Factors Associated with the Diversification of the Gut Microbial Communities within Chimpanzees from Gombe National Park.

The gastrointestinal tract harbors large and diverse populations of bacteria that vary among individuals and within individuals over time. Numerous internal and external factors can influence the contents of these microbial communities, including diet, geography, physiology, and the extent of contact among hosts. To investigate the contributions of such factors to the variation and changes in gut microbial communities, we analyzed the distal gut microbiota of individual chimpanzees from two communities in Gombe National Park, Tanzania. These samples, which were derived from 35 chimpanzees, many of whom have been monitored for multiple years, provide an unusually comprehensive longitudinal depth for individuals of known genetic relationships. Although the composition of the great-ape microbiota has been shown to codiversify with host species, indicating that host genetics and phylogeny have played a major role in its differentiation over evolutionary timescales, the geneaological relationships of individual chimpanzees did not coincide with the similarity in their gut microbial communities. However, the inhabitants from adjacent chimpanzee communities could be distinguished based on the contents of their gut microbiota. Despite the broad similarity of community members, as would be expected from shared diet or interactions, long-term immigrants to a community often harbored the most distinctive gut microbiota, suggesting that individuals retain hallmarks of their previous gut microbial communities for extended periods. This pattern was reinforced in several chimpanzees sampled over long temporal scales, in which the major constituents of the gut microbiota were maintained for nearly a decade

An experimental study on the air delivery and gas removal method in a model of furnace for ferroalloy production

In the paper, results of a model study on the effects of the air delivery and flue gas removal method on the intensity of gas blending in the hood space are presented. Two design solutions were compared: with one or two outlet channels for the hood gases. Moreover, two variants of air delivery through charging doors were analysed. The study results show that for technological reasons, more beneficial gasodynamic conditions are obtained when the hood is fitted with two symmetrically located gas outlet channels and the air is sucked through four charging doors

Social behavior shapes the chimpanzee pan-microbiome

Animal sociality facilitates the transmission of pathogenic microorganisms among hosts, but the extent to which sociality enables animals’ beneficial microbial associations is poorly understood. The question is critical because microbial communities, particularly those in the gut, are key regulators of host health. We show evidence that chimpanzee social interactions propagate microbial diversity in the gut microbiome both within and between host generations. Frequent social interaction promotes species richness within individual microbiomes as well as homogeneity among the gut community memberships of different chimpanzees. Sampling successive generations across multiple chimpanzee families suggests that infants inherited gut microorganisms primarily through social transmission. These results indicate that social behavior generates a pan-microbiome, preserving microbial diversity across evolutionary time scales and contributing to the evolution of host species–specific gut microbial communities

Experimental Fracture Model versus Osteotomy Model in Metacarpal Bone Plate Fixation

Introduction. Osteotomy or fracture models can be used to evaluate mechanical properties of fixation techniques of the hand skeleton in vitro. Although many studies make use of osteotomy models, fracture models simulate the clinical situation more realistically. This study investigates monocortical and bicortical plate fixation on metacarpal bones considering both aforementioned models to decide which method is best suited to test fixation techniques. Methods. Porcine metacarpal bones (n = 40) were randomized into 4 groups. In groups I and II bones were fractured with a modified 3-point bending test. The intact bones represented a further control group to which the other groups after fixation were compared. In groups III and IV a standard osteotomy was carried out. Bones were fixated with plates monocortically (group I, III) and bicortically (group II, IV) and tested for failure. Results. Bones fractured at a mean maximum load of 482.8 N ± 104.8 N with a relative standard deviation (RSD) of 21.7%, mean stiffness was 122.3 ± 35 N/mm. In the fracture model, there was a significant difference (P = 0.01) for maximum load of monocortically and bicortically fixed bones in contrast to the osteotomy model (P = 0.9). Discussion. In the fracture model, because one can use the same bone for both measurements in the intact state and the bone-plate construct states, the impact of inter-individual differences is reduced. In contrast to the osteotomy model there are differences between monocortical and bicortical fixations in the fracture model. Thus simulation of the in vivo situation is better and seems to be suitable for the evaluation of mechanical properties of fixation techniques on metacarpals

An unusual cause of ankle pain: fracture of a talocalcaneal coalition as a differential diagnosis in an acute ankle sprain: a case report and literature review

Background: The acute ankle sprain is one of the most common injuries seen in trauma departments. Ankle sprains have an incidence of about one injury per 10 000 people a day. In contrast tarsal coalition is a rare condition occurring in not more than one percent of the population. Case presentation: We present the case of a 23 year old male patient with pain and local swelling after an acute ankle sprain. Initial clinical and radiological examination showed no pathologies. Due to prolonged pain, swelling and the inability of the patient to weight bear one week after trauma further diagnostics was performed. Imaging studies (MRI and CT) revealed a fracture of a talocalcaneal coalition. To the knowledge of the authors no fracture of a coalition was reported so far. Conclusion: This report highlights the presentation of symptomatic coalitions following trauma and furthermore, it points out the difficulties in the diagnosis and treatment of a rare entity after a common injury. A diagnostic algorithm has been developed to ensure not to miss a severe injury.<br

An experimental gasodynamic study of a model of furnace for ferroalloy production

A gasodynamic study of a model of hood space was performed based on measurements of velocity and concentration distributions of gases. The experiments have shown that the absolute values of gas velocities in the hood and the outlet channel as well as their profiles do not depend on the negative pressure value in the channel. Location of ceiling nozzle outlets does not significantly affect the gasodynamic parameters of the hood space. Moreover, uniform distribution of the air, delivered through the ceiling nozzles, has been observed in the whole hood space, which creates conditions for afterburning of gaseous reaction products in this space

Cooperative effects in differentiation and proliferation between PDGF-BB and matrix derived synthetic peptides in human osteoblasts

Background: Enhancing osteogenic capabilities of bone matrix for the treatment of fractures and segmental defects using growth factors is an active area of research. Recently, synthetic peptides like AC- 100, TP508 or p-15 corresponding to biologically active sequences of matrix proteins have been proven to stimulate bone formation. The platelet-derived growth factor (PDGF) BB has been identified as an important paracrine factor in early bone healing. We hypothesized that the combined use of PDGF-BB with synthetic peptides could result in an increase in proliferation and calcification of osteoblast-like cells. Methods: Osteoblast-like cell cultures were treated with PDGF and synthetic peptides, singly and as combinations, and compared to non-treated control cell cultures. The cultures were evaluated at days 2, 5, and 10 in terms of cell proliferation, calcification and gene expression of alkaline phosphate, collagen I and osteocalcin. Results: Experimental findings revealed that the addition of PDGF, p-15 and TP508 and combinations of PDGF/AC-100, PDGF/p-15 and PDGF/TP508 resulted in an increase in proliferating osteoblasts, especially in the first 5 days of cultivation. Proliferation did not significantly differ between single factors and factor combinations (p > 0.05). The onset of calcification in osteoblasts occurred earlier and was more distinct compared to the corresponding control or PDGF stimulation alone. Significant difference was found for the combined use of PDGF/p-15 and PDGF/AC-100 (p < 0.05). Conclusions: Our findings indicate that PDGF exhibits cooperative effects with synthetic peptides in differentiation and proliferation. These cooperative effects cause a significant early calcification of osteoblast-like cells (p < 0.05). We suggest the combination of synthetic peptides and PDGF as a potential clinical approach for accelerating bone healing or coating osteosynthesis materials.

Microevolution of Helicobacter pylori during prolonged infection of single hosts and within families

Our understanding of basic evolutionary processes in bacteria is still very limited. For example, multiple recent dating estimates are based on a universal inter-species molecular clock rate, but that rate was calibrated using estimates of geological dates that are no longer accepted. We therefore estimated the short-term rates of mutation and recombination in Helicobacter pylori by sequencing an average of 39,300 bp in 78 gene fragments from 97 isolates. These isolates included 34 pairs of sequential samples, which were sampled at intervals of 0.25 to 10.2 years. They also included single isolates from 29 individuals (average age: 45 years) from 10 families. The accumulation of sequence diversity increased with time of separation in a clock-like manner in the sequential isolates. We used Approximate Bayesian Computation to estimate the rates of mutation, recombination, mean length of recombination tracts, and average diversity in those tracts. The estimates indicate that the short-term mutation rate is 1.4×10−6 (serial isolates) to 4.5×10−6 (family isolates) per nucleotide per year and that three times as many substitutions are introduced by recombination as by mutation. The long-term mutation rate over millennia is 5–17-fold lower, partly due to the removal of non-synonymous mutations due to purifying selection. Comparisons with the recent literature show that short-term mutation rates vary dramatically in different bacterial species and can span a range of several orders of magnitude

GOHTAM: a website for ‘Genomic Origin of Horizontal Transfers, Alignment and Metagenomics’

Motivation: This website allows the detection of horizontal transfers based on a combination of parametric methods and proposes an origin by researching neighbors in a bank of genomic signatures. This bank is also used to research an origin to DNA fragments from metagenomics studies