Urinary TMAO Levels Are Associated with the Taxonomic Composition of the Gut Microbiota and with the Choline TMA-Lyase Gene (cutC) Harbored by Enterobacteriaceae

Gut microbiota metabolization of dietary choline may promote atherosclerosis through trimethylamine (TMA), which is rapidly absorbed and converted in the liver to proatherogenic trimethylamine-N-oxide (TMAO). The aim of this study was to verify whether TMAO urinary levels may be associated with the fecal relative abundance of specific bacterial taxa and the bacterial choline TMA-lyase gene cutC. The analysis of sequences available in GenBank grouped the cutC gene into two main clusters, cut-Dd and cut-Kp. A quantitative real-time polymerase chain reaction (qPCR) protocol was developed to quantify cutC and was used with DNA isolated from three fecal samples collected weekly over the course of three consecutive weeks from 16 healthy adults. The same DNA was used for 16S rRNA gene profiling. Concomitantly, urine was used to quantify TMAO by ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). All samples were positive for cutC and TMAO. Correlation analysis showed that the cut-Kp gene cluster was significantly associated with Enterobacteriaceae. Linear mixed models revealed that urinary TMAO levels may be predicted by fecal cut-Kp and by 23 operational taxonomic units (OTUs). Most of the OTUs significantly associated with TMAO were also significantly associated with cut-Kp, confirming the possible relationship between these two factors. In conclusion, this preliminary method-development study suggests the existence of a relationship between TMAO excreted in urine, specific fecal bacterial OTUs, and a cutC subgroup ascribable to the choline-TMA conversion enzymes of Enterobacteriaceae.

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The Effects of Genetic Relatedness on the Preterm Infant Gut Microbiota

Microorganisms ◽

10.3390/microorganisms9020278 ◽

2021 ◽

Vol 9 (2) ◽

pp. 278

Author(s):

Shen Jean Lim ◽

Miriam Aguilar-Lopez ◽

Christine Wetzel ◽

Samia V. O. Dutra ◽

Vanessa Bray ◽

...

Keyword(s):

Gut Microbiota ◽

Preterm Infant ◽

Neonatal Intensive Care ◽

Genetic Relatedness ◽

Bovine Milk ◽

Alpha Diversity ◽

Neonatal Intensive Care Units ◽

Rrna Gene ◽

Microbial Composition ◽

Operational Taxonomic Units

The preterm infant gut microbiota is influenced by environmental, endogenous, maternal, and genetic factors. Although siblings share similar gut microbial composition, it is not known how genetic relatedness affects alpha diversity and specific taxa abundances in preterm infants. We analyzed the 16S rRNA gene content of stool samples, ≤ and >3 weeks postnatal age, and clinical data from preterm multiplets and singletons at two Neonatal Intensive Care Units (NICUs), Tampa General Hospital (TGH; FL, USA) and Carle Hospital (IL, USA). Weeks on bovine milk-based fortifier (BMF) and weight gain velocity were significant predictors of alpha diversity. Alpha diversity between siblings were significantly correlated, particularly at ≤3 weeks postnatal age and in the TGH NICU, after controlling for clinical factors. Siblings shared higher gut microbial composition similarity compared to unrelated individuals. After residualizing against clinical covariates, 30 common operational taxonomic units were correlated between siblings across time points. These belonged to the bacterial classes Actinobacteria, Bacilli, Bacteroidia, Clostridia, Erysipelotrichia, and Negativicutes. Besides the influence of BMF and weight variables on the gut microbial diversity, our study identified gut microbial similarities between siblings that suggest genetic or shared maternal and environmental effects on the preterm infant gut microbiota.

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The impact of human-facilitated selection on the gut microbiota of domesticated mammals

FEMS Microbiology Ecology ◽

10.1093/femsec/fiz121 ◽

2019 ◽

Vol 95 (9) ◽

Cited By ~ 8

Author(s):

Giulia Alessandri ◽

Christian Milani ◽

Leonardo Mancabelli ◽

Marta Mangifesta ◽

Gabriele Andrea Lugli ◽

...

Keyword(s):

Gut Microbiota ◽

Horizontal Transmission ◽

Taxonomic Composition ◽

Functional Adaptation ◽

Rrna Gene ◽

Feed Conversion ◽

Shotgun Metagenomics ◽

Domesticated Animals ◽

And Behavior ◽

The Impact

ABSTRACT Domestication is the process by which anthropogenic forces shape lifestyle and behavior of wild species to accommodate human needs. The impact of domestication on animal physiology and behavior has been extensively studied, whereas its effect on the gut microbiota is still largely unexplored. For this reason, 16S rRNA gene-based and internal transcribed spacer-mediated bifidobacterial profiling, together with shotgun metagenomics, was employed to investigate the taxonomic composition and metabolic repertoire of 146 mammalian fecal samples, corresponding to 12 domesticated–feral dyads. Our results revealed that changes induced by domestication have extensively shaped the taxonomic composition of the mammalian gut microbiota. In this context, the selection of microbial taxa linked to a more efficient feed conversion into body mass and putative horizontal transmission of certain bacterial genera from humans were observed in the fecal microbiota of domesticated animals when compared to their feral relatives and to humans. In addition, profiling of the metabolic arsenal through metagenomics highlighted extensive functional adaptation of the fecal microbial community of domesticated mammals to changes induced by domestication. Remarkably, domesticated animals showed, when compared to their feral relatives, increased abundance of specific glycosyl hydrolases, possibly due to the higher intake of complex plant carbohydrates typical of commercial animal feeds.

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The impacts of deglaciation and human activity on the taxonomic structure of prokaryotic communities in Antarctic soils on King George Island

Antarctic Science ◽

10.1017/s095410201800024x ◽

2018 ◽

Vol 30 (5) ◽

pp. 278-288 ◽

Cited By ~ 3

Author(s):

E.V. Pershina ◽

E.A. Ivanova ◽

E.V. Abakumov ◽

E.E. Andronov

Keyword(s):

Bacterial Species ◽

Taxonomic Composition ◽

South Shetland Islands ◽

Soil Microbiome ◽

Taxonomic Structure ◽

Rrna Gene ◽

King George Island ◽

Antarctic Soils ◽

Operational Taxonomic Units ◽

Taxonomic Analysis

AbstractThe soil microbiome was investigated at environmentally distinct locations on King George Island in the South Shetland Islands (Antarctic Peninsula) using 16 S rRNA gene pyrosequencing. The taxonomic composition of the soil prokaryotes (bacteria and archaea) was evaluated at three sites representing human-disturbed soils (Bellingshausen Station) and soils undergoing different stages of deglaciation (fresh and old moraines located near Ecology Glacier). The taxonomic analysis revealed 20 bacterial and archaeal phyla, among which Proteobacteria (29.6%), Actinobacteria (25.3%), Bacteroidetes (15.8%), Cyanobacteria (11.2%), Acidobacteria (4.9%) and Verrucomicrobia (4.5%) comprised most of the microbiome. In a beta-diversity analysis, the samples formed separate clusters. The Bellingshausen Station samples were characterized by an increased amount ofNostocsp. andJanibactersp. Although the deglaciation history had less of an effect on the soil microbiome, the early stages of deglaciation (Sample 1) had a higher proportion of bacteria belonging to the families Xanthomonadaceae, Sphingomonadaceae and Nocardioidaceae, whereas the older moraines (Sample 2) were enriched with Chthoniobacteriacae and N1423WL. Solirubrobacteriales, Gaiellaceae and Chitinophagaceae bacteria were present in both stages of deglaciation, characterized by genus-level differences. Taxonomic analysis of the abundant operational taxonomic units (OTUs) revealed both endemic (Marisediminicola antarctica,Hymenobacter glaciei) and cosmopolitan bacterial species in the microbiomes.

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Interactions between the Gut Microbiome and Mucosal Immunoglobulins A, M, and G in the Developing Infant Gut

mSystems ◽

10.1128/msystems.00612-19 ◽

2019 ◽

Vol 4 (6) ◽

Cited By ~ 5

Author(s):

Anders Janzon ◽

Julia K. Goodrich ◽

Omry Koren ◽

Jillian L. Waters ◽

Ruth E. Ley

Keyword(s):

Gut Microbiome ◽

Immunoglobulin A ◽

Gene Profiling ◽

Rrna Gene ◽

Bacterial Cells ◽

Future Health ◽

Operational Taxonomic Units ◽

Single Location ◽

Infant Gut Microbiome ◽

Antibody Coating

ABSTRACT Interactions between the gut microbiome and immunoglobulin A (IgA) in the gut during infancy are important for future health. IgM and IgG are also present in the gut; however, their interactions with the microbiome in the developing infant remain to be characterized. Using stool samples sampled 15 times in infancy from 32 healthy subjects at 4 locations in 3 countries, we characterized patterns of microbiome development in relation to fecal levels of IgA, IgG, and IgM. For 8 infants from a single location, we used fluorescence-activated cell sorting of microbial cells from stool by Ig-coating status over 18 months. We used 16S rRNA gene profiling on full and sorted microbiomes to assess patterns of antibody coating in relation to age and other factors. All antibodies decreased in concentration with age but were augmented by breastmilk feeding regardless of infant age. Levels of IgA correlated with relative abundances of operational taxonomic units (OTUs) belonging to the Bifidobacteria and Enterobacteriaceae, which dominated the early microbiome, and IgG levels correlated with Haemophilus. The diversity of Ig-coated microbiota was influenced by breastfeeding and age. IgA and IgM coated the same microbiota, which reflected the overall diversity of the microbiome, while IgG targeted a different subset. Blautia generally evaded antibody coating, while members of the Bifidobacteria and Enterobacteriaceae were high in IgA/M. IgA/M displayed similar dynamics, generally coating the microbiome proportionally, and were influenced by breastfeeding status. IgG only coated a small fraction of the commensal microbiota and differed from the proportion targeted by IgA and IgM. IMPORTANCE Antibodies are secreted into the gut and attach to roughly half of the trillions of bacterial cells present. When babies are born, the breastmilk supplies these antibodies until the baby’s own immune system takes over this task after a few weeks. The vast majority of these antibodies are IgA, but two other types, IgG and IgM, are also present in the gut. Here, we ask if these three different antibody types target different types of bacteria in the infant gut as the infant develops from birth to 18 months old and how patterns of antibody coating of bacteria change with age. In this study of healthy infant samples over time, we found that IgA and IgM coat the same bacteria, which are generally representative of the diversity present, with a few exceptions that were more or less antibody coated than expected. IgG coated a separate suite of bacteria. These results provide a better understanding of how these antibodies interact with the developing infant gut microbiome.

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Altered Gut Microbiota Taxonomic Compositions of Patients With Sepsis in a Pediatric Intensive Care Unit

Frontiers in Pediatrics ◽

10.3389/fped.2021.645060 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jing Liu ◽

Mingbang Wang ◽

Weiming Chen ◽

Jian Ma ◽

Yi Peng ◽

...

Keyword(s):

Intensive Care ◽

Gut Microbiota ◽

Pathogenic Bacteria ◽

Pediatric Intensive Care ◽

16S Rrna Gene Sequencing ◽

Taxonomic Composition ◽

Rrna Gene ◽

Healthy Children ◽

Commensal Flora ◽

Opportunistic Pathogenic

Background: The gut is thought to play an important role in the pathogenesis of sepsis. Changes in the gut microbiota are closely related to the occurrence and development of human diseases, but few studies have focused on taxonomic composition of gut microbiota in septic patients. Knowledge of changes in the gut microbiota is a key issue in intensive care. Clinicians must understand how an altered gut microbiota affects the susceptibility and prognosis of septic patients.Measurements and Main Results: In the single-center case control study, 20 septic patients and 20 healthy children were recruited. The taxonomic composition of gut microbiota was determined via 16S rRNA gene sequencing. Gut microbiota diversity in children with sepsis was significantly reduced compared with that in healthy children. The taxonomic composition of gut microbiota can effectively distinguish children with sepsis from healthy children. Thirteen taxa of gut microbiota were significantly increased in the guts of children with sepsis compared with those of healthy children. The increased abundances of Enterococcaceae, Enterococcus, and Enterococcus durans in gut of septic patients were significantly positively correlated with blood inflammation indicators CRP and WBC. The abundances of seven bacteria were significantly decreased in the guts of septic children compared with those of healthy children. The decreased abundance of Bifidobacteriales in gut of septic patients is significantly negatively correlated with blood inflammation index WBC. A machine-learning classifier was built for distinguishing sepsis and achieved the AUC value of 81.25%. It shows that the composition of gut microbiota has certain potential for diagnosis of sepsis.Conclusions: Gut microbiota alterations in septic patients exhibit proliferation of opportunistic pathogenic bacteria, the massive reduction of the commensal flora, and the significant decrease in the diversity of the gut microbiota. Dysbiosis may also account for some changes in the inflammation indexes.

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Changes in gut microbiota composition and their associations with cortisol, melatonin and interleukin 6 in patients with chronic insomnia

Bulletin of Russian State Medical University ◽

10.24075/brsmu.2021.017 ◽

2021 ◽

Author(s):

AA Masyutina ◽

LN Gumenyuk ◽

YuV Fatovenko ◽

LE Sorokina ◽

SS Bayramova ◽

...

Keyword(s):

Gut Microbiota ◽

Sleep Quality ◽

Healthy Volunteers ◽

16S Rrna Gene Sequencing ◽

Cross Sectional Study ◽

Taxonomic Composition ◽

Chronic Insomnia ◽

Control Group ◽

Rrna Gene ◽

Cross Sectional

The relationship between the gut microbiota and chronic insomnia remains understudied. The aim of this paper was to investigate changes in the taxonomic composition of the gut microbiota and their associations with the levels of cortisol, melatonin and IL6 in patients with chronic insomnia. Our comparative prospective cross-sectional study enrolled 55 patients with chronic insomnia, who formed the main group (female patients: 58.2%, male patients: 41.8%; mean age 31.6 ± 7.4 years), and 50 healthy volunteers, who comprised the control group (females: 68.0%, males: 32.0%; mean age 33.2 ± 6.6 years). The taxonomic composition of the gut microbiota was profiled using 16S rRNA gene sequencing. Plasma cortisol and IL 6 and urine melatonin were measured by means of ELISA. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). In patients with chronic insomnia, the abundance of Faecalibacterium (p = 0.048), Prevotella 9 (p < 0.001) and Lachnospira (p = 0.036) was lower, whereas the abundance of Blautia (p = 0.012) and Eubacteriumhallii (p = 0.003) was higher than in healthy volunteers. Significant correlations were established between the levels of IL6 and the abundance of Faecalibacterium (r = –0.44; p = 0.001) and Blautia (r = 0.42; p < 0.001), as well as between cortisol concentrations and the abundance of Lachnospira (r = –0.41; p = 0.048). The abundance of Faecalibacterium and Blautiaс was correlated with higher PSQI (r = –0.47, p = 0.001; r = 0.45, p < 0.001, respectively). Our study contributed to the pool of data about changes in the gut microbiota and their associations with some endocrine and inflammation markers in patients with chronic insomnia. These data can be exploited to propose new strategies for the diagnosis and personalized treatment of insomnia aimed at normalizing the patient’s gut microbiota.

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Impact of a Multistrain Probiotic Formulation with High Bifidobacterial Content on the Fecal Bacterial Community and Short-Chain Fatty Acid Levels of Healthy Adults

Microorganisms ◽

10.3390/microorganisms8040492 ◽

2020 ◽

Vol 8 (4) ◽

pp. 492 ◽

Cited By ~ 3

Author(s):

Giorgio Gargari ◽

Valentina Taverniti ◽

Ranjan Koirala ◽

Claudio Gardana ◽

Simone Guglielmetti

Keyword(s):

Scientific Evidence ◽

Operational Taxonomic Unit ◽

Taxonomic Composition ◽

Healthy Adults ◽

Gene Profiling ◽

Rrna Gene ◽

Bifidobacterium Animalis ◽

Colony Forming Units ◽

Fecal Bacterial Community ◽

Acetate Butyrate

The consumption of probiotic products is continually increasing, supported by growing scientific evidence of their efficacy. Considering that probiotics may primarily affect health (either positively or negatively) through gut microbiota modulation, the first aspect that should be evaluated is their impact on the intestinal microbial ecosystem. In this study, we longitudinally analyzed the bacterial taxonomic composition and organic acid levels in four fecal samples collected over the course of four weeks from 19 healthy adults who ingested one capsule a day for two weeks of a formulation containing at least 70 billion colony-forming units, consisting of 25% lactobacilli and 75% Bifidobacterium animalis subsp. lactis. We found that 16S rRNA gene profiling showed that probiotic intake only induced an increase in a single operational taxonomic unit ascribed to B. animalis, plausibly corresponding to the ingested bifidobacterial strain. Furthermore, liquid chromatography/mass spectrometry revealed a significant increase in the lactate and acetate/butyrate ratio and a trend toward a decrease in succinate following probiotic administration. The presented results indicate that the investigated probiotic formulation did not alter the intestinal bacterial ecosystem of healthy adults and suggest its potential ability to promote colonization resistance in the gut through a transient increase in fecal bifidobacteria, lactic acid, and the acetate/butyrate ratio.

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Effects of functional pasta ingredients on different gut microbiota as revealed by TIM-2 in vitro model of the proximal colon

Beneficial Microbes ◽

10.3920/bm2018.0088 ◽

2019 ◽

Vol 10 (3) ◽

pp. 301-313

Author(s):

A. Martina ◽

G.E. Felis ◽

M. Corradi ◽

C. Maffeis ◽

S. Torriani ◽

...

Keyword(s):

Gut Microbiota ◽

In Vitro Model ◽

Bacillus Coagulans ◽

Proximal Colon ◽

Gene Profiling ◽

Rrna Gene ◽

Dietary Interventions ◽

Vitro Model ◽

Microbial Groups

Diet-related modulation of gut microbiota and its metabolic activity represents an intriguing research context, particularly in the case of disorders related to imbalances in gut microbial communities. We here explored the effects of Bacillus coagulans GBI-30, 6086 (BC30), β-glucans, and innovative whole-grain pastas, with or without these functional ingredients, on gut microbiota from three groups of children, presenting different susceptibility to type 1 diabetes, by using the well-controlled TNO in vitro model of the proximal colon (TIM-2). Short- and branched-chain fatty acids production and microbiota composition were assessed by means of gas chromatography and 16S rRNA gene profiling, respectively. In most cases, in vitro dietary interventions caused microbiota-dependent modulations as a result of intergroup variability, but also specific changes in microbial groups were shared between the three microbiotas, highlighting specific diet-microbial taxa connections.

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Production of conjugated linoleic acid (CLA): effect of inulin on microbial composition and CLA concentration in a human intestinal model

Proceedings of The Nutrition Society ◽

10.1017/s0029665120005777 ◽

2020 ◽

Vol 79 (OCE2) ◽

Author(s):

Ilaria Carafa ◽

Domenico Masuero ◽

Urska Vrhovsek ◽

Giovanni Bittante ◽

Elena Franciosi ◽

...

Keyword(s):

Linoleic Acid ◽

Gut Microbiota ◽

Relative Abundance ◽

Illumina Miseq ◽

Ultra Performance Liquid Chromatography ◽

Rrna Gene ◽

Human Gut ◽

Microbial Composition ◽

Human Gut Microbiota

AbstractConjugated linoleic acids (CLAs) show a number of putative health-promoting activities including anti-carcinogenic, anti-adipogenic, anti-diabetogenic, anti-inflammatory and antioxidant actions. CLAs are naturally produced by ruminal bacteria and several studies demonstrate that various lactobacilli and bifidobacteria are also able to produce CLAs in vitro from linoleic acid (LA). However, the ability of the human gut microbiota to produce CLA is less extensively studied. Our hypothesis is that the human gut microbiota is able to convert LA to CLA, and that the readily fermentable fiber inulin would positively modulate the growth of CLA-producing bacteria and, consequently increase the CLA content in the intestine.The capability of the faecal microbiota from five healthy donors to produce CLA was tested in anaerobic batch cultures for 48 hours at pH 5.5 and 6.5. Test treatments were linoleic acid (LA; 1 mg/mL) + bovine serum albumin (BSA; 0.2 mg/mL), and LA (1 mg/mL) + BSA (0.2 mg/mL) + inulin (1%, w/v) compared to a control BSA (0.2 mg/mL) fermentation. The microbial composition was analyzed 0, 24 and 48 hours after starting the fermentation by 16S rRNA gene Illumina MiSeq sequencing (V3-V4 region). CLAs were quantified by Ultra performance liquid chromatography - tandem mass spectrometer (UPLC-MS/MS) and bi-dimensional gas chromatography (GC x GC).The inclusion of LA + BSA + inulin at pH 5.5 significantly increased the relative abundance of Collinsella aerofaciens (p < 0.05), and tended to increase the relative abundance of bifidobacteria. LA + BSA + inulin at both pH 5.5 and 6.5 reduced the relative abundance of Parabacteroides, Bilophila, Clostridia and Enterobacteriaceae (p < 0.05). The concentration of CLA, in particular the isomer cis9,trans11 C18:2, was significantly higher in the LA + BSA + inulin group at pH 5.5 after 24 and 48 hours fermentation.The data show that the treatment LA + BSA + inulin at pH 5.5 induce substantial changes in microbiota composition, including bifidogenesis and CLA production in a human intestinal microbiota model. The changes of relative abundance detected are consistent with changes in gut bacteria previously linked to human health. Collinsella aerofaciens has been reported for reducing bloating, in particular in subjects suffering from irritable bowel syndrome, while Clostridia, Bilophila and Enterobacteriaceae causes human infections. In addition, the increase of bifidobacteria and LAB, which have previously been shown in vitro to produce CLA, may also be involved in CLA production under simulated cecal microbiome. These preclinical observations warrant confirmation in suitably designed animal and human mechanistic studies.

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Host Species Determines the Composition of the Prokaryotic Microbiota in Phlebotomus Sandflies

Pathogens ◽

10.3390/pathogens9060428 ◽

2020 ◽

Vol 9 (6) ◽

pp. 428

Author(s):

Christos Papadopoulos ◽

Panagiotis A. Karas ◽

Sotirios Vasileiadis ◽

Panagiota Ligda ◽

Anastasios Saratsis ◽

...

Keyword(s):

Gut Microbiota ◽

Host Species ◽

Archaeal Community ◽

Amplicon Sequencing ◽

Structural Effect ◽

Rrna Gene ◽

Host Genotype ◽

Operational Taxonomic Units ◽

Phlebotomine Sandflies ◽

Leishmania Spp

Phlebotomine sandflies are vectors of the humans’ and mammals’ parasite Leishmania spp. Although the role of gut microbiome in the biological cycle of insects is acknowledged, we still know little about the factors modulating the composition of the gut microbiota of sandflies. We tested whether host species impose a strong structural effect on the gut microbiota of Phlebotomus spp. Sandflies were collected from the island of Leros, Greece, and classified to P. papatasi, P. neglectus, P. tobbi, and P. similis, all being negative to Leishmania spp. The prokaryotic gut microbiota was determined via 16S rRNA gene amplicon sequencing. Phlebotomus species supported distinct microbial communities (p < 0.001). P. papatasi microbiota was the most distinct over-dominated by three Spiroplasma, Wolbachia and Paenibacillus operational taxonomic units (OTUs), while another Wolbachia OTU prevailed in P. neglectus. Conversely, the microbiota of P. tobbi and P. similis was composed of several less dominant OTUs. Archaea showed low presence with the dominant OTUs belonging to methanogenic Euryarcheota, ammonia-oxidizing Thaumarcheota, and Nanoarchaeota. We provide first insights into the composition of the bacterial and archaeal community of Phlebotomus sandflies and showed that, in the absence of Leishmania, host genotype is the major modulator of Phlebotomus sandfly gut microbiota.

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