China
Africa
Explore chapters and articles related to this topic
Unexplained Fever In Infectious Diseases: Section 2: Commonly Encountered Aerobic, Facultative Anaerobic, And Strict Anaerobic Bacteria, Spirochetes, And Parasites
Published in Benedict Isaac, Serge Kernbaum, Michael Burke, Unexplained Fever, 2019
Bacteremia with Bacteroides fragilis may also be severe, the main clinical features being: abdominal abscesses, jaundice, thrombophlebitis and septic metastases (especially pulmonary). Table 4 lists the infections due to nonsporing endogenous anaerobes. Most of these infections are associated with fever.48,49
Bacteroides
Published in Dongyou Liu, Handbook of Foodborne Diseases, 2018
The genus Bacteroides covers a large number of strictly anaerobic or aerotolerant species that represent the most important components of the human resident intestinal microbiota. Bacteroides species living in the intestinal tract appear to be involved in processing complex molecules into simpler compounds that are used as nutrients by a human host as well as resident microbiota.
The large intestine
Published in Paul Ong, Rachel Skittrall, Gastrointestinal Nursing, 2017
The involvement of colonic bacteria in colorectal cancer has also been studied and increased numbers of bacteroides have been associated with increased risk of colon cancer (Heavey and Rowland, 2004). Bacteroides make up a major proportion of gut flora. Intestinal bacteria have also been shown to produce, from dietary components, substances which are carcinogenic (Moore and Moore, 1995; Heavey and Rowland, 2004).
Enterobacteriaceae and Bacteroidaceae provide resistance to travel-associated intestinal colonization by multi-drug resistant Escherichia coli
Published in Gut Microbes, 2022
Matthew Davies, Gianluca Galazzo, Jarne M. van Hattem, Maris S. Arcilla, Damian C. Melles, Menno D. de Jong, Constance Schultsz, Petra Wolffs, Alan McNally, Willem van Schaik, John Penders
Various Bacteroides species exhibit immunomodulatory effects that are beneficial to the host and can increase the colonization resistance to invading bacteria. A major mechanism of this is the inhibition of host inflammation via the secretion of sphingolipids,31 a signaling molecule or outer-member vesicles containing polysaccharide A,32 a molecule that induces the production of T cells to suppress inflammation.33 Low-grade intestinal inflammation perturbs the gut microbiome and can enhance the colonization of E. coli,34 so reducing this is vital to maintain colonization resistance to invading bacteria. Bacteroides species may have further immunomodulatory effects via the improvement of host macrophage’s phagocytic function35 or via an increased xylan degradation,36 which has links to an enhanced immune system and improved health.37,38 Moreover, Bacteroides species can produce a variety of short-chain fatty acids and organic acids, including acetic acid, propionic acid, isovaleric acid and succinic acid. Short-chain fatty acids have been shown to provide colonization resistance against antibiotic-resistant Enterobacteriaceae, among others, by triggering intracellular acidification.39 To reveal a potential protective role of metabolites, including sphingolipids, xylan breakdown products and short-chain fatty acids, produced by Bacteroides species or other members of the microbiome, future studies on the fecal metabolome are warranted.
A decrease in functional microbiomes represented as Faecalibacterium affects immune homeostasis in long-term stable liver transplant patients
Published in Gut Microbes, 2022
Soon Kyu Lee, JooYeon Jhun, Seung Yoon Lee, Sukjung Choi, Sun Shim Choi, Myeong Soo Park, Seon-Young Lee, Keun-Hyung Cho, A Ram Lee, Joseph Ahn, Ho Joong Choi, Young Kyoung You, Pil Soo Sung, Jeong Won Jang, Si Hyun Bae, Seung Kew Yoon, Mi-La Cho, Jong Young Choi
Considering the significant difference in the abundance of bacteria and immunological imbalance in the long-term post-LT patients, we next tried to identify the functional microbiomes affecting immune homeostasis in these patients. As shown in Figure 2d and Figure 3a, the Faecalibacterium genus and its species, Faecalibacterium prausnitzii , was significantly decreased (P = .025 and P = .0032, respectively). The Bacteroides genus was increased (P = .0008) in the long-term post-LT patients than in healthy controls, which were the most decreased and increased abundance of bacteria in the long-term post-LT patients, respectively. The Bifidobacterium genus and its species, Bifidobacterium longum , and Bifidobacterium bifidum , were marginally decreased in the long-term post-LT patients (Figure 3a and Supplementary Figure 1A). Moreover, the Akkermansia genus and its species, Akkermansia muciniphila , were considerably decreased and nearly undetectable in the long-term post-LT patients (Figure 3a and Supplementary Figure 1A).
Gut Bacteroides species in health and disease
Published in Gut Microbes, 2021
Metabolites secreted by different Bacteroides spp. assist in maintaining stability of the immune system. These species are primary producers of short-chain fatty acids in the human gut, mostly in the form of acetate and propionate. These are important for the maintenance of intestinal homeostasis.171 Both acetate and propionate are potent anti-inflammatory mediators as they inhibit the release of pro-inflammatory cytokines from neutrophils and macrophages.172 Cruz-Bravo et al. described an anti-cancerous role of propionate which induced apoptosis in human colon carcinoma cells.173 Also, butyrate increases expression of tight-junction proteins in the gut to reduce potential gut hyperpermeability. This, in turn, decreases inflammation and endotoxemia that are associated with leaky gut.174 In the human gut, Bacteroides spp. are the principal synthesizers of Vitamin K, which is mainly produced by members of the human gut bacteriome.175 It may prevent or treat osteoporosis by increasing the bone mineral density.176