Vestium or Ruthenium – What Does a Study of the Literature Tell Us?

The process of the discovery of the sixth new element and metal present in raw platinum ore granules, and called vestium or ruthenium, took place between 1807 and 1844. The element was first discovered by the Polish chemist and medical doctor, J?drzej ?niadecki, professor at Vilnius University, presently Lithuania. It took almost 40 years to confirm the discovery by two German chemists working in Russia, Gottfried Osann and Carl Ernst Claus, who had at their disposition platinum ore recently discovered in the Ural Mountains. The discovery work of J?drzej ?niadecki was supported by his older brother Jan ?niadecki, a noted mathematician and astronomer, who was also the Rector of Vilnius University at the time of the original discovery. ?niadecki brothers were educated in Poland (Pozna? and Cracow) and abroad: J?drzejin Pavia (Italy), Edinburgh (Scotland) and Vienna, and Janin Göttingen, Leiden, Utrecht and prerevolutionary Paris

An Aberrant Microbiota is not Strongly Associated with Incidental Colonic Diverticulosis

Colonic diverticula are protrusions of the mucosa through weak areas of the colonic musculature. The etiology of diverticulosis is poorly understood, but could be related to gut bacteria. Using mucosal biopsies from the sigmoid colon of 226 subjects with and 309 subjects without diverticula during first-time screening colonoscopy, we assessed whether individuals with incidental colonic diverticulosis have alternations in the adherent bacterial communities in the sigmoid colon. We found little evidence of substantial associations between the microbial community and diverticulosis among cases and controls. Comparisons of bacterial abundances across all taxonomic levels showed differences for phylum Proteobacteria (p = 0.038) and family Comamonadaceae (p = 0.035). The r-squared values measuring the strength of these associations were very weak, however, with values ~2%. There was a similarly small association between the abundance of each taxa and total diverticula counts. Cases with proximal only diverticula and distal only diverticula likewise showed little difference in overall microbiota profiles. This large study suggests little association between diverticula and the mucosal microbiota overall, or by diverticula number and location. We conclude that the mucosal adherent microbiota community composition is unlikely to play a substantial role in development of diverticulosis

Sequence variant analysis reveals poor correlations in microbial taxonomic abundance between humans and mice after gnotobiotic transfer

Transplanting human gut microbiotas into germ-free (GF) mice is a popular approach to disentangle cause-and-effect relationships between enteric microbes and disease. Algorithm development has enabled sequence variant (SV) identification from 16S rRNA gene sequence data. SV analyses can identify which donor taxa colonize recipient GF mice, and how SV abundance in humans is replicated in these mice. Fecal microbiotas from 8 human subjects were used to generate 77 slurries, which were transplanted into 153 GF mice. Strong correlations between fecal and slurry microbial communities were observed; however, only 42.15 ± 9.95% of SVs successfully transferred from the donor to the corresponding recipient mouse. Firmicutes had a particularly low transfer rate and SV abundance was poorly correlated between donor and recipient pairs. Our study confirms human fecal microbiotas colonize formerly GF mice, but the engrafted community only partially resembles the input human communities. Our findings emphasize the importance of reporting a standardized transfer rate and merit the exploration of other animal models or in silico tools to understand the relationships between human gut microbiotas and disease