Microbiota of the Colonic Diverticula in the Complicated Form of Diverticulitis: A Case Report.

Intestinal microbiota appears to be implicated in the pathogenesis of diverticular disease. We present the case of a patient with diverticular colon disease complicated by a pelvic abscess. During the successful surgical treatment, two specimens were taken from the resected colon segment for the microbiota analysis: an inflamed and perforated diverticulum and a diverticulum without signs of inflammation. Culturing and 16S rRNA gene sequencing revealed significant changes in the microbial community structure and composition associated with the acute inflammation and perforation of the colonic diverticulum. The characteristics that are usually associated with the inflammatory process in the gut, namely reduced microbial diversity and richness, decreased Firmicutes-to-Bacteroidetes (F/B) ratio, depletion of butyrate-producing bacteria, and Enterobacteriaceae blooming, were more pronounced in the non-inflamed diverticulum rather than in the adjacent inflamed and perforated one. This is the first study of the intraluminal microbiota of the diverticular pockets, which is more relevant to the etiology of diverticular disease than mucosa-associated microbiota via biopsies and luminal microbiota via fecal samples.

Classification of ballpoint pen inks based on selective extraction and subsequent digital color and cluster analyses.

Here, we propose a novel approach to the classification of blue ballpoint pen inks based on a combination of selective extraction of coloring components from a paper carrier, digital color analysis (DCA) of the remaining traces, and hierarchical cluster analysis of DCA results. Since most documents of high importance are still produced in hard copies, the proposed method, being highly time- and cost-efficient, could be a significant contribution to forensic science in the field of authenticating handwritten documents. Several commonly used solvents were applied in parallel as extractants to the replicate strokes produced by each pen. It turned out to be possible to limit the number of extractants required for an unambiguous classification to three. We have shown that the optimal descriptor for agglomerative clustering is the colorimetric distance between the original and extracted ink traces in the RGB color space. Five separate clusters of inks that are independent of sample storage temperature were obtained from a set of 16 different pens. This conclusion was further confirmed by the analysis of principal components. The developed DCA-based data processing pipeline outperformed the clustering based on the data of high-performance liquid chromatography in terms of versatility providing a more informative analysis with respect to the inks based on the phthalocyanine dyes.

Characterization of gut contractility and microbiota in patients with severe chronic constipation.

Chronic constipation (CC) is one of the most common gastrointestinal disorders worldwide. Its pathogenesis, however, remains largely unclear. The purpose of the present work was to gain an insight into the role of contractility and microbiota in the etiology of CC. To this end, we studied spontaneous and evoked contractile activity of descending colon segments from patients that have undergone surgery for refractory forms of CC. The juxta-mucosal microbiota of these colon samples were characterized with culture-based and 16S rRNA sequencing techniques. In patients with CC the spontaneous colonic motility remained unchanged compared to the control group without dysfunction of intestinal motility. Moreover, contractions induced by potassium chloride and carbachol were increased in both circular and longitudinal colonic muscle strips, thus indicating preservation of contractile apparatus and increased sensitivity to cholinergic nerve stimulation in the constipated intestine. In the test group, the gut microbiota composition was assessed as being typically human, with four dominant bacterial phyla, namely Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria, as well as usual representation of the most prevalent gut bacterial genera. Yet, significant inter-individual differences were revealed. The phylogenetic diversity of gut microbiota was not affected by age, sex, or colonic anatomy (dolichocolon, megacolon). The abundance of butyrate-producing genera Roseburia, Coprococcus, and Faecalibacterium was low, whereas conventional probiotic genera Lactobacillus and Bifidobacteria were not decreased in the gut microbiomes of the constipated patients. As evidenced by our study, specific microbial biomarkers for constipation state are absent. The results point to a probable role played by the overall gut microbiota at the functional level. To our knowledge, this is the first comprehensive characterization of CC pathogenesis, finding lack of disruption of motor activity of colonic smooth muscle cells and insufficiency of particular members of gut microbiota usually implicated in CC.