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Scientific Reports Aug 2021Understanding changes in oral flora during pregnancy, its association to maternal health, and its implications to birth outcomes is essential. We searched PubMed,... (Meta-Analysis)
Meta-Analysis
Understanding changes in oral flora during pregnancy, its association to maternal health, and its implications to birth outcomes is essential. We searched PubMed, Embase, Web of Science, and Cochrane Library in May 2020 (updated search in April and June 2021), and conducted a systematic review and meta-analyses to assess the followings: (1) oral microflora changes throughout pregnancy, (2) association between oral microorganisms during pregnancy and maternal oral/systemic conditions, and (3) implications of oral microorganisms during pregnancy on birth outcomes. From 3983 records, 78 studies were included for qualitative assessment, and 13 studies were included in meta-analysis. The oral microflora remains relatively stable during pregnancy; however, pregnancy was associated with distinct composition/abundance of oral microorganisms when compared to postpartum/non-pregnant status. Oral microflora during pregnancy appears to be influenced by oral and systemic conditions (e.g. gestational diabetes mellitus, pre-eclampsia, etc.). Prenatal dental care reduced the carriage of oral pathogens (e.g. Streptococcus mutans). The Porphyromonas gingivalis in subgingival plaque was more abundant in women with preterm birth. Given the results from meta-analyses were inconclusive since limited studies reported outcomes on the same measuring scale, more future studies are needed to elucidate the association between pregnancy oral microbiota and maternal oral/systemic health and birth outcomes.
Topics: Female; Humans; Microbiota; Mouth; Periodontal Diseases; Pregnancy; Pregnancy Outcome; Premature Birth; Publication Bias; Risk
PubMed: 34413437
DOI: 10.1038/s41598-021-96495-1 -
Applied and Environmental Microbiology Jul 2019spp. are among the most important foodborne pathogens and the third leading cause of human death among diarrheal diseases worldwide. Animals are the primary source of... (Meta-Analysis)
Meta-Analysis
spp. are among the most important foodborne pathogens and the third leading cause of human death among diarrheal diseases worldwide. Animals are the primary source of this pathogen, and animal-based foods are the main transmission route to humans. Thus, understanding the global epidemiology of serovars is key to controlling and monitoring this bacterium. In this context, this study aimed to evaluate the prevalence and diversity of serovars in animal-based foods (beef, pork, poultry, and seafood) throughout the five continents (Africa, the Americas [North and Latin America], Asia, Europe, and Oceania). The meta-analysis consisted of a chemometric assessment (hierarchical cluster analysis and principal component analysis) to identify the main epidemiological findings, including the prevalence and diversity of the serovars in each matrix. Regarding the serovar distribution, Typhimurium presented a cosmopolitan distribution, reported in all four assessed matrices and continents; poultry continues to play a central role in the dissemination of the Enteritidis serovar to humans, and Anatum and Weltevreden were the most frequently found in beef and seafood, respectively. Additionally, we recommended careful monitoring of certain serovars, such as Derby, Agona, Infantis, and Kentucky. Finally, given the scientific data regarding the most frequently reported serovars and which matrices constitute the main vehicles for the transmission of this pathogen, control programs may be improved, and specific interventions may be implemented in an attempt to reduce the risk of this pathogen reaching humans. Salmonellosis is caused by spp. and is the third leading cause of death among food-transmitted diseases. This pathogen is commonly disseminated in domestic and wild animals, and the infection's symptoms are characterized by acute fever, nausea, abdominal pain, and diarrhea. The animals are the primary source of salmonellae, and animal-based foods are the main transmission route to humans. Therefore, data collected from these sources could contribute to future global interventions for effective control and surveillance of along the food chain. In light of this, the importance of our research is in identifying the prevalence of serovars in four animal-based food matrices (pork, poultry, beef, and seafood) and to evaluate the importance that each matrix has as the primary source of this pathogen to humans.
Topics: Animals; Food Microbiology; Prevalence; Salmonella Infections, Animal; Salmonella enterica; Serogroup
PubMed: 31053586
DOI: 10.1128/AEM.00591-19 -
International Journal of Environmental... Mar 2023Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disease mediated by autoimmune reactions against myelin proteins and gangliosides in the grey and... (Review)
Review
INTRODUCTION
Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disease mediated by autoimmune reactions against myelin proteins and gangliosides in the grey and white matter of the brain and spinal cord. It is considered one of the most common neurological diseases of non-traumatic origin in young people, especially in women. Recent studies point to a possible association between MS and gut microbiota. Intestinal dysbiosis has been observed, as well as an alteration of short-chain fatty acid-producing bacteria, although clinical data remain scarce and inconclusive.
OBJECTIVE
To conduct a systematic review on the relationship between gut microbiota and multiple sclerosis.
METHOD
The systematic review was conducted in the first quarter of 2022. The articles included were selected and compiled from different electronic databases: PubMed, Scopus, ScienceDirect, Proquest, Cochrane, and CINAHL. The keywords used in the search were: "multiple sclerosis", "gut microbiota", and "microbiome".
RESULTS
12 articles were selected for the systematic review. Among the studies that analysed alpha and beta diversity, only three found significant differences with respect to the control. In terms of taxonomy, the data are contradictory, but confirm an alteration of the microbiota marked by a decrease in Firmicutes, Lachnospiraceae, , , , , , , , and and an increase in Bacteroidetes, , , and . As for short-chain fatty acids, in general, a decrease in short-chain fatty acids, in particular butyrate, was observed.
CONCLUSIONS
Gut microbiota dysbiosis was found in multiple sclerosis patients compared to controls. Most of the altered bacteria are short-chain fatty acid (SCFA)-producing, which could explain the chronic inflammation that characterises this disease. Therefore, future studies should consider the characterisation and manipulation of the multiple sclerosis-associated microbiome as a focus of both diagnostic and therapeutic strategies.
Topics: Humans; Female; Adolescent; Dysbiosis; Neurodegenerative Diseases; Sclerosis; Microbiota; Fatty Acids, Volatile; Multiple Sclerosis; Bacteria
PubMed: 36901634
DOI: 10.3390/ijerph20054624 -
Journal of Clinical Periodontology Mar 2017The oral microbiome is diverse and exists as multispecies microbial communities on oral surfaces in structurally and functionally organized biofilms. (Review)
Review
BACKGROUND
The oral microbiome is diverse and exists as multispecies microbial communities on oral surfaces in structurally and functionally organized biofilms.
AIM
To describe the network of microbial interactions (both synergistic and antagonistic) occurring within these biofilms and assess their role in oral health and dental disease.
METHODS
PubMed database was searched for studies on microbial ecological interactions in dental biofilms. The search results did not lend themselves to systematic review and have been summarized in a narrative review instead.
RESULTS
Five hundred and forty-seven original research articles and 212 reviews were identified. The majority (86%) of research articles addressed bacterial-bacterial interactions, while inter-kingdom microbial interactions were the least studied. The interactions included physical and nutritional synergistic associations, antagonism, cell-to-cell communication and gene transfer.
CONCLUSIONS
Oral microbial communities display emergent properties that cannot be inferred from studies of single species. Individual organisms grow in environments they would not tolerate in pure culture. The networks of multiple synergistic and antagonistic interactions generate microbial inter-dependencies and give biofilms a resilience to minor environmental perturbations, and this contributes to oral health. If key environmental pressures exceed thresholds associated with health, then the competitiveness among oral microorganisms is altered and dysbiosis can occur, increasing the risk of dental disease.
Topics: Biofilms; Humans; Microbial Interactions; Microbiota; Mouth Diseases; Oral Health; Tooth
PubMed: 28266111
DOI: 10.1111/jcpe.12679 -
Critical Reviews in Food Science and... 2023Kombucha is a fermented nonalcoholic tea-based beverage produced through a symbiotic culture of bacteria and yeasts. studies have demonstrated antimicrobial,...
Kombucha is a fermented nonalcoholic tea-based beverage produced through a symbiotic culture of bacteria and yeasts. studies have demonstrated antimicrobial, antioxidant, antiproliferative, and anti-carcinogenic properties of kombucha. However, no systematic reviews have evaluated the effects of kombucha . Thus, we aimed to evaluate the evidence that exists so far about kombucha consumption on comorbidities associated with obesity as well as on the gut microbiota. The search was conducted in accordance with PRISMA and the protocol was registered in PROSPERO (registration number: CRD42020158917). The MEDLINE/PubMed, Web of Science, LILACS, SciELO, Scopus, and Science Direct databases were used in the search considering the following terms: "kombucha" OR "kombucha tea" OR "kombucha teas" OR "tea, kombucha" OR "teas, kombucha" NOT "review." Fifteen studies were included in this review. The results suggest that kombucha consumption attenuates oxidative stress and inflammation, improves the liver detoxification process, and reduces intestinal dysbiosis. There is evidence that kombucha consumption is beneficial for the control and treatment of obesity and associated comorbidities, as well as for the modulation of the gut microbiota .
Topics: Gastrointestinal Microbiome; Kombucha Tea; Beverages; Yeasts; Obesity; Fermentation; Tea
PubMed: 34698580
DOI: 10.1080/10408398.2021.1995321 -
Influenza and Other Respiratory Viruses Sep 2016Coinfecting bacterial pathogens are a major cause of morbidity and mortality in influenza. However, there remains a paucity of literature on the magnitude of coinfection... (Meta-Analysis)
Meta-Analysis Review
AIM
Coinfecting bacterial pathogens are a major cause of morbidity and mortality in influenza. However, there remains a paucity of literature on the magnitude of coinfection in influenza patients.
METHOD
A systematic search of MeSH, Cochrane Library, Web of Science, SCOPUS, EMBASE, and PubMed was performed. Studies of humans in which all individuals had laboratory confirmed influenza, and all individuals were tested for an array of common bacterial species, met inclusion criteria.
RESULTS
Twenty-seven studies including 3215 participants met all inclusion criteria. Common etiologies were defined from a subset of eight articles. There was high heterogeneity in the results (I(2) = 95%), with reported coinfection rates ranging from 2% to 65%. Although only a subset of papers were responsible for observed heterogeneity, subanalyses and meta-regression analysis found no study characteristic that was significantly associated with coinfection. The most common coinfecting species were Streptococcus pneumoniae and Staphylococcus aureus, which accounted for 35% (95% CI, 14%-56%) and 28% (95% CI, 16%-40%) of infections, respectively; a wide range of other pathogens caused the remaining infections. An assessment of bias suggested that lack of small-study publications may have biased the results.
CONCLUSIONS
The frequency of coinfection in the published studies included in this review suggests that although providers should consider possible bacterial coinfection in all patients hospitalized with influenza, they should not assume all patients are coinfected and be sure to properly treat underlying viral processes. Further, high heterogeneity suggests additional large-scale studies are needed to better understand the etiology of influenza bacterial coinfection.
Topics: Adolescent; Adult; Child; Child, Preschool; Coinfection; Drug Resistance, Bacterial; Female; Hospitalization; Humans; Infant; Infant, Newborn; Influenza, Human; Male; Methicillin-Resistant Staphylococcus aureus; Middle Aged; Pneumococcal Infections; Staphylococcal Infections; Streptococcus pneumoniae; Young Adult
PubMed: 27232677
DOI: 10.1111/irv.12398 -
Nutrients Dec 2022The microbiota, as a complex of microorganisms in a particular ecosystem, is part of the wider term-microbiome, which is defined as the set of all genetic content in the... (Review)
Review
The microbiota, as a complex of microorganisms in a particular ecosystem, is part of the wider term-microbiome, which is defined as the set of all genetic content in the microbial community. Imbalanced gut microbiota has a great impact on the homeostasis of the organism. Dysbiosis, as a disturbance in bacterial balance, might trigger or exacerbate the course of different pathologies. Small intestinal bacterial overgrowth (SIBO) is a disorder characterized by differences in quantity, quality, and location of the small intestine microbiota. SIBO underlies symptoms associated with functional gastrointestinal disorders (FGD) as well as may alter the presentation of chronic diseases such as heart failure, diabetes, etc. In recent years there has been growing interest in the influence of SIBO and its impact on the whole human body as well as individual systems. Therefore, we aimed to investigate the co-existence of SIBO with different medical conditions. The PubMed database was searched up to July 2022 and we found 580 original studies; inclusion and exclusion criteria let us identify 112 eligible articles, which are quoted in this paper. The present SIBO diagnostic methods could be divided into two groups-invasive, the gold standard-small intestine aspirate culture, and non-invasive, breath tests (BT). Over the years scientists have explored SIBO and its associations with other diseases. Its role has been confirmed not only in gastroenterology but also in cardiology, endocrinology, neurology, rheumatology, and nephrology. Antibiotic therapy could reduce SIBO occurrence resulting not only in the relief of FGD symptoms but also manifestations of comorbid diseases. Although more research is needed, the link between SIBO and other diseases is an important pathway for scientists to follow.
Topics: Humans; Intestine, Small; Anti-Bacterial Agents; Blind Loop Syndrome; Irritable Bowel Syndrome; Microbiota; Breath Tests
PubMed: 36615748
DOI: 10.3390/nu15010090 -
American Journal of Respiratory Cell... Mar 2023Microorganisms colonize the human body. The lungs and respiratory tract, previously believed to be sterile, harbor diverse microbial communities and the genomes of...
Microorganisms colonize the human body. The lungs and respiratory tract, previously believed to be sterile, harbor diverse microbial communities and the genomes of bacteria (bacteriome), viruses (virome), and fungi (mycobiome). Recent advances in amplicon and shotgun metagenomic sequencing technologies and data-analyzing methods have greatly aided the identification and characterization of microbial populations from airways. The respiratory microbiome has been shown to play roles in human health and disease and is an area of rapidly emerging interest in pulmonary medicine. In this review, we provide updated information in the field by focusing on four lung conditions, including asthma, chronic obstructive pulmonary disease, cystic fibrosis, and idiopathic pulmonary fibrosis. We evaluate gut, oral, and upper airway microbiomes and how they contribute to lower airway flora. The discussion is followed by a systematic review of the lower airway microbiome in health and disease. We conclude with promising research avenues and implications for evolving therapeutics.
Topics: Humans; Lung; Asthma; Pulmonary Disease, Chronic Obstructive; Microbiota; Cystic Fibrosis
PubMed: 36476129
DOI: 10.1165/rcmb.2022-0208TR -
Journal of Alzheimer's Disease : JAD 2023Pre-clinical evidence implicates oral bacteria in the pathogenesis of Alzheimer's disease (AD), while clinical studies show diverse results. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Pre-clinical evidence implicates oral bacteria in the pathogenesis of Alzheimer's disease (AD), while clinical studies show diverse results.
OBJECTIVE
To comprehensively assess the association between oral bacteria and AD with clinical evidence.
METHODS
Studies investigating the association between oral bacteria and AD were identified through a systematic search of six databases PubMed, Embase, Cochrane Central Library, Scopus, ScienceDirect, and Web of Science. Methodological quality ratings of the included studies were performed. A best evidence synthesis was employed to integrate the results. When applicable, a meta-analysis was conducted using a random-effect model.
RESULTS
Of the 16 studies included, ten investigated periodontal pathobionts and six were microbiome-wide association studies. Samples from the brain, serum, and oral cavity were tested. We found over a ten-fold and six-fold increased risk of AD when there were oral bacteria (OR = 10.68 95% CI: 4.48-25.43; p < 0.00001, I2 = 0%) and Porphyromonas gingivalis (OR = 6.84 95% CI: 2.70-17.31; p < 0.0001, I2 = 0%) respectively in the brain. While AD patients exhibited lower alpha diversity of oral microbiota than healthy controls, the findings of bacterial communities were inconsistent among studies. The best evidence synthesis suggested a moderate level of evidence for an overall association between oral bacteria and AD and for oral bacteria being a risk factor for AD.
CONCLUSION
Current evidence moderately supports the association between oral bacteria and AD, while the association was strong when oral bacteria were detectable in the brain. Further evidence is needed to clarify the interrelationship between both individual species and bacterial communities and the development of AD.
Topics: Humans; Alzheimer Disease; Cognitive Dysfunction; Risk Factors; Microbiota; Porphyromonas gingivalis
PubMed: 36404545
DOI: 10.3233/JAD-220627 -
International Journal of Molecular... Nov 2022There is a growing body of evidence highlighting there are significant changes in the gut microbiota composition and relative abundance in various neurological... (Review)
Review
There is a growing body of evidence highlighting there are significant changes in the gut microbiota composition and relative abundance in various neurological disorders. We performed a systematic review of the different microbiota altered in a wide range of neurological disorders (Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis, and stroke). Fifty-two studies were included representing 5496 patients. At the genus level, the most frequently involved microbiota are Akkermansia, Faecalibacterium, and Prevotella. The overlap between the pathologies was strongest for MS and PD, sharing eight genera (Akkermansia, Butyricicoccus, Bifidobacterium, Coprococcus, Dorea, Faecalibacterium, Parabacteroides, and Prevotella) and PD and stroke, sharing six genera (Enterococcus, Faecalibacterium, Lactobacillus, Parabacteroides, Prevotella, and Roseburia). The identification signatures overlapping for AD, PD, and MS raise the question of whether these reflect a common etiology or rather common consequence of these diseases. The interpretation is hampered by the low number and low power for AD, ALS, and stroke with ample opportunity for false positive and false negative findings.
Topics: Humans; Gastrointestinal Microbiome; Nervous System Diseases; Parkinson Disease; Microbiota; Akkermansia; Multiple Sclerosis; Prevotella; Clostridiaceae; Clostridiales; Stroke
PubMed: 36430144
DOI: 10.3390/ijms232213665