The Experts below are selected from a list of 14043 Experts worldwide ranked by ideXlab platform
Takuji Ishikawa - One of the best experts on this subject based on the ideXlab platform.
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what causes the spatial heterogeneity of bacterial Flora in the intestine of zebrafish larvae
Journal of Theoretical Biology, 2018Co-Authors: Yuji Shimogonya, Jinyou Yang, Takuji IshikawaAbstract:Abstract Microbial Flora in the intestine has been thoroughly investigated, as it plays an important role in the health of the host. Jemielita et al. (2014) showed experimentally that Aeromonas bacteria in the intestine of zebrafish larvae have a heterogeneous spatial distribution. Although bacterial aggregation is important biologically and clinically, there is no mathematical model describing the phenomenon and its mechanism remains largely unknown. In this study, we developed a computational model to describe the heterogeneous distribution of bacteria in the intestine of zebrafish larvae. The results showed that biological taxis could cause the bacterial aggregation. Intestinal peristalsis had the effect of reducing bacterial aggregation through mixing function. Using a scaling argument, we showed that the taxis velocity of bacteria must be larger than the sum of the diffusive velocity and background bulk flow velocity to induce bacterial aggregation. Our model and findings will be useful to further the scientific understanding of intestinal Microbial Flora.
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transport phenomena of Microbial Flora in the small intestine with peristalsis
Journal of Theoretical Biology, 2011Co-Authors: Takuji Ishikawa, T Sato, G Mohit, Yohsuke Imai, Takami YamaguchiAbstract:The gastrointestinal tract of humans is colonized by indigenous prokaryotic and eukaryotic Microbial cells that form a complex ecological system called Microbial Flora. Although the Microbial Flora has diverse functions, its homeostasis inside the gastrointestinal tract is still largely unknown. Therefore, creating a model for investigating Microbial Flora in the gastrointestinal tract is important. In this study, we developed a novel numerical model to explore the transport phenomena of Microbial Flora in the small intestine. By simultaneously solving the flow field generated by peristalsis, the concentrations of oxygen and nutrient, and the densities of moderate anaerobes and aerobes, the effects of fluid mechanics on the transport phenomena of Microbial Flora are discussed. The results clearly illustrated that fluid mechanics have considerable influence not only on the bacterial population, but also on the concentration distributions of oxygen and nutrient. Especially, the flow field enhances the radial variation of the concentration fields. We also show scaling arguments for bacterial growth and oxygen consumption, which capture the main features of the results. Additionally, we investigated the transport phenomena of Microbial Flora in a long tube with 40 constrictions. The results showed a high growth rate of aerobes in the upstream side and a high growth rate of anaerobes in the downstream side, which qualitatively agrees with experimental observations of human intestines. These new findings provide the fundamental basis for a better understanding of the transport phenomena of Microbial Flora in the intestine.
Maria Jesus Rodrigo - One of the best experts on this subject based on the ideXlab platform.
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effect of pef and heat pasteurization on the physical chemical characteristics of blended orange and carrot juice
Lwt - Food Science and Technology, 2006Co-Authors: A Rivas, D Rodrigo, Antonio Martinez, Gustavo V Barbosacanovas, Maria Jesus RodrigoAbstract:Abstract The effect of different Pulsed Electric Fields (PEF) intensities (25 kV/cm and 280 μs, P1; and 25 kV/cm and 330 μs, P2) and conventional HTST treatment (98 °C, 21 s, T) on quality characteristics (pH, °Brix, total acidity, turbidity, hydroxymethylfurfural (HMF), color, Microbial Flora, pectinmethylesterase (PME) activity, and sensory analysis) of blended orange and carrot juice were investigated. HMF, L* (luminosity) and C* (saturation or chrome) color parameters did not vary with any of the treatments. Total acidity and turbidity were slightly higher after HTST treatment. Sensory characteristics of the PEF-treated juice were more similar to the untreated juice than the HTST-pasteurized juice. Nevertheless, heat pasteurization (98 °C, 21 s) was more efficient in inactivating Microbial Flora and PME and preventing the growth of Microbial Flora and reactivation of PME at 2 and 12 °C for 10 weeks. However, the shelf-life of the PEF-treated juice was established as 4 weeks at 2 °C. This appears to be a reasonable shelf-life for this type of foodstuff.
Nosratola D Vaziri - One of the best experts on this subject based on the ideXlab platform.
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altered intestinal Microbial Flora and impaired epithelial barrier structure and function in ckd the nature mechanisms consequences and potential treatment
Nephrology Dialysis Transplantation, 2016Co-Authors: Nosratola D Vaziri, Yingyong Zhao, Madeleine V PahlAbstract:Chronic kidney disease (CKD) results in systemic inflammation and oxidative stress which play a central role in CKD progression and its adverse consequences. Although many of the causes and consequences of oxidative stress and inflammation in CKD have been extensively explored, little attention had been paid to the intestine and its Microbial Flora as a potential source of these problems. Our recent studies have revealed significant disruption of the colonic, ileal, jejunal and gastric epithelial tight junction in different models of CKD in rats. Moreover, the disruption of the epithelial barrier structure and function found in uremic animals was replicated in cultured human colonocytes exposed to uremic human plasma in vitro We have further found significant changes in the composition and function of colonic bacterial Flora in humans and animals with advanced CKD. Together, uremia-induced impairment of the intestinal epithelial barrier structure and function and changes in composition of the gut microbiome contribute to the systemic inflammation and uremic toxicity by accommodating the translocation of endotoxin, Microbial fragments and other noxious luminal products in the circulation. In addition, colonic bacteria are the main source of several well-known pro-inflammatory uremic toxins such as indoxyl sulfate, p-cresol sulfate, trimethylamine-N-oxide and many as-yet unidentified retained compounds in end-stage renal disease patients. This review is intended to provide an overview of the effects of CKD on the gut microbiome and intestinal epithelial barrier structure and their role in the pathogenesis of systemic inflammation and uremic toxicity. In addition, potential interventions aimed at mitigating these abnormalities are briefly discussed.
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chronic kidney disease alters intestinal Microbial Flora
Kidney International, 2013Co-Authors: Nosratola D Vaziri, Jakk Wong, Madeleine V Pahl, Yvette M Piceno, Jun Yuan, Todd Z Desantis, Tienhung Nguyen, Gary L AndersenAbstract:The population of microbes (microbiome) in the intestine is a symbiotic ecosystem conferring trophic and protective functions. Since the biochemical environment shapes the structure and function of the microbiome, we tested whether uremia and/or dietary and pharmacologic interventions in chronic kidney disease alters the microbiome. To identify different Microbial populations, Microbial DNA was isolated from the stools of 24 patients with end-stage renal disease (ESRD) and 12 healthy persons, and analyzed by phylogenetic microarray. There were marked differences in the abundance of 190 bacterial operational taxonomic units (OTUs) between the ESRD and control groups. OTUs from Brachybacterium, Catenibacterium, Enterobacteriaceae, Halomonadaceae, Moraxellaceae, Nesterenkonia, Polyangiaceae, Pseudomonadaceae, and Thiothrix families were markedly increased in patients with ESRD. To isolate the effect of uremia from inter-individual variations, comorbid conditions, and dietary and medicinal interventions, rats were studied 8 weeks post 5/6 nephrectomy or sham operation. This showed a significant difference in the abundance of 175 bacterial OTUs between the uremic and control animals, most notably as decreases in the Lactobacillaceae and Prevotellaceae families. Thus, uremia profoundly alters the composition of the gut microbiome. The biological impact of this phenomenon is unknown and awaits further investigation.
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ckd impairs barrier function and alters Microbial Flora of the intestine a major link to inflammation and uremic toxicity
Current Opinion in Nephrology and Hypertension, 2012Co-Authors: Nosratola D VaziriAbstract:Purpose of review Chronic kidney disease (CKD) is associated with oxidative stress and inflammation which contribute to progression of kidney disease and its numerous complications. Until recently, little attention had been paid to the role of the intestine and its Microbial Flora in the pathogenesis of CKD-associated inflammation. This article is intended to provide an over view of the impact of uremia on the structure and function of the gut and its Microbial Flora and their potential link to the associated systemic inflammation.
Jinyou Yang - One of the best experts on this subject based on the ideXlab platform.
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what causes the spatial heterogeneity of bacterial Flora in the intestine of zebrafish larvae
Journal of Theoretical Biology, 2018Co-Authors: Yuji Shimogonya, Jinyou Yang, Takuji IshikawaAbstract:Abstract Microbial Flora in the intestine has been thoroughly investigated, as it plays an important role in the health of the host. Jemielita et al. (2014) showed experimentally that Aeromonas bacteria in the intestine of zebrafish larvae have a heterogeneous spatial distribution. Although bacterial aggregation is important biologically and clinically, there is no mathematical model describing the phenomenon and its mechanism remains largely unknown. In this study, we developed a computational model to describe the heterogeneous distribution of bacteria in the intestine of zebrafish larvae. The results showed that biological taxis could cause the bacterial aggregation. Intestinal peristalsis had the effect of reducing bacterial aggregation through mixing function. Using a scaling argument, we showed that the taxis velocity of bacteria must be larger than the sum of the diffusive velocity and background bulk flow velocity to induce bacterial aggregation. Our model and findings will be useful to further the scientific understanding of intestinal Microbial Flora.
David Figdor - One of the best experts on this subject based on the ideXlab platform.
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contamination controls for analysis of root canal samples by molecular methods an overlooked and unsolved problem
Journal of Endodontics, 2016Co-Authors: David Figdor, Malin BrundinAbstract:Introduction: It has been almost 20 years since molecular methods were first described for the analysis of root canal Microbial Flora. Contamination control samples are essential to establish DNA d ...
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microbiologic analysis of teeth with failed endodontic treatment and the outcome of conservative re treatment
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 1998Co-Authors: Goran Sundqvist, David Figdor, Sten Persson, Ulf SjogrenAbstract:Objective. The purposes of this study were to determine what Microbial Flora were present in teeth after failed root canal therapy and to establish the outcome of conservative re-treatment. Study design. Fifty-four root-filled teeth with persisting periapical lesions were selected for re-treatment. After removal of the root filling, canals were sampled by means of advanced microbiologic techniques. The teeth were then re-treated and followed for up to 5 years. Results. The Microbial Flora was mainly single species of predominantly gram-positive organisms. The isolates most commonly recovered were bacteria of the species Enterococcus faecalis. The overall success rate of re-treatment was 74%. Conclusions. The Microbial Flora in canals after failed endodontic therapy differed markedly from the Flora in untreated teeth. Infection at the time of root filling and size of the periapical lesion were factors that had a negative influence on the prognosis. Three of four endodontic failures were successfully managed by re-treatment.