35 research outputs found

    Niche partitioning of a pathogenic microbiome driven by chemical gradients

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    © 2018 The Authors, some rights reserved. Environmental microbial communities are stratified by chemical gradients that shape the structure and function of these systems. Similar chemical gradients exist in the human body, but how they influence these microbial systems is more poorly understood. Understanding these effects can be particularly important for dysbiotic shifts in microbiome structure that are often associated with disease. We show that pH and oxygen strongly partition the microbial community from a diseased human lung into two mutually exclusive communities of pathogens and anaerobes. Antimicrobial treatment disrupted this chemical partitioning, causing complex death, survival, and resistance outcomes that were highly dependent on the individual microorganism and on community stratification. These effects were mathematically modeled, enabling a predictive understanding of this complex polymicrobial system. Harnessing the power of these chemical gradients could be a drug-free method of shaping microbial communities in the human body from undesirable dysbiotic states

    The Static Maxwell System in Three Dimensional Axially Symmetric Inhomogeneous Media and Axially Symmetric Generalization of the Cauchy–Riemann System

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    In this paper we discuss different generalizations of the Cauchy–Riemann system and their connection with the static Maxwell system. In particular, this allows us to present relations between slice-monogenic functions and hypermonogenic functions, as well as to provide a physical interpretation of slice-monogenic functions. Furthermore, we present an explicit and complete set of basic solutions of a new class of axial-hypermonogenic functions in R^3. In the end we determine the symmetry operators for the class of axial-hypermonogenic functions

    Diploids in the Cryptococcus neoformans Serotype A Population Homozygous for the α Mating Type Originate via Unisexual Mating

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    The ubiquitous environmental human pathogen Cryptococcus neoformans is traditionally considered a haploid fungus with a bipolar mating system. In nature, the α mating type is overwhelmingly predominant over a. How genetic diversity is generated and maintained by this heterothallic fungus in a largely unisexual α population is unclear. Recently it was discovered that C. neoformans can undergo same-sex mating under laboratory conditions generating both diploid intermediates and haploid recombinant progeny. Same-sex mating (α-α) also occurs in nature as evidenced by the existence of natural diploid αADα hybrids that arose by fusion between two α cells of different serotypes (A and D). How significantly this novel sexual style contributes to genetic diversity of the Cryptococcus population was unknown. In this study, ∼500 natural C. neoformans isolates were tested for ploidy and close to 8% were found to be diploid by fluorescence flow cytometry analysis. The majority of these diploids were serotype A isolates with two copies of the α MAT locus allele. Among those, several are intra-varietal allodiploid hybrids produced by fusion of two genetically distinct α cells through same-sex mating. The majority, however, are autodiploids that harbor two seemingly identical copies of the genome and arose via either endoreplication or clonal mating. The diploids identified were isolated from different geographic locations and varied genotypically and phenotypically, indicating independent non-clonal origins. The present study demonstrates that unisexual mating produces diploid isolates of C. neoformans in nature, giving rise to populations of hybrids and mixed ploidy. Our findings underscore the importance of same-sex mating in shaping the current population structure of this important human pathogenic fungus, with implications for mechanisms of selfing and inbreeding in other microbial pathogens

    Treatment of patients with ankle fractures. Use of Xarelto for the prevention of thromboembolic complications

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    The article tells about the results of analysis of treatment applied to patients with distal tibia fractures (transsyndesmotic malleolar fractures, 44-B type by AO classification, associated with rupture of the distal tibiofibular syndesmosis) and prevention of thromboembolic complications. Studies were carried out comparing conservative and surgical treatment of patients with ankle fractures; the treatment tactics was suggested, medicines used in the prevention of venous thromboembolic complications were compared. The obtained data demonstrates excellent results of surgery in case of no contraindications and high effectiveness of oral drugs for the prevention of thromboembolic complications

    Semi-rigid penile prosthesis as a salvage management of idiopathic ischemic stuttering priapism

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    Amr A Faddan, Alexey V Aksenov, Carsten M Naumann, Klaus P Jünemann, Daniar K Osmonov Department of Urology and Pediatric Urology, University Hospital Schleswig-Holstein, Kiel, Germany Introduction: Priapism is the persistent erection resulting from dysfunction of the mechanisms that regulate penile swelling, stiffness, and sagging. It is a full or partial erection that persists for a period more than 4 hours beyond sexual stimulation and/or orgasm or is unrelated to sexual stimulation. Ischemic priapism should be managed in a step-by-step fashion. Objective: To demonstrate step-by-step management of stuttering refractory ischemic priapism. We report a case of stuttering refractory ischemic priapism. Moreover, we reviewed different approaches to priapism management in the literature. Case presentation: A 53-year-old male presented with a painful erection of 29 hours’ duration, probably caused by consumption of alcohol. The penile blood gas showed a pH of 7.08, PCO2 of 75 mmHg and PO2 of 39 mmHg. Aspiration was followed by irrigation of an α-adrenergic, Winter and T-shunt operations were preformed, and finally a semi-rigid penile prosthesis was implanted to overcome the refractory stuttering ischemic priapism. Conclusion: In case of stuttering refractory ischemic priapism, immediate implantation of a penile prosthesis is a simple and effective procedure that manages both the acute episode and the inevitable erectile dysfunction that would otherwise occur, while preserving penile length. Keywords: priapism, stuttering priapism, shunting operation, penile prosthesis&nbsp

    Arthroscopic reconstruction of anterior cruciate ligament with hamstring tendon. Comparison of anticoagulation protocols

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    The article describes the arthroscopic reconstructive surgical technique for the correction of anterior cruciate ligament in the instability of the knee joint; the expected long-term results of plastic repair of the anterior cruciate ligament and results of own observations are presented; different protocols of prophylactic anticoagulation therapy in the early postoperative period are compared. The obtained data demonstrates comparable efficacy of tableted medicines and traditional injectable drug forms for the prevention of thromboembolic complications

    Group theoretic methods and similarity solutions of the Savage-Hutter equations

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    Abstract. We consider the spatially one-dimensional time dependent system of equations, obtained by Savage and Hutter, which describes the gravity-driven free surface flow of granular avalanches. All similarity solutions of this system are found by means of group analysis. The results of the computed experiments are reduced and their physical treatment is considered.

    Neutrophilic proteolysis in the cystic fibrosis lung correlates with a pathogenic microbiome

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    Background: Studies of the cystic fibrosis (CF) lung microbiome have consistently shown that lung function decline is associated with decreased microbial diversity due to the dominance of opportunistic pathogens. However, how this phenomenon is reflected in the metabolites and chemical environment of lung secretions remains poorly understood. Methods: Here we investigated the microbial and molecular composition of CF sputum samples using 16S rRNA gene amplicon sequencing and untargeted tandem mass spectrometry to determine their interrelationships and associations with clinical measures of disease severity. Results: The CF metabolome was found to exist in two states: one from patients with more severe disease that had higher molecular diversity and more Pseudomonas aeruginosa and the other from patients with better lung function having lower metabolite diversity and fewer pathogenic bacteria. The two molecular states were differentiated by the abundance and diversity of peptides and amino acids. Patients with severe disease and more pathogenic bacteria had higher levels of peptides. Analysis of the carboxyl terminal residues of these peptides indicated that neutrophil elastase and cathepsin G were responsible for their generation, and accordingly, these patients had higher levels of proteolytic activity from these enzymes in their sputum. The CF pathogen Pseudomonas aeruginosa was correlated with the abundance of amino acids and is known to primarily feed on them in the lung. Conclusions: In cases of severe CF lung disease, proteolysis by host enzymes creates an amino acid-rich environment that P. aeruginosa comes to dominate, which may contribute to the pathogen's persistence by providing its preferred carbon source
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