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World Journal of Gastroenterology Aug 2022The gut microbiota is a complex community of microorganisms that inhabit the digestive tracts of humans, living in symbiosis with the host. Dysbiosis, characterized by... (Review)
Review
The gut microbiota is a complex community of microorganisms that inhabit the digestive tracts of humans, living in symbiosis with the host. Dysbiosis, characterized by an imbalance between the beneficial and opportunistic gut microbiota, is associated with several gastrointestinal disorders, such as irritable bowel syndrome (IBS); inflammatory bowel disease (IBD), represented by ulcerative colitis and Crohn's disease; and colorectal cancer (CRC). Dysbiosis can disrupt the mucosal barrier, resulting in perpetuation of inflammation and carcinogenesis. The increase in some specific groups of harmful bacteria, such as () and enterotoxigenic (ETBF), has been associated with chronic tissue inflammation and the release of pro-inflammatory and carcinogenic mediators, increasing the chance of developing CRC, following the inflammation-dysplasia-cancer sequence in IBD patients. Therefore, the aim of the present review was to analyze the correlation between changes in the gut microbiota and the development and maintenance of IBD, CRC, and IBD-associated CRC. Patients with IBD and CRC have shown reduced bacterial diversity and abundance compared to healthy individuals, with enrichment of and . Specific bacteria are also associated with the onset and progression of CRC, such as , , , , and ETBF. Future research can evaluate the advantages of modulating the gut microbiota as preventive measures in CRC high-risk patients, directly affecting the prognosis of the disease and the quality of life of patients.
Topics: Bacteria; Bacteroides fragilis; Colorectal Neoplasms; Dysbiosis; Escherichia coli; Gastrointestinal Microbiome; Humans; Inflammation; Inflammatory Bowel Diseases; Quality of Life; Sand
PubMed: 36157114
DOI: 10.3748/wjg.v28.i30.4053 -
European Heart Journal Oct 2019The EURO-ENDO registry aimed to study the management and outcomes of patients with infective endocarditis (IE). (Observational Study)
Observational Study
Clinical presentation, aetiology and outcome of infective endocarditis. Results of the ESC-EORP EURO-ENDO (European infective endocarditis) registry: a prospective cohort study.
AIMS
The EURO-ENDO registry aimed to study the management and outcomes of patients with infective endocarditis (IE).
METHODS AND RESULTS
Prospective cohort of 3116 adult patients (2470 from Europe, 646 from non-ESC countries), admitted to 156 hospitals in 40 countries between January 2016 and March 2018 with a diagnosis of IE based on ESC 2015 diagnostic criteria. Clinical, biological, microbiological, and imaging [echocardiography, computed tomography (CT) scan, 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT)] data were collected. Infective endocarditis was native (NVE) in 1764 (56.6%) patients, prosthetic (PVIE) in 939 (30.1%), and device-related (CDRIE) in 308 (9.9%). Infective endocarditis was community-acquired in 2046 (65.66%) patients. Microorganisms involved were staphylococci in 1085 (44.1%) patients, oral streptococci in 304 (12.3%), enterococci in 390 (15.8%), and Streptococcus gallolyticus in 162 (6.6%). 18F-fluorodeoxyglucose positron emission tomography/computed tomography was performed in 518 (16.6%) patients and presented with cardiac uptake (major criterion) in 222 (42.9%) patients, with a better sensitivity in PVIE (66.8%) than in NVE (28.0%) and CDRIE (16.3%). Embolic events occurred in 20.6% of patients, and were significantly associated with tricuspid or pulmonary IE, presence of a vegetation and Staphylococcus aureus IE. According to ESC guidelines, cardiac surgery was indicated in 2160 (69.3%) patients, but finally performed in only 1596 (73.9%) of them. In-hospital death occurred in 532 (17.1%) patients and was more frequent in PVIE. Independent predictors of mortality were Charlson index, creatinine > 2 mg/dL, congestive heart failure, vegetation length > 10 mm, cerebral complications, abscess, and failure to undertake surgery when indicated.
CONCLUSION
Infective endocarditis is still a life-threatening disease with frequent lethal outcome despite profound changes in its clinical, microbiological, imaging, and therapeutic profiles.
Topics: Adult; Africa, Northern; Aged; Aged, 80 and over; Asia; Community-Acquired Infections; Echocardiography; Embolism; Endocarditis, Bacterial; Enterococcus; Europe; Female; Fluorodeoxyglucose F18; Heart Valve Prosthesis; Hospital Mortality; Humans; Male; Middle Aged; Positron Emission Tomography Computed Tomography; Prospective Studies; Prosthesis-Related Infections; Radiopharmaceuticals; Registries; South America; Staphylococcal Infections; Streptococcal Infections; Treatment Outcome
PubMed: 31504413
DOI: 10.1093/eurheartj/ehz620 -
Chinese Medical Journal Dec 2021Colorectal cancer (CRC) is one of the most prevalent, most lethal cancers in the world. Increasing evidence suggests that the intestinal microbiota is closely related to... (Review)
Review
Colorectal cancer (CRC) is one of the most prevalent, most lethal cancers in the world. Increasing evidence suggests that the intestinal microbiota is closely related to the pathogenesis and prognosis of CRC. The normal microbiota plays an essential role in maintaining gut barrier function and the immune microenvironment. Recent studies have identified carcinogenic bacteria such as enterotoxigenic Bacteroides fragilis (ETBF) and Streptococcus gallolyticus (S. gallolyticus), as well as protective bacterial such as Akkermansia muciniphila (A. muciniphila), as potential targets of CRC treatment. Gut microbiota modulation aims to restore gut dysbiosis, regulate the intestinal immune system and prevent from pathogen invasion, all of which are beneficial for CRC prevention and prognosis. The utility of probiotics, prebiotics, postbiotics, fecal microbiota transplantation and dietary inventions to treat CRC makes them novel microbe-based management tools. In this review, we describe the mechanisms involved in bacteria-derived colorectal carcinogenesis and summarized novel bacteria-related therapies for CRC. In summary, we hope to facilitate clinical applications of intestinal bacteria for preventing and treating CRC.
Topics: Colorectal Neoplasms; Dysbiosis; Fecal Microbiota Transplantation; Gastrointestinal Microbiome; Humans; Prebiotics; Tumor Microenvironment
PubMed: 34855639
DOI: 10.1097/CM9.0000000000001887 -
Frontiers in Microbiology 2018subsp. (formerly known as type I) is the main causative agent of septicemia and infective endocarditis (IE) in elderly and immunocompromised persons. It belongs to... (Review)
Review
subsp. (formerly known as type I) is the main causative agent of septicemia and infective endocarditis (IE) in elderly and immunocompromised persons. It belongs to the few opportunistic bacteria, which have been strongly associated to colorectal cancer (CRC). A literature survey covering a period of 40 years (1970-2010) revealed that 65% of patients diagnosed with an invasive infection had a concomitant colorectal neoplasia. is associated mainly with early adenomas and may thus constitute an early marker for CRC screening. has been described as a normal inhabitant of the rumen of herbivores and in the digestive tract of birds. It is more rarely detected in human intestinal tract (2.5-15%). Recent molecular analyses indicate possible zoonotic transmission of . Thanks to the development of a genetic toolbox and to comparative genomics, a number of factors that are important for pathogenicity have been identified. This review will highlight the role of pili in host colonization and how their phase-variable expression contributes to mitigate the host immune responses and finally their use as serological diagnostic tool. We will then present experimental data addressing the core question whether is a cause or consequence of CRC. We will discuss a few recent studies examining the etiological versus non-etiological participation of in colorectal cancer with the underlying mechanisms.
PubMed: 29666615
DOI: 10.3389/fmicb.2018.00614 -
Virulence Jan 2018Streptococcus gallolyticus subsp. gallolyticus, formerly classified as S. bovis biotype I, is an increasing cause of bacteremia and infective endocarditis in the...
Streptococcus gallolyticus subsp. gallolyticus, formerly classified as S. bovis biotype I, is an increasing cause of bacteremia and infective endocarditis in the elderly. The physiopathology of infective endocarditis is poorly understood and involves immune and coagulation systems. In this study, we found that S. gallolyticus subsp. gallolyticus activates the human contact system, which in turn has two consequences: cleavage of high-molecular-weight kininogen (HK) resulting in release of the potent pro-inflammatory peptide bradykinin, and initiation of the intrinsic pathway of coagulation. S. gallolyticus subsp. gallolyticus was found to bind and activate factors of the human contact system at its surface, leading to a significant prolongation of the intrinsic coagulation time and to the release of bradykinin. High-affinity binding of factor XII to the bacterial Pil1 collagen binding protein was demonstrated with a K of 13 nM. Of note, Pil1 expression was exclusively found in S. gallolyticus subsp. gallolyticus, further supporting an essential contribution of this pilus in virulence.
Topics: Bacterial Proteins; Blood Coagulation; Blood Coagulation Factors; Factor XII; Fimbriae, Bacterial; Kininogen, High-Molecular-Weight; Prekallikrein; Protein Binding; Streptococcal Infections; Streptococcus gallolyticus subspecies gallolyticus; Virulence; Virulence Factors
PubMed: 29072555
DOI: 10.1080/21505594.2017.1393600 -
Journal of Bacteriology Jul 2018subsp. , a member of the group D streptococci, is normally found in the bovine rumen and human gut. It is an opportunistic pathogen that was recently determined to be a...
subsp. , a member of the group D streptococci, is normally found in the bovine rumen and human gut. It is an opportunistic pathogen that was recently determined to be a bacterial driver of colorectal cancer, in addition to causing other diseases, such as infective endocarditis, bacteremia, neonatal meningitis, and septicemia. As an emerging pathogen, not much is known about this bacterium, its virulence mechanisms, or its virulence regulatory pathways. Previous studies suggest that subsp. uses a ComRS pathway, one of many quorum-sensing circuitries, for competence. However, thus far, the ubiquitous ComABCDE pathway has not been studied, nor has its regulatory role in subsp. We therefore sought to study the subsp. ComABCDE quorum-sensing pathway and have identified its peptide pheromone, which is termed the competence-stimulating peptide (CSP). We further determined that this peptide regulates the production of bacteriocin-like inhibitory substances (BLISs), a phenotype that has been linked with the ComABCDE pathway in both and Our data show that subsp. TX20005 produces a 21-mer CSP signal, which differs from CSP signals of other species in that its active form begins three residues after the double-glycine leader signal of the ComC precursor peptide. Additionally, our data suggest that this peptide might not be related to competence induction, as opposed to CSP signaling peptides in other species. This study provides the first evidence that subsp. utilizes quorum sensing to eliminate competitors, presenting a potential pathway to target this emerging human pathogen. subsp. is an emerging human pathogen known as a causative agent of infective endocarditis, and recently, of colorectal cancer. In this work, we revealed a functional quorum-sensing circuitry in subsp. , including the identification of the central signaling peptide pheromone, competence-stimulating peptide (CSP), and the regulatory role of this circuitry in the production of bacteriocin-like inhibitory substances (BLISs). This work uncovered a mechanism by which this bacterium outcompetes other bacterial species and thus provides a potential tool to study this opportunistic pathogen.
Topics: Amino Acid Sequence; Bacterial Proteins; Bacteriocins; Biofilms; Gene Expression Regulation, Bacterial; RNA Polymerase II; Sequence Alignment; Streptococcus gallolyticus subspecies gallolyticus; Transformation, Genetic
PubMed: 29440256
DOI: 10.1128/JB.00709-17 -
Journal of Experimental & Clinical... Jan 2011Streptococcus bovis (S. bovis) bacteria are associated with colorectal cancer and adenoma. S. bovis is currently named S. gallolyticus. 25 to 80% of patients with S.... (Review)
Review
Streptococcus bovis (S. bovis) bacteria are associated with colorectal cancer and adenoma. S. bovis is currently named S. gallolyticus. 25 to 80% of patients with S. bovis/gallolyticus bacteremia have concomitant colorectal tumors. Colonic neoplasia may arise years after the presentation of bacteremia or infectious endocarditis of S. bovis/gallolyticus. The presence of S. bovis/gallolyticus bacteremia and/or endocarditis is also related to the presence of villous or tubular-villous adenomas in the large intestine. In addition, serological relationship of S. gallolyticus with colorectal tumors and direct colonization of S. gallolyticus in tissues of colorectal tumors were found. However, this association is still under controversy and has long been underestimated. Moreover, the etiological versus non-etiological nature of this associationis not settled yet. Therefore, by covering the most of up to date studies, this review attempts to clarify the nature and the core of S. bovis/gallolyicus association with colorectal tumors and analyze the possible underlying mechanisms.
Topics: Adenoma; Animals; Bacteremia; Colorectal Neoplasms; Endocarditis; Gastrointestinal Tract; Humans; Inflammation; Intestinal Mucosa; Precancerous Conditions; Streptococcal Infections; Streptococcus bovis
PubMed: 21247505
DOI: 10.1186/1756-9966-30-11 -
The Journal of Veterinary Medical... Jan 2022A 179-day-old calf, which was weak and stunted, showed neurological signs and was euthanized. Postmortem examination revealed extensive and severe cloudy area in the...
A 179-day-old calf, which was weak and stunted, showed neurological signs and was euthanized. Postmortem examination revealed extensive and severe cloudy area in the meninges, and pleural pneumonia. Gram-positive cocci were isolated from systemic organs. Biochemical and 16S rRNA gene sequence analyses identified the isolate as Streptococcus gallolyticus, and its subspecies was suggested to be gallolyticus (SGG). The isolate was classified as a novel sequence type (ST115) by the multilocus sequence typing scheme for SGG and showed susceptibility to penicillin, ampicillin, amoxicillin, florfenicol, sulfamethoxazole-trimethoprim, and chloramphenicol. Histopathologically, suppurative meningoencephalitis and perineuritis were detected. As SGG has been isolated solely from a cow with mastitis in Japan, this is the first SGG infection in a calf with suppurative meningoencephalitis and perineuritis in this country.
Topics: Animals; Cattle; Cattle Diseases; Female; Meningoencephalitis; Multilocus Sequence Typing; RNA, Ribosomal, 16S; Streptococcal Infections; Streptococcus gallolyticus
PubMed: 34819412
DOI: 10.1292/jvms.21-0518 -
Journal of Clinical Medicine Apr 2022The role of colorectal neoplasms (CRN) as a common potential source of recurrent subsp. (SGG) and (EF) endocarditis remains unstudied. We aimed to investigate what...
OBJECTIVES
The role of colorectal neoplasms (CRN) as a common potential source of recurrent subsp. (SGG) and (EF) endocarditis remains unstudied. We aimed to investigate what proportion of episodes of recurrent endocarditis are caused by a succession of SGG and EF, or vice versa, and to assess the role of a colonic source in such recurrent episodes.
METHODS
we conducted a retrospective analysis of two prospective endocarditis cohorts (1979-2019) from two Spanish hospitals, providing descriptive analyses of the major features of the endocarditis episodes, colonoscopy findings, and histologic results.
RESULTS
among 1552 IE episodes, 204 (13.1%) were caused by EF and 197 (12.7%) by SGG, respectively. There were 155 episodes (10%) of recurrent IE, 20 of which (12.9%) were due to a succession of SGG/EF IE in 10 patients (the first episode caused by SGG in eight cases, and by EF in two cases). The median follow-up was 86 (interquartile range 34-156) months. In 8/10 initial episodes, the causative microorganism was SGG, and all patients were diagnosed with CRN either during the initial episode or during follow-up. During the second episode of IE or follow-up, colonoscopies revealed CRN in six patients.
CONCLUSIONS
There seems to be an association between SGG and EF in recurrent endocarditis that warrants further investigation. Our findings reinforce the need for systematically performing colonoscopy in the event of endocarditis caused by both microorganisms.
PubMed: 35456274
DOI: 10.3390/jcm11082181 -
Emerging Infectious Diseases Jan 2022To evaluate trends in bacterial causes of valvular endocarditis in swine, we retrospectively analyzed 321 cases diagnosed at Iowa State University Veterinary Diagnostic...
To evaluate trends in bacterial causes of valvular endocarditis in swine, we retrospectively analyzed 321 cases diagnosed at Iowa State University Veterinary Diagnostic Laboratory (Ames, IA, USA) during May 2015--April 2020. Streptococcus gallolyticus was the causative agent for 7.59% of cases. This emerging infection in swine could aid study of endocarditis in humans.
Topics: Animals; Endocarditis; Endocarditis, Bacterial; Retrospective Studies; Streptococcal Infections; Streptococcus gallolyticus; Swine; United States
PubMed: 34932445
DOI: 10.3201/eid2801.210998