Shannon, Kathleen M

2015-09-01

We showed that Parkinson's disease (PD) patients have alpha-synuclein (α-Syn) aggregation in their colon with evidence of colonic inflammation. If PD patients have altered colonic microbiota, dysbiosis might be the mechanism of neuroinflammation that leads to α-Syn misfolding and PD pathology. Sixty-six sigmoid mucosal biopsies and 65 fecal samples were collected from 38 PD patients and 34 healthy controls. Mucosal-associated and feces microbiota compositions were characterized using high-throughput ribosomal RNA gene amplicon sequencing. Data were correlated with clinical measures of PD, and a predictive assessment of microbial community functional potential was used to identify microbial functions. The mucosal and fecal microbial community of PD patients was significantly different than control subjects, with the fecal samples showing more marked differences than the sigmoid mucosa. At the taxonomic level of genus, putative, "anti-inflammatory" butyrate-producing bacteria from the genera Blautia, Coprococcus, and Roseburia were significantly more abundant in feces of controls than PD patients. Bacteria from the genus Faecalibacterium were significantly more abundant in the mucosa of controls than PD. Putative, "proinflammatory" Proteobacteria of the genus Ralstonia were significantly more abundant in mucosa of PD than controls. Predictive metagenomics indicated that a large number of genes involved in metabolism were significantly lower in the PD fecal microbiome, whereas genes involved in lipopolysaccharide biosynthesis and type III bacterial secretion systems were significantly higher in PD patients. This report provides evidence that proinflammatory dysbiosis is present in PD patients and could trigger inflammation-induced misfolding of α-Syn and development of PD pathology. © 2015 International Parkinson and Movement Disorder Society.

Intraoperative colonic lavage and primary anastomosis in peritonitis and obstruction.

PubMed

Biondo, S; Jaurrieta, E; Jorba, R; Moreno, P; Farran, L; Borobia, F; Bettonica, C; Poves, I; Ramos, E; Alcobendas, F

1997-02-01

The surgical management of left colonic emergencies has evolved in the past few decades. Recently, there has been increasing interest in resection with primary anastomosis in selected cases. The aim of this study was to evaluate the differences in outcome in patients with peritonitis or obstruction treated by resection, on-table lavage and primary anastomosis of the left colon. Between January 1992 and August 1995, 212 patients underwent emergency operation for a distal colonic lesion: 97 presented with peritonitis, 113 with obstruction and two with other indications. Intraoperative colonic lavage was performed in 37 patients with obstruction and in 24 with an acute intra-abdominal inflammatory process. The postoperative mortality rate was 5 per cent. The incidence of clinical anastomotic leakage was 5 per cent. Wound infection was observed in ten patients (16 per cent), more often in those with peritonitis (P = 0.03). The overall mean(s.d.) hospital stay was 15(9) days. Resection, on-table lavage and primary anastomosis constitute the operation of choice for selected patients with left colonic emergency.

Dynamic switching enables efficient bacterial colonization in flow.

PubMed

Kannan, Anerudh; Yang, Zhenbin; Kim, Minyoung Kevin; Stone, Howard A; Siryaporn, Albert

2018-05-22

Bacteria colonize environments that contain networks of moving fluids, including digestive pathways, blood vasculature in animals, and the xylem and phloem networks in plants. In these flow networks, bacteria form distinct biofilm structures that have an important role in pathogenesis. The physical mechanisms that determine the spatial organization of bacteria in flow are not understood. Here, we show that the bacterium P. aeruginosa colonizes flow networks using a cyclical process that consists of surface attachment, upstream movement, detachment, movement with the bulk flow, and surface reattachment. This process, which we have termed dynamic switching, distributes bacterial subpopulations upstream and downstream in flow through two phases: movement on surfaces and cellular movement via the bulk. The model equations that describe dynamic switching are identical to those that describe dynamic instability, a process that enables microtubules in eukaryotic cells to search space efficiently to capture chromosomes. Our results show that dynamic switching enables bacteria to explore flow networks efficiently, which maximizes dispersal and colonization and establishes the organizational structure of biofilms. A number of eukaryotic and mammalian cells also exhibit movement in two phases in flow, which suggests that dynamic switching is a modality that enables efficient dispersal for a broad range of cell types.

[Timing of bacterial colonization in severe burns: is strict isolation necessary?].

PubMed

Barret, Juan P

2003-12-01

Infection is still one of the main causes of mortality in severe burn patients. Strict isolation has been used for the prevention of infection, but the efficacy of this measure is debatable. The aim of this study was to determine the timing of bacterial colonization in these patients and to ascertain whether strict isolation is indicated. Thirty consecutive children with severe burns were studied. Patients were only barrier-nursed during dressing changes. On admission and twice weekly over the entire hospital stay, burn, sputum, gastric aspirates, feces, and blood samples were obtained for culture. All isolates were tested for specific biotypes. Results were studied with linear regression and repeated measures ANOVA to determine the timing of colonization and cross-colonization between patients. On admission, normal cutaneous flora were isolated from burn cultures of all patients. The remaining cultures were negative. After one week, gastric aspirates were found to be colonized by gram-negative bacteria and fungi. This was followed by colonization of feces, burn, and sputum cultures. Biotype identification showed unidirectional colonization from the gastrointestinal tract to burns and upper airway. There were no cross infections between patients. Microbial colonization in severe burn patients was endogenous in nature and there were no cross infections. Thus, strict isolation is not necessary in burn centers, except during outbreaks of multi-resistant microorganisms.

Primary repair of penetrating colon injuries: a systematic review.

PubMed

Singer, Marc A; Nelson, Richard L

2002-12-01

Primary repair of penetrating colon injuries is an appealing management option; however, uncertainty about its safety persists. This study was conducted to compare the morbidity and mortality of primary repair with fecal diversion in the management of penetrating colon injuries by use of a meta-analysis of randomized, prospective trials. We searched for prospective, randomized trials in MEDLINE (1966 to November 2001), the Cochrane Library, and EMBase using the terms colon, penetrating, injury, colostomy, prospective, and randomized. Studies were included if they were randomized, controlled trials that compared the outcomes of primary repair with fecal diversion in the management of penetrating colon injuries. Five studies were included. Reviewers performed data extraction independently. Outcomes evaluated from each trial included mortality, total complications, infectious complications, intra-abdominal infections, wound complications, penetrating abdominal trauma index, and length of stay. Peto odds ratios for combined effect were calculated with a 95 percent confidence interval for each outcome. Heterogeneity was also assessed for each outcome. The penetrating abdominal trauma index of included subjects did not differ significantly between studies. Mortality was not significantly different between groups (odds ratio, 1.70; 95 percent confidence interval, 0.51-5.66). However, total complications (odds ratio, 0.28; 95 percent confidence interval, 0.18-0.42), total infectious complications (odds ratio, 0.41; 95 percent confidence interval, 0.27-0.63), abdominal infections including dehiscence (odds ratio, 0.59; 95 percent confidence interval, 0.38-0.94), abdominal infections excluding dehiscence (odds ratio, 0.52; 95 percent confidence interval, 0.31-0.86), wound complications including dehiscence (odds ratio, 0.55; 95 percent confidence interval, 0.34-0.89), and wound complications excluding dehiscence (odds ratio, 0.43; 95 percent confidence interval, 0

The Value of Continuity between Primary Care and Surgical Care in Colon Cancer.

PubMed

Hussain, Tanvir; Chang, Hsien-Yen; Luu, Ngoc-Phuong; Pollack, Craig Evan

2016-01-01

Improving continuity between primary care and cancer care is critical for improving cancer outcomes and curbing cancer costs. A dimension of continuity, we investigated how regularly patients receive their primary care and surgical care for colon cancer from the same hospital and whether this affects mortality and costs. Using Surveillance, Epidemiology, and End Results Program Registry (SEER)-Medicare data, we performed a retrospective cohort study of stage I-III colon cancer patients diagnosed between 2000 and 2009. There were 23,305 stage I-III colon cancer patients who received primary care in the year prior to diagnosis and underwent operative care for colon cancer. Patients were assigned to the hospital where they had their surgery and to their primary care provider's main hospital, and then classified according to whether these two hospitals were same or different. Outcomes examined were hazards for all-cause mortality, subhazard for colon cancer specific mortality, and generalized linear estimate for costs at 12 months, from propensity score matched models. Fifty-two percent of stage I-III colon patients received primary care and surgical care from the same hospital. Primary care and surgical care from the same hospital was not associated with reduced all-cause or colon cancer specific mortality, but was associated with lower inpatient, outpatient, and total costs of care. Total cost difference was $8,836 (95% CI $2,746-$14,577), a 20% reduction in total median cost of care at 12 months. Receiving primary care and surgical care at the same hospital, compared to different hospitals, was associated with lower costs but still similar survival among stage I-III colon cancer patients. Nonetheless, health care policy which encourages further integration between primary care and cancer care in order to improve outcomes and decrease costs will need to address the significant proportion of patients receiving health care across more than one hospital.

Dedifferentiated Liposarcoma Mimicking a Primary Colon Mass.

PubMed

Hollowoa, Blake; Lamps, Laura W; Mizell, Jason S; English, George W; Bridge, Julia A; Ram, Roopa; Gardner, Jerad M

2018-04-01

Dedifferentiated liposarcoma is typically a nonlipogenic high-grade sarcoma that arises from well-differentiated liposarcoma. It most commonly presents as a large mass in the retroperitoneum. Significant involvement of the gastrointestinal tract by dedifferentiated liposarcoma is uncommon. We present a unique case of dedifferentiated liposarcoma radiographically mimicking a primary colon mass with resulting intussusception; stranding of the adjacent adipose tissue was presumed to be a secondary reactive change. On histopathologic analysis of the hemicolectomy specimen, a high-grade sarcoma was seen growing through the colonic wall, and the majority of the surrounding pericolonic adipose tissue was actually composed of well-differentiated liposarcoma with characteristic fibrous bands rather than benign fat with reactive fibrosis. This case raises awareness that well-differentiated liposarcoma and dedifferentiated liposarcoma can rarely present as a primary intestinal mass mimicking colon cancer or other more common entities. When radiographic examination shows a perigastrointestinal or retroperitoneal fatty mass and/or stranding of the fat adjacent to a solid gastrointestinal mass, this unusual scenario should be considered in the radiologic differential diagnosis. Pathologists should keep dedifferentiated liposarcoma in the initial histologic differential diagnosis for any high-grade spindle cell tumor of the retroperitoneum or intra-abdominal visceral organs.

Bacterial Colonization and Tissue Compatibility of Denture Base Resins.

PubMed

Olms, Constanze; Yahiaoui-Doktor, Maryam; Remmerbach, Torsten W; Stingu, Catalina Suzana

2018-06-15

Currently, there is minimal clinical data regarding biofilm composition on the surface of denture bases and the clinical tissue compatibility. Therefore, the aim of this experimental study was to compare the bacterial colonization and the tissue compatibility of a hypoallergenic polyamide with a frequently used PMMA resin tested intraorally in a randomized split-mouth design. Test specimens made of polyamide ( n = 10) and PMMA ( n = 10) were attached over a molar band appliance in oral cavity of 10 subjects. A cytological smear test was done from palatal mucosa at baseline and after four weeks. The monolayers were inspected for micronuclei. After four weeks in situ, the appliance was removed. The test specimens were immediately cultivated on non-selective and selective nutrient media. All growing colonies were identified using VITEK-MS. The anonymized results were analyzed descriptively. A total of 110 different bacterial species could be isolated, including putative pathogens. An average of 17.8 different bacterial species grew on the PMMA specimens, and 17.3 on the polyamide specimens. The highest number of different bacterial species was n = 24, found on a PMMA specimen. On the two specimens, a similar bacterial distribution was observed. Micronuclei, as a marker for genotoxic potential of dental materials, were not detected. This study indicates that the composition of bacterial biofilm developed on these resins after four weeks is not influenced by the type of resin itself. The two materials showed no cytological differences. This investigation suggests that polyamide and PMMA are suitable for clinical use as denture base material.

Consistent changes in the taxonomic structure and functional attributes of bacterial communities during primary succession.

PubMed

Ortiz-Álvarez, Rüdiger; Fierer, Noah; de Los Ríos, Asunción; Casamayor, Emilio O; Barberán, Albert

2018-02-20

Ecologists have long studied primary succession, the changes that occur in biological communities after initial colonization of an environment. Most of this work has focused on succession in plant communities, laying the conceptual foundation for much of what we currently know about community assembly patterns over time. Because of their prevalence and importance in ecosystems, an increasing number of studies have focused on microbial community dynamics during succession. Here, we conducted a meta-analysis of bacterial primary succession patterns across a range of distinct habitats, including the infant gut, plant surfaces, soil chronosequences, and aquatic environments, to determine whether consistent changes in bacterial diversity, community composition, and functional traits are evident over the course of succession. Although these distinct habitats harbor unique bacterial communities, we were able to identify patterns in community assembly that were shared across habitat types. We found an increase in taxonomic and functional diversity with time while the taxonomic composition and functional profiles of communities became less variable (lower beta diversity) in late successional stages. In addition, we found consistent decreases in the rRNA operon copy number and in the high-efficient phosphate assimilation process (Pst system) suggesting that reductions in resource availability during succession select for taxa adapted to low-resource conditions. Together, these results highlight that, like many plant communities, microbial communities also exhibit predictable patterns during primary succession.

Does implant coating with antibacterial-loaded hydrogel reduce bacterial colonization and biofilm formation in vitro?

PubMed

Drago, Lorenzo; Boot, Willemijn; Dimas, Kostantinos; Malizos, Kostantinos; Hänsch, Gertrud M; Stuyck, Jos; Gawlitta, Debby; Romanò, Carlo L

2014-11-01

Implant-related infections represent one of the most severe complications in orthopaedics. A fast-resorbable, antibacterial-loaded hydrogel may reduce or prevent bacterial colonization and biofilm formation of implanted biomaterials. We asked: (1) Is a fast-resorbable hydrogel able to deliver antibacterial compounds in vitro? (2) Can a hydrogel (alone or antibacterial-loaded) coating on implants reduce bacterial colonization? And (3) is intraoperative coating feasible and resistant to press-fit implant insertion? We tested the ability of Disposable Antibacterial Coating (DAC) hydrogel (Novagenit Srl, Mezzolombardo, Italy) to deliver antibacterial agents using spectrophotometry and a microbiologic assay. Antibacterial and antibiofilm activity were determined by broth microdilution and a crystal violet assay, respectively. Coating resistance to press-fit insertion was tested in rabbit tibias and human femurs. Complete release of all tested antibacterial compounds was observed in less than 96 hours. Bactericidal and antibiofilm effect of DAC hydrogel in combination with various antibacterials was shown in vitro. Approximately 80% of the hydrogel coating was retrieved on the implant after press-fit insertion. Implant coating with an antibacterial-loaded hydrogel reduces bacterial colonization and biofilm formation in vitro. A fast-resorbable, antibacterial-loaded hydrogel coating may help prevent implant-related infections in orthopaedics. However, further validation in animal models and properly controlled human studies is required.

Primary repair of colon injuries: clinical study of nonselective approach.

PubMed

Lazovic, Ranko G; Barisic, Goran I; Krivokapic, Zoran V

2010-12-02

This study was designed to determine the role of primary repair and to investigate the possibility of expanding indications for primary repair of colon injuries using nonselective approach. Two groups of patients were analyzed. Retrospective (RS) group included 30 patients managed by primary repair or two stage surgical procedure according to criteria published by Stone (S/F) and Flint (Fl). In this group 18 patients were managed by primary repair. Prospective (PR) group included 33 patients with primary repair as a first choice procedure. In this group, primary repair was performed in 30 cases. Groups were comparable regarding age, sex, and indexes of trauma severity. Time between injury and surgery was shorter in PR group, (1.3 vs. 3.1 hours). Stab wounds were more frequent in PR group (9:2), and iatrogenic lesions in RS group (6:2). Associated injuries were similar, as well as segmental distribution of colon injuries. S/F criteria and Flint grading were similar.In RS group 15 primary repairs were successful, while in two cases relaparotomy and colostomy was performed due to anastomotic leakage. One patient died. In PR group, 25 primary repairs were successful, with 2 immediate and 3 postoperative (7-10 days) deaths, with no evidence of anastomotic leakage. Results of this study justify more liberal use of primary repair in early management of colon injuries. Current Controlled Trials ISRCTN94682396.

Bacterial adaptation to the gut environment favors successful colonization: microbial and metabonomic characterization of a simplified microbiota mouse model.

PubMed

Rezzonico, Enea; Mestdagh, Renaud; Delley, Michèle; Combremont, Séverine; Dumas, Marc-Emmanuel; Holmes, Elaine; Nicholson, Jeremy; Bibiloni, Rodrigo

2011-01-01

Rodent models harboring a simple yet functional human intestinal microbiota provide a valuable tool to study the relationships between mammals and their bacterial inhabitants. In this study, we aimed to develop a simplified gnotobiotic mouse model containing 10 easy-to-grow bacteria, readily available from culture repositories, and of known genome sequence, that overall reflect the dominant commensal bacterial makeup found in adult human feces. We observed that merely inoculating a mix of fresh bacterial cultures into ex-germ free mice did not guarantee a successful intestinal colonization of the entire bacterial set, as mice inoculated simultaneously with all strains only harbored 3 after 21 d. Therefore, several inoculation procedures were tested and levels of individual strains were quantified using molecular tools. Best results were obtained by inoculating single bacterial strains into individual animals followed by an interval of two weeks before allowing the animals to socialize to exchange their commensal microbes. Through this procedure, animals were colonized with almost the complete bacterial set (9/10). Differences in the intestinal composition were also reflected in the urine and plasma metabolic profiles, where changes in lipids, SCFA, and amino acids were observed. We conclude that adaptation of bacterial strains to the host's gut environment (mono-colonization) may predict a successful establishment of a more complex microbiota in rodents.

Increased risk of pneumonia and bronchiolitis after bacterial colonization of the airways as neonates.

PubMed

Vissing, Nadja H; Chawes, Bo L K; Bisgaard, Hans

2013-11-15

The frequency of pneumonia and bronchiolitis exhibits considerable variation in otherwise healthy children, and suspected risk factors explain only a minor proportion of the variation. We hypothesized that alterations in the airway microbiome in early life may be associated with susceptibility to pneumonia and bronchiolitis in young children. To investigate the relation between neonatal airway colonization and pneumonia and bronchiolitis during the first 3 years of life. Participants comprised children of the Copenhagen Prospective Studies on Asthma in Childhood2000 (COPSAC2000) cohort, a prospective birth cohort study of 411 children born to mothers with asthma. Aspirates from the hypopharynx at age 4 weeks were cultured for Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus. Clinical information on pneumonia and bronchiolitis within the first 3 years of life was prospectively collected by the research physicians at the center. Analyses were adjusted for covariates associated with pneumonia and bronchiolitis and bacterial airway colonization. Hypopharyngeal aspirates and full clinical follow-up until 3 years of age were available for 265 children. Of these, 56 (21%) neonates were colonized with S. pneumoniae, H. influenzae, and/or M. catarrhalis at 4 weeks of age. Colonization with at least one of these microorganisms (but not S. aureus) was significantly associated with increased incidence of pneumonia and bronchiolitis (adjusted incidence rate ratio, 1.79 [1.29-2.48]; P < 0.005) independently of concurrent or later asthma. Neonatal airway colonization with S. pneumoniae, H. influenzae, or M. catarrhalis is associated with increased risk of pneumonia and bronchiolitis in early life independently of asthma. This suggests a role of pathogenic bacterial colonization of the airways in neonates for subsequent susceptibly to pneumonia and bronchiolitis.

Bacterial Community Composition Associated with Pyrogenic Organic Matter (Biochar) Varies with Pyrolysis Temperature and Colonization Environment

PubMed Central

Dai, Zhongmin; Barberán, Albert; Li, Yong; Brookes, Philip C.

2017-01-01

ABSTRACT Microbes that colonize pyrogenic organic matter (PyOM) (also called biochar) play an important role in PyOM mineralization and crucially affect soil biogeochemical cycling, while the microbial community composition associated with PyOM particles is poorly understood. We generated two manure-based PyOMs with different characteristics (PyOM pyrolyzed at the low temperature of 300°C [i.e., PyOM300] and at the high temperature of 700°C [i.e., PyOM700]) and added them to high-carbon (4.15%) and low-C (0.37%) soil for microbial colonization. 16S rRNA gene sequencing showed that Actinobacteria, particularly Actinomycetales, was the dominant taxon in PyOM, regardless of the PyOM pyrolysis temperature and soil type. Bacterial communities associated with PyOM particles from high-C soils were similar to those in non-PyOM-amended soils. PyOM300 had higher total microbial activity and more differential bacterial communities than PyOM700. More bacterial operational taxonomic units (OTUs) preferentially thrived on the low-pyrolysis-temperature PyOM, while some specific OTUs thrived on high-pyrolysis-temperature PyOM. In particular, Chloroflexi species tended to be more prevalent in high-pyrolysis-temperature PyOM in low-C soils. In conclusion, the differences in colonized bacterial community composition between the different PyOMs were strongly influenced by the pyrolysis temperatures of PyOM, i.e., under conditions of easily mineralizable C or fused aromatic C, and by other properties, e.g., pH, surface area, and nutrient content. IMPORTANCE Pyrogenic organic matter (PyOM) is widely distributed in soil and fluvial ecosystems and plays an important role in biogeochemical cycling. Many studies have reported changes in soil microbial communities stimulated by PyOM, but very little is known about the microbial communities associated with PyOM. The microbes that colonize PyOMs can participate in the mineralization of PyOM, so changing its structure affects the fate of Py

Bacterial Community Composition Associated with Pyrogenic Organic Matter (Biochar) Varies with Pyrolysis Temperature and Colonization Environment.

PubMed

Dai, Zhongmin; Barberán, Albert; Li, Yong; Brookes, Philip C; Xu, Jianming

2017-01-01

Microbes that colonize pyrogenic organic matter (PyOM) (also called biochar) play an important role in PyOM mineralization and crucially affect soil biogeochemical cycling, while the microbial community composition associated with PyOM particles is poorly understood. We generated two manure-based PyOMs with different characteristics (PyOM pyrolyzed at the low temperature of 300°C [i.e., PyOM300] and at the high temperature of 700°C [i.e., PyOM700]) and added them to high-carbon (4.15%) and low-C (0.37%) soil for microbial colonization. 16S rRNA gene sequencing showed that Actinobacteria , particularly Actinomycetales , was the dominant taxon in PyOM, regardless of the PyOM pyrolysis temperature and soil type. Bacterial communities associated with PyOM particles from high-C soils were similar to those in non-PyOM-amended soils. PyOM300 had higher total microbial activity and more differential bacterial communities than PyOM700. More bacterial operational taxonomic units (OTUs) preferentially thrived on the low-pyrolysis-temperature PyOM, while some specific OTUs thrived on high-pyrolysis-temperature PyOM. In particular, Chloroflexi species tended to be more prevalent in high-pyrolysis-temperature PyOM in low-C soils. In conclusion, the differences in colonized bacterial community composition between the different PyOMs were strongly influenced by the pyrolysis temperatures of PyOM, i.e., under conditions of easily mineralizable C or fused aromatic C, and by other properties, e.g., pH, surface area, and nutrient content. IMPORTANCE Pyrogenic organic matter (PyOM) is widely distributed in soil and fluvial ecosystems and plays an important role in biogeochemical cycling. Many studies have reported changes in soil microbial communities stimulated by PyOM, but very little is known about the microbial communities associated with PyOM. The microbes that colonize PyOMs can participate in the mineralization of PyOM, so changing its structure affects the fate of PyOMs and

Reduced toll-like receptor 4 and substance P gene expression is associated with airway bacterial colonization in children.

PubMed

Grissell, Terry V; Chang, Anne B; Gibson, Peter G

2007-04-01

Neuro-immune interactions are increasingly relevant to human health and disease. The neuropeptide Substance P also has antibacterial activity and bears similarities to the innate immune antibacterial defensins. This suggests possible co-regulation of neuropeptide and innate immune mediators. In this study, non-bronchoscopic bronchoalveolar lavage (BAL) was performed on 69 children. BAL was examined for cellular profile, microbiology (bacteria, virus) and gene expression for TLRs 2, 3, 4; chemokine receptors (CCR3, CCR5, CXCR1); neurotrophins and neurokinin genes (TAC1, TAC3, CGRP, NGF). In children with bacterial colonization (n=10) there was an airway inflammatory response with increased BAL neutrophils, IL-8 protein, and CXCR1 expression. Substance P (TAC1) and TLR4 RNA expression were reduced in children with bacterial colonization. TLR3 mRNA was increased in 7.2% (n=5) children with rhinovirus, and there was a non-significant trend to increased TLR2. There is evidence for co-regulation of neurokinin (TAC1) and TLR4 gene expression in airway cells from children with airway bacterial colonization and their reduced expression may be associated with an impaired bacterial clearance. (c) 2007 Wiley-Liss, Inc.

Bacterial Community Profiling of Plastic Litter in the Belgian Part of the North Sea.

PubMed

De Tender, Caroline A; Devriese, Lisa I; Haegeman, Annelies; Maes, Sara; Ruttink, Tom; Dawyndt, Peter

2015-08-18

Bacterial colonization of marine plastic litter (MPL) is known for over four decades. Still, only a few studies on the plastic colonization process and its influencing factors are reported. In this study, seafloor MPL was sampled at different locations across the Belgian part of the North Sea to study bacterial community structure using 16S metabarcoding. These marine plastic bacterial communities were compared with those of sediment and seawater, and resin pellets sampled on the beach, to investigate the origin and uniqueness of plastic bacterial communities. Plastics display great variation of bacterial community composition, while each showed significant differences from those of sediment and seawater, indicating that plastics represent a distinct environmental niche. Various environmental factors correlate with the diversity of MPL bacterial composition across plastics. In addition, intrinsic plastic-related factors such as pigment content may contribute to the differences in bacterial colonization. Furthermore, the differential abundance of known primary and secondary colonizers across the various plastics may indicate different stages of bacterial colonization, and may confound comparisons of free-floating plastics. Our studies provide insights in the factors that shape plastic bacterial colonization and shed light on the possible role of plastic as transport vehicle for bacteria through the aquatic environment.

Photochemical coatings for the prevention of bacterial colonization.

PubMed

Dunkirk, S G; Gregg, S L; Duran, L W; Monfils, J D; Haapala, J E; Marcy, J A; Clapper, D L; Amos, R A; Guire, P E

1991-10-01

Biomaterials are being used with increasing frequency for tissue substitution. Implantable, prosthetic devices are instrumental in the saving of patients' lives and enhancing the quality of life for many others. However, the greatest barrier to expanding the use of biomedical devices is the high probability of bacterial adherence and proliferation, causing very difficult and often untreatable medical-device centered infections. The difficulty in treating such infections results in great danger to the patient, and usually retrieval of the device with considerable pain and suffering. Clearly, development of processes that make biomedical devices resistant to bacterial adherence and colonization would have widespread application in the field of biomedical technology. A photochemical surface modification process is being investigated as a generic means of applying antimicrobial coatings to biomedical devices. The photochemical process results in covalent immobilization of coatings to all classes of medical device polymers. A discussion of the photochemical surface modification process and preliminary results demonstrating the success of photochemical coatings in formulating microbial-resistant surfaces are presented in this paper.

Differences in Bacterial Colonization and Biofilm Formation Property of Uropathogens between the Two most Commonly used Indwelling Urinary Catheters.

PubMed

Verma, Amit; Bhani, Deepa; Tomar, Vinay; Bachhiwal, Rekha; Yadav, Shersingh

2016-06-01

Catheter Associated Urinary Tract Infections (CAUTI) are one of the most common cause of nosocomial infections. Many bacterial species show biofilm production, which provides survival benefit to them by providing protection from environmental stresses and causing decreased susceptibility to antimicrobial agents. Two most common types of catheters used in our setup are pure silicone catheter and silicone coated latex catheter. The advantage of pure silicone catheter for long term catheterization is well established. But there is still a controversy about any advantage of the silicone catheter regarding bacterial colonization rates and their biofilm production property. The aim of our study was to compare the bacterial colonization and the biofilm formation property of the colonizing bacteria in patients with indwelling pure silicone and silicone coated latex catheters. This prospective observational study was conducted in the Urology Department of our institute. Patients who needed catheterization for more than 5 days during the period July 2015 to January 2016 and had sterile precatheterisation urine were included in the study. Patients were grouped into 2 groups of 50 patients each, Group A with the pure silicone catheter and Group B with the silicone coated latex catheter. Urine culture was done on the 6(th) day of indwelling urinary catheter drainage. If growth was detected, then that bacterium was tested for biofilm production property by tissue culture plate method. Statistical analyses were performed using the Statistical Package for the Social Science Version 22 (SPSS-22). After 5 days of indwelling catheterization, the pure silicone catheter had significantly less bacterial colonization than the silicone coated latex catheter (p-value=0.03) and the biofilm forming property of colonizing bacteria was also significantly less in the pure silicone catheter as compared to the silicone coated latex catheter (p-value=0.02). There were no significant differences in

Bacterial colonization of the phyllosphere of mediterranean perennial species as influenced by leaf structural and chemical features.

PubMed

Yadav, R K P; Karamanoli, K; Vokou, D

2005-08-01

In this study, we assessed various leaf structural and chemical features as possible predictors of the size of the phyllosphere bacterial population in the Mediterranean environment. We examined eight perennial species, naturally occurring and coexisting in the same area, in Halkidiki (northern Greece). They are Arbutus unedo, Quercus coccifera, Pistacia lentiscus, and Myrtus communis (evergreen sclerophyllous species), Lavandula stoechas and Cistus incanus (drought semi-deciduous species), and Calamintha nepeta and Melissa officinalis (non-woody perennial species). M. communis, L. stoechas, C. nepeta, and M. officinalis produce essential oil in substantial quantities. We sampled summer leaves from these species and (1) estimated the size of the bacterial population of their phyllosphere, (2) estimated the concentration of different leaf constituents, and (3) studied leaf morphological and anatomical features and expressed them in a quantitative way. The aromatic plants are on average more highly colonized than the other species, whereas the non-woody perennials are more highly colonized than the woody species. The population size of epiphytic bacteria is positively correlated with glandular and non-glandular trichome densities, and with water and phosphorus contents; it is negatively correlated with total phenolics content and the thickness of the leaf, of the mesophyll, and of the abaxial epidermis. No correlation was found with the density of stomata, the nitrogen, and the soluble sugar contents. By regression tree analysis, we found that the leaf-microbe system can be effectively described by three leaf attributes with leaf water content being the primary explanatory attribute. Leaves with water content >73% are the most highly colonized. For leaves with water content <73%, the phosphorus content, with a critical value of 1.34 mg g(-1) d.w., is the next explanatory leaf attribute, followed by the thickness of the adaxial epidermis. Leaves higher in phosphorus

Temporal changes of the bacterial community colonizing wheat straw in the cow rumen.

PubMed

Jin, Wei; Wang, Ying; Li, Yuanfei; Cheng, Yanfen; Zhu, Weiyun

2018-04-01

This study used Miseq pyrosequencing and scanning electron microscopy to investigate the temporal changes in the bacterial community tightly attached to wheat straw in the cow rumen. The wheat straw was incubated in the rumens and samples were recovered at various times. The wheat straw degradation exhibited three phases: the first degradation phase occurred within 0.5 h, and the second degradation phase occurred after 6 h, with a stalling phase occurring between 0.5 and 6 h. Scanning electron microscopy revealed the colonization of the microorganisms on the wheat straw over time. The bacterial communities at 0.5, 6, 24, and 72 h were determined, corresponding to the degradation phases. Firmicutes and Bacteroidetes were the two most dominant phyla in the bacterial communities at the four time points. Principal coordinate analysis (PCoA) showed that the bacterial communities at the four time points were distinct from each other. The wheat straw-associated bacteria stabilized at the phylum level after 0.5 h of rumen incubation, and only modest phylum-level and family-level changes were observed for most taxa between 0.5 h and 72 h. The relative abundance of the dominant genera, Butyrivibrio, Coprococcus, Ruminococcus, Succiniclasticum, Clostridium, Prevotella, YRC22, CF231, and Treponema, changed significantly over time (P < .05). However, at the genus level, unclassified taxa accounted for 70.3% ± 6.1% of the relative abundance, indicating their probable importance in the degradation of wheat straw as well as in the temporal changes of the bacterial community. Thus, understanding the function of these unclassified taxa is of great importance for targeted improvement of forage use efficiency in ruminants. Collectively, our results revealed distinct degradation phases of wheat straw and corresponding changes in the colonized bacterial community. Copyright © 2018 Elsevier Ltd. All rights reserved.

Influence of clinical history on airways bacterial colonization in subjects with chronic tracheostomy.

PubMed

Lusuardi, M; Capelli, A; Cerutti, C G; Gnemmi, I; Zaccaria, S; Donner, C F

2000-05-01

Patients with chronic tracheostomy are subject to significant bacterial colonization of the airways, a risk factor for respiratory infections. The aim of our study was to verify whether bacterial colonization and humoral immune response in the airways can be influenced by the disease which led to chronic respiratory failure and tracheostomy. Thirty-nine clinically stable outpatients with chronic tracheostomy were considered: 24 were affected by chronic obstructive pulmonary disease (COPD) (mean age 66 years, range 54-78, M/F 19/3; months since tracheostomy 23, range 3-62), 15 by restrictive lung disease (RLD) (12 thoracic wall deformities, three neuromuscular disease; age 57 years, range 41-72; M/F 3/12, months since tracheostomy 22, range 2-68). Recent antibiotic or corticosteroid treatments (< 1 month) were among exclusion criteria. Bacterial counts were assessed in tracheobronchial secretions with the method of serial dilutions. Identification of bacterial strains was performed by routine methods. Albumin, IgG, A, and M were measured in airways secretions with an immunoturbidimetric method. No significant differences were found between the two groups as regards either the quantitative bacterial cultures (RLD 81.4, 2.6-4200 x 10(4); COPD 75.9, 1.0-1530 x 10(4) colony forming units (cfu)/ml, geometric mean, range) or the prevalence of the main bacterial strains, (Pseudomonas species: 38 and 37%, Serratia marcescens: 31 and 23%, Staphylococcus aureus: 14 and 6%, Proteus species: 3 and 8%, for RLD and COPD respectively) as a percentage of total strains isolated (RLD = 26, COPD = 48). Immunoglobulin levels did not show significant differences, apart from being higher in underweight subjects. We conclude that in our series of stable outpatients with chronic tracheostomy, bacteria-host interaction in the airways was not influenced by the clinical history.

Anti-plaque effect of a synergistic combination of green tea and Salvadora persica L. against primary colonizers of dental plaque.

PubMed

Abdulbaqi, Hayder Raad; Himratul-Aznita, Wan Harun; Baharuddin, Nor Adinar

2016-10-01

Green tea (Gt), leafs of Camellia sinensis var. assamica, is widely consumed as healthy beverage since thousands of years in Asian countries. Chewing sticks (miswak) of Salvadora persica L. (Sp) are traditionally used as natural brush to ensure oral health in developing countries. Both Gt and Sp extracts were reported to have anti-bacterial activity against many dental plaque bacteria. However, their combination has never been tested to have anti-bacterial and anti-adherence effect against primary dental plaque colonizers, playing an initial role in the dental plaque development, which was investigated in this study. Two-fold serial micro-dilution method was used to measure minimal inhibitory concentration (MIC) of aqueous extracts of Gt, Sp and their combinations. Adsorption to hexadecane was used to determine the cell surface hydrophobicity (CSH) of bacterial cells. Glass beads were used to mimic the hard tissue surfaces, and were coated with saliva to develop experimental pellicles for the adhesion of the primary colonizing bacteria. Gt aqueous extracts exhibited better anti-plaque effect than Sp aqueous extracts. Their combination, equivalent to 1/4 and 1/2 of MIC values of Gt and Sp extracts respectively, showed synergistic anti-plaque properties with fractional inhibitory concentration (FIC) equal to 0.75. This combination was found to significantly reduce CSH (p<0.05) and lower the adherence ability (p<0.003) towards experimental pellicles. Combination between Gt and Sp aqueous extracts exhibited synergistic anti-plaque activity, and could be used as a useful active agent to produce oral health care products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of the 10-Valent Pneumococcal Nontypeable Haemophilus influenzae Protein D–Conjugate Vaccine on Nasopharyngeal Bacterial Colonization in Young Children: A Randomized Controlled Trial

PubMed Central

van den Bergh, Menno R.; Spijkerman, Judith; Swinnen, Kristien M.; François, Nancy A.; Pascal, Thierry G.; Borys, Dorota; Schuerman, Lode; IJzerman, Ed P. F.; Bruin, Jacob P.; van der Ende, Arie; Veenhoven, Reinier H.; Sanders, Elisabeth A. M.

2013-01-01

Background. This study evaluated the effects of the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D–conjugate vaccine (PHiD-CV) on nasopharyngeal bacterial colonization compared with the 7-valent pneumococcal conjugate vaccine (7vCRM) in young children. Methods. A randomized controlled trial in the Netherlands, initiated 2 years after 7vCRM introduction, was conducted between 1 April 2008 and 1 December 2010. Infants (N = 780) received either PHiD-CV or 7vCRM (2:1) at 2, 3, 4, and 11–13 months of age. Nasopharyngeal samples taken at 5, 11, 14, 18, and 24 months of age were cultured to detect Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus. Polymerase chain reaction assays quantified H. influenzae and S. pneumoniae and confirmed H. influenzae as nontypeable (NTHi). Primary outcome measure was vaccine efficacy (VE) against NTHi colonization. Results. In both groups, NTHi colonization increased with age from 33% in 5-month-olds to 65% in 24-month-olds. Three months postbooster, VE against colonization was 0.5% (95% confidence interval [CI], −21.8% to 18.4%) and VE against acquisition 10.9% (95% CI, −31.3% to 38.9%). At each sampling moment, no differences between groups in either NTHi prevalence or H. influenzae density were detected. Streptococcus pneumoniae (range, 39%–57%), M. catarrhalis (range, 63%­–69%), and S. aureus (range, 9%–30%) colonization patterns were similar between groups. Conclusions. PHiD-CV had no differential effect on nasopharyngeal NTHi colonization or H. influenzae density in healthy Dutch children up to 2 years of age, implying that herd effects for NTHi are not to be expected. Other bacterial colonization patterns were also similar. Clinical Trials Registration NCT00652951. PMID:23118268

Evidence of variable bacterial colonization on coloured elastomeric ligatures during orthodontic treatment: An intermodular comparative study.

PubMed

Sharma, Ravish; Sharma, Kavita; Sawhney, Rajesh

2018-03-01

Besides, other factors, the choice of materials used as orthodontic ligatures could be one of the many tools to counter the effects of microbial adhesion, that culminates into dental ailments. Therefore, we assessed bacterial adhesion on elastomeric ligatures with special reference to coloured elastomeric rings during orthodontic treatment. A split mouth study, involving 240 samples of different elastomeric ligatures from forty orthodontic patients possessing good oral hygiene was carried out. The archwire was ligated to the brackets on both arches with elastomeric rings (superslick, clear transparent , blue and pink) at predetermined quadrants. After six weeks, ligatures from second premolars were removed and processed for bacterial enumeration using standard techniques. Bacterial counts were also determined for stimulated saliva samples taken at 0 and 6 weeks. A statistically significant difference in bacterial counts was obtained amongst different elastomeric modules used. Maximum bacterial counts were found on conventional pigmented elastomeric modules, followed by Superslick module and clear module. More number of bacteria associated with the conventional pink as compared to the conventional blue pigmented modules, however it was not statistically significant. The three bacterial genera Streptococcus Staphylococcus and Aerobic Lactobacilli adhered to elastomeric modules in following predominant pattern i.e. Conventional pink>Conventional Blue>Superslick>Clear. The studies evidenced colour and material dependent bacterial colonization on orthodontic modules and could be an indicator of bacterial biofilm forming potential based on surface chemistries and a clinically efficacious tool to redesign conventional and modified elastomeric rings as orthodontic ligation accessories. Key words: Bacterial colonization, biofilm, coloured elastomers, orthodontic ligatures.

Rapid bacterial colonization of low-density polyethylene microplastics in coastal sediment microcosms.

PubMed

Harrison, Jesse P; Schratzberger, Michaela; Sapp, Melanie; Osborn, A Mark

2014-09-23

Synthetic microplastics (≤5-mm fragments) are emerging environmental contaminants that have been found to accumulate within coastal marine sediments worldwide. The ecological impacts and fate of microplastic debris are only beginning to be revealed, with previous research into these topics having primarily focused on higher organisms and/or pelagic environments. Despite recent research into plastic-associated microorganisms in seawater, the microbial colonization of microplastics in benthic habitats has not been studied. Therefore, we employed a 14-day microcosm experiment to investigate bacterial colonization of low-density polyethylene (LDPE) microplastics within three types of coastal marine sediment from Spurn Point, Humber Estuary, U.K. Bacterial attachment onto LDPE within sediments was demonstrated by scanning electron microscopy and catalyzed reporter deposition fluorescence in situ hybridisation (CARD-FISH). Log-fold increases in the abundance of 16S rRNA genes from LDPE-associated bacteria occurred within 7 days with 16S rRNA gene numbers on LDPE surfaces differing significantly across sediment types, as shown by quantitative PCR. Terminal-restriction fragment length polymorphism (T-RFLP) analysis demonstrated rapid selection of LDPE-associated bacterial assemblages whose structure and composition differed significantly from those in surrounding sediments. Additionally, T-RFLP analysis revealed successional convergence of the LDPE-associated communities from the different sediments over the 14-day experiment. Sequencing of cloned 16S rRNA genes demonstrated that these communities were dominated after 14 days by the genera Arcobacter and Colwellia (totalling 84-93% of sequences). Attachment by Colwellia spp. onto LDPE within sediments was confirmed by CARD-FISH. These results demonstrate that bacteria within coastal marine sediments can rapidly colonize LDPE microplastics, with evidence for the successional formation of plastisphere-specific bacterial

Different Types of Dietary Fibers Trigger Specific Alterations in Composition and Predicted Functions of Colonic Bacterial Communities in BALB/c Mice

PubMed Central

Luo, Yuheng; Zhang, Ling; Li, Hua; Smidt, Hauke; Wright, André-Denis G.; Zhang, Keying; Ding, Xuemei; Zeng, Qiufeng; Bai, Shiping; Wang, Jianping; Li, Jian; Zheng, Ping; Tian, Gang; Cai, Jingyi; Chen, Daiwen

2017-01-01

Soluble dietary fibers (SDF) are fermented more than insoluble dietary fibers (IDF), but their effect on colonic bacterial community structure and function remains unclear. Thus, bacterial community composition and function in the colon of BALB/c mice (n = 7) fed with a high level (approximately 20%) of typical SDF, oat-derived β-glucan (G), microcrystalline cellulose (M) as IDF, or their mixture (GM), were compared. Mice in group G showed a lowest average feed intake (p < 0.05) but no change on the average body weight gain (p > 0.05) compared to other groups, which may be associated with the highest concentration of colonic propionate (p < 0.05) in these mice. The bacterial α-diversity of group G was significantly lower than other groups (p < 0.01). In group G, the relative abundance of bacteria belonging to the phylum Bacteroidetes was significantly increased, whereas bacteria from the phylum Firmicutes were significantly decreased (p < 0.01). The core bacteria for different treatments showed distinct differences. Bacteroides, Dehalobacterium, and Prevotella, including known acetogens and carbohydrate fermenting organisms, were significantly increased in relative abundance in group G. In contrast, Adlercreutzia, Odoribacter, and Coprococcus were significantly more abundant in group M, whereas Oscillospira, Desulfovibrio, and Ruminoccaceae, typical hydrogenotrophs equipped with multiple carbohydrate active enzymes, were remarkably enriched in group GM (p < 0.05). The relative abundance of bacteria from the three classes of Proteobacteria, Betaproteobacteria, Gammaproteobacteria (including Enterobacteriaceae) and Deltaproteobacteria, were significantly more abundant in group G, indicating a higher ratio of conditional pathogenic bacteria in mice fed dietary β-glucan in current study. The predicted colonic microbial function showed an enrichment of “Energy metabolism” and “Carbohydrate metabolism” pathways in mice from group G and M, suggesting that the

Different Types of Dietary Fibers Trigger Specific Alterations in Composition and Predicted Functions of Colonic Bacterial Communities in BALB/c Mice.

PubMed

Luo, Yuheng; Zhang, Ling; Li, Hua; Smidt, Hauke; Wright, André-Denis G; Zhang, Keying; Ding, Xuemei; Zeng, Qiufeng; Bai, Shiping; Wang, Jianping; Li, Jian; Zheng, Ping; Tian, Gang; Cai, Jingyi; Chen, Daiwen

2017-01-01

Soluble dietary fibers (SDF) are fermented more than insoluble dietary fibers (IDF), but their effect on colonic bacterial community structure and function remains unclear. Thus, bacterial community composition and function in the colon of BALB/c mice ( n = 7) fed with a high level (approximately 20%) of typical SDF, oat-derived β-glucan (G), microcrystalline cellulose (M) as IDF, or their mixture (GM), were compared. Mice in group G showed a lowest average feed intake ( p < 0.05) but no change on the average body weight gain ( p > 0.05) compared to other groups, which may be associated with the highest concentration of colonic propionate ( p < 0.05) in these mice. The bacterial α-diversity of group G was significantly lower than other groups ( p < 0.01). In group G, the relative abundance of bacteria belonging to the phylum Bacteroidetes was significantly increased, whereas bacteria from the phylum Firmicutes were significantly decreased ( p < 0.01). The core bacteria for different treatments showed distinct differences. Bacteroides , Dehalobacterium , and Prevotella , including known acetogens and carbohydrate fermenting organisms, were significantly increased in relative abundance in group G. In contrast, Adlercreutzia , Odoribacter , and Coprococcus were significantly more abundant in group M, whereas Oscillospira , Desulfovibrio , and Ruminoccaceae , typical hydrogenotrophs equipped with multiple carbohydrate active enzymes, were remarkably enriched in group GM ( p < 0.05). The relative abundance of bacteria from the three classes of Proteobacteria , Betaproteobacteria , Gammaproteobacteria (including Enterobacteriaceae ) and Deltaproteobacteria , were significantly more abundant in group G, indicating a higher ratio of conditional pathogenic bacteria in mice fed dietary β-glucan in current study. The predicted colonic microbial function showed an enrichment of "Energy metabolism" and "Carbohydrate metabolism" pathways in mice from group G and M, suggesting

Evaluation of quantitative PCR measurement of bacterial colonization of epithelial cells.

PubMed

Schmidt, Marcin T; Olejnik-Schmidt, Agnieszka K; Myszka, Kamila; Borkowska, Monika; Grajek, Włodzimierz

2010-01-01

Microbial colonization is an important step in establishing pathogenic or probiotic relations to host cells and in biofilm formation on industrial or medical devices. The aim of this work was to verify the applicability of quantitative PCR (Real-Time PCR) to measure bacterial colonization of epithelial cells. Salmonella enterica and Caco-2 intestinal epithelial cell line was used as a model. To verify sensitivity of the assay a competition of the pathogen cells to probiotic microorganism was tested. The qPCR method was compared to plate count and radiolabel approach, which are well established techniques in this area of research. The three methods returned similar results. The best quantification accuracy had radiolabel method, followed by qPCR. The plate count results showed coefficient of variation two-times higher than this of qPCR. The quantitative PCR proved to be a reliable method for enumeration of microbes in colonization assay. It has several advantages that make it very useful in case of analyzing mixed populations, where several different species or even strains can be monitored at the same time.

Taking Root: Enduring Effect of Rhizosphere Bacterial Colonization in Mangroves

PubMed Central

Pinto, Fernando N.; Egas, Conceição; Almeida, Adelaide; Cunha, Angela; Mendonça-Hagler, Leda C. S.; Smalla, Kornelia

2010-01-01

Background Mangrove forests are of global ecological and economic importance, but are also one of the world's most threatened ecosystems. Here we present a case study examining the influence of the rhizosphere on the structural composition and diversity of mangrove bacterial communities and the implications for mangrove reforestation approaches using nursery-raised plants. Methodology/Principal Findings A barcoded pyrosequencing approach was used to assess bacterial diversity in the rhizosphere of plants in a nursery setting, nursery-raised transplants and native (non-transplanted) plants in the same mangrove habitat. In addition to this, we also assessed bacterial composition in the bulk sediment in order to ascertain if the roots of mangrove plants affect sediment bacterial composition. We found that mangrove roots appear to influence bacterial abundance and composition in the rhizosphere. Due to the sheer abundance of roots in mangrove habitat, such an effect can have an important impact on the maintenance of bacterial guilds involved in nutrient cycling and other key ecosystem functions. Surprisingly, we also noted a marked impact of initial nursery conditions on the rhizosphere bacterial composition of replanted mangrove trees. This result is intriguing because mangroves are periodically inundated with seawater and represent a highly dynamic environment compared to the more controlled nursery environment. Conclusions/Significance In as far as microbial diversity and composition influences plant growth and health, this study indicates that nursery conditions and early microbial colonization patterns of the replants are key factors that should be considered during reforestation projects. In addition to this, our results provide information on the role of the mangrove rhizosphere as a habitat for bacteria from estuarine sediments. PMID:21124923

Chemopreventive potential of in vitro fermented nuts in LT97 colon adenoma and primary epithelial colon cells.

PubMed

Schlörmann, Wiebke; Lamberty, Julia; Lorkowski, Stefan; Ludwig, Diana; Mothes, Henning; Saupe, Christian; Glei, Michael

2017-05-01

Due to their beneficial nutritional profile the consumption of nuts contributes to a healthy diet and might reduce colon cancer risk. To get closer insights into potential mechanisms, the chemopreventive potential of different in vitro fermented nut varieties regarding the modulation of genes involved in detoxification (CAT, SOD2, GSTP1, GPx1) and cell cycle (p21, cyclin D2) as well as proliferation and apoptosis was examined in LT97 colon adenoma and primary epithelial colon cells. Fermentation supernatants (FS) of nuts significantly induced mRNA expression of CAT (up to 4.0-fold), SOD2 (up to 2.5-fold), and GSTP1 (up to 2.3-fold), while GPx1 expression was significantly reduced by all nut FS (0.8 fold on average). Levels of p21 mRNA were significantly enhanced (up to 2.6-fold), whereas all nut FS significantly decreased cyclin D2 expression (0.4-fold on average). In primary epithelial cells, expression of CAT (up to 3.5-fold), GSTP1 (up to 3.0-fold), and GPx1 (up to 3.9-fold) was increased, whereas p21 and cyclin D2 levels were not influenced. Nut FS significantly inhibited growth of LT97 cells and increased levels of early apoptotic cells (8.4% on average) and caspase 3 activity (4.6-fold on average), whereas caspase 3 activity was not modulated in primary colon cells. The differential modulation of genes involved in detoxification and cell cycle together with an inhibition of proliferation and induction of apoptosis in adenoma cells might contribute to chemopreventive effects of nuts regarding colon cancer. © 2017 Wiley Periodicals, Inc.

Factors Influencing Biofilm Formation in Streams: Bacterial Colonization, Detachment and Transport

NASA Astrophysics Data System (ADS)

Leff, L.

2005-05-01

Surfaces in aquatic systems develop biofilms containing microorganisms embedded in complex extracellular matrices. Properties of the surface, water, and colonizing organisms impact biofilm formation. Biofilm features, physical disturbance, and interactions between macro- and microscopic organisms, in turn, influence detachment. In spite of the importance of biofilms, much remains unknown about factors controlling biofilms in streams and other natural environments. Experiments were conducted in the laboratory and field to examine factors influencing surface colonization, and subsequent biofilm formation, and detachment. Microscopy methods, fluorescent in situ hybridization and confocal laser microscopy, were used to examine responses, including abundance of different taxa and biofilm depth. From these experiments, we determined that different taxa differ in their colonization ability based on properties like extracellular polysaccharide production and surface features, like hydrophobicity and that water chemistry, such as magnesium concentration, plays an important role. Moreover, detachment varies among taxa and with environmental conditions and may be enhanced by activities of macrofauna. Variation in detachment, in turn, influences bacterial transport and subsequent re-attachment. Overall, examination of attachment, detachment, and interactions in biofilms allows us to begin to understand how environmental conditions may impact the function of these communities in aquatic systems.

Variation in local carrying capacity and the individual fate of bacterial colonizers in the phyllosphere

PubMed Central

Remus-Emsermann, Mitja N P; Tecon, Robin; Kowalchuk, George A; Leveau, Johan H J

2012-01-01

Using a phyllosphere model system, we demonstrated that the term ‘carrying capacity', as it is commonly used in microbial ecology, needs to be understood as the sum of many ‘local carrying capacities' in order to better explain and predict the course and outcome of bacterial colonization of an environment. Using a green fluorescent protein-based bioreporter system for the quantification of reproductive success (RS) in individual Erwinia herbicola cells, we were able to reconstruct the contribution of individual immigrants to bacterial population sizes on leaves. Our analysis revealed that plant foliage represents to bacteria an environment where individual fate is determined by the local carrying capacity of the site where an immigrant cell lands. With increasing inoculation densities, the RS of most immigrants declined, suggesting that local carrying capacity under the tested conditions was linked to local nutrient availability. Fitting the observed experimental data to an adapted model of phyllosphere colonization indicated that there might exist three types of sites on leaves, which differ in their frequency of occurrence and local carrying capacity. Specifically, our data were consistent with a leaf environment that is characterized by few sites where individual immigrants can produce high numbers of offspring, whereas the remainder of the leaf offered an equal number of sites with low and medium RS. Our findings contribute to a bottom–up understanding of bacterial colonization of leaf surfaces, which includes a quantifiable role of chance in the experience at the individual level and in the outcome at the population level. PMID:22258099

Primary repair of civilian colon injuries is safe in the damage control scenario.

PubMed

Kashuk, Jeffry L; Cothren, C Clay; Moore, Ernest E; Johnson, Jeffrey L; Biffl, Walter L; Barnett, Carlton C

2009-10-01

Although the safety of primary repair/anastomosis for civilian colon injuries after standard laparotomy (SL) has been established, recent civilian and military reports have questioned the advisability of this technique in the patient requiring damage control laparotomy (DL). We hypothesized that, even in the high-risk DL group, primary repair could be safely used after patient stabilization and that the open abdomen would facilitate the safety of this procedure. All patients admitted to our level 1 trauma center with a colon injury over a 7-year period were reviewed from a prospectively collected database. Patients were categorized as having undergone either SL or DL at initial operation. Primary variables of interest were as follows: injury patterns; method of primary repair (suture repair, resection and primary anastomosis, resection and delayed anastomosis); diversion techniques (planned diversion or diversion for anastomotic dehiscence); and colon-related morbidity and mortality. High-risk status in the DL group was identified by the following physiologic variables: mean injury severity score (ISS), red blood cell (RBC) transfusions, ventilator days, and intensive care unit (ICU) duration of stay. During the study period, 309 patients had colonic wounds identified at laparotomy. Of these 309 patients, 280 (91%) underwent SL, of which 277 (98.9%) had primary colonic repair/anastomosis. In the SL group, 1 (0.3%) patient required diversion for subsequent leak and 2 (0.6%) patients had planned diversion The remaining 29 hemodynamically unstable patients required DL. Mean +/- standard deviation indices of injury severity in this group included: ISS = 36.2 +/- 15.8, RBC = 28.7 +/- 25.4 units, ventilator days = 20.1 +/- 16.3, ICU duration of stay = 29.5 +/- 21.6 days. Of the 29 patients in the DL group, 21 (72%) had bowel continuity successfully reestablished in 2.6 +/- 2 days after initial attempts at primary suture repair or resection/anastomosis. A total of 4 (16

Absence of bacterial colonization of the airways after therapeutic rigid bronchoscopy without stenting.

PubMed

Noppen, M; Piérard, D; Meysman, M; Herreweghe, R V; Vincken, W

2000-12-01

Following airway stenting, bacterial colonization of the airways with potentially pathogenic micro-organisms occurs within 4 weeks after treatment in the majority of patients. The objective of this study was to prospectively investigate whether nonstenting therapeutic rigid bronchoscopy (using laser, cryotherapy, mechanical dilatation or debridement) is followed by airway colonization or infection. Protected specimen brush sampling of the central airways and quantitative culture were performed immediately prior to, and 4 weeks after nonstenting therapeutic rigid bronchoscopy in 20 consecutive patients with central airway lesions. Prior to therapeutic bronchoscopy, airway colonization/infection was present in nine of 20 (45%) patients. In these nine patients, 10 different potential pathogens were identified: Streptococcus pneumoniae (four cases), Pseudomonas aeruginosa (three), Haemophilus influenzae (two), and Serratia marcescens (one). Eight of these nine patients had a history of postobstructive infections, of which three were currently being treated with antibiotics. Four weeks following therapeutic bronchoscopy, airway colonization/infection was present in five of 20 (25%) patients, each of whom had airway colonization/infection prior to bronchoscopy. In three of these five patients, the same organisms were found 4 weeks after bronchoscopy as at baseline bronchoscopy. In two of five patients new organisms were identified: one case of Streptococcus viridans and one case of Haemophilus parainfluenzae, both considered to be nonpathogens. In four of nine patients with airway colonization/infection prior to bronchoscopy, the airways were clear of micro-organisms after the procedure. The authors conclude that: 1) nonstenting therapeutic rigid bronchoscopy is not complicated by airway colonization or infection by new potential pathogens; and 2) therapeutic rigid bronchoscopy led to clearing of airway colonization/infection in almost half of the patients studied.

Primary colonic well-differentiated / dedifferentiated liposarcoma of the ascending colon: a case report.

PubMed

Sawayama, Hiroshi; Yoshida, Naoya; Miyamoto, Yuji; Uchihara, Tomoyuki; Toihata, Tasuku; Yagi, Taisuke; Hiyoshi, Yukiharu; Iwatsuki, Masaaki; Baba, Yoshifumi; Baba, Hideo

2017-08-30

Primary colonic and dedifferentiated liposarcomas are both remarkably rare. This work describes a case of primary colonic well-differentiated/dedifferentiated liposarcoma and reviews the clinical characteristics and current therapies for liposarcoma tumors. A 52-year-old woman was referred to our hospital with a submucosal tumor of the ascending colon. Clinical analysis by ultrasound colonoscopy and computed tomography revealed a partially ossified tumor with irregular edges continuous with the muscular layer. High F-18 deoxyglucose uptake was detected by positron emission tomography. Radical resection with lymph node dissection was performed, yielding a tumor specimen approximately 6.5 × 4.0 × 3.2 cm. Neoplastic spindle cell proliferation was found from submucosa to subserosa. Well-differentiated adipose tissue surrounded the tumor, but contained atypical nuclei with condensed chromosomes. Immunohistochemical staining was positive for p16, CDK4, and MDM2 expression. Based on these findings, a diagnosis of well-differentiated/dedifferentiated liposarcoma was given. Dedifferentiated liposarcomas are more aggressive than their well-differentiated, low-grade counterparts. While local recurrence can occur with both tumor types, dedifferentiated liposarcomas are more prone to developing distant metastases. The patient received no postoperative therapy, and no recurrences have been observed 12 months after surgery. Here we report an extremely rare case of well-differentiated/dedifferentiated liposarcoma of the ascending colon. The dedifferentiated component was high-grade liposarcoma and well-differentiated liposarcoma was detected around the main tumor.

Identical bacterial populations colonize premature infant gut, skin, and oral microbiomes and exhibit different in situ growth rates

PubMed Central

Olm, Matthew R.; Brown, Christopher T.; Brooks, Brandon; Firek, Brian; Baker, Robyn; Burstein, David; Soenjoyo, Karina; Thomas, Brian C.; Morowitz, Michael; Banfield, Jillian F.

2017-01-01

The initial microbiome impacts the health and future development of premature infants. Methodological limitations have led to gaps in our understanding of the habitat range and subpopulation complexity of founding strains, as well as how different body sites support microbial growth. Here, we used metagenomics to reconstruct genomes of strains that colonized the skin, mouth, and gut of two hospitalized premature infants during the first month of life. Seven bacterial populations, considered to be identical given whole-genome average nucleotide identity of >99.9%, colonized multiple body sites, yet none were shared between infants. Gut-associated Citrobacter koseri genomes harbored 47 polymorphic sites that we used to define 10 subpopulations, one of which appeared in the gut after 1 wk but did not spread to other body sites. Differential genome coverage was used to measure bacterial population replication rates in situ. In all cases where the same bacterial population was detected in multiple body sites, replication rates were faster in mouth and skin compared to the gut. The ability of identical strains to colonize multiple body sites underscores the habit flexibility of initial colonists, whereas differences in microbial replication rates between body sites suggest differences in host control and/or resource availability. Population genomic analyses revealed microdiversity within bacterial populations, implying initial inoculation by multiple individual cells with distinct genotypes. Overall, however, the overlap of strains across body sites implies that the premature infant microbiome can exhibit very low microbial diversity. PMID:28073918

Topical Antimicrobial Treatments Can Elicit Shifts to Resident Skin Bacterial Communities and Reduce Colonization by Staphylococcus aureus Competitors

PubMed Central

SanMiguel, Adam J.; Meisel, Jacquelyn S.; Horwinski, Joseph; Zheng, Qi

2017-01-01

ABSTRACT The skin microbiome is a complex ecosystem with important implications for cutaneous health and disease. Topical antibiotics and antiseptics are often employed to preserve the balance of this population and inhibit colonization by more pathogenic bacteria. However, despite their widespread use, the impact of these interventions on broader microbial communities remains poorly understood. Here, we report the longitudinal effects of topical antibiotics and antiseptics on skin bacterial communities and their role in Staphylococcus aureus colonization resistance. In response to antibiotics, cutaneous populations exhibited an immediate shift in bacterial residents, an effect that persisted for multiple days posttreatment. By contrast, antiseptics elicited only minor changes to skin bacterial populations, with few changes to the underlying microbiota. While variable in scope, both antibiotics and antiseptics were found to decrease colonization by commensal Staphylococcus spp. by sequencing- and culture-based methods, an effect which was highly dependent on baseline levels of Staphylococcus. Because Staphylococcus residents have been shown to compete with the skin pathogen S. aureus, we also tested whether treatment could influence S. aureus levels at the skin surface. We found that treated mice were more susceptible to exogenous association with S. aureus and that precolonization with the same Staphylococcus residents that were previously disrupted by treatment reduced S. aureus levels by over 100-fold. In all, the results of this study indicate that antimicrobial drugs can alter skin bacterial residents and that these alterations can have critical implications for cutaneous host defense. PMID:28630195

Performance of primary repair on colon injuries sustained from low-versus high-energy projectiles

PubMed Central

Lazovic, Ranko; Radojevic, Nemanja; Curovic, Ivana

2017-01-01

Among various reasons, colon injuries may be caused by low- or high-energy firearm bullets, with the latter producing a temporary cavitation phenomenon. The available treatment options include primary repair and two-stage management, but recent studies have shown that primary repair can be widely used with a high success rate. This paper investigates the differences in performance of primary repair on these two types of colon injuries. Two groups of patients who sustained colon injuries due to single gunshot wounds, were retrospectively categorized based on the type of bullet. Primary colon repair was performed in all patients selected based on the inclusion and exclusion criteria (Stone and Fabian's criteria). An almost absolute homogeneity was attained among the groups in terms of age, latent time before surgery, and four trauma indexes. Only one patient from the low-energy firearm projectile group (4%) developed a postsurgical complication versus nine patients (25.8%) from the high-energy group, showing statistically significant difference (p = 0.03). These nine patients experienced the following postsurgical complications: pneumonia, abscess, fistula, suture leakage, and one multiorgan failure with sepsis. Previous studies concluded that one-stage primary repair is the best treatment option for colon injuries. However, terminal ballistics testing determined the projectile's path through the body and revealed that low-energy projectiles caused considerably lesser damage than their high-energy counterparts. Primary colon repair must be performed definitely for low-energy short firearm injuries but very carefully for high-energy injuries. Given these findings, we suggest that the treatment option should be determined based not only on the bullet type alone but also on other clinical findings. PMID:26874437

Can a new antiseptic agent reduce the bacterial colonization rate of central venous lines in post-cardiac surgery patients?

PubMed

Yousefshahi, Fardin; Azimpour, Khashayar; Boroumand, Mohammad Ali; Najafi, Mahdi; Barkhordari, Khosro; Vaezi, Mitra; Rouhipour, Nahid

2013-04-01

Central venous (CV) catheters play an essential role in the management of critically ill patients in the Intensive Care Unit (ICU). CV lines are, however, allied to catheter-associated blood stream infections. Bacterial colonization of CV lines is deemed the main cause of catheter-associated infection. The purpose of our study was to compare bacterial colony counts in the catheter site before CV line insertion in two groups of post-cardiac surgery patients: a group receiving Sanosil (an antiseptic agent composed of H2O2 and silver) and a control group. This interventional prospective double-blinded clinical trial recruited the patients in three post-cardiac surgery ICUs of a heart center. The participants were divided into interventional (113 patients) and control (136 patients) groups. Sanosil was added to the routine preparation procedure (Chlorhexidine bath one day before and scrub with Povidone-Iodine just before the CV line insertion). After the removal of the CV lines, the catheters tips were sent for culture and evaluation of colony counts. Catheter colonization occurred in 55 (22.1%) patients: 26 (23%) patients in the Sanosil group and 29 (21.3%) in the control group; there was no significant statistical difference between the two groups (p value = 0.75, RR = 1.05, 95% CI: 0.76-1.45). The most common organism having colonized in the cultures of the catheter tips was staphylococcus epidermis: 20 cases in the control group and 16 cases in the intervention group. Catheter colonization frequently occurs in post-cardiac surgery patients. However, our results did not indicate the effectiveness of adding Sanosil to the routine preparation procedure with respect to reducing catheter bacterial colonization.

Metastatic Male Ductal Breast Cancer Mimicking Obstructing Primary Colon Cancer

PubMed Central

Koleilat, Issam; Syal, Anil; Hena, Muhammad

2010-01-01

Male breast cancer comprises only about 1% of all breast cancers. Commonly, sites of metastases include the central nervous system, lungs, bones, and even liver. In females, extrahepatic gastrointestinal metastases are unusual but have been reported with various clinical presentations. We are reporting the first case of a male patient with a history of ductal breast carcinoma that developed colonic metastasis and presented with mechanical large bowel obstruction masquerading as primary colon cancer. PMID:23675178

Performance of primary repair on colon injuries sustained from low-versus high-energy projectiles.

PubMed

Lazovic, Ranko; Radojevic, Nemanja; Curovic, Ivana

2016-04-01

Among various reasons, colon injuries may be caused by low- or high-energy firearm bullets, with the latter producing a temporary cavitation phenomenon. The available treatment options include primary repair and two-stage management, but recent studies have shown that primary repair can be widely used with a high success rate. This paper investigates the differences in performance of primary repair on these two types of colon injuries. Two groups of patients who sustained colon injuries due to single gunshot wounds, were retrospectively categorized based on the type of bullet. Primary colon repair was performed in all patients selected based on the inclusion and exclusion criteria (Stone and Fabian's criteria). An almost absolute homogeneity was attained among the groups in terms of age, latent time before surgery, and four trauma indexes. Only one patient from the low-energy firearm projectile group (4%) developed a postsurgical complication versus nine patients (25.8%) from the high-energy group, showing statistically significant difference (p = 0.03). These nine patients experienced the following postsurgical complications: pneumonia, abscess, fistula, suture leakage, and one multiorgan failure with sepsis. Previous studies concluded that one-stage primary repair is the best treatment option for colon injuries. However, terminal ballistics testing determined the projectile's path through the body and revealed that low-energy projectiles caused considerably lesser damage than their high-energy counterparts. Primary colon repair must be performed definitely for low-energy short firearm injuries but very carefully for high-energy injuries. Given these findings, we suggest that the treatment option should be determined based not only on the bullet type alone but also on other clinical findings. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Function and Phylogeny of Bacterial Butyryl Coenzyme A:Acetate Transferases and Their Diversity in the Proximal Colon of Swine.

PubMed

Trachsel, Julian; Bayles, Darrell O; Looft, Torey; Levine, Uri Y; Allen, Heather K

2016-11-15

Studying the host-associated butyrate-producing bacterial community is important, because butyrate is essential for colonic homeostasis and gut health. Previous research has identified the butyryl coenzyme A (CoA):acetate-CoA transferase (EC 2.3.8.3) as a gene of primary importance for butyrate production in intestinal ecosystems; however, this gene family (but) remains poorly defined. We developed tools for the analysis of butyrate-producing bacteria based on 12 putative but genes identified in the genomes of nine butyrate-producing bacteria obtained from the swine intestinal tract. Functional analyses revealed that eight of these genes had strong But enzyme activity. When but paralogues were found within a genome, only one gene per genome encoded strong activity, with the exception of one strain in which no gene encoded strong But activity. Degenerate primers were designed to amplify the functional but genes and were tested by amplifying environmental but sequences from DNA and RNA extracted from swine colonic contents. The results show diverse but sequences from swine-associated butyrate-producing bacteria, most of which clustered near functionally confirmed sequences. Here, we describe tools and a framework that allow the bacterial butyrate-producing community to be profiled in the context of animal health and disease. Butyrate is a compound produced by the microbiota in the intestinal tracts of animals. This compound is of critical importance for intestinal health, and yet studying its production by diverse intestinal bacteria is technically challenging. Here, we present an additional way to study the butyrate-producing community of bacteria using one degenerate primer set that selectively targets genes experimentally demonstrated to encode butyrate production. This work will enable researchers to more easily study this very important bacterial function that has implications for host health and resistance to disease. Copyright © 2016, American Society for

Copper Is a Host Effector Mobilized to Urine during Urinary Tract Infection To Impair Bacterial Colonization

PubMed Central

Hyre, Amanda N.; Kavanagh, Kylie; Kock, Nancy D.; Donati, George L.

2016-01-01

ABSTRACT Urinary tract infection (UTI) is a major global infectious disease affecting millions of people annually. Human urinary copper (Cu) content is elevated during UTI caused by uropathogenic Escherichia coli (UPEC). UPEC upregulates the expression of Cu efflux genes during clinical UTI in patients as an adaptive response to host-derived Cu. Whether Cu is mobilized to urine as a host response to UTI and its role in protection against UTI remain unresolved. To address these questions, we tested the hypothesis that Cu is a host effector mobilized to urine during UTI to limit bacterial growth. Our results reveal that Cu is mobilized to urine during UTI caused by the major uropathogens Proteus mirabilis and Klebsiella pneumoniae, in addition to UPEC, in humans. Ceruloplasmin, a Cu-containing ferroxidase, is found at higher levels in UTI urine than in healthy control urine and serves as the molecular source of urinary Cu during UTI. Our results demonstrate that ceruloplasmin decreases the bioavailability of iron in urine by a transferrin-dependent mechanism. Experimental UTI with UPEC in nonhuman primates recapitulates the increased urinary Cu content observed during clinical UTI. Furthermore, Cu-deficient mice are highly colonized by UPEC, indicating that Cu is involved in the limiting of bacterial growth within the urinary tract. Collectively, our results indicate that Cu is a host effector that is involved in protection against pathogen colonization of the urinary tract. Because urinary Cu levels are amenable to modulation, augmentation of the Cu-based host defense against UTI represents a novel approach to limiting bacterial colonization during UTI. PMID:28031261

Topical Antimicrobial Treatments Can Elicit Shifts to Resident Skin Bacterial Communities and Reduce Colonization by Staphylococcus aureus Competitors.

PubMed

SanMiguel, Adam J; Meisel, Jacquelyn S; Horwinski, Joseph; Zheng, Qi; Grice, Elizabeth A

2017-09-01

The skin microbiome is a complex ecosystem with important implications for cutaneous health and disease. Topical antibiotics and antiseptics are often employed to preserve the balance of this population and inhibit colonization by more pathogenic bacteria. However, despite their widespread use, the impact of these interventions on broader microbial communities remains poorly understood. Here, we report the longitudinal effects of topical antibiotics and antiseptics on skin bacterial communities and their role in Staphylococcus aureus colonization resistance. In response to antibiotics, cutaneous populations exhibited an immediate shift in bacterial residents, an effect that persisted for multiple days posttreatment. By contrast, antiseptics elicited only minor changes to skin bacterial populations, with few changes to the underlying microbiota. While variable in scope, both antibiotics and antiseptics were found to decrease colonization by commensal Staphylococcus spp. by sequencing- and culture-based methods, an effect which was highly dependent on baseline levels of Staphylococcus Because Staphylococcus residents have been shown to compete with the skin pathogen S. aureus , we also tested whether treatment could influence S. aureus levels at the skin surface. We found that treated mice were more susceptible to exogenous association with S. aureus and that precolonization with the same Staphylococcus residents that were previously disrupted by treatment reduced S. aureus levels by over 100-fold. In all, the results of this study indicate that antimicrobial drugs can alter skin bacterial residents and that these alterations can have critical implications for cutaneous host defense. Copyright © 2017 American Society for Microbiology.

Bacterial Colonization of Pellet Softening Reactors Used during Drinking Water Treatment▿

PubMed Central

Hammes, Frederik; Boon, Nico; Vital, Marius; Ross, Petra; Magic-Knezev, Aleksandra; Dignum, Marco

2011-01-01

Pellet softening reactors are used in centralized and decentralized drinking water treatment plants for the removal of calcium (hardness) through chemically induced precipitation of calcite. This is accomplished in fluidized pellet reactors, where a strong base is added to the influent to increase the pH and facilitate the process of precipitation on an added seeding material. Here we describe for the first time the opportunistic bacterial colonization of the calcite pellets in a full-scale pellet softening reactor and the functional contribution of these colonizing bacteria to the overall drinking water treatment process. ATP analysis, advanced microscopy, and community fingerprinting with denaturing gradient gel electrophoretic (DGGE) analysis were used to characterize the biomass on the pellets, while assimilable organic carbon (AOC), dissolved organic carbon, and flow cytometric analysis were used to characterize the impact of the biological processes on drinking water quality. The data revealed pellet colonization at concentrations in excess of 500 ng of ATP/g of pellet and reactor biomass concentrations as high as 220 mg of ATP/m3 of reactor, comprising a wide variety of different microorganisms. These organisms removed as much as 60% of AOC from the water during treatment, thus contributing toward the biological stabilization of the drinking water. Notably, only a small fraction (about 60,000 cells/ml) of the bacteria in the reactors was released into the effluent under normal conditions, while the majority of the bacteria colonizing the pellets were captured in the calcite structures of the pellets and were removed as a reusable product. PMID:21148700

Bacterial colonization of pellet softening reactors used during drinking water treatment.

PubMed

Hammes, Frederik; Boon, Nico; Vital, Marius; Ross, Petra; Magic-Knezev, Aleksandra; Dignum, Marco

2011-02-01

Pellet softening reactors are used in centralized and decentralized drinking water treatment plants for the removal of calcium (hardness) through chemically induced precipitation of calcite. This is accomplished in fluidized pellet reactors, where a strong base is added to the influent to increase the pH and facilitate the process of precipitation on an added seeding material. Here we describe for the first time the opportunistic bacterial colonization of the calcite pellets in a full-scale pellet softening reactor and the functional contribution of these colonizing bacteria to the overall drinking water treatment process. ATP analysis, advanced microscopy, and community fingerprinting with denaturing gradient gel electrophoretic (DGGE) analysis were used to characterize the biomass on the pellets, while assimilable organic carbon (AOC), dissolved organic carbon, and flow cytometric analysis were used to characterize the impact of the biological processes on drinking water quality. The data revealed pellet colonization at concentrations in excess of 500 ng of ATP/g of pellet and reactor biomass concentrations as high as 220 mg of ATP/m(3) of reactor, comprising a wide variety of different microorganisms. These organisms removed as much as 60% of AOC from the water during treatment, thus contributing toward the biological stabilization of the drinking water. Notably, only a small fraction (about 60,000 cells/ml) of the bacteria in the reactors was released into the effluent under normal conditions, while the majority of the bacteria colonizing the pellets were captured in the calcite structures of the pellets and were removed as a reusable product.

Can a New Antiseptic Agent Reduce the Bacterial Colonization Rate of Central Venous Lines in Post-Cardiac Surgery Patients?

PubMed Central

Yousefshahi, Fardin; Azimpour, Khashayar; Boroumand, Mohammad Ali; Najafi, Mahdi; Barkhordari, Khosro; Vaezi, Mitra; Rouhipour, Nahid

2013-01-01

Background: Central venous (CV) catheters play an essential role in the management of critically ill patients in the Intensive Care Unit (ICU). CV lines are, however, allied to catheter-associated blood stream infections. Bacterial colonization of CV lines is deemed the main cause of catheter-associated infection. The purpose of our study was to compare bacterial colony counts in the catheter site before CV line insertion in two groups of post-cardiac surgery patients: a group receiving Sanosil (an antiseptic agent composed of H2O2 and silver) and a control group. Methods: This interventional prospective double-blinded clinical trial recruited the patients in three post-cardiac surgery ICUs of a heart center. The participants were divided into interventional (113 patients) and control (136 patients) groups. Sanosil was added to the routine preparation procedure (Chlorhexidine bath one day before and scrub with Povidone-Iodine just before the CV line insertion). After the removal of the CV lines, the catheters tips were sent for culture and evaluation of colony counts. Results: Catheter colonization occurred in 55 (22.1%) patients: 26 (23%) patients in the Sanosil group and 29 (21.3%) in the control group; there was no significant statistical difference between the two groups (p value = 0.75, RR = 1.05, 95% CI: 0.76–1.45). The most common organism having colonized in the cultures of the catheter tips was staphylococcus epidermis: 20 cases in the control group and 16 cases in the intervention group. Conclusion: Catheter colonization frequently occurs in post-cardiac surgery patients. However, our results did not indicate the effectiveness of adding Sanosil to the routine preparation procedure with respect to reducing catheter bacterial colonization. PMID:23967028

The effect of a probiotic drink with Lactobacillus plantarum 299v on the bacterial composition in faeces and mucosal biopsies of rectum and ascending colon.

PubMed

Goossens, D A M; Jonkers, D M A E; Russel, M G V M; Stobberingh, E E; Stockbrügger, R W

2006-01-15

Studies on probiotics mainly base their results on faecal samples, which may not represent the situation in the mucosa of distal and proximal colon. In a placebo-controlled study, to assess the effect of Lactobacillus plantarum 299v on the bacterial composition of faecal vs. mucosal samples. Twenty-nine patients undergoing colonoscopic examination for polyps consumed a twice-daily drink with or without L. plantarum 299v (10(11) CFU/day) for 2 weeks. Faecal samples were collected before and after consumption. During colonoscopy, biopsies were collected from the ascending colon and rectum. The faecal and mucosal bacterial concentrations and prevalence were determined. L. plantarum 299v significantly increased the concentration of faecal lactic acid bacteria, lactobacilli and clostridia, and was identified in two rectal biopsies but not in the ascending colon biopsies of probiotic-treated subjects. Concentrations and prevalence in ascending colon and rectum biopsies were comparable, but were significantly lower compared with faecal samples. After probiotic consumption, a significant increase in the faecal concentration of lactobacilli was found but concentrations were low in biopsies. The bacterial composition in biopsies of the ascending colon and rectum did not differ based on culture techniques. To further elucidate the modes of action of probiotics, it might be necessary to study differences in colonization with molecular techniques.

[Primary colonic intussusception protruding from the anus in adults. Two cases].

PubMed

Bail, J P; Holderbach, L J; Robaszkiewicz, M; Dartoy, C; Noundou, P M; Charles, J F

1992-01-01

The authors report two cases of colonic intussusception in the adult protruding from the anus--or colon-anal intussusception--, not due to a tumor. The first case was a chronic ileo-caeco-colique intussusception, the second case was an acute colo-rectal intussusception. Colo-anal intussusceptions are very rare: less than twenty cases have been described since 1925 in adults. The absence of a tumor origin in our cases represents a special feature, as only three other similar cases have been described. The surgical treatment in both cases was primary colonic resection without colostomy. The surgical treatment of the first case was subtotal colectomy with ileo-rectal anastomosis. The second case was primarily reduced by barium enema which allowed optimal secondary surgical resection of a prepared colon.

Copper Is a Host Effector Mobilized to Urine during Urinary Tract Infection To Impair Bacterial Colonization.

PubMed

Hyre, Amanda N; Kavanagh, Kylie; Kock, Nancy D; Donati, George L; Subashchandrabose, Sargurunathan

2017-03-01

Urinary tract infection (UTI) is a major global infectious disease affecting millions of people annually. Human urinary copper (Cu) content is elevated during UTI caused by uropathogenic Escherichia coli (UPEC). UPEC upregulates the expression of Cu efflux genes during clinical UTI in patients as an adaptive response to host-derived Cu. Whether Cu is mobilized to urine as a host response to UTI and its role in protection against UTI remain unresolved. To address these questions, we tested the hypothesis that Cu is a host effector mobilized to urine during UTI to limit bacterial growth. Our results reveal that Cu is mobilized to urine during UTI caused by the major uropathogens Proteus mirabilis and Klebsiella pneumoniae , in addition to UPEC, in humans. Ceruloplasmin, a Cu-containing ferroxidase, is found at higher levels in UTI urine than in healthy control urine and serves as the molecular source of urinary Cu during UTI. Our results demonstrate that ceruloplasmin decreases the bioavailability of iron in urine by a transferrin-dependent mechanism. Experimental UTI with UPEC in nonhuman primates recapitulates the increased urinary Cu content observed during clinical UTI. Furthermore, Cu-deficient mice are highly colonized by UPEC, indicating that Cu is involved in the limiting of bacterial growth within the urinary tract. Collectively, our results indicate that Cu is a host effector that is involved in protection against pathogen colonization of the urinary tract. Because urinary Cu levels are amenable to modulation, augmentation of the Cu-based host defense against UTI represents a novel approach to limiting bacterial colonization during UTI. Copyright © 2017 American Society for Microbiology.

Colonization of Vitis vinifera by a Green Fluorescence Protein-Labeled, gfp-Marked Strain of Xylophilus ampelinus, the Causal Agent of Bacterial Necrosis of Grapevine

PubMed Central

Grall, Sophie; Manceau, Charles

2003-01-01

The dynamics of Xylophilus ampelinus were studied in Vitis vinifera cv. Ugni blanc using gfp-marked bacterial strains to evaluate the relative importance of epiphytic and endophytic phases of plant colonization in disease development. Currently, bacterial necrosis of grapevine is of economic importance in vineyards in three regions in France: the Cognac, Armagnac, and Die areas. This disease is responsible for progressive destruction of vine shoots, leading to their death. We constructed gfp-marked strains of the CFBP2098 strain of X. ampelinus for histological studies. We studied the colonization of young plants of V. vinifera cv. Ugni blanc by X. ampelinus after three types of artificial contamination in a growth chamber and in a greenhouse. (i) After wounding of the stem and inoculation, the bacteria progressed down to the crown through the xylem vessels, where they organized into biofilms. (ii) When the bacteria were forced into woody cuttings, they rarely colonized the emerging plantlets. Xylem vessels could play a key role in the multiplication and conservation of the bacteria, rather than being a route for plant colonization. (iii) When bacterial suspensions were sprayed onto the plants, bacteria progressed in two directions: both in emerging organs and down to the crown, thus displaying the importance of epiphytic colonization in disease development. PMID:12676663

Colonization of Vitis vinifera by a green fluorescence protein-labeled, gfp-marked strain of Xylophilus ampelinus, the causal agent of bacterial necrosis of grapevine.

PubMed

Grall, Sophie; Manceau, Charles

2003-04-01

The dynamics of Xylophilus ampelinus were studied in Vitis vinifera cv. Ugni blanc using gfp-marked bacterial strains to evaluate the relative importance of epiphytic and endophytic phases of plant colonization in disease development. Currently, bacterial necrosis of grapevine is of economic importance in vineyards in three regions in France: the Cognac, Armagnac, and Die areas. This disease is responsible for progressive destruction of vine shoots, leading to their death. We constructed gfp-marked strains of the CFBP2098 strain of X. ampelinus for histological studies. We studied the colonization of young plants of V. vinifera cv. Ugni blanc by X. ampelinus after three types of artificial contamination in a growth chamber and in a greenhouse. (i) After wounding of the stem and inoculation, the bacteria progressed down to the crown through the xylem vessels, where they organized into biofilms. (ii) When the bacteria were forced into woody cuttings, they rarely colonized the emerging plantlets. Xylem vessels could play a key role in the multiplication and conservation of the bacteria, rather than being a route for plant colonization. (iii) When bacterial suspensions were sprayed onto the plants, bacteria progressed in two directions: both in emerging organs and down to the crown, thus displaying the importance of epiphytic colonization in disease development.

Bacterial colonization of penile prosthesis after its withdrawal due to mechanical failure.

PubMed

Etcheverry-Giadrosich, B; Torremadé-Barreda, J; Pujol-Galarza, L; Vigués-Julià, F

2017-12-01

Prosthetic surgery to treat erectile dysfunction has a risk of infection of up to 3%, but this risk can increase to 18% when the surgery involves replacement. This increased risk of infection is attributed to the bacterial colonization of the prosthesis during the initial surgery. To analyse the presence of germs in the prosthesis that is withdrawn due to mechanical failure (not infection), as well as the surgical results and its progression. A retrospective study was conducted of all replacements performed between 2013 and 2016 at a single centre. We analysed demographic data, prior type of prosthesis, surgical procedure, microbiological study and follow-up. Of the 12 replacement procedures, a microbiological study of the extracted prosthesis was performed in a total of 10 cases. Of the 10 replacements, the cultures were positive in 5 cases (50%). Staphylococcus epidermidis was the most prevalent germ. All patients underwent a flushing procedure, and an antibiotic-coated prosthesis was implanted. We recorded no infections with the new implanted device after a mean follow-up of 27.33 months (SD 4.13; 95% CI 18.22-36.43). In our study population, we observed a high rate of bacterial colonization of the prostheses that were replaced due to mechanical failure. When a flushing procedure was performed during the replacement surgery, there were no more infections than those reported in treatment-naive cases. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

SIGIRR, a negative regulator of TLR/IL-1R signalling promotes Microbiota dependent resistance to colonization by enteric bacterial pathogens.

PubMed

Sham, Ho Pan; Yu, Emily Yi Shan; Gulen, Muhammet F; Bhinder, Ganive; Stahl, Martin; Chan, Justin M; Brewster, Lara; Morampudi, Vijay; Gibson, Deanna L; Hughes, Michael R; McNagny, Kelly M; Li, Xiaoxia; Vallance, Bruce A

2013-01-01

Enteric bacterial pathogens such as enterohemorrhagic E. coli (EHEC) and Salmonella Typhimurium target the intestinal epithelial cells (IEC) lining the mammalian gastrointestinal tract. Despite expressing innate Toll-like receptors (TLRs), IEC are innately hypo-responsive to most bacterial products. This is thought to prevent maladaptive inflammatory responses against commensal bacteria, but it also limits antimicrobial responses by IEC to invading bacterial pathogens, potentially increasing host susceptibility to infection. One reason for the innate hypo-responsiveness of IEC is their expression of Single Ig IL-1 Related Receptor (SIGIRR), a negative regulator of interleukin (IL)-1 and TLR signaling. To address whether SIGIRR expression and the innate hypo-responsiveness of IEC impacts on enteric host defense, Sigirr deficient (-/-) mice were infected with the EHEC related pathogen Citrobacter rodentium. Sigirr -/- mice responded with accelerated IEC proliferation and strong pro-inflammatory and antimicrobial responses but surprisingly, Sigirr -/- mice proved dramatically more susceptible to infection than wildtype mice. Through haematopoietic transplantation studies, it was determined that SIGIRR expression by non-haematopoietic cells (putative IEC) regulated these responses. Moreover, the exaggerated responses were found to be primarily dependent on IL-1R signaling. Whilst exploring the basis for their susceptibility, Sigirr -/- mice were found to be unusually susceptible to intestinal Salmonella Typhimurium colonization, developing enterocolitis without the typical requirement for antibiotic based removal of competing commensal microbes. Strikingly, the exaggerated antimicrobial responses seen in Sigirr -/- mice were found to cause a rapid and dramatic loss of commensal microbes from the infected intestine. This depletion appears to reduce the ability of the microbiota to compete for space and nutrients (colonization resistance) with the invading pathogens

Pattern of tumour growth of the primary colon cancer predicts long-term outcome after resection of liver metastases.

PubMed

Spelt, Lidewij; Sasor, Agata; Ansari, Daniel; Andersson, Roland

2016-10-01

To identify significant predictive factors for overall survival (OS) and disease-free survival (DFS) after liver resection for colon cancer metastases, with special focus on features of the primary colon cancer, such as lymph node ratio (LNR), vascular invasion, and perineural invasion. Patients operated for colonic cancer liver metastases between 2006 and 2014 were included. Details on patient characteristics, the primary colon cancer operation and metastatic disease were collected. Multivariate analysis was performed to select predictive variables for OS and DFS. Median OS and DFS were 67 and 20 months, respectively. 1-, 3- and 5-year OS were 97, 76, and 52%. 1-, 3- and 5-year DFS were 65, 42, and 37%. Multivariate analysis showed LNR to be an independent predictive factor for DFS but not for OS. Other identified predictive factors were vascular and perineural invasion of the primary colon cancer, size of the largest metastasis and severe complications after liver surgery for OS, and perineural invasion, number of liver metastases and preoperative CEA-level for DFS. Traditional N-stage was also considered to be an independent predictive factor for DFS in a separate multivariate analysis. LNR and perineural invasion of the primary colon cancer can be used as a prognostic variable for DFS after a concomitant liver resection for colon cancer metastases. Vascular and perineural invasion of the primary colon cancer are predictive for OS.

Computed tomography findings of ovarian metastases from colon cancer: comparison with primary malignant ovarian tumors.

PubMed

Choi, Hyuck Jae; Lee, Joo-Hyuk; Seo, Sang-Soo; Lee, Sun; Kim, Seok Ki; Kim, Joo-Young; Lee, Jong Seok; Park, Sang-Yoon; Kim, Young Hoon

2005-01-01

The computed tomography (CT) findings of ovarian metastases from colon cancer were evaluated and were compared with those of primary malignant ovarian tumors. Sixteen patients with 21 masses from colon cancer and 20 patients with 31 primary malignant ovarian tumors were included in this study. The CT findings (laterality, size, margin, shape, mass characteristic, strong enhancement of cyst wall, enhancement of solid portion, amount of ascites, peritoneal seeding, lymph node enlargement, and metastasis) and ages of the patients in both groups were compared. Univariate analysis, the Pearson chi test, and the independent-samples t test were used to distinguish them. A smooth margin of the tumor (odds ratio=24.3, 95% confidence interval: 2.9-204.2) and cystic nature of the mass (Pearson chi=12.96, P=0.005) were strong predictors of ovarian metastasis from colon cancer. Ovarian metastases from colon cancer show a smooth margin and more cystic nature on CT compared with primary malignant ovarian tumors.

Radioimmunoguided surgery in primary colon cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nieroda, C.A.; Mojzisik, C.; Sardi, A.

1990-01-01

Radioimmunoguided surgery (RIGS), the intraoperative use of a hand-held gamma detecting probe (GDP) to identify tissue containing radiolabeled monoclonal antibody (MAb), was performed upon 30 patients with primary colon carcinoma. Each patient received an intravenous injection of MAb B72.3 (1.0 to 0.25 mg) radiolabeled with {sup 125}I (5.0 to 1.0 mCi) 8 to 34 days before exploration. The GDP was used to measure radioactivity in colon tissue, tumor bed, nodal drainage areas, and areas of suspected metastases. Antibody localized to histologically documented tumor in 23 of 30 patients (77%). Tumor margins were more clearly defined in 20 of 30 patientsmore » (67%). GDP counts led to major alterations in surgical resection in five patients (17%) and changes in adjuvant therapy in four (14%). GDP counts identified occult liver metastases in two patients (7%) and correctly indicated the benign nature of liver masses in three (10%). In four patients (13%), occult nodal metastases were identified. RIGS can precisely delineate tumor margins, define the extent of nodal involvement, and localize occult tumor, providing a method of immediate intraoperative staging that may lessen recurrences and produce higher survival rates.« less

Copolymers enhance selective bacterial community colonization for potential root zone applications.

PubMed

Pham, Vy T H; Murugaraj, Pandiyan; Mathes, Falko; Tan, Boon K; Truong, Vi Khanh; Murphy, Daniel V; Mainwaring, David E

2017-11-21

Managing the impact of anthropogenic and climate induced stress on plant growth remains a challenge. Here we show that polymeric hydrogels, which maintain their hydrous state, can be designed to exploit functional interactions with soil microorganisms. This microbial enhancement may mitigate biotic and abiotic stresses limiting productivity. The presence of mannan chains within synthetic polyacrylic acid (PAA) enhanced the dynamics and selectivity of bacterial ingress in model microbial systems and soil microcosms. Pseudomonas fluorescens exhibiting high mannan binding adhesins showed higher ingress and localised microcolonies throughout the polymeric network. In contrast, ingress of Bacillus subtilis, lacking adhesins, was unaltered by mannan showing motility comparable to bulk liquids. Incubation within microcosms of an agricultural soil yielded hydrogel populations significantly increased from the corresponding soil. Bacterial diversity was markedly higher in mannan containing hydrogels compared to both control polymer and soil, indicating enhanced selectivity towards microbial families that contain plant beneficial species. Here we propose functional polymers applied to the potential root zone which can positively influence rhizobacteria colonization and potentially plant growth as a new approach to stress tolerance.

Systemic cytokine signaling via IL-17 in smokers with obstructive pulmonary disease: a link to bacterial colonization?

PubMed Central

Andelid, Kristina; Tengvall, Sara; Andersson, Anders; Levänen, Bettina; Christenson, Karin; Jirholt, Pernilla; Åhrén, Christina; Qvarfordt, Ingemar; Ekberg-Jansson, Ann; Lindén, Anders

2015-01-01

We examined whether systemic cytokine signaling via interleukin (IL)-17 and growth-related oncogene-α (GRO-α) is impaired in smokers with obstructive pulmonary disease including chronic bronchitis (OPD-CB). We also examined how this systemic cytokine signaling relates to bacterial colonization in the airways of the smokers with OPD-CB. Currently smoking OPD-CB patients (n=60, corresponding to Global initiative for chronic Obstructive Lung Disease [GOLD] stage I–IV) underwent recurrent blood and sputum sampling over 60 weeks, during stable conditions and at exacerbations. We characterized cytokine protein concentrations in blood and bacterial growth in sputum. Asymptomatic smokers (n=10) and never-smokers (n=10) were included as control groups. During stable clinical conditions, the protein concentrations of IL-17 and GRO-α were markedly lower among OPD-CB patients compared with never-smoker controls, whereas the asymptomatic smoker controls displayed intermediate concentrations. Notably, among OPD-CB patients, colonization by opportunistic pathogens was associated with markedly lower IL-17 and GRO-α, compared with colonization by common respiratory pathogens or oropharyngeal flora. During exacerbations in the OPD-CB patients, GRO-α and neutrophil concentrations were increased, whereas protein concentrations and messenger RNA for IL-17 were not detectable in a reproducible manner. In smokers with OPD-CB, systemic cytokine signaling via IL-17 and GRO-α is impaired and this alteration may be linked to colonization by opportunistic pathogens in the airways. Given the potential pathogenic and therapeutic implications, these findings deserve to be validated in new and larger patient cohorts. PMID:25848245

Use of portable electronic devices in a hospital setting and their potential for bacterial colonization.

PubMed

Khan, Amber; Rao, Amitha; Reyes-Sacin, Carlos; Hayakawa, Kayoko; Szpunar, Susan; Riederer, Kathleen; Kaye, Keith; Fishbain, Joel T; Levine, Diane

2015-03-01

Portable electronic devices are increasingly being used in the hospital setting. As with other fomites, these devices represent a potential reservoir for the transmission of pathogens. We conducted a convenience sampling of devices in 2 large medical centers to identify bacterial colonization rates and potential risk factors. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Indications for and outcome of primary repair compared with faecal diversion in the management of traumatic colon injury.

PubMed

Fouda, E; Emile, S; Elfeki, H; Youssef, M; Ghanem, A; Fikry, A A; Elshobaky, A; Omar, W; Khafagy, W; Morshed, M

2016-08-01

Injuries of the colon are a serious sequel of abdominal trauma owing to the associated morbidity and mortality. This study aims to assess postoperative outcome and complications of faecal diversion and primary repair of colon injuries when applied according to established guidelines for the management of colon injuries. This retrospective study was conducted on 110 patients with colon injuries. Guided by estimation of risk factors, patients were managed either by primary repair alone, repair with proximal diversion or diversion alone. There were 102 (92.7%) male patients and 8 (7.3%) female patients of median age 38 years. Thirty-seven were managed by primary repair and 73 by faecal diversion. Colon injuries were caused by penetrating abdominal trauma in 65 and blunt trauma in 45 patients. Forty-three patients were in shock on admission, and were all managed by faecal diversion. Forty patients developed 84 complications after surgery. Primary repair had a significantly lower complication rate than faecal diversion (P = 0.037). Wound infection was the commonest complication. The overall mortality rate was 3.6%. Primary repair, when employed properly, resulted in a significantly lower complication rate than faecal diversion. Significant predictive factors associated with a higher complication rate were faecal diversion, severe faecal contamination, multiple colon injuries, an interval of more than 12 h after colon injury and shock. Colorectal Disease © 2016 The Association of Coloproctology of Great Britain and Ireland.

Tolerance to oxidative stress is required for maximal xylem colonization by the xylem-limited bacterial phytopathogen, Xylella fastidiosa.

PubMed

Wang, Peng; Lee, Yunho; Igo, Michele M; Roper, M Caroline

2017-09-01

Bacterial plant pathogens often encounter reactive oxygen species (ROS) during host invasion. In foliar bacterial pathogens, multiple regulatory proteins are involved in the sensing of oxidative stress and the activation of the expression of antioxidant genes. However, it is unclear whether xylem-limited bacteria, such as Xylella fastidiosa, experience oxidative stress during the colonization of plants. Examination of the X. fastidiosa genome uncovered only one homologue of oxidative stress regulatory proteins, OxyR. Here, a knockout mutation in the X. fastidiosa oxyR gene was constructed; the resulting strain was significantly more sensitive to hydrogen peroxide (H 2 O 2 ) relative to the wild-type. In addition, during early stages of grapevine infection, the survival rate was 1000-fold lower for the oxyR mutant than for the wild-type. This supports the hypothesis that grapevine xylem represents an oxidative environment and that X. fastidiosa must overcome this challenge to achieve maximal xylem colonization. Finally, the oxyR mutant exhibited reduced surface attachment and cell-cell aggregation and was defective in biofilm maturation, suggesting that ROS could be a potential environmental cue stimulating biofilm development during the early stages of host colonization. © 2016 BSPP AND JOHN WILEY & SONS LTD.

Imaging Nuclear-Cytoplasmic Dynamics in Primary and Metastatic Colon Cancer in Nude Mice.

PubMed

Hasegawa, Kosuke; Suetsugu, Atsushi; Nakamura, Miki; Matsumoto, Takuro; Aoki, Hitomi; Kunisada, Takahiro; Bouvet, Michael; Shimizu, Masahito; Hoffman, Robert M

2016-05-01

Colon cancer frequently results in metastasis to the liver, where it becomes the main cause of death. However, the cell cycle in primary tumors and metastases is poorly understood. We developed a mouse model of liver metastasis using the human colon cancer cell line HCT-116, which expresses green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm (HCT-116-GFP-RFP). HCT-116 GFP-RFP cells were injected into the spleen of nu/nu nude mice. HCT-116-GFP-RFP cells subsequently formed primary tumors in the spleen, as well as metastatic colonies in the liver and retroperitoneum by 28 days after cell transplantation. Using an Olympus FV1000 confocal microscope, it was possible to clearly image mitosis of the dual-colored colon cancer cells in the primary tumor as well as liver and other metastases. Multi-nucleate cancer cells, in addition to mono-nucleate cancer cells and their mitosis, were observed in the primary tumor and metastasis. Multi-nucleate HCT-116-GFP-RFP cells were also observed after culture of the primary and metastatic tumors. A similar ratio of mono-nucleate, multi-nucleate, and mitotic cells grew from the primary and metastatic tumors in culture, suggesting similarity of the nuclear-cytoplasmic dynamics of primary and metastatic cancer cells, further emphasizing the stochastic nature of metastasis. Our results demonstrate a similar heterogeneity of nuclear-cytoplasmic dynamics within primary tumors and metastases, which may be an important factor in the stochastic nature of metastasis. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Randomized Controlled Trial to Reduce Bacterial Colonization of Surgical Drains After Breast and Axillary Operations

PubMed Central

Degnim, Amy C.; Scow, Jeffrey S.; Hoskin, Tanya L.; Miller, Joyce P.; Loprinzi, Margie; Boughey, Judy C.; Jakub, James W.; Throckmorton, Alyssa; Patel, Robin; Baddour, Larry M.

2014-01-01

Objective To determine if bacterial colonization of drains can be reduced by local antiseptic interventions. Summary Background Drains are a potential source of bacterial entry into surgical wounds and may contribute to surgical site infection (SSI) after breast surgery. Methods Following IRB approval, patients undergoing total mastectomy and/or axillary lymph node dissection were randomized to standard drain care (control) or drain antisepsis (treated). Standard drain care comprised twice daily cleansing with alcohol swabs. Antisepsis drain care included 1) a chlorhexidine disc at the drain exit site and 2) irrigation of the drain bulb twice daily with dilute sodium hypochlorite (Dakin’s) solution. Cultures results of drain fluid and tubing were compared between control and antisepsis groups. Results Overall, 100 patients with 125 drains completed the study with 48 patients (58 drains) in the control group and 52 patients (67 drains) in the antisepsis group. Cultures of drain bulb fluid at one week were positive (1+ or greater growth) in 66% (38/58) of control drains compared to 21% of antisepsis drains (14/67), (p=0.0001). Drain tubing cultures demonstrated >50 CFU in 19% (8/43) of control drains versus 0% (0/53) of treated drains (p=0.004). SSI was diagnosed in 6 patients (6%) - 5 patients in the control group and 1 patient in the antisepsis group (p=0.06). Conclusions Simple and inexpensive local antiseptic interventions with a chlorhexidine disc and hypochlorite solution reduce bacterial colonization of drains. Based on these data, further study of drain antisepsis and its potential impact on SSI rate is warranted. PMID:23518704

Association of bacterial colonization at the time of presentation to a combat support hospital in a combat zone with subsequent 30-day colonization or infection.

PubMed

Kaspar, Robert L; Griffith, Matthew E; Mann, Paul B; Lehman, Devon J; Conger, Nicholas G; Hospenthal, Duane R; Murray, Clinton K

2009-09-01

U.S. casualties have developed multidrug-resistant (MDR) bacterial infections. A surveillance project to evaluate U.S. military patients for the presence of MDR pathogens from wounding through the first 30 days of care in the military healthcare system (MHS) was performed. U.S. military patients admitted to a single combat support hospital in Iraq during June-July of 2007 had screening swabs obtained for the detection of MDR bacteria and a subsequent retrospective electronic medical records review for presence of colonization or infection in the subsequent 30 days. Screening of 74 U.S. military patients in Iraq found one colonized with methicillin-resistant Staphylococcus aureus. Fifty-six patients of these were screened for Acinetobacter in Germany and one found colonized. Of patients evacuated to the U.S., 9 developed infections. Carefully obtained screening cultures immediately after injury combined with look-back monitoring supports the role of nosocomial transmission. Consistent infection control strategies are needed for the entire MHS.

Effect of flow and peristaltic mixing on bacterial growth in a gut-like channel

PubMed Central

Cremer, Jonas; Segota, Igor; Yang, Chih-yu; Arnoldini, Markus; Sauls, John T.; Zhang, Zhongge; Gutierrez, Edgar; Groisman, Alex; Hwa, Terence

2016-01-01

The ecology of microbes in the gut has been shown to play important roles in the health of the host. To better understand microbial growth and population dynamics in the proximal colon, the primary region of bacterial growth in the gut, we built and applied a fluidic channel that we call the “minigut.” This is a channel with an array of membrane valves along its length, which allows mimicking active contractions of the colonic wall. Repeated contraction is shown to be crucial in maintaining a steady-state bacterial population in the device despite strong flow along the channel that would otherwise cause bacterial washout. Depending on the flow rate and the frequency of contractions, the bacterial density profile exhibits varying spatial dependencies. For a synthetic cross-feeding community, the species abundance ratio is also strongly affected by mixing and flow along the length of the device. Complex mixing dynamics due to contractions is described well by an effective diffusion term. Bacterial dynamics is captured by a simple reaction–diffusion model without adjustable parameters. Our results suggest that flow and mixing play a major role in shaping the microbiota of the colon. PMID:27681630

Biliary Endoprosthesis: A Prospective Analysis of Bacterial Colonization and Risk Factors for Sludge Formation

PubMed Central

Schneider, Jochen; Hapfelmeier, Alexander; Fremd, Julia; Schenk, Philipp; Obermeier, Andreas; Burgkart, Rainer; Forkl, Stefanie; Feihl, Susanne; Wantia, Nina; Neu, Bruno; Bajbouj, Monther; von Delius, Stefan; Schmid, Roland M.; Algül, Hana; Weber, Andreas

2014-01-01

Bacterial colonization of biliary stents is one of the driving forces behind sludge formation which may result in stent occlusion. Major focus of the study was to analyze the spectrum and number of microorganisms in relation to the indwelling time of stents and the risk factors for sludge formation. 343 stents were sonicated to optimize the bacterial release from the biofilm and identified by matrix-associated laser desorption/ionization-time of flight mass spectrometer (MALDI-TOF). 2283 bacteria were analyzed in total. The most prevalent microorganisms were Enterococcus species (spp.) (504;22%), followed by Klebsiella spp. (218;10%) and Candida spp. (188;8%). Colonization of the stents mainly began with aerobic gram-positive bacteria (43/49;88%) and Candida spp. (25/49;51%), whereas stents with an indwelling time>60 days(d) showed an almost equal colonization rate by aerobic gram-negative (176/184;96%) and aerobic gram-positive bacteria (183/184;99%) and a high proportion of anaerobes (127/184;69%). Compared to stents without sludge, more Clostridium spp. [(P = 0.02; Odds Ratio (OR): 2.4; 95% confidence interval (95%CI): (1.1–4.9)]) and Staphylococcus spp. [(P = 0.03; OR (95%CI): 4.3 (1.1–16.5)] were cultured from stents with sludge. Multivariate analysis revealed a significant relationship between the number of microorganisms [P<0.01; OR (95%CI): 1.3(1.1–1.5)], the indwelling time [P<0.01; 1–15 d vs. 20–59 d: OR (95%CI): 5.6(1.4–22), 1–15 d vs. 60–3087 d: OR (95% CI): 9.5(2.5–35.7)], the presence of sideholes [P<0.01; OR (95%CI): 3.5(1.6–7.9)] and the occurrence of sludge. Stent occlusion was found in 70/343(20%) stents. In 35% of cases, stent occlusion resulted in a cholangitis or cholestasis. In conclusion, microbial colonization of the stents changed with the indwelling time. Sludge was associated with an altered spectrum and an increasing number of microorganisms, a long indwelling time and the presence of sideholes. Interestingly

Bacterial characteristics and clinical significance of ureteral double-J stents in children.

PubMed

García-Aparicio, L; Blázquez-Gómez, E; Martin, O; Krauel, L; de Haro, I; Rodó, J

2015-01-01

To determine the incidence of urinary tract infection in those patients that we have used an ureteral double-J stent as internal diversion after urological procedures. We reviewed all the medical records of patients who had a ureteral double-J stent after a urological procedure from August 2007 to May 2013. We have analyzed the following data: age, gender, type of prophylaxis, incidence of urinary tract infection (UTI), days of internal diversion with double-J stent, surgical procedure, bacterial characteristics, bacterial sensibility to antibiotics and UTI treatment. We have used 73 double-J stents as ureteral internal diversion in 67 patients with a mean age of 44.73±57.23. Surgical procedures were 50 laparoscopic Anderson-Hynes pyeloplasties in 49 patients, and 20 high-pressure balloon dilatation of the ureterovesical junction to treat primary obstructive megaureter in 15 patients; and 3 patients with ureterovesical obstruction after endoscopic treatment of vesicoureteral reflux. Forty three stents showed a bacterial colonization in cultures. Pseudomona aeruginosa was present in 9 (20.9%) stents. Only in 12 stents, bacterial colonization was sensible to antibiotic prophylaxis. Stent colonization was higher in boys and younger patients. Four patients had a febrile UTI. Incidence of UTI in younger patients that underwent HBPD of UVJ is higher. Bacterial colonization is frequent in double-J stents but the incidence of UTI is low. Double-J colonization is higher in younger patients. Patients that underwent HPBD have a higher risk of UTI related with ureteral double J stent. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

The influence of injury severity on complication rates after primary closure or colostomy for penetrating colon trauma.

PubMed Central

Nelken, N; Lewis, F

1989-01-01

The management of penetrating colon injury has been frequently debated in the literature, yet few reports have evaluated primary closure versus diverting colostomy in similarly injured patients. Diverting colostomy is the standard of care when mucosal penetration is present, but primary closure in civilian practice has generally had excellent results, although it has been restricted to less severely injured patients. Because the degree of injury may influence choice of treatment in modern practice, various indices of injury severity have been proposed for assessment of patients with penetrating colon trauma. As yet, however, there has been no cross-comparison of repair type versus injury severity. A retrospective study 76 patients who sustained penetrating colon trauma between January 1, 1979 and December 31, 1985 and who survived for at least 24 hours was conducted. Different preferences among attending surgeons and a more aggressive approach to the use of primary closure during the years of study led to an essentially random use of primary closure and diverting colostomy for moderate levels of colon injury, with mandatory colostomy reserved for the most serious injuries. Primary closure was performed in 37 patients (three having resection and anastomosis), and colostomy was performed in 39 patients. Severity of injury was evaluated by the Injury Severity Score (ISS), Penetrating Abdominal Trauma Index (PATI), and the Flint Colon Injury Score. Complications and outcome were evaluated as a function of severity of injury, and primary closure and colostomy were compared. Demographic profiles of the two groups did not differ regarding age, sex, mechanism of injury, shock, or delay between injury and operation. The mortality rate was 2.6% for each group. Major morbidity, including septic complications, occurred in 11% of the patients of the primary closure group and in 49% of those of the colostomy group. When PATI was less than 25, the Flint score was less than or

Function and phylogeny of bacterial butyryl-CoA:acetate transferases and their diversity in the proximal colon of swine

USDA-ARS?s Scientific Manuscript database

Studying the host-associated butyrate-producing bacterial community is important because butyrate is essential for colonic homeostasis and gut health. Previous research has identified the butyryl-coA:acetate transferase (2.3.8.3) as a the main gene for butyrate production in intestinal ecosystems; h...

Simultaneous Primary Hodgkin's Lymphoma of the Sigmoid Colon and Papillary Thyroid Carcinoma in an HIV-Positive Patient.

PubMed

Liszewski, Walter; Sittig, Mark; Kandil, Emad; Van Sickels, Nicholas; Safah, Hana

2015-01-01

Primary Hodgkin's lymphoma of the colon is a rare phenomenon previously only reported in patients with chronic diverticulitis or inflammatory bowel disease. Herein we report a case of primary Hodgkin's lymphoma of the sigmoid colon in an HIV-positive patient without a history of inflammatory bowel disease or chronic diverticulitis that was later complicated by the discovery of concurrent papillary thyroid carcinoma.

Functional anatomy of the colonic bioreactor: Impact of antibiotics and Saccharomyces boulardii on bacterial composition in human fecal cylinders.

PubMed

Swidsinski, Alexander; Loening-Baucke, Vera; Schulz, Stefan; Manowsky, Julia; Verstraelen, Hans; Swidsinski, Sonja

2016-02-01

Sections of fecal cylinders were analyzed using fluorescence in situ hybridization targeting 180 bacterial groups. Samples were collected from three groups of women (N=20 each) treated for bacterial vaginosis with ciprofloxacin+metronidazole. Group A only received the combined antibiotic regimen, whereas the A/Sb group received concomitant Saccharomyces boulardii CNCM I-745 treatment, and the A_Sb group received S. boulardii prophylaxis following the 14-day antibiotic course. The number of stool cylinders analyzed was 188 out of 228 in group A, 170 out of 228 in group A/Sb, and 172 out of 216 in group A_Sb. The colonic biomass was organized into a separate mucus layer with no bacteria, a 10-30μm broad unstirred transitional layer enriched with bacteria, and a patchy fermentative area that mixed digestive leftovers with bacteria. The antibiotics suppressed bacteria mainly in the fermentative area, whereas abundant bacterial clades retreated to the transitional mucus and survived. As a result, the total concentration of bacteria decreased only by one order. These effects were lasting, since the overall recovery of the microbial mass, bacterial diversity and concentrations were still below pre-antibiotic values 4 months after the end of antibiotic treatment. Sb-prophylaxis markedly reduced antibiotic effects and improved the recovery rates. Since the colon is a sophisticated bioreactor, the study indicated that the spatial anatomy of its biomass was crucial for its function. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

The effect of smoking on CT score, bacterial colonization and distribution of inflammatory cells in the upper airways of patients with chronic rhinosinusitis.

PubMed

Uhliarova, Barbora; Adamkov, Marian; Svec, Martin; Calkovska, Andrea

2014-06-01

The study was designed to determine whether smoking affects CT score, bacterial colonization of the upper airways and distribution of inflammatory cells in nasal mucosa in patients with chronic rhinosinusitis. Sixty-four patients were enrolled in the prospective study. We characterized differences in CT score, rate of revision surgery, differences in bacterial colonization in the middle nasal meatus and distribution of inflammatory cells in nasal tissue in smoking and non-smoking patients with chronic rhinosinusitis with nasal polyps (CRSwNP), chronic rhinosinusitis without nasal polyps (CRSsNP) and control group. Direct tobacco use was associated with significantly more severe form of the disease according to the preoperative CT investigation of paranasal sinuses using Lund-Mackay scoring system in both CRSwNP (p = 0.035) and CRSsNP (p = 0.023) groups. More intense colonization of upper-respiratory tract by the pathogenic bacteria in smokers compared to non-smokers was found. Non-pathogenic bacterial flora was more often present in non-smokers compared to smokers. Plasma cells and lymphocytes were the most numerous cells in nasal tissue in all three groups. In smokers with presence of pathogenic bacteria in middle nasal meatus there was stronger neutrophil (p = 0.002) and macrophage infiltration (p = 0.044) in CRSsNP group. Tobacco smoke exposure is related to higher Lund-Mackay score, increased colonization by pathogenic bacteria and lower incidence of commensals in middle nasal meatus, but does not influence cell distribution in nasal mucosa in patients with chronic rhinosinusitis.

Cystic fibrosis and bacterial colonization define the sputum N-glycosylation phenotype.

PubMed

Venkatakrishnan, Vignesh; Thaysen-Andersen, Morten; Chen, Sharon C A; Nevalainen, Helena; Packer, Nicolle H

2015-01-01

Although mucin O-glycosylation of sputum from individuals suffering from cystic fibrosis (CF) is known to be altered relative to their unaffected counterparts, protein N-glycosylation of CF sputum remains structurally and functionally under-characterized. We report the first N-glycome of soluble proteins in sputum derived from five CF patients, two pathogen-free and two pathogen-infected/colonized non-CF individuals suffering from other pulmonary conditions. N-Glycans were profiled using porous graphitized carbon-liquid chromatography-negative ion-tandem mass spectrometry following enzymatic release from sputum proteins. The composition, topology and linkage isomers of 68 N-glycans were characterized and relatively quantified. Recurring structural features in all sputum N-glycomes were terminal α2,6-sialylation, α1,6-core fucosylation, β1,4-bisecting GlcNAcylation and compositions indicating paucimannosylation. Despite covering different genotypes, age, gender and microbial flora, the sputum N-glycomes showed little interpatient and longitudinal variation within CF patients. Comparative N-glycome analysis between inter-patient group revealed that lung infection/colonization, in general, extensively enriches the CF sputum N-glycosylation phenotype with paucimannose with simultaneous over-sialylation/fucosylation and under-bisecting GlcNAcylation of complex/hybrid N-glycans. In contrast, the sputum from CF patients had only slightly increased abundance of paucimannose N-glycans relative to pathogen-infected/colonized non-CF individuals. Similar to mucin O-glycosylation, protein N-glycosylation appears to be regulated primarily as a secondary effect of bacterial infection and inflammation rather than the CF pathogenesis in sputum. This study provides new structural N-glycan information to help understand the complex cellular and molecular environment of the CF affected respiratory tract. © The Author 2014. Published by Oxford University Press. All rights reserved

Bacterial Endophyte Colonization and Distribution within Plants

PubMed Central

Kandel, Shyam L.; Joubert, Pierre M.

2017-01-01

The plant endosphere contains a diverse group of microbial communities. There is general consensus that these microbial communities make significant contributions to plant health. Both recently adopted genomic approaches and classical microbiology techniques continue to develop the science of plant-microbe interactions. Endophytes are microbial symbionts residing within the plant for the majority of their life cycle without any detrimental impact to the host plant. The use of these natural symbionts offers an opportunity to maximize crop productivity while reducing the environmental impacts of agriculture. Endophytes promote plant growth through nitrogen fixation, phytohormone production, nutrient acquisition, and by conferring tolerance to abiotic and biotic stresses. Colonization by endophytes is crucial for providing these benefits to the host plant. Endophytic colonization refers to the entry, growth and multiplication of endophyte populations within the host plant. Lately, plant microbiome research has gained considerable attention but the mechanism allowing plants to recruit endophytes is largely unknown. This review summarizes currently available knowledge about endophytic colonization by bacteria in various plant species, and specifically discusses the colonization of maize plants by Populus endophytes. PMID:29186821

Bacterial and primary production in the pelagic zone of the Kara Sea

NASA Astrophysics Data System (ADS)

Sazhin, A. F.; Romanova, N. D.; Mosharov, S. A.

2010-10-01

Data on the bacterial and primary production, which were obtained simultaneously for the same water samples, are presented for three regions of the Kara Sea. The samples were collected for the transect westwards of the Yamal Peninsula, along the St. Anna Trough, and the transect in Ob Bay. Direct counts of the DAPI-stained bacterial cells were performed. The bacterial production and grazing rates were determined using a direct method when metabolic inhibitors vancomycin and penicillin were added. The primary production rates were estimated using the 14C method. The average primary production was 112.6, 58.5, and 28.7 mg C m-2 day-1, and the bacterial production was 12.8, 48.9, and 81.6 mg C m-2 day-1 along the Yamal Peninsula, the St. Anna Trough, and Ob Bay, respectively. The average bacterial carbon demand was 34.6, 134.5, and 220.4 mg C m-2 day-1 for these regions, respectively. The data obtained lead us to conclude that the phytoplankton-synthesized organic matter is generally insufficient to satisfy the bacterial carbon demand and may be completely assimilated via the heterotrophic processes in the marine ecosystems. Therefore, the bacterial activity and, consequently, the amount of the synthesized biomass (i.e., the production) both depend directly on the phytoplankton’s condition and activity. We consider these relationships to be characteristics of the Kara Sea’s biota.

[Spontaneous bacterial peritonitis].

PubMed

Velkey, Bálint; Vitális, Eszter; Vitális, Zsuzsanna

2017-01-01

Spontaneous bacterial peritonitis occurs most commonly in cirrhotic patients with ascites. Pathogens get into the circulation by intestinal translocation and colonize in peritoneal fluid. Diagnosis of spontaneous bacterial peritonitis is based on elevated polymorphonuclear leukocyte count in the ascites (>0,25 G/L). Ascites culture is often negative but aids to get information about antibiotic sensitivity in positive cases. Treatment in stable patient can be intravenous then orally administrated ciprofloxacin or amoxicillin/clavulanic acid, while in severe cases intravenous III. generation cephalosporin. Nosocomial spontaneous bacterial peritonitis often caused by Gram-positive bacteria and multi-resistant pathogens can also be expected thus carbapenem should be the choice of the empiric treatment. Antibiotic prophylaxis should be considered. Norfloxacin is used most commonly, but changes are expected due to increase in quinolone resistance. As a primary prophylaxis, a short-term antibiotic treatment is recommended after gastrointestinal bleeding for 5 days, while long-term prophylaxis is for patients with low ascites protein, and advanced disease (400 mg/day). Secondary prophylaxis is recommended for all patients recovered from spontaneous bacterial peritonitis. Due to increasing antibiotic use of antibiotics prophylaxis is debated to some degree. Orv. Hetil., 2017, 158(2), 50-57.

Bacterial and primary production in the Greenland Sea

NASA Astrophysics Data System (ADS)

Børsheim, Knut Yngve

2017-12-01

Bacterial production rates were measured in water profiles collected in the Greenland Sea and adjacent areas. Hydrography and nutrients throughout the water column were measured along 75°N from 12°W to 10°E at 20 km distance intervals. Net primary production rates from satellite sensed data were compared with literature values from 14C incubations and used for regional and seasonal comparisons. Maximum bacterial production rates were associated with the region close to the edge of the East Greenland current, and the rates decreased gradually towards the center of the Greenland Sea central gyre. Integrated over the upper 20 m the maximum bacterial production rate was 17.9 mmol C m- 2 day- 1, and east of the center of the gyre the average integrated rate was 4.6 mmol C m- 2 day- 1. It is hypothesized that high bacterial production rates in the western Greenland Sea were sustained by organic material carried from the Arctic Ocean by the East Greenland Current. The depth profiles of nitrate and phosphate were very similar both sides of the Arctic front, with 2% higher values between 500 m and 2000 m in the Arctic domain, and a N/P ratio of 13.6. The N/Si ratio varied by depth and region, with increasing silicate depletion from 1500 m depth to the surface. The rate of depletion from 1500 m depth to surface in the Atlantic domain was twice as high as in the Arctic domain. Net primary production rates in the area between the edge of the East Greenland current and the center of the Greenland Sea gyre was 96 mmol C m- 2 day- 1 at the time of the expedition in 2006, and 78 mmol C m- 2 day- 1 east of the center including the Atlantic domain. Annual net primary production estimated from satellite data in the Greenland Sea increased substantially in the period between 2003 and 2016, and the rate of increase was lowest close to the East Greenland Current.

Differentiation of epithelial cells to M cells in response to bacterial colonization on the follicle-associated epithelium of Peyer's patch in rat small intestine.

PubMed

Chin, Keigi; Onishi, Sachiko; Yuji, Midori; Inamoto, Tetsurou; Qi, Wang-Mei; Warita, Katsuhiko; Yokoyama, Toshifumi; Hoshi, Nobuhiko; Kitagawa, Hiroshi

2006-10-01

To clarify the relationship between M cells and intestinal microflora, histoplanimetrical investigation into the bacterial colonization and the differentiation to M cells was carried out in rat Peyer's patch under physiological conditions. The follicle-associated epithelium (FAE), except for the narrow area of apical region, was closely covered with both neighboring intestinal villi and a thick mucous layer, the latter of which also filled the intervillous spaces as well as the space between the FAE and the neighboring intestinal villi. Indigenous bacteria adhered almost constantly to the narrow areas of apical regions of both intestinal villi and the FAE. Bacterial colonies were occasionally located on the basal to middle region of FAE, where M cells also appeared, forming large pockets. When bacterial colonies were located on the basal to middle region of FAE, bacteria with the same morphological characteristics also proliferated in the intervillous spaces neighboring the Peyer's patch. In cases with no bacterial colonies on the basal to middle region of FAE, however, M cells were rare in the FAE. Histoplanimetrical analysis showed the similar distribution pattern of bacterial colonies on the FAE and M cells in the FAE. M cells ultrastructurally engulfed indigenous bacteria, which were then transported to the pockets. These results suggest that indigenous bacterial colonization on the FAE stimulates the differentiation of M cells in the FAE under physiological conditions. The uptake of bacteria by M cells might contribute the regulation of the development of indigenous bacterial colonies in the small intestine.

A Murine Model of Group B Streptococcus Vaginal Colonization.

PubMed

Patras, Kathryn A; Doran, Kelly S

2016-11-16

Streptococcus agalactiae (group B Streptococcus, GBS), is a Gram-positive, asymptomatic colonizer of the human gastrointestinal tract and vaginal tract of 10 - 30% of adults. In immune-compromised individuals, including neonates, pregnant women, and the elderly, GBS may switch to an invasive pathogen causing sepsis, arthritis, pneumonia, and meningitis. Because GBS is a leading bacterial pathogen of neonates, current prophylaxis is comprised of late gestation screening for GBS vaginal colonization and subsequent peripartum antibiotic treatment of GBS-positive mothers. Heavy GBS vaginal burden is a risk factor for both neonatal disease and colonization. Unfortunately, little is known about the host and bacterial factors that promote or permit GBS vaginal colonization. This protocol describes a technique for establishing persistent GBS vaginal colonization using a single β-estradiol pre-treatment and daily sampling to determine bacterial load. It further details methods to administer additional therapies or reagents of interest and to collect vaginal lavage fluid and reproductive tract tissues. This mouse model will further the understanding of the GBS-host interaction within the vaginal environment, which will lead to potential therapeutic targets to control maternal vaginal colonization during pregnancy and to prevent transmission to the vulnerable newborn. It will also be of interest to increase our understanding of general bacterial-host interactions in the female vaginal tract.

The social structure of microbial community involved in colonization resistance.

PubMed

He, Xuesong; McLean, Jeffrey S; Guo, Lihong; Lux, Renate; Shi, Wenyuan

2014-03-01

It is well established that host-associated microbial communities can interfere with the colonization and establishment of microbes of foreign origins, a phenomenon often referred to as bacterial interference or colonization resistance. However, due to the complexity of the indigenous microbiota, it has been extremely difficult to elucidate the community colonization resistance mechanisms and identify the bacterial species involved. In a recent study, we have established an in vitro mice oral microbial community (O-mix) and demonstrated its colonization resistance against an Escherichia coli strain of mice gut origin. In this study, we further analyzed the community structure of the O-mix by using a dilution/regrowth approach and identified the bacterial species involved in colonization resistance against E. coli. Our results revealed that, within the O-mix there were three different types of bacterial species forming unique social structure. They act as 'Sensor', 'Mediator' and 'Killer', respectively, and have coordinated roles in initiating the antagonistic action and preventing the integration of E. coli. The functional role of each identified bacterial species was further confirmed by E. coli-specific responsiveness of the synthetic communities composed of different combination of the identified players. The study reveals for the first time the sophisticated structural and functional organization of a colonization resistance pathway within a microbial community. Furthermore, our results emphasize the importance of 'Facilitation' or positive interactions in the development of community-level functions, such as colonization resistance.

Taste sensing in the colon.

PubMed

Kaji, Izumi; Karaki, Shin-ichiro; Kuwahara, Atsukazu

2014-01-01

The colonic lumen is continually exposed to many compounds, including beneficial and harmful compounds that are produced by colonic microflora. The intestinal epithelia form a barrier between the internal and luminal (external) environments. Chemical receptors that sense the luminal environment are thought to play important roles as sensors and as modulators of epithelial cell functions. The recent molecular identification of various membrane receptor proteins has revealed the sensory role of intestinal epithelial cells. Nutrient sensing by these receptors in the small intestine is implicated in nutrient absorption and metabolism. However, little is known about the physiological roles of chemosensors in the large intestine. Since 1980s, researchers have examined the effects of short-chain fatty acids (SCFA), the primary products of commensal bacteria, on gut motility, secretion, and incretin release, for example. In this decade, the SCFA receptor genes and their expression were identified in the mammalian colon. Furthermore, many other chemical receptors, including taste and olfactory receptors have been found in colonic epithelial cells. These findings indicate that the large intestinal epithelia express chemosensors that detect the luminal contents, particularly bacterial metabolites, and induce the host defense systems and the modulation of systemic metabolism via incretin release. In this review, we describe the local effects of chemical stimuli on the lumen associated with the expression pattern of sensory receptors. We propose that sensory receptors expressed in the colonic mucosa play important roles in luminal chemosensing to maintain homeostasis.

The impact of date palm fruits and their component polyphenols, on gut microbial ecology, bacterial metabolites and colon cancer cell proliferation.

PubMed

Eid, Noura; Enani, Sumia; Walton, Gemma; Corona, Giulia; Costabile, Adele; Gibson, Glenn; Rowland, Ian; Spencer, Jeremy P E

2014-01-01

The fruit of the date palm (Phoenix dactylifera L.) is a rich source of dietary fibre and polyphenols. We have investigated gut bacterial changes induced by the whole date fruit extract (digested date extract; DDE) and its polyphenol-rich extract (date polyphenol extract; DPE) using faecal, pH-controlled, mixed batch cultures mimicking the distal part of the human large intestine, and utilising an array of microbial group-specific 16S rRNA oligonucleotide probes. Fluorescence microscopic enumeration indicated that there was a significant increase in the growth of bifidobacteria in response to both treatments, whilst whole dates also increased bacteroides at 24 h and the total bacterial counts at later fermentation time points when compared with DPE alone. Bacterial metabolism of whole date fruit led to the production of SCFA, with acetate significantly increasing following bacterial incubation with DDE. In addition, the production of flavonoid aglycones (myricetin, luteolin, quercetin and apigenin) and the anthocyanidin petunidin in less than 1 h was also observed. Lastly, the potential of DDE, DPE and metabolites to inhibit Caco-2 cell growth was investigated, indicating that both were capable of potentially acting as antiproliferative agents in vitro, following a 48 h exposure. This potential to inhibit growth was reduced following fermentation. Together these data suggest that consumption of date fruits may enhance colon health by increasing beneficial bacterial growth and inhibiting the proliferation of colon cancer cells. This is an early suggestion that date intake by humans may aid in the maintenance of bowel health and even the reduction of colorectal cancer development.

Colonic responses to Lactobacillus farciminis treatment in trinitrobenzene sulphonic acid-induced colitis in rats.

PubMed

Lamine, F; Eutamène, H; Fioramonti, J; Buéno, L; Théodorou, V

2004-12-01

It has recently been shown that Lactobacillus farciminis treatment exerts an anti-inflammatory effect in trinitrobenzene sulphonic acid (TNBS)-induced colitis partly through a nitric oxide release by this strain. The aim of this study was to evaluate whether L. farciminis treatment shares also the general mechanisms of action involved in the beneficial effect of probiotics in the colonic inflammatory process. Rats received L. farciminis for 15 days before and 4 days after intracolonic administration of TNBS or vehicle. The following parameters were evaluated: macroscopic damage of colonic mucosa, myeloperoxidase activity, cytokine mucosal levels, bacterial profile in colonic content and mucosa, bacterial translocation and colonic paracellular permeability. In the absence of TNBS, L. farciminis treatment reduced colonic paracellular permeability and increased the IL-10 level in the colonic wall. TNBS administration induced colonic macroscopic damage, associated with an increase of myeloperoxidase activity, bacterial translocation, colonic paracellular permeability and IL-1beta mucosal level, and a decrease in IL-10 mucosal level. Moreover, the bacterial profile of colonic content and mucosa was modified. All these alterations were abolished or significantly reduced by L. farciminis treatment. As previously shown, L. farciminis treatment improves TNBS-induced colitis. This study indicates that, in addition to the nitric oxide released by this bacterial strain, the anti-inflammatory action of L. farciminis involves also normalization of colonic microflora, prevention of bacterial translocation, enhancement of barrier integrity and a decrease in the IL-1beta mucosal level.

Purple rice extract supplemented diet reduces DMH- induced aberrant crypt foci in the rat colon by inhibition of bacterial β-glucuronidase.

PubMed

Summart, Ratasark; Chewonarin, Teera

2014-01-01

Purple rice has become a natural product of interest which is widely used for health promotion. This study investigated the preventive effect of purple rice extract (PRE) mixed diet on DMH initiation of colon carcinogenesis. Rats were fed with PRE mixed diet one week before injection of DMH (40 mg/kg of body weight once a week for 2 weeks). They were killed 12 hrs after a second DMH injection to measure the level of O6-methylguanine and xenobiotic metabolizing enzyme activities. In rats that received PRE, guanine methylation was reduced in the colonic mucosa, but not in the liver, whereas PRE did not affect xenobiotic conjugation, with reference to glutathione-S-transferase or UDP-glucuronyl transferase. After 5 weeks, rats that received PRE with DMH injection had fewer ACF in the colon than those treated with DMH alone. Interestingly, a PRE mixed diet inhibited the activity of bacterial β-glucuronidase in rat feces, a critical enzyme for free methylazoxymethanol (MAM) release in the rat colon. These results indicated that purple rice extract inhibited β-glucuronidase activity in the colonic lumen, causing a reduction of MAM-induced colonic mucosa DNA methylation, leaded to decelerated formation of aberrant crypt foci in the rat colon. The supplemented purple rice extract might thus prevent colon carcinogenesis by the alteration of the colonic environment, and thus could be further developed for neutraceutical products for colon cancer prevention.

Characterization and comparison of the temporal dynamics of ruminal bacterial microbiota colonizing rice straw and alfalfa hay within ruminants.

PubMed

Liu, Junhua; Zhang, Mengling; Xue, Chunxu; Zhu, Weiyun; Mao, Shengyong

2016-12-01

Three ruminally cannulated Holstein cows were used to characterize the dynamics of bacterial colonization of rice straw and alfalfa hay and to assess the differences in the composition and inferred gene function of the colonized microbiota between these 2 forages. Nonincubated (0h) rice straw and alfalfa hay samples and residues in nylon bags incubated for 0.5, 2, 6, 16, and 48h were analyzed for dry matter and were used for DNA extraction and MiSeq (Illumina Inc., San Diego, CA) sequencing of the 16S rRNA gene. The microbial communities that colonized the air-dried and nonincubated (0h) rice straw and alfalfa hay were both dominated by members of the Proteobacteria (contributing toward 70.47% of the 16S RNA reads generated). In situ incubation of the 2 forages revealed major shifts in the community composition: Proteobacteria were replaced within 30min by members belonging to the Bacteroidetes and Firmicutes, contributing toward 51.9 and 36.6% of the 16S rRNA reads generated, respectively. A second significant shift was observed after 6h of rumen incubation, when members of the Spirochaetes and Fibrobacteria phyla became abundant in the forage-adherent community. During the first 30min of rumen incubation, ~20.7 and 36.1% of the rice straw and alfalfa hay, respectively, were degraded, whereas little biomass degradation occurred between 30min and 2h after the rice straw or alfalfa hay was placed in the rumen. Significant differences were noted in attached bacterial community structure between the 2 forage groups, and the abundances of dominant genera Anaeroplasma, Butyrivibrio, Fibrobacter, and Prevotella were affected by the forage types. Real-time PCR results showed that the 16S rRNA copies of total bacteria attached to these 2 forages were affected by the forage types and incubation time, and higher numbers of attached bacterial 16S rRNA were observed in the alfalfa hay samples than in the rice straw from 0.5 to 16h of incubation. The metagenomes predicted by

Genital tract shedding of herpes simplex virus type 2 in women: effects of hormonal contraception, bacterial vaginosis, and vaginal group B Streptococcus colonization.

PubMed

Cherpes, Thomas L; Melan, Melissa A; Kant, Jeffrey A; Cosentino, Lisa A; Meyn, Leslie A; Hillier, Sharon L

2005-05-15

Genital infections due to herpes simplex virus type 2 (HSV-2) are characterized by frequent reactivation and shedding of the virus and by the attendant risk of transmission to sexual partners. We investigated the effects of vaginal coinfections and hormonal contraceptive use on genital tract shedding of HSV-2 in women. A total of 330 HSV-2-seropositive women were followed every 4 months for a year. At each visit, one vaginal swab specimen was obtained for detection of HSV-2 by polymerase chain reaction, a second vaginal swab specimen was obtained for detection of group B Streptococcus (GBS) organisms and yeast by culture, and a vaginal smear was obtained for the diagnosis of bacterial vaginosis by Gram staining. HSV-2 DNA was detected in 88 (9%) of 956 vaginal swab specimens. Independent predictors of genital tract shedding of HSV-2 were HSV-2 seroconversion during the previous 4 months (adjusted odds ratio [aOR], 3.0; 95% confidence interval [CI], 1.3-6.8), bacterial vaginosis (aOR, 2.3; 95% CI, 1.3-4.0), high-density vaginal GBS colonization (aOR, 2.2; 95% CI, 1.3-3.8), and use of hormonal contraceptives (aOR, 1.8; 95% CI, 1.1-2.8). The present study identifies hormonal contraceptive use, bacterial vaginosis, and high-density vaginal GBS colonization as risk factors for genital tract shedding of HSV-2 in women. Because hormonal contraceptives are used by millions of women worldwide and because bacterial vaginosis and vaginal GBS colonization are common vaginal conditions, even modest associations with HSV-2 shedding would result in substantial attributable risks for transmission of the virus.

Hospitalized Premature Infants Are Colonized by Related Bacterial Strains with Distinct Proteomic Profiles

PubMed Central

Xiong, Weili; Olm, Matthew R.; Thomas, Brian C.; Baker, Robyn; Firek, Brian; Morowitz, Michael J.; Hettich, Robert L.

2018-01-01

ABSTRACT During the first weeks of life, microbial colonization of the gut impacts human immune system maturation and other developmental processes. In premature infants, aberrant colonization has been implicated in the onset of necrotizing enterocolitis (NEC), a life-threatening intestinal disease. To study the premature infant gut colonization process, genome-resolved metagenomics was conducted on 343 fecal samples collected during the first 3 months of life from 35 premature infants housed in a neonatal intensive care unit, 14 of whom developed NEC, and metaproteomic measurements were made on 87 samples. Microbial community composition and proteomic profiles remained relatively stable on the time scale of a week, but the proteome was more variable. Although genetically similar organisms colonized many infants, most infants were colonized by distinct strains with metabolic profiles that could be distinguished using metaproteomics. Microbiome composition correlated with infant, antibiotics administration, and NEC diagnosis. Communities were found to cluster into seven primary types, and community type switched within infants, sometimes multiple times. Interestingly, some communities sampled from the same infant at subsequent time points clustered with those of other infants. In some cases, switches preceded onset of NEC; however, no species or community type could account for NEC across the majority of infants. In addition to a correlation of protein abundances with organism replication rates, we found that organism proteomes correlated with overall community composition. Thus, this genome-resolved proteomics study demonstrated that the contributions of individual organisms to microbiome development depend on microbial community context. PMID:29636439

Comparison of Bacterial Community Composition of Primary and Persistent Endodontic Infections Using Pyrosequencing.

PubMed

Tzanetakis, Giorgos N; Azcarate-Peril, M Andrea; Zachaki, Sophia; Panopoulos, Panos; Kontakiotis, Evangelos G; Madianos, Phoebus N; Divaris, Kimon

2015-08-01

Elucidating the microbial ecology of endodontic infections (EIs) is a necessary step in developing effective intracanal antimicrobials. The aim of the present study was to investigate the bacterial composition of symptomatic and asymptomatic primary and persistent infections in a Greek population using high-throughput sequencing methods. 16S amplicon pyrosequencing of 48 root canal bacterial samples was conducted, and sequencing data were analyzed using an oral microbiome-specific and a generic (Greengenes) database. Bacterial abundance and diversity were examined by EI type (primary or persistent), and statistical analysis was performed by using non-parametric and parametric tests accounting for clustered data. Bacteroidetes was the most abundant phylum in both infection groups. Significant, albeit weak associations of bacterial diversity were found, as measured by UniFrac distances with infection type (analyses of similarity, R = 0.087, P = .005) and symptoms (analyses of similarity, R = 0.055, P = .047). Persistent infections were significantly enriched for Proteobacteria and Tenericutes compared with primary ones; at the genus level, significant differences were noted for 14 taxa, including increased enrichment of persistent infections for Lactobacillus, Streptococcus, and Sphingomonas. More but less abundant phyla were identified using the Greengenes database; among those, Cyanobacteria (0.018%) and Acidobacteria (0.007%) were significantly enriched among persistent infections. Persistent infections showed higher phylogenetic diversity (PD) (asymptomatic: PD = 9.2, standard error [SE] = 1.3; symptomatic: PD = 8.2, SE = 0.7) compared with primary infections (asymptomatic: PD = 5.9, SE = 0.8; symptomatic: PD = 7.4, SE = 1.0). The present study revealed a high bacterial diversity of EI and suggests that persistent infections may have more diverse bacterial communities than primary infections. Copyright © 2015 American Association of Endodontists. Published by

Trimeric autotransporter adhesins contribute to Actinobacillus pleuropneumoniae pathogenicity in mice and regulate bacterial gene expression during interactions between bacteria and porcine primary alveolar macrophages.

PubMed

Qin, Wanhai; Wang, Lei; Zhai, Ruidong; Ma, Qiuyue; Liu, Jianfang; Bao, Chuntong; Zhang, Hu; Sun, Changjiang; Feng, Xin; Gu, Jingmin; Du, Chongtao; Han, Wenyu; Langford, P R; Lei, Liancheng

2016-01-01

Actinobacillus pleuropneumoniae is an important pathogen that causes respiratory disease in pigs. Trimeric autotransporter adhesin (TAA) is a recently discovered bacterial virulence factor that mediates bacterial adhesion and colonization. Two TAA coding genes have been found in the genome of A. pleuropneumoniae strain 5b L20, but whether they contribute to bacterial pathogenicity is unclear. In this study, we used homologous recombination to construct a double-gene deletion mutant, ΔTAA, in which both TAA coding genes were deleted and used it in in vivo and in vitro studies to confirm that TAAs participate in bacterial auto-aggregation, biofilm formation, cell adhesion and virulence in mice. A microarray analysis was used to determine whether TAAs can regulate other A. pleuropneumoniae genes during interactions with porcine primary alveolar macrophages. The results showed that deletion of both TAA coding genes up-regulated 36 genes, including ene1514, hofB and tbpB2, and simultaneously down-regulated 36 genes, including lgt, murF and ftsY. These data illustrate that TAAs help to maintain full bacterial virulence both directly, through their bioactivity, and indirectly by regulating the bacterial type II and IV secretion systems and regulating the synthesis or secretion of virulence factors. This study not only enhances our understanding of the role of TAAs but also has significance for those studying A. pleuropneumoniae pathogenesis.

Experimental evaluation of ileal patch in delayed primary repair of penetrating colon injuries: An animal study.

PubMed

Abbasi, Hamid Reza; Bolandparvaz, Shahram; Yarmohammadi, Hooman; Geramizadeh, Bita; Tanideh, Nader; Paydar, Shahram; Hosseini, Seyed Vahid

2006-10-01

Primary repair of traumatic colonic perforation is progressively gaining acceptance as the best method of management. However, when delayed, the risk of infection-related complications may increase. Here, we present a new method of repairing colon perforation in the presence of peritonitis. Acute colon injury was simulated in 22 German shepherd dogs. The dogs were randomly divided into two groups of 11 and after 24 hours they were operated on. The perforations were repaired by subserosal suture technique. In the first group (group A), ileal patch was used. In the other group (group B), the colon was closed by debridement and anastomosis. After 6 weeks, the repairs were assessed on the basis of survival, gross and histological assessments. Nine (82%) dogs in group A and six (56%) in group B survived. Ileal patch utilization significantly decreased the mortality rate (p < 0.05). The cause of death in two group A dogs and five group B dogs was peritonitis and intra-abdominal abscess formation. None of the surviving dogs showed evidence of anastomotic leakage or breakdown. Small bowel patch used in primary repair of colon injury in the presence of peritonitis may decrease the risk of postoperative infection-related complications and the mortality rate.

Dynamics of 'Candidatus Liberibacter asiaticus' Colonization of New Growth of Citrus.

PubMed

Hilf, Mark E; Luo, Weiqi

2018-05-14

'Candidatus Liberibacter asiaticus' is a phloem-colonizing intracellular bacterial pathogen of citrus associated with the disease huanglongbing. A study of patterns of colonization and bacterial population growth in new growth of different citrus types was conducted by pruning infected citron, sweet orange, sour orange, mandarin, citrange and Citrus macrophylla trees to force the growth of axillary and adventitious shoots. The first three leaves on newly emerged shoots were collected at 30, 60 and 90 days to assess colonization and population growth of 'Ca. L. asiaticus' using real time PCR (qPCR). Single trials were conducted with mandarin and citron, two trials each for citrange, sour orange and sweet orange, and four trials for C. macrophylla. In citron the proportion of colonized leaves increased significantly over time, with 67, 85 and 96% of leaves colonized at 30, 60 and 90 days, respectively. For the other citrus types the exact proportion of colonized leaves differed, but colonization exceeded 60% in mandarin, sour orange, and citrange, and exceeded 80% at 30 days in two trials with sweet orange and three trials with C. macrophylla, but there was no significant increase in the proportion of colonized leaves at 60 and 90 days. Bacteria were readily detected by 30 days in new leaves of all citrus types. Differences in the growth of the bacterial population between citrus types and at different times of the year were noted, but common trends were apparent. In general, bacterial titers peaked at 60 days, except in leaves of C. macrophylla where bacterial titers peaked at 30 days. The early and consistently high proportion of leaf colonization observed for new growth of sweet orange during two trials and for C. macrophylla during three trials indicates a near synchronous colonization of new leaves by 30 days.

Exogenous alkaline phosphatase treatment complements endogenous enzyme protection in colonic inflammation and reduces bacterial translocation in rats.

PubMed

Martínez-Moya, P; Ortega-González, M; González, R; Anzola, A; Ocón, B; Hernández-Chirlaque, C; López-Posadas, R; Suárez, M D; Zarzuelo, A; Martínez-Augustin, O; Sánchez de Medina, F

2012-08-01

Alkaline phosphatase (AP) inactivates bacterial lipopolysaccharide and may therefore be protective. The small intestine and colon express intestinal (IAP) and tissue nonspecific enzyme (TNAP), respectively. The aim of this study was to assess the therapeutic potential of exogenous AP and its complementarity with endogenous enzyme protection in the intestine, as evidenced recently. IAP was given to rats by the oral or intrarectal route (700U/kgday). Oral budesonide (1mg/kgday) was used as a reference treatment. Treatment with intrarectal AP resulted in a 54.5% and 38.0% lower colonic weight and damage score, respectively, and an almost complete normalization of the expression of S100A8, LCN2 and IL-1β (p<0.05). Oral AP was less efficacious, while budesonide had a more pronounced effect on most parameters. Both oral and intrarectal AP counteracted bacterial translocation effectively (78 and 100%, respectively, p<0.05 for the latter), while budesonide failed to exert a positive effect. AP activity was increased in the feces of TNBS colitic animals, associated with augmented sensitivity to the inhibitor levamisole, suggesting enhanced luminal release of this enzyme. This was also observed in the mouse lymphocyte transfer model of chronic colitis. In a separate time course study, TNAP was shown to increase 2-3 days after colitis induction, while dextran sulfate sodium was a much weaker inducer of this isoform. We conclude that exogenous AP exerts beneficial effects on experimental colitis, which includes protection against bacterial translocation. AP of the tissue-nonspecific isoform is shed in higher amounts to the intestinal lumen in experimental colitis, possibly aiding in intestinal protection. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bacterial communities in the small intestine respond differently to those in the caecum and colon in mice fed low- and high-fat diets

PubMed Central

Campbell, Sara; Moreau, Michael; Patel, Falshruti; Brooks, Andrew I.; Zhou, Yin Xiu; Häggblom, Max M.; Storch, Judith

2017-01-01

Bacterial communities in the mouse caecum and faeces are known to be altered by changes in dietary fat. The microbiota of the mouse small intestine, by contrast, has not been extensively profiled and it is unclear whether small intestinal bacterial communities shift with dietary fat levels. We compared the microbiota in the small intestine, caecum and colon in mice fed a low-fat (LF) or high-fat (HF) diet using 16S rRNA gene sequencing. The relative abundance of major phyla in the small intestine, Bacteriodetes, Firmicutes and Proteobacteria, was similar to that in the caecum and colon; the relative abundance of Verrucomicrobia was significantly reduced in the small intestine compared to the large intestine. Several genera were uniquely detected in the small intestine and included the aerotolerant anaerobe, Lactobacillus spp. The most abundant genera in the small intestine were accounted for by anaerobic bacteria and were identical to those identified in the large intestine. An HF diet was associated with significant weight gain and adiposity and with changes in the bacterial communities throughout the intestine, with changes in the small intestine differing from those in the caecum and colon. Prominent Gram-negative bacteria including genera of the phylum Bacteroidetes and a genus of Proteobacteria significantly changed in the large intestine. The mechanistic links between these changes and the development of obesity, perhaps involving metabolic endotoxemia, remain to be determined. PMID:28742010

Limited Colonization Undermined by Inadequate Early Immune Responses Defines the Dynamics of Decidual Listeriosis.

PubMed

Rizzuto, Gabrielle; Tagliani, Elisa; Manandhar, Priyanka; Erlebacher, Adrian; Bakardjiev, Anna I

2017-08-01

The bacterial pathogen Listeria monocytogenes causes foodborne systemic disease in pregnant women, which can lead to preterm labor, stillbirth, or severe neonatal disease. Colonization of the maternal decidua appears to be an initial step in the maternal component of the disease as well as bacterial transmission to the placenta and fetus. Host-pathogen interactions in the decidua during this early stage of infection remain poorly understood. Here, we assessed the dynamics of L. monocytogenes infection in primary human decidual organ cultures and in the murine decidua in vivo A high inoculum was necessary to infect both human and mouse deciduas, and the data support the existence of a barrier to initial colonization of the murine decidua. If successful, however, colonization in both species was followed by significant bacterial expansion associated with an inability of the decidua to mount appropriate innate cellular immune responses. The innate immune deficits included the failure of bacterial foci to attract macrophages and NK cells, cell types known to be important for early defenses against L. monocytogenes in the spleen, as well as a decrease in the tissue density of inflammatory Ly6C hi monocytes in vivo These results suggest that the infectivity of the decidua is not the result of an enhanced recruitment of L. monocytogenes to the gestational uterus but rather is due to compromised local innate cellular immune responses. Copyright © 2017 American Society for Microbiology.

The effects of light, primary production, and temperature on bacterial production at Station ALOHA

NASA Astrophysics Data System (ADS)

Viviani, D. A.; Church, M. J.

2016-02-01

In the open oceans, bacterial metabolism is responsible for a large fraction of the movement of reduced carbon through these ecosystems. While broad meta-analyses suggest that factors such as temperature or primary production control rates of bacterial production over large geographic scales, to date little is known about how these factors influence variability in bacterial production in the open sea. Here we present two years of measurements of 3H-leucine incorporation, a proxy for bacterial production, at the open ocean field site of the Hawaii Ocean Time-series, Station ALOHA (22° 45'N, 158° 00'W). By examining 3H-leucine incorporation over monthly, daily, and hourly scales, this work provides insight into processes controlling bacterial growth in this persistently oligotrophic habitat. Rates of 3H-leucine incorporation were consistently 60% greater when measured in the light than in the dark, highlighting the importance of sunlight in fueling bacterial metabolism in this ecosystem. Over diel time scales, rates of 3H-leucine incorporation were quasi-sinusoidal, with rates in the light higher near midday, while rates in the dark were greatest after sunset. Depth-integrated (0 -125 m) rates of 3H-leucine incorporation in both light and dark were more variable ( 5- and 4-fold, respectively) than coincident measurements of primary production ( 2-fold). On average, rates of bacterial production averaged 2 and 4% of primary production (in the dark and light, respectively). At near-monthly time scales, rates of 3H-leucine incorporation in both light and dark were significantly related to temperature. Our results suggest that in the subtropical oligotrophic Pacific, bacterial production appears decoupled from primary production as a result of seasonal-scale variations in temperature and light.

Activated fluid transport regulates bacterial-epithelial interactions and significantly shifts the murine colonic microbiome

PubMed Central

Keely, Simon; Kelly, Caleb J.; Weissmueller, Thomas; Burgess, Adrianne; Wagner, Brandie D.; Robertson, Charles E.; Harris, J. Kirk; Colgan, Sean P.

2012-01-01

Within the intestinal mucosa, epithelial cells serve multiple functions to partition the lumen from the lamina propria. As part of their natural function, intestinal epithelial cells actively transport electrolytes with passive water movement as a mechanism for mucosal hydration. Here, we hypothesized that electrogenic Cl- secretion, and associated mucosal hydration, influences bacterial-epithelial interactions and significantly influences the composition of the intestinal microbiota. An initial screen of different epithelial secretagogues identified lubiprostone as the most potent agonist for which to define these principles. In in vitro studies using cultured T84 cells, lubiprostone decreased E. coli translocation in a concentration-dependent manner (p < 0.001) and decreased S. typhimurium internalization and translocation by as much as 71 ± 6% (p < 0.01). Such decreases in bacterial translocation were abolished by inhibition of electrogenic Cl- secretion and water transport using the Na-K-Cl- antagonist bumetanide (p < 0.01). Extensions of these findings to microbiome analysis in vivo revealed that lubiprostone delivered orally to mice fundamentally shifted the intestinal microbiota, with notable changes within the Firmicutes and Bacteroidetes phyla of resident colonic bacteria. Such findings document a previously unappreciated role for epithelial Cl- secretion and water transport in influencing bacterial-epithelial interactions and suggest that active mucosal hydration functions as a primitive innate epithelial defense mechanism. PMID:22614705

[Colonization of Porphyromonas endodontalis in primary and secondary endodontic infections].

PubMed

Hong, Li; Hai, Ji; Yan-Yan, He; Shenghui, Yang; Benxiang, Hou

2015-02-01

This study aims to assess and compare the prevalence of Porphyromonas endodontalis (P. endodontalis) in root canals associated with primary and secondary endodontic infections by using 16s rDNA PCR and real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR). A total of 120 adult patients with one radiographically documented periapical lesion were included. Sixty teeth presented with primary endodontic infections and 60 with secondary endodontic infections requiring retreatment. P. endodontalis was identified by using 16s rDNA PCR techniques. The positive DNA expression of P. endodontalis in two types of infected root canals were quantitatively compared by using SYBR GREEN I RTFQ-PCR. The prevalence of P. endodontalis in the root canals with primary endodontic infections was significantly higher than that in root canals with secondary endodontic infections (P = 0.001). However, RTFQ-PCR results showed no significant difference in DNA expression quantities between the primary and secondary endodontic infections root canals (P = 0.303). P. endodontalis is more highly associated with root canals having primary endodontic infections, although P. endodontalis colonize in both root canals with primary and secondary chronic apical periodontitis.

Clinical images. Primary non-Hodgkin's lymphoma of the sigmoid colon in a child.

PubMed

Zhang, Ke Ren; Jia, Hui Min

2009-01-01

Primary non-Hodgkin's lymphomas of the gastrointestinal tract are rare in children, and few of these lymphomas are located in the sigmoid colon. The preoperative diagnosis rate is low. Complete resection is indicated if it can be done safely. Combination chemotherapy after resection is indicated.

Colonization by aerobic bacteria in karst: Laboratory and in situ experiments

USGS Publications Warehouse

Personne, J.-C.; Poty, F.; Mahler, B.J.; Drogue, C.

2004-01-01

Experiments were carried out to investigate the potential for bacterial colonization of different substrates in karst aquifers and the nature of the colonizing bacteria. Laboratory batch experiments were performed using limestone and PVC as substrates, a natural bacterial isolate and a known laboratory strain (Escherichia coli [E. coli]) as inocula, and karst ground water and a synthetic formula as growth media. In parallel, fragments of limestone and granite were submerged in boreholes penetrating two karst aquifers for more than one year; the boreholes are periodically contaminated by enteric bacteria from waste water. Once a month, rock samples were removed and the colonizing bacteria quantified and identified. The batch experiments demonstrated that the natural isolate and E. coli both readily colonized limestone surfaces using karst ground water as the growth medium. In contrast, bacterial colonization of both the limestone and granite substrates, when submerged in the karst, was less intense. More than 300 bacterial strains were isolated over the period sampled, but no temporal pattern in colonization was seen as far as strain, and colonization by E. coli was notably absent, although strains of Salmonella and Citrobacter were each observed once. Samples suspended in boreholes penetrating highly fractured zones were less densely colonized than those in the borehole penetrating a less fractured zone. The results suggest that contamination of karst aquifers by enteric bacteria is unlikely to be persistent. We hypothesize that this may be a result of the high flow velocities found in karst conduits, and of predation of colonizing bacteria by autochthonous zooplankton.

The effects of chemical interactions and culture history on the colonization of structured habitats by competing bacterial populations.

PubMed

van Vliet, Simon; Hol, Felix J H; Weenink, Tim; Galajda, Peter; Keymer, Juan E

2014-05-07

Bacterial habitats, such as soil and the gut, are structured at the micrometer scale. Important aspects of microbial life in such spatial ecosystems are migration and colonization. Here we explore the colonization of a structured ecosystem by two neutrally labeled strains of Escherichia coli. Using time-lapse microscopy we studied the colonization of one-dimensional arrays of habitat patches linked by connectors, which were invaded by the two E. coli strains from opposite sides. The two strains colonize a habitat from opposite sides by a series of traveling waves followed by an expansion front. When population waves collide, they branch into a continuing traveling wave, a reflected wave and a stationary population. When the two strains invade the landscape from opposite sides, they remain segregated in space and often one population will displace the other from most of the habitat. However, when the strains are co-cultured before entering the habitats, they colonize the habitat together and do not separate spatially. Using physically separated, but diffusionally coupled, habitats we show that colonization waves and expansion fronts interact trough diffusible molecules, and not by direct competition for space. Furthermore, we found that colonization outcome is influenced by a culture's history, as the culture with the longest doubling time in bulk conditions tends to take over the largest fraction of the habitat. Finally, we observed that population distributions in parallel habitats located on the same device and inoculated with cells from the same overnight culture are significantly more similar to each other than to patterns in identical habitats located on different devices inoculated with cells from different overnight cultures, even tough all cultures were started from the same -80°C frozen stock. We found that the colonization of spatially structure habitats by two interacting populations can lead to the formation of complex, but reproducible, spatiotemporal

The effects of chemical interactions and culture history on the colonization of structured habitats by competing bacterial populations

PubMed Central

2014-01-01

Background Bacterial habitats, such as soil and the gut, are structured at the micrometer scale. Important aspects of microbial life in such spatial ecosystems are migration and colonization. Here we explore the colonization of a structured ecosystem by two neutrally labeled strains of Escherichia coli. Using time-lapse microscopy we studied the colonization of one-dimensional arrays of habitat patches linked by connectors, which were invaded by the two E. coli strains from opposite sides. Results The two strains colonize a habitat from opposite sides by a series of traveling waves followed by an expansion front. When population waves collide, they branch into a continuing traveling wave, a reflected wave and a stationary population. When the two strains invade the landscape from opposite sides, they remain segregated in space and often one population will displace the other from most of the habitat. However, when the strains are co-cultured before entering the habitats, they colonize the habitat together and do not separate spatially. Using physically separated, but diffusionally coupled, habitats we show that colonization waves and expansion fronts interact trough diffusible molecules, and not by direct competition for space. Furthermore, we found that colonization outcome is influenced by a culture’s history, as the culture with the longest doubling time in bulk conditions tends to take over the largest fraction of the habitat. Finally, we observed that population distributions in parallel habitats located on the same device and inoculated with cells from the same overnight culture are significantly more similar to each other than to patterns in identical habitats located on different devices inoculated with cells from different overnight cultures, even tough all cultures were started from the same −80°C frozen stock. Conclusions We found that the colonization of spatially structure habitats by two interacting populations can lead to the formation of

Bacterial community structure in the drinking water microbiome is governed by filtration processes.

PubMed

Pinto, Ameet J; Xi, Chuanwu; Raskin, Lutgarde

2012-08-21

The bacterial community structure of a drinking water microbiome was characterized over three seasons using 16S rRNA gene based pyrosequencing of samples obtained from source water (a mix of a groundwater and a surface water), different points in a drinking water plant operated to treat this source water, and in the associated drinking water distribution system. Even though the source water was shown to seed the drinking water microbiome, treatment process operations limit the source water's influence on the distribution system bacterial community. Rather, in this plant, filtration by dual media rapid sand filters played a primary role in shaping the distribution system bacterial community over seasonal time scales as the filters harbored a stable bacterial community that seeded the water treatment processes past filtration. Bacterial taxa that colonized the filter and sloughed off in the filter effluent were able to persist in the distribution system despite disinfection of finished water by chloramination and filter backwashing with chloraminated backwash water. Thus, filter colonization presents a possible ecological survival strategy for bacterial communities in drinking water systems, which presents an opportunity to control the drinking water microbiome by manipulating the filter microbial community. Grouping bacterial taxa based on their association with the filter helped to elucidate relationships between the abundance of bacterial groups and water quality parameters and showed that pH was the strongest regulator of the bacterial community in the sampled drinking water system.

Evolving colon injury management: a review.

PubMed

Greer, Lauren T; Gillern, Suzanne M; Vertrees, Amy E

2013-02-01

The colon is the second most commonly injured intra-abdominal organ in penetrating trauma. Management of traumatic colon injuries has evolved significantly over the past 200 years. Traumatic colon injuries can have a wide spectrum of severity, presentation, and management options. There is strong evidence that most non-destructive colon injuries can be successfully managed with primary repair or primary anastomosis. The management of destructive colon injuries remains controversial with most favoring resection with primary anastomosis and others favor colonic diversion in specific circumstances. The historical management of traumatic colon injuries, common mechanisms of injury, demographics, presentation, assessment, diagnosis, management, and complications of traumatic colon injuries both in civilian and military practice are reviewed. The damage control revolution has added another layer of complexity to management with continued controversy.

Bacterial Sialidase

NASA Technical Reports Server (NTRS)

2004-01-01

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.

Down-regulation of monocarboxylate transporter 1 (MCT1) gene expression in the colon of piglets is linked to bacterial protein fermentation and pro-inflammatory cytokine-mediated signalling.

PubMed

Villodre Tudela, Carmen; Boudry, Christelle; Stumpff, Friederike; Aschenbach, Jörg R; Vahjen, Wilfried; Zentek, Jürgen; Pieper, Robert

2015-02-28

The present study investigated the influence of bacterial metabolites on monocarboxylate transporter 1 (MCT1) expression in pigs using in vivo, ex vivo and in vitro approaches. Piglets (n 24) were fed high-protein (26 %) or low-protein (18 %) diets with or without fermentable carbohydrates. Colonic digesta samples were analysed for a broad range of bacterial metabolites. The expression of MCT1, TNF-α, interferon γ (IFN-γ) and IL-8 was determined in colonic tissue. The expression of MCT1 was lower and of TNF-α and IL-8 was higher with high-protein diets (P< 0·05). MCT1 expression was positively correlated with l-lactate, whereas negatively correlated with NH₃ and putrescine (P< 0·05). The expression of IL-8 and TNF-α was negatively correlated with l-lactate and positively correlated with NH₃ and putrescine, whereas the expression of IFN-γ was positively correlated with histamine and 4-ethylphenol (P< 0·05). Subsequently, porcine colonic tissue and Caco-2 cells were incubated with Na-butyrate, NH₄Cl or TNF-α as selected bacterial metabolites or mediators of inflammation. Colonic MCT1 expression was higher after incubation with Na-butyrate (P< 0·05) and lower after incubation with NH₄Cl or TNF-α (P< 0·05). Incubation of Caco-2 cells with increasing concentrations of these metabolites confirmed the up-regulation of MCT1 expression by Na-butyrate (linear, P< 0·05) and down-regulation by TNF-α and NH₄Cl (linear, P< 0·05). The high-protein diet decreased the expression of MCT1 in the colon of pigs, which appears to be linked to NH₃- and TNF-α-mediated signalling.

Next-Generation Sequencing of Matched Primary and Metastatic Rectal Adenocarcinomas Demonstrates Minimal Mutation Gain and Concordance to Colonic Adenocarcinomas.

PubMed

Crumley, Suzanne M; Pepper, Kristi L; Phan, Alexandria T; Olsen, Randall J; Schwartz, Mary R; Portier, Bryce P

2016-06-01

-Colorectal carcinoma is the third most common cause of cancer death in males and females in the United States. Rectal adenocarcinoma can have distinct therapeutic and surgical management from colonic adenocarcinoma owing to its location and anatomic considerations. -To determine the oncologic driver mutations and better understand the molecular pathogenesis of rectal adenocarcinoma in relation to colon adenocarcinoma. -Next-generation sequencing was performed on 20 cases of primary rectal adenocarcinoma with a paired lymph node or solid organ metastasis by using an amplicon-based assay of more than 2800 Catalogue of Somatic Mutations in Cancer (COSMIC)-identified somatic mutations. -Next-generation sequencing data were obtained on both the primary tumor and metastasis from 16 patients. Most rectal adenocarcinoma cases demonstrated identical mutations in the primary tumor and metastasis (13 of 16, 81%). The mutations identified, listed in order of frequency, included TP53, KRAS, APC, FBXW7, GNAS, FGFR3, BRAF, NRAS, PIK3CA, and SMAD4. -The somatic mutations identified in our rectal adenocarcinoma cohort showed a strong correlation to those previously characterized in colonic adenocarcinoma. In addition, most rectal adenocarcinomas harbored identical somatic mutations in both the primary tumor and metastasis. These findings demonstrate evidence that rectal adenocarcinoma follows a similar molecular pathogenesis as colonic adenocarcinoma and that sampling either the primary or metastatic lesion is valid for initial evaluation of somatic mutations and selection of possible targeted therapy.

Quorum-sensing regulation governs bacterial adhesion, biofilm development, and host colonization in Pantoea stewartii subspecies stewartii.

PubMed

Koutsoudis, Maria D; Tsaltas, Dimitrios; Minogue, Timothy D; von Bodman, Susanne B

2006-04-11

The phytopathogenic bacterium Pantoea stewartii subsp. stewartii synthesizes stewartan exo/capsular polysaccharide (EPS) in a cell density-dependent manner governed by the EsaI/EsaR quorum-sensing (QS) system. This study analyzes biofilm development and host colonization of the WT and QS regulatory mutant strains of P. stewartii. First, we show that the cell density-dependent synthesis of stewartan EPS, governed by the EsaI/EsaR QS system, is required for proper bacterial adhesion and development of spatially defined, 3D biofilms. Second, a nonvirulent mutant lacking the esaI gene adheres strongly to surfaces and develops densely packed, less structurally defined biofilms in vitro. This strain appears to be arrested in a low cell density developmental mode. Exposure of this strain to exogenous N-acyl-homoserine lactone counteracts this adhesion phenotype. Third, QS mutants lacking the EsaR repressor attach poorly to surfaces and form amorphous biofilms heavily enmeshed in excess EPS. Fourth, the WT strain disseminates efficiently within the xylem, primarily in a basipetal direction. In contrast, the two QS mutant strains remain largely localized at the site of infection. Fifth, and most significantly, epifluorescence microscopic imaging of infected leaf tissue and excised xylem vessels reveals that the bacteria colonize the xylem with unexpected specificity, particularly toward the annular rings and spiral secondary wall thickenings of protoxylem, as opposed to indiscriminate growth to fill the xylem lumen. These observations are significant to bacterial plant pathogenesis in general and may reveal targets for disease control.

Quorum-sensing regulation governs bacterial adhesion, biofilm development, and host colonization in Pantoea stewartii subspecies stewartii

PubMed Central

Koutsoudis, Maria D.; Tsaltas, Dimitrios; Minogue, Timothy D.; von Bodman, Susanne B.

2006-01-01

The phytopathogenic bacterium Pantoea stewartii subsp. stewartii synthesizes stewartan exo/capsular polysaccharide (EPS) in a cell density-dependent manner governed by the EsaI/EsaR quorum-sensing (QS) system. This study analyzes biofilm development and host colonization of the WT and QS regulatory mutant strains of P. stewartii. First, we show that the cell density-dependent synthesis of stewartan EPS, governed by the EsaI/EsaR QS system, is required for proper bacterial adhesion and development of spatially defined, 3D biofilms. Second, a nonvirulent mutant lacking the esaI gene adheres strongly to surfaces and develops densely packed, less structurally defined biofilms in vitro. This strain appears to be arrested in a low cell density developmental mode. Exposure of this strain to exogenous N-acyl-homoserine lactone counteracts this adhesion phenotype. Third, QS mutants lacking the EsaR repressor attach poorly to surfaces and form amorphous biofilms heavily enmeshed in excess EPS. Fourth, the WT strain disseminates efficiently within the xylem, primarily in a basipetal direction. In contrast, the two QS mutant strains remain largely localized at the site of infection. Fifth, and most significantly, epifluorescence microscopic imaging of infected leaf tissue and excised xylem vessels reveals that the bacteria colonize the xylem with unexpected specificity, particularly toward the annular rings and spiral secondary wall thickenings of protoxylem, as opposed to indiscriminate growth to fill the xylem lumen. These observations are significant to bacterial plant pathogenesis in general and may reveal targets for disease control. PMID:16585516

Warfare between Host Immunity and Bacterial Weapons.

PubMed

Yu, Manda; Lai, Erh-Min

2017-01-11

Bacterial pathogens deploy protein secretion systems to facilitate infection and colonization of their hosts. In this issue of Cell Host & Microbe, Chen et al. (2017) report a new role for a type VI secretion effector in promoting bacterial colonization by preventing inflammasome activation induced by a type III secretion system. Copyright © 2017 Elsevier Inc. All rights reserved.

A shift from arbuscular mycorrhizal to dark septate endophytic colonization in Deschampsia flexuosa roots occurs along primary successional gradient.

PubMed

Huusko, K; Ruotsalainen, A L; Markkola, A M

2017-02-01

Soil fungal community and dominant mycorrhizal types are known to shift along with plant community changes during primary succession. However, it is not well understood how and why root fungal symbionts and colonization types vary within the plant host when the host species is able to thrive both at young and at old successional stages with different light and nutrient resource availability. We asked (i) how root fungal colonization of Deschampsia flexuosa (Poaceae) by arbuscular mycorrhizal (AM) fungi and dark septate endophytes (DSE) changes along a postglacial primary successional land uplift gradient. As neighboring vegetation may play a role in root fungal colonization, we also asked (ii) whether removal of the dominant neighbor, Empetrum nigrum ssp. hermaphroditum (Ericaceae), affects root fungal colonization of Deschampsia. We also studied whether (iii) foliar carbon (C) and nitrogen (N) concentration of Deschampsia is related to successional changes along a land uplift gradient. AM colonization decreased (-50 %), DSE colonization increased (+200 %), and foliar C declined in Deschampsia along with increasing successional age, whereas foliar N was not affected. Empetrum removal did not affect AM colonization but increased DSE sclerotial colonization especially at older successional stages. The observed decrease in foliar C coincides with an increase in canopy closure along with increasing successional age. We suggest that the shift from an AM-dominated to a DSE-dominated root fungal community in Deschampsia along a land uplift successional gradient may be related to different nutritional benefits gained through these root fungal groups.

Distinctive colonization of Bacillus sp. bacteria and the influence of the bacterial biofilm on electrochemical behaviors of aluminum coatings.

PubMed

Abdoli, Leila; Suo, Xinkun; Li, Hua

2016-09-01

Formation of biofilm is usually essential for the development of biofouling and crucially impacts the corrosion of marine structures. Here we report the attachment behaviors of Bacillus sp. bacteria and subsequent formation of bacterial biofilm on stainless steel and thermal sprayed aluminum coatings in artificial seawater. The colonized bacteria accelerate the corrosion of the steel plates, and markedly enhance the anti-corrosion performances of the Al coatings in early growth stage of the bacterial biofilm. After 7days incubation, the biofilm formed on the steel is heterogeneous while exhibits homogeneous feature on the Al coating. Atomic force microscopy examination discloses inception of formation of local pitting on steel plates associated with significantly roughened surface. Electrochemical testing suggests that the impact of the bacterial biofilm on the corrosion behaviors of marine structures is not decided by the biofilm alone, it is instead attributed to synergistic influence by both the biofilm and physicochemical characteristics of the substratum materials. Copyright © 2016 Elsevier B.V. All rights reserved.

Mucosal Barrier Depletion and Loss of Bacterial Diversity are Primary Abnormalities in Paediatric Ulcerative Colitis

PubMed Central

Alipour, Misagh; Zaidi, Deenaz; Valcheva, Rosica; Jovel, Juan; Martínez, Inés; Sergi, Consolato; Walter, Jens; Mason, Andrew L.; Wong, Gane Ka-Shu; Dieleman, Levinus A.; Carroll, Matthew W.; Huynh, Hien Q.

2016-01-01

Background and Aims: Ulcerative colitis [UC] is associated with colonic mucosa barrier defects and bacterial dysbiosis, but these features may simply be the result of inflammation. Therefore, we sought to assess whether these features are inherently abrogated in the terminal ileum [TI] of UC patients, where inflammation is absent. Methods: TI biopsies from paediatric inflammatory bowel disease [IBD] subsets [Crohn’s disease [CD; n = 13] and UC [n = 10

Colonization of overlaying water by bacteria from dry river sediments.

PubMed

Fazi, Stefano; Amalfitano, Stefano; Piccini, Claudia; Zoppini, Annamaria; Puddu, Alberto; Pernthaler, Jakob

2008-10-01

We studied the diversity, community composition and activity of the primary microbial colonizers of the water above freshly re-wetted sediments from a temporary river. Dried sediments, collected from Mulargia River (Sardinia, Italy), were covered with sterile freshwater in triplicate microcosms, and changes of the planktonic microbial assemblage were monitored over a 48 h period. During the first 9 h bacterial abundance was low (1.5 x 10(4) cells ml(-1)); it increased to 3.4 x 10(6) cells ml(-1) after 28 h and did not change thereafter. Approximately 20% of bacteria exhibited DNA de novo synthesis already after 9 h of incubation. Changes of the ratios of (3)H-leucine to (3)H-thymidine incorporation rates indicated a shift of growth patterns during the experiment. Extracellular enzyme activity showed a maximum at 48 h with aminopeptidase activity (430.8 +/- 22.6 nmol MCA l(-1) h(-1)) significantly higher than alkaline phosphatase (98.6 +/- 4.3 nmol MUF l(-1) h(-1)). The primary microbial colonizers of the overlaying water - as determined by 16S rRNA gene sequence analysis - were related to at least six different phylogenetic lineages of Bacilli and to Alphaproteobacteria (Brevundimonas spp. and Caulobacter spp.). Large bacterial cells affiliated to one clade of Bacillus sp. were rare in the dried sediments, but constituted the majority of the planktonic microbial assemblage and of cells with detectable DNA-synthesis until 28 h after re-wetting. Their community contribution decreased in parallel with a rise of flagellated and ciliated protists. Estimates based on cell production rates suggested that the rapidly enriched Bacillus sp. suffered disproportionally high loss rates from selective predation, thus favouring the establishment of a more heterogenic assemblage of microbes (consisting of Proteobacteria, Actinobacteria and Cytophaga-Flavobacteria). Our results suggest that the primary microbial colonizers of the water above dried sediments are passively released

Anaerobic bacteria commonly colonize the lower airways of intubated ICU patients.

PubMed

Agvald-Ohman, C; Wernerman, J; Nord, C E; Edlund, C

2003-05-01

To investigate respiratory tract colonization by aerobic and anaerobic bacteria in mechanically ventilated patients. Bacterial colonization of the stomach and the respiratory tract was qualitatively and quantitatively analyzed over time in 41 consecutive mechanically ventilated patients in a Swedish intensive care unit (ICU), with special emphasis on elucidation of the role of anaerobic bacteria in the lower respiratory tract. Samples were taken from the oropharynx, gastric juice, subglottic space and trachea within 24 h (median 14 h) of intubation, and then every third day until day 18 and every fifth day until day 33. The patients were often heavily colonized with microorganisms not considered to belong to a healthy normal oropharyngeal and gastric flora on admission to the ICU. A majority harbored enterococci, coagulase-negative staphylococci and Candida spp. in at least one site on day 1. Anaerobic bacteria, mainly peptostreptococci and Prevotella spp., were isolated from subglottic and/or tracheal secretions in 59% of the patients. Different routes of tracheal colonization for different groups of microorganisms were found. Primary or concomitant colonization of the oropharynx with staphylococci, enterococci, enterobacteria and Candida was often seen, while Pseudomonas spp., other non-fermenting Gram-negative rods and several anaerobic species often primarily colonized the trachea, indicating exogenous or direct gastrointestinal routes of colonization. Mechanically ventilated patients were heavily colonized in their lower airways by potential pathogenic microorganisms, including a high load of anaerobic bacteria. Different routes of colonization were shown for different species.

The human jejunum has an endogenous microbiota that differs from those in the oral cavity and colon.

PubMed

Sundin, Olof H; Mendoza-Ladd, Antonio; Zeng, Mingtao; Diaz-Arévalo, Diana; Morales, Elisa; Fagan, B Matthew; Ordoñez, Javier; Velez, Philip; Antony, Nishaal; McCallum, Richard W

2017-07-17

The upper half of the human small intestine, known as the jejunum, is the primary site for absorption of nutrient-derived carbohydrates, amino acids, small peptides, and vitamins. In contrast to the colon, which contains 10 11 -10 12 colony forming units of bacteria per ml (CFU/ml), the normal jejunum generally ranges from 10 3 to 10 5  CFU per ml. Because invasive procedures are required to access the jejunum, much less is known about its bacterial microbiota. Bacteria inhabiting the jejunal lumen have been investigated by classical culture techniques, but not by culture-independent metagenomics. The lumen of the upper jejunum was sampled during enteroscopy of 20 research subjects. Culture on aerobic and anaerobic media gave live bacterial counts ranging from 5.8 × 10 3 CFU/ml to 8.0 × 10 6 CFU/ml. DNA from the same samples was analyzed by 16S rRNA gene-specific quantitative PCR, yielding values from 1.5 × 10 5 to 3.1 × 10 7 bacterial genomes per ml. When calculated for each sample, estimated bacterial viability ranged from effectively 100% to a low of 0.3%. 16S rRNA metagenomic analysis of uncultured bacteria by Illumina MiSeq sequencing gave detailed microbial composition by phylum, genus and species. The genera Streptococcus, Prevotella, Veillonella and Fusobacterium, were especially abundant, as well as non-oral genera including Escherichia, Klebsiella, and Citrobacter. The jejunum was devoid of the genera Alistipes, Ruminococcus, Faecalibacterium, and other extreme anaerobes abundant in the colon. In patients with higher bacterial loads, there was no significant change in microbial species composition. The jejunal lumen contains a distinctive bacterial population consisting primarily of facultative anaerobes and oxygen-tolerant obligate anaerobes similar to those found in the oral cavity. However, the frequent abundance of Enterobacteriaceae represents a major difference from oral microbiota. Although a few genera are shared with the colon, we

Epidemiology and Resistance Patterns of Bacterial and Fungal Colonization of Biliary Plastic Stents: A Prospective Cohort Study

PubMed Central

Lübbert, Christoph; Wendt, Karolin; Feisthammel, Jürgen; Moter, Annette; Lippmann, Norman; Busch, Thilo; Mössner, Joachim; Hoffmeister, Albrecht; Rodloff, Arne C.

2016-01-01

Background Plastic stents used for the treatment of biliary obstruction will become occluded over time due to microbial colonization and formation of biofilms. Treatment of stent-associated cholangitis is often not effective because of inappropriate use of antimicrobial agents or antimicrobial resistance. We aimed to assess the current bacterial and fungal etiology of stent-associated biofilms, with particular emphasis on antimicrobial resistance. Methods Patients with biliary strictures requiring endoscopic stent placement were prospectively enrolled. After the retrieval of stents, biofilms were disrupted by sonication, microorganisms were cultured, and isolates were identified by matrix-associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and/or biochemical typing. Finally, minimum inhibitory concentrations (MICs) were determined for various antimicrobial agents. Selected stents were further analyzed by fluorescence in situ hybridization (FISH). Results Among 120 patients (62.5% males, median age 64 years) with biliary strictures (35% malignant, 65% benign), 113 double pigtail polyurethane and 100 straight polyethylene stents were analyzed after a median indwelling time of 63 days (range, 1–1274 days). The stent occlusion rate was 11.5% and 13%, respectively, being associated with a significantly increased risk of cholangitis (38.5% vs. 9.1%, P<0.001). Ninety-five different bacterial and 13 fungal species were detected; polymicrobial colonization predominated (95.8% vs. 4.2%, P<0.001). Enterococci (79.3%), Enterobacteriaceae (73.7%), and Candida spp. (55.9%) were the leading pathogens. Candida species were more frequent in patients previously receiving prolonged antibiotic therapy (63% vs. 46.7%, P = 0.023). Vancomycin-resistant enterococci accounted for 13.7%, extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae with co-resistance to ciprofloxacin accounted for 13.9%, and azole-resistant Candida spp. accounted for

Epidemiology and Resistance Patterns of Bacterial and Fungal Colonization of Biliary Plastic Stents: A Prospective Cohort Study.

PubMed

Lübbert, Christoph; Wendt, Karolin; Feisthammel, Jürgen; Moter, Annette; Lippmann, Norman; Busch, Thilo; Mössner, Joachim; Hoffmeister, Albrecht; Rodloff, Arne C

2016-01-01

Plastic stents used for the treatment of biliary obstruction will become occluded over time due to microbial colonization and formation of biofilms. Treatment of stent-associated cholangitis is often not effective because of inappropriate use of antimicrobial agents or antimicrobial resistance. We aimed to assess the current bacterial and fungal etiology of stent-associated biofilms, with particular emphasis on antimicrobial resistance. Patients with biliary strictures requiring endoscopic stent placement were prospectively enrolled. After the retrieval of stents, biofilms were disrupted by sonication, microorganisms were cultured, and isolates were identified by matrix-associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and/or biochemical typing. Finally, minimum inhibitory concentrations (MICs) were determined for various antimicrobial agents. Selected stents were further analyzed by fluorescence in situ hybridization (FISH). Among 120 patients (62.5% males, median age 64 years) with biliary strictures (35% malignant, 65% benign), 113 double pigtail polyurethane and 100 straight polyethylene stents were analyzed after a median indwelling time of 63 days (range, 1-1274 days). The stent occlusion rate was 11.5% and 13%, respectively, being associated with a significantly increased risk of cholangitis (38.5% vs. 9.1%, P<0.001). Ninety-five different bacterial and 13 fungal species were detected; polymicrobial colonization predominated (95.8% vs. 4.2%, P<0.001). Enterococci (79.3%), Enterobacteriaceae (73.7%), and Candida spp. (55.9%) were the leading pathogens. Candida species were more frequent in patients previously receiving prolonged antibiotic therapy (63% vs. 46.7%, P = 0.023). Vancomycin-resistant enterococci accounted for 13.7%, extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae with co-resistance to ciprofloxacin accounted for 13.9%, and azole-resistant Candida spp. accounted for 32.9% of the respective

Electrolyzed Saline Irrigation for Elimination of Bacterial Colonization in the Empyema Space.

PubMed

Nakamoto, Kembu; Takeshige, Motohiro; Fujii, Toshiyuki; Hashiyada, Hiroshi; Yoshida, Kazuya; Kawamoto, Sadahiro

2016-12-01

The empyema space is refractory to elimination of bacterial colonization. Electrolyzed saline (ES) was used as intra-pleural irrigation for rapid disinfection of the empyema space. Twenty consecutive patients with para-pneumonic empyema were reviewed in this study from 2007 to 2015. The empyema space was irrigated by miniaturized thoracoscopic surgery (mini VATS), and the efficacy and safety of the use of ES were evaluated. Sixteen patients were male and four were female, with a mean age of 66.5 ± 9.5 y (27-90 y). Bacterial cultures of the purulent effusions from all 20 patients had positive results. Seventeen patients subsequently underwent continuous catheter irrigation and drainage. No patient had chest pain during ES irrigation. Fever duration after mini VATS was 2.8 ± 1.8 d (0-5 d). Catheter indwelling time was 10.3 ± 7.2 d (3-33 d). Inflammatory markers significantly improved (p < 0.05) within a week after mini VATS. Eighteen patients achieved pleural disinfection, and two patients had residual pathogens, one of whom later died of lung abscess. Space closure was successful in 14 patients. No patient underwent subsequent open drainage. Nineteen (95%) patients were discharged from the hospital. This treatment was successful in 18 (90%) patients, and one (5.6%) patient experienced recurrence. The ES irrigation facilitates the rapid disinfection and closure of the empyema space.

Dientamoeba fragilis colonization is not associated with gastrointestinal symptoms in children at primary care level.

PubMed

Holtman, Gea A; Kranenberg, Justin J; Blanker, Marco H; Ott, Alewijn; Lisman-van Leeuwen, Yvonne; Berger, Marjolein Y

2017-02-01

Dientamoeba fragilis is commonly identified in children in primary care and is suspected to cause gastrointestinal disease. To determine the association between D. fragilis colonization and gastrointestinal symptoms in children. We performed a cross-sectional study with children who presented in primary care with gastrointestinal symptoms. The associations between D. fragilis colonization and specific symptoms were explored by means of logistic regression analyses. Asymptomatic siblings of these cases were invited as control subjects for a case-control analysis, where we explored the association between D. fragilis and gastrointestinal symptoms with conditional logistic regression analysis. In the cross-sectional study, 107 children were included. Their median age was 9 years (interquartile range = 6-12) and 38 (35.5%) were boys. Colonization of D. fragilis was present in 59 children (55.1%). The absence of D. fragilis was associated with soft to watery stool [odds ratio (OR) = 0.29; 95% confidence interval (CI) = 0.10-0.85], chronic diarrhoea (OR = 0.42; 95% CI = 0.18-0.97) and fatigue (OR = 0.45; 95% CI = 0.20-0.99). The case-control analyses included 44 children in each group. Dientamoeba fragilis colonization was not observed more often in cases than in controls after adjustment for age and sex (OR = 1.02; 95% CI = 0.28-3.65). Dientamoeba fragilis is a common parasite in children with and without gastrointestinal symptoms. The anomalous finding of the association between the absence of D. fragilis with soft to watery stools, chronic diarrhoea and fatigue are inexplicable. Our study suggests that D. fragilis colonization does not increase the risk for gastrointestinal symptoms. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Dietary proline supplementation alters colonic luminal microbiota and bacterial metabolite composition between days 45 and 70 of pregnancy in Huanjiang mini-pigs.

PubMed

Ji, Yujiao; Guo, Qiuping; Yin, Yulong; Blachier, Francois; Kong, Xiangfeng

2018-01-01

findings indicate that L -proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.

Bacterial colonization patterns in mechanically ventilated patients with traumatic and medical head injury. Incidence, risk factors, and association with ventilator-associated pneumonia.

PubMed

Ewig, S; Torres, A; El-Ebiary, M; Fábregas, N; Hernández, C; González, J; Nicolás, J M; Soto, L

1999-01-01

We prospectively evaluated the relation of upper airway, lower airway, and gastric colonization patterns with the development of pneumonia and its etiology in 48 patients with surgical (n = 25) and medical (n = 23) head injury. Initial colonization was assessed by cultures of nasal and pharyngeal swabs, tracheobronchial aspirates, gastric juice, and bronchoscopically retrieved protected specimen brush. Follow-up colonization was determined until the end points extubation, suspected ventilator-associated pneumonia (VAP), or death. The initial colonization rate at any site at ICU admission was 39/47 (83%). It mainly accounted for Group I pathogens (Streptococcus pneumoniae, Staphylococcus aureus, Hemophilus influenzae) of the upper and lower airways. At follow-up, colonization rates with Group II pathogens (Gram-negative enteric bacilli and Pseudomonas spp.) increased significantly. The high initial bacterial load with Group I pathogens of the upper airways and trachea decreased during Days 2 to 4, whereas that of Group II pathogens increased. Upper airway colonization was an independent predictor of follow-up tracheobronchial colonization (odds ratio [OR], 9.9; 95% confidence interval [CI], 1.8 to 56.3 for initial colonization with Group I pathogens; OR, 23.9; 95% CI, 3.8 to 153.3 for follow-up colonization with Group II pathogens). Previous (short-term) antibiotics had a protective effect against colonization with Group I pathogens of the lower respiratory tract (OR, 0.2; 95% CI, 0.05 to 0.86), but they were a risk factor for colonization with Group II pathogens (OR, 6.1; 95% CI, 1.3 to 29). Initial tracheobronchial colonization with Group I pathogens was associated with a higher probability of early onset pneumonia (OR, 4. 1; 95% CI, 0.7 to 23.3), whereas prolonged antibiotic treatment (> 24 h) independently predicted late-onset pneumonia (OR, 9.2; 95% CI, 1.7 to 51.3). We conclude that patients with head injury are colonized in the airways mainly by Group I

Colonization and infection by Helicobacter pylori in humans.

PubMed

Andersen, Leif Percival

2007-11-01

When Helicobacter pylori arrives in the human stomach, it may penetrate the mucin layer and adhere to the gastric epithelial cells or it may pass through the stomach without colonizing the mucosa. In this paper, the colonization process and the ensuing immunological response will be briefly described. Urease production is necessary for H. pylori to establish a pH-neutral microenvironment around the bacteria. The flagella enable the bacteria to move and the shape of H. pylori makes it possible to penetrate the mucin layer where it comes into contact with the gastric epithelial cells. H. pylori contains several adhesins that enable it to adhere to the epithelial cells. This adherence activates IL-8 which, together with bacterial antigens, attracts polymorphs and monocytes and causes acute gastritis. Antigen-presenting cells activate lymphocytes and other mononuclear cells that are attracted to the inflamed mucosa, causing chronic superficial gastritis and initiating a cytotoxic or an antigen-producing Th response. The infection is established within a few weeks after the primary exposure to H. pylori. After this initial colonization, many chemical, biochemical, and immunologic reactions take place that are of importance in the progress of the infection and the development of disease.

Microbiome Analysis of Stool Samples from African Americans with Colon Polyps

PubMed Central

Brim, Hassan; Yooseph, Shibu; Zoetendal, Erwin G.; Lee, Edward; Torralbo, Manolito; Laiyemo, Adeyinka O.; Shokrani, Babak; Nelson, Karen; Ashktorab, Hassan

2013-01-01

Background Colonic polyps are common tumors occurring in ~50% of Western populations with ~10% risk of malignant progression. Dietary agents have been considered the primary environmental exposure to promote colorectal cancer (CRC) development. However, the colonic mucosa is permanently in contact with the microbiota and its metabolic products including toxins that also have the potential to trigger oncogenic transformation. Aim To analyze fecal DNA for microbiota composition and functional potential in African Americans with pre-neoplastic lesions. Materials & Methods We analyzed the bacterial composition of stool samples from 6 healthy individuals and 6 patients with colon polyps using 16S ribosomal RNA-based phylogenetic microarray; the Human intestinal Tract Chip (HITChip) and 16S rRNA gene barcoded 454 pyrosequencing. The functional potential was determined by sequence-based metagenomics using 454 pyrosequencing. Results Fecal microbiota profiling of samples from the healthy and polyp patients using both a phylogenetic microarraying (HITChip) and barcoded 454 pyrosequencing generated similar results. A distinction between both sets of samples was only obtained when the analysis was performed at the sub-genus level. Most of the species leading to the dissociation were from the Bacteroides group. The metagenomic analysis did not reveal major differences in bacterial gene prevalence/abundances between the two groups even when the analysis and comparisons were restricted to available Bacteroides genomes. Conclusion This study reveals that at the pre-neoplastic stages, there is a trend showing microbiota changes between healthy and colon polyp patients at the sub-genus level. These differences were not reflected at the genome/functions levels. Bacteria and associated functions within the Bacteroides group need to be further analyzed and dissected to pinpoint potential actors in the early colon oncogenic transformation in a large sample size. PMID:24376500

Colonization of plant substrates at hydrothermal vents and cold seeps in the northeast Atlantic and Mediterranean and occurrence of symbiont-related bacteria

PubMed Central

Szafranski, Kamil M.; Deschamps, Philippe; Cunha, Marina R.; Gaudron, Sylvie M.; Duperron, Sébastien

2015-01-01

Reducing conditions with elevated sulfide and methane concentrations in ecosystems such as hydrothermal vents, cold seeps or organic falls, are suitable for chemosynthetic primary production. Understanding processes driving bacterial diversity, colonization and dispersal is of prime importance for deep-sea microbial ecology. This study provides a detailed characterization of bacterial assemblages colonizing plant-derived substrates using a standardized approach over a geographic area spanning the North-East Atlantic and Mediterranean. Wood and alfalfa substrates in colonization devices were deployed for different periods at 8 deep-sea chemosynthesis-based sites in four distinct geographic areas. Pyrosequencing of a fragment of the 16S rRNA-encoding gene was used to describe bacterial communities. Colonization occurred within the first 14 days. The diversity was higher in samples deployed for more than 289 days. After 289 days, no relation was observed between community richness and deployment duration, suggesting that diversity may have reached saturation sometime in between. Communities in long-term deployments were different, and their composition was mainly influenced by the geographical location where devices were deployed. Numerous sequences related to horizontally-transmitted chemosynthetic symbionts of metazoans were identified. Their potential status as free-living forms of these symbionts was evaluated based on sequence similarity with demonstrated symbionts. Results suggest that some free-living forms of metazoan symbionts or their close relatives, such as Epsilonproteobacteria associated with the shrimp Rimicaris exoculata, are efficient colonizers of plant substrates at vents and seeps. PMID:25774156

Bacterial profile in primary teeth with necrotic pulp and periapical lesions.

PubMed

da Silva, Léa Assed Bezerra; Nelson-Filho, Paulo; Faria, Gisele; de Souza-Gugelmin, Maria Cristina Monteiro; Ito, Izabel Yoko

2006-01-01

The objective of this study was to evaluate the bacterial profile in root canals of human primary teeth with necrotic pulp and periapical lesions using bacterial culture. A total of 20 primary teeth with necrotic pulp and radiographically visible radiolucent areas in the region of the bone furcation and/or the periapical region were selected. After crown access, 4 sterile absorbent paper points were introduced sequentially into the root canal for collection of material. After 30 s, the paper points were removed and placed in a test tube containing reduced transport fluid (RTF) and were sent for microbiological evaluation. Anaerobic microorganisms were found in 100% of the samples, black-pigmented bacilli in 30%, aerobic microorganisms in 60%, streptococci in 85%, gram-negative aerobic rods in 15% and staphylococci were not quantified. Mutans streptococci were found in 6 root canals (30%), 5 canals with Streptococcus mutans and 1 canal with Streptococcus mutans and Streptococcus sobrinus. It was concluded that in root canals of human primary teeth with necrotic pulp and periapical lesions, the infection is polymicrobial with predominance of anaerobic microorganisms.

Characterization of initial events in bacterial surface colonization by two Pseudomonas species using image analysis.

PubMed

Mueller, R F; Characklis, W G; Jones, W L; Sears, J T

1992-05-01

The processes leading to bacterial colonization on solid-water interfaces are adsorption, desorption, growth, and erosion. These processes have been measured individually in situ in a flowing system in real time using image analysis. Four different substrata (copper, silicon, 316 stainless-steel and glass) and 2 different bacterial species (Pseudomonas aeruginosa and Pseudomonas fluorescens) were used in the experiments. The flow was laminar (Re = 1.4) and the shear stress was kept constant during all experiments at 0.75 N m(-2). The surface roughness varied among the substrata from 0.002 microm (for silicon) to 0.015 microm (for copper). Surface free energies varied from 25.1 dynes cm(-1) for silicon to 31.2 dynes cm(-1) for copper. Cell curface hydrophobicity, reported as hydrocarbon partitioning values, ranged from 0.67 for Ps. fluorescens to 0.97 for Ps. aeruginosa.The adsorption rate coefficient varied by as much as a factor of 10 among the combinations of bacterial strain and substratum material, and was positively correlated with surface free energy, the surface roughness of the substratum, and the hydrophobicity of the cells. The probability of desorption decreased with increasing surface free energy and surface roughness of the substratum. Cell growth was inhibited on copper, but replication of cells overlying an initial cell layer was observed with increased exposure time to the cell-containing bulk water. A mathematical model describing cell accumulation on a substratum is presented.

Optimization of ceragenins for prevention of bacterial colonization of hydrogel contact lenses.

PubMed

Gu, Xiaobo; Jennings, Jacob D; Snarr, Jason; Chaudhary, Vinod; Pollard, Jacob E; Savage, Paul B

2013-09-17

We provided contact lens hydrogels with an antibacterial innate immune function using nonpeptide mimics of endogenous antimicrobial peptides. Antimicrobial peptide mimics, ceragenins, were prepared for either covalent attachment to hydrogels or for controlled elution from lenses. The lipophilicity of the ceragenins was varied incrementally to provide differing levels of association with hydrophobic domains in lenses. Ceragenin-containing lenses were challenged repeatedly with Staphylococcus aureus or Pseudomonas aeruginosa in nutrient media. Bacterial growth and biofilm formation on lenses were quantified. A ceragenin covalently fixed in lenses effectively inhibited S. aureus biofilm formation on lenses in 10% tryptic soy broth (approximately 3-log reduction), but did not reduce biofilm formation in 100% tryptic soy broth. Ceragenins designed to elute from lenses were incorporated at 1% relative to the dry weight of the lenses. The ceragenin with the optimal lipid content, CSA-138, prevented bacterial colonization of lenses for 15 days with P. aeruginosa and for 30 days with S. aureus (daily exchange of growth media and reinoculation with 10⁶ CFU). Measurement of CSA-138 elution showed that concentrations of the ceragenin never exceeded 5 μg/mL in a 24-hour period and that after 4 days of elution, concentrations dropped to <0.5 μg/mL, while maintaining antibacterial activity. Ceragenin CSA-138 appears well suited for providing an innate immune-like function to abiotic hydrogel contact lenses for extended periods of time. Elution of even low concentrations of CSA-138 (<0.5 μg) is sufficient to eliminate inocula of 10⁶ CFU of S. aureus and P. aeruginosa.

Enterobacter Strains Might Promote Colon Cancer.

PubMed

Yurdakul, Dilşad; Yazgan-Karataş, Ayten; Şahin, Fikrettin

2015-09-01

Many studies have been performed to determine the interaction between bacterial species and cancer. However, there has been no attempts to demonstrate a possible relationship between Enterobacter spp. and colon cancer so far. Therefore, in the present study, it is aimed to investigate the effects of Enterobacter strains on colon cancer. Bacterial proteins were isolated from 11 Enterobacter spp., one Morganella morganii, and one Escherichia coli strains, and applied onto NCM460 (Incell) and CRL1790 (ATCC) cell lines. Cell viability and proliferation were determined in MTS assay. Flow Cytometry was used to detect CD24 level and apoptosis. Real-Time PCR studies were performed to determine NFKB and Bcl2 expression. Graphpad Software was used for statistical analysis. The results showed that proteins, isolated from the Enterobacter spp., have significantly increased cell viability and proliferation, while decreasing the apoptosis of the cell lines tested. The data in the present study indicated that Enterobacter strains might promote colon cancer. Moreover, Enterobacter spp. could be a clinically important factor for colon cancer initiation and progression. Studies can be extended on animal models in order to develop new strategies for treatment.

Evaluation on the effects of 0.1% Peumus boldus leaf and Spiraea ulmaria plant extract combination on bacterial colonization in canine atopic dermatitis: A preliminary randomized, placebo controlled, double-blinded study.

PubMed

Santoro, Domenico; Bohannon, Mary; Ahrens, Kim; Navarro, Christelle; Gatto, Hugues; Marsella, Rosanna

2018-06-01

Defective skin barrier characterize canine atopic dermatitis (AD). Pyoderma is the most common complication. Herbal compounds have been suggested as alternatives to control bacterial colonization for their effect on natural antimicrobial peptides (AMPs). This study evaluated the effects of 0.1% Peumus boldus leaf and Spiraea ulmaria plant extract combination on clinical signs, bacterial colonization and AMPs secretion in atopic dogs compared to placebo. Twenty privately-owned atopic dogs were randomly divided in 2 groups (treatment: n = 10; placebo: n = 10) and their abdomen was sprayed every 24 h for 4 weeks. Total and inguinal clinical scores (CADESI-03), manual bacterial count, and skin washes for AMPs (cBD3-like and cCath) were performed on days 0, 14 and 28. AMPs were detected using in-house, previously-validated, canine-specific ELISAs. Data were statistically analyzed and a p < 0.05 was considered significant. Clinical scores and AMPs secretion did not differ significantly between the two groups at any time point. A significant reduction of the clinical scores was seen in the placebo group at 14 and 28 days (p < 0.04). On days 14 and 28, a reduction in the bacterial count was seen in the treated group compared with placebo (p < 0.009 and p = 0.04, respectively). Compared to baseline, a reduction in Staphylococcus spp. was seen in the treated group after 14 days of treatment (p < 0.03). These results show the efficacy of this plant extract combination against bacterial colonization, suggesting its potential usefulness in preventing bacterial infection in atopic dogs. The influence of this compound on AMPs secretion or other mechanisms should be further evaluated. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Ursodeoxycholic acid and lithocholic acid exert anti-inflammatory actions in the colon.

PubMed

Ward, Joseph B J; Lajczak, Natalia K; Kelly, Orlaith B; O'Dwyer, Aoife M; Giddam, Ashwini K; Ní Gabhann, Joan; Franco, Placido; Tambuwala, Murtaza M; Jefferies, Caroline A; Keely, Simon; Roda, Aldo; Keely, Stephen J

2017-06-01

Ward JB, Lajczak NK, Kelly OB, O'Dwyer AM, Giddam AK, Ní Gabhann J, Franco P, Tambuwala MM, Jefferies CA, Keely S, Roda A, Keely SJ. Ursodeoxycholic acid and lithocholic acid exert anti-inflammatory actions in the colon. Am J Physiol Gastrointest Liver Physiol 312: G550-G558, 2017. First published March 30, 2017; doi:10.1152/ajpgi.00256.2016.-Inflammatory bowel diseases (IBD) comprise a group of common and debilitating chronic intestinal disorders for which currently available therapies are often unsatisfactory. The naturally occurring secondary bile acid, ursodeoxycholic acid (UDCA), has well-established anti-inflammatory and cytoprotective actions and may therefore be effective in treating IBD. We aimed to investigate regulation of colonic inflammatory responses by UDCA and to determine the potential impact of bacterial metabolism on its therapeutic actions. The anti-inflammatory efficacy of UDCA, a nonmetabolizable analog, 6α-methyl-UDCA (6-MUDCA), and its primary colonic metabolite lithocholic acid (LCA) was assessed in the murine dextran sodium sulfate (DSS) model of mucosal injury. The effects of bile acids on cytokine (TNF-α, IL-6, Il-1β, and IFN-γ) release from cultured colonic epithelial cells and mouse colonic tissue in vivo were investigated. Luminal bile acids were measured by gas chromatography-mass spectrometry. UDCA attenuated release of proinflammatory cytokines from colonic epithelial cells in vitro and was protective against the development of colonic inflammation in vivo. In contrast, although 6-MUDCA mimicked the effects of UDCA on epithelial cytokine release in vitro, it was ineffective in preventing inflammation in the DSS model. In UDCA-treated mice, LCA became the most common colonic bile acid. Finally, LCA treatment more potently inhibited epithelial cytokine release and protected against DSS-induced mucosal inflammation than did UDCA. These studies identify a new role for the primary metabolite of UDCA, LCA, in preventing colonic

Lesioning of TRPV1 Expressing Primary Afferent Neurons Prevents PAR-2 Induced Motility, but Not Mechanical Hypersensitivity in the Rat Colon

PubMed Central

Suckow, Shelby K.; Anderson, Ethan M.; Caudle, Robert M.

2011-01-01

Background Proteinase activated receptor 2 (PAR-2) is expressed by many neurons in the colon, including primary afferent neurons that co-express transient receptor potential vanilloid 1 (TRPV1). Activation of PAR-2 receptors was previously found to enhance colonic motility, increase secretion and produce hypersensitivity to mechanical stimuli. This study examined the functional role of TRPV1/PAR-2 expressing neurons that innervate the colon by lesioning TRPV1 bearing neurons with the highly selective and potent TRPV1 agonist resiniferatoxin. Methods Colonic motility in response to PAR-2 activation was evaluated in vitro using isolated segments of descending colon and in vivo using manometry. Colonic mechanical nociceptive thresholds were measured using colorectal distension. TRPV1 expressing neurons were selectively lesioned with resiniferatoxin. Key Results In vitro the PAR-2 agonists trypsin and SLIGRL did not alter contractions of colon segments when applied alone, however, the agents enhanced acetylcholine stimulated contraction. In vivo, PAR-2 agonists administered intraluminally induced contractions of the colon and produced hypersensitivity to colorectal distention. The PAR-2 agonist enhancement of colonic contraction was eliminated when TRPV1 expressing neurons were lesioned with resiniferatoxin, but the PAR-2 agonist induced hypersensitivity remained in the lesioned animals. Conclusions and Inferences Our findings indicate that TRPV1/PAR-2 expressing primary afferent neurons mediate an extrinsic motor reflex pathway in the colon. These data, coupled with our previous studies, also indicate that the recently described colospinal afferent neurons are nociceptive, suggesting that these neurons may be useful targets for the pharmacological control of pain in diseases such as irritable bowel syndrome. PMID:22168801

Lesioning of TRPV1 expressing primary afferent neurons prevents PAR-2 induced motility, but not mechanical hypersensitivity in the rat colon.

PubMed

Suckow, S K; Anderson, E M; Caudle, R M

2012-03-01

Proteinase activated receptor 2 (PAR-2) is expressed by many neurons in the colon, including primary afferent neurons that co-express transient receptor potential vanilloid 1 (TRPV1). Activation of PAR-2 receptors was previously found to enhance colonic motility, increase secretion and produce hypersensitivity to mechanical stimuli. This study examined the functional role of TRPV1/PAR-2 expressing neurons that innervate the colon by lesioning TRPV1 bearing neurons with the highly selective and potent TRPV1 agonist resiniferatoxin. Colonic motility in response to PAR-2 activation was evaluated in vitro using isolated segments of descending colon and in vivo using manometry. Colonic mechanical nociceptive thresholds were measured using colorectal distension. Transient receptor potential vanilloid 1 expressing neurons were selectively lesioned with resiniferatoxin. In vitro, the PAR-2 agonists, trypsin and SLIGRL did not alter contractions of colon segments when applied alone, however, the agents enhanced acetylcholine stimulated contraction. In vivo, PAR-2 agonists administered intraluminally induced contractions of the colon and produced hypersensitivity to colorectal distention. The PAR-2 agonist enhancement of colonic contraction was eliminated when TRPV1 expressing neurons were lesioned with resiniferatoxin, but the PAR-2 agonist induced hypersensitivity remained in the lesioned animals. Our findings indicate that TRPV1/PAR-2 expressing primary afferent neurons mediate an extrinsic motor reflex pathway in the colon. These data, coupled with our previous studies, also indicate that the recently described colospinal afferent neurons are nociceptive, suggesting that these neurons may be useful targets for the pharmacological control of pain in diseases such as irritable bowel syndrome. © 2011 Blackwell Publishing Ltd.

Colonic luminal microbiota and bacterial metabolite composition in pregnant Huanjiang mini-pigs: effects of food composition at different times of pregnancy

PubMed Central

Kong, Xiang-feng; Ji, Yu-jiao; Li, Hua-wei; Zhu, Qian; Blachier, F.; Geng, Mei-mei; Chen, Wen; Yin, Yu-long

2016-01-01

The gut harbours diverse and complex microbiota, which influence body health including nutrient metabolism, immune development, and protection from pathogens. Pregnancy is associated with immune and metabolic changes that might be related to microbiota compositional dynamics. We therefore investigated the colonic luminal bacteria community in Huanjiang mini-pigs fed diets with different nutrient levels from the first to third trimester of pregnancy. The concentrations of intestinal metabolites including short-chain fat acids, NH3-N, indole, skatole, and bioamines were also determined. We found that the colonic bacteria species richness estimators (Chao1 and ACE) decreased with increased gestational age. The dominant phyla identified were Firmicutes and Bacteroidetes; the dominant genera were Lactobacillus, Treponema, Ruminococcus, Clostridium, and Prevotella. In addition, microbiota displayed spatial and temporal heterogeneity in composition, diversity, and species abundance in different colonic segments from the first to third trimester of pregnancy. Furthermore, the bacterial metabolites also changed according to the diet used and the pregnancy stage. These findings suggest that colonic bacteria richness decreased as gestational age increased, and that the higher nutrient level diet increased the production of metabolites related to nitrogen metabolism. However, although the higher nutrient diet was associated with pregnancy syndrome, causal links remain to be determined. PMID:27917879

Group B Streptococcal Colonization, Molecular Characteristics, and Epidemiology

PubMed Central

Shabayek, Sarah; Spellerberg, Barbara

2018-01-01

Streptococcus agalactiae or group B streptococcus (GBS) is a leading cause of serious neonatal infections. GBS is an opportunistic commensal constituting a part of the intestinal and vaginal physiologic flora and maternal colonization is the principal route of GBS transmission. GBS is a pathobiont that converts from the asymptomatic mucosal carriage state to a major bacterial pathogen causing severe invasive infections. At present, as many as 10 serotypes (Ia, Ib, and II–IX) are recognized. The aim of the current review is to shed new light on the latest epidemiological data and clonal distribution of GBS in addition to discussing the most important colonization determinants at a molecular level. The distribution and predominance of certain serotypes is susceptible to variations and can change over time. With the availability of multilocus sequence typing scheme (MLST) data, it became clear that GBS strains of certain clonal complexes possess a higher potential to cause invasive disease, while other harbor mainly colonizing strains. Colonization and persistence in different host niches is dependent on the adherence capacity of GBS to host cells and tissues. Bacterial biofilms represent well-known virulence factors with a vital role in persistence and chronic infections. In addition, GBS colonization, persistence, translocation, and invasion of host barriers are largely dependent on their adherence abilities to host cells and extracellular matrix proteins (ECM). Major adhesins mediating GBS interaction with host cells include the fibrinogen-binding proteins (Fbs), the laminin-binding protein (Lmb), the group B streptococcal C5a peptidase (ScpB), the streptococcal fibronectin binding protein A (SfbA), the GBS immunogenic bacterial adhesin (BibA), and the hypervirulent adhesin (HvgA). These adhesins facilitate persistent and intimate contacts between the bacterial cell and the host, while global virulence regulators play a major role in the transition to invasive

Determinants and Duration of Impact of Early Gut Bacterial Colonization.

PubMed

Edwards, Christine Ann

2017-01-01

An increasing number of studies show low diversity of the gut microbiome in those with chronic diseases such as obesity, inflammatory bowel disease, and allergy. Manipulation of the microbiota may promote health. However, the adult microbiota is stable and may be difficult to change. Understanding the fixed and modifiable factors, which determine colonization in early life, may provide strategies for acquisition of a health-promoting microbiome. Not enough is known about the long-term effects of established determinants of gut colonization, including delivery mode, perinatal antibiotics, and infant diet. It has been suggested that weaning onto solid diet containing non-digestible carbohydrates and cessation of breastfeeding are key stages in the colonization process. In addition, the microbiome of the placenta, amniotic fluid, and breast milk, alongside vaginal and fecal bacteria, may aid the transfer of maternal bacteria to the infant. However, methodological issues such as contamination during collection and/or analysis should be considered. Key Messages: The factors determining early colonization are becoming more evident. However, longitudinal studies of microbiome maturation into late childhood and adulthood are required. The nutrition and health status of the mother before, during, and after birth may be major factors in the early colonization of the infant. © 2017 S. Karger AG, Basel.

Amplification and sequence analysis of partial bacterial 16S ribosomal RNA gene in gallbladder bile from patients with primary biliary cirrhosis.

PubMed

Hiramatsu, K; Harada, K; Tsuneyama, K; Sasaki, M; Fujita, S; Hashimoto, T; Kaneko, S; Kobayashi, K; Nakanuma, Y

2000-07-01

The etiopathogenesis of bile duct lesion in primary biliary cirrhosis is unknown, though the participation of bacteria and/or their components and products is suspected. In this study, we tried to detect and identify bacteria in the bile of patients with primary biliary cirrhosis by polymerase chain reaction using universal bacterial primers of the 16S ribosomal RNA gene. Gallbladder bile samples from 15 patients with primary biliary cirrhosis, 5 with primary sclerosing cholangitis, 5 with hepatitis C virus-related liver cirrhosis, 11 with cholecystolithiasis, and from 12 normal adult gallbladders were used. In addition to the culture study, partial bacterial 16S ribosomal RNA gene was amplified by polymerase chain reaction (PCR) taking advantage of universal primers that can amplify the gene of almost all bacterial species, and the amplicons were cloned and sequenced. Sequence homology with specific bacterial species was analyzed by database research. Bacterial contamination at every step of the bile sampling, DNA extraction and PCR study was avoided. Furthermore, to confirm whether bacterial DNA is detectable in liver explants, the same analysis was performed using 10 liver explants of patients with primary biliary cirrhosis. In primary biliary cirrhosis, 75% (p<0.0001) of 100 clones were identified as so-called gram-positive cocci while these cocci were positive in only 5% in cholecystolithiasis (p<0.0001). In cholecystolithiasis gram-negative rods were predominant instead. One bacterial species detected in a normal adult was not related to those detected in primary biliary cirrhosis and cholecystolithiasis patients. No bacterial DNA was detected by PCR amplification in 10 liver explants of patients with primary biliary cirrhosis. The present results raise several possible roles of gram-positive bacteria in bile in the etiopathogenesis of primary biliary cirrhosis. However, these results could also reflect an epiphenomenon due to decreased bile flow in the

The impact of bacterial colonization on graft success after total pancreatectomy with autologous islet transplantation: considerations for early definitive surgical intervention.

PubMed

Jolissaint, Joshua S; Langman, Linda W; DeBolt, Claire L; Tatum, Jacob A; Martin, Allison N; Wang, Andrew Y; Strand, Daniel S; Zaydfudim, Victor M; Adams, Reid B; Brayman, Kenneth L

2016-11-01

The purpose of this study was to determine whether bacterial contamination of islets affects graft success after total pancreatectomy with islet autotransplantation (TPIAT). Factors associated with insulin independence after TPIAT are inconclusive. Although bacterial contamination does not preclude transplantation, the impact of bacterial contamination on graft success is unknown. Patients who received TPIAT at the University of Virginia between January 2007 and January 2016 were reviewed. Patient charts were reviewed for bacterial contamination and patients were prospectively contacted to assess rates of insulin independence. There was no significant difference in demographic or perioperative data between patients who achieved insulin independence and those who did not. However, six of 27 patients analyzed (22.2%) grew bacterial contaminants from culture of the final islet preparations. These patients had significantly lower islet yield and C-peptide at most recent follow-up (P<.05), and none of these patients achieved insulin independence. Islet transplant solutions are often culture positive, likely secondary to preprocurement pancreatic manipulation and introduction of enteric flora. Although autotransplantation of culture-positive islets is safe, it is associated with higher rates of graft failure and poor islet yield. Consideration should be given to identify patients who may develop refractory chronic pancreatitis and offer early operative management to prevent bacterial colonization. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Risk factors for lower urinary tract infection and bacterial stent colonization in patients with a double J ureteral stent.

PubMed

Akay, Ali Ferruh; Aflay, Uğur; Gedik, Abdullah; Sahin, Hayrettin; Bircan, Mehmet Kamuran

2007-01-01

We investigated the potential risk factors for lower urinary tract infection and bacterial stent colonization in patients with double-J stents. A total of 195 double-J stents from 190 patients (95 men and 95 women, mean age 40.22 years) were examined. In all patients, prophylactic antimicrobial therapy was administered at the time of stenting. The stents and urine samples were removed aseptically and the proximal and distal tip segments of the stents were obtained. Three culture specimens were obtained from each stent segment and urine sample. Chi-square tests, odds ratio, and relative risk were used for the statistical analysis. Bacterial colonies were found in 24% (47 of 190) of the urine samples, 31% (61 of 195) of the proximal stent segments, and 34% (67 of 195) of the distal stent segments. Of the pathogens identified, Escherichia coli (34 of 47) was the most common. Diabetes mellitus (P < 0.01), chronic renal failure (P < 0.001), and pregnancy (P < 0.01) were found to be risk factors for lower urinary tract infection in patients with stents. An increased stent colonization rate was associated with implantation time, age, and female sex, but these were not statistically significant for lower urinary tract infection Diabetes mellitus, chronic renal failure, and pregnancy are associated with a higher risk of lower urinary tract infection. Therefore, patients in these categories should be monitored carefully for infectious complications.

Metabolome progression during early gut microbial colonization of gnotobiotic mice

PubMed Central

Marcobal, Angela; Yusufaly, Tahir; Higginbottom, Steven; Snyder, Michael; Sonnenburg, Justin L.; Mias, George I.

2015-01-01

The microbiome has been implicated directly in host health, especially host metabolic processes and development of immune responses. These are particularly important in infants where the gut first begins being colonized, and such processes may be modeled in mice. In this investigation we follow longitudinally the urine metabolome of ex-germ-free mice, which are colonized with two bacterial species, Bacteroides thetaiotaomicron and Bifidobacterium longum. High-throughput mass spectrometry profiling of urine samples revealed dynamic changes in the metabolome makeup, associated with the gut bacterial colonization, enabled by our adaptation of non-linear time-series analysis to urine metabolomics data. Results demonstrate both gradual and punctuated changes in metabolite production and that early colonization events profoundly impact the nature of small molecules circulating in the host. The identified small molecules are implicated in amino acid and carbohydrate metabolic processes, and offer insights into the dynamic changes occurring during the colonization process, using high-throughput longitudinal methodology. PMID:26118551

Bacterial strategies of resistance to antimicrobial peptides.

PubMed

Joo, Hwang-Soo; Fu, Chih-Iung; Otto, Michael

2016-05-26

Antimicrobial peptides (AMPs) are a key component of the host's innate immune system, targeting invasive and colonizing bacteria. For successful survival and colonization of the host, bacteria have a series of mechanisms to interfere with AMP activity, and AMP resistance is intimately connected with the virulence potential of bacterial pathogens. In particular, because AMPs are considered as potential novel antimicrobial drugs, it is vital to understand bacterial AMP resistance mechanisms. This review gives a comparative overview of Gram-positive and Gram-negative bacterial strategies of resistance to various AMPs, such as repulsion or sequestration by bacterial surface structures, alteration of membrane charge or fluidity, degradation and removal by efflux pumps.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. © 2016 The Author(s).

Prospective survey of veterinary practitioners’ primary assessment of equine colic: clinical features, diagnoses, and treatment of 120 cases of large colon impaction

PubMed Central

2014-01-01

Background Large colon impactions are a common cause of colic in the horse. There are no scientific reports on the clinical presentation, diagnostic tests and treatments used in first opinion practice for large colon impaction cases. The aim of this study was to describe the presentation, diagnostic approach and treatment at the primary assessment of horses with large colon impactions. Methods Data were collected prospectively from veterinary practitioners on the primary assessment of equine colic cases over a 12 month period. Inclusion criteria were a diagnosis of primary large colon impaction and positive findings on rectal examination. Data recorded for each case included history, signalment, clinical and diagnostic findings, treatment on primary assessment and final case outcome. Case outcomes were categorised into three groups: simple medical (resolved with single treatment), complicated medical (resolved with multiple medical treatments) and critical (required surgery, were euthanased or died). Univariable analysis using one-way ANOVA and Tukey’s post-hoc test, Kruskal Wallis with Dunn’s post-hoc test and Chi squared analysis were used to compare between different outcome categories. Results 1032 colic cases were submitted by veterinary practitioners: 120 cases met the inclusion criteria for large colon impaction. Fifty three percent of cases were categorised as simple medical, 36.6% as complicated medical, and 9.2% as critical. Most cases (42.1%) occurred during the winter. Fifty nine percent of horses had had a recent change in management, 43% of horses were not ridden, and 12.5% had a recent / current musculoskeletal injury. Mean heart rate was 43bpm (range 26-88) and most cases showed mild signs of pain (67.5%) and reduced gut sounds (76%). Heart rate was significantly increased and gut sounds significantly decreased in critical compared to simple medical cases (p<0.05). Fifty different treatment combinations were used, with NSAIDs (93%) and oral

Inferior quantitative and qualitative immune responses to pneumococcal conjugate vaccine in infants with nasopharyngeal colonization by Streptococcus pneumoniae during the primary series of immunization.

PubMed

Madhi, Shabir A; Violari, Avy; Klugman, Keith P; Lin, Gina; McIntyre, James A; von Gottberg, Anne; Jean-Philippe, Patrick; Cotton, Mark F; Adrian, Peter

2011-09-16

Heightened immunogenicity, measured one month after the primary series of pneumococcal conjugate vaccine (PCV), in African children was previously hypothesized to be due to increased rates of nasopharyngeal pneumococcal colonization during early infancy. We analyzed the effect of selected vaccine-serotype (6B, 19F and 23F) nasopharyngeal colonization prior to the first PCV dose or when colonized for the first time prior to the second or third (2nd/3rd) PCV dose on serotype quantitative and qualitative antibody responses. Colonization prior to receiving the first PCV was associated with lower geometric mean antibody concentrations (GMCs) one month after the third dose of PCV and six months later to the colonizing-serotype. Colonized infants also had lower geometric mean titers (GMTs) on opsonophagocytosis activity assay (OPA) and a lower proportion had titers ≥ 8 against the colonizing serotypes (19F and 23F) post vaccination. Colonization occurring only prior to the 2nd/3rdPCV dose was also associated with lower GMCs and OPA GMTs to the colonizing-serotype. The effect of colonization with serotypes 19F and 23F prior to PCV vaccination had a greater effect on a lower proportion of colonized infants having OPA titers ≥ 8 than the effect of colonization on the lower proportion with antibody ≥ 0.35 μg/ml. Infant nasopharyngeal colonization at any stage before completing the primary series of PCV vaccination was associated with inferior quantitative and qualitative antibody responses to the colonizing-serotype. Copyright © 2011 Elsevier Ltd. All rights reserved.

Colonic metastasis from carcinoma of the breast that mimics a primary intestinal cancer.

PubMed

Uygun, Kazim; Kocak, Zafer; Altaner, Semsi; Cicin, Irfan; Tokatli, Fusun; Uzal, Cem

2006-08-31

Although the lung, liver, or bones are the most common location for distant metastases in breast cancer patients, metastases to the intestinal tract are very rarely recognized in the clinic. We will present an unusual case of colonic metastasis from a carcinoma of the breast that mimics a primary intestinal cancer, along with a through review of English language medical literature. Despite the fact that isolated gastrointestinal (GI) metastases are very rare and much less common than benign disease processes or second primaries of the intestinal tract in patients with a history of breast cancer, metastatic disease should be given consideration whenever a patient experiences GI symptoms.

Elevated methane levels in small intestinal bacterial overgrowth suggests delayed small bowel and colonic transit.

PubMed

Suri, Jaspreet; Kataria, Rahul; Malik, Zubair; Parkman, Henry P; Schey, Ron

2018-05-01

Limited research exists regarding the relationship between small intestinal bacterial overgrowth (SIBO), small bowel transit (SBT), and colonic transit (CT). Furthermore, symptom analysis is limited between the subtypes of SIBO: hydrogen producing (H-SIBO) and methane producing (M-SIBO). The primary aims of this study are to: compare the SBT and CT in patients with a positive lactulose breath test (LBT) to those with a normal study; compare the SBT and CT among patients with H-SIBO or M-SIBO; compare the severity of symptoms in patients with a positive LBT to those with a normal study; compare the severity of symptoms among patients with H-SIBO or M-SIBO.A retrospective review was performed for 89 patients who underwent a LBT and whole gut transit scintigraphy (WGTS) between 2014 and 2016. Seventy-eight patients were included. WGTS evaluated gastric emptying, SBT (normal ≥40% radiotracer bolus accumulated at the ileocecal valve at 6 hours), and CT (normal geometric center of colonic activity = 1.6-7.0 at 24 hours, 4.0-7.0 at 48 hours, 6.2-7.0 at 72 hours; elevated geometric center indicates increased transit). We also had patients complete a pretest symptom survey to evaluate nausea, bloating, constipation, diarrhea, belching, and flatulence.A total of 78 patients (69 females, 9 males, mean age of 48 years, mean BMI of 25.9) were evaluated. Forty-seven patients had a positive LBT (H-SIBO 66%, M-SIBO 34%). Comparison of SBT among patients with a positive LBT to normal LBT revealed no significant difference (62.1% vs 58.6%, P = .63). The mean accumulated radiotracer was higher for H-SIBO compared to M-SIBO (71.5% vs 44.1%; P < .05). For CT, all SIBO patients had no significant difference in geometric centers of colonic activity at 24, 48, and 72 hours when compared to the normal group. When subtyping, H-SIBO had significantly higher geometric centers compared to the M-SIBO group at 24 hours (4.4 vs 3.1, P < .001), 48 hours (5.2 vs 3

Bacterial flora of the sigmoid neovagina.

PubMed Central

Toolenaar, T A; Freundt, I; Wagenvoort, J H; Huikeshoven, F J; Vogel, M; Jeekel, H; Drogendijk, A C

1993-01-01

The bacterial microbiota of 15 sigmoid neovaginas, created in patients with congenital vaginal aplasia or male transsexualism, was studied. No specimen was sterile, and only normal inhabitants of the colon were cultured. The total counts of bacteria were lower than those reported for healthy sigmoid colons. PMID:8308126

Muc2 Protects against Lethal Infectious Colitis by Disassociating Pathogenic and Commensal Bacteria from the Colonic Mucosa

PubMed Central

Bergstrom, Kirk S. B.; Kissoon-Singh, Vanessa; Gibson, Deanna L.; Ma, Caixia; Montero, Marinieve; Sham, Ho Pan; Ryz, Natasha; Huang, Tina; Velcich, Anna; Finlay, B. Brett; Chadee, Kris; Vallance, Bruce A.

2010-01-01

Despite recent advances in our understanding of the pathogenesis of attaching and effacing (A/E) Escherichia coli infections, the mechanisms by which the host defends against these microbes are unclear. The goal of this study was to determine the role of goblet cell-derived Muc2, the major intestinal secretory mucin and primary component of the mucus layer, in host protection against A/E pathogens. To assess the role of Muc2 during A/E bacterial infections, we inoculated Muc2 deficient (Muc2−/−) mice with Citrobacter rodentium, a murine A/E pathogen related to diarrheagenic A/E E. coli. Unlike wildtype (WT) mice, infected Muc2−/− mice exhibited rapid weight loss and suffered up to 90% mortality. Stool plating demonstrated 10–100 fold greater C. rodentium burdens in Muc2−/− vs. WT mice, most of which were found to be loosely adherent to the colonic mucosa. Histology of Muc2−/− mice revealed ulceration in the colon amid focal bacterial microcolonies. Metabolic labeling of secreted mucins in the large intestine demonstrated that mucin secretion was markedly increased in WT mice during infection compared to uninfected controls, suggesting that the host uses increased mucin release to flush pathogens from the mucosal surface. Muc2 also impacted host-commensal interactions during infection, as FISH analysis revealed C. rodentium microcolonies contained numerous commensal microbes, which was not observed in WT mice. Orally administered FITC-Dextran and FISH staining showed significantly worsened intestinal barrier disruption in Muc2−/− vs. WT mice, with overt pathogen and commensal translocation into the Muc2−/− colonic mucosa. Interestingly, commensal depletion enhanced C. rodentium colonization of Muc2−/− mice, although colonic pathology was not significantly altered. In conclusion, Muc2 production is critical for host protection during A/E bacterial infections, by limiting overall pathogen and commensal numbers associated with the colonic

Impact of humic acids on the colonic microbiome in healthy volunteers.

PubMed

Swidsinski, Alexander; Dörffel, Yvonne; Loening-Baucke, Vera; Gille, Christoph; Reißhauer, Anne; Göktas, Onder; Krüger, Monika; Neuhaus, Jürgen; Schrödl, Wieland

2017-02-07

To test the effects of humic acids on innate microbial communities of the colon. We followed the effects of oral supplementation with humic acids (Activomin ® ) on concentrations and composition of colonic microbiome in 14 healthy volunteers for 45 d. 3 × 800 mg Activomin ® were taken orally for 10 d followed by 3 × 400 mg for 35 d. Colonic microbiota were investigated using multicolor fluorescence in situ hybridization (FISH) of Carnoy fixated and paraffin embedded stool cylinders. Two stool samples were collected a week prior to therapy and one stool sample on days 10, 31 and 45. Forty-one FISH probes representing different bacterial groups were used. The sum concentration of colonic microbiota increased from 20% at day 10 to 30% by day 31 and remained stable until day 45 (32%) of humic acid supplementation ( P < 0.001). The increase in the concentrations in each person was due to growth of preexisting groups. The individual microbial profile of the patients remained unchanged. Similarly, the bacterial diversity remained stable. Concentrations of 24 of the 35 substantial groups increased from 20% to 96%. Two bacterial groups detected with Bac303 ( Bacteroides ) and Myc657 (mycolic acid-containing Actinomycetes ) FISH probes decreased ( P > 0.05). The others remained unaffected. Bacterial groups with initially marginal concentrations (< 0.1 × 10 9 /mL) demonstrated no response to humic acids. The concentrations of pioneer groups of Bifidobacteriaceae , Enterobacteriaceae and Clostridium difficile increased but the observed differences were statistically not significant. Humic acids have a profound effect on healthy colonic microbiome and may be potentially interesting substances for the development of drugs that control the innate colonic microbiome.

Changes in bacterial community composition of Escherichia coli O157:H7 super-shedder cattle occur in the lower intestine.

PubMed

Zaheer, Rahat; Dugat-Bony, Eric; Holman, Devon; Cousteix, Elodie; Xu, Yong; Munns, Krysty; Selinger, Lorna J; Barbieri, Rutn; Alexander, Trevor; McAllister, Tim A; Selinger, L Brent

2017-01-01

Escherichia coli O157:H7 is a foodborne pathogen that colonizes ruminants. Cattle are considered the primary reservoir of E. coli O157:H7 with super-shedders, defined as individuals excreting > 104 E. coli O157:H7 CFU g-1 feces. The mechanisms leading to the super-shedding condition are largely unknown. Here, we used 16S rRNA gene pyrosequencing to examine the composition of the fecal bacterial community in order to investigate changes in the bacterial microbiota at several locations along the digestive tract (from the duodenum to the rectal-anal junction) in 5 steers previously identified as super-shedders and 5 non-shedders. The overall bacterial community structure did not differ by E. coli O157:H7 shedding status; but several differences in the relative abundance of taxa and OTUs were noted between the two groups. The genus Prevotella was most enriched in the non-shedders while the genus Ruminococcus and the Bacteroidetes phylum were notably enriched in the super-shedders. There was greater bacterial diversity and richness in samples collected from the lower- as compared to the upper gastrointestinal tract (GI). The spiral colon was the only GI location that differed in terms of bacterial diversity between super-shedders and non-shedders. These findings reinforced linkages between E. coli O157:H7 colonization in cattle and the nature of the microbial community inhabiting the digestive tract of super-shedders.

Changes in bacterial community composition of Escherichia coli O157:H7 super-shedder cattle occur in the lower intestine

PubMed Central

Cousteix, Elodie; Xu, Yong; Munns, Krysty; Selinger, Lorna J.; Barbieri, Rutn; Alexander, Trevor; McAllister, Tim A.; Selinger, L. Brent

2017-01-01

Escherichia coli O157:H7 is a foodborne pathogen that colonizes ruminants. Cattle are considered the primary reservoir of E. coli O157:H7 with super-shedders, defined as individuals excreting > 104 E. coli O157:H7 CFU g-1 feces. The mechanisms leading to the super-shedding condition are largely unknown. Here, we used 16S rRNA gene pyrosequencing to examine the composition of the fecal bacterial community in order to investigate changes in the bacterial microbiota at several locations along the digestive tract (from the duodenum to the rectal-anal junction) in 5 steers previously identified as super-shedders and 5 non-shedders. The overall bacterial community structure did not differ by E. coli O157:H7 shedding status; but several differences in the relative abundance of taxa and OTUs were noted between the two groups. The genus Prevotella was most enriched in the non-shedders while the genus Ruminococcus and the Bacteroidetes phylum were notably enriched in the super-shedders. There was greater bacterial diversity and richness in samples collected from the lower- as compared to the upper gastrointestinal tract (GI). The spiral colon was the only GI location that differed in terms of bacterial diversity between super-shedders and non-shedders. These findings reinforced linkages between E. coli O157:H7 colonization in cattle and the nature of the microbial community inhabiting the digestive tract of super-shedders. PMID:28141846

Bacterial colonization patterns in daily chlorhexidine care at the exit site in peritoneal dialysis patients-A prospective, randomized controlled trial.

PubMed

Wang, Hsi-Hao; Hung, Shih-Yuan; Chang, Min-Yu; Lee, Yi-Che; Lin, Hsiu-Fang; Lin, Tsun-Mei; Yang, Su-Pen; Lin, Hsi-Hsun; Yang, Su-Ching; Wang, Jiun-Ling

2017-01-01

Bacterial colonization patterns in daily chlorhexidine care at the exit site in peritoneal dialysis (PD) patients were not known. We performed a prospective, randomized controlled trial enrolling 89 PD patients. After stratification by initial Staphylococcus aureus (SA) carrier status, patients were randomly assigned to receive daily 4% chlorhexidine care (intervention group) or normal saline (control group) at the exit site. Monthly, we cultured bacteria from the exit site and nasal swabs for 1 year. The SA colonization rates at exit site at 6 and 12 months were significantly lower in the intervention group than the control group (5.0% vs. 22.9%, p = 0.023 and 8.6% vs. 28.1%, p = 0.037 for 6 and 12 months, respectively). The Methicillin-resistant SA (MRSA) colonization rate at exit site at 6 months was similar (5.7% vs. 2.5%,p = 0.596) in control and intervention group, but significantly lower in the intervention group than the control group at exit site at 12months (0% vs. 12.5%, p = 0.047). The gram-negative bacilli (GNB) colonization rates were similar between the intervention and control groups at 6 and 12 months. Genotyping of all MRSA isolates showed ST (sequence type) 59 was the most predominant clone. In conclusion, chlorhexidine care at the exit site in PD patients may be a good strategy for SA and MRSA decolonization. ClinicalTrials.gov NCT02446158.

Unusual primary HIV infection with colonic ulcer complicated by hemorrhagic shock: a case report

PubMed Central

2010-01-01

Introduction Timely diagnosis of primary HIV infection is important to prevent further transmission of HIV. Primary HIV infection may take place without symptoms or may be associated with fever, pharyngitis or headache. Sometimes, the clinical presentation includes aseptic meningitis or cutaneous lesions. Intestinal ulceration due to opportunistic pathogens (cytomegalovirus, Epstein-Barr virus, Toxoplasma gondii) has been described in patients with AIDS. However, although invasion of intestinal lymphoid tissue is a prominent feature of human and simian lentivirus infections, colonic ulceration has not been reported in acute HIV infection. Case description A 42-year-old Caucasian man was treated with amoxicillin-clavulanate for pharyngitis. He did not improve, and a rash developed. History taking revealed a negative HIV antibody test five months previously and unprotected sex with a male partner the month before admission. Repeated tests revealed primary HIV infection with an exceptionally high HIV-1 RNA plasma concentration (3.6 × 107 copies/mL) and a low CD4 count (101 cells/mm3, seven percent of total lymphocytes). While being investigated, the patient had a life-threatening hematochezia. After angiographic occlusion of a branch of the ileocaecal artery and initiation of antiretroviral therapy, the patient became rapidly asymptomatic and could be discharged. Colonoscopy revealed a bleeding colonic ulcer. We were unable to identify an etiology other than HIV for this ulcer. Conclusion This case adds to the known protean manifestation of primary HIV infection. The lack of an alternative etiology, despite extensive investigations, suggests that this ulcer was directly caused by primary HIV infection. This conclusion is supported by the well-described extensive loss of intestinal mucosal CD4+ T cells associated with primary HIV infection, the extremely high HIV viral load observed in our patient, and the rapid improvement of the ulcer after initiation of highly

Ecology of root colonizing Massilia (Oxalobacteraceae).

PubMed

Ofek, Maya; Hadar, Yitzhak; Minz, Dror

2012-01-01

Ecologically meaningful classification of bacterial populations is essential for understanding the structure and function of bacterial communities. As in soils, the ecological strategy of the majority of root-colonizing bacteria is mostly unknown. Among those are Massilia (Oxalobacteraceae), a major group of rhizosphere and root colonizing bacteria of many plant species. The ecology of Massilia was explored in cucumber root and seed, and compared to that of Agrobacterium population, using culture-independent tools, including DNA-based pyrosequencing, fluorescence in situ hybridization and quantitative real-time PCR. Seed- and root-colonizing Massilia were primarily affiliated with other members of the genus described in soil and rhizosphere. Massilia colonized and proliferated on the seed coat, radicle, roots, and also on hyphae of phytopathogenic Pythium aphanidermatum infecting seeds. High variation in Massilia abundance was found in relation to plant developmental stage, along with sensitivity to plant growth medium modification (amendment with organic matter) and potential competitors. Massilia absolute abundance and relative abundance (dominance) were positively related, and peaked (up to 85%) at early stages of succession of the root microbiome. In comparison, variation in abundance of Agrobacterium was moderate and their dominance increased at later stages of succession. In accordance with contemporary models for microbial ecology classification, copiotrophic and competition-sensitive root colonization by Massilia is suggested. These bacteria exploit, in a transient way, a window of opportunity within the succession of communities within this niche.

Ecology of Root Colonizing Massilia (Oxalobacteraceae)

PubMed Central

Ofek, Maya; Hadar, Yitzhak; Minz, Dror

2012-01-01

Background Ecologically meaningful classification of bacterial populations is essential for understanding the structure and function of bacterial communities. As in soils, the ecological strategy of the majority of root-colonizing bacteria is mostly unknown. Among those are Massilia (Oxalobacteraceae), a major group of rhizosphere and root colonizing bacteria of many plant species. Methodology/Principal Findings The ecology of Massilia was explored in cucumber root and seed, and compared to that of Agrobacterium population, using culture-independent tools, including DNA-based pyrosequencing, fluorescence in situ hybridization and quantitative real-time PCR. Seed- and root-colonizing Massilia were primarily affiliated with other members of the genus described in soil and rhizosphere. Massilia colonized and proliferated on the seed coat, radicle, roots, and also on hyphae of phytopathogenic Pythium aphanidermatum infecting seeds. High variation in Massilia abundance was found in relation to plant developmental stage, along with sensitivity to plant growth medium modification (amendment with organic matter) and potential competitors. Massilia absolute abundance and relative abundance (dominance) were positively related, and peaked (up to 85%) at early stages of succession of the root microbiome. In comparison, variation in abundance of Agrobacterium was moderate and their dominance increased at later stages of succession. Conclusions In accordance with contemporary models for microbial ecology classification, copiotrophic and competition-sensitive root colonization by Massilia is suggested. These bacteria exploit, in a transient way, a window of opportunity within the succession of communities within this niche. PMID:22808103

Interplay between the Gastric Bacterial Microbiota and Candida albicans during Postantibiotic Recolonization and Gastritis

PubMed Central

Mason, Katie L.; Erb Downward, John R.; Falkowski, Nicole R.; Young, Vincent B.; Kao, John Y.

2012-01-01

The indigenous bacterial microbiome of the stomach, including lactobacilli, is vital in promoting colonization resistance against Candida albicans. However, there are gaps in our understanding about C. albicans gastric colonization versus disease, especially during the postantibiotic recovery phase. This study compared the gastric responses to C. albicans strains CHN1 and SC5314 in microbiome-disturbed and germfree mice to elucidate the contribution of the indigenous microbiota in C. albicans colonization versus disease and yeast-bacterium antagonism during the post-cefoperazone recolonization period. C. albicans can prevent the regrowth of Lactobacillus spp. in the stomach after cefoperazone and promote increased colonization by Enterococcus spp. Using a culture-independent analysis, the effects of oral cefoperazone on the gastric bacterial microbiota were observed to last at least 3 weeks after the cessation of the antibiotic. Disturbance of the gastric bacterial community by cefoperazone alone was not sufficient to cause gastritis, C. albicans colonization was also needed. Gastritis was not evident until after day 7 in cefoperazone-treated infected mice. In contrast, in germfree mice which lack a gastric microbiota, C. albicans induced gastric inflammation within 1 week of inoculation. Therefore, the gastric bacterial community in cefoperazone-treated mice during the first week of postantibiotic recolonization was sufficient to prevent the development of gastritis, despite being ineffective at conferring colonization resistance against C. albicans. Altogether, these data implicate a dichotomy between C. albicans colonization and gastric disease that is bacterial microbiome dependent. PMID:21986629

Interplay between the gastric bacterial microbiota and Candida albicans during postantibiotic recolonization and gastritis.

PubMed

Mason, Katie L; Erb Downward, John R; Falkowski, Nicole R; Young, Vincent B; Kao, John Y; Huffnagle, Gary B

2012-01-01

The indigenous bacterial microbiome of the stomach, including lactobacilli, is vital in promoting colonization resistance against Candida albicans. However, there are gaps in our understanding about C. albicans gastric colonization versus disease, especially during the postantibiotic recovery phase. This study compared the gastric responses to C. albicans strains CHN1 and SC5314 in microbiome-disturbed and germfree mice to elucidate the contribution of the indigenous microbiota in C. albicans colonization versus disease and yeast-bacterium antagonism during the post-cefoperazone recolonization period. C. albicans can prevent the regrowth of Lactobacillus spp. in the stomach after cefoperazone and promote increased colonization by Enterococcus spp. Using a culture-independent analysis, the effects of oral cefoperazone on the gastric bacterial microbiota were observed to last at least 3 weeks after the cessation of the antibiotic. Disturbance of the gastric bacterial community by cefoperazone alone was not sufficient to cause gastritis, C. albicans colonization was also needed. Gastritis was not evident until after day 7 in cefoperazone-treated infected mice. In contrast, in germfree mice which lack a gastric microbiota, C. albicans induced gastric inflammation within 1 week of inoculation. Therefore, the gastric bacterial community in cefoperazone-treated mice during the first week of postantibiotic recolonization was sufficient to prevent the development of gastritis, despite being ineffective at conferring colonization resistance against C. albicans. Altogether, these data implicate a dichotomy between C. albicans colonization and gastric disease that is bacterial microbiome dependent.

Spatial and temporal features of the growth of a bacterial species colonizing the zebrafish gut.

PubMed

Jemielita, Matthew; Taormina, Michael J; Burns, Adam R; Hampton, Jennifer S; Rolig, Annah S; Guillemin, Karen; Parthasarathy, Raghuveer

2014-12-16

, to visualize for the first time the colonization of a live, vertebrate gut by specific bacteria with sufficient resolution to quantify the population over a range from a few individuals to tens of thousands of bacterial cells. Our results provide unprecedented measures of bacterial growth kinetics and also show the influence of spatial structure on bacterial populations, which can be revealed only by direct imaging. Copyright © 2014 Jemielita et al.

Bacterial interactions in dental biofilm development.

PubMed

Hojo, K; Nagaoka, S; Ohshima, T; Maeda, N

2009-11-01

Recent analyses with ribosomal RNA-based technologies have revealed the diversity of bacterial populations within dental biofilms, and have highlighted their important contributions to oral health and disease. Dental biofilms are exceedingly complex and multispecies ecosystems, where oral bacteria interact cooperatively or competitively with other members. Bacterial interactions that influence dental biofilm communities include various different mechanisms. During the early stage of biofilm formation, it is known that planktonic bacterial cells directly attach to surfaces of the oral cavity or indirectly bind to other bacterial cells that have already colonized. Adherence through co-aggregation may be critical for the temporary retention of bacteria on dental surfaces, and may facilitate eventual bacterial colonization. It is likely that metabolic communication, genetic exchange, production of inhibitory factors (e.g., bacteriocins, hydrogen peroxide, etc.), and quorum-sensing are pivotal regulatory factors that determine the bacterial composition and/or metabolism. Since each bacterium can easily access a neighboring bacterial cell and its metabolites, genetic exchanges and metabolic communication may occur frequently in dental biofilms. Quorum-sensing is defined as gene regulation in response to cell density, which influences various functions, e.g., virulence and bacteriocin production. In this review, we discuss these important interactions among oral bacteria within the dental biofilm communities.

Impact of humic acids on the colonic microbiome in healthy volunteers

PubMed Central

Swidsinski, Alexander; Dörffel, Yvonne; Loening-Baucke, Vera; Gille, Christoph; Reißhauer, Anne; Göktas, Onder; Krüger, Monika; Neuhaus, Jürgen; Schrödl, Wieland

2017-01-01

AIM To test the effects of humic acids on innate microbial communities of the colon. METHODS We followed the effects of oral supplementation with humic acids (Activomin®) on concentrations and composition of colonic microbiome in 14 healthy volunteers for 45 d. 3 × 800 mg Activomin® were taken orally for 10 d followed by 3 × 400 mg for 35 d. Colonic microbiota were investigated using multicolor fluorescence in situ hybridization (FISH) of Carnoy fixated and paraffin embedded stool cylinders. Two stool samples were collected a week prior to therapy and one stool sample on days 10, 31 and 45. Forty-one FISH probes representing different bacterial groups were used. RESULTS The sum concentration of colonic microbiota increased from 20% at day 10 to 30% by day 31 and remained stable until day 45 (32%) of humic acid supplementation (P < 0.001). The increase in the concentrations in each person was due to growth of preexisting groups. The individual microbial profile of the patients remained unchanged. Similarly, the bacterial diversity remained stable. Concentrations of 24 of the 35 substantial groups increased from 20% to 96%. Two bacterial groups detected with Bac303 (Bacteroides) and Myc657 (mycolic acid-containing Actinomycetes) FISH probes decreased (P > 0.05). The others remained unaffected. Bacterial groups with initially marginal concentrations (< 0.1 × 109/mL) demonstrated no response to humic acids. The concentrations of pioneer groups of Bifidobacteriaceae, Enterobacteriaceae and Clostridium difficile increased but the observed differences were statistically not significant. CONCLUSION Humic acids have a profound effect on healthy colonic microbiome and may be potentially interesting substances for the development of drugs that control the innate colonic microbiome. PMID:28223733

Palliative chemotherapy among people living in poverty with metastasised colon cancer: facilitation by primary care and health insurance.

PubMed

Gorey, Kevin M; Bartfay, Emma; Kanjeekal, Sindu M; Wright, Frances C; Hamm, Caroline; Luginaah, Isaac N; Zou, Guangyong; Holowaty, Eric J; Richter, Nancy L; Balagurusamy, Madhan K

2016-08-23

Many Americans with metastasised colon cancer do not receive indicated palliative chemotherapy. We examined the effects of health insurance and physician supplies on such chemotherapy in California. We analysed registry data for 1199 people with metastasised colon cancer diagnosed between 1996 and 2000 and followed for 1 year. We obtained data on health insurance, census tract-based socioeconomic status and county-level physician supplies. Poor neighbourhoods were oversampled and the criterion was receipt of chemotherapy. Effects were described with rate ratios (RR) and tested with logistic regression models. Palliative chemotherapy was received by less than half of the participants (45%). Facilitating effects of primary care (RR=1.23) and health insurance (RR=1.14) as well as an impeding effect of specialised care (RR=0.86) were observed. Primary care physician (PCP) supply took precedence. Adjusting for poverty, PCP supply was the only significant and strong predictor of chemotherapy (OR=1.62, 95% CI 1.02 to 2.56). The threshold for this primary care advantage was realised in communities with 8.5 or more PCPs per 10 000 inhabitants. Only 10% of participants lived in such well-supplied communities. This study's observations of facilitating effects of primary care and health insurance on palliative chemotherapy for metastasised colon cancer clearly suggested a way to maximise Affordable Care Act (ACA) protections. Strengthening America's system of primary care will probably be the best way to ensure that the ACA's full benefits are realised. Such would go a long way towards facilitating access to palliative care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Using Bayesian modelling to investigate factors governing antibiotic-induced Candida albicans colonization of the GI tract

PubMed Central

Shankar, Jyoti; Solis, Norma V.; Mounaud, Stephanie; Szpakowski, Sebastian; Liu, Hong; Losada, Liliana; Nierman, William C.; Filler, Scott G.

2015-01-01

Receipt of broad-spectrum antibiotics enhances Candida albicans colonization of the GI tract, a risk factor for haematogenously-disseminated candidiasis. To understand how antibiotics influence C. albicans colonization, we treated mice orally with vancomycin or a combination of penicillin, streptomycin, and gentamicin (PSG) and then inoculated them with C. albicans by gavage. Only PSG treatment resulted in sustained, high-level GI colonization with C. albicans. Furthermore, PSG reduced bacterial diversity in the colon much more than vancomycin. Both antibiotic regimens significantly reduced IL-17A, IL-21, IL-22 and IFN-γ mRNA levels in the terminal ileum but had limited effect on the GI fungal microbiome. Through a series of models that employed Bayesian model averaging, we investigated the associations between antibiotic treatment, GI microbiota, and host immune response and their collective impact on C. albicans colonization. Our analysis revealed that bacterial genera were typically associated with either C. albicans colonization or altered cytokine expression but not with both. The only exception was Veillonella, which was associated with both increased C. albicans colonization and reduced IL-21 expression. Overall, antibiotic-induced changes in the bacterial microbiome were much more consistent determinants of C. albicans colonization than either the GI fungal microbiota or the GI immune response. PMID:25644850

Mucosal colonization by metastatic carcinoma in the gastrointestinal tract: a potential mimic of primary neoplasia.

PubMed

Estrella, Jeannelyn S; Wu, Tsung-Teh; Rashid, Asif; Abraham, Susan C

2011-04-01

The gastrointestinal (GI) tract is a common site for both primary and metastatic carcinomas. Distinguishing the two can occasionally be difficult, particularly when metastatic tumor reaches the mucosal surface. Features that are typically used to make this distinction include the presence of an adenomatous precursor lesion, regional lymph node involvement, and gross configuration of the tumor. However, we recently encountered 2 index cases of metastatic carcinoma in the small intestine (1 from the colorectum and 1 of endocervical origin) that were initially misinterpreted as primary small bowel carcinomas because of apparent in situ growth in the mucosal surface resembling polypoid, adenomatous precursor lesions. We, therefore, studied 100 GI resections from 1987 to 2009 that were reported to show mucosal involvement by metastatic carcinoma, and compared the histologic features with a control group of 29 primary small bowel adenocarcinomas. Gross descriptions and histologic sections were evaluated for the following: (1) tumor spread along an intact basement membrane of villi/crypts (mucosal colonization), (2) resemblance to an adenoma/precursor lesion, (3) gross configuration of the tumor, (4) lymphovascular invasion, and (5) regional lymph node involvement in the metastatic site. Metastatic sites included the small intestine (n=74), colorectum (n=16), or both (n=10). Primary tumors were GI (n=55, with 47 from colorectum), gynecologic (n=28), pulmonary (n=8), genitourinary (n=6), head and neck (n=2), and breast (n=1). Overall, 42 (42%) of the metastases that reached the mucosal surface of the bowel showed at least focal mucosal colonization, 26% resembled a precursor adenoma, 62% had regional lymph node positivity, and only 24% cases showed a classic serosal-based configuration. In 4 cases (2 of GI origin and 2 of gynecologic origin), metastatic tumors were initially interpreted as new primaries by the pathologist (n=2) or clinicians (n=2). Metastatic carcinomas

Bacterial colonization of the ovarian bursa in dogs with clinically suspected pyometra and in controls.

PubMed

Rubio, Alejandro; Boyen, Filip; Tas, Olaf; Kitshoff, Adriaan; Polis, Ingeborgh; Van Goethem, Bart; de Rooster, Hilde

2014-10-15

Septic peritonitis occurs relatively commonly in dogs. Secondary septic peritonitis is usually associated with perforation of intestines or infected viscera, such as the uterus in pyometra cases. The aim of this study was to evaluate the bacterial flora in the ovarian bursae of intact bitches as a potential source of contamination. One hundred forty dogs, clinically suspected of pyometra, were prospectively enrolled. The control group consisted of 26 dogs that underwent elective ovariohysterectomies and 18 dogs with mammary gland tumors that were neutered at the time of mastectomy. Bacteriology samples were taken aseptically at the time of surgery from the bursae and the uterus in all dogs. Twenty-two dogs that were clinically suspected of pyometra had sterile uterine content ("mucometra" cases); the remaining 118 had positive uterine cultures ("pyometra" cases) and septic peritoneal fluid was present in 10% of these cases. Of the 118 pyometra cases, 9 had unilateral and 15 had bilateral bacterial colonization of their ovarian bursae. However, the bacteria from the ovarian bursa were similar to those recovered from the uterine pus in only half of the cases. Furthermore, positive bursae were also seen in one mucometra dog (unilateral) and in four control dogs (two unilateral and two bilateral). The data illustrate that the canine ovarian bursa can harbor bacteria. The biological importance of these isolations remains unclear. Copyright © 2014 Elsevier Inc. All rights reserved.

Propionibacterium acnes in primary shoulder arthroplasty: rates of colonization, patient risk factors, and efficacy of perioperative prophylaxis.

PubMed

Koh, Chuan Kong; Marsh, Jonathan P; Drinković, Dragana; Walker, Cameron G; Poon, Peter C

2016-05-01

Recent literature has shown that Propionibacterium acnes can be cultured from superficial and deep layers of the shoulder. Our aims were to assess the rate of P. acnes colonization in patients undergoing primary shoulder arthroplasty, to identify patient-related risk factors, and to evaluate the efficacy of our perioperative antisepsis protocol. Thirty consecutive patients undergoing primary shoulder arthroplasty were included in our study. Swabs were taken perioperatively (4 superficial and 2 deep wound swabs) and analyzed quantitatively for P. acnes. Cefazolin minimum inhibitory concentration was determined for P. acnes isolates from positive deep cultures. Twenty-two patients (73%) had positive cultures for P. acnes. Male gender (P = .024) and presence of hair (P = .005) had significantly higher rates of P. acnes superficial cultures. Subjects with positive superficial P. acnes cultures (P = .076) and presence of hair with a history of steroid injection (P = .092) were more likely to have deep P. acnes-positive cultures, but this was not statistically significant. Local topical antisepsis measures did not eradicate P. acnes (P = .12). Mean cefazolin minimum inhibitory concentration for P. acnes was 0.32 μg/mL. P. acnes is commonly isolated from the skin and deep surgical wounds of patients undergoing primary total shoulder arthroplasty who have not had previous shoulder surgery. Male gender and presence of hair were significant risk factors for P. acnes colonization. Perioperative local topical antisepsis and cefazolin administration were not effective in eliminating P. acnes colonization. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Traumatic colon injuries -- factors that influence surgical management.

PubMed

Jinescu, G; Lica, I; Beuran, M

2013-01-01

This study sought to evaluate current trends in surgical management of colon injuries in a level I urban trauma centre, in the light of our increasing confidence in primary repair. Our retrospective study evaluates the results of 116 patients with colon injuries operated at Bucharest Clinical Emergency Hospital, in the light of some of the most commonly cited factors which could influence the surgeon decision-making process towards primary repair or colostomy. Blunt injuries were more common than penetrating injuries (65% vs. 31%). Significant other injuries occurred in 85 (73%) patients. Primary repair was performed in 95 patients (82%). Fecal diversion was used in 21 patients(18%). Multiple factors influence the decision-making process: shock, fecal contamination, associated injuries and higher scores on the Abdominal Trauma Index (ATI) and Colon Injury Scale (CIS). Colon related intra-abdominal complications occurred in 7% of patients in whom the colon injury was closed primarily and in 14% of patients in whom a stoma was created, ATI having a predictive role in their occurrence. The overall mortality rate was 19%. Primary repair of colon injuries, either by primary suture or resection and anastomosis, is a safe method in the management of the majority of colonic injuries. Colostomy is preferred for patients with ATI ≥ 30 and CIS ≥ 4. Surgical judgment remains the final arbiter in decision making. Celsius.

General and specialized media routinely employed for primary isolation of bacterial pathogens of fishes

USGS Publications Warehouse

Starliper, C.E.

2008-01-01

There are a number of significant diseases among cultured and free-ranging freshwater fishes that have a bacterial etiology; these represent a variety of gram-negative and gram-positive genera. Confirmatory diagnosis of these diseases involves primary isolation of the causative bacterium on bacteriologic media. Frequently used "general" bacteriologic media simply provide the essential nutrients for growth. For most of the major pathogens, however, there are differential and/or selective media that facilitate primary recovery. Some specialized media are available as "ready-to-use" from suppliers, while others must be prepared. Differential media employ various types of indicator systems, such as pH indicators, that allow diagnosticians to observe assimilation of selected substrates. An advantage to the use of differential media for primary isolation is that they hasten bacterial characterization by yielding the appropriate positive or negative result for a particular substrate, often leading to a presumptive identification. Selective media also incorporate agent(s) that inhibit the growth of contaminants typically encountered with samples from aquatic environments. Media that incorporate differential and/or selective components are ideally based on characters that are unique to the targeted bacterium, and their use can reduce the time associated with diagnosis and facilitate early intervention in affected fish populations. In this review, the concepts of general and differential/selective bacteriologic media and their use and development for fish pathogens are discussed. The media routinely employed for primary isolation of the significant bacterial pathogens of fishes are presented. ?? Wildlife Disease Association 2008.

Bacterial desorption from food container and food processing surfaces.

PubMed

McEldowney, S; Fletcher, M

1988-03-01

The desorption ofStaphylococcus aureus, Acinetobacter calcoaceticus, and a coryneform from the surfaces of materials used for manufacturing food containers (glass, tin plate, and polypropylene) or postprocess canning factory conveyor belts (stainless steel and nylon) was investigated. The effect of time, pH, temperature, and adsorbed organic layers on desorption was studied.S. aureus did not detach from the substrata at any pH investigated (between pH 5 and 9).A. calcoaceticus and the coryneform in some cases detached, depending upon pH and substratum composition. The degree of bacterial detachment from the substrata was not related to bacterial respiration at experimental pH values. Bacterial desorption was not affected by temperature (4-30°C) nor by an adsorbed layer of peptone and yeast extract on the substrata. The results indicate that bacterial desorption, hence bacterial removal during cleaning or their transfer via liquids flowing over colonized surfaces, is likely to vary with the surface composition and the bacterial species colonizing the surfaces.

Phase 2a study assessing colonization efficiency, safety, and acceptability of Lactobacillus crispatus CTV-05 in women with bacterial vaginosis.

PubMed

Hemmerling, Anke; Harrison, William; Schroeder, Adrienne; Park, Jeanna; Korn, Abner; Shiboski, Stephen; Foster-Rosales, Anne; Cohen, Craig R

2010-12-01

Bacterial vaginosis (BV) is a common vaginal infection caused by a lack of endogenous lactobacilli and overgrowth of pathogens that frequently recurs following antibiotic treatment. A phase 2a study assessed colonization efficiency, safety, tolerability, and acceptability of Lactobacillus crispatus CTV-05 (LACTIN-V) administered by a vaginal applicator. Twenty-four women with BV were randomized in a 3:1 ratio of active product to placebo. Participants used LACTIN-V at 2 × 10 colony-forming units (cfu)/dose or placebo for 5 initial consecutive days, followed by a weekly application over 2 weeks. They returned for follow-up on Days 10 and 28. Sixty-one percent of the 18 women randomized to the LACTIN-V group were colonized with L. crispatus CTV-05 at Day 10 or Day 28. Among LACTIN-V users with complete adherence to the study regimen, 78% were colonized at Day 10 or Day 28. Of the 120 adverse events (AEs) that occurred, 108 (90%) and 12 (10%) were of mild and moderate severity, respectively. AEs were evenly distributed between the LACTIN-V and placebo group. Of the total AEs, 93 (78%) were genitourinary in origin. The most common genitourinary AEs included vaginal discharge (46%), abdominal pain (46%), dysuria (21%), pollakiuria (21%), vaginal odor (21%), and genital pruritus (17%). No grade 3 or 4 AEs or serious AEs occurred and no deep epithelial disruption was seen during colposcopic evaluation. The product was well tolerated and accepted. LACTIN-V colonized well, and was safe and acceptable in women treated for BV.

Specific Fluorescence in Situ Hybridization (FISH) Test to Highlight Colonization of Xylem Vessels by Xylella fastidiosa in Naturally Infected Olive Trees (Olea europaea L.)

PubMed Central

Cardinale, Massimiliano; Luvisi, Andrea; Meyer, Joana B.; Sabella, Erika; De Bellis, Luigi; Cruz, Albert C.; Ampatzidis, Yiannis; Cherubini, Paolo

2018-01-01

The colonization behavior of the Xylella fastidiosa strain CoDiRO, the causal agent of olive quick decline syndrome (OQDS), within the xylem of Olea europaea L. is still quite controversial. As previous literature suggests, even if xylem vessel occlusions in naturally infected olive plants were observed, cell aggregation in the formation of occlusions had a minimal role. This observation left some open questions about the whole behavior of the CoDiRO strain and its actual role in OQDS pathogenesis. In order to evaluate the extent of bacterial infection in olive trees and the role of bacterial aggregates in vessel occlusions, we tested a specific fluorescence in situ hybridization (FISH) probe (KO 210) for X. fastidiosa and quantified the level of infection and vessel occlusion in both petioles and branches of naturally infected and non-infected olive trees. All symptomatic petioles showed colonization by X. fastidiosa, especially in the larger innermost vessels. In several cases, the vessels appeared completely occluded by a biofilm containing bacterial cells and extracellular matrix and the frequent colonization of adjacent vessels suggested a horizontal movement of the bacteria. Infected symptomatic trees had 21.6 ± 10.7% of petiole vessels colonized by the pathogen, indicating an irregular distribution in olive tree xylem. Thus, our observations point out the primary role of the pathogen in olive vessel occlusions. Furthermore, our findings indicate that the KO 210 FISH probe is suitable for the specific detection of X. fastidiosa. PMID:29681910

Colonic transit time is related to bacterial metabolism and mucosal turnover in the gut.

PubMed

Roager, Henrik M; Hansen, Lea B S; Bahl, Martin I; Frandsen, Henrik L; Carvalho, Vera; Gøbel, Rikke J; Dalgaard, Marlene D; Plichta, Damian R; Sparholt, Morten H; Vestergaard, Henrik; Hansen, Torben; Sicheritz-Pontén, Thomas; Nielsen, H Bjørn; Pedersen, Oluf; Lauritzen, Lotte; Kristensen, Mette; Gupta, Ramneek; Licht, Tine R

2016-06-27

Little is known about how colonic transit time relates to human colonic metabolism and its importance for host health, although a firm stool consistency, a proxy for a long colonic transit time, has recently been positively associated with gut microbial richness. Here, we show that colonic transit time in humans, assessed using radio-opaque markers, is associated with overall gut microbial composition, diversity and metabolism. We find that a long colonic transit time associates with high microbial richness and is accompanied by a shift in colonic metabolism from carbohydrate fermentation to protein catabolism as reflected by higher urinary levels of potentially deleterious protein-derived metabolites. Additionally, shorter colonic transit time correlates with metabolites possibly reflecting increased renewal of the colonic mucosa. Together, this suggests that a high gut microbial richness does not per se imply a healthy gut microbial ecosystem and points at colonic transit time as a highly important factor to consider in microbiome and metabolomics studies.

Impact of experimental human pneumococcal carriage on nasopharyngeal bacterial densities in healthy adults.

PubMed

Shak, Joshua R; Cremers, Amelieke J H; Gritzfeld, Jenna F; de Jonge, Marien I; Hermans, Peter W M; Vidal, Jorge E; Klugman, Keith P; Gordon, Stephen B

2014-01-01

Colonization of the nasopharynx by Streptococcus pneumoniae is a necessary precursor to pneumococcal diseases that result in morbidity and mortality worldwide. The nasopharynx is also host to other bacterial species, including the common pathogens Staphylococcus aureus, Haemophilus influenzae, and Moraxella catarrhalis. To better understand how these bacteria change in relation to pneumococcal colonization, we used species-specific quantitative PCR to examine bacterial densities in 52 subjects 7 days before, and 2, 7, and 14 days after controlled inoculation of healthy human adults with S. pneumoniae serotype 6B. Overall, 33 (63%) of subjects carried S. pneumoniae post-inoculation. The baseline presence and density of S. aureus, H. influenzae, and M. catarrhalis were not statistically associated with likelihood of successful pneumococcal colonization at this study's sample size, although a lower rate of pneumococcal colonization in the presence of S. aureus (7/14) was seen compared to that in the presence of H. influenzae (12/16). Among subjects colonized with pneumococci, the number also carrying either H. influenzae or S. aureus fell during the study and at 14 days post-inoculation, the proportion carrying S. aureus was significantly lower among those who were colonized with S. pneumoniae (p = 0.008) compared to non-colonized subjects. These data on bacterial associations are the first to be reported surrounding experimental human pneumococcal colonization and show that co-colonizing effects are likely subtle rather than absolute.

Characterization of the gut bacterial community in Manduca sexta and effect of antibiotics on bacterial diversity and nematode reproduction.

PubMed

van der Hoeven, Ransome; Betrabet, Geeta; Forst, Steven

2008-09-01

The tobacco hornworm, Manduca sexta, is a model lepidopteran insect used to study the pathogenic and mutualistic phases of entomopathogenic nematodes (EPNs) and their bacterial symbionts. While intestinal microbial communities could potentially compete with the EPN and its bacterial partner for nutrient resources of the insect, the microbial gut community had not been characterized previously. Here, we show that the midgut of M. sexta raised on an artificial diet contained mostly Gram-positive cocci and coryneforms including Staphylococcus, Pediococcus, Micrococcus and Corynebacterium. Major perturbation in the gut community was observed on addition of antibiotics to the diet. Paenibacillus and several Proteobacteria such as Methylobacterium, Sphingomonas and Acinetobacter were primary genera identified under these conditions. Furthermore, the reproduction of the nematode Steinernema carpocapsae was less efficient, and the level of nematode colonization by its symbiont Xenorhabdus nematophila reduced, in insects reared on a diet containing antibiotics. The effect of antibiotics and perturbation of gut microbiota on nematode reproduction is discussed.

Chemical sensing in mammalian host-bacterial commensal associations

USDA-ARS?s Scientific Manuscript database

The mammalian gastrointestinal (GI) tract is colonized by a complex consortium of bacterial species. Bacteria engage in chemical signaling to coordinate population-wide behavior. However, it is unclear if chemical sensing plays a role in establishing mammalian host–bacterial commensal relationships....

Antibiotic-induced dysbiosis alters host-bacterial interactions and leads to colonic sensory and motor changes in mice

PubMed Central

Aguilera, M; Cerdà-Cuéllar, M; Martínez, V

2015-01-01

Alterations in the composition of the commensal microbiota (dysbiosis) seem to be a pathogenic component of functional gastrointestinal disorders, mainly irritable bowel syndrome (IBS), and might participate in the secretomotor and sensory alterations observed in these patients.We determined if a state antibiotics-induced intestinal dysbiosis is able to modify colonic pain-related and motor responses and characterized the neuro-immune mechanisms implicated in mice. A 2-week antibiotics treatment induced a colonic dysbiosis (increments in Bacteroides spp, Clostridium coccoides and Lactobacillus spp and reduction in Bifidobacterium spp). Bacterial adherence was not affected. Dysbiosis was associated with increased levels of secretory-IgA, up-regulation of the antimicrobial lectin RegIIIγ, and toll-like receptors (TLR) 4 and 7 and down-regulation of the antimicrobial-peptide Resistin-Like Molecule-β and TLR5. Dysbiotic mice showed less goblet cells, without changes in the thickness of the mucus layer. Neither macroscopical nor microscopical signs of inflammation were observed. In dysbiotic mice, expression of the cannabinoid receptor 2 was up-regulated, while the cannabinoid 1 and the mu-opioid receptors were down-regulated. In antibiotic-treated mice, visceral pain-related responses elicited by intraperitoneal acetic acid or intracolonic capsaicin were significantly attenuated. Colonic contractility was enhanced during dysbiosis. Intestinal dysbiosis induce changes in the innate intestinal immune system and modulate the expression of pain-related sensory systems, an effect associated with a reduction in visceral pain-related responses. Commensal microbiota modulates gut neuro-immune sensory systems, leading to functional changes, at least as it relates to viscerosensitivity. Similar mechanisms might explain the beneficial effects of antibiotics or certain probiotics in the treatment of IBS. PMID:25531553

Primary repair for pediatric colonic injury: Are there differences among adult and pediatric trauma centers?

PubMed

Khan, Muhammad; Jehan, Faisal; O'Keeffe, Terence; Pandit, Viraj; Kulvatunyou, Narong; Tang, Andrew; Gries, Lynn; Joseph, Bellal

2017-12-01

Management of colonic injuries (colostomy [CO] versus primary anastomosis [PA]) among pediatric patients remains controversial. The aim of this study was to assess outcomes in pediatric trauma patient with colonic injury undergoing operative intervention. The National Trauma Data Bank (2011-2012) was queried including patients with isolated colonic injury undergoing exploratory laparotomy with PA or CO with age ≤18 y. Missing value analysis was performed. Patients were stratified into two groups: PA and CO. Outcome measures were mortality, in-hospital complications, and hospital length of stay. Multivariate regression analysis was performed. A total of 1151 patients included. Mean ± standard deviation age was 11.61 ± 2.8 y, and median [IQR] Injury Severity Score was 12 [8-16]; 39% (n = 449) of the patients had CO, and 35.6% (n = 410) were managed in pediatric trauma centers (PC). Patients with CO had a higher Injury Severity Score (P < 0.001), a trend toward lower blood pressure (P = 0.40), and an older age (P < 0.001). There was no difference in mortality between the PA and CO groups. However, patients who underwent PA had a shorter length of stay (P < 0.001) and lower in-hospital complications (P < 0.001). A subanalysis shows that, after controlling for all confounding factors, patients managed in PC were 1.2 times (1.2 [1.1-2.1], P = 0.04) more likely to receive a CO than those patients managed in adult trauma centers (AC). Moreover, there was no difference in mortality between the AC and the PC (P = 0.79). Our data demonstrate no difference in mortality in pediatric trauma patients with colonic injury who undergo primary repair or CO. However, adult trauma centers had lower rates of CO performed as compared to a similar cohort of patients managed in pediatric trauma centers. Further assessment of the reasons underlying such differences will help improve patient outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnosis of primary ciliary dyskinesia*

PubMed Central

Olm, Mary Anne Kowal; Caldini, Elia Garcia; Mauad, Thais

2015-01-01

Primary ciliary dyskinesia (PCD) is a genetic disorder of ciliary structure or function. It results in mucus accumulation and bacterial colonization of the respiratory tract which leads to chronic upper and lower airway infections, organ laterality defects, and fertility problems. We review the respiratory signs and symptoms of PCD, as well as the screening tests for and diagnostic investigation of the disease, together with details related to ciliary function, ciliary ultrastructure, and genetic studies. In addition, we describe the difficulties in diagnosing PCD by means of transmission electron microscopy, as well as describing patient follow-up procedures. PMID:26176524

Previously unrecognized stages of species-specific colonization in the mutualism between Xenorhabdus bacteria and Steinernema nematodes

PubMed Central

Chaston, John M.; Murfin, Kristen E.; Heath-Heckman, Elizabeth A.; Goodrich-Blair, Heidi

2013-01-01

Summary The specificity of a horizontally transmitted microbial symbiosis is often defined by molecular communication between host and microbe during initial engagement, which can occur in discrete stages. In the symbiosis between Steinernema nematodes and Xenorhabdus bacteria, previous investigations focused on bacterial colonization of the intestinal lumen (receptacle) of the nematode infective juvenile (IJ), as this was the only known persistent, intimate, and species-specific contact between the two. Here we show that bacteria colonize the anterior intestinal cells of other nematode developmental stages in a species-specific manner. Also, we describe three processes that only occur in juveniles that are destined to become IJs. First, a few bacterial cells colonize the nematode pharyngeal-intestinal valve (PIV) anterior to the intestinal epithelium. Second, the nematode intestine constricts while bacteria initially remain in the PIV. Third, anterior intestinal constriction relaxes and colonizing bacteria occupy the receptacle. At each stage, colonization requires X. nematophila symbiosis region 1 (SR1) genes and is species-specific: X. szentirmaii, which naturally lacks SR1, does not colonize unless SR1 is ectopically expressed. These findings reveal new aspects of Xenorhabdus bacteria interactions with and transmission by their Steinernema nematode hosts, and demonstrate that bacterial SR1 genes aid in colonizing nematode epithelial surfaces. PMID:23480552

Pre-treatment with Bifidobacterium breve UCC2003 modulates Citrobacter rodentium-induced colonic inflammation and organ specificity.

PubMed

Collins, James W; Akin, Ali R; Kosta, Artemis; Zhang, Ning; Tangney, Mark; Francis, Kevin P; Frankel, Gad

2012-11-01

Citrobacter rodentium, which colonizes the gut mucosa via formation of attaching and effacing (A/E) lesions, causes transmissible colonic hyperplasia. The aim of this study was to evaluate whether prophylactic treatment with Bifidobacterium breve UCC2003 can improve the outcome of C. rodentium infection. Six-week-old albino C57BL/6 mice were pre-treated for 3 days with B. breve, challenged with bioluminescent C. rodentium and administered B. breve or PBS-C for 8 days post-infection; control mice were either administered B. breve and mock-infected with PBS, or mock-treated with PBS-C and mock-infected with PBS. C. rodentium colonization was monitored by bacterial enumeration from faeces and by a combination of both 2D bioluminescence imaging (BLI) and composite 3D diffuse light imaging tomography with µCT imaging (DLIT-µCT). At day 8 post-infection, colons were removed and assessed for crypt hyperplasia, histology by light microscopy, bacterial colonization by immunofluorescence, and A/E lesion formation by electron microscopy. Prophylactic administration of B. breve did not prevent C. rodentium colonization or A/E lesion formation. However, this treatment did alter C. rodentium distribution within the large intestine and significantly reduced colonic crypt hyperplasia at the peak of bacterial infection. These results show that B. breve could not competitively exclude C. rodentium, but reduced pathogen-induced colonic inflammation.

Investigating Bacterial-Animal Symbioses with Light Sheet Microscopy

PubMed Central

Taormina, Michael J.; Jemielita, Matthew; Stephens, W. Zac; Burns, Adam R.; Troll, Joshua V.; Parthasarathy, Raghuveer; Guillemin, Karen

2014-01-01

SUMMARY Microbial colonization of the digestive tract is a crucial event in vertebrate development, required for maturation of host immunity and establishment of normal digestive physiology. Advances in genomic, proteomic, and metabolomic technologies are providing a more detailed picture of the constituents of the intestinal habitat, but these approaches lack the spatial and temporal resolution needed to characterize the assembly and dynamics of microbial communities in this complex environment. We report the use of light sheet microscopy to provide high resolution imaging of bacterial colonization of the zebrafish intestine. The methodology allows us to characterize bacterial population dynamics across the entire organ and the behaviors of individual bacterial and host cells throughout the colonization process. The large four-dimensional datasets generated by these imaging approaches require new strategies for image analysis. When integrated with other “omics” datasets, information about the spatial and temporal dynamics of microbial cells within the vertebrate intestine will provide new mechanistic insights into how microbial communities assemble and function within hosts. PMID:22983029

Colon and rectal injuries.

PubMed

Cleary, Robert K; Pomerantz, Richard A; Lampman, Richard M

2006-08-01

This study was designed to develop treatment algorithms for colon, rectal, and anal injuries based on the review of relevant literature. Information was obtained through a MEDLINE ( www.nobi.nih.gov/entrez/query.fcgi ) search, and additional references were obtained through cross-referencing key articles cited in these papers. A total of 203 articles were considered relevant. The management of penetrating and blunt colon, rectal, and anal injuries has evolved during the past 150 years. Since the World War II mandate to divert penetrating colon injuries, primary repair or resection and anastomosis have found an increasing role in patients with nondestructive injuries. A critical review of recent literature better defines the role of primary repair and fecal diversion for these injuries and allows for better algorithms for the management of these injuries.

Impact of Experimental Human Pneumococcal Carriage on Nasopharyngeal Bacterial Densities in Healthy Adults

PubMed Central

Shak, Joshua R.; Cremers, Amelieke J. H.; Gritzfeld, Jenna F.; de Jonge, Marien I.; Hermans, Peter W. M.; Vidal, Jorge E.; Klugman, Keith P.; Gordon, Stephen B.

2014-01-01

Colonization of the nasopharynx by Streptococcus pneumoniae is a necessary precursor to pneumococcal diseases that result in morbidity and mortality worldwide. The nasopharynx is also host to other bacterial species, including the common pathogens Staphylococcus aureus, Haemophilus influenzae, and Moraxella catarrhalis. To better understand how these bacteria change in relation to pneumococcal colonization, we used species-specific quantitative PCR to examine bacterial densities in 52 subjects 7 days before, and 2, 7, and 14 days after controlled inoculation of healthy human adults with S. pneumoniae serotype 6B. Overall, 33 (63%) of subjects carried S. pneumoniae post-inoculation. The baseline presence and density of S. aureus, H. influenzae, and M. catarrhalis were not statistically associated with likelihood of successful pneumococcal colonization at this study’s sample size, although a lower rate of pneumococcal colonization in the presence of S. aureus (7/14) was seen compared to that in the presence of H. influenzae (12/16). Among subjects colonized with pneumococci, the number also carrying either H. influenzae or S. aureus fell during the study and at 14 days post-inoculation, the proportion carrying S. aureus was significantly lower among those who were colonized with S. pneumoniae (p = 0.008) compared to non-colonized subjects. These data on bacterial associations are the first to be reported surrounding experimental human pneumococcal colonization and show that co-colonizing effects are likely subtle rather than absolute. PMID:24915552

Fungal Colonization and Biodeterioration of Plasticized Polyvinyl Chloride

PubMed Central

Webb, Jeremy S.; Nixon, Marianne; Eastwood, Ian M.; Greenhalgh, Malcolm; Robson, Geoffrey D.; Handley, Pauline S.

2000-01-01

Significant substratum damage can occur when plasticized PVC (pPVC) is colonized by microorganisms. We investigated microbial colonization of pPVC in an in situ, longitudinal study. Pieces of pPVC containing the plasticizers dioctyl phthalate and dioctyl adipate (DOA) were exposed to the atmosphere for up to 2 years. Fungal and bacterial populations were quantified, and colonizing fungi were identified by rRNA gene sequencing and morphological characteristics. Aureobasidium pullulans was the principal colonizing fungus, establishing itself on the pPVC between 25 and 40 weeks of exposure. A group of yeasts and yeast-like fungi, including Rhodotorula aurantiaca and Kluyveromyces spp., established themselves on the pPVC much later (after 80 weeks of exposure). Numerically, these organisms dominated A. pullulans after 95 weeks, with a mean viable count ± standard error of 1,000 ± 200 yeast CFU cm−2, compared to 390 ± 50 A. pullulans CFU cm−2. No bacterial colonization was observed. We also used in vitro tests to characterize the deteriogenic properties of fungi isolated from the pPVC. All strains of A. pullulans tested could grow with the intact pPVC formulation as the sole source of carbon, degrade the plasticizer DOA, produce extracellular esterase, and cause weight loss of the substratum during growth in vitro. In contrast, several yeast isolates could not grow on pPVC or degrade DOA. These results suggest that microbial succession may occur during the colonization of pPVC and that A. pullulans is critical to the establishment of a microbial community on pPVC. PMID:10919769

The post-trial effect of oral periodic presumptive treatment for vaginal infections on the incidence of bacterial vaginosis and Lactobacillus colonization

PubMed Central

Balkus, Jennifer E.; Jaoko, Walter; Mandaliya, Kishorchandra; Richardson, Barbra A.; Masese, Linnet; Gitau, Ruth; Kiarie, James; Marrazzo, Jeanne; Farquhar, Carey; McClelland, R. Scott

2012-01-01

Background We previously demonstrated a decrease in bacterial vaginosis (BV) and an increase in Lactobacillus colonization among randomized controlled trial (RCT) participants who received monthly oral periodic presumptive treatment (PPT) [2g metronidazole + 150mg fluconazole]. Post-trial data were analyzed to test the hypothesis that the treatment effect would persist following completion of one year of PPT. Methods Data were obtained from women who completed all 12 RCT visits and attended ≥1 post-trial visit within 120 days following completion of the RCT. We used Andersen-Gill proportional hazards models to estimate the post-trial effect of the intervention on the incidence of BV by Gram stain and detection of Lactobacillus species by culture. Results The analysis included 165 subjects (83 active and 82 placebo). The post-trial incidence of BV was 260 per 100 person-years in the intervention arm versus 358 per 100 person-years in the placebo arm (hazard ratio [HR]=0.76; 95% confidence interval [CI]: 0.51–1.12). The post-trial incidence of Lactobacillus colonization was 180 per 100 person-years in the intervention arm versus 127 per 100 person-years in the placebo arm (HR=1.42; 95% CI: 0.85–2.71). Conclusions Despite a decrease in BV and an increase in Lactobacillus colonization during the RCT, the effect of PPT was not sustained at the same level following cessation of the intervention. New interventions that reduce BV recurrence and promote Lactobacillus colonization without the need for ongoing treatment are needed. PMID:22504600

Primary bacterial peritonitis in dogs and cats: 24 cases (1990-2006).

PubMed

Culp, William T N; Zeldis, Tracy E; Reese, Michael S; Drobatz, Kenneth J

2009-04-01

To determine clinical characteristics of primary bacterial peritonitis (infection of the peritoneal cavity with no identifiable intraperitoneal source of infection) and compare characteristics of primary and secondary peritonitis in dogs and cats. Retrospective case series. 24 (primary peritonitis) and 60 (secondary peritonitis) client-owned dogs and cats. Data from medical records of dogs and cats with primary and secondary peritonitis were reviewed for descriptive information regarding primary peritonitis and for comparison between the 2 forms of peritonitis. 15 dogs and 9 cats met inclusion criteria for primary peritonitis, and 49 dogs and 11 cats met inclusion criteria for secondary peritonitis. The most common historical findings in dogs and cats with primary and secondary peritonitis were lethargy, vomiting, and anorexia. Dogs with secondary peritonitis more often developed peritoneal exudates than those with primary peritonitis, and dogs with primary peritonitis were more often infected with gram-positive bacteria than those with secondary peritonitis. No difference in outcome was detected between all animals with primary versus secondary peritonitis; however, dogs with secondary peritonitis treated with surgery were more commonly discharged than those with primary peritonitis treated with surgery. Differences in primary and secondary peritonitis related to historical, physical examination, and clinical laboratory findings; bacteriologic findings; peritoneal effusion characteristics; and outcome were detected. However, larger case numbers are needed before alternative recommendations, such as avoidance of surgery, can be made.

Maternal influences on fetal microbial colonization and immune development

PubMed Central

Romano-Keeler, Joann; Weitkamp, Jörn-Hendrik

2014-01-01

While critical for normal development, the exact timing of establishment of the intestinal microbiome is unknown. For example, although preterm labor and birth have been associated with bacterial colonization of the amniotic cavity and fetal membranes for many years, the prevailing dogma of a sterile intrauterine environment during normal term pregnancies has been challenged more recently. While found to be a key contributor of evolution in the animal kingdom, maternal transmission of commensal bacteria may also constitute a critical process during healthy pregnancies in humans with yet unclear developmental importance. Metagenomic sequencing has elucidated a rich placental microbiome in normal term pregnancies likely providing important metabolic and immune contributions to the growing fetus. Conversely, an altered microbial composition during pregnancy may produce aberrant metabolites impairing fetal brain development and life-long neurological outcomes. Here we review the current understanding of microbial colonization at the feto-maternal interface and explain how normal gut colonization drives a balanced neonatal mucosal immune system, while dysbiosis contributes to aberrant immune function early in life and beyond. We discuss how maternal genetics, diet, medications, and probiotics inform the fetal microbiome in preparation for perinatal and postnatal bacterial colonization. PMID:25310759

Colonization of chicken cecae by Escherichia coli associated with hemorrhagic colitis.

PubMed Central

Beery, J T; Doyle, M P; Schoeni, J L

1985-01-01

Bacterial enumeration, histologic examination, and immunoperoxidase staining demonstrated the ability of an Escherichia coli strain associated with hemorrhagic colitis (serotype O157:H7) to colonize chicken cecae for up to 90 days postinoculation after a peroral challenge at 1 day of age. The bacteria induced mild, transient, mucous membrane damage confined to the proximal cecae of healthy, normal-appearing chickens, principally at 14 to 28 days postinoculation. Attachment, effacement, and penetration of the cecal surface epithelium by E. coli O157:H7 were observed. With the exception of splenic, hepatic, and cecal tonsil immune-related changes and cecal damage and colonization, no other organ systems or portions of the gastrointestinal tract were affected by the bacteria. Bacterial counts indicated that E. coli O157:H7 was predominantly present in the cecae (often at levels greater than 10(6) CFU/g of tissue and contents) and to a lesser extent in the colon. Our results suggest that E. coli O157:H7 colonizes chicken cecae and is passed through the colon with fecal excrement. The ability of this organism to colonize chicken cecae indicates that chickens may serve as hosts and possibly as reservoirs for E. coli O157:H7. Images PMID:3885853

Anti-bacterial antibody and T cell responses in bronchiectasis are differentially associated with lung colonization and disease.

PubMed

Jaat, Fathia G; Hasan, Sajidah F; Perry, Audrey; Cookson, Sharon; Murali, Santosh; Perry, John D; Lanyon, Clare V; De Soyza, Anthony; Todryk, Stephen M

2018-05-30

As a way to determine markers of infection or disease informing disease management, and to reveal disease-associated immune mechanisms, this study sought to measure antibody and T cell responses against key lung pathogens and to relate these to patients' microbial colonization status, exacerbation history and lung function, in Bronchiectasis (BR) and Chronic Obstructive Pulmonary Disease (COPD). One hundred nineteen patients with stable BR, 58 with COPD and 28 healthy volunteers were recruited and spirometry was performed. Bacterial lysates were used to measure specific antibody responses by ELISA and T cells by ELIspot. Cytokine secretion by lysate-stimulated T cells was measured by multiplex cytokine assay whilst activation phenotype was measured by flow cytometry. Typical colonization profiles were observed in BR and COPD, dominated by P.aeruginosa, H.influenzae, S.pneumoniae and M.catarrhalis. Colonization frequency was greater in BR, showing association with increased antibody responses against P.aeruginosa compared to COPD and HV, and with sensitivity of 73% and specificity of 95%. Interferon-gamma T cell responses against P.aeruginosa and S.pneumoniae were reduced in BR and COPD, whilst reactive T cells in BR had similar markers of homing and senescence compared to healthy volunteers. Exacerbation frequency in BR was associated with increased antibodies against P. aeruginosa, M.catarrhalis and S.maltophilia. T cell responses against H.influenzae showed positive correlation with FEV 1 % (r = 0.201, p = 0.033) and negative correlation with Bronchiectasis Severity Index (r = - 0.287, p = 0.0035). Our findings suggest a difference in antibody and T cell immunity in BR, with antibody being a marker of exposure and disease in BR for P.aeruginosa, M.catarrhalis and H.influenzae, and T cells a marker of reduced disease for H.influenzae.

Osteopontin mediates Citrobacter rodentium-induced colonic epithelial cell hyperplasia and attaching-effacing lesions.

PubMed

Wine, Eytan; Shen-Tu, Grace; Gareau, Mélanie G; Goldberg, Harvey A; Licht, Christoph; Ngan, Bo-Yee; Sorensen, Esben S; Greenaway, James; Sodek, Jaro; Zohar, Ron; Sherman, Philip M

2010-09-01

Although osteopontin (OPN) is up-regulated in inflammatory bowel diseases, its role in disease pathogenesis remains controversial. The objective of this study was to determine the role of OPN in host responses to a non-invasive bacterial pathogen, Citrobacter rodentium, which serves as a murine infectious model of colitis. OPN gene knockout and wild-type mice were infected orogastrically with either C. rodentium or Luria-Bertani (LB) broth. Mouse-derived OPN(+/+) and OPN(-/-) fibroblasts were incubated with C. rodentium and attaching-effacing lesions were demonstrated using transmission electron microscopy and immunofluorescence. Colonic expression of OPN was increased by C. rodentium infection of wild-type mice. Furthermore, colonic epithelial cell hyperplasia, the hallmark of C. rodentium infection, was reduced in OPN(-/-) mice, and spleen enlargement by infection was absent in OPN(-/-) mice. Rectal administration of OPN to OPN(-/-) mice restored these effects. There was an 8- to 17-fold reduction in bacterial colonization in OPN(-/-) mice, compared with wild-type mice, which was accompanied by reduced attaching-effacing lesions, both in infected OPN(-/-) mice and OPN(-/-) mouse fibroblasts. Moreover, adhesion pedestals were restored in OPN(-/-) cells complemented with human OPN. Therefore, lack of OPN results in decreased pedestal formation, colonization, and colonic epithelial cell hyperplasia responses to C. rodentium infection, indicating that OPN impacts disease pathogenesis through bacterial attachment and altered host immune responses.

[Penetrant injuries of colon--our experience].

PubMed

Lazović, R; Krivokapić, Z; Dobricanin, V

2010-01-01

In attemption to determine the place of primary repair in management of colon injuries, an open, non randomized clinical study was performed. Retrospective (RS) group of 62 patients according to exclusion criteria by Stone (S/F) and Flint (F1) was managed by one or two stage surgical procedure. Prospective (PR) group of 34 patients was managed using one stage repair non-selectively: two stage procedures were performed in 3 cases of advanced peritonitis and multi-segmental lacerations with impaired circulation of colon. In RS group 36 patients were managed by primary repair and in PR group, 31 were managed by primary repair. Both groups were of similar age/sex. Indexes of trauma severity were similar (TS, ISS, PATI). The latent time was shorter in PR group. Associated injuries to other body regions and abdominal organs were similar in both groups. S/F criteria and Flint grading in both (RS vs. PR) groups were similar. Comparison of attempted and successful primary repairs justifies the more liberal use of primary repair in early management of colon injuries.

Medical-grade honey does not reduce skin colonization at central venous catheter-insertion sites of critically ill patients: a randomized controlled trial

PubMed Central

2012-01-01

Introduction Catheter-related bloodstream infections (CRBSIs) associated with short-term central venous catheters (CVCs) in intensive care unit (ICU) patients are a major clinical problem. Bacterial colonization of the skin at the CVC insertion site is an important etiologic factor for CRBSI. The aim of this study was to assess the efficacy of medical-grade honey in reducing bacterial skin colonization at insertion sites. Methods A prospective, single-center, open-label randomized controlled trial was performed at the ICU of a university hospital in The Netherlands to assess the efficacy of medical-grade honey to reduce skin colonization of insertion sites. Medical-grade honey was applied in addition to standard CVC-site dressing and disinfection with 0.5% chlorhexidine in 70% alcohol. Skin colonization was assessed on a daily basis before CVC-site disinfection. The primary end point was colonization of insertion sites with >100 colony-forming units at the last sampling before removal of the CVC or transfer of the patient from the ICU. Secondary end points were quantitative levels of colonization of the insertion sites and colonization of insertion sites stratified for CVC location. Results Colonization of insertion sites was not affected by the use of medical-grade honey, as 44 (34%) of 129 and 36 (34%) of 106 patients in the honey and standard care groups, respectively, had a positive skin culture (P = 0.98). Median levels of skin colonization at the last sampling were 1 (0 to 2.84) and 1 (0 to 2.70) log colony-forming units (CFUs)/swab for the honey and control groups, respectively (P = 0.94). Gender, days of CVC placement, CVC location, and CVC type were predictive for a positive skin culture. Correction for these variables did not change the effect of honey on skin-culture positivity. Conclusions Medical-grade honey does not affect colonization of the skin at CVC insertion sites in ICU patients when applied in addition to standard disinfection with 0

Medical-grade honey does not reduce skin colonization at central venous catheter-insertion sites of critically ill patients: a randomized controlled trial.

PubMed

Kwakman, Paulus H; Müller, Marcella C; Binnekade, Jan M; van den Akker, Johannes P; de Borgie, Corianne A; Schultz, Marcus J; Zaat, Sebastian A

2012-10-30

Catheter-related bloodstream infections (CRBSIs) associated with short-term central venous catheters (CVCs) in intensive care unit (ICU) patients are a major clinical problem. Bacterial colonization of the skin at the CVC insertion site is an important etiologic factor for CRBSI. The aim of this study was to assess the efficacy of medical-grade honey in reducing bacterial skin colonization at insertion sites. A prospective, single-center, open-label randomized controlled trial was performed at the ICU of a university hospital in The Netherlands to assess the efficacy of medical-grade honey to reduce skin colonization of insertion sites. Medical-grade honey was applied in addition to standard CVC-site dressing and disinfection with 0.5% chlorhexidine in 70% alcohol. Skin colonization was assessed on a daily basis before CVC-site disinfection. The primary end point was colonization of insertion sites with >100 colony-forming units at the last sampling before removal of the CVC or transfer of the patient from the ICU. Secondary end points were quantitative levels of colonization of the insertion sites and colonization of insertion sites stratified for CVC location. Colonization of insertion sites was not affected by the use of medical-grade honey, as 44 (34%) of 129 and 36 (34%) of 106 patients in the honey and standard care groups, respectively, had a positive skin culture (P = 0.98). Median levels of skin colonization at the last sampling were 1 (0 to 2.84) and 1 (0 to 2.70) log colony-forming units (CFUs)/swab for the honey and control groups, respectively (P = 0.94). Gender, days of CVC placement, CVC location, and CVC type were predictive for a positive skin culture. Correction for these variables did not change the effect of honey on skin-culture positivity. Medical-grade honey does not affect colonization of the skin at CVC insertion sites in ICU patients when applied in addition to standard disinfection with 0.5% chlorhexidine in 70% alcohol. Netherlands Trial

Leaf-FISH: Microscale Imaging of Bacterial Taxa on Phyllosphere

PubMed Central

Peredo, Elena L.; Simmons, Sheri L.

2018-01-01

Molecular methods for microbial community characterization have uncovered environmental and plant-associated factors shaping phyllosphere communities. Variables undetectable using bulk methods can play an important role in shaping plant-microbe interactions. Microscale analysis of bacterial dynamics in the phyllosphere requires imaging techniques specially adapted to the high autoflouresence and 3-D structure of the leaf surface. We present an easily-transferable method (Leaf-FISH) to generate high-resolution tridimensional images of leaf surfaces that allows simultaneous visualization of multiple bacterial taxa in a structurally informed context, using taxon-specific fluorescently labeled oligonucleotide probes. Using a combination of leaf pretreatments coupled with spectral imaging confocal microscopy, we demonstrate the successful imaging bacterial taxa at the genus level on cuticular and subcuticular leaf areas. Our results confirm that different bacterial species, including closely related isolates, colonize distinct microhabitats in the leaf. We demonstrate that highly related Methylobacterium species have distinct colonization patterns that could not be predicted by shared physiological traits, such as carbon source requirements or phytohormone production. High-resolution characterization of microbial colonization patterns is critical for an accurate understanding of microbe-microbe and microbe-plant interactions, and for the development of foliar bacteria as plant-protective agents. PMID:29375531

Combination of therapeutic ultrasound with antibiotics interfere with the growth of bacterial culture that colonizes skin ulcers: An in-vitro study.

PubMed

Guirro, Elaine Caldeira de Oliveira; Angelis, Dejanira de Franceschi de; Sousa, Natanael Teixeira Alves de; Guirro, Rinaldo Roberto de Jesus

2016-09-01

Staphylococcus aureus and Escherichia coli are among the major bacterial species that colonize skin ulcers. Therapeutic ultrasound (TUS) produces biophysical effects that are relevant to wound healing; however, its application over a contaminated injury is not evidence-based. The objective of this research was to analyze the effect of TUS on in vitro-isolated S. aureus and E. coli, including the combination of ultrasound and antibiotics, in order to assess their antibiotic action on bacterial susceptibility. For the experiments, the bacterial strains were suspended in saline, then diluted (10(4)CFU/mL) for irradiation (at 1 and 3MHz, 0.5 and 0.8W/cm(2) for 0 and 15min) and the combination treatment of ultrasonication and antibiotics was administered by adding nalidixic acid (S. aureus) and tetracycline (E. coli) at concentrations equivalent to 50% of the minimum inhibitory concentration (MIC). The experiments were carried out in duplicate with six repetitions. The suspensions were inoculated on to Petri plates and incubated at 37°C and the colony forming units (CFUs) were counted after 24h. The results were subjected to the Shapiro-Wilk normality test, followed by parametric ANOVA and Tukey's post hoc test at a significance level of 1%. The results demonstrated that the action of TUS at 1MHz inhibited bacterial growth while at 3MHz, bacterial growth was observed in both species. However, the synergistic combination of ultrasound and antibiotics was able to inhibit the growth of both bacteria completely after 15min of ultrasonication. The results suggest that the action of ultrasound on S. aureus and E. coli are dependent on the oscillation frequency as well as the intensity and time of application. The combination of ultrasound with antibiotics was able to inhibit bacterial growth fully at all frequencies and doses in both species. Copyright © 2016 Elsevier B.V. All rights reserved.

Oral and endotracheal tubes colonization by periodontal bacteria: a case-control ICU study.

PubMed

Porto, A N; Cortelli, S C; Borges, A H; Matos, F Z; Aquino, D R; Miranda, T B; Oliveira Costa, F; Aranha, A F; Cortelli, J R

2016-03-01

Periodontal infection is a possible risk factor for respiratory disorders; however, no studies have assessed the colonization of periodontal pathogens in endotracheal tubes (ET). This case-control study analyzed whether periodontal pathogens are able to colonize ET of dentate and edentulous patients in intensive care units (ICU) and whether oral and ET periodontal pathogen profiles have any correlation between these patients. We selected 18 dentate and 18 edentulous patients from 78 eligible ICU patients. Oral clinical examination including probing depth, clinical attachment level, gingival index , and plaque index was performed by a single examiner, followed by oral and ET sampling and processing by quantitative polymerase chain reaction (total bacterial load, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia). Data were statistically analyzed by Mann-Whitney U, two-way analysis of variance (p < 0.05). Among dentate, there was no correlation between clinical parameters and ET bacterial levels. Both dentate and edentulous patients showed similar ET bacterial levels. Dentate patients showed no correlation between oral and ET bacterial levels, while edentulous patients showed positive correlations between oral and ET levels of A. actinomycetemcomitans, P. gingivalis, and T. forsythia. Periodontal pathogens can colonize ET and the oral cavity of ICU patients. Periodontal pathogen profiles tend to be similar between dentate and edentulous ICU patients. In ICU patients, oral cavity represents a source of ET contamination. Although accompanied by higher oral bacterial levels, teeth do not seem to influence ET bacterial profiles.

Effects of Glucosinolates and Flavonoids on Colonization of the Roots of Brassica napus by Azorhizobium caulinodans ORS571

PubMed Central

O'Callaghan, Kenneth J.; Stone, Philip J.; Hu, Xiaojia; Griffiths, D. Wynne; Davey, Michael R.; Cocking, Edward C.

2000-01-01

Plants of Brassica napus were assessed quantitatively for their susceptibility to lateral root crack colonization by Azorhizobium caulinodans ORS571(pXLGD4) (a rhizobial strain carrying the lacZ reporter gene) and for the concentration of glucosinolates in their roots by high-pressure liquid chromatography (HPLC). High- and low-glucosinolate-seed (HGS and LGS) varieties exhibited a relatively low and high percentage of colonized lateral roots, respectively. HPLC showed that roots of HGS plants contained a higher concentration of glucosinolates than roots of LGS plants. One LGS variety showing fewer colonized lateral roots than other LGS varieties contained a higher concentration of glucosinolates than other LGS plants. Inoculated HGS plants treated with the flavonoid naringenin showed significantly more colonization than untreated HGS plants. This increase was not mediated by a naringenin-induced lowering of the glucosinolate content of HGS plant roots, nor did naringenin induce bacterial resistance to glucosinolates or increase the growth of bacteria. The erucic acid content of seed did not appear to influence colonization by azorhizobia. Frequently, leaf assays are used to study glucosinolates and plant defense; this study provides data on glucosinolates and bacterial colonization in roots and describes a bacterial reporter gene assay tailored easily to the study of ecologically important phytochemicals that influence bacterial colonization. These data also form a basis for future assessments of the benefits to oilseed rape plants of interaction with plant growth-promoting bacteria, especially diazotrophic bacteria potentially able to extend the benefits of nitrogen fixation to nonlegumes. PMID:10788398

Bisphosphonates enhance bacterial adhesion and biofilm formation on bone hydroxyapatite.

PubMed

Kos, Marcin; Junka, Adam; Smutnicka, Danuta; Szymczyk, Patrycja; Gluza, Karolina; Bartoszewicz, Marzenna

2015-07-01

Because of the suspicion that bisphosphonates enhance bacterial colonization, this study evaluated adhesion and biofilm formation by Streptococcus mutans 25175, Staphylococcus aureus 6538, and Pseudomonas aeruginosa 14454 reference strains on hydroxyapatite coated with clodronate, pamidronate, or zoledronate. Bacterial strains were cultured on bisphosphonate-coated and noncoated hydroxyapatite discs. After incubation, nonadhered bacteria were removed by centrifugation. Biofilm formation was confirmed by scanning electron microscopy. Bacterial colonization was estimated using quantitative cultures compared by means with Kruskal-Wallis and post-hoc Student-Newman-Keuls tests. Modeling of the interactions between bisphosphonates and hydroxyapatite was performed using the Density Functional Theory method. Bacterial colonization of the hydroxyapatite discs was significantly higher for all tested strains in the presence of bisphosphonates vs. Adherence in the presence of pamidronate was higher than with other bisphosphonates. Density Functional Theory analysis showed that the protonated amine group of pamidronate, which are not present in clodronate or zoledronate, forms two additional hydrogen bonds with hydroxyapatite. Moreover, the reactive cationic amino group of pamidronate may attract bacteria by direct electrostatic interaction. Increased bacterial adhesion and biofilm formation can promote osteomyelitis, cause failure of dental implants or bisphosphonate-coated joint prostheses, and complicate bone surgery in patients on bisphosphonates. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Colon Trauma: Evidence-Based Practices.

PubMed

Yamamoto, Ryo; Logue, Alicia J; Muir, Mark T

2018-01-01

Colon injury is not uncommon and occurs in about a half of patients with penetrating hollow viscus injuries. Despite major advances in the operative management of penetrating colon wounds, there remains discussion regarding the appropriate treatment of destructive colon injuries, with a significant amount of scientific evidence supporting segmental resection with primary anastomosis in most patients without comorbidities or large transfusion requirement. Although literature is sparse concerning the management of blunt colon injuries, some studies have shown operative decision based on an algorithm originally defined for penetrating wounds should be considered in blunt colon injuries. The optimal management of colonic injuries in patients requiring damage control surgery (DCS) also remains controversial. Studies have recently reported that there is no increased risk compared with patients treated without DCS if fascial closure is completed on the first reoperation, or that a management algorithm for penetrating colon wounds is probably efficacious for colon injuries in the setting of DCS as well.

Resection and primary anastomosis without diverting ileostomy for left colon emergencies: is it a safe procedure?

PubMed

Jiménez Fuertes, Montiel; Costa Navarro, David

2012-05-01

Large-bowel obstruction and perforation are still frequently occurring entities for the acute care surgeon. In these cases, Hartmann's procedure is the most commonly used surgical technique. However, recent papers demonstrate that colon resection and primary anastomosis (RPA) in the emergency setting is a safe and feasible procedure. We present our series of left colon resection and primary anastomosis procedures from Torrevieja Hospital (Alicante, Spain), performed without bowel irrigation or a diverting ileostomy. Thirty-two RPA procedures were performed in emergency settings for perforation or obstruction, or both, during an 18-month period. The following data were prospectively collected: age, gender, nationality, diagnoses, ASA score, body mass index (BMI), POSSUM score (Physiological and Operative Severity Score for the enumeration of Mortality and morbidity), and the score according to the Hinchey classification. Furthermore, duration of the operation, length of postoperative hospital stay, and mortality and morbidity data were recorded. Sixteen of these patients were diagnosed with acute diverticulitis, 14 patients with neoplasm (of which 9 cases had obstruction, 2 cases had perforation, and 3 cases had both), and foreign body perforation in the remaining 2 cases. The mean hospital stay was 7.8 (range, 4-10) days. The physiological POSSUM score was 24.4 (range, 15-39), and the surgical POSSUM score was 19.8 (range, 16-24). None of the patients died (0% mortality). Seven patients developed some kind of complication (21.9%), all of which were managed conservatively. The results of this study suggest that RPA for left colon obstruction and perforation in emergency settings can be safely performed in certain surgical conditions.

The Intersection Between Colonization Resistance, Antimicrobial Stewardship, and Clostridium difficile.

PubMed

Rosa, Rossana; Donskey, Curtis J; Munoz-Price, L Silvia

2018-06-07

Colonization resistance refers to the innate defense provided by the indigenous microbiota against colonization by pathogenic organisms. We aim to describe how this line of defense is deployed against Clostridium difficile and what the implications are for interventions directed by Antimicrobial Stewardship Programs. The indigenous microbiota provides colonization resistance through depletion of nutrients, prevention of access to adherence sites within the gut mucosa, production of inhibitory substances, and stimulation of the host's immune system. The ability to quantify colonization resistance could provide information regarding periods of maximal vulnerability to colonization with pathogens and also allow the identification of mechanisms of restoration of colonization resistance. Methods utilized to determine the composition of the gut microbiota include sequencing technologies and measurement of concentration of specific bacterial metabolites. Use of innovations in the quantification of colonization resistance can expand the role of Antimicrobial Stewardship from prevention of disruption of the indigenous microbiota to restoration of colonization resistance.

An Ribonuclease T2 Family Protein Modulates Acinetobacter baumannii Abiotic Surface Colonization

PubMed Central

Jacobs, Anna C.; Blanchard, Catlyn E.; Catherman, Seana C.; Dunman, Paul M.; Murata, Yoshihiko

2014-01-01

Acinetobacter baumannii is an emerging bacterial pathogen of considerable medical concern. The organism's transmission and ability to cause disease has been associated with its propensity to colonize and form biofilms on abiotic surfaces in health care settings. To better understand the genetic determinants that affect biomaterial attachment, we performed a transposon mutagenesis analysis of abiotic surface-colonization using A. baumannii strain 98-37-09. Disruption of an RNase T2 family gene was found to limit the organism's ability to colonize polystyrene, polypropylene, glass, and stainless steel surfaces. DNA microarray analyses revealed that in comparison to wild type and complemented cells, the RNase T2 family mutant exhibited reduced expression of 29 genes, 15 of which are predicted to be associated with bacterial attachment and surface-associated motility. Motility assays confirmed that RNase T2 mutant displays a severe motility defect. Taken together, our results indicate that the RNase T2 family protein identified in this study is a positive regulator of A. baumannii's ability to colonize inanimate surfaces and motility. Moreover, the enzyme may be an effective target for the intervention of biomaterial colonization, and consequently limit the organism's transmission within the hospital setting. PMID:24489668

The effect of a changed environment on bacterial colonization rates in an established burns centre

PubMed Central

Wormald, P. J.

1970-01-01

In an established burns centre which moved from an old building to new purpose-designed premises, colonization rates of patients' burns with Staphylococcus aureus, Pseudomonas aeruginosa and other Gram-negative bacilli were not reduced. Colonization rates with Streptococcus pyogenes increased but the increase was mainly due to multiple importations in the new premises of a strain of higher communicability than any seen in the old. In the first 32 months in the new environment 10 patients were found colonized with pseudomonas on admission and 20 became colonized in the unit. A much higher proportion of patients with burns of more than 30% body surface became colonized than of patients with less. About one-third of the above 20 patients became colonized with strains already isolated from another patient; all but one of them had small area burns. Cross-infection was not observed from numerous heavily colonized patients with high percentage burns. This paradox is discussed in detail. Basin outflows in the new premises became colonized with P. aeruginosa of two serotypes not found on patients in this unit. PMID:4993291

The effect of a changed environment on bacterial colonization rates in an established burns centre.

PubMed

Wormald, P J

1970-12-01

In an established burns centre which moved from an old building to new purpose-designed premises, colonization rates of patients' burns with Staphylococcus aureus, Pseudomonas aeruginosa and other Gram-negative bacilli were not reduced. Colonization rates with Streptococcus pyogenes increased but the increase was mainly due to multiple importations in the new premises of a strain of higher communicability than any seen in the old.In the first 32 months in the new environment 10 patients were found colonized with pseudomonas on admission and 20 became colonized in the unit. A much higher proportion of patients with burns of more than 30% body surface became colonized than of patients with less. About one-third of the above 20 patients became colonized with strains already isolated from another patient; all but one of them had small area burns. Cross-infection was not observed from numerous heavily colonized patients with high percentage burns. This paradox is discussed in detail. Basin outflows in the new premises became colonized with P. aeruginosa of two serotypes not found on patients in this unit.

Bifidobacterium longum subspecies infantis: champion colonizer of the infant gut

PubMed Central

Underwood, Mark A.; German, J. Bruce; Lebrilla, Carlito B.; Mills, David A.

2015-01-01

Oligosaccharides are abundant in human milk. Production of these highly diverse structures requires significant energy expenditure by the mother and yet these human milk oligosaccharides offer no direct nutritive value to her infant. A primary function of human milk oligosaccharides is to shape the infant’s intestinal microbiota with life-long consequences. Bifidobacterium longum subspecies infantis (B. infantis) is unique among gut bacteria in its prodigious capacity to digest and consume any human milk oligosaccharide structure, the result of a large repertoire of bacterial genes encoding an array of glycosidases and oligosaccharide transporters not found in other bacterial species. In vitro, B. infantis grows better than other bacterial strains in the presence of human milk oligosaccharides, displays anti-inflammatory activity in premature intestinal cells, and decreases intestinal permeability. In premature infants, B. infantis given in combination with human milk increases B. infantis and decreases Enterobacteriaceae in the feces. Probiotics containing B. infantis decrease the risk of necrotizing enterocolitis in premature infants. Colonization with B. infantis is also associated with increased vaccine responses. Probiotic organisms have historically been selected based on ease of production and stability. The advantages of B. infantis, selected through coevolution with human milk glycans, present an opportunity for focused manipulation of the infant intestinal microbiota. PMID:25303277

Polysaccharide from seeds of Plantago asiatica L. affects lipid metabolism and colon microbiota of mouse.

PubMed

Hu, Jie-Lun; Nie, Shao-Ping; Wu, Qi-Meng; Li, Chang; Fu, Zhi-Hong; Gong, Joshua; Cui, Steve W; Xie, Ming-Yong

2014-01-08

Polysaccharide from the seeds of Plantago asiatica L. was given via oral administration to mice (0.4 g/kg body weight, 30 days) to observe its effects on mouse nutrient metabolism and colon microbiota. It was found the polysaccharide intake could lower the apparent absorption of lipid. Total triglyceride, cholesterol, and atherogenic index in blood serum with total lipid and cholesterol levels in liver of polysaccharide group mice were all significantly lower than those of the control group (p < 0.05). Furthermore, the effect of the polysaccharide intake on mouse colon bacterial communities was investigated. Mice from the polysaccharide group showed a higher colon bacterial diversity than the control group. Bacteroides sp., Eubacterium sp., butyrate-producing bacteria Butyrivibrio sp., and probiotics Bifidobacterium bifidum , Lactobacillus fermentum , and Lactobacillus reuteri in mouse colon were all increased after polysaccharide intake. These indicated that the intake of polysaccharide from P. asiatica L. could be beneficial for lipid metabolism and colon microbiota.

Osteopontin Mediates Citrobacter rodentium-Induced Colonic Epithelial Cell Hyperplasia and Attaching-Effacing Lesions

PubMed Central

Wine, Eytan; Shen-Tu, Grace; Gareau, Mélanie G.; Goldberg, Harvey A.; Licht, Christoph; Ngan, Bo-Yee; Sorensen, Esben S.; Greenaway, James; Sodek, Jaro; Zohar, Ron; Sherman, Philip M.

2010-01-01

Although osteopontin (OPN) is up-regulated in inflammatory bowel diseases, its role in disease pathogenesis remains controversial. The objective of this study was to determine the role of OPN in host responses to a non-invasive bacterial pathogen, Citrobacter rodentium, which serves as a murine infectious model of colitis. OPN gene knockout and wild-type mice were infected orogastrically with either C. rodentium or Luria-Bertani (LB) broth. Mouse-derived OPN+/+ and OPN−/− fibroblasts were incubated with C. rodentium and attaching-effacing lesions were demonstrated using transmission electron microscopy and immunofluorescence. Colonic expression of OPN was increased by C. rodentium infection of wild-type mice. Furthermore, colonic epithelial cell hyperplasia, the hallmark of C. rodentium infection, was reduced in OPN−/− mice, and spleen enlargement by infection was absent in OPN−/− mice. Rectal administration of OPN to OPN−/− mice restored these effects. There was an 8- to 17-fold reduction in bacterial colonization in OPN−/− mice, compared with wild-type mice, which was accompanied by reduced attaching–effacing lesions, both in infected OPN−/− mice and OPN−/− mouse fibroblasts. Moreover, adhesion pedestals were restored in OPN−/− cells complemented with human OPN. Therefore, lack of OPN results in decreased pedestal formation, colonization, and colonic epithelial cell hyperplasia responses to C. rodentium infection, indicating that OPN impacts disease pathogenesis through bacterial attachment and altered host immune responses. PMID:20651246

[Processes of plant colonization by Methylobacterium strains and some bacterial properties ].

PubMed

Romanovskaia, V A; Stoliar, S M; Malashenko, Iu R; Dodatko, T N

2001-01-01

The pink-pigmented facultative methylotrophic bacteria (PPFMB) of the genus Methylobacterium are indespensible inhabitants of the plant phyllosphere. Using maize Zea mays as a model, the ways of plant colonization by PPFMB and some properties of the latter that might be beneficial to plants were studied. A marked strain, Methylobacterium mesophilicum APR-8 (pULB113), was generated to facilitate the detection of the methylotrophic bacteria inoculated into the soil or applied to the maize leaves. Colonization of maize leaves by M. mesophilicum APR-8 (pULB113) occurred only after the bacteria were applied onto the leaf surface. In this case, the number of PPFMB cells on inoculated leaves increased with plant growth. During seed germination, no colonization of maize leaves with M. mesophilicum cells occurred immediately from the soil inoculated with the marked strain. Thus, under natural conditions, colonization of plant leaves with PPFMB seems to occur via soil particle transfer to the leaves by air. PPFMB monocultures were not antagonistic to phytopathogenic bacteria. However, mixed cultures of epiphytic bacteria containing Methylobacterium mesophilicum or M. extorquens did exhibit an antagonistic effect against the phytopathogenic bacteria studied (Xanthomonas camprestris, Pseudomonas syringae, Erwinia carotovora, Clavibacter michiganense, and Agrobacterium tumifaciens). Neither epiphytic and soil strains of Methylobacterium extorquens, M. organophillum, M. mesophilicum, and M. fujisawaense catalyzed ice nucleation. Hence, they cause no frost injury to plants. Thus, the results indicate that the strains of the genus Methylobacterium can protect plants against adverse environmental factors.

Who's on First? Part II: Bacterial and fungal colonization of fresh soil minerals

NASA Astrophysics Data System (ADS)

Whitman, T.; Neurath, R.; Zhang, P.; Yuan, T.; Weber, P. K.; Zhou, J.; Pett-Ridge, J.; Firestone, M. K.

2015-12-01

Soil organic matter (SOM) stabilization by soil minerals is an important mechanism influencing soil C cycling. Microbes make up only a few percent of total SOM, but have a disproportionate impact on SOM cycling. Their direct interactions with soil minerals, however, are not well characterized. We studied colonization of fresh minerals by soil microbes in an Avena barbata (wild oat) California grassland soil microcosm. Examining quartz, ferrihydrite, kaolinite, and the heavy fraction of the native soil, we asked: (1) Do different minerals select for different communities, or do random processes drive the colonization of fresh minerals? (2) What factors influence which taxa colonize fresh minerals? After incubating mesh bags (<18 μm) of minerals buried next to actively growing plant roots for 2 months, we used high-throughput sequencing of 16S and ITS2 genes to characterize the microbial communities colonizing the minerals. We found significant differences between the microbial community composition of different minerals and soil for both bacteria and fungi. We found a higher relative abundance of arbuscular mycorrhial fungi with ferrihydrite and quartz, and nanoscale secondary ion mass spectrometry (NanoSIMS) imaging of these minerals suggests that some fungal hyphae are moving C directly from roots to mineral surfaces. The enriched presence of both nematode-associated fungi (Pochonia sp.) and bacteria (Candidatus Xiphinematobacter) in the minerals suggests that these minerals may be a habitat for nematodes. Bacteria of the family Chitinophagaceae and genus Janthinobacterium were significantly enriched on both ferrihydrite and quartz minerals, both of which may interact with colonizing fungi. These findings suggest that: (1) Microbial colonization of fresh minerals is not a fully passive or neutral process. (2) Mineral exploration by plant-associated fungi and soil fauna transport may be factors in determining the initial colonization of minerals and subsequent C

Ruminococcus bromii is a keystone species for the degradation of resistant starch in the human colon

PubMed Central

Ze, Xiaolei; Duncan, Sylvia H; Louis, Petra; Flint, Harry J

2012-01-01

The release of energy from particulate substrates such as dietary fiber and resistant starch (RS) in the human colon may depend on the presence of specialist primary degraders (or ‘keystone species') within the microbial community. We have explored the roles of four dominant amylolytic bacteria found in the human colon in the degradation and utilization of resistant starches. Eubacterium rectale and Bacteroides thetaiotaomicron showed limited ability to utilize RS2- and RS3-resistant starches by comparison with Bifidobacterium adolescentis and Ruminococcus bromii. In co-culture, however, R. bromii proved unique in stimulating RS2 and RS3 utilization by the other three bacterial species, even in a medium that does not permit growth of R. bromii itself. Having previously demonstrated low RS3 fermentation in vivo in two individuals with undetectable populations of R. bromii-related bacteria, we show here that supplementation of mixed fecal bacteria from one of these volunteers with R. bromii, but not with the other three species, greatly enhanced the extent of RS3 fermentation in vitro. This argues strongly that R. bromii has a pivotal role in fermentation of RS3 in the human large intestine, and that variation in the occurrence of this species and its close relatives may be a primary cause of variable energy recovery from this important component of the diet. This work also indicates that R. bromii possesses an exceptional ability to colonize and degrade starch particles when compared with previously studied amylolytic bacteria from the human colon. PMID:22343308

Transit time affects the community stability of Lactobacillus and Bifidobacterium species in an in vitro model of human colonic microbiotia.

PubMed

Rodes, Laetitia; Paul, Arghya; Coussa-Charley, Michael; Al-Salami, Hani; Tomaro-Duchesneau, Catherine; Fakhoury, Marc; Prakash, Satya

2011-12-01

Retention time, which is analogous to transit time, is an index for bacterial stability in the intestine. Its consideration is of particular importance to optimize the delivery of probiotic bacteria in order to improve treatment efficacy. This study aims to investigate the effect of retention time on Lactobacilli and Bifidobacteria stability using an established in vitro human colon model. Three retention times were used: 72, 96, and 144 h. The effect of retention time on cell viability of different bacterial populations was analyzed with bacterial plate counts and PCR. The proportions of intestinal Bifidobacteria, Lactobacilli, Enterococci, Staphylococci and Clostridia populations, analyzed by plate counts, were found to be the same as that in human colonic microbiota. Retention time in the human colon affected the stability of Lactobacilli and Bifidobacteria communities, with maximum stability observed at 144 h. Therefore, retention time is an important parameter that influences bacterial stability in the colonic microbiota. Future clinical studies on probiotic bacteria formulations should take into consideration gastrointestinal transit parameters to improve treatment efficacy.

[Effect of normal microflora of female reproductive tract in colonization resistance].

PubMed

Cherkasov, S V

2006-01-01

The role of female reproductive tract microflora in the maintenance of biotope colonization resistance was described. The role of lactobacilli possessing antagonistic properties in the reproductive tract defense was assessed. Classification of bacterial mechanisms of colonization resistance including block of the adhesion, antagonistic action of normal microflora associated with the production of antibacterial substances and suppression of allochthonous bacteria persistence characteristics was presented. Colonization resistance was considered as a physiological phenomenon of microecological homeostasis being a result of symbiotic relations of a host organism and autochthonous microflora.

Mutualistic interaction between Salmonella enterica and Aspergillus niger and its effects on Zea mays colonization

PubMed Central

Balbontín, Roberto; Vlamakis, Hera; Kolter, Roberto

2014-01-01

Salmonella Typhimurium inhabits a variety of environments and is able to infect a broad range of hosts. Throughout its life cycle, some hosts can act as intermediates in the path to the infection of others. Aspergillus niger is a ubiquitous fungus that can often be found in soil or associated to plants and microbial consortia. Recently, S. Typhimurium was shown to establish biofilms on the hyphae of A. niger. In this work, we have found that this interaction is stable for weeks without a noticeable negative effect on either organism. Indeed, bacterial growth is promoted upon the establishment of the interaction. Moreover, bacterial biofilms protect the fungus from external insults such as the effects of the anti-fungal agent cycloheximide. Thus, the Salmonella–Aspergillus interaction can be defined as mutualistic. A tripartite gnotobiotic system involving the bacterium, the fungus and a plant revealed that co-colonization has a greater negative effect on plant growth than colonization by either organism in dividually. Strikingly, co-colonization also causes a reduction in plant invasion by S. Typhimurium. This work demonstrates that S. Typhimurium and A. niger establish a mutualistic interaction that alters bacterial colonization of plants and affects plant physiology. PMID:25351041

Colorectal breast carcinoma metastasis diagnosed as an obstructive colonic primary tumor. A case report and review of the literature.

PubMed

Théraux, J; Bretagnol, F; Guedj, N; Cazals-Hatem, D; Panis, Y

2009-12-01

Common sites of colorectal breast carcinoma metastasis are bones, lungs, the central nervous system and the liver. Metastases in the gastrointestinal (GI) tract are rare and especially involve the stomach rather than the colon. Clinical or radiological features usually cannot differentiate them from a primary colorectal tumor, resulting in inappropriate treatment. In some cases, this lesion suggests multifocal spread of breast cancer with peritoneal carcinomatosis. Colorectal breast cancer metastasis is a rare finding and there is no consensus on the management of these lesions. The present case report describes a 69-year-old female with metastatic breast cancer presenting as an obstructive tumor of the transverse colon.

Differential Bacterial Colonization of Volcanic Minerals in Deep Thermal Basalts

NASA Astrophysics Data System (ADS)

Smith, A. R.; Popa, R.; Fisk, M. R.; Nielsen, M.; Wheat, G.; Jannasch, H.; Fisher, A.; Sievert, S.

2010-04-01

There are reports of microbial weathering patterns in volcanic glass and minerals of both terrestrial and Martian origin. Volcanic minerals are colonized differentially in subsurface hydrothermal environments by a variety of physiological types.

Ursodeoxycholic acid in patients with ulcerative colitis and primary sclerosing cholangitis for prevention of colon cancer: a meta-analysis.

PubMed

Ashraf, Imran; Choudhary, Abhishek; Arif, Murtaza; Matteson, Michelle L; Hammad, Hazem T; Puli, Srinivas R; Bechtold, Matthew L

2012-04-01

Colon cancer risk is high in patients with ulcerative colitis (UC) and primary sclerosing cholangitis (PSC). Ursodeoxycholic acid has been shown to have some promise as a chemopreventive agent. A meta-analysis was performed to compare the efficacy of ursodeoxycholic acid in the prevention of colonic neoplasia in patients with UC and PSC. Multiple databases were searched (January 2011). Studies examining the use of ursodeoxycholic acid vs. no ursodeoxycholic acid or placebo in adult patients with UC and PSC were included. Data were extracted in standard forms by two independent reviewers. Meta-analysis for the effect of ursodeoxycholic acid was performed by calculating pooled estimates of adenoma or colon cancer formation by odds ratio (OR) with random effects model. Heterogeneity was assessed by calculating the I (2) measure of inconsistency. RevMan 5 was utilized for statistical analysis. Four studies (n = 281) met the inclusion criteria. The studies were of adequate quality. Ursodeoxycholic acid demonstrated no overall improvement in adenoma (OR 0.53; 95 % CI: 0.19-1.48, p = 0.23) or colon cancer occurrence (OR 0.50; 95 % CI: 0.18-1.43, p = 0.20) as compared to no ursodeoxycholic acid or placebo in patients with UC and PSC. Ursodeoxycholic acid use in patients with UC and PSC does not appear to decrease the risk of adenomas or colon cancer.

Improving Outcomes Following Penetrating Colon Wounds

PubMed Central

Miller, Preston R.; Fabian, Timothy C.; Croce, Martin A.; Magnotti, Louis J.; Elizabeth Pritchard, F.; Minard, Gayle; Stewart, Ronald M.

2002-01-01

Introduction During World War II, failure to treat penetrating colon injuries with diversion could result in court martial. Based on this wartime experience, colostomy for civilian colon wounds became the standard of care for the next 4 decades. Previous work from our institution demonstrated that primary repair was the optimal management for nondestructive colon wounds. Optimal management of destructive wounds requiring resection remains controversial. To address this issue, we performed a study that demonstrated risk factors (pre or intraoperative transfusion requirement of more than 6 units of packed red blood cells, significant comorbid diseases) that were associated with a suture line failure rate of 14%, and of whom 33% died. Based on these outcomes, a clinical pathway for management of destructive colon wounds was developed. The results of the implementation of this pathway are the focus of this report. Methods Patients with penetrating colon injury were identified from the registry of a level I trauma center over a 5-year period. Records were reviewed for demographics, injury characteristics, and outcome. Patients with nondestructive injuries underwent primary repair. Patients with destructive wounds but no comorbidities or large transfusion requirement underwent resection and anastomosis, while patients with destructive wounds and significant medical illness or transfusion requirements of more than 6 units/blood received end colostomy. The current patients (CP) were compared to the previous study (PS) to determine the impact of the clinical pathway. Outcomes examined included colon related mortality and morbidity (suture line leak and abscess). Results Over a 5.5-year period, 231 patients had penetrating colon wounds. 209 survived more 24 hours and comprise the study population. Primary repair was performed on 153 (73%) patients, and 56 patients had destructive injuries (27%). Of these, 40 (71%) had resection and anastomosis and 16 (29%) had diversion

Seagrass (Zostera marina) Colonization Promotes the Accumulation of Diazotrophic Bacteria and Alters the Relative Abundances of Specific Bacterial Lineages Involved in Benthic Carbon and Sulfur Cycling

PubMed Central

Sun, Feifei; Zhang, Xiaoli; Zhang, Qianqian; Liu, Fanghua

2015-01-01

Seagrass colonization changes the chemistry and biogeochemical cycles mediated by microbes in coastal sediments. In this study, we molecularly characterized the diazotrophic assemblages and entire bacterial community in surface sediments of a Zostera marina-colonized coastal lagoon in northern China. Higher nitrogenase gene (nifH) copy numbers were detected in the sediments from the vegetated region than in the sediments from the unvegetated region nearby. The nifH phylotypes detected were mostly affiliated with the Geobacteraceae, Desulfobulbus, Desulfocapsa, and Pseudomonas. Redundancy analysis based on terminal restriction fragment length polymorphism analysis showed that the distribution of nifH genotypes was mostly shaped by the ratio of total organic carbon to total organic nitrogen, the concentration of cadmium in the sediments, and the pH of the overlying water. High-throughput sequencing and phylogenetic analyses of bacterial 16S rRNA genes also indicated the presence of Geobacteraceae and Desulfobulbaceae phylotypes in these samples. A comparison of these results with those of previous studies suggests the prevalence and predominance of iron(III)-reducing Geobacteraceae and sulfate-reducing Desulfobulbaceae diazotrophs in coastal sedimentary environments. Although the entire bacterial community structure was not significantly different between these two niches, Desulfococcus (Deltaproteobacteria) and Anaerolineae (Chloroflexi) presented with much higher proportions in the vegetated sediments, and Flavobacteriaceae (Bacteroidetes) occurred more frequently in the bare sediments. These data suggest that the high bioavailability of organic matter (indicated by relatively lower carbon-to-nitrogen ratios) and the less-reducing anaerobic condition in vegetated sediments may favor Desulfococcus and Anaerolineae lineages, which are potentially important populations in benthic carbon and sulfur cycling in the highly productive seagrass ecosystem. PMID:26209674

Seagrass (Zostera marina) Colonization Promotes the Accumulation of Diazotrophic Bacteria and Alters the Relative Abundances of Specific Bacterial Lineages Involved in Benthic Carbon and Sulfur Cycling.

PubMed

Sun, Feifei; Zhang, Xiaoli; Zhang, Qianqian; Liu, Fanghua; Zhang, Jianping; Gong, Jun

2015-10-01

Seagrass colonization changes the chemistry and biogeochemical cycles mediated by microbes in coastal sediments. In this study, we molecularly characterized the diazotrophic assemblages and entire bacterial community in surface sediments of a Zostera marina-colonized coastal lagoon in northern China. Higher nitrogenase gene (nifH) copy numbers were detected in the sediments from the vegetated region than in the sediments from the unvegetated region nearby. The nifH phylotypes detected were mostly affiliated with the Geobacteraceae, Desulfobulbus, Desulfocapsa, and Pseudomonas. Redundancy analysis based on terminal restriction fragment length polymorphism analysis showed that the distribution of nifH genotypes was mostly shaped by the ratio of total organic carbon to total organic nitrogen, the concentration of cadmium in the sediments, and the pH of the overlying water. High-throughput sequencing and phylogenetic analyses of bacterial 16S rRNA genes also indicated the presence of Geobacteraceae and Desulfobulbaceae phylotypes in these samples. A comparison of these results with those of previous studies suggests the prevalence and predominance of iron(III)-reducing Geobacteraceae and sulfate-reducing Desulfobulbaceae diazotrophs in coastal sedimentary environments. Although the entire bacterial community structure was not significantly different between these two niches, Desulfococcus (Deltaproteobacteria) and Anaerolineae (Chloroflexi) presented with much higher proportions in the vegetated sediments, and Flavobacteriaceae (Bacteroidetes) occurred more frequently in the bare sediments. These data suggest that the high bioavailability of organic matter (indicated by relatively lower carbon-to-nitrogen ratios) and the less-reducing anaerobic condition in vegetated sediments may favor Desulfococcus and Anaerolineae lineages, which are potentially important populations in benthic carbon and sulfur cycling in the highly productive seagrass ecosystem. Copyright © 2015

The effects of the time of intranasal splinting on bacterial colonization, postoperative complications, and patient discomfort after septoplasty operations.

PubMed

Karatas, Abdullah; Pehlivanoglu, Filiz; Salviz, Mehti; Kuvat, Nuray; Cebi, Isil Taylan; Dikmen, Burak; Sengoz, Gonul

The main reason for nasal tampon placement after septoplasty is to prevent postoperative hemorrhage, while the secondary purpose is internal stabilization after operations involving the cartilaginous-bony skeleton of the nose. Silicone intranasal splints are as successful as other materials in controlling postoperative hemorrhages of septal origin. The possibility of leaving the splints intranasally for extended periods helps stabilize the septum in the midline. However, there is nothing in the literature about how long these splints can be retained inside the nasal cavity without increasing the risk of infection, postoperative complications, and patient discomfort. The current study aimed to evaluate the association between the duration of intranasal splinting and bacterial colonization, postoperative complications, and patient discomfort. Patients who had undergone septoplasty were divided into three groups according to the day of removal of the silicone splints. The splints were removed on the fifth, seventh, and tenth postoperative days. The removed splints were microbiologically cultured. Early and late complications were assessed, including local and systemic infections, tissue necrosis, granuloma formation, mucosal crusting, synechia, and septal perforation. Postoperative patient discomfort was evaluated by scoring the levels of pain and nasal obstruction. No significant difference was found in the rate of bacterial colonization among the different groups. Decreased mucosal crusting and synechia were detected with longer usage intervals of intranasal silicone splints. Postoperative pain and nasal obstruction were also diminished by the third postoperative day. Silicone splints were well tolerated by the patients and any negative effects on postoperative patient comfort were limited. In fact, prolonged splint usage intervals reduced late complications. Long-term silicone nasal splint usage is a reliable, effective, and comfortable method in patients with

Enteric oxalate elimination is induced and oxalate is normalized in a mouse model of primary hyperoxaluria following intestinal colonization with Oxalobacter

PubMed Central

Gjymishka, Altin; Salido, Eduardo C.; Allison, Milton J.; Freel, Robert W.

2011-01-01

Oxalobacter colonization of rat intestine was previously shown to promote enteric oxalate secretion and elimination, leading to significant reductions in urinary oxalate excretion (Hatch et al. Kidney Int 69: 691–698, 2006). The main goal of the present study, using a mouse model of primary hyperoxaluria type 1 (PH1), was to test the hypothesis that colonization of the mouse gut by Oxalobacter formigenes could enhance enteric oxalate secretion and effectively reduce the hyperoxaluria associated with this genetic disease. Wild-type (WT) mice and mice deficient in liver alanine-glyoxylate aminotransferase (Agxt) exhibiting hyperoxalemia and hyperoxaluria were used in these studies. We compared the unidirectional and net fluxes of oxalate across isolated, short-circuited large intestine of artificially colonized and noncolonized mice. In addition, plasma and urinary oxalate was determined. Our results demonstrate that the cecum and distal colon contribute significantly to enteric oxalate excretion in Oxalobacter-colonized Agxt and WT mice. In colonized Agxt mice, urinary oxalate excretion was reduced 50% (to within the normal range observed for WT mice). Moreover, plasma oxalate concentrations in Agxt mice were also normalized (reduced 50%). Colonization of WT mice was also associated with marked (up to 95%) reductions in urinary oxalate excretion. We conclude that segment-specific effects of Oxalobacter on intestinal oxalate transport in the PH1 mouse model are associated with a normalization of plasma oxalate and urinary oxalate excretion in otherwise hyperoxalemic and hyperoxaluric animals. PMID:21163900

The role of respiratory viruses in the etiology of bacterial pneumonia

PubMed Central

Lee, Kyu Han; Gordon, Aubree; Foxman, Betsy

2016-01-01

Pneumonia is the leading cause of death among children less than 5 years old worldwide. A wide range of viral, bacterial and fungal agents can cause pneumonia: although viruses are the most common etiologic agent, the severity of clinical symptoms associated with bacterial pneumonia and increasing antibiotic resistance makes bacterial pneumonia a major public health concern. Bacterial pneumonia can follow upper respiratory viral infection and complicate lower respiratory viral infection. Secondary bacterial pneumonia is a major cause of influenza-related deaths. In this review, we evaluate the following hypotheses: (i) respiratory viruses influence the etiology of pneumonia by altering bacterial community structure in the upper respiratory tract (URT) and (ii) respiratory viruses promote or inhibit colonization of the lower respiratory tract (LRT) by certain bacterial species residing in the URT. We conducted a systematic review of the literature to examine temporal associations between respiratory viruses and bacteria and a targeted review to identify potential mechanisms of interactions. We conclude that viruses both alter the bacterial community in the URT and promote bacterial colonization of the LRT. However, it is uncertain whether changes in the URT bacterial community play a substantial role in pneumonia etiology. The exception is Streptococcus pneumoniae where a strong link between viral co-infection, increased carriage and pneumococcal pneumonia has been established. PMID:26884414

Insight into the bacterial gut microbiome of the North American moose (Alces alces)

PubMed Central

2012-01-01

Background The work presented here provides the first intensive insight into the bacterial populations in the digestive tract of the North American moose (Alces alces). Eight free-range moose on natural pasture were sampled, producing eight rumen samples and six colon samples. Second generation (G2) PhyloChips were used to determine the presence of hundreds of operational taxonomic units (OTUs), representing multiple closely related species/strains (>97% identity), found in the rumen and colon of the moose. Results A total of 789 unique OTUs were used for analysis, which passed the fluorescence and the positive fraction thresholds. There were 73 OTUs, representing 21 bacterial families, which were found exclusively in the rumen samples: Lachnospiraceae, Prevotellaceae and several unclassified families, whereas there were 71 OTUs, representing 22 bacterial families, which were found exclusively in the colon samples: Clostridiaceae, Enterobacteriaceae and several unclassified families. Overall, there were 164 OTUs that were found in 100% of the samples. The Firmicutes were the most dominant bacteria phylum in both the rumen and the colon. Microarray data available at ArrayExpress, accession number E-MEXP-3721. Conclusions Using PhyloTrac and UniFrac computer software, samples clustered into two distinct groups: rumen and colon, confirming that the rumen and colon are distinct environments. There was an apparent correlation of age to cluster, which will be validated by a larger sample size in future studies, but there were no detectable trends based upon gender. PMID:22992344

Campylobacter jejuni Colonization in Wild Birds: Results from an Infection Experiment

PubMed Central

Waldenström, Jonas; Axelsson-Olsson, Diana; Olsen, Björn; Hasselquist, Dennis; Griekspoor, Petra; Jansson, Lena; Teneberg, Susann; Svensson, Lovisa; Ellström, Patrik

2010-01-01

Campylobacter jejuni is a common cause of bacterial gastroenteritis in most parts of the world. The bacterium has a broad host range and has been isolated from many animals and environments. To investigate shedding patterns and putative effects on an avian host, we developed a colonization model in which a wild bird species, the European Robin Erithacus rubecula, was inoculated orally with C. jejuni from either a human patient or from another wild bird species, the Song Thrush Turdus philomelos. These two isolates were genetically distinct from each other and provoked very different host responses. The Song Thrush isolate colonized all challenged birds and colonization lasted 6.8 days on average. Birds infected with this isolate also showed a transient but significant decrease in body mass. The human isolate did not colonize the birds and could be detected only in the feces of the birds shortly after inoculation. European Robins infected with the wild bird isolate generated a specific antibody response to C. jejuni membrane proteins from the avian isolate, which also was cross-reactive to membrane proteins of the human isolate. In contrast, European Robins infected with the human isolate did not mount a significant response to bacterial membrane proteins from either of the two isolates. The difference in colonization ability could indicate host adaptations. PMID:20140204

Lower urinary tract infection and bacterial colonization in patient with double J ureteral stent.

PubMed

Joshi, R; Singh, D R; Sharma, S

2011-10-01

The aim of this study is to investigate the bacteriology of urinary tract infection associated with indwelling DJ stent. A total of 60 patients were included and 14 lost during follow up. Study period was for 6 months carried out in the department of surgery, Kathmandu Medical College. Prophylactic antibiotic was given at the time of intervention. Mid stream urine samples for routine and culture were sent before intervention. Urine samples during DJ removal and DJ tip cultures were also sent. All patients were "stented" during the various open and endourolgical procedures. Patients were clinically followed for a period till the DJ was removed. Statistical Package for Scientific Study (SPSS) 11, Chi square Test was used for statistical analysis. A total of 46 cases were included. Mean age in years was 35.70 (10-78 years). Male were 22 and female 24. Eleven patients (23.91%) had stent placed less than 30 days and 35 patients (76.08%) had it for equal or more than 30 days. DJ indwelling time was in between 12-86 days. Bacterial colonies were found in 28.3% (13 of 46) of the urine samples and 30.4% (14 of 46) from the tip of the DJ stent segment. Of the pathogens identified, E. coli was found to be the most common. An increased stent colonization rate was associated with implantation time, female sex. On urine culture 70.21% had no growth, 14.89% E. coli, 4.25% Klebsiella, Actinobacter, 2.12% E. coli/kleb, multiple org, psuedomonas. Ten patients (21.7%) had positive urine culture before stent insertion. Thirteen patients (28.3%) were shown to have positive urine culture on stent removal. Fourteen patients (30.4%) had positive DJ stent culture. Positive urine culture and positive DJ tip cultures had strong correlation. Longer duration of placement of stent showed stent colonization. The commonest pathogen was E. coli.

Pharyngeal colonization and drug resistance profiles of Morraxella catarrrhalis, Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae among HIV infected children attending ART Clinic of Felegehiwot Referral Hospital, Ethiopia.

PubMed

Mulu, Wondemagegn; Yizengaw, Endalew; Alemu, Megbaru; Mekonnen, Daniel; Hailu, Derese; Ketemaw, Kassaw; Abera, Bayeh; Kibret, Mulugeta

2018-01-01

Asymptomatic pharyngeal colonization by potential bacteria is the primary reservoir for bacterial species within a population and is considered a prerequisite for development of major childhood diseases such as sinusitis, otitis media, pneumonia, bacteremia, and meningitis. However, there is dearth of data on the colonization and drug resistance pattern of the main bacterial pathogens in the pharynx of HIV infected children in Ethiopia. Therefore, this study determined the pharyngeal colonization and drug resistance profile of bacterial pathogens in HIV infected children attending ART clinic of Felegehiwot Referral Hospital (FHRH), Amhara Region, Ethiopia. A hospital based cross-sectional study was conducted from May 2016 to June 2017 at the ART clinic of FHRH. A total of 300 HIV infected children were enrolled in the study. Data on socio-demographic characteristics of the study participants were collected with face-to-face interview and patient-card review using structured questionnaire. Bacterial species were identified using standard bacteriological techniques. Drug susceptibility testing was performed using disk diffusion technique. Chi-square test was done to determine associations among variables. The median age of the participants was 11 years. Overall, 153 (51%) of children were colonized by respiratory bacteria in their pharynx. Colonization rate was higher in children from mothers who had attained college and above levels of education than others (P = 0.04). It was also higher in children without the sign of malnutrition than others (P = 0.004). The colonization rate of S.aureus, M.catarrhalis, S.pneumoniae and H.influenzae were 88 (29%), 37 (12.3%), 31 (10.3%) and 6 (2%), respectively. S.aureus-M.catarrhalis concurrent colonization was found in 14 (4.7%) of children. Age (P = 0.03), schooling (P = 0.045) and history of running nose (P = 0.043) were significantly associated with S.aureus colonization. Living in urban setting (P = 0.042) and children from

Tracking Bioluminescent ETEC during In vivo BALB/c Mouse Colonization

PubMed Central

Rodea, Gerardo E.; Montiel-Infante, Francisco X.; Cruz-Córdova, Ariadnna; Saldaña-Ahuactzi, Zeus; Ochoa, Sara A.; Espinosa-Mazariego, Karina; Hernández-Castro, Rigoberto; Xicohtencatl-Cortes, Juan

2017-01-01

Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrhea worldwide. Adhesion to the human intestinal tract is crucial for colonization. ETEC adhesive structures have been extensively studied; however, colonization dynamics remain uncharacterized. The aim of this study was to track bioluminescent ETEC during in vivo infection. The promoter region of dnaK was fused with the luc gene, resulting in the pRMkluc vector. E. coli K-12 and ETEC FMU073332 strains were electroporated with pRMkluc. E. coli K-12 pRMkluc was bioluminescent; in contrast, the E. coli K-12 control strain did not emit bioluminescence. The highest light emission was measured at 1.9 OD600 (9 h) and quantified over time. The signal was detected starting at time 0 and up to 12 h. Streptomycin-treated BALB/c mice were orogastrically inoculated with either ETEC FMU073332 pRMkluc or E. coli K-12 pRMkluc (control), and bacterial colonization was determined by measuring bacterial shedding in the feces. ETEC FMU073332 pRMkluc shedding started and stopped after inoculation of the control strain, indicating that mouse intestinal colonization by ETEC FMU073332 pRMkluc lasted longer than colonization by the control. The bioluminescence signal of ETEC FMU073332 pRMkluc was captured starting at the time of inoculation until 12 h after inoculation. The bioluminescent signal emitted by ETEC FMU073332 pRMkluc in the proximal mouse ileum was located, and the control signal was identified in the cecum. The detection of maximal light emission and bioluminescence duration allowed us to follow ETEC during in vivo infection. ETEC showed an enhanced colonization and tropism in the mouse intestine compared with those in the control strain. Here, we report the first study of ETEC colonization in the mouse intestine accompanied by in vivo imaging. PMID:28560186

[Submucosal bacterial abscesses of the ascending colon and liver associated with portal and superior mesenteric vein thrombosis due to Enterococcus faecalis infection: a case report].

PubMed

Norimura, Daisuke; Takeshima, Fuminao; Satou, Yoshiaki; Nakagoe, Tohru; Ohnita, Ken; Isomoto, Hajime; Nakao, Kazuhiko

2014-06-01

A 72-year-old woman with diabetes mellitus was admitted with fever and general fatigue. Blood biochemistry showed elevated hepatic and biliary enzyme levels, abdominal computed tomography showed multiple liver abscesses with portal and superior mesenteric vein thrombosis, and total colonoscopy revealed a submucosal bacterial abscess in the ascending colon. The abscesses were determined to be associated with Enterococcus faecalis infection. The patient was treated conservatively with antibiotics (meropenem) and anticoagulants (warfarin), which led to a gradual amelioration of symptoms and resolution of thrombosis.

Sequential colonization of periodontal pathogens in induction of periodontal disease and atherosclerosis in LDLRnull mice.

PubMed

Chukkapalli, Sasanka S; Easwaran, Meena; Rivera-Kweh, Mercedes F; Velsko, Irina M; Ambadapadi, Sriram; Dai, Jiayin; Larjava, Hannu; Lucas, Alexandra R; Kesavalu, Lakshmyya

2017-01-01

Periodontal disease (PD) and atherosclerotic vascular disease (ASVD) are both chronic inflammatory diseases with a polymicrobial etiology and have been epidemiologically associated. The purpose is to examine whether periodontal bacteria that infect the periodontium can also infect vascular tissues and enhance pre-existing early aortic atherosclerotic lesions in LDLRnull mice. Mice were orally infected with intermediate bacterial colonizer Fusobacterium nucleatum for the first 12 weeks followed by late bacterial colonizers (Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia) for the remaining 12 weeks mimicking the human oral microbiota ecological colonization. Genomic DNA from all four bacterial was detected in gingival plaque by PCR, consistently demonstrating infection of mouse gingival surfaces. Infected mice had significant levels of IgG and IgM antibodies, alveolar bone resorption, and showed apical migration of junctional epithelium revealing the induction of PD. These results support the ability of oral bacteria to cause PD in mice. Detection of bacterial genomic DNA in systemic organs indicates hematogenous dissemination from the gingival pockets. Bacterial infection did not alter serum lipid fractions or serum amyloid A levels and did not induce aortic atherosclerotic plaque. This is the first study examining the causal role of periodontal bacteria in induction of ASVD in LDLRnull mice. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Effect of water flow and chemical environment on microbiota growth and composition in the human colon.

PubMed

Cremer, Jonas; Arnoldini, Markus; Hwa, Terence

2017-06-20

The human gut harbors a dynamic microbial community whose composition bears great importance for the health of the host. Here, we investigate how colonic physiology impacts bacterial growth, which ultimately dictates microbiota composition. Combining measurements of bacterial physiology with analysis of published data on human physiology into a quantitative, comprehensive modeling framework, we show how water flow in the colon, in concert with other physiological factors, determine the abundances of the major bacterial phyla. Mechanistically, our model shows that local pH values in the lumen, which differentially affect the growth of different bacteria, drive changes in microbiota composition. It identifies key factors influencing the delicate regulation of colonic pH, including epithelial water absorption, nutrient inflow, and luminal buffering capacity, and generates testable predictions on their effects. Our findings show that a predictive and mechanistic understanding of microbial ecology in the gut is possible. Such predictive understanding is needed for the rational design of intervention strategies to actively control the microbiota.

Effect of water flow and chemical environment on microbiota growth and composition in the human colon

PubMed Central

Cremer, Jonas; Arnoldini, Markus; Hwa, Terence

2017-01-01

The human gut harbors a dynamic microbial community whose composition bears great importance for the health of the host. Here, we investigate how colonic physiology impacts bacterial growth, which ultimately dictates microbiota composition. Combining measurements of bacterial physiology with analysis of published data on human physiology into a quantitative, comprehensive modeling framework, we show how water flow in the colon, in concert with other physiological factors, determine the abundances of the major bacterial phyla. Mechanistically, our model shows that local pH values in the lumen, which differentially affect the growth of different bacteria, drive changes in microbiota composition. It identifies key factors influencing the delicate regulation of colonic pH, including epithelial water absorption, nutrient inflow, and luminal buffering capacity, and generates testable predictions on their effects. Our findings show that a predictive and mechanistic understanding of microbial ecology in the gut is possible. Such predictive understanding is needed for the rational design of intervention strategies to actively control the microbiota. PMID:28588144

Effect of nematodes on rhizosphere colonization by seed-applied bacteria.

PubMed

Knox, Oliver G G; Killham, Ken; Artz, Rebekka R E; Mullins, Chris; Wilson, Michael

2004-08-01

There is much interest in the use of seed-applied bacteria for biocontrol and biofertilization, and several commercial products are available. However, many attempts to use this strategy fail because the seed-applied bacteria do not colonize the rhizosphere. Mechanisms of rhizosphere colonization may involve active bacterial movement or passive transport by percolating water or plant roots. Transport by other soil biota is likely to occur, but this area has not been well studied. We hypothesized that interactions with soil nematodes may enhance colonization. To test this hypothesis, a series of microcosm experiments was carried out using two contrasting soils maintained under well-defined physical conditions where transport by mass water flow could not occur. Seed-applied Pseudomonas fluorescens SBW25 was capable of rhizosphere colonization at matric potentials of -10 and -40 kPa in soil without nematodes, but colonization levels were substantially increased by the presence of nematodes. Our results suggest that nematodes can have an important role in rhizosphere colonization by bacteria in soil.

Molecular analysis of the microbial diversity present in the colonic wall, colonic lumen, and cecal lumen of a pig.

PubMed

Pryde, S E; Richardson, A J; Stewart, C S; Flint, H J

1999-12-01

Random clones of 16S ribosomal DNA gene sequences were isolated after PCR amplification with eubacterial primers from total genomic DNA recovered from samples of the colonic lumen, colonic wall, and cecal lumen from a pig. Sequences were also obtained for cultures isolated anaerobically from the same colonic-wall sample. Phylogenetic analysis showed that many sequences were related to those of Lactobacillus or Streptococcus spp. or fell into clusters IX, XIVa, and XI of gram-positive bacteria. In addition, 59% of randomly cloned sequences showed less than 95% similarity to database entries or sequences from cultivated organisms. Cultivation bias is also suggested by the fact that the majority of isolates (54%) recovered from the colon wall by culturing were related to Lactobacillus and Streptococcus, whereas this group accounted for only one-third of the sequence variation for the same sample from random cloning. The remaining cultured isolates were mainly Selenomonas related. A higher proportion of Lactobacillus reuteri-related sequences than of Lactobacillus acidophilus- and Lactobacillus amylovorus-related sequences were present in the colonic-wall sample. Since the majority of bacterial ribosomal sequences recovered from the colon wall are less than 95% related to known organisms, the roles of many of the predominant wall-associated bacteria remain to be defined.

Molecular Analysis of the Microbial Diversity Present in the Colonic Wall, Colonic Lumen, and Cecal Lumen of a Pig

PubMed Central

Pryde, Susan E.; Richardson, Anthony J.; Stewart, Colin S.; Flint, Harry J.

1999-01-01

Random clones of 16S ribosomal DNA gene sequences were isolated after PCR amplification with eubacterial primers from total genomic DNA recovered from samples of the colonic lumen, colonic wall, and cecal lumen from a pig. Sequences were also obtained for cultures isolated anaerobically from the same colonic-wall sample. Phylogenetic analysis showed that many sequences were related to those of Lactobacillus or Streptococcus spp. or fell into clusters IX, XIVa, and XI of gram-positive bacteria. In addition, 59% of randomly cloned sequences showed less than 95% similarity to database entries or sequences from cultivated organisms. Cultivation bias is also suggested by the fact that the majority of isolates (54%) recovered from the colon wall by culturing were related to Lactobacillus and Streptococcus, whereas this group accounted for only one-third of the sequence variation for the same sample from random cloning. The remaining cultured isolates were mainly Selenomonas related. A higher proportion of Lactobacillus reuteri-related sequences than of Lactobacillus acidophilus- and Lactobacillus amylovorus-related sequences were present in the colonic-wall sample. Since the majority of bacterial ribosomal sequences recovered from the colon wall are less than 95% related to known organisms, the roles of many of the predominant wall-associated bacteria remain to be defined. PMID:10583991

Streptococcus Adherence and Colonization

PubMed Central

Nobbs, Angela H.; Lamont, Richard J.; Jenkinson, Howard F.

2009-01-01

Summary: Streptococci readily colonize mucosal tissues in the nasopharynx; the respiratory, gastrointestinal, and genitourinary tracts; and the skin. Each ecological niche presents a series of challenges to successful colonization with which streptococci have to contend. Some species exist in equilibrium with their host, neither stimulating nor submitting to immune defenses mounted against them. Most are either opportunistic or true pathogens responsible for diseases such as pharyngitis, tooth decay, necrotizing fasciitis, infective endocarditis, and meningitis. Part of the success of streptococci as colonizers is attributable to the spectrum of proteins expressed on their surfaces. Adhesins enable interactions with salivary, serum, and extracellular matrix components; host cells; and other microbes. This is the essential first step to colonization, the development of complex communities, and possible invasion of host tissues. The majority of streptococcal adhesins are anchored to the cell wall via a C-terminal LPxTz motif. Other proteins may be surface anchored through N-terminal lipid modifications, while the mechanism of cell wall associations for others remains unclear. Collectively, these surface-bound proteins provide Streptococcus species with a “coat of many colors,” enabling multiple intimate contacts and interplays between the bacterial cell and the host. In vitro and in vivo studies have demonstrated direct roles for many streptococcal adhesins as colonization or virulence factors, making them attractive targets for therapeutic and preventive strategies against streptococcal infections. There is, therefore, much focus on applying increasingly advanced molecular techniques to determine the precise structures and functions of these proteins, and their regulatory pathways, so that more targeted approaches can be developed. PMID:19721085

Bacterial adherence in the pathogenesis of urinary tract infection: a review.

PubMed

Reid, G; Sobel, J D

1987-01-01

Bacterial adherence to the uroepithelium is recognized as an important mechanism in the initiation and pathogenesis of urinary tract infections (UTI). The uropathogens originate predominantly in the intestinal tract and initially colonize the periurethral region and ascend into the bladder, resulting in symptomatic or asymptomatic bacteriuria. Thereafter, depending on host factors and bacterial virulence factors, the organisms may further ascend and give rise to pyelonephritis. Uropathogens are selected by the presence of virulence characteristics that enable them to resist the normally efficient host defense mechanisms. Considerable progress has been made in identifying bacterial adhesins and in demonstrating bacterial receptor sites on uroepithelial surfaces. Recent studies have identified natural anti-adherence mechanisms in humans as well as possible increased susceptibility to UTI when these mechanisms are defective and when receptor density on uroepithelial cells is altered. Knowledge of bacterial adherence mechanisms may permit alternative methods of prevention and management of urinary infection, including the use of subinhibitory concentrations of antibiotics, vaccine development, nonimmune inhibition of bacterial adhesins and receptor sites, and the use of autochthonous flora, such as lactobacilli, to exclude uropathogens from colonizing the urinary tract.

Emergency management of acute colonic cancer obstruction.

PubMed

Gainant, A

2012-02-01

Emergency management of obstructing colonic cancer depends on both tumor location and stage, general condition of the patient and surgeon's experience. Right sided or transverse colon obstructing cancers are usually treated by right hemicolectomy-extended if necessary to the transverse colon-with primary anastomosis. For left-sided obstructing cancer, in patients with low surgical risk, primary resection and anastomosis associated with on-table irrigation or manual decompression can be performed. It prevents the confection of a loop colostomy but presents the risk of anastomotic leakage. Subtotal or total colectomy allows the surgeon to encompass distended and fecal-loaded colon, and to perform one-stage resection and anastomosis. Its disadvantage is an increased daily frequency of stools. It must be performed only in cases of diastatic colon perforation or synchronous right colonic cancer. In patients with high surgical risk, Hartmann procedure must be preferred. It allows the treatment of both obstruction and cancer, and prevents anastomotic leakage but needs a second operation to reverse the colostomy. Colonic stenting is clinically successful in up to 90% in specialized groups. It is used as palliation in patients with disseminated disease or bridge to surgery in the others. If stent insertion is not possible, loop colostomy is still indicated in patients at high surgical risk. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Tracking microbial colonization in fecal microbiota transplantation experiments via genome-resolved metagenomics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Sonny T. M.; Kahn, Stacy A.; Delmont, Tom O.

Fecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection and shows promise for treating other medical conditions associated with intestinal dysbioses. However, we lack a sufficient understanding of which microbial populations successfully colonize the recipient gut, and the widely used approaches to study the microbial ecology of FMT experiments fail to provide enough resolution to identify populations that are likely responsible for FMT-derived benefits. Here, we used shotgun metagenomics together with assembly and binning strategies to reconstruct metagenome-assembled genomes (MAGs) from fecal samples of a single FMT donor. We then used metagenomic mapping to track themore » occurrence and distribution patterns of donor MAGs in two FMT recipients. Our analyses revealed that 22% of the 92 highly complete bacterial MAGs that we identified from the donor successfully colonized and remained abundant in two recipients for at least 8 weeks. Most MAGs with a high colonization rate belonged to the order Bacteroidales. The vast majority of those that lacked evidence of colonization belonged to the order Clostridiales, and colonization success was negatively correlated with the number of genes related to sporulation. Our analysis of 151 publicly available gut metagenomes showed that the donor MAGs that colonized both recipients were prevalent, and the ones that colonized neither were rare across the participants of the Human Microbiome Project. Although our dataset showed a link between taxonomy and the colonization ability of a given MAG, we also identified MAGs that belong to the same taxon with different colonization properties, highlighting the importance of an appropriate level of resolution to explore the functional basis of colonization and to identify targets for cultivation, hypothesis generation, and testing in model systems. Lastly, the analytical strategy adopted in our study can provide genomic insights

Tracking microbial colonization in fecal microbiota transplantation experiments via genome-resolved metagenomics

DOE PAGES

Lee, Sonny T. M.; Kahn, Stacy A.; Delmont, Tom O.; ...

2017-05-04

Fecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection and shows promise for treating other medical conditions associated with intestinal dysbioses. However, we lack a sufficient understanding of which microbial populations successfully colonize the recipient gut, and the widely used approaches to study the microbial ecology of FMT experiments fail to provide enough resolution to identify populations that are likely responsible for FMT-derived benefits. Here, we used shotgun metagenomics together with assembly and binning strategies to reconstruct metagenome-assembled genomes (MAGs) from fecal samples of a single FMT donor. We then used metagenomic mapping to track themore » occurrence and distribution patterns of donor MAGs in two FMT recipients. Our analyses revealed that 22% of the 92 highly complete bacterial MAGs that we identified from the donor successfully colonized and remained abundant in two recipients for at least 8 weeks. Most MAGs with a high colonization rate belonged to the order Bacteroidales. The vast majority of those that lacked evidence of colonization belonged to the order Clostridiales, and colonization success was negatively correlated with the number of genes related to sporulation. Our analysis of 151 publicly available gut metagenomes showed that the donor MAGs that colonized both recipients were prevalent, and the ones that colonized neither were rare across the participants of the Human Microbiome Project. Although our dataset showed a link between taxonomy and the colonization ability of a given MAG, we also identified MAGs that belong to the same taxon with different colonization properties, highlighting the importance of an appropriate level of resolution to explore the functional basis of colonization and to identify targets for cultivation, hypothesis generation, and testing in model systems. Lastly, the analytical strategy adopted in our study can provide genomic insights

Anti-Pseudomonas aeruginosa IgY Antibodies Induce Specific Bacterial Aggregation and Internalization in Human Polymorphonuclear Neutrophils

PubMed Central

Thomsen, K.; Christophersen, L.; Bjarnsholt, T.; Jensen, P. Ø.; Moser, C.

2015-01-01

Polymorphonuclear neutrophils (PMNs) are essential cellular constituents in the innate host response, and their recruitment to the lungs and subsequent ubiquitous phagocytosis controls primary respiratory infection. Cystic fibrosis pulmonary disease is characterized by progressive pulmonary decline governed by a persistent, exaggerated inflammatory response dominated by PMNs. The principal contributor is chronic Pseudomonas aeruginosa biofilm infection, which attracts and activates PMNs and thereby is responsible for the continuing inflammation. Strategies to prevent initial airway colonization with P. aeruginosa by augmenting the phagocytic competence of PMNs may postpone the deteriorating chronic biofilm infection. Anti-P. aeruginosa IgY antibodies significantly increase the PMN-mediated respiratory burst and subsequent bacterial killing of P. aeruginosa in vitro. The mode of action is attributed to IgY-facilitated formation of immobilized bacteria in aggregates, as visualized by fluorescence microscopy and the induction of increased bacterial hydrophobicity. Thus, the present study demonstrates that avian egg yolk immunoglobulins (IgY) targeting P. aeruginosa modify bacterial fitness, which enhances bacterial killing by PMN-mediated phagocytosis and thereby may facilitate a rapid bacterial clearance in airways of people with cystic fibrosis. PMID:25895968

Maternal Antibiotic-Induced Early Changes in Microbial Colonization Selectively Modulate Colonic Permeability and Inducible Heat Shock Proteins, and Digesta Concentrations of Alkaline Phosphatase and TLR-Stimulants in Swine Offspring

PubMed Central

Arnal, Marie-Edith; Zhang, Jing; Erridge, Clett; Smidt, Hauke; Lallès, Jean-Paul

2015-01-01

Elevated intake of high energy diets is a risk factor for the development of metabolic diseases and obesity. High fat diets cause alterations in colonic microbiota composition and increase gut permeability to bacterial lipopolysaccharide, and subsequent low-grade chronic inflammation in mice. Chronic inflammatory bowel diseases are increasing worldwide and may involve alterations in microbiota-host dialog. Metabolic disorders appearing in later life are also suspected to reflect changes in early programming. However, how the latter affects the colon remains poorly studied. Here, we hypothesized that various components of colonic physiology, including permeability, ion exchange and protective inducible heat shock proteins (HSP) are influenced in the short- and long-terms by early disturbances in microbial colonization. The hypothesis was tested in a swine model. Offspring were born to control mothers (n = 12) or mothers treated with the antibiotic (ATB) amoxicillin around parturition (n = 11). Offspring were slaughtered between 14 and 42 days of age to study short-term effects. For long-term effects, young adult offspring from the same litters consumed a normal or a palm oil-enriched diet for 4 weeks between 140 and 169 days of age. ATB treatment transiently modified maternal fecal microbiota although the minor differences observed for offspring colonic microbiota were nonsignificant. In the short-term, consistently higher HSP27 and HSP70 levels and transiently increased horseradish peroxidase permeability in ATB offspring colon were observed. Importantly, long-term consequences included reduced colonic horseradish peroxidase permeability, and increased colonic digesta alkaline phosphatase (AP) and TLR2- and TLR4-stimulant concentrations in rectal digesta in adult ATB offspring. Inducible HSP27 and HSP70 did not change. Interactions between early ATB treatment and later diet were noted for paracellular permeability and concentrations of colonic digesta AP. In

Maternal antibiotic-induced early changes in microbial colonization selectively modulate colonic permeability and inducible heat shock proteins, and digesta concentrations of alkaline phosphatase and TLR-stimulants in swine offspring.

PubMed

Arnal, Marie-Edith; Zhang, Jing; Erridge, Clett; Smidt, Hauke; Lallès, Jean-Paul

2015-01-01

Elevated intake of high energy diets is a risk factor for the development of metabolic diseases and obesity. High fat diets cause alterations in colonic microbiota composition and increase gut permeability to bacterial lipopolysaccharide, and subsequent low-grade chronic inflammation in mice. Chronic inflammatory bowel diseases are increasing worldwide and may involve alterations in microbiota-host dialog. Metabolic disorders appearing in later life are also suspected to reflect changes in early programming. However, how the latter affects the colon remains poorly studied. Here, we hypothesized that various components of colonic physiology, including permeability, ion exchange and protective inducible heat shock proteins (HSP) are influenced in the short- and long-terms by early disturbances in microbial colonization. The hypothesis was tested in a swine model. Offspring were born to control mothers (n = 12) or mothers treated with the antibiotic (ATB) amoxicillin around parturition (n = 11). Offspring were slaughtered between 14 and 42 days of age to study short-term effects. For long-term effects, young adult offspring from the same litters consumed a normal or a palm oil-enriched diet for 4 weeks between 140 and 169 days of age. ATB treatment transiently modified maternal fecal microbiota although the minor differences observed for offspring colonic microbiota were nonsignificant. In the short-term, consistently higher HSP27 and HSP70 levels and transiently increased horseradish peroxidase permeability in ATB offspring colon were observed. Importantly, long-term consequences included reduced colonic horseradish peroxidase permeability, and increased colonic digesta alkaline phosphatase (AP) and TLR2- and TLR4-stimulant concentrations in rectal digesta in adult ATB offspring. Inducible HSP27 and HSP70 did not change. Interactions between early ATB treatment and later diet were noted for paracellular permeability and concentrations of colonic digesta AP. In

Historical and Current Trends in Colon Trauma

PubMed Central

Causey, Marlin Wayne; Rivadeneira, David E.; Steele, Scott R.

2012-01-01

The authors discuss the evolution of the evaluation and management of colonic trauma, as well as the debate regarding primary repair versus fecal diversion. Their evidence-based review covers diagnosis, management, surgical approaches, and perioperative care of patients with colon-related trauma. The management of traumatic colon injuries has evolved significantly over the past 50 years; here the authors describe a practical approach to the treatment and management of traumatic injuries to the colon based on the most current research. However, management of traumatic colon injuries remains a challenge and continues to be associated with significant morbidity. Familiarity with the different methods to the approach and management of colonic injuries will allow surgeons to minimize unnecessary complications and mortality. PMID:24294119

Changes of Colonic Bacterial Composition in Parkinson's Disease and Other Neurodegenerative Diseases.

PubMed

Gerhardt, Sara; Mohajeri, M Hasan

2018-06-01

In recent years evidence has emerged that neurodegenerative diseases (NDs) are strongly associated with the microbiome composition in the gut. Parkinson's disease (PD) is the most intensively studied neurodegenerative disease in this context. In this review, we performed a systematic evaluation of the published literature comparing changes in colonic microbiome in PD to the ones observed in other NDs including Alzheimer's disease (AD), multiple system atrophy (MSA), multiple sclerosis (MS), neuromyelitis optica (NMO) and amyotrophic lateral sclerosis (ALS). To enhance the comparability of different studies, only human case-control studies were included. Several studies showed an increase of Lactobacillus , Bifidobacterium , Verrucomicrobiaceae and Akkermansia in PD. A decrease of Faecalibacterium spp., Coprococcus spp., Blautia spp., Prevotella spp. and Prevotellaceae was observed in PD. On a low taxonomic resolution, like the phylum level, the changes are not disease-specific and are inconsistent. However, on a higher taxonomic resolution like genus or species level, a minor overlap was observed between PD and MSA, both alpha synucleinopathies. We show that standardization of sample collection and analysis is necessary for ensuring the reproducibility and comparability of data. We also provide evidence that assessing the microbiota composition at high taxonomic resolution reveals changes in relative abundance that may be specific to or characteristic of one disease or disease group, and might evolve discriminative power. The interactions between bacterial species and strains and the co-abundances must be investigated before assumptions about the effects of specific bacteria on the host can be made with certainty.

Colon Cancer Treatment (PDQ®)—Health Professional Version

Cancer.gov

Colon cancer treatment often involves open surgical resection as the primary treatment for localized disease. Other modalities include chemotherapy, targeted therapy, radiation therapy, and local ablation. Get detailed information about colon cancer treatment in this summary for clinicians.

A ten-year study of penetrating injuries of the colon.

PubMed

Adesanya, Adedoyin A; Ekanem, Ekanem E

2004-12-01

Colon injury has been associated with a high risk of septic complications and mortality. We prospectively studied the pattern, management, outcome, and prognostic factors in patients who sustained penetrating colon injuries. Sixty patients who presented to our hospital with penetrating colon injuries over a ten-year period (1992 to 2001) were studied. Colon wounds were caused by gunshots in 55 (91.7 percent) patients and knife stabs in 5 (8.3 percent). There was a delay of more than 12 hours before laparotomy in 30 (50 percent) patients. Moderate or major fecal contamination of the peritoneal cavity occurred in 58 (96.7 percent) patients. The average penetrating abdominal trauma index score was 25.9 and 20 (33.3 percent) patients sustained Flint Grade 3 colon injury. Associated intra-abdominal injuries occurred in the small bowel (73.3 percent), liver (25 percent), stomach (23.3 percent), and mesentery (16.7 percent). Right colon wounds (35) were managed by primary repair in 24 (68.6 percent) patients and proximal diverting colostomy in 11 (31.4 percent), whereas left colon wounds (25) were managed by diverting colostomy in 22 (88.0 percent) patients and primary repair in 3 (12.0 percent) patients. Common complications included wound infection (56.7 percent), septicemia (31.7 percent), and enterocutaneous fistula (16.7 percent). The overall mortality rate was 33.3 percent and colon injury-related mortality was 21.7 percent. Presence of destructive colon injury was associated with a greater than fourfold increased incidence of death. Other significant risk factors included shock on admission, major fecal contamination, duration of operation more than four hours, penetrating abdominal trauma index score >25, and more than two postoperative complications. There was no difference in outcome between patients who had primary repair and those undergoing diverting colostomy. Colostomy closure-related morbidity was 21 percent and mortality was 5.3 percent. A more liberal

Variation in primary site resection practices for advanced colon cancer: a study using the National Cancer Data Base.

PubMed

Healy, Mark A; Pradarelli, Jason C; Krell, Robert W; Regenbogen, Scott E; Suwanabol, Pasithorn A

2016-10-01

Treatment of metastatic colon cancer may be driven as much by practice patterns as by features of disease. To optimize management, there is a need to better understand what is determining primary site resection use. We evaluated all patients with stage IV cancers in the National Cancer Data Base from 2002 to 2012 (50,791 patients, 1,230 hospitals). We first identified patient characteristics associated with primary tumor resection. Then, we assessed nationwide variation in hospital resection rates. Overall, 27,387 (53.9%) patients underwent primary site resection. Factors associated with resection included younger age, having less than 2 major comorbidities, and white race (P < .001). Nationwide, hospital-adjusted primary tumor resection rates ranged from 26.0% to 87.8% with broad differences across geographical areas and hospital accreditation types. There is statistically significant variation in hospital rates of primary site resection. This demonstrates inconsistent adherence to guidelines in the presence of conflicting evidence regarding resection benefit. Copyright © 2016 Elsevier Inc. All rights reserved.

Factors that mediate colonization of the human stomach by Helicobacter pylori.

PubMed

Dunne, Ciara; Dolan, Brendan; Clyne, Marguerite

2014-05-21

Helicobacter pylori (H. pylori) colonizes the stomach of humans and causes chronic infection. The majority of bacteria live in the mucus layer overlying the gastric epithelial cells and only a small proportion of bacteria are found interacting with the epithelial cells. The bacteria living in the gastric mucus may act as a reservoir of infection for the underlying cells which is essential for the development of disease. Colonization of gastric mucus is likely to be key to the establishment of chronic infection. How H. pylori manages to colonise and survive in the hostile environment of the human stomach and avoid removal by mucus flow and killing by gastric acid is the subject of this review. We also discuss how bacterial and host factors may together go some way to explaining the susceptibility to colonization and the outcome of infection in different individuals. H. pylori infection of the gastric mucosa has become a paradigm for chronic infection. Understanding of why H. pylori is such a successful pathogen may help us understand how other bacterial species colonise mucosal surfaces and cause disease.

Factors that mediate colonization of the human stomach by Helicobacter pylori

PubMed Central

Dunne, Ciara; Dolan, Brendan; Clyne, Marguerite

2014-01-01

Helicobacter pylori (H. pylori) colonizes the stomach of humans and causes chronic infection. The majority of bacteria live in the mucus layer overlying the gastric epithelial cells and only a small proportion of bacteria are found interacting with the epithelial cells. The bacteria living in the gastric mucus may act as a reservoir of infection for the underlying cells which is essential for the development of disease. Colonization of gastric mucus is likely to be key to the establishment of chronic infection. How H. pylori manages to colonise and survive in the hostile environment of the human stomach and avoid removal by mucus flow and killing by gastric acid is the subject of this review. We also discuss how bacterial and host factors may together go some way to explaining the susceptibility to colonization and the outcome of infection in different individuals. H. pylori infection of the gastric mucosa has become a paradigm for chronic infection. Understanding of why H. pylori is such a successful pathogen may help us understand how other bacterial species colonise mucosal surfaces and cause disease. PMID:24914320

Nasopharyngeal bacterial burden and antibiotics: Influence on inflammatory markers and disease severity in infants with respiratory syncytial virus bronchiolitis.

PubMed

Suárez-Arrabal, M Carmen; Mella, Cesar; Lopez, Santiago M; Brown, Nicole V; Hall, Mark W; Hammond, Sue; Shiels, William; Groner, Judith; Marcon, Mario; Ramilo, Octavio; Mejias, Asuncion

2015-10-01

Animal studies suggest that RSV increases nasopharyngeal (NP) bacterial colonization facilitating bacterial infections. We investigated the influence of antibiotic treatment and colonization with potentially pathogenic bacteria on inflammatory markers and disease severity in RSV-infected in infants. Healthy young infants hospitalized with RSV bronchiolitis (n = 136) and age-matched healthy controls (n = 23) were enrolled and NP samples cultured for potentially pathogenic bacteria including: Gram-positive bacteria (GPB): Staphylococcus aureus, Streptococcus pneumoniae, β-hemolytic Streptococcus; and Gram-negative bacteria (GNB): Moraxella catarrhalis and Haemophilus influenzae. Clinical parameters and plasma IL-8, IL-6 and TNF-α concentrations were compared according to the bacterial class and antibiotic treatment. Antibiotic treatment decreased by 10-fold NP bacterial recovery. Eighty-one percent of RSV infants who did not receive antibiotics before sample collection were colonized with pathogenic bacteria. Overall, GNB were identified in 21% of patients versus 4% of controls who were mostly colonized with GPB. Additionally, in RSV patients NP white blood cell counts (p = 0.026), and blood neutrophils (p = 0.02) were higher in those colonized with potentially pathogenic bacteria versus respiratory flora. RSV patients colonized with GNB had higher plasma IL-8 (p = 0.01) and IL-6 (p < 0.01) concentrations than controls, and required longer duration of oxygen (p = 0.049). Infants with RSV bronchiolitis colonized with potentially pathogenic bacteria had increased numbers of mucosal and systemic inflammatory cells. Specifically, colonization with GNB was associated with higher concentrations of proinflammatory cytokines and a trend towards increased disease severity. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Streptococcus pneumoniae Colonization Is Required To Alter the Nasal Microbiota in Cigarette Smoke-Exposed Mice

PubMed Central

Shen, Pamela; Whelan, Fiona J.; Schenck, L. Patrick; McGrath, Joshua J. C.; Vanderstocken, Gilles; Bowdish, Dawn M. E.; Surette, Michael G.

2017-01-01

ABSTRACT Smokers have nasal microbiota dysbiosis, with an increased frequency of colonizing bacterial pathogens. It is possible that cigarette smoke increases pathogen acquisition by perturbing the microbiota and decreasing colonization resistance. However, it is difficult to disentangle microbiota dysbiosis due to cigarette smoke exposure from microbiota changes caused by increased pathogen acquisition in human smokers. Using an experimental mouse model, we investigated the impact of cigarette smoke on the nasal microbiota in the absence and presence of nasal pneumococcal colonization. We observed that cigarette smoke exposure alone did not alter the nasal microbiota composition. The microbiota composition was also unchanged at 12 h following low-dose nasal pneumococcal inoculation, suggesting that the ability of the microbiota to resist initial nasal pneumococcal acquisition was not impaired in smoke-exposed mice. However, nasal microbiota dysbiosis occurred as a consequence of established high-dose nasal pneumococcal colonization at day 3 in smoke-exposed mice. Similar to clinical reports on human smokers, an enrichment of potentially pathogenic bacterial genera such as Fusobacterium, Gemella, and Neisseria was observed. Our findings suggest that cigarette smoke exposure predisposes to pneumococcal colonization independent of changes to the nasal microbiota and that microbiota dysbiosis observed in smokers may occur as a consequence of established pathogen colonization. PMID:28760931

Streptococcus pneumoniae Colonization Is Required To Alter the Nasal Microbiota in Cigarette Smoke-Exposed Mice.

PubMed

Shen, Pamela; Whelan, Fiona J; Schenck, L Patrick; McGrath, Joshua J C; Vanderstocken, Gilles; Bowdish, Dawn M E; Surette, Michael G; Stämpfli, Martin R

2017-10-01

Smokers have nasal microbiota dysbiosis, with an increased frequency of colonizing bacterial pathogens. It is possible that cigarette smoke increases pathogen acquisition by perturbing the microbiota and decreasing colonization resistance. However, it is difficult to disentangle microbiota dysbiosis due to cigarette smoke exposure from microbiota changes caused by increased pathogen acquisition in human smokers. Using an experimental mouse model, we investigated the impact of cigarette smoke on the nasal microbiota in the absence and presence of nasal pneumococcal colonization. We observed that cigarette smoke exposure alone did not alter the nasal microbiota composition. The microbiota composition was also unchanged at 12 h following low-dose nasal pneumococcal inoculation, suggesting that the ability of the microbiota to resist initial nasal pneumococcal acquisition was not impaired in smoke-exposed mice. However, nasal microbiota dysbiosis occurred as a consequence of established high-dose nasal pneumococcal colonization at day 3 in smoke-exposed mice. Similar to clinical reports on human smokers, an enrichment of potentially pathogenic bacterial genera such as Fusobacterium , Gemella , and Neisseria was observed. Our findings suggest that cigarette smoke exposure predisposes to pneumococcal colonization independent of changes to the nasal microbiota and that microbiota dysbiosis observed in smokers may occur as a consequence of established pathogen colonization. Copyright © 2017 American Society for Microbiology.

Pathogenic bacteria induce colonic PepT1 expression: an implication in host defense response

PubMed Central

Nguyen, Hang Thi Thu; Dalmasso, Guillaume; Powell, Kimberly R.; Yan, Yutao; Bhatt, Shantanu; Kalman, Daniel; Sitaraman, Shanthi; Merlin, Didier

2009-01-01

Background & Aims Expression of the di/tripeptide transporter PepT1 has been observed in the colon under inflammatory conditions, however, the inducing factors and underlying mechanisms remain unknown. Here, we address the effects of pathogenic bacteria on colonic PepT1 expression together with its functional consequences. Methods Human colonic HT29-Cl.19A cells were infected with the attaching and effacing (A/E) enteropathogenic E. coli (EPEC). Wild-type and PepT1 transgenic mice or cultured colonic tissues derived from these mice were infected with Citrobacter rodentium, a murine A/E pathogen related to EPEC. Results EPEC induced PepT1 expression and activity in HT29-Cl.19A cells by intimately attaching to host cells through lipid rafts. Induction of PepT1 expression by EPEC required the transcription factor Cdx2. PepT1 expression reduced binding of EPEC to lipid rafts, as well as activation of NF-κB and MAP kinase and production of IL-8. Accordingly, ex vivo and in vivo experiments revealed that C. rodentium induced colonic PepT1 expression and that, compared to their wild-type counterparts, PepT1 transgenic mice infected with C. rodentium exhibited decreased bacterial colonization, production of pro-inflammatory cytokines, and neutrophil infiltration into the colon. Conclusions Our findings demonstrate a molecular mechanism underlying the regulation of colonic PepT1 expression under pathological conditions and reveal a novel role for PepT1 in host defense via its capacity to modulate bacterial-epithelial interactions and intestinal inflammation. PMID:19549526

Microbial colonization of basaltic glasses in hydrothermal organic-rich sediments at Guaymas Basin

PubMed Central

Callac, Nolwenn; Rommevaux-Jestin, Céline; Rouxel, Olivier; Lesongeur, Françoise; Liorzou, Céline; Bollinger, Claire; Ferrant, Antony; Godfroy, Anne

2013-01-01

Oceanic basalts host diverse microbial communities with various metabolisms involved in C, N, S, and Fe biogeochemical cycles which may contribute to mineral and glass alteration processes at, and below the seafloor. In order to study the microbial colonization on basaltic glasses and their potential biotic/abiotic weathering products, two colonization modules called AISICS (“Autonomous in situ Instrumented Colonization System”) were deployed in hydrothermal deep-sea sediments at the Guaymas Basin for 8 days and 22 days. Each AISICS module contained 18 colonizers (including sterile controls) filled with basaltic glasses of contrasting composition. Chemical analyses of ambient fluids sampled through the colonizers showed a greater contribution of hydrothermal fluids (maximum temperature 57.6°C) for the module deployed during the longer time period. For each colonizer, the phylogenetic diversity and metabolic function of bacterial and archaeal communities were explored using a molecular approach by cloning and sequencing. Results showed large microbial diversity in all colonizers. The bacterial distribution was primarily linked to the deployment duration, as well as the depth for the short deployment time module. Some 16s rRNA sequences formed a new cluster of Epsilonproteobacteria. Within the Archaea the retrieved diversity could not be linked to either duration, depth or substrata. However, mcrA gene sequences belonging to the ANME-1 mcrA-guaymas cluster were found sometimes associated with their putative sulfate-reducers syntrophs depending on the colonizers. Although no specific glass alteration texture was identified, nano-crystals of barite and pyrite were observed in close association with organic matter, suggesting a possible biological mediation. This study gives new insights into the colonization steps of volcanic rock substrates and the capability of microbial communities to exploit new environmental conditions. PMID:23986754

Live Attenuated Influenza Vaccine Enhances Colonization of Streptococcus pneumoniae and Staphylococcus aureus in Mice

PubMed Central

Mina, Michael J.; McCullers, Jonathan A.; Klugman, Keith P.

2014-01-01

ABSTRACT Community interactions at mucosal surfaces between viruses, like influenza virus, and respiratory bacterial pathogens are important contributors toward pathogenesis of bacterial disease. What has not been considered is the natural extension of these interactions to live attenuated immunizations, and in particular, live attenuated influenza vaccines (LAIVs). Using a mouse-adapted LAIV against influenza A (H3N2) virus carrying the same mutations as the human FluMist vaccine, we find that LAIV vaccination reverses normal bacterial clearance from the nasopharynx and significantly increases bacterial carriage densities of the clinically important bacterial pathogens Streptococcus pneumoniae (serotypes 19F and 7F) and Staphylococcus aureus (strains Newman and Wright) within the upper respiratory tract of mice. Vaccination with LAIV also resulted in 2- to 5-fold increases in mean durations of bacterial carriage. Furthermore, we show that the increases in carriage density and duration were nearly identical in all aspects to changes in bacterial colonizing dynamics following infection with wild-type (WT) influenza virus. Importantly, LAIV, unlike WT influenza viruses, had no effect on severe bacterial disease or mortality within the lower respiratory tract. Our findings are, to the best of our knowledge, the first to demonstrate that vaccination with a live attenuated viral vaccine can directly modulate colonizing dynamics of important and unrelated human bacterial pathogens, and does so in a manner highly analogous to that seen following wild-type virus infection. PMID:24549845

Schwannoma of the sigmoid colon

PubMed Central

Çakır, Tuğrul; Aslaner, Arif; Yaz, Müjgan; Gündüz, Umut rıza

2015-01-01

Colonic schwannomas are very rare gastrointestinal tumours originating from Schwann cells, which form the neural sheath. Primary schwannomas of the lower gastrointestinal tract are very rare and usually benign in nature. However, if they are not surgically removed, malign degeneration can occur. We report a case of a 79-year-old woman who presented to our clinic with rectal bleeding and constipation. She underwent a lower gastrointestinal tract endoscopy. A mass subtotally obstructing the lumen of the sigmoid colon was seen and biopsies were taken. Histopathological examination indicated a suspicion of gastrointestinal tumour and the patient underwent sigmoid colon resection after preoperative evaluation by laboratory analysis, abdominal ultrasonography and CT. Her postoperative course was uneventful and she was discharged on the fifth day for outpatient control. The histopathology report revealed schwannoma of the sigmoid colon. This was a case of schwannoma of the sigmoid colon that was successfully treated with total resection. PMID:25976197

The primary case is not enough: Variation among individuals, groups and social networks modify bacterial transmission dynamics.

PubMed

Keiser, Carl N; Pinter-Wollman, Noa; Ziemba, Michael J; Kothamasu, Krishna S; Pruitt, Jonathan N

2018-03-01

The traits of the primary case of an infectious disease outbreak, and the circumstances for their aetiology, potentially influence the trajectory of transmission dynamics. However, these dynamics likely also depend on the traits of the individuals with whom the primary case interacts. We used the social spider Stegodyphus dumicola to test how the traits of the primary case, group phenotypic composition and group size interact to facilitate the transmission of a GFP-labelled cuticular bacterium. We also compared bacterial transmission across experimentally generated "daisy-chain" vs. "star" networks of social interactions. Finally, we compared social network structure across groups of different sizes. Groups of 10 spiders experienced more bacterial transmission events compared to groups of 30 spiders, regardless of groups' behavioural composition. Groups containing only one bold spider experienced the lowest levels of bacterial transmission regardless of group size. We found no evidence for the traits of the primary case influencing any transmission dynamics. In a second experiment, bacteria were transmitted to more individuals in experimentally induced star networks than in daisy-chains, on which transmission never exceeded three steps. In both experimental network types, transmission success depended jointly on the behavioural traits of the interacting individuals; however, the behavioural traits of the primary case were only important for transmission on star networks. Larger social groups exhibited lower interaction density (i.e. had a low ratio of observed to possible connections) and were more modular, i.e. they had more connections between nodes within a subgroup and fewer connections across subgroups. Thus, larger groups may restrict transmission by forming fewer interactions and by isolating subgroups that interacted with the primary case. These findings suggest that accounting for the traits of single exposed hosts has less power in predicting transmission

Biofilm is a Major Virulence Determinant in Bacterial Colonization of Chronic Skin Ulcers Independently from the Multidrug Resistant Phenotype

PubMed Central

Di Domenico, Enea Gino; Farulla, Ilaria; Prignano, Grazia; Gallo, Maria Teresa; Vespaziani, Matteo; Cavallo, Ilaria; Sperduti, Isabella; Pontone, Martina; Bordignon, Valentina; Cilli, Laura; De Santis, Alessandra; Di Salvo, Fabiola; Pimpinelli, Fulvia; Lesnoni La Parola, Ilaria; Toma, Luigi; Ensoli, Fabrizio

2017-01-01

Bacterial biofilm is a major factor in delayed wound healing and high levels of biofilm production have been repeatedly described in multidrug resistant organisms (MDROs). Nevertheless, a quantitative correlation between biofilm production and the profile of antimicrobial drug resistance in delayed wound healing remains to be determined. Microbial identification, antibiotic susceptibility and biofilm production were assessed in 135 clinical isolates from 87 patients. Gram-negative bacteria were the most represented microorganisms (60.8%) with MDROs accounting for 31.8% of the total isolates. Assessment of biofilm production revealed that 80% of the strains were able to form biofilm. A comparable level of biofilm production was found with both MDRO and not-MDRO with no significant differences between groups. All the methicillin-resistant Staphylococcus aureus (MRSA) and 80% of Pseudomonas aeruginosa MDR strains were found as moderate/high biofilm producers. Conversely, less than 17% of Klebsiella pneumoniae extended-spectrum beta-lactamase (ESBL), Escherichia coli-ESBL and Acinetobacter baumannii were moderate/high biofilm producers. Notably, those strains classified as non-biofilm producers, were always associated with biofilm producer bacteria in polymicrobial colonization. This study shows that biofilm producers were present in all chronic skin ulcers, suggesting that biofilm represents a key virulence determinant in promoting bacterial persistence and chronicity of ulcerative lesions independently from the MDRO phenotype. PMID:28513576

A High Grain Diet Dynamically Shifted the Composition of Mucosa-Associated Microbiota and Induced Mucosal Injuries in the Colon of Sheep.

PubMed

Wang, Yue; Xu, Lei; Liu, Junhua; Zhu, Weiyun; Mao, Shengyong

2017-01-01

This study investigated the dynamic shifts in mucosa-associated microbiota composition and mucosal morphology in the colon of sheep fed a high grain (HG) diet. A total of 20 male sheep were randomly assigned to four groups ( n = 5 for each). The sheep in first group received hay diet. The animals in other 3 groups were fed an HG diet for 7 (HG7), 14 (HG14), or 28 (HG28) days, respectively. Colonic digesta samples were collected to determine the pH and the concentrations of volatile fatty acid (VFA) and lactate. The colonic mucosa was sampled to characterize the bacterial communities using Illumina MiSeq sequencing and to determine mRNA expression levels of cytokines and tight junction protein genes using quantitative real-time PCR. As time advanced, results revealed that colonic pH linearly decreased ( P = 0.007), and the concentrations of total VFA linearly increased ( P < 0.001). Microbial analysis showed that an HG diet linearly reduced ( P < 0.050) the diversity and richness of the colonic microbiota. The principal coordinate analysis results showed that the colonic mucosa-associated bacterial communities of the four groups significantly shifted with number of days fed an HG diet. At the genus level, HG feeding significantly increased the relative abundance of some taxa including Prevotella , Coprococcus , Roseburia , and Clostridium_sensu_stricto_1 , and decreased the proportion of Treponema, and the percentage of these taxa was not affected by days fed an HG diet. The microscopic examination showed that HG feeding caused the mucosal epithelial injury. The RT-PCR results showed that the mRNA expression of claudin-1 ( P = 0.038), IL-1β ( P = 0.045), IL-6 ( P = 0.050), and TNF-α ( P = 0.020) increased linearly with number of days fed an HG diet. The correlation analysis revealed significant correlation between the colonic mucosal mRNA expression of cytokines and mucosal bacterial composition. Generally, HG feeding increased colonic fermentation and altered

A High Grain Diet Dynamically Shifted the Composition of Mucosa-Associated Microbiota and Induced Mucosal Injuries in the Colon of Sheep

PubMed Central

Wang, Yue; Xu, Lei; Liu, Junhua; Zhu, Weiyun; Mao, Shengyong

2017-01-01

This study investigated the dynamic shifts in mucosa-associated microbiota composition and mucosal morphology in the colon of sheep fed a high grain (HG) diet. A total of 20 male sheep were randomly assigned to four groups (n = 5 for each). The sheep in first group received hay diet. The animals in other 3 groups were fed an HG diet for 7 (HG7), 14 (HG14), or 28 (HG28) days, respectively. Colonic digesta samples were collected to determine the pH and the concentrations of volatile fatty acid (VFA) and lactate. The colonic mucosa was sampled to characterize the bacterial communities using Illumina MiSeq sequencing and to determine mRNA expression levels of cytokines and tight junction protein genes using quantitative real-time PCR. As time advanced, results revealed that colonic pH linearly decreased (P = 0.007), and the concentrations of total VFA linearly increased (P < 0.001). Microbial analysis showed that an HG diet linearly reduced (P < 0.050) the diversity and richness of the colonic microbiota. The principal coordinate analysis results showed that the colonic mucosa-associated bacterial communities of the four groups significantly shifted with number of days fed an HG diet. At the genus level, HG feeding significantly increased the relative abundance of some taxa including Prevotella, Coprococcus, Roseburia, and Clostridium_sensu_stricto_1, and decreased the proportion of Treponema, and the percentage of these taxa was not affected by days fed an HG diet. The microscopic examination showed that HG feeding caused the mucosal epithelial injury. The RT-PCR results showed that the mRNA expression of claudin-1 (P = 0.038), IL-1β (P = 0.045), IL-6 (P = 0.050), and TNF-α (P = 0.020) increased linearly with number of days fed an HG diet. The correlation analysis revealed significant correlation between the colonic mucosal mRNA expression of cytokines and mucosal bacterial composition. Generally, HG feeding increased colonic fermentation and altered colonic mucosal

Surveyed opinion of American trauma surgeons in management of colon injuries.

PubMed

Eshraghi, N; Mullins, R J; Mayberry, J C; Brand, D M; Crass, R A; Trunkey, D D

1998-01-01

Primary repair or resection and anastomosis of colon wounds have been advocated in many recent studies, but the proportion of trauma surgeons accepting these recommendations is unknown. To determine the current preferences of American trauma surgeons for colon injury management. Four hundred forty-nine members of the American Association for the Surgery of Trauma were surveyed regarding their preferred management of eight types of colon wounds among three options: diverting colostomy (DC), primary repair (PR), or resection and anastomosis (RA). The influence of selected patient factors and surgeons' characteristics on the choice of management was also surveyed. Seventy-three percent of surgeons completed the survey. Ninety-eight percent chose PR for at least one type of injury. Thirty percent never selected DC. High-velocity gunshot wound was the only injury for which the majority (54%) would perform DC. More than 55% of the surgeons favored RA when the isolated colon injury was a contusion with possible devascularization, laceration greater than 50% of the diameter, or transection. Surgeons who managed five or fewer colon wounds per year chose DC more frequently (p < 0.001) and PR less frequently (p < 0.001) than surgeons who managed six or more colon wounds per year. The prevailing opinion of trauma surgeons favors primary repair or resection of colon injuries, including anastomosis of unprepared bowel. Surgeons who manage fewer colon wounds prefer colostomy more frequently.

Plant growth-promoting bacterial endophytes.

PubMed

Santoyo, Gustavo; Moreno-Hagelsieb, Gabriel; Orozco-Mosqueda, Ma del Carmen; Glick, Bernard R

2016-02-01

Bacterial endophytes ubiquitously colonize the internal tissues of plants, being found in nearly every plant worldwide. Some endophytes are able to promote the growth of plants. For those strains the mechanisms of plant growth-promotion known to be employed by bacterial endophytes are similar to the mechanisms used by rhizospheric bacteria, e.g., the acquisition of resources needed for plant growth and modulation of plant growth and development. Similar to rhizospheric plant growth-promoting bacteria, endophytic plant growth-promoting bacteria can act to facilitate plant growth in agriculture, horticulture and silviculture as well as in strategies for environmental cleanup (i.e., phytoremediation). Genome comparisons between bacterial endophytes and the genomes of rhizospheric plant growth-promoting bacteria are starting to unveil potential genetic factors involved in an endophytic lifestyle, which should facilitate a better understanding of the functioning of bacterial endophytes. Copyright © 2015 Elsevier GmbH. All rights reserved.

The Vibrio cholerae Colonization Factor GbpA Possesses a Modular Structure that Governs Binding to Different Host Surfaces

PubMed Central

Wong, Edmond; Vaaje-Kolstad, Gustav; Ghosh, Avishek; Hurtado-Guerrero, Ramon; Konarev, Peter V.; Ibrahim, Adel F. M.; Svergun, Dmitri I.; Eijsink, Vincent G. H.; Chatterjee, Nabendu S.; van Aalten, Daan M. F.

2012-01-01

Vibrio cholerae is a bacterial pathogen that colonizes the chitinous exoskeleton of zooplankton as well as the human gastrointestinal tract. Colonization of these different niches involves an N-acetylglucosamine binding protein (GbpA) that has been reported to mediate bacterial attachment to both marine chitin and mammalian intestinal mucin through an unknown molecular mechanism. We report structural studies that reveal that GbpA possesses an unusual, elongated, four-domain structure, with domains 1 and 4 showing structural homology to chitin binding domains. A glycan screen revealed that GbpA binds to GlcNAc oligosaccharides. Structure-guided GbpA truncation mutants show that domains 1 and 4 of GbpA interact with chitin in vitro, whereas in vivo complementation studies reveal that domain 1 is also crucial for mucin binding and intestinal colonization. Bacterial binding studies show that domains 2 and 3 bind to the V. cholerae surface. Finally, mouse virulence assays show that only the first three domains of GbpA are required for colonization. These results explain how GbpA provides structural/functional modular interactions between V. cholerae, intestinal epithelium and chitinous exoskeletons. PMID:22253590

Green kiwifruit modulates the colonic microbiota in growing pigs.

PubMed

Han, K S; Balan, P; Molist Gasa, F; Boland, M

2011-04-01

To investigate whether green kiwifruit modulates the composition of colonic microbiota in growing pigs. Thirty-two pigs were fed the control diet or one of the three test diets containing either cellulose, freeze-dried kiwifruit or kiwifruit fibre as the sole fibre source for 14-day study. A Ward's dendrogram of similarity cluster analysis on PCR-DGGE gels revealed that inclusion of freeze-dried kiwifruit and kiwifruit fibre into diets altered the bacterial community, indicating the presence of two distinct clusters. Quantification of different bacterial groups by qPCR demonstrated that pigs fed the freeze-dried kiwifruit or kiwifruit fibre diets had a significantly higher number (P < 0·05) of total bacteria and Bacteroides group and a lower number of Enterobacteria and Escherichia coli group, as well as a greater ratio of Lactobacillus to Enterobacteria when compared to pigs fed the control or cellulose diets. Green kiwifruit, mainly because of fibre, modulated the colonic microbiota, leading to an improved intestinal environment in growing pigs. This is the first report regarding the effect of green kiwifruit on gut microbiota using the in vivo pig model. These results provide the first evidence of interaction between green kiwifruit and colonic microbiota. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Mutualistic interaction between Salmonella enterica and Aspergillus niger and its effects on Zea mays colonization.

PubMed

Balbontín, Roberto; Vlamakis, Hera; Kolter, Roberto

2014-11-01

Salmonella Typhimurium inhabits a variety of environments and is able to infect a broad range of hosts. Throughout its life cycle, some hosts can act as intermediates in the path to the infection of others. Aspergillus niger is a ubiquitous fungus that can often be found in soil or associated to plants and microbial consortia. Recently, S. Typhimurium was shown to establish biofilms on the hyphae of A. niger. In this work, we have found that this interaction is stable for weeks without a noticeable negative effect on either organism. Indeed, bacterial growth is promoted upon the establishment of the interaction. Moreover, bacterial biofilms protect the fungus from external insults such as the effects of the anti-fungal agent cycloheximide. Thus, the Salmonella-Aspergillus interaction can be defined as mutualistic. A tripartite gnotobiotic system involving the bacterium, the fungus and a plant revealed that co-colonization has a greater negative effect on plant growth than colonization by either organism in dividually. Strikingly, co-colonization also causes a reduction in plant invasion by S. Typhimurium. This work demonstrates that S. Typhimurium and A. niger establish a mutualistic interaction that alters bacterial colonization of plants and affects plant physiology. © 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Percutaneous drainage of colonic diverticular abscess: is colon resection necessary?

PubMed

Gaertner, Wolfgang B; Willis, David J; Madoff, Robert D; Rothenberger, David A; Kwaan, Mary R; Belzer, George E; Melton, Genevieve B

2013-05-01

Recurrent diverticulitis has been reported in up to 30% to 40% of patients who recover from an episode of colonic diverticular abscess, so elective interval resection is traditionally recommended. The aim of this study was to review the outcomes of patients who underwent percutaneous drainage of colonic diverticular abscess without subsequent operative intervention. This was an observational study. This investigation was conducted at a tertiary care academic medical center and a single-hospital health system. Patients treated for symptomatic colonic diverticular abscess from 2002 through 2007 were included. The primary outcomes measured were complications, recurrence, and colectomy-free survival. Two hundred eighteen patients underwent percutaneous drainage of colonic diverticular abscesses. Thirty-two patients (15%) did not undergo subsequent colonic resection. Abscess location was pelvic (n = 9) and paracolic (n = 23), the mean abscess size was 4.2 cm, and the median duration of percutaneous drainage was 20 days. The comorbidities of this group of patients included severe cardiac disease (n = 16), immunodeficiency (n = 7), and severe pulmonary disease (n = 6). Freedom from recurrence at 7.4 years was 0.58 (95% CI 0.42-0.73). All recurrences were managed nonoperatively. Recurrence was significantly associated with an abscess size larger than 5 cm. Colectomy-free survival at 7.4 years was 0.17 (95% CI 0.13-0.21). This study was limited by its retrospective, nonexperimental design and short follow-up. In selected patients, observation after percutaneous drainage of colonic diverticular abscess appears to be a safe and low-risk management option.

Contribution of dinitrogen fixation to bacterial and primary productivity in the Gulf of Aqaba (Red Sea)

NASA Astrophysics Data System (ADS)

Rahav, E.; Herut, B.; Mulholland, M. R.; Voß, B.; Stazic, D.; Steglich, C.; Hess, W. R.; Berman-Frank, I.

2013-06-01

We evaluated the seasonal contribution of heterotrophic and autotrophic diazotrophy to the total dinitrogen (N2) fixation in a representative pelagic station in the northern Gulf of Aqaba in early spring when the water column was mixed and during summer under full thermal stratification. N2 fixation rates were low during the mixed period (˜ 0.1 nmol N L-1 d-1) and were significantly coupled with both primary and bacterial productivity. During the stratified period N2 fixation rates were four-fold higher (˜ 0.4 nmol N L-1 d-1) and were significantly correlated solely with bacterial productivity. Furthermore, while experimental enrichment of seawater by phosphorus (P) enhanced bacterial productivity and N2 fixation rates during both seasons primary productivity was stimulated by P only in the early spring. Metatranscriptomic analyses from the stratified period identified the major diazotrophic contributors as related to heterotrophic prokaryotes from the Euryarchaeota and Desulfobacterales (Deltaproteobacteria) or Chlorobiales (Chlorobia). Moreover, during this season, experimental amendments to seawater applying a combination of the photosynthetic inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and a mixture of amino acids increased both bacterial productivity and N2 fixation rates. Our findings from the northern Gulf of Aqaba indicate a~shift in the diazotrophic community from phototrophic and heterotrophic populations, including small blooms of the cyanobacterium Trichodesmium, in winter/early spring, to predominantly heterotrophic diazotrophs in summer that may be both P and carbon limited as the additions of P and amino acids illustrated.

Reviewing the Management of Obstructive Left Colon Cancer: Assessing the Feasibility of the One-stage Resection and Anastomosis After Intraoperative Colonic Irrigation.

PubMed

Awotar, Gavish Kumar; Guan, Guoxin; Sun, Wei; Yu, Hongliang; Zhu, Ming; Cui, Xinye; Liu, Jie; Chen, Jiaxi; Yang, Baoshun; Lin, Jianyu; Deng, Zeyong; Luo, Jianwei; Wang, Chen; Nur, Osman Abdifatah; Dhiman, Pankaj; Liu, Pixu; Luo, Fuwen

2017-06-01

The management of obstructive left colon cancer (OLCC) remains debatable with the single-stage procedure of primary colonic anastomosis after cancer resection and on-table intracolonic lavage now being supported. Patients with acute OLCC who were admitted between January 2008 and January 2015 were distributed into 5 different groups. Group ICI underwent emergency laparotomy for primary anastomosis following colonic resection and intraoperative colonic lavage; Group HP underwent emergency Hartmann's Procedure; Group CON consisted of patients treated by conservative management with subsequent elective open cancer resection; Group COL were colostomy patients; and Group INT consisted of patients who had interventional radiology followed by open elective colon cancer resection. The demographics of the patients and comorbidity, intraoperative data, and postoperative data were collected, with P < .05 as significant. There were 4 deaths in 138 cases (2.90%). There was only 1 patient who had anastomotic leakage (5.56%) in Group ICI, compared with none in Group HP and Group COL, 1 case in Group INT (7.69%), and 2 cases in Group CON (6.06%) (P > .05). Group INT and Group CON, when compared to the three surgical groups, Groups ICI, Group COL, and Group HP, individually, were statistically significant for the duration of surgery (P < .05). Primary anastomosis following colonic resection after irrigation can be safely performed in selected patients, with the necessary surgical expertise, with no increased risk in mortality, anastomotic leakage, and other postoperative complications. Copyright © 2017 Elsevier Inc. All rights reserved.

Inoculation of a phenanthrene-degrading endophytic bacterium reduces the phenanthrene level and alters the bacterial community structure in wheat.

PubMed

Liu, Juan; Xiang, Yanbing; Zhang, Zhiming; Ling, Wanting; Gao, Yanzheng

2017-06-01

Colonization by polycyclic aromatic hydrocarbon (PAH)-degrading endophytic bacteria (PAHDEB) can reduce the PAH contamination risk in plant. However, little information is available on the impact of PAHDEB colonization on the endophytic bacterial community of inner plant tissues. A phenanthrene-degrading endophytic bacterium (PDEB), Massilia sp. Pn2, was inoculated onto the roots of wheat and subjected to greenhouse container experiments. The endophytic bacterial community structure in wheat was investigated using high-throughput sequencing technology. The majority of endophytic bacteria in wheat were Proteobacteria, and the dominant genus was Pseudomonas. Phenanthrene contamination clearly increased the diversity of endophytic bacteria in wheat. The cultivable endophytic bacteria counts in wheat decreased with increasing the level of phenanthrene contamination; the endophytic bacterial community structure changed correspondingly, and the bacterial richness first increased and then decreased. Inoculation of strain Pn2 reduced the phenanthrene contamination in wheat, enlarged the biomass of wheat roots, changed the bacterial community structure and enhanced the cell counts, diversity and richness of endophytic bacteria in phenanthrene-contaminated wheat in a contamination level-dependent manner. The findings of this investigation provide insight into the responses of endophytic bacterial community in plant to external PAH contamination and PAHDEB colonization.

Revealing structure and assembly cues for Arabidopsis root-inhabiting bacterial microbiota.

PubMed

Bulgarelli, Davide; Rott, Matthias; Schlaeppi, Klaus; Ver Loren van Themaat, Emiel; Ahmadinejad, Nahal; Assenza, Federica; Rauf, Philipp; Huettel, Bruno; Reinhardt, Richard; Schmelzer, Elmon; Peplies, Joerg; Gloeckner, Frank Oliver; Amann, Rudolf; Eickhorst, Thilo; Schulze-Lefert, Paul

2012-08-02

The plant root defines the interface between a multicellular eukaryote and soil, one of the richest microbial ecosystems on Earth. Notably, soil bacteria are able to multiply inside roots as benign endophytes and modulate plant growth and development, with implications ranging from enhanced crop productivity to phytoremediation. Endophytic colonization represents an apparent paradox of plant innate immunity because plant cells can detect an array of microbe-associated molecular patterns (also known as MAMPs) to initiate immune responses to terminate microbial multiplication. Several studies attempted to describe the structure of bacterial root endophytes; however, different sampling protocols and low-resolution profiling methods make it difficult to infer general principles. Here we describe methodology to characterize and compare soil- and root-inhabiting bacterial communities, which reveals not only a function for metabolically active plant cells but also for inert cell-wall features in the selection of soil bacteria for host colonization. We show that the roots of Arabidopsis thaliana, grown in different natural soils under controlled environmental conditions, are preferentially colonized by Proteobacteria, Bacteroidetes and Actinobacteria, and each bacterial phylum is represented by a dominating class or family. Soil type defines the composition of root-inhabiting bacterial communities and host genotype determines their ribotype profiles to a limited extent. The identification of soil-type-specific members within the root-inhabiting assemblies supports our conclusion that these represent soil-derived root endophytes. Surprisingly, plant cell-wall features of other tested plant species seem to provide a sufficient cue for the assembly of approximately 40% of the Arabidopsis bacterial root-inhabiting microbiota, with a bias for Betaproteobacteria. Thus, this root sub-community may not be Arabidopsis-specific but saprophytic bacteria that would naturally be found

Plant species affect colonization patterns and metabolic activity of associated endophytes during phytoremediation of crude oil-contaminated soil.

PubMed

Fatima, K; Imran, A; Amin, I; Khan, Q M; Afzal, M

2016-04-01

Plants coupled with endophytic bacteria hold great potential for the remediation of polluted environment. The colonization patterns and activity of inoculated endophytes in rhizosphere and endosphere of host plant are among the primary factors that may influence the phytoremediation process. However, these colonization patterns and metabolic activity of the inoculated endophytes are in turn controlled by none other than the host plant itself. The present study aims to determine such an interaction specifically for plant-endophyte systems remediating crude oil-contaminated soil. A consortium (AP) of two oil-degrading endophytic bacteria (Acinetobacter sp. strain BRSI56 and Pseudomonas aeruginosa strain BRRI54) was inoculated to two grasses, Brachiaria mutica and Leptochloa fusca, vegetated in crude oil-contaminated soil. Colonization patterns and metabolic activity of the endophytes were monitored in the rhizosphere and endosphere of the plants. Bacterial augmentation enhanced plant growth and crude oil degradation. Maximum crude oil degradation (78%) was achieved with B. mutica plants inoculated with AP consortium. This degradation was significantly higher than those treatments, where plants and bacteria were used individually or L. fusca and endophytes were used in combination. Moreover, colonization and metabolic activity of the endophytes were higher in the rhizosphere and endosphere of B. mutica than L. fusca. The plant species affected not only colonization pattern and biofilm formation of the inoculated bacteria in the rhizosphere and endosphere of the host plant but also affected the expression of alkane hydroxylase gene, alkB. Hence, the investigation revealed that plant species can affect colonization patterns and metabolic activity of inoculated endophytic bacteria and ultimately the phytoremediation process.

Relationship between airway colonization, inflammation and exacerbation frequency in COPD.

PubMed

Tumkaya, Munir; Atis, Sibel; Ozge, Cengiz; Delialioglu, Nuran; Polat, Gurbuz; Kanik, Arzu

2007-04-01

To evaluate bacterial colonization and the airway inflammatory response, and its relationship to the frequency of exacerbation in patients with stable chronic obstructive pulmonary disease (COPD). Quantitative bacteriologic cultures, neutrophil elastase, myeloperoxidase (MPO), tumor necrosis factor alpha (TNF-alpha) and interleukin (IL)-8 were measured in bronchoalveoler lavage (BAL) in 39 patients with stable COPD [19 with frequent exacerbation (> or = 3/year), and 20 with infrequent] and in 18 healthy controls (10 smokers and 8 non-smokers). BAL revealed the microorganisms with potential pathogenicity above the established threshold (> or = 10(3)cfu/ml) in 68.4% of patients with frequent exacerbation, 55% of infrequent exacerbation, 40% of smokers and 12.5% of non-smokers controls (P=0.05). BAL MPO, IL-8 and TNF-alpha levels were found to be significantly higher in COPD as compared to controls (P=0.001). However, only IL-8 level was significantly higher in COPD patients with frequent exacerbation as compared to infrequent (P=0.001). Airway bacterial load correlated with levels of airway inflammation markers in COPD (P<0.05). The bacterial load and airway inflammation contributes to each other in stable COPD. However, there is a link only between interleukine (IL)-8 and frequent exacerbations. Clearly, the relationship between bacterial colonization, airway inflammation and frequent exacerbations is of major importance in understanding of the COPD pathogenesis.

[Prevalence of nasal carriage of Staphylococcus aureus and Streptococcus pneumoniae in Primary Care and factors associated with colonization].

PubMed

Boada, Albert; Almeda, Jesús; Grenzner, Elisabet; Pons-Vigués, Mariona; Morros, Rosa; Juvé, Rosa; Simonet, Pere J; den Heijer, Casper D J; Bolíbar, Bonaventura

2015-01-01

To determine (i) the prevalence of Staphylococcus aureus (S.aureus) and Streptococcus pneumoniae (S.pneumoniae) nasal carriage in Primary Health Care patients in area of Barcelona, and (ii) the factors associated with S.aureus and S.pneumoniae colonization. Multi-center cross-sectional study conducted in 2010-2011 with the participation of 27 Primary Health Care professionals. Nasopharyngeal swabs were obtained from 3,969 patients over 4 years of age who did not present with any sign of infection. S.aureus and/or S.pneumoniae carrier state. socio-demographic characteristics, health status, vaccination status, occupation, and living with children. A descriptive analysis was performed. The prevalence of carriers of S.aureus and/or S.pneumoniae was calculated and logistic regression models were adjusted by age. In children from 4 to 14 years old, the prevalence of S.aureus carriers was 35.7%, of S.pneumoniae 27.1%, and 5.8% were co-colonized. In adults older than 14 years old, the prevalence was 17.8%, 3.5%, and 0.5%, respectively. In children, S.aureus carrier state was inversely associated with S.pneumoniae carrier state; S.pneumoniae was associated with younger age, and inversely associated with S.aureus carrier state. In adults, being a carrier of S.aureus was associated with male gender, younger age, and a health-related occupation, whereas S.pneumoniae carrier state was associated with living with children under 6 years of age. The proportion of co-colonized carriers was low (1.0%). The proportion of S.aureus and S.pneumoniae carriers was higher in children than in adults. Age was the only factor associated with healthy carrier status for S.aureus and for S.pneumoniae. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

The use of PCR/Electrospray Ionization-Time-of-Flight-Mass Spectrometry (PCR/ESI-TOF-MS) to detect bacterial and fungal colonization in healthy military service members.

PubMed

Vetor, Ryan; Murray, Clinton K; Mende, Katrin; Melton-Kreft, Rachel; Akers, Kevin S; Wenke, Joseph; Spirk, Tracy; Guymon, Charles; Zera, Wendy; Beckius, Miriam L; Schnaubelt, Elizabeth R; Ehrlich, Garth; Vento, Todd J

2016-07-22

The role of microbial colonization in disease is complex. Novel molecular tools to detect colonization offer theoretical improvements over traditional methods. We evaluated PCR/Electrospray Ionization-Time-of-Flight-Mass Spectrometry (PCR/ESI-TOF-MS) as a screening tool to study colonization of healthy military service members. We assessed 101 healthy Soldiers using PCR/ESI-TOF-MS on nares, oropharynx, and groin specimens for the presence of gram-positive and gram-negative bacteria (GNB), fungi, and antibiotic resistance genes. A second set of swabs was processed by traditional culture, followed by identification using the BD Phoenix automated system; comparison between PCR/ESI-TOF-MS and culture was carried out only for GNB. Using PCR/ESI-TOF-MS, at least one colonizing organism was found on each individual: mean (SD) number of organisms per subject of 11.8(2.8). The mean number of organisms in the nares, groin and oropharynx was 3.8(1.3), 3.8(1.4) and 4.2(2), respectively. The most commonly detected organisms were aerobic gram-positive bacteria: primarily coagulase-negative Staphylococcus (101 subjects: 341 organisms), Streptococcus pneumoniae (54 subjects: 57 organisms), Staphylococcus aureus (58 subjects: 80 organisms) and Nocardia asteroides (45 subjects: 50 organisms). The mecA gene was found in 96 subjects. The most commonly found GNB was Haemophilus influenzae (20 subjects: 21 organisms) and the most common anaerobe was Propionibacterium acnes (59 subjects). Saccharomyces species (30 subjects) were the most common fungi detected. Only one GNB (nares E. coli) was identified in the same subject by both diagnostic systems. PCR/ESI-TOF-MS detected common colonizing organisms and identified more typically-virulent bacteria in asymptomatic, healthy adults. PCR/ESI-TOF-MS appears to be a useful method for detecting bacterial and fungal organisms, but further clinical correlation and validation studies are needed.

Bloom and bust: intestinal microbiota dynamics in response to hospital exposures and Clostridium difficile colonization or infection.

PubMed

Vincent, Caroline; Miller, Mark A; Edens, Thaddeus J; Mehrotra, Sudeep; Dewar, Ken; Manges, Amee R

2016-03-14

Clostridium difficile infection (CDI) is the leading infectious cause of nosocomial diarrhea. Hospitalized patients are at increased risk of developing CDI because they are exposed to C. difficile spores through contact with the hospital environment and often receive antibiotics and other medications that can disrupt the integrity of the indigenous intestinal microbiota and impair colonization resistance. Using whole metagenome shotgun sequencing, we examined the diversity and composition of the fecal microbiota in a prospective cohort study of 98 hospitalized patients. Four patients had asymptomatic C. difficile colonization, and four patients developed CDI. We observed dramatic shifts in the structure of the gut microbiota during hospitalization. In contrast to CDI cases, asymptomatic patients exhibited elevated relative abundance of potentially protective bacterial taxa in their gut at the onset of C. difficile colonization. Use of laxatives was associated with significant reductions in the relative abundance of Clostridium and Eubacterium; species within these genera have previously been shown to enhance resistance to CDI via the production of secondary bile acids. Cephalosporin and fluoroquinolone exposure decreased the frequency of Clostridiales Family XI Incertae Sedis, a bacterial family that has been previously associated with decreased CDI risk. This study underscores the detrimental impact of antibiotics as well as other medications, particularly laxatives, on the intestinal microbiota and suggests that co-colonization with key bacterial taxa may prevent C. difficile overgrowth or the transition from asymptomatic C. difficile colonization to CDI.

Candida albicans and bacterial microbiota interactions in the cecum during recolonization following broad-spectrum antibiotic therapy.

PubMed

Mason, Katie L; Erb Downward, John R; Mason, Kelly D; Falkowski, Nicole R; Eaton, Kathryn A; Kao, John Y; Young, Vincent B; Huffnagle, Gary B

2012-10-01

Candida albicans is a normal member of the gastrointestinal (GI) tract microbiota of healthy humans, but during host immunosuppression or alterations in the bacterial microbiota, C. albicans can disseminate and cause life-threatening illness. The bacterial microbiome of the GI tract, including lactic acid bacteria (LAB), plays a vital role in preventing fungal invasion. However, little is known about the role of C. albicans in shaping the bacterial microbiota during antibiotic recovery. We investigated the fungal burdens in the GI tracts of germfree mice and mice with a disturbed microbiome to demonstrate the role of the microbiota in preventing C. albicans colonization. Histological analysis demonstrated that colonization with C. albicans during antibiotic treatment does not trigger overt inflammation in the murine cecum. Bacterial diversity is reduced long term following cefoperazone treatment, but the presence of C. albicans during antibiotic recovery promoted the recovery of bacterial diversity. Cefoperazone diminishes Bacteroidetes populations long term in the ceca of mice, but the presence of C. albicans during cefoperazone recovery promoted Bacteroidetes population recovery. However, the presence of C. albicans resulted in a long-term reduction in Lactobacillus spp. and promoted Enterococcus faecalis populations. Previous studies have focused on the ability of bacteria to alter C. albicans; this study addresses the ability of C. albicans to alter the bacterial microbiota during nonpathogenic colonization.

The tad locus: postcards from the widespread colonization island.

PubMed

Tomich, Mladen; Planet, Paul J; Figurski, David H

2007-05-01

The Tad (tight adherence) macromolecular transport system, which is present in many bacterial and archaeal species, represents an ancient and major new subtype of type II secretion. The tad genes are present on a genomic island named the widespread colonization island (WCI), and encode the machinery that is required for the assembly of adhesive Flp (fimbrial low-molecular-weight protein) pili. The tad genes are essential for biofilm formation, colonization and pathogenesis in the genera Aggregatibacter (Actinobacillus), Haemophilus, Pasteurella, Pseudomonas, Yersinia, Caulobacter and perhaps others. Here we review the structure, function and evolution of the Tad secretion system.

Bacterial colonization stimulates a complex physiological response in the immature human intestinal epithelium

PubMed Central

Hill, David R; Huang, Sha; Nagy, Melinda S; Yadagiri, Veda K; Fields, Courtney; Mukherjee, Dishari; Bons, Brooke; Dedhia, Priya H; Chin, Alana M; Tsai, Yu-Hwai; Thodla, Shrikar; Schmidt, Thomas M; Walk, Seth

2017-01-01

The human gastrointestinal tract is immature at birth, yet must adapt to dramatic changes such as oral nutrition and microbial colonization. The confluence of these factors can lead to severe inflammatory disease in premature infants; however, investigating complex environment-host interactions is difficult due to limited access to immature human tissue. Here, we demonstrate that the epithelium of human pluripotent stem-cell-derived human intestinal organoids is globally similar to the immature human epithelium and we utilize HIOs to investigate complex host-microbe interactions in this naive epithelium. Our findings demonstrate that the immature epithelium is intrinsically capable of establishing a stable host-microbe symbiosis. Microbial colonization leads to complex contact and hypoxia driven responses resulting in increased antimicrobial peptide production, maturation of the mucus layer, and improved barrier function. These studies lay the groundwork for an improved mechanistic understanding of how colonization influences development of the immature human intestine. PMID:29110754

Bacterial colonization of the implant-abutment interface of conical connection with an internal octagon: an in vitro study using real-time PCR.

PubMed

Baj, A; Beltramini, G A; Bolzoni, A; Cura, F; Palmieri, A; Scarano, A; Ottria, L; Giannì, A B

2017-01-01

Bacterial leakage at the implant-abutment connection of a two-piece implant system is considered the main cause of peri-implantitis. Prevention of bacterial leakage at the implant-abutment connection is mandatory for reducing inflammation process around implant neck and achieving bone stability. Micro-cavities at implant-abutment connection level can favour bacterial leakage, even in modern two-piece implant systems. The conical connection with an internal octagon (CCIO) is considered to be more stable mechanically and allows a more tight link between implant and abutment. As P. gingivalis and T. forsythia penetration might have clinical relevance, it was the purpose of this investigation to evaluate molecular leakage of these two bacteria in a new two-implant system with an internal conical implant-abutment connection with internal octagon (Shiner XT, FMD Falappa Medical Devices S.p.A. Rome, Italy). To verify the ability of the implant in protecting the internal space from the external environment, the passage of genetically modified Escherichia c oli across implant-abutment interface was evaluated. Four Shiner XT implants (FMD, Falappa Medical Devices®, Rome, Italy) were immerged in a bacterial culture for 24 h and bacteria amount was measured inside implant-abutment interface with Real-time PCR. Bacteria were detected inside all studied implants, with a median percentage of 6% for P. gingivalis and 5% for T. forsythia. Other comparable studies about the tightness of the tested implant system reported similar results. The gap size at the implant-abutment connection of CCIOs was measured by other authors discovering a gap size of 1–2μm of the AstraTech system and of 4μm for the Ankylos system. Bacterial leakage along implant-abutment connection of cylindrical and tapered implants, Shiner XT, (FMD Falappa Medical Devices S.p.A. Rome, Italy) showed better results compared to other implants. Additional studies are needed to explore the relationship in terms of

Genomic analysis reveals the major driving forces of bacterial life in the rhizosphere

PubMed Central

Matilla, Miguel A; Espinosa-Urgel, Manuel; Rodríguez-Herva, José J; Ramos, Juan L; Ramos-González, María Isabel

2007-01-01

Background Mutualistic interactions less well known than those between rhizobia and legumes are commonly found between plants and bacteria, frequently pseudomonads, which colonize roots and adjacent soil areas (the rhizosphere). Results A global analysis of Pseudomonas putida genes expressed during their interaction with maize roots revealed how a bacterial population adjusts its genetic program to this lifestyle. Differentially expressed genes were identified by comparing rhizosphere-colonizing populations with three distinct controls covering a variety of nutrients, growth phases and life styles (planktonic and sessile). Ninety rhizosphere up-regulated (rup) genes, which were induced relative to all three controls, were identified, whereas there was no repressed gene in common between the experiments. Genes involved in amino acid uptake and metabolism of aromatic compounds were preferentially expressed in the rhizosphere, which reflects the availability of particular nutrients in root exudates. The induction of efflux pumps and enzymes for glutathione metabolism indicates that adaptation to adverse conditions and stress (oxidative) response are crucial for bacterial life in this environment. The finding of a GGDEF/EAL domain response regulator among the induced genes suggests a role for the turnover of the secondary messenger c-diGMP in root colonization. Several mutants in rup genes showed reduced fitness in competitive root colonization. Conclusion Our results show the importance of two selective forces of different nature to colonize the rhizosphere: stress adaptation and availability of particular nutrients. We also identify new traits conferring bacterial survival in this niche and open a way to the characterization of specific signalling and regulatory processes governing the plant-Pseudomonas association. PMID:17784941

Prospective study of vaginal bacterial flora and other risk factors for vulvovaginal candidiasis.

PubMed

McClelland, R Scott; Richardson, Barbra A; Hassan, Wisal M; Graham, Susan M; Kiarie, James; Baeten, Jared M; Mandaliya, Kishorchandra; Jaoko, Walter; Ndinya-Achola, Jeckoniah O; Holmes, King K

2009-06-15

It has been suggested that vaginal colonization with lactobacilli may reduce the risk of vulvovaginal candidiasis (VVC), but supporting data are limited. Our objective was to determine the relationship between vaginal bacterial flora and VVC. We conducted a prospective cohort analysis that involved 151 Kenyan sex workers. At monthly follow-up visits, VVC was defined as the presence of yeast buds, pseudohyphae, or both on a wet preparation (including potassium hydroxide preparation) of vaginal secretions. Generalized estimating equations were used to identify correlates of VVC. Participants returned for a median of 12 visits (interquartile range, 11-12 visits). VVC was identified at 162 visits, including 26 involving symptomatic VVC. Bacterial vaginosis was associated with fewer episodes of VVC (adjusted odds ratio [aOR], 0.29 [95% confidence interval {CI}, 0.16-0.50]). After excluding women with concurrent bacterial vaginosis, another possible cause of vaginal symptoms, the likelihood of symptomatic VVC was higher among those who had had yeast identified on wet preparation of vaginal secretions during the past 60 days (aOR, 4.06 [95% CI, 1.12-14.74]) and those with concurrent vaginal Lactobacillus colonization (aOR, 3.75 [95% CI, 1.30-10.83]). Contrary to the commonly posited hypothesis that vaginal Lactobacillus colonization has a protective effect, we found that such colonization was associated with a nearly 4-fold increase in the likelihood of symptomatic VVC.

Optimisation of isolation of richly pure and homogeneous primary human colonic smooth muscle cells.

PubMed

Tattoli, I; Corleto, V D; Taffuri, M; Campanini, N; Rindi, G; Caprilli, R; Delle Fave, G; Severi, C

2004-11-01

Inherent properties of gastrointestinal smooth muscle can be assessed using isolated cell suspensions. Currently available isolation techniques, based on short 2-h enzymatic digestion, however, present the disadvantage of low cellular yield with brief viability. These features are an important limiting factor especially in studies in humans in which tissue may not be available daily and mixing of samples is not recommended. To optimise the isolation procedure of cells from human colon to obtain a richly pure primary smooth muscle cell preparation. Slices of circular muscle layer, obtained from surgical specimens of human colon, were incubated overnight in Dulbecco's modified eagle's medium supplemented with antibiotics, foetal bovine serum, an ATP-regenerating system and collagenase. On the following day, digested muscle strips were suspended in HEPES buffer, and spontaneously dissociated smooth muscle cells were harvested and used either immediately or maintained in suspension for up to 72 h. Cell yield, purity, viability, contractile responses, associated intracellular calcium signals and RNA and protein extraction were evaluated and compared to cell suspensions obtained with the current short digestion protocol. The overnight isolation protocol offers the advantage of obtaining a pure, homogeneous, long-life viable cell suspension that maintains a fully differentiated smooth muscle phenotype unchanged for at least 72 h and that allows multiple functional/biochemical studies and efficient RNA extraction from a single human specimen.

Step-wise loss of bacterial flagellar torsion confers progressive phagocytic evasion.

PubMed

Lovewell, Rustin R; Collins, Ryan M; Acker, Julie L; O'Toole, George A; Wargo, Matthew J; Berwin, Brent

2011-09-01

Phagocytosis of bacteria by innate immune cells is a primary method of bacterial clearance during infection. However, the mechanisms by which the host cell recognizes bacteria and consequentially initiates phagocytosis are largely unclear. Previous studies of the bacterium Pseudomonas aeruginosa have indicated that bacterial flagella and flagellar motility play an important role in colonization of the host and, importantly, that loss of flagellar motility enables phagocytic evasion. Here we use molecular, cellular, and genetic methods to provide the first formal evidence that phagocytic cells recognize bacterial motility rather than flagella and initiate phagocytosis in response to this motility. We demonstrate that deletion of genes coding for the flagellar stator complex, which results in non-swimming bacteria that retain an initial flagellar structure, confers resistance to phagocytic binding and ingestion in several species of the gamma proteobacterial group of Gram-negative bacteria, indicative of a shared strategy for phagocytic evasion. Furthermore, we show for the first time that susceptibility to phagocytosis in swimming bacteria is proportional to mot gene function and, consequently, flagellar rotation since complementary genetically- and biochemically-modulated incremental decreases in flagellar motility result in corresponding and proportional phagocytic evasion. These findings identify that phagocytic cells respond to flagellar movement, which represents a novel mechanism for non-opsonized phagocytic recognition of pathogenic bacteria.

Carotenoids and colon cancer.

PubMed

Slattery, M L; Benson, J; Curtin, K; Ma, K N; Schaeffer, D; Potter, J D

2000-02-01

Carotenoids have numerous biological properties that may underpin a role for them as chemopreventive agents. However, except for beta-carotene, little is known about how dietary carotenoids are associated with common cancers, including colon cancer. The objective of this study was to evaluate associations between dietary alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin and the risk of colon cancer. Data were collected from 1993 case subjects with first primary incident adenocarcinoma of the colon and from 2410 population-based control subjects. Dietary data were collected from a detailed diet-history questionnaire and nutrient values for dietary carotenoids were obtained from the US Department of Agriculture-Nutrition Coordinating Center carotenoid database (1998 updated version). Lutein was inversely associated with colon cancer in both men and women [odds ratio (OR) for upper quintile of intake relative to lowest quintile of intake: 0.83; 95% CI: 0.66, 1.04; P = 0.04 for linear trend]. The greatest inverse association was observed among subjects in whom colon cancer was diagnosed when they were young (OR: 0.66; 95% CI: 0.48, 0.92; P = 0.02 for linear trend) and among those with tumors located in the proximal segment of the colon (OR: 0.65; 95% CI: 0.51, 0.91; P < 0.01 for linear trend). The associations with other carotenoids were unremarkable. The major dietary sources of lutein in subjects with colon cancer and in control subjects were spinach, broccoli, lettuce, tomatoes, oranges and orange juice, carrots, celery, and greens. These data suggest that incorporating these foods into the diet may help reduce the risk of developing colon cancer.

Differential expression of colon cancer associated transcript1 (CCAT1) along the colonic adenoma-carcinoma sequence.

PubMed

Alaiyan, Bilal; Ilyayev, Nadia; Stojadinovic, Alexander; Izadjoo, Mina; Roistacher, Marina; Pavlov, Vera; Tzivin, Victoria; Halle, David; Pan, Honguang; Trink, Barry; Gure, Ali O; Nissan, Aviram

2013-04-17

The transition from normal epithelium to adenoma and, to invasive carcinoma in the human colon is associated with acquired molecular events taking 5-10 years for malignant transformation. We discovered CCAT1, a non-coding RNA over-expressed in colon cancer (CC), but not in normal tissues, thereby making it a potential disease-specific biomarker. We aimed to define and validate CCAT1 as a CC-specific biomarker, and to study CCAT1 expression across the adenoma-carcinoma sequence of CC tumorigenesis. Tissue samples were obtained from patients undergoing resection for colonic adenoma(s) or carcinoma. Normal colonic tissue (n = 10), adenomatous polyps (n = 18), primary tumor tissue (n = 22), normal mucosa adjacent to primary tumor (n = 16), and lymph node(s) (n = 20), liver (n = 8), and peritoneal metastases (n = 19) were studied. RNA was extracted from all tissue samples, and CCAT1 expression was analyzed using quantitative real time-PCR (qRT-PCR) with confirmatory in-situ hybridization (ISH). Borderline expression of CCAT1 was identified in normal tissue obtained from patients with benign conditions [mean Relative Quantity (RQ) = 5.9]. Significant relative CCAT1 up-regulation was observed in adenomatous polyps (RQ = 178.6 ± 157.0; p = 0.0012); primary tumor tissue (RQ = 64.9 ± 56.9; p = 0.0048); normal mucosa adjacent to primary tumor (RQ = 17.7 ± 21.5; p = 0.09); lymph node, liver and peritoneal metastases (RQ = 11,414.5 ± 12,672.9; 119.2 ± 138.9; 816.3 ± 2,736.1; p = 0.0001, respectively). qRT-PCR results were confirmed by ISH, demonstrating significant correlation between CCAT1 up-regulation measured using these two methods. CCAT1 is up-regulated across the colon adenoma-carcinoma sequence. This up-regulation is evident in pre-malignant conditions and through all disease stages, including advanced metastatic disease suggesting a role in both tumorigenesis and the

Colonization of plants by human pathogenic bacteria in the course of organic vegetable production.

PubMed

Hofmann, Andreas; Fischer, Doreen; Hartmann, Anton; Schmid, Michael

2014-01-01

In recent years, increasing numbers of outbreaks caused by the consumption of vegetables contaminated with human pathogenic bacteria were reported. The application of organic fertilizers during vegetable production is one of the possible reasons for contamination with those pathogens. In this study laboratory experiments in axenic and soil systems following common practices in organic farming were conducted to identify the minimal dose needed for bacterial colonization of plants and to identify possible factors like bacterial species or serovariation, plant species or organic fertilizer types used, influencing the success of plant colonization by human pathogenic bacteria. Spinach and corn salad were chosen as model plants and were inoculated with different concentrations of Salmonella enterica sv. Weltevreden, Listeria monocytogenes sv. 4b and EGD-E sv. 1/2a either directly (axenic system) or via agricultural soil amended with spiked organic fertilizers (soil system). In addition to PCR- and culture-based detection methods, fluorescence in situ hybridization (FISH) was applied in order to localize bacteria on or in plant tissues. Our results demonstrate that shoots were colonized by the pathogenic bacteria at inoculation doses as low as 4 × 10 CFU/ml in the axenic system or 4 × 10(5) CFU/g in the soil system. In addition, plant species dependent effects were observed. Spinach was colonized more often and at lower inoculation doses compared to corn salad. Differential colonization sites on roots, depending on the plant species could be detected using FISH-CLSM analysis. Furthermore, the transfer of pathogenic bacteria to plants via organic fertilizers was observed more often and at lower initial inoculation doses when fertilization was performed with inoculated slurry compared to inoculated manure. Finally, it could be shown that by introducing a simple washing step, the bacterial contamination was reduced in most cases or even was removed completely in some

Colonization of plants by human pathogenic bacteria in the course of organic vegetable production

PubMed Central

Hofmann, Andreas; Fischer, Doreen; Hartmann, Anton; Schmid, Michael

2014-01-01

In recent years, increasing numbers of outbreaks caused by the consumption of vegetables contaminated with human pathogenic bacteria were reported. The application of organic fertilizers during vegetable production is one of the possible reasons for contamination with those pathogens. In this study laboratory experiments in axenic and soil systems following common practices in organic farming were conducted to identify the minimal dose needed for bacterial colonization of plants and to identify possible factors like bacterial species or serovariation, plant species or organic fertilizer types used, influencing the success of plant colonization by human pathogenic bacteria. Spinach and corn salad were chosen as model plants and were inoculated with different concentrations of Salmonella enterica sv. Weltevreden, Listeria monocytogenes sv. 4b and EGD-E sv. 1/2a either directly (axenic system) or via agricultural soil amended with spiked organic fertilizers (soil system). In addition to PCR- and culture-based detection methods, fluorescence in situ hybridization (FISH) was applied in order to localize bacteria on or in plant tissues. Our results demonstrate that shoots were colonized by the pathogenic bacteria at inoculation doses as low as 4 × 10 CFU/ml in the axenic system or 4 × 105 CFU/g in the soil system. In addition, plant species dependent effects were observed. Spinach was colonized more often and at lower inoculation doses compared to corn salad. Differential colonization sites on roots, depending on the plant species could be detected using FISH-CLSM analysis. Furthermore, the transfer of pathogenic bacteria to plants via organic fertilizers was observed more often and at lower initial inoculation doses when fertilization was performed with inoculated slurry compared to inoculated manure. Finally, it could be shown that by introducing a simple washing step, the bacterial contamination was reduced in most cases or even was removed completely in some cases

Differences Between Colon Cancer Primaries and Metastases Using a Molecular Assay for Tumor Radiation Sensitivity Suggest Implications for Potential Oligometastatic SBRT Patient Selection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmed, Kamran A.; Fulp, William J.; Berglund, Anders E.

2015-07-15

Purpose: We previously developed a multigene expression model of tumor radiation sensitivity index (RSI) with clinical validation in multiple independent cohorts (breast, rectal, esophageal, and head and neck patients). The purpose of this study was to assess differences between RSI scores in primary colon cancer and metastases. Methods and Materials: Patients were identified from our institutional review board–approved prospective observational protocol. A total of 704 metastatic and 1362 primary lesions were obtained from a de-identified metadata pool. RSI was calculated using the previously published rank-based algorithm. An independent cohort of 29 lung or liver colon metastases treated with 60 Gy in 5more » fractions stereotactic body radiation therapy (SBRT) was used for validation. Results: The most common sites of metastases included liver (n=374; 53%), lung (n=116; 17%), and lymph nodes (n=40; 6%). Sixty percent of metastatic tumors, compared with 54% of primaries, were in the RSI radiation-resistant peak, suggesting metastatic tumors may be slightly more radiation resistant than primaries (P=.01). In contrast, when we analyzed metastases based on anatomical site, we uncovered large differences in RSI. The median RSIs for metastases in descending order of radiation resistance were ovary (0.48), abdomen (0.47), liver (0.43), brain (0.42), lung (0.32), and lymph nodes (0.31) (P<.0001). These findings were confirmed when the analysis was restricted to lesions from the same patient (n=139). In our independent cohort of treated lung and liver metastases, lung metastases had an improved local control rate compared to that in patients with liver metastases (2-year local control rate of 100% vs 73.0%, respectively; P=.026). Conclusions: Assessment of radiation sensitivity between primary and metastatic tissues of colon cancer histology revealed significant differences based on anatomical location of metastases. These initial results warrant validation in a

Microbial colonization and lung function in adolescents with cystic fibrosis.

PubMed

Hector, Andreas; Kirn, Tobias; Ralhan, Anjali; Graepler-Mainka, Ute; Berenbrinker, Sina; Riethmueller, Joachim; Hogardt, Michael; Wagner, Marlies; Pfleger, Andreas; Autenrieth, Ingo; Kappler, Matthias; Griese, Matthias; Eber, Ernst; Martus, Peter; Hartl, Dominik

2016-05-01

With intensified antibiotic therapy and longer survival, patients with cystic fibrosis (CF) are colonized with a more complex pattern of bacteria and fungi. However, the clinical relevance of these emerging pathogens for lung function remains poorly defined. The aim of this study was to assess the association of bacterial and fungal colonization patterns with lung function in adolescent patients with CF. Microbial colonization patterns and lung function parameters were assessed in 770 adolescent European (German/Austrian) CF patients in a retrospective study (median follow-up time: 10years). Colonization with Pseudomonas aeruginosa and MRSA were most strongly associated with loss of lung function, while mainly colonization with Haemophilus influenzae was associated with preserved lung function. Aspergillus fumigatus was the only species that was associated with an increased risk for infection with P. aeruginosa. Microbial interaction analysis revealed three distinct microbial clusters within the longitudinal course of CF lung disease. Collectively, this study identified potentially protective and harmful microbial colonization patterns in adolescent CF patients. Further studies in different patient cohorts are required to evaluate these microbial patterns and to assess their clinical relevance. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

A model for bacterial colonization of sinking aggregates.

PubMed

Bearon, R N

2007-01-01

Sinking aggregates provide important nutrient-rich environments for marine bacteria. Quantifying the rate at which motile bacteria colonize such aggregations is important in understanding the microbial loop in the pelagic food web. In this paper, a simple analytical model is presented to predict the rate at which bacteria undergoing a random walk encounter a sinking aggregate. The model incorporates the flow field generated by the sinking aggregate, the swimming behavior of the bacteria, and the interaction of the flow with the swimming behavior. An expression for the encounter rate is computed in the limit of large Péclet number when the random walk can be approximated by a diffusion process. Comparison with an individual-based numerical simulation is also given.

Walnut Phenolic Extract and Its Bioactive Compounds Suppress Colon Cancer Cell Growth by Regulating Colon Cancer Stemness.

PubMed

Lee, Jisoo; Kim, Yoo-Sun; Lee, JaeHwan; Heo, Seung Chul; Lee, Kook Lae; Choi, Sang-Woon; Kim, Yuri

2016-07-21

Walnut has been known for its health benefits, including anti-cardiovascular disease and anti-oxidative properties. However, there is limited evidence elucidating its effects on cancer stem cells (CSCs) which represent a small subset of cancer cells that provide resistance against chemotherapy. This study aimed to evaluate the anti-CSCs potential of walnut phenolic extract (WPE) and its bioactive compounds, including (+)-catechin, chlorogenic acid, ellagic acid, and gallic acid. In the present study, CD133⁺CD44⁺ cells were isolated from HCT116 cells using fluorescence-activated cell sorting (FACS) and then treated with WPE. As a result, survival of the CD133⁺CD44⁺ HCT116 cells was inhibited and cell differentiation was induced by WPE. In addition, WPE down-regulated the CSC markers, CD133, CD44, DLK1, and Notch1, as well as the β-catenin/p-GSK3β signaling pathway. WPE suppressed the self-renewal capacity of CSCs. Furthermore, the WPE exhibited stronger anti-CSC effects than its individual bioactive compounds. Finally, the WPE inhibited specific CSC markers in primary colon cancer cells isolated from primary colon tumor. These results suggest that WPE can suppress colon cancer by regulating the characteristics of colon CSCs.

Walnut Phenolic Extract and Its Bioactive Compounds Suppress Colon Cancer Cell Growth by Regulating Colon Cancer Stemness

PubMed Central

Lee, Jisoo; Kim, Yoo-Sun; Lee, JaeHwan; Heo, Seung Chul; Lee, Kook Lae; Choi, Sang-Woon; Kim, Yuri

2016-01-01

Walnut has been known for its health benefits, including anti-cardiovascular disease and anti-oxidative properties. However, there is limited evidence elucidating its effects on cancer stem cells (CSCs) which represent a small subset of cancer cells that provide resistance against chemotherapy. This study aimed to evaluate the anti-CSCs potential of walnut phenolic extract (WPE) and its bioactive compounds, including (+)-catechin, chlorogenic acid, ellagic acid, and gallic acid. In the present study, CD133+CD44+ cells were isolated from HCT116 cells using fluorescence-activated cell sorting (FACS) and then treated with WPE. As a result, survival of the CD133+CD44+ HCT116 cells was inhibited and cell differentiation was induced by WPE. In addition, WPE down-regulated the CSC markers, CD133, CD44, DLK1, and Notch1, as well as the β-catenin/p-GSK3β signaling pathway. WPE suppressed the self-renewal capacity of CSCs. Furthermore, the WPE exhibited stronger anti-CSC effects than its individual bioactive compounds. Finally, the WPE inhibited specific CSC markers in primary colon cancer cells isolated from primary colon tumor. These results suggest that WPE can suppress colon cancer by regulating the characteristics of colon CSCs. PMID:27455311

Helminth Colonization Is Associated with Increased Diversity of the Gut Microbiota

PubMed Central

Lee, Soo Ching; Tang, Mei San; Lim, Yvonne A. L.; Choy, Seow Huey; Kurtz, Zachary D.; Cox, Laura M.; Gundra, Uma Mahesh; Cho, Ilseung; Bonneau, Richard; Blaser, Martin J.; Chua, Kek Heng; Loke, P'ng

2014-01-01

Soil-transmitted helminths colonize more than 1.5 billion people worldwide, yet little is known about how they interact with bacterial communities in the gut microbiota. Differences in the gut microbiota between individuals living in developed and developing countries may be partly due to the presence of helminths, since they predominantly infect individuals from developing countries, such as the indigenous communities in Malaysia we examine in this work. We compared the composition and diversity of bacterial communities from the fecal microbiota of 51 people from two villages in Malaysia, of which 36 (70.6%) were infected by helminths. The 16S rRNA V4 region was sequenced at an average of nineteen thousand sequences per samples. Helminth-colonized individuals had greater species richness and number of observed OTUs with enrichment of Paraprevotellaceae, especially with Trichuris infection. We developed a new approach of combining centered log-ratio (clr) transformation for OTU relative abundances with sparse Partial Least Squares Discriminant Analysis (sPLS-DA) to enable more robust predictions of OTU interrelationships. These results suggest that helminths may have an impact on the diversity, bacterial community structure and function of the gut microbiota. PMID:24851867

Host- and microbe determinants that may influence the success of S. aureus colonization

PubMed Central

Johannessen, Mona; Sollid, Johanna E.; Hanssen, Anne-Merethe

2012-01-01

Staphylococcus aureus may cause serious skin and soft tissue infections, deep abscesses, endocarditis, osteomyelitis, pneumonia, and sepsis. S. aureus persistently colonizes 25–30% of the adult human population, and S. aureus carriers have an increased risk for infections caused by the bacterium. The major site of colonization is the nose, i.e., the vestibulum nasi, which is covered with ordinary skin and hair follicles. Several host and microbe determinants are assumed to be associated with colonization. These include the presence and expression level of bacterial adhesins, which can adhere to various proteins in the extracellular matrix or on the cellular surface of human skin. The host expresses several antimicrobial peptides and lipids. The level of β-defensin 3, free sphingosine, and cis-6-hexadecenoic acid are found to be associated with nasal carriage of S. aureus. Other host factors are certain polymorphisms in Toll-like receptor 2, mannose-binding lectin, C-reactive protein, glucocorticoid-, and vitamin D receptor. Additional putative determinants for carriage include genetic variation and expression of microbial surface components recognizing adhesive matrix molecules and their interaction partners, as well as variation among humans in the ability of recognizing and responding appropriately to the bacteria. Moreover, the available microflora may influence the success of S. aureus colonization. In conclusion, colonization is a complex interplay between the bacteria and its host. Several bacterial and host factors are involved, and an increased molecular understanding of these are needed. PMID:22919647

Host- and microbe determinants that may influence the success of S. aureus colonization.

PubMed

Johannessen, Mona; Sollid, Johanna E; Hanssen, Anne-Merethe

2012-01-01

Staphylococcus aureus may cause serious skin and soft tissue infections, deep abscesses, endocarditis, osteomyelitis, pneumonia, and sepsis. S. aureus persistently colonizes 25-30% of the adult human population, and S. aureus carriers have an increased risk for infections caused by the bacterium. The major site of colonization is the nose, i.e., the vestibulum nasi, which is covered with ordinary skin and hair follicles. Several host and microbe determinants are assumed to be associated with colonization. These include the presence and expression level of bacterial adhesins, which can adhere to various proteins in the extracellular matrix or on the cellular surface of human skin. The host expresses several antimicrobial peptides and lipids. The level of β-defensin 3, free sphingosine, and cis-6-hexadecenoic acid are found to be associated with nasal carriage of S. aureus. Other host factors are certain polymorphisms in Toll-like receptor 2, mannose-binding lectin, C-reactive protein, glucocorticoid-, and vitamin D receptor. Additional putative determinants for carriage include genetic variation and expression of microbial surface components recognizing adhesive matrix molecules and their interaction partners, as well as variation among humans in the ability of recognizing and responding appropriately to the bacteria. Moreover, the available microflora may influence the success of S. aureus colonization. In conclusion, colonization is a complex interplay between the bacteria and its host. Several bacterial and host factors are involved, and an increased molecular understanding of these are needed.

Unique Metabolic Adaptations Dictate Distal Organ-Specific Metastatic Colonization

PubMed Central

Schild, Tanya; Low, Vivien; Blenis, John; Gomes, Ana P.

2018-01-01

Summary Metastases arising from tumors have the proclivity to colonize specific organs, suggesting that they must rewire their biology to meet the demands of the organ colonized, thus altering their primary properties. Each metastatic site presents distinct metabolic challenges to a colonizing cancer cell, ranging from fuel and oxygen availability to oxidative stress. Here, we discuss the organ-specific metabolic adaptations cancer cells must undergo, which provide the ability to overcome the unique barriers to colonization in foreign tissues and establish the metastatic tissue tropism phenotype. PMID:29533780

Morbidity predicting factors of penetrating colon injuries.

PubMed

Mickevicius, A; Valeikaite, G; Tamelis, A; Saladzinskas, Z; Svagzdys, S; Pavalkis, D

2010-01-01

To analyze patients suffering from penetrating colon injuries management, clinical outcomes and factors, which predict higher morbidity and complications rate. this was a retrospective analysis of prospectively collected data from patients with injured colon from 1995 to 2008. Age, time till operation, systolic blood pressure, part of injured colon, fecal contamination, PATI were registered. Monovariate and multivariate logistic regression was performed to determine higher morbidity predictive factors. 61 patients had penetrating colon injuries. Major fecal contamination of the peritoneal cavity and systolic blood pressure lower than 90 mmHg are independent factors determining the fecal diversion operation. Primary repair group analysis establish that major fecal contamination and systolic blood pressure lower than 90 mmHg OR = 4.2 and 0.96 were significant risk factors, which have contributed to the development of postoperative complications. And systolic blood pressure lower than 90 mmHg and PATI 20 predict OR = 0.05 and 2.61 higher morbidity. Fecal contamination of the peritoneal cavity and hypotension were determined to be crucial in choice of performing fecal diversion or primary repair. But the same criteria and PATI predict higher rate of postoperative complications and higher morbidity.

Plasmid Dynamics in KPC-Positive Klebsiella pneumoniae during Long-Term Patient Colonization

PubMed Central

Park, Morgan; Deming, Clayton; Thomas, Pamela J.; Young, Alice C.; Coleman, Holly; Sison, Christina; Weingarten, Rebecca A.; Lau, Anna F.; Dekker, John P.; Palmore, Tara N.; Frank, Karen M.

2016-01-01

ABSTRACT Carbapenem-resistant Klebsiella pneumoniae strains are formidable hospital pathogens that pose a serious threat to patients around the globe due to a rising incidence in health care facilities, high mortality rates associated with infection, and potential to spread antibiotic resistance to other bacterial species, such as Escherichia coli. Over 6 months in 2011, 17 patients at the National Institutes of Health (NIH) Clinical Center became colonized with a highly virulent, transmissible carbapenem-resistant strain of K. pneumoniae. Our real-time genomic sequencing tracked patient-to-patient routes of transmission and informed epidemiologists’ actions to monitor and control this outbreak. Two of these patients remained colonized with carbapenemase-producing organisms for at least 2 to 4 years, providing the opportunity to undertake a focused genomic study of long-term colonization with antibiotic-resistant bacteria. Whole-genome sequencing studies shed light on the underlying complex microbial colonization, including mixed or evolving bacterial populations and gain or loss of plasmids. Isolates from NIH patient 15 showed complex plasmid rearrangements, leaving the chromosome and the blaKPC-carrying plasmid intact but rearranging the two other plasmids of this outbreak strain. NIH patient 16 has shown continuous colonization with blaKPC-positive organisms across multiple time points spanning 2011 to 2015. Genomic studies defined a complex pattern of succession and plasmid transmission across two different K. pneumoniae sequence types and an E. coli isolate. These findings demonstrate the utility of genomic methods for understanding strain succession, genome plasticity, and long-term carriage of antibiotic-resistant organisms. PMID:27353756

Fusobacterium nucleatum infection of colonic cells stimulates MUC2 mucin and tumor necrosis factor alpha.

PubMed

Dharmani, Poonam; Strauss, Jaclyn; Ambrose, Christian; Allen-Vercoe, Emma; Chadee, Kris

2011-07-01

The etiology of inflammatory bowel disease is not completely known, but it is influenced by the presence of normal gut microflora as well as yet-unrecognized pathogens. The anaerobic, Gram-negative bacterial species Fusobacterium nucleatum is a common resident of the human mouth and gut and varies in its pathogenic potential. In this study, we demonstrate that highly invasive F. nucleatum isolates derived from the inflamed guts of Crohn's disease patients evoked significantly greater MUC2 and tumor necrosis factor alpha (TNF-α) gene expression than minimally invasive strains isolated from the noninflamed gut in human colonic epithelial cells and in a rat ligated colonic loop model of infection. Only live F. nucleatum induced mucin secretion and TNF-α expression in direct contact with and/or during invasion of colonic cells. In rat colons, mucin secretion was augmented in response to a highly invasive F. nucleatum isolate but was unaffected by treatment with a minimally invasive strain. Taken together, these studies reveal that F. nucleatum may represent a challenging pathogen in the etiology of gut inflammatory diseases and highlight the importance of different pathotypes of candidate bacterial species in disease pathogenesis.

Bacterial growth, flow, and mixing shape human gut microbiota density and composition.

PubMed

Arnoldini, Markus; Cremer, Jonas; Hwa, Terence

2018-03-13

The human gut microbiota is highly dynamic, and host physiology and diet exert major influences on its composition. In our recent study, we integrated new quantitative measurements on bacterial growth physiology with a reanalysis of published data on human physiology to build a comprehensive modeling framework. This can generate predictions of how changes in different host factors influence microbiota composition. For instance, hydrodynamic forces in the colon, along with colonic water absorption that manifests as transit time, exert a major impact on microbiota density and composition. This can be mechanistically explained by their effect on colonic pH which directly affects microbiota competition for food. In this addendum, we describe the underlying analysis in more detail. In particular, we discuss the mixing dynamics of luminal content by wall contractions and its implications for bacterial growth and density, as well as the broader implications of our insights for the field of gut microbiota research.

Gut microbial diversity is reduced and is associated with colonic inflammation in a piglet model of short bowel syndrome

PubMed Central

Lapthorne, Susan; Pereira-Fantini, Prue M.; Fouhy, Fiona; Wilson, Guineva; Thomas, Sarah L.; Dellios, Nicole L.; Scurr, Michelle; O’Sullivan, Orla; Ross, R. Paul; Stanton, Catherine; Fitzgerald, Gerald F.; Cotter, Paul D.; Bines, Julie E.

2013-01-01

Background and objectives Following small bowel resection (SBR), the luminal environment is altered, which contributes to clinical manifestations of short bowel syndrome (SBS) including malabsorption, mucosal inflammation and bacterial overgrowth. However, the impact of SBR on the colon has not been well-defined. The aims of this study were to characterize the colonic microbiota following SBR and to assess the impact of SBR on mucosal inflammation in the colon. Results Analysis of the colonic microbiota demonstrated that there was a significant level of dysbiosis both two and six weeks post-SBR, particularly in the phylum Firmicutes, coupled with a decrease in overall bacterial diversity in the colon. This decrease in diversity was associated with an increase in colonic inflammation six weeks post-surgery. Methods Female (4-week old) piglets (5−6/group) received a 75% SBR, a transection (sham) or no surgery. Compositional analysis of the colonic microbiota was performed by high-throughput sequencing, two- and six-weeks post-surgery. The gene expression of the pro-inflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, IL-18 and tumor necrosis factor (TNF)-α in the colonic mucosa was assessed by qRT-PCR and the number of macrophages and percentage inducible nitric oxide synthase (iNOS) staining in the colonic epithelium were quantified by immunohistochemistry. Conclusions SBR significantly decreased the diversity of the colonic microbiota and this was associated with an increase in colonic mucosal inflammation. This study supports the hypothesis that SBR has a significant impact on the colon and that this may play an important role in defining clinical outcome. PMID:23549027

Comparative Analysis of Bacterial Community Composition and Structure in Clinically Symptomatic and Asymptomatic Central Venous Catheters

PubMed Central

Stressmann, Franziska A.; Couve-Deacon, Elodie; Chainier, Delphine; Chauhan, Ashwini; Wessel, Aimee; Durand-Fontanier, Sylvaine; Escande, Marie-Christine; Kriegel, Irène; Francois, Bruno; Ploy, Marie-Cécile

2017-01-01

ABSTRACT Totally implanted venous access ports (TIVAPs) are commonly used catheters for the management of acute or chronic pathologies. Although these devices improve health care, repeated use of this type of device for venous access over long periods of time is also associated with risk of colonization and infection by pathogenic bacteria, often originating from skin. However, although the skin microbiota is composed of both pathogenic and nonpathogenic bacteria, the extent and the consequences of TIVAP colonization by nonpathogenic bacteria have rarely been studied. Here, we used culture-dependent and 16S rRNA gene-based culture-independent approaches to identify differences in bacterial colonization of TIVAPs obtained from two French hospitals. To explore the relationships between nonpathogenic organisms colonizing TIVAPs and the potential risk of infection, we analyzed the bacterial community parameters between TIVAPs suspected (symptomatic) or not (asymptomatic) of infection. Although we did not find a particular species assemblage or community marker to distinguish infection risk on an individual sample level, we identified differences in bacterial community composition, diversity, and structure between clinically symptomatic and asymptomatic TIVAPs that could be explored further. This study therefore provides a new view of bacterial communities and colonization patterns in intravascular TIVAPs and suggests that microbial ecology approaches could improve our understanding of device-associated infections and could be a prognostic tool to monitor the evolution of bacterial communities in implants and their potential susceptibility to infections. IMPORTANCE Totally implanted venous access ports (TIVAPs) are commonly used implants for the management of acute or chronic pathologies. Although their use improves the patient’s health care and quality of life, they are associated with a risk of infection and subsequent clinical complications, often leading to

Infection processes of xylem-colonizing pathogenic bacteria: possible explanations for the scarcity of qualitative disease resistance genes against them in crops.

PubMed

Bae, Chungyun; Han, Sang Wook; Song, Yu-Rim; Kim, Bo-Young; Lee, Hyung-Jin; Lee, Je-Min; Yeam, Inhwa; Heu, Sunggi; Oh, Chang-Sik

2015-07-01

Disease resistance against xylem-colonizing pathogenic bacteria in crops. Plant pathogenic bacteria cause destructive diseases in many commercially important crops. Among these bacteria, eight pathogens, Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, X. campestris pv. campestris, Erwinia amylovora, Pantoea stewartii subsp. stewartii, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. actinidiae, and Xylella fastidiosa, infect their host plants through different infection sites and paths and eventually colonize the xylem tissues of their host plants, resulting in wilting symptoms by blocking water flow or necrosis of xylem tissues. Noticeably, only a relatively small number of resistant cultivars in major crops against these vascular bacterial pathogens except X. oryzae pv. oryzae have been found or generated so far, although these pathogens threaten productivity of major crops. In this review, we summarize the lifestyles of major xylem-colonizing bacterial pathogens and then discuss the progress of current research on disease resistance controlled by qualitative disease resistance genes or quantitative trait loci against them. Finally, we propose infection processes of xylem-colonizing bacterial pathogens as one of possible reasons for why so few qualitative disease resistance genes against these pathogens have been developed or identified so far in crops.

Carrying Capacity and Colonization Dynamics of Curvibacter in the Hydra Host Habitat

PubMed Central

Wein, Tanita; Dagan, Tal; Fraune, Sebastian; Bosch, Thomas C. G.; Reusch, Thorsten B. H.; Hülter, Nils F.

2018-01-01

Most eukaryotic species are colonized by a microbial community – the microbiota – that is acquired during early life stages and is critical to host development and health. Much research has focused on the microbiota biodiversity during the host life, however, empirical data on the basic ecological principles that govern microbiota assembly is lacking. Here we quantify the contribution of colonizer order, arrival time and colonization history to microbiota assembly on a host. We established the freshwater polyp Hydra vulgaris and its dominant colonizer Curvibacter as a model system that enables the visualization and quantification of colonizer population size at the single cell resolution, in vivo, in real time. We estimate the carrying capacity of a single Hydra polyp as 2 × 105 Curvibacter cells, which is robust among individuals and time. Colonization experiments reveal a clear priority effect of first colonizers that depends on arrival time and colonization history. First arriving colonizers achieve a numerical advantage over secondary colonizers within a short time lag of 24 h. Furthermore, colonizers primed for the Hydra habitat achieve a numerical advantage in the absence of a time lag. These results follow the theoretical expectations for any bacterial habitat with a finite carrying capacity. Thus, Hydra colonization and succession processes are largely determined by the habitat occupancy over time and Curvibacter colonization history. Our experiments provide empirical data on the basic steps of host-associated microbiota establishment – the colonization stage. The presented approach supplies a framework for studying habitat characteristics and colonization dynamics within the host–microbe setting. PMID:29593687

The role of respiratory viruses in the etiology of bacterial pneumonia: An ecological perspective.

PubMed

Lee, Kyu Han; Gordon, Aubree; Foxman, Betsy

2016-02-15

Pneumonia is the leading cause of death among children less than 5 years old worldwide. A wide range of viral, bacterial and fungal agents can cause pneumonia: although viruses are the most common etiologic agent, the severity of clinical symptoms associated with bacterial pneumonia and increasing antibiotic resistance makes bacterial pneumonia a major public health concern. Bacterial pneumonia can follow upper respiratory viral infection and complicate lower respiratory viral infection. Secondary bacterial pneumonia is a major cause of influenza-related deaths. In this review, we evaluate the following hypotheses: (i) respiratory viruses influence the etiology of pneumonia by altering bacterial community structure in the upper respiratory tract (URT) and (ii) respiratory viruses promote or inhibit colonization of the lower respiratory tract (LRT) by certain bacterial species residing in the URT. We conducted a systematic review of the literature to examine temporal associations between respiratory viruses and bacteria and a targeted review to identify potential mechanisms of interactions. We conclude that viruses both alter the bacterial community in the URT and promote bacterial colonization of the LRT. However, it is uncertain whether changes in the URT bacterial community play a substantial role in pneumonia etiology. The exception is Streptococcus pneumoniae where a strong link between viral co-infection, increased carriage and pneumococcal pneumonia has been established. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Aspergillus fumigatus colonization of punctal plugs.

PubMed

Tabbara, Khalid F

2007-01-01

Punctal plugs are used in patients with dry eye syndrome to preserve the tears. In this report, I present two cases of Aspergillus fumigatus colonization of punctal plugs. Observational series of two cases. Approval was obtained from the institutional review board. Two men aged 29 and 31 years developed black spots inside the hole of punctal plug, which looked like eyeliner deposits. The deposits inside the hole of the plug in each patient were removed and cultured. Cultures of the two punctal plugs black deposits grew A fumigatus. Bacterial cultures were negative. Colonization of the punctal plug hole with A fumigatus was observed in two cases. It is recommended that punctal plugs be removed in patients undergoing refractive or intraocular procedures or in patients who are receiving topical corticosteroids. Current punctal plugs should be redesigned to avoid the presence of an inserter hole.

Interactions of Seedborne Bacterial Pathogens with Host and Non-Host Plants in Relation to Seed Infestation and Seedling Transmission

PubMed Central

Dutta, Bhabesh; Gitaitis, Ronald; Smith, Samuel; Langston, David

2014-01-01

The ability of seed-borne bacterial pathogens (Acidovorax citrulli, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, Xanthomonas euvesicatoria, and Pseudomonas syringae pv. glycinea) to infest seeds of host and non-host plants (watermelon, tomato, pepper, and soybean) and subsequent pathogen transmission to seedlings was investigated. A non-pathogenic, pigmented strain of Serratia marcescens was also included to assess a null-interacting situation with the same plant species. Flowers of host and non-host plants were inoculated with 1×106 colony forming units (CFUs)/flower for each bacterial species and allowed to develop into fruits or umbels (in case of onion). Seeds harvested from each host/non-host bacterial species combination were assayed for respective bacteria by plating on semi-selective media. Additionally, seedlots for each host/non-host bacterial species combination were also assayed for pathogen transmission by seedling grow-out (SGO) assays under greenhouse conditions. The mean percentage of seedlots infested with compatible and incompatible pathogens was 31.7 and 30.9% (by plating), respectively and they were not significantly different (P = 0.67). The percentage of seedlots infested with null-interacting bacterial species was 16.8% (by plating) and it was significantly lower than the infested lots generated with compatible and incompatible bacterial pathogens (P = 0.03). None of the seedlots with incompatible/null-interacting bacteria developed symptoms on seedlings; however, when seedlings were assayed for epiphytic bacterial presence, 19.5 and 9.4% of the lots were positive, respectively. These results indicate that the seeds of non-host plants can become infested with incompatible and null-interacting bacterial species through flower colonization and they can be transmitted via epiphytic colonization of seedlings. In addition, it was also observed that flowers and seeds of non-host plants can be colonized

Association Between Contact Sports and Colonization with Staphylococcus aureus in a Prospective Cohort of Collegiate Athletes.

PubMed

Jiménez-Truque, Natalia; Saye, Elizabeth J; Soper, Nicole; Saville, Benjamin R; Thomsen, Isaac; Edwards, Kathryn M; Creech, C Buddy

2017-05-01

Athletes have a higher risk of infection with Staphylococcus aureus than the general population. Most studies in athletes have included primarily male contact sports participants and have not assessed S. aureus carriage over time. We aimed to examine the epidemiology and risk factors of S. aureus carriage in a cohort of male and female collegiate athletes. We conducted a prospective cohort study of 377 varsity collegiate athletes from August 2008 to April 2010. A baseline questionnaire ascertained risk factors for colonization. Nasal and oropharyngeal swabs were obtained at enrollment and monthly thereafter to detect S. aureus colonization. The primary outcome was S. aureus colonization, both with methicillin-susceptible and methicillin-resistant S. aureus, as defined by bacterial culture and molecular confirmation. Secondary outcomes were time to colonization with S. aureus and carriage profile, defined as non-carrier, intermittent carrier, or persistent carrier. Overall, 224 contact sports and 153 non-contact sports athletes were enrolled. Contact sports athletes had a higher risk of carrying S. aureus over time: They had higher odds of being colonized with MRSA (OR 2.36; 95 % CI 1.13-4.93) and they tended to carry S. aureus for longer periods of time (intermittent carriage OR 3.60; 95 % CI 2.02-6.40; persistent carriage OR 2.39; 95 % CI 1.21-4.72). Athletes engaged in contact sports also acquired S. aureus more quickly (HR 1.61; 95 % CI 1.02-2.55). Staphylococcus aureus carriage was common in contact sports athletes. These findings suggest that efforts to prevent transmission of S. aureus among athletes should be focused on contact sports teams.

Bacterial community succession in a high-altitude subarctic glacier foreland is a three-stage process.

PubMed

Kazemi, Sina; Hatam, Ido; Lanoil, Brian

2016-11-01

Alpine glaciers are retreating rapidly, exposing foreland minerals, which develop into soils. Bacterial communities in glacier forelands exhibit high rates of turnover and undergo dramatic shifts in composition within the first 50 years after deglaciation, followed by relative stabilization and convergence. This period of microbial development occurs simultaneously with plant colonization in most systems; thus, it remains unclear whether the changes in the bacterial communities occur primarily as the result of edaphic, climatic or biotic factors. We examined bacterial community structure along two replicate chronosequences within the glacial foreland of Duke River Glacier, Yukon, Canada. This foreland is estimated to include >200 years of bare soils before an appreciable grassline, likely due to the high latitude and altitude of the glacier. This enabled us to examine bacterial community development prior to plant colonization over a longer period than previous studies. We observed three successional groups in the chronosequence: (i) an 'early' group in soils of less than approximately 50 years since deglaciation; (ii) an 'intermediate' group within bare soils, after the early period but before the grassline, containing communities with a relatively high degree of variability in composition; and (iii) a 'grassline' group in soils collected after plant colonization with higher diversity but lower age-group variability in community composition. These findings suggest rapid replacement and addition of species better adapted to glacier foreland conditions followed by slower community shifts over the next 150 years and, finally, indications of a possible response to plant colonization. © 2016 John Wiley & Sons Ltd.

The management of colonic trauma in the damage control era

PubMed Central

Shazi, B; Bruce, JL; Laing, GL; Sartorius, B

2017-01-01

INTRODUCTION The purpose of this study was to audit our current management of colonic trauma, and to review our experience of colonic trauma in patients who underwent initial damage control (DC) surgery. METHODS All patients treated for colonic trauma between January 2012 and December 2014 by the Pietermaritzburg Metropolitan Trauma Service were included in the study. Data reviewed included mechanism of injury, method of management (primary repair [PR], primary diversion [PD] or DC) and outcome (complications and mortality rate). Results A total of 128 patients sustained a colonic injury during the study period. Ninety-seven per cent of the injuries were due to penetrating trauma. Of these cases, 56% comprised stab wounds (SWs) and 44% were gunshot wounds (GSWs). Management was by PR in 99, PD in 20 and DC surgery in 9 cases. Among the 69 SW victims, 57 underwent PR, 9 had PD and 3 required a DC procedure. Of the 55 GSW cases, 40 were managed with PR, 9 with PD and 6 with DC surgery. In the PR group, there were 16 colonic complications (5 cases of breakdown and 11 of wound sepsis). Overall, nine patients (7%) died. CONCLUSIONS PR of colonic trauma is safe and should be used for the majority of such injuries. Persistent acidosis, however, should be considered a contraindication. In unstable patients with complex injuries, the optimal approach is to perform DC surgery. In this situation, formal diversion is contraindicated, and the injury should be controlled and dropped back into the abdomen at the primary operation. At the repeat operation, if the physiological insult has been reversed, then formal repair of the colonic injury is acceptable. PMID:27659359

The management of colonic trauma in the damage control era.

PubMed

Shazi, B; Bruce, J L; Laing, G L; Sartorius, B; Clarke, D L

2017-01-01

INTRODUCTION The purpose of this study was to audit our current management of colonic trauma, and to review our experience of colonic trauma in patients who underwent initial damage control (DC) surgery. METHODS All patients treated for colonic trauma between January 2012 and December 2014 by the Pietermaritzburg Metropolitan Trauma Service were included in the study. Data reviewed included mechanism of injury, method of management (primary repair [PR], primary diversion [PD] or DC) and outcome (complications and mortality rate). Results A total of 128 patients sustained a colonic injury during the study period. Ninety-seven per cent of the injuries were due to penetrating trauma. Of these cases, 56% comprised stab wounds (SWs) and 44% were gunshot wounds (GSWs). Management was by PR in 99, PD in 20 and DC surgery in 9 cases. Among the 69 SW victims, 57 underwent PR, 9 had PD and 3 required a DC procedure. Of the 55 GSW cases, 40 were managed with PR, 9 with PD and 6 with DC surgery. In the PR group, there were 16 colonic complications (5 cases of breakdown and 11 of wound sepsis). Overall, nine patients (7%) died. CONCLUSIONS PR of colonic trauma is safe and should be used for the majority of such injuries. Persistent acidosis, however, should be considered a contraindication. In unstable patients with complex injuries, the optimal approach is to perform DC surgery. In this situation, formal diversion is contraindicated, and the injury should be controlled and dropped back into the abdomen at the primary operation. At the repeat operation, if the physiological insult has been reversed, then formal repair of the colonic injury is acceptable.

Impact of location on outcome after penetrating colon injuries.

PubMed

Sharpe, John P; Magnotti, Louis J; Weinberg, Jordan A; Zarzaur, Ben L; Shahan, Charles P; Parks, Nancy A; Fabian, Timothy C; Croce, Martin A

2012-12-01

Most studies examining suture line failure after penetrating colon injuries have focused on right- versus left-sided injuries. In our institution, operative decisions (resection plus anastomosis vs. diversion) are based on a defined management algorithm regardless of injury location. The purpose of this study was to evaluate the effect of injury location on outcomes after penetrating colon injuries. Consecutive patients with full thickness penetrating colon injuries for 13 years were stratified by age, injury location and mechanism, and severity of shock. According to the algorithm, patients with nondestructive injuries underwent primary repair. Destructive wounds underwent resection plus anastomosis in the absence of comorbidities or large preoperative or intraoperative transfusion requirements (>6 U of packed red blood cells); otherwise, they were diverted. Injury location was defined as ascending, transverse, descending (including splenic flexure), and sigmoid. Multivariable logistic regression was performed to determine whether injury location was an independent predictor of either morbidity or mortality. Four hundred sixty-nine patients were identified: 314 (67%) underwent primary repair and 155 (33%) underwent resection. Most injuries involved the transverse colon (39%), followed by the ascending colon (26%), the descending colon (21%), and the sigmoid colon (14%). Overall, there were 13 suture line failures (3%) and 72 abscesses (15%). Most suture line failures involved injuries to the descending colon (p = 0.06), whereas most abscesses followed injuries to the ascending colon (p = 0.37). Multivariable logistic regression failed to identify injury location as an independent predictor of either morbidity or mortality after adjusting for 24-hour transfusions, base excess, shock index, injury mechanism, and operative management. Injury location did not affect morbidity or mortality after penetrating colon injuries. Nondestructive injuries should be primarily

Urgent surgery for complicated colonic diverticula.

PubMed

Funariu, Gheorghe; Binţinţan, Vasile; Seicean, Radu

2006-03-01

The AIM of this retrospective study was to evaluate the emergency surgical treatment of life-threatening complications of colonic diverticula. In the last 11 years, 22 of 101 patients with colonic diverticula (22.1%) underwent urgent surgery for acute complications: perforated gangrenous diverticulitis with generalized peritonitis (n=8) or pericolic abscess (n=8), acute bowel obstruction (n=4) and severe diverticular bleeding (n=2). In all patients with diffuse peritonitis or acute obstruction the indication for surgery was decided on clinical basis and the complicated diverticula were recognized only intra-operatively. Emergency surgical strategy differed according to the type of complication and the biologic condition of the patient: segmental colectomy and primary anastomosis for diverticular perforation (n=4), colonic stenosis (n=3) or diverticular bleeding (n=2); Hartmann resection with late reconnecting anastomosis in patients with diverticular perforation (n=5) or colonic obstruction (n=1); diverticulectomy with peritoneal drainage (n=2) and colostomy and drainage followed by secondary colectomy (n=5) for diverticular perforations in patients with poor general condition. Only one patient (4.5%) died post-operatively of multiple organ failure from generalized peritonitis. There was no anastomotic leakage in patients with primary anastomosis. Six patients (27.2%) developed wound infection. Hospital stay ranged between 11 and 60 days, significantly longer in cases with two-stage operations. Primary colectomy with immediate or delayed anastomosis is the best surgical procedure for acute divericular complications in patients with good biologic status. Two-stage operations such as colostomy and drainage coupled with late colectomy remain the viable alternative in patients with advanced disease and critical biologic condition.

Biocontrol of verticillium wilt and colonization of cotton plants by an endophytic bacterial isolate.

PubMed

Li, C-H; Shi, L; Han, Q; Hu, H-L; Zhao, M-W; Tang, C-M; Li, S-P

2012-09-01

To explore biocontrol potential of 39 DAEB isolates (doubly antagonistic towards both Verticillium dahliae Kleb and Fusarium oxysporum) against verticillium wilt of cotton and to elucidate colonization and category characteristics of an endophytic bacterium with significant biocontrol activity. Thirty-nine antagonistic endophytic bacteria strains were tested for their ability to control verticillium wilt in cotton plants caused by a defoliating pathotype of V. dahliae 107 in cotton under controlled conditions. The biocontrol trial revealed that an endophytic bacterium, designated HA02, showed a significant biocontrol activity to V. dahliae 107. After cotton seedlings were inoculated with a gfp gene-tagged HA02 (HA02-gfp), HA02-gfp populations were higher in the root than in the stem; in addition, the HA02-gfp was distributed in the maturation zone of cotton root. Furthermore, HA02-gfp also colonized seedlings of maize, rape and soybean after the bacteria inoculation. Phylogenetic trees based on 16S rDNA sequences combined with morphological, physiological and identification showed that the bacterium belongs to the Enterobacter genus. Our results showed that only 1 of 39 DAEB isolates demonstrated more efficient biocontrol potential towards V. dahliae 107 in greenhouse and field trials. HA02-gfp mainly colonized cotton in roots. In addition, we quantitatively observed HA02 colonization in other hosts. HA02 belongs to the Enterobacter genus. This is the first study on biocontrol to defoliating pathotype of V. dahliae Kleb by endophytic bacteria. The HA02 showed effective biocontrol to V. dahliae 107 in greenhouse and field trials. Furthermore, we assessed the quantitative and qualitative colonization of HA02 in cotton seedlings. Our study provides basic information to further explore managing strategies to control this critical disease. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Temperature variation, bacterial diversity and fungal infection dynamics in the amphibian skin.

PubMed

Longo, Ana V; Zamudio, Kelly R

2017-09-01

Host-associated bacterial communities on the skin act as the first line of defence against invading pathogens. Yet, for most natural systems, we lack a clear understanding of how temperature variability affects structure and composition of skin bacterial communities and, in turn, promotes or limits the colonization of opportunistic pathogens. Here, we examine how natural temperature fluctuations might be related to changes in skin bacterial diversity over time in three amphibian populations infected by the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Our focal host species (Eleutherodactylus coqui) is a direct-developing frog that has suffered declines at some populations in the last 20 years, while others have not experienced any changes. We quantified skin bacterial alpha- and beta-diversity at four sampling time points, a period encompassing two seasons and ample variation in natural infections and environmental conditions. Despite the different patterns of infection across populations, we detected an overall increase in bacterial diversity through time, characterized by the replacement of bacterial operational taxonomic units (OTUs). Increased frog body temperatures possibly allowed the colonization of bacteria as well as the recruitment of a subset of indicator OTUs, which could have promoted the observed changes in diversity patterns. Our results suggest that natural environmental fluctuations might be involved in creating opportunities for bacterial replacement, potentially attenuating pathogen transmission and thus contributing to host persistence in E. coqui populations. © 2017 John Wiley & Sons Ltd.

Gut Immune Maturation Depends on Colonization with a Host-Specific Microbiota

PubMed Central

Chung, Hachung; Pamp, Sünje J.; Hill, Jonathan A.; Surana, Neeraj K.; Edelman, Sanna M.; Troy, Erin B.; Reading, Nicola C.; Villablanca, Eduardo J.; Wang, Sen; Mora, Jorge R.; Umesaki, Yoshinori; Mathis, Diane; Benoist, Christophe; Relman, David A.; Kasper, Dennis L.

2012-01-01

SUMMARY Gut microbial induction of host immune maturation exemplifies host-microbe mutualism. We colonized germ-free (GF) mice with mouse microbiota (MMb) or human microbiota (HMb) to determine whether small intestinal immune maturation depends on a coevolved host-specific microbiota. Gut bacterial numbers and phylum abundance were similar in MMb and HMb mice, but bacterial species differed, especially the Firmicutes. HMb mouse intestines had low levels of CD4+ and CD8+ T cells, few proliferating T cells, few dendritic cells, and low antimicrobial peptide expression–all characteristics of GF mice. Rat microbiota also failed to fully expand intestinal T cell numbers in mice. Colonizing GF or HMb mice with mouse-segmented filamentous bacteria (SFB) partially restored T cell numbers, suggesting that SFB and other MMb organisms are required for full immune maturation in mice. Importantly, MMb conferred better protection against Salmonella infection than HMb. A host-specific microbiota appears to be critical for a healthy immune system. PMID:22726443

Clostridium difficile – From Colonization to Infection

PubMed Central

Schäffler, Holger; Breitrück, Anne

2018-01-01

Clostridium difficile is the most frequent cause of nosocomial antibiotic-associated diarrhea. The incidence of C. difficile infection (CDI) has been rising worldwide with subsequent increases in morbidity, mortality, and health care costs. Asymptomatic colonization with C. difficile is common and a high prevalence has been found in specific cohorts, e.g., hospitalized patients, adults in nursing homes and in infants. However, the risk of infection with C. difficile differs significantly between these cohorts. While CDI is a clear indication for therapy, colonization with C. difficile is not believed to be a direct precursor for CDI and therefore does not require treatment. Antibiotic therapy causes alterations of the intestinal microbial composition, enabling C. difficile colonization and consecutive toxin production leading to disruption of the colonic epithelial cells. Clinical symptoms of CDI range from mild diarrhea to potentially life-threatening conditions like pseudomembranous colitis or toxic megacolon. While antibiotics are still the treatment of choice for CDI, new therapies have emerged in recent years such as antibodies against C. difficile toxin B and fecal microbial transfer (FMT). This specific therapy for CDI underscores the role of the indigenous bacterial composition in the prevention of the disease in healthy individuals and its role in the pathogenesis after alteration by antibiotic treatment. In addition to the pathogenesis of CDI, this review focuses on the colonization of C. difficile in the human gut and factors promoting CDI. PMID:29692762

Changes in soil bacterial community structure with increasing disturbance frequency.

PubMed

Kim, Mincheol; Heo, Eunjung; Kang, Hojeong; Adams, Jonathan

2013-07-01

Little is known of the responsiveness of soil bacterial community structure to disturbance. In this study, we subjected a soil microcosm to physical disturbance, sterilizing 90 % of the soil volume each time, at a range of frequencies. We analysed the bacterial community structure using 454 pyrosequencing of the 16S rRNA gene. Bacterial diversity was found to decline with the increasing disturbance frequencies. Total bacterial abundance was, however, higher at intermediate and high disturbance frequencies, compared to low and no-disturbance treatments. Changing disturbance frequency also led to changes in community composition, with changes in overall species composition and some groups becoming abundant at the expense of others. Some phylogenetic groups were found to be relatively more disturbance-sensitive or tolerant than others. With increasing disturbance frequency, phylogenetic species variability (an index of community composition) itself became more variable from one sample to another, suggesting a greater role of chance in community composition. Compared to the tightly clustered community of the original undisturbed soil, in all the aged disturbed soils the lists of most abundant operational taxonomic units (OTUs) in each replicate were very different, suggesting a possible role of stochasticity in resource colonization and exploitation in the aged and disturbed soils. For example, colonization may be affected by whichever localized concentrations of bacterial populations happen to survive the last disturbance and be reincorporated in abundance into each pot. Overall, it appears that the soil bacterial community is very sensitive to physical disturbance, losing diversity, and that certain groups have identifiable 'high disturbance' vs. 'low disturbance' niches.

Statistical analysis of the Bacterial Carbohydrate Structure Data Base (BCSDB): Characteristics and diversity of bacterial carbohydrates in comparison with mammalian glycans

PubMed Central

Herget, Stephan; Toukach, Philip V; Ranzinger, René; Hull, William E; Knirel, Yuriy A; von der Lieth, Claus-Wilhelm

2008-01-01

Background There are considerable differences between bacterial and mammalian glycans. In contrast to most eukaryotic carbohydrates, bacterial glycans are often composed of repeating units with diverse functions ranging from structural reinforcement to adhesion, colonization and camouflage. Since bacterial glycans are typically displayed at the cell surface, they can interact with the environment and, therefore, have significant biomedical importance. Results The sequence characteristics of glycans (monosaccharide composition, modifications, and linkage patterns) for the higher bacterial taxonomic classes have been examined and compared with the data for mammals, with both similarities and unique features becoming evident. Compared to mammalian glycans, the bacterial glycans deposited in the current databases have a more than ten-fold greater diversity at the monosaccharide level, and the disaccharide pattern space is approximately nine times larger. Specific bacterial subclasses exhibit characteristic glycans which can be distinguished on the basis of distinctive structural features or sequence properties. Conclusion For the first time a systematic database analysis of the bacterial glycome has been performed. This study summarizes the current knowledge of bacterial glycan architecture and diversity and reveals putative targets for the rational design and development of therapeutic intervention strategies by comparing bacterial and mammalian glycans. PMID:18694500

Optimization of low energy sonication treatment for granular activated carbon colonizing biomass assessment.

PubMed

Saccani, G; Bernasconi, M; Antonelli, M

2014-01-01

This study is aimed at optimizing a low energy sonication (LES) treatment for granular activated carbon (GAC)-colonizing biomass detachment and determination, evaluating detachment efficiency and the effects of ultrasound exposure on bacterial cell viability. GAC samples were collected from two filters fed with groundwater. Conventional heterotrophic plate count (HPC) and fluorescence microscopy with a double staining method were used to evaluate cell viability, comparing two LES procedures, without and with periodical bulk substitution. A 20 min LES treatment, with bulk substitution after cycles of 5 min as maximum treatment time, allowed to recover 87%/100% of attached biomass, protecting detached bacteria from ultrasound damaging effects. Observed viable cell inactivation rate was 6.5/7.9% cell/min, with membrane-compromised cell damage appearing to be even higher (11.5%/13.1% cell/min). Assessing bacterial detachment and damaging ultrasound effects, fluorescence microscopy turned out to be more sensitive compared to conventional HPC. The optimized method revealed a GAC-colonizing biomass of 9.9 x 10(7) cell/gGAC for plant 1 and 8.8 x 10(7) cell/gGAC for plant 2, 2 log lower than reported in literature. The difference between the two GAC-colonizing biomasses is higher in terms of viable cells (46.3% of total cells in plant 1 GAC-colonizing biomass compared to the 33.3% in plant 2). Studying influent water contamination through multivariate statistical analyses, apossible combined toxic and genotoxic effect of chromium VI and trichloroethylene was suggested as a reason for the lower viable cell fraction observed in plant 2 GAC-colonizing population.

Rupture of abdominal aortic aneurysm into sigmoid colon: A case report

PubMed Central

Aksoy, Murat; Yanar, Hakan; Taviloglu, Korhan; Ertekin, Cemalettin; Ayalp, Kemal; Yanar, Fatih; Guloglu, Recep; Kurtoglu, Mehmet

2006-01-01

Primary aorto-colic fistula is rarely reported in the literature. Although infrequently encountered, it is an important complication since it is usually fatal unless detected. Primary aorto-colic fistula is a spontaneous rupture of abdominal aortic aneurysm into the lumen of the adjacent colon loop. Here we report a case of primary aorto-colic fistula in a 54-year old male. The fistulated sigmoid colon was repaired by end-to-end anastomosis. Despite inotropic support, the patient died of sepsis and multiorgan failure on the first postoperative day. PMID:17167850

Plasmid Dynamics in KPC-Positive Klebsiella pneumoniae during Long-Term Patient Colonization.

PubMed

Conlan, Sean; Park, Morgan; Deming, Clayton; Thomas, Pamela J; Young, Alice C; Coleman, Holly; Sison, Christina; Weingarten, Rebecca A; Lau, Anna F; Dekker, John P; Palmore, Tara N; Frank, Karen M; Segre, Julia A

2016-06-28

Carbapenem-resistant Klebsiella pneumoniae strains are formidable hospital pathogens that pose a serious threat to patients around the globe due to a rising incidence in health care facilities, high mortality rates associated with infection, and potential to spread antibiotic resistance to other bacterial species, such as Escherichia coli Over 6 months in 2011, 17 patients at the National Institutes of Health (NIH) Clinical Center became colonized with a highly virulent, transmissible carbapenem-resistant strain of K. pneumoniae Our real-time genomic sequencing tracked patient-to-patient routes of transmission and informed epidemiologists' actions to monitor and control this outbreak. Two of these patients remained colonized with carbapenemase-producing organisms for at least 2 to 4 years, providing the opportunity to undertake a focused genomic study of long-term colonization with antibiotic-resistant bacteria. Whole-genome sequencing studies shed light on the underlying complex microbial colonization, including mixed or evolving bacterial populations and gain or loss of plasmids. Isolates from NIH patient 15 showed complex plasmid rearrangements, leaving the chromosome and the blaKPC-carrying plasmid intact but rearranging the two other plasmids of this outbreak strain. NIH patient 16 has shown continuous colonization with blaKPC-positive organisms across multiple time points spanning 2011 to 2015. Genomic studies defined a complex pattern of succession and plasmid transmission across two different K. pneumoniae sequence types and an E. coli isolate. These findings demonstrate the utility of genomic methods for understanding strain succession, genome plasticity, and long-term carriage of antibiotic-resistant organisms. In 2011, the NIH Clinical Center had a nosocomial outbreak involving 19 patients who became colonized or infected with blaKPC-positive Klebsiella pneumoniae Patients who have intestinal colonization with blaKPC-positive K. pneumoniae are at

Bacteria are not the primary cause of bleaching in the Mediterranean coral Oculina patagonica.

PubMed

Ainsworth, T D; Fine, M; Roff, G; Hoegh-Guldberg, O

2008-01-01

Coral bleaching occurs when the endosymbiosis between corals and their symbionts disintegrates during stress. Mass coral bleaching events have increased over the past 20 years and are directly correlated with periods of warm sea temperatures. However, some hypotheses have suggested that reef-building corals bleach due to infection by bacterial pathogens. The 'Bacterial Bleaching' hypothesis is based on laboratory studies of the Mediterranean invading coral, Oculina patagonica, and has further generated conclusions such as the coral probiotic hypothesis and coral hologenome theory of evolution. We aimed to investigate the natural microbial ecology of O. patagonica during the annual bleaching using fluorescence in situ hybridization to map bacterial populations within the coral tissue layers, and found that the coral bleaches on the temperate rocky reefs of the Israeli coastline without the presence of Vibrio shiloi or bacterial penetration of its tissue layers. Bacterial communities were found associated with the endolithic layer of bleached coral regions, and a community dominance shift from an apparent cyanobacterial-dominated endolithic layer to an algal-dominated layer was found in bleached coral samples. While bacterial communities certainly play important roles in coral stasis and health, we suggest environmental stressors, such as those documented with reef-building corals, are the primary triggers leading to bleaching of O. patagonica and suggest that bacterial involvement in patterns of bleaching is that of opportunistic colonization.

Case Study of the Distribution of Mucosa-Associated Bifidobacterium Species, Lactobacillus Species, and Other Lactic Acid Bacteria in the Human Colon

PubMed Central

Nielsen, D. S.; Møller, P. L.; Rosenfeldt, V.; Pærregaard, A.; Michaelsen, K. F.; Jakobsen, M.

2003-01-01

The distribution of mucosa-associated bacteria, bifidobacteria and lactobacilli and closely related lactic acid bacteria, in biopsy samples from the ascending, transverse, and descending parts of the colon from four individuals was investigated by denaturing gradient gel electrophoresis (DGGE). Bifidobacterial genus-specific, Lactobacillus group-specific, and universal bacterial primers were used in a nested PCR approach to amplify a fragment of the 16S rRNA gene. DGGE profiles of the bifidobacterial community were relatively simple, with one or two amplicons detected at most sampling sites in the colon. DGGE profiles obtained with Lactobacillus group-specific primers were complex and varied with host and sampling site in the colon. The overall bacterial community varied with host but not sampling site. PMID:14660412

A study of the pattern, management and outcome of penetrating colon injuries in Sagamu.

PubMed

Tade, A O; Thanni, L O A; Ayoade, B A

2009-09-01

Colon injuries are increasingly being treated safely by primary repair in spite of the high risk of septic complications. This is a retrospective study of the pattern, management and outcome in patients treated for penetrating colon injuries at Olabisi Onabanjo University Teaching Hospital, Sagamu over a 7 year period (January 1995-December 2001). Records of thirty-two patients were studied. Gunshots (75 percent) and knife stabs (18.75 percent) accounted for ninety-four percent of penetrating colon injuries. Associated intra-abdominal injuries were present in 22 patients (68.8 percent). Eight (twenty-five percent) patients presented in shock. Moderate to major faecal contamination was present in 30 (93.8%) patients. Severe colon injury occurred in nine patients. The eighteen patients with right colon wounds were managed by primary repair. All the fourteen patients with left colon wounds had a diverting colostomy alongside repair or resection. Complications included wound infection (56.7 percent) and septicaemia (31.7 percent). Eleven patients died, giving an overall mortality rate of 34.4 percent. Mortality was significantly associated with shock on admission (p<0.02), degree of faecal contamination (p<0.05) and severity of colon injury (p<0.01). Colostomy did not affect mortality. (P<0.1). In this study primary repair was employed in 56% of patients with penetrating colon injuries. The routine use of diverting colostomy for all left colon injuries can no longer be justified in current surgical practice as colostomy did not affect mortality.

The features of mucosa-associated microbiota in primary sclerosing cholangitis.

PubMed

Torres, J; Bao, X; Goel, A; Colombel, J-F; Pekow, J; Jabri, B; Williams, K M; Castillo, A; Odin, J A; Meckel, K; Fasihuddin, F; Peter, I; Itzkowitz, S; Hu, J

2016-04-01

Little is known about the role of the microbiome in primary sclerosing cholangitis. To explore the mucosa-associated microbiota in primary sclerosing cholangitis (PSC) patients across different locations in the gut, and to compare it with inflammatory bowel disease (IBD)-only patients and healthy controls. Biopsies from the terminal ileum, right colon, and left colon were collected from patients and healthy controls undergoing colonoscopy. Microbiota profiling using bacterial 16S rRNA sequencing was performed on all biopsies. Forty-four patients were recruited: 20 with PSC (19 with PSC-IBD and one with PSC-only), 15 with IBD-only and nine healthy controls. The overall microbiome profile was similar throughout different locations in the gut. No differences in the global microbiome profile were found. However, we observed significant PSC-associated enrichment in Barnesiellaceae at the family level, and in Blautia and an unidentified Barnesiellaceae at the genus level. At the operational taxa unit level, most shifts in PSC were observed in Clostridiales and Bacteroidales orders, with approximately 86% of shifts occurring within the former order. The overall microbiota profile was similar across multiple locations in the gut from the same individual regardless of disease status. In this study, the mucosa associated-microbiota of patients with primary sclerosing cholangitis was characterised by enrichment of Blautia and Barnesiellaceae and by major shifts in operational taxa units within Clostridiales order. © 2016 John Wiley & Sons Ltd.

A new mathematical model of bacterial interactions in two-species oral biofilms

PubMed Central

Martin, Bénédicte; Tamanai-Shacoori, Zohreh; Bronsard, Julie; Ginguené, Franck; Meuric, Vincent

2017-01-01

Periodontitis are bacterial inflammatory diseases, where the bacterial biofilms present on the tooth-supporting tissues switch from a healthy state towards a pathogenic state. Among bacterial species involved in the disease, Porphyromonas gingivalis has been shown to induce dysbiosis, and to induce virulence of otherwise healthy bacteria like Streptococcus gordonii. During biofilm development, primary colonizers such as S. gordonii first attach to the surface and allow the subsequent adhesion of periodontal pathogens such as P. gingivalis. Interactions between those two bacteria have been extensively studied during the adhesion step of the biofilm. The aim of the study was to understand interactions of both species during the growing phase of the biofilm, for which little knowledge is available, using a mathematical model. This two-species biofilm model was based on a substrate-dependent growth, implemented with damage parameters, and validated thanks to data obtained on experimental biofilms. Three different hypothesis of interactions were proposed and assayed using this model: independence, competition between both bacteria species, or induction of toxicity by one species for the other species. Adequacy between experimental and simulated biofilms were found with the last hypothetic mathematical model. This new mathematical model of two species bacteria biofilms, dependent on different substrates for growing, can be applied to any bacteria species, environmental conditions, or steps of biofilm development. It will be of great interest for exploring bacterial interactions in biofilm conditions. PMID:28253369

Bacteria from diverse habitats colonize and compete in the mouse gut.

PubMed

Seedorf, Henning; Griffin, Nicholas W; Ridaura, Vanessa K; Reyes, Alejandro; Cheng, Jiye; Rey, Federico E; Smith, Michelle I; Simon, Gabriel M; Scheffrahn, Rudolf H; Woebken, Dagmar; Spormann, Alfred M; Van Treuren, William; Ursell, Luke K; Pirrung, Megan; Robbins-Pianka, Adam; Cantarel, Brandi L; Lombard, Vincent; Henrissat, Bernard; Knight, Rob; Gordon, Jeffrey I

2014-10-09

To study how microbes establish themselves in a mammalian gut environment, we colonized germ-free mice with microbial communities from human, zebrafish, and termite guts, human skin and tongue, soil, and estuarine microbial mats. Bacteria from these foreign environments colonized and persisted in the mouse gut; their capacity to metabolize dietary and host carbohydrates and bile acids correlated with colonization success. Cohousing mice harboring these xenomicrobiota or a mouse cecal microbiota, along with germ-free "bystanders," revealed the success of particular bacterial taxa in invading guts with established communities and empty gut habitats. Unanticipated patterns of ecological succession were observed; for example, a soil-derived bacterium dominated even in the presence of bacteria from other gut communities (zebrafish and termite), and human-derived bacteria colonized germ-free bystander mice before mouse-derived organisms. This approach can be generalized to address a variety of mechanistic questions about succession, including succession in the context of microbiota-directed therapeutics. Copyright © 2014 Elsevier Inc. All rights reserved.

Multiple Acid Sensors Control Helicobacter pylori Colonization of the Stomach.

PubMed

Huang, Julie Y; Goers Sweeney, Emily; Guillemin, Karen; Amieva, Manuel R

2017-01-01

Helicobacter pylori's ability to respond to environmental cues in the stomach is integral to its survival. By directly visualizing H. pylori swimming behavior when encountering a microscopic gradient consisting of the repellent acid and attractant urea, we found that H. pylori is able to simultaneously detect both signals, and its response depends on the magnitudes of the individual signals. By testing for the bacteria's response to a pure acid gradient, we discovered that the chemoreceptors TlpA and TlpD are each independent acid sensors. They enable H. pylori to respond to and escape from increases in hydrogen ion concentration near 100 nanomolar. TlpD also mediates attraction to basic pH, a response dampened by another chemoreceptor TlpB. H. pylori mutants lacking both TlpA and TlpD (ΔtlpAD) are unable to sense acid and are defective in establishing colonization in the murine stomach. However, blocking acid production in the stomach with omeprazole rescues ΔtlpAD's colonization defect. We used 3D confocal microscopy to determine how acid blockade affects the distribution of H. pylori in the stomach. We found that stomach acid controls not only the overall bacterial density, but also the microscopic distribution of bacteria that colonize the epithelium deep in the gastric glands. In omeprazole treated animals, bacterial abundance is increased in the antral glands, and gland colonization range is extended to the corpus. Our findings indicate that H. pylori has evolved at least two independent receptors capable of detecting acid gradients, allowing not only survival in the stomach, but also controlling the interaction of the bacteria with the epithelium.

Multiple Acid Sensors Control Helicobacter pylori Colonization of the Stomach

PubMed Central

Huang, Julie Y.; Goers Sweeney, Emily; Guillemin, Karen

2017-01-01

Helicobacter pylori’s ability to respond to environmental cues in the stomach is integral to its survival. By directly visualizing H. pylori swimming behavior when encountering a microscopic gradient consisting of the repellent acid and attractant urea, we found that H. pylori is able to simultaneously detect both signals, and its response depends on the magnitudes of the individual signals. By testing for the bacteria’s response to a pure acid gradient, we discovered that the chemoreceptors TlpA and TlpD are each independent acid sensors. They enable H. pylori to respond to and escape from increases in hydrogen ion concentration near 100 nanomolar. TlpD also mediates attraction to basic pH, a response dampened by another chemoreceptor TlpB. H. pylori mutants lacking both TlpA and TlpD (ΔtlpAD) are unable to sense acid and are defective in establishing colonization in the murine stomach. However, blocking acid production in the stomach with omeprazole rescues ΔtlpAD’s colonization defect. We used 3D confocal microscopy to determine how acid blockade affects the distribution of H. pylori in the stomach. We found that stomach acid controls not only the overall bacterial density, but also the microscopic distribution of bacteria that colonize the epithelium deep in the gastric glands. In omeprazole treated animals, bacterial abundance is increased in the antral glands, and gland colonization range is extended to the corpus. Our findings indicate that H. pylori has evolved at least two independent receptors capable of detecting acid gradients, allowing not only survival in the stomach, but also controlling the interaction of the bacteria with the epithelium. PMID:28103315

Ursodeoxycholic acid attenuates colonic epithelial secretory function

PubMed Central

Kelly, Orlaith B; Mroz, Magdalena S; Ward, Joseph B J; Colliva, Carolina; Scharl, Michael; Pellicciari, Roberto; Gilmer, John F; Fallon, Padraic G; Hofmann, Alan F; Roda, Aldo; Murray, Frank E; Keely, Stephen J

2013-01-01

Dihydroxy bile acids, such as chenodeoxycholic acid (CDCA), are well known to promote colonic fluid and electrolyte secretion, thereby causing diarrhoea associated with bile acid malabsorption. However, CDCA is rapidly metabolised by colonic bacteria to ursodeoxycholic acid (UDCA), the effects of which on epithelial transport are poorly characterised. Here, we investigated the role of UDCA in the regulation of colonic epithelial secretion. Cl− secretion was measured across voltage-clamped monolayers of T84 cells and muscle-stripped sections of mouse or human colon. Cell surface biotinylation was used to assess abundance/surface expression of transport proteins. Acute (15 min) treatment of T84 cells with bilateral UDCA attenuated Cl− secretory responses to the Ca2+ and cAMP-dependent secretagogues carbachol (CCh) and forskolin (FSK) to 14.0 ± 3.8 and 40.2 ± 7.4% of controls, respectively (n= 18, P < 0.001). Investigation of the molecular targets involved revealed that UDCA acts by inhibiting Na+/K+-ATPase activity and basolateral K+ channel currents, without altering their cell surface expression. In contrast, intraperitoneal administration of UDCA (25 mg kg−1) to mice enhanced agonist-induced colonic secretory responses, an effect we hypothesised to be due to bacterial metabolism of UDCA to lithocholic acid (LCA). Accordingly, LCA (50–200 μm) enhanced agonist-induced secretory responses in vitro and a metabolically stable UDCA analogue, 6α-methyl-UDCA, exerted anti-secretory actions in vitro and in vivo. In conclusion, UDCA exerts direct anti-secretory actions on colonic epithelial cells and metabolically stable derivatives of the bile acid may offer a new approach for treating intestinal diseases associated with diarrhoea. PMID:23507881

Step-Wise Loss of Bacterial Flagellar Torsion Confers Progressive Phagocytic Evasion

PubMed Central

Lovewell, Rustin R.; Collins, Ryan M.; Acker, Julie L.; O'Toole, George A.; Wargo, Matthew J.; Berwin, Brent

2011-01-01

Phagocytosis of bacteria by innate immune cells is a primary method of bacterial clearance during infection. However, the mechanisms by which the host cell recognizes bacteria and consequentially initiates phagocytosis are largely unclear. Previous studies of the bacterium Pseudomonas aeruginosa have indicated that bacterial flagella and flagellar motility play an important role in colonization of the host and, importantly, that loss of flagellar motility enables phagocytic evasion. Here we use molecular, cellular, and genetic methods to provide the first formal evidence that phagocytic cells recognize bacterial motility rather than flagella and initiate phagocytosis in response to this motility. We demonstrate that deletion of genes coding for the flagellar stator complex, which results in non-swimming bacteria that retain an initial flagellar structure, confers resistance to phagocytic binding and ingestion in several species of the gamma proteobacterial group of Gram-negative bacteria, indicative of a shared strategy for phagocytic evasion. Furthermore, we show for the first time that susceptibility to phagocytosis in swimming bacteria is proportional to mot gene function and, consequently, flagellar rotation since complementary genetically- and biochemically-modulated incremental decreases in flagellar motility result in corresponding and proportional phagocytic evasion. These findings identify that phagocytic cells respond to flagellar movement, which represents a novel mechanism for non-opsonized phagocytic recognition of pathogenic bacteria. PMID:21949654

Nasopharyngeal colonization by potentially pathogenic bacteria found in healthy semi-captive wild-born chimpanzees in Uganda.

PubMed

Mugisha, Lawrence; Köndgen, Sophie; Kaddu-Mulindwa, Deogratias; Gaffikin, Lynne; Leendertz, Fabian H

2014-02-01

Information on the chimpanzee nasopharygeal colonization in captive sanctuaries and in the wild is rare. This study was undertaken to establish the nasopharygeal colonization and potential bacterial pathogens in sanctuary chimpanzees as a basis for improving chimpanzee and employee health. Nasopharygeal colonization of 39 healthy chimpanzees were analyzed by microbiological cultivation method and polymerase chain reaction (PCR) targeting the bacterial 16S rRNA gene. We report four major phyla dominated by Proteobacteria (50%), Fermicutes (35.7%), Bacteriodes (7.1%), and Cynobacteria (7.1%) in healthy semi-captive chimpanzees. Further classification based on 7-base oligomers revealed the following genera: Streptococcus, Veillonella, Neisseria, Prevotella, Kingella and unclassified Cynobacteria, Actinobacillus, Bacteriodes and Pasteurellaceae. On microbiological cultivation we were able to identify and characterize some of the bacteria to species level as Klebsiella pneumonie and Pseudomonas aeruginosa being dominant bacteria with 54.7% and 50% colonization, respectively. Of these, Streptococcus, Neisseria, Klebsiella, and Haemophillus have representatives known to potentially cause severe respiratory disease. Our data present important information on chimpanzee nasopharygeal colonization as a guide to understanding disease processes and pharmaceutical therapies required for improving the health of chimpanzees. The results from this study will guide the processes to improve procedures for routine management of sanctuary chimpanzees and use it as a basis for evaluation of future reintroduction possibilities. © 2013 Wiley Periodicals, Inc.

Applicability of an established management algorithm for colon injuries following blunt trauma.

PubMed

Sharpe, John P; Magnotti, Louis J; Weinberg, Jordan A; Shahan, Charles P; Cullinan, Darren R; Fabian, Timothy C; Croce, Martin A

2013-02-01

Operative management at our institution for all colon injuries have followed a defined algorithm (ALG) based on risk factors originally identified for penetrating injuries. The purpose of this study was to evaluate the applicability of the ALG to blunt colon injuries. Patients with blunt colon injuries during 13 years were identified. As per the ALG, nondestructive (ND) injuries are treated with primary repair. Patients with destructive wounds (serosal tear of ≥50% colon circumference, mesenteric devascularization, and perforations) and concomitant risk factors (transfusion of >6 U packed red blood cells and/or presence of significant comorbidities) are diverted, while patients with no risk factors undergo resection plus anastomosis (RA). Outcomes included suture line failure (SLF), abscess, and mortality. Stratification analysis was performed to determine additional risk factors in the management of blunt colon injuries. A total 151 patients were identified: 76 with destructive injuries and 75 with ND injuries. Of those with destructive injuries, 44 (59%) underwent RA and 29 (39%) underwent diversion. All ND injuries underwent primary repair. Adherence to the ALG was 95%: three patients with destructive injuries underwent primary repair, and five patients with risk factors underwent RA. There were three SLFs (2%) (one involved deviation from the ALG) and eight abscesses (5%). Colon-related mortality was 2.1%. Stratification analysis based on mesenteric involvement, degree of shock, and need for abbreviated laparotomy failed to identify additional risk factors for SLF following RA for blunt colon injuries. Adherence to an ALG, originally defined for penetrating colon injuries, simplified the management of blunt colon injuries. ND injuries should be primarily repaired. For destructive wounds, management based on a defined ALG achieves an acceptably low morbidity and mortality rate. Prognostic/epidemiologic study, level III; therapeutic study, level IV.

Bacterial Diets of Primary Consumers at Hydrothermal Vents

NASA Astrophysics Data System (ADS)

Govenar, B.; Shank, T. M.

2008-12-01

Chemical energy produced by mixing hydrothermal fluids and seawater supports dense biological communities on mid-ocean ridges. The base of the food web at deep-sea hydrothermal vents is formed by chemolithoautotrophic bacteria that use the energy from the oxidation of reduced chemicals to fix inorganic carbon into simple sugars. With the exception of a few species that have chemolithoautotropic bacterial symbionts, most of the vent-endemic macrofauna are heterotrophs that feed on free-living bacteria, protists, and other invertebrates. The most abundant and diverse group of primary consumers in hydrothermal vent communities belong to the Gastropoda, particularly the patellomorph limpets. Gastropod densities can be as high as 2000 individuals m-2, and there can be as many as 13 species of gastropods in a single aggregation of the siboglinid tubeworm Riftia pachyptila and more than 40 species along the East Pacific Rise. Some gastropods are ubiquitous and others are found in specific microhabitats, stages of succession, or associated with different foundation species. To determine the mechanisms of species coexistence (e.g. resource partitioning or competition) among hydrothermal vent primary consumers and to track the flow of energy in hydrothermal vent communities, we employed molecular genetic techniques to identify the gut contents of four species of co-occurring hydrothermal vent gastropods, Eulepetopsis vitrea, Lepetodrilus elevatus, Lepetodrilus ovalis and Lepetodrilus pustulosus, collected from a single diffuse-flow hydrothermal vent site on the East Pacific Rise. Unique haplotypes of the 16S gene that fell among the epsilon-proteobacteria were found in the guts of every species, and two species had gut contents that were similar only to epsilon-proteobacteria. Two species had gut contents that also included haplotypes that clustered with delta-proteobacteria, and one species had gut contents that clustered with alpha- proteobacteria. Differences in the diets

Motility and Chemotaxis Mediate the Preferential Colonization of Gastric Injury Sites by Helicobacter pylori

PubMed Central

Aihara, Eitaro; Closson, Chet; Matthis, Andrea L.; Schumacher, Michael A.; Engevik, Amy C.; Zavros, Yana; Ottemann, Karen M.; Montrose, Marshall H.

2014-01-01

Helicobacter pylori (H. pylori) is a pathogen contributing to peptic inflammation, ulceration, and cancer. A crucial step in the pathogenic sequence is when the bacterium first interacts with gastric tissue, an event that is poorly understood in vivo. We have shown that the luminal space adjacent to gastric epithelial damage is a microenvironment, and we hypothesized that this microenvironment might enhance H. pylori colonization. Inoculation with 106 H. pylori (wild-type Sydney Strain 1, SS1) significantly delayed healing of acetic-acid induced ulcers at Day 1, 7 and 30 post-inoculation, and wild-type SS1 preferentially colonized the ulcerated area compared to uninjured gastric tissue in the same animal at all time points. Gastric resident Lactobacillus spp. did not preferentially colonize ulcerated tissue. To determine whether bacterial motility and chemotaxis are important to ulcer healing and colonization, we analyzed isogenic H. pylori mutants defective in motility (ΔmotB) or chemotaxis (ΔcheY). ΔmotB (106) failed to colonize ulcerated or healthy stomach tissue. ΔcheY (106) colonized both tissues, but without preferential colonization of ulcerated tissue. However, ΔcheY did modestly delay ulcer healing, suggesting that chemotaxis is not required for this process. We used two-photon microscopy to induce microscopic epithelial lesions in vivo, and evaluated accumulation of fluorescently labeled H. pylori at gastric damage sites in the time frame of minutes instead of days. By 5 min after inducing damage, H. pylori SS1 preferentially accumulated at the site of damage and inhibited gastric epithelial restitution. H. pylori ΔcheY modestly accumulated at the gastric surface and inhibited restitution, but did not preferentially accumulate at the injury site. H. pylori ΔmotB neither accumulated at the surface nor inhibited restitution. We conclude that bacterial chemosensing and motility rapidly promote H. pylori colonization of injury sites, and thereby biases

Motility and chemotaxis mediate the preferential colonization of gastric injury sites by Helicobacter pylori.

PubMed

Aihara, Eitaro; Closson, Chet; Matthis, Andrea L; Schumacher, Michael A; Engevik, Amy C; Zavros, Yana; Ottemann, Karen M; Montrose, Marshall H

2014-07-01

Helicobacter pylori (H. pylori) is a pathogen contributing to peptic inflammation, ulceration, and cancer. A crucial step in the pathogenic sequence is when the bacterium first interacts with gastric tissue, an event that is poorly understood in vivo. We have shown that the luminal space adjacent to gastric epithelial damage is a microenvironment, and we hypothesized that this microenvironment might enhance H. pylori colonization. Inoculation with 106 H. pylori (wild-type Sydney Strain 1, SS1) significantly delayed healing of acetic-acid induced ulcers at Day 1, 7 and 30 post-inoculation, and wild-type SS1 preferentially colonized the ulcerated area compared to uninjured gastric tissue in the same animal at all time points. Gastric resident Lactobacillus spp. did not preferentially colonize ulcerated tissue. To determine whether bacterial motility and chemotaxis are important to ulcer healing and colonization, we analyzed isogenic H. pylori mutants defective in motility (ΔmotB) or chemotaxis (ΔcheY). ΔmotB (10(6)) failed to colonize ulcerated or healthy stomach tissue. ΔcheY (10(6)) colonized both tissues, but without preferential colonization of ulcerated tissue. However, ΔcheY did modestly delay ulcer healing, suggesting that chemotaxis is not required for this process. We used two-photon microscopy to induce microscopic epithelial lesions in vivo, and evaluated accumulation of fluorescently labeled H. pylori at gastric damage sites in the time frame of minutes instead of days. By 5 min after inducing damage, H. pylori SS1 preferentially accumulated at the site of damage and inhibited gastric epithelial restitution. H. pylori ΔcheY modestly accumulated at the gastric surface and inhibited restitution, but did not preferentially accumulate at the injury site. H. pylori ΔmotB neither accumulated at the surface nor inhibited restitution. We conclude that bacterial chemosensing and motility rapidly promote H. pylori colonization of injury sites, and thereby

Evolution of the operative management of colon trauma

PubMed Central

Sharpe, John P; Magnotti, Louis J; Fabian, Timothy C; Croce, Martin A

2017-01-01

For any trauma surgeon, colon wounds remain a relatively common, yet sometimes challenging, clinical problem. Evolution in operative technique and improvements in antimicrobial therapy during the past two centuries have brought remarkable improvements in both morbidity and mortality after injury to the colon. Much of the early progress in management and patient survival after colon trauma evolved from wartime experience. Multiple evidence-based studies during the last several decades have allowed for more aggressive management, with most wounds undergoing primary repair or resection and anastomosis with an acceptably low suture line failure rate. Despite the abundance of quality evidence regarding management of colon trauma obtained from both military and civilian experience, there remains some debate among institutions regarding management of specific injuries. This is especially true with respect to destructive wounds, injuries to the left colon, blunt colon trauma and those wounds requiring colonic discontinuity during an abbreviated laparotomy. Some programs have developed data-driven protocols that have simplified management of destructive colon wounds, clearly identifying those high-risk patients who should undergo diversion, regardless of mechanism or anatomic location. This update will describe the progression in the approach to colon injuries through history while providing a current review of the literature regarding management of the more controversial wounds.

Evolution of the operative management of colon trauma.

PubMed

Sharpe, John P; Magnotti, Louis J; Fabian, Timothy C; Croce, Martin A

2017-01-01

For any trauma surgeon, colon wounds remain a relatively common, yet sometimes challenging, clinical problem. Evolution in operative technique and improvements in antimicrobial therapy during the past two centuries have brought remarkable improvements in both morbidity and mortality after injury to the colon. Much of the early progress in management and patient survival after colon trauma evolved from wartime experience. Multiple evidence-based studies during the last several decades have allowed for more aggressive management, with most wounds undergoing primary repair or resection and anastomosis with an acceptably low suture line failure rate. Despite the abundance of quality evidence regarding management of colon trauma obtained from both military and civilian experience, there remains some debate among institutions regarding management of specific injuries. This is especially true with respect to destructive wounds, injuries to the left colon, blunt colon trauma and those wounds requiring colonic discontinuity during an abbreviated laparotomy. Some programs have developed data-driven protocols that have simplified management of destructive colon wounds, clearly identifying those high-risk patients who should undergo diversion, regardless of mechanism or anatomic location. This update will describe the progression in the approach to colon injuries through history while providing a current review of the literature regarding management of the more controversial wounds.

The Role of Curcumin in Modulating Colonic Microbiota During Colitis and Colon Cancer Prevention.

PubMed

McFadden, Rita-Marie T; Larmonier, Claire B; Shehab, Kareem W; Midura-Kiela, Monica; Ramalingam, Rajalakshmy; Harrison, Christy A; Besselsen, David G; Chase, John H; Caporaso, J Gregory; Jobin, Christian; Ghishan, Fayez K; Kiela, Pawel R

2015-11-01

Intestinal microbiota influences the progression of colitis-associated colorectal cancer. With diet being a key determinant of the gut microbial ecology, dietary interventions are an attractive avenue for the prevention of colitis-associated colorectal cancer. Curcumin is the most active constituent of the ground rhizome of the Curcuma longa plant, which has been demonstrated to have anti-inflammatory, antioxidative, and antiproliferative properties. Il10 mice on 129/SvEv background were used as a model of colitis-associated colorectal cancer. Starting at 10 weeks of age, wild-type or Il10 mice received 6 weekly intraperitoneal injections of azoxymethane (AOM) or phosphate-buffered saline (PBS) and were started on either a control or a curcumin-supplemented diet. Stools were collected every 4 weeks for microbial community analysis. Mice were killed at 30 weeks of age. Curcumin-supplemented diet increased survival, decreased colon weight/length ratio, and, at 0.5%, entirely eliminated tumor burden. Although colonic histology indicated improvement with curcumin, no effects of mucosal immune responses have been observed in PBS/Il10 mice and limited effects were seen in AOM/Il10 mice. In wild-type and in Il10 mice, curcumin increased bacterial richness, prevented age-related decrease in alpha diversity, increased the relative abundance of Lactobacillales, and decreased Coriobacterales order. Taxonomic profile of AOM/Il10 mice receiving curcumin was more similar to those of wild-type mice than those fed control diet. In AOM/Il10 model, curcumin reduced or eliminated colonic tumor burden with limited effects on mucosal immune responses. The beneficial effect of curcumin on tumorigenesis was associated with the maintenance of a more diverse colonic microbial ecology.

[Original strategy for prevention of recurrent symptomatic urinary tract infections in patients with neurogenic bladder: Bacterial interference, state of the art].

PubMed

Falcou, L; Davido, B; Even, A; Bouchand, F; Salomon, J; Sotto, A; Denys, P; Dinh, A

2018-05-01

Urinary tract infection (UTI) is the most common complication in patients with neurogenic bladder. The long-term use of antibiotic drugs induces an increase in antimicrobial resistance and adverse drug reactions. Bacterial interference is a new concept to prevent recurrent UTI which consists in a bladder colonization with low virulence bacteria. We performed a literature review on this emerging therapy. Literature review of bacterial interference to prevent symptomatic urinary tract infection in neurological population. Seven prospectives study including 3 randomized, double-blind and placebo controlled trial were analyzed. The neurological population was spinal cord injured in most cases. The bladder colonization was performed with 2 non-pathogen strains of Escherichia coli: HU 2117 and 83972. At 1 month, 38 to 83% of patients were colonized. Mean duration of colonization was 48.5 days to 12.3 months. All studies showed that colonization might reduce the number of urinary tract infections and is safe with absence of serious side effects. Bacterial interference is a promising alternative therapy for the prevention of recurrent symptomatic urinary tract infections in neurogenic patients. This therapy should have developments for a daily use practice and for a long-term efficacy. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Bacterial contamination hypothesis: a new concept in endometriosis.

PubMed

Khan, Khaleque N; Fujishita, Akira; Hiraki, Koichi; Kitajima, Michio; Nakashima, Masahiro; Fushiki, Shinji; Kitawaki, Jo

2018-04-01

Endometriosis is a multifactorial disease that mainly affects women of reproductive age. The exact pathogenesis of this disease is still debatable. The role of bacterial endotoxin (lipopolysaccharide, LPS) and Toll-like receptor 4 (TLR4) in endometriosis were investigated and the possible source of endotoxin in the pelvic environment was examined. The limulus amoebocyte lysate test was used to measure the endotoxin levels in the menstrual fluid and peritoneal fluid and their potential role in the growth of endometriosis was investigated. Menstrual blood and endometrial samples were cultured for the presence of microbes. The effect of gonadotrophin-releasing hormone agonist (GnRHa) treatment on intrauterine microbial colonization (IUMC) and the occurrence of endometritis was investigated. Lipopolysaccharide regulates the pro-inflammatory response in the pelvis and growth of endometriosis via the LPS/TLR4 cascade. The menstrual blood was highly contaminated with Escherichea coli and the endometrial samples were colonized with other microbes. A cross-talk between inflammation and ovarian steroids or the stress reaction also was observed in the pelvis. Treatment with GnRHa further worsens intrauterine microbial colonization, with the consequent occurrence of endometritis in women with endometriosis. For the first time, a new concept called the "bacterial contamination hypothesis" is proposed in endometriosis. This study's findings of IUMC in women with endometriosis could hold new therapeutic potential in addition to the conventional estrogen-suppressing agent.

O Antigen Modulates Insect Vector Acquisition of the Bacterial Plant Pathogen Xylella fastidiosa

PubMed Central

Rapicavoli, Jeannette N.; Kinsinger, Nichola; Perring, Thomas M.; Backus, Elaine A.; Shugart, Holly J.; Walker, Sharon

2015-01-01

Hemipteran insect vectors transmit the majority of plant pathogens. Acquisition of pathogenic bacteria by these piercing/sucking insects requires intimate associations between the bacterial cells and insect surfaces. Lipopolysaccharide (LPS) is the predominant macromolecule displayed on the cell surface of Gram-negative bacteria and thus mediates bacterial interactions with the environment and potential hosts. We hypothesized that bacterial cell surface properties mediated by LPS would be important in modulating vector-pathogen interactions required for acquisition of the bacterial plant pathogen Xylella fastidiosa, the causative agent of Pierce's disease of grapevines. Utilizing a mutant that produces truncated O antigen (the terminal portion of the LPS molecule), we present results that link this LPS structural alteration to a significant decrease in the attachment of X. fastidiosa to blue-green sharpshooter foreguts. Scanning electron microscopy confirmed that this defect in initial attachment compromised subsequent biofilm formation within vector foreguts, thus impairing pathogen acquisition. We also establish a relationship between O antigen truncation and significant changes in the physiochemical properties of the cell, which in turn affect the dynamics of X. fastidiosa adhesion to the vector foregut. Lastly, we couple measurements of the physiochemical properties of the cell with hydrodynamic fluid shear rates to produce a Comsol model that predicts primary areas of bacterial colonization within blue-green sharpshooter foreguts, and we present experimental data that support the model. These results demonstrate that, in addition to reported protein adhesin-ligand interactions, O antigen is crucial for vector-pathogen interactions, specifically in the acquisition of this destructive agricultural pathogen. PMID:26386068

Effect of Pre-weaning Diet on the Ruminal Archaeal, Bacterial, and Fungal Communities of Dairy Calves

PubMed Central

Dias, Juliana; Marcondes, Marcos I.; Noronha, Melline F.; Resende, Rafael T.; Machado, Fernanda S.; Mantovani, Hilário C.; Dill-McFarland, Kimberly A.; Suen, Garret

2017-01-01

At birth, calves display an underdeveloped rumen that eventually matures into a fully functional rumen as a result of solid food intake and microbial activity. However, little is known regarding the gradual impact of pre-weaning diet on the establishment of the rumen microbiota. Here, we employed next-generation sequencing to investigate the effects of the inclusion of starter concentrate (M: milk-fed vs. MC: milk plus starter concentrate fed) on archaeal, bacterial and anaerobic fungal communities in the rumens of 45 crossbred dairy calves across pre-weaning development (7, 28, 49, and 63 days). Our results show that archaeal, bacterial, and fungal taxa commonly found in the mature rumen were already established in the rumens of calves at 7 days old, regardless of diet. This confirms that microbiota colonization occurs in the absence of solid substrate. However, diet did significantly impact some microbial taxa. In the bacterial community, feeding starter concentrate promoted greater diversity of bacterial taxa known to degrade readily fermentable carbohydrates in the rumen (e.g., Megasphaera, Sharpea, and Succinivribrio). Shifts in the ruminal bacterial community also correlated to changes in fermentation patterns that favored the colonization of Methanosphaera sp. A4 in the rumen of MC calves. In contrast, M calves displayed a bacterial community dominated by taxa able to utilize milk nutrients (e.g., Lactobacillus, Bacteroides, and Parabacteroides). In both diet groups, the dominance of these milk-associated taxa decreased with age, suggesting that diet and age simultaneously drive changes in the structure and abundance of bacterial communities in the developing rumen. Changes in the composition and abundance of archaeal communities were attributed exclusively to diet, with more highly abundant Methanosphaera and less abundant Methanobrevibacter in MC calves. Finally, the fungal community was dominated by members of the genus SK3 and Caecomyces. Relative

Colonization of fish skin is vital for Vibrio anguillarum to cause disease.

PubMed

Weber, Barbara; Chen, Chang; Milton, Debra L

2010-02-01

Vibrio anguillarum causes a fatal haemorrhagic septicaemia in marine fish. During initial stages of infection, host surfaces are colonized; however, few virulence factors required for colonization of the host are identified. In this study, in vivo bioluminescent imaging was used to analyse directly the colonization of the whole rainbow trout animal by V. anguillarum. The wild type rapidly colonized both the skin and the intestines by 24 h; however, the bacterial numbers on the skin were significantly higher than in the intestines indicating that skin colonization may be important for disease to occur. Mutants defective for the anguibactin iron uptake system, exopolysaccharide transport, or Hfq, an RNA chaperone, were attenuated for virulence, did not colonize the skin, and penetrated skin mucus less efficiently than the wild type. These mutants, however, did colonize the intestines and were as resistant to 2% bile salts as is the wild type. Moreover, exopolysaccharide mutants were significantly more sensitive to lysozyme and antimicrobial peptides, while the Hfq and anguibactin mutants were sensitive to lysozyme compared with the wild type. Vibrio anguillarum encodes several mechanisms to protect against antimicrobial components of skin mucus enabling an amazingly abundant growth on the skin enhancing its disease opportunities. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.