Gene Kim’s research while affiliated with Cedars-Sinai Medical Center and other places

... Uprkos nedostatku konsenzusa o razlikama u crevnom mikrobiomu između pacijenata sa IC i zdrave populacije, specifične mikrobne promene koreliraju sa ishodom bolesti i to je pokazano prethodnim molekularnim metodama koje opisuju obilje Gram-negativnih bakterija u mikrobiomu tankog creva pacijenata sa IC 34,35 . Studije koje su ispitivale fekalne uzorke potvrdile su smanjenje vrsta iz roda Bifidobacterium i Lactobacillus, a sa druge strane, povećano prisustvo Firmicutes/Bacteroidetes. ...

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The role of the connection between intestinal microbiota and brain in the pathogenesis of functional gastrointestinal disorders

... 4,11 Increased understanding of the pathophysiology of IBS by the lead author and others has helped lead to the development of a novel IBS diagnostic blood panel (Commonwealth Laboratories, Inc, Salem, MA). [18][19][20][21][22][23][24] The biomarker consists of a simple blood test measurement of circulating antibodies to cytolethal distending toxin B (anti-CdtB) and vinculin (antivinculin). Studies in a postinfectious animal model have shown that an IBS-like phenotype was produced when host antibodies to CdtB cross-reacted with vinculin in the host gut. 25 This IBS diagnostic blood panel was recently validated in a large study that enrolled patients with IBS-D (n ¼ 2375), IBD (n ¼ 142), or celiac disease (n ¼ 121) and healthy control subjects (n ¼ 43). ...

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A Predictive Model to Estimate Cost Savings of a Novel Diagnostic Blood Panel for Diagnosis of Diarrhea-predominant Irritable Bowel Syndrome

... Further, rats which gained most weight were those with the most bowel segments colonized with M. smithii, irrespective of whether or not they were on high-fat chow (23). An important aspect of this study was that it demonstrated M. smithii colonization throught the small intestine, a finding we later confirmed in human duodenal samples (25). This was significant as M. smithii had previously been thought to only colonize the large intestine, weakening the likelihood that it could play a significant role in caloric harvest and weight gain. ...

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Metabolic Effects of Eradicating Breath Methane using Antibiotics in Prediabetic Subjects with Obesity

... Treatment with lovastatin lactone resulted in a significant reduction in M. smithii levels in the distal small bowel (ileum), and treatment with lovastatin hydroxyacid resulted in looser stools, when compared to rats maintained on the HFD, indicating that inhibiting methanogens resulted in normalization of % wet weights away from the constipation-like phenotype. Of note, while methanogens are typically most abundant in the colon in humans, we have previously demonstrated high abundance of methanogens in the small intestine, both in rats [12] and in some human subjects [27]. These findings suggest that increased levels of methanogens, particularly M. smithii, directly contribute to a constipation phenotype in subjects with IBS-C. ...

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Hydrogen Sulfide Producers Drive a Diarrhea-Like Phenotype and a Methane Producer Drives a Constipation-Like Phenotype in Animal Models

... 8,10 Furthermore, the development of antibodies to CdtB was associated with altering gut microbiota associated with reducing specific interstitial cells of Cajal (ICC). 11,12 These findings are possibly due to the ability of anti-CdtB to cross-react with the host cell adhesion protein vinculin present in interstitial cells of Cajal and the myenteric ganglia that control the normal activity of the intestinal tract, including phase III of inter-digestive motor activity. 13 Absence or decrease in phase III contractions results in small intestinal bacterial overgrowth in animal models and human patients with IBS. ...

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Study of Antibodies to Cytolethal Distending Toxin B (CdtB) and Antibodies to Vinculin in Patients with Irritable Bowel Syndrome

... Following from this, methane producers also had worse glucose tolerance compared to nonmethane producers 83 , and pharmacologically reducing breath methane (through antibiotic use) in obese patients improved glucose tolerance 84 . Patients who were positive for both methane and hydrogen also displayed reduced (prorated) percentage changes in BMI following bariatric surgery 85 . ...

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Beyond the Gut: Unveiling Methane’s Role in Broader Physiological Systems

... A recent study showed that using a single--lumen catheter to aspirate small bowel fluid resulted in a 19.6% contamination rate (25) . Furthermore, only 40% of the total gut flora can be identified using conventional culture methods (26) . Not all hydrogen-producing bacteria are culturable, and some microbiology laboratories are not able to culture methanogenic archaea (27) . ...

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DIAGNOSIS AND TREATMENT OF SMALL INTESTINAL BACTERIAL OVERGROWTH: AN OFFICIAL POSITION PAPER FROM THE BRAZILIAN FEDERATION OF GASTROENTEROLOGY

... Among adults only, methane excretion was significantly associated with constipation (OR = 3.47; 95% CI, 1.84-6.54). As shown by Kim et al, 85 the responsible strain in these patients was the M. smithii. The combination of rifaximin plus neomycin proved to be effective in these cases. ...

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Intestinal Microbiota Its Role in Digestive Diseases

... Some evidence supports that methanogens have an impact on host metabolism in mouse models [11]. For example, mice inoculated with methanogens showed increased weight and adiposity despite consuming the same amount of food as controls [21,22]. However, the role of methanogens in human metabolism is complicated and controversial. ...

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Methanogens are associated with altered microbial production of short-chain fatty acids and human-host metabolizable energy

... The research results of Lauritano et al. showed that the overall incidence of adverse events of rifaximin was significantly lower than that of metronidazole group, showing that the side effects of non-absorbable antibiotics were less [154]. The results of a drug resistance study showed that the concentration of stool Staphylococcus spp and stool Coliforms would be temporarily reduced during the treatment of rifaximin [155]. Xu et al. showed that rifaximin changed the bacterial population in the ileum of rats, increasing the relative abundance of Lactobacillus, and preventing mucosal inflammation and impaired intestinal barrier [156]. ...

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Intestinal microbiota regulates the gut-thyroid axis: the new dawn of improving Hashimoto thyroiditis