Complex Microbiome Underlying Secondary and Primary Metabolism in the Tunicate-\u3cem\u3eProchloron\u3c/em\u3e Symbiosis

The relationship between tunicates and the uncultivated cyanobacterium Prochloron didemni has long provided a model symbiosis. P. didemni is required for survival of animals such as Lissoclinum patella and also makes secondary metabolites of pharmaceutical interest. Here, we present the metagenomes, chemistry, and microbiomes of four related L. patella tunicate samples from a wide geographical range of the tropical Pacific. The remarkably similar P. didemni genomes are the most complex so far assembled from uncultivated organisms. Although P. didemni has not been stably cultivated and comprises a single strain in each sample, a complete set of metabolic genes indicates that the bacteria are likely capable of reproducing outside the host. The sequences reveal notable peculiarities of the photosynthetic apparatus and explain the basis of nutrient exchange underlying the symbiosis. P. didemni likely profoundly influences the lipid composition of the animals by synthesizing sterols and an unusual lipid with biofuel potential. In addition, L. patella also harbors a great variety of other bacterial groups that contribute nutritional and secondary metabolic products to the symbiosis. These bacteria possess an enormous genetic potential to synthesize new secondary metabolites. For example, an antitumor candidate molecule, patellazole, is not encoded in the genome of Prochloron and was linked to other bacteria from the microbiome. This study unveils the complex L. patella microbiome and its impact on primary and secondary metabolism, revealing a remarkable versatility in creating and exchanging small molecules

The Role of Genomics in the Identification, Prediction, and Prevention of Biological Threats

In all likelihood, it is only a matter of time before our public health system will face a major biological threat, whether intentionally dispersed or originating from a known or newly emerging infectious disease. It is necessary not only to increase our reactive “biodefense,” but also to be proactive and increase our preparedness. To achieve this goal, it is essential that the scientific and public health communities fully embrace the genomic revolution, and that novel bioinformatic and computing tools necessary to make great strides in our understanding of these novel and emerging threats be developed. Genomics has graduated from a specialized field of science to a research tool that soon will be routine in research laboratories and clinical settings. Because the technology is becoming more affordable, genomics can and should be used proactively to build our preparedness and responsiveness to biological threats. All pieces, including major continued funding, advances in next-generation sequencing technologies, bioinformatics infrastructures, and open access to data and metadata, are being set in place for genomics to play a central role in our public health system

Assemblathon 2: evaluating de novo methods of genome assembly in three vertebrate species

Background: The process of generating raw genome sequence data continues to become cheaper, faster, and more accurate. However, assembly of such data into high-quality, finished genome sequences remains challenging. Many genome assembly tools are available, but they differ greatly in terms of their performance (speed, scalability, hardware requirements, acceptance of newer read technologies) and in their final output (composition of assembled sequence). More importantly, it remains largely unclear how to best assess the quality of assembled genome sequences. The Assemblathon competitions are intended to assess current state-of-the-art methods in genome assembly. Results: In Assemblathon 2, we provided a variety of sequence data to be assembled for three vertebrate species (a bird, a fish, and snake). This resulted in a total of 43 submitted assemblies from 21 participating teams. We evaluated these assemblies using a combination of optical map data, Fosmid sequences, and several statistical methods. From over 100 different metrics, we chose ten key measures by which to assess the overall quality of the assemblies. Conclusions: Many current genome assemblers produced useful assemblies, containing a significant representation of their genes and overall genome structure. However, the high degree of variability between the entries suggests that there is still much room for improvement in the field of genome assembly and that approaches which work well in assembling the genome of one species may not necessarily work well for another

Diagnosis and treatment of urticaria and angioedema: a worldwide perspective

Urticaria and angioedema are common clinical conditions representing a major concern for physicians and patients alike. The World Allergy Organization (WAO), recognizing the importance of these diseases, has contributed to previous guidelines for the diagnosis and management of urticaria. The Scientific and Clinical Issues Council of WAO proposed the development of this global Position Paper to further enhance the clinical management of these disorders through the participation of renowned experts from all WAO regions of the world. Sections on definition and classification, prevalence, etiology and pathogenesis, diagnosis, treatment, and prognosis are based on the best scientific evidence presently available. Additional sections devoted to urticaria and angioedema in children and pregnant women, quality of life and patient-reported outcomes, and physical urticarias have been incorporated into this document. It is expected that this article will supplement recent international guidelines with the contribution of an expert panel designated by the WAO, increasing awareness of the importance of urticaria and angioedema in medical practice and will become a useful source of information for optimum patient management worldwide

Primary intrinsic chiasmal germinoma

Intracranial germinomas are typically present in the suprasellar or pineal location, and their origin within the optic nerve or chiasm is extremely rare. We report a 25-year-old woman with an exophytic primary optic chiasm germinoma who underwent partial resection followed by radiation and had no detectable tumor on magnetic resonance imaging at 1-year follow-up

Integrated Microbial Survey Analysis of Prokaryotic Communities for the PhyloChip Microarray ▿ †

PhyloTrac is an integrated desktop application for analysis of PhyloChip microarray data. PhyloTrac combined with PhyloChip provides turnkey and comprehensive identification and analysis of bacterial and archaeal communities in complex environmental samples. PhyloTrac is free for noncommercial organizations and is available for all major operating systems at http://www.phylotrac.org/

Encapsidation of RNA-Polyelectrolyte Complexes with Amphiphilic Block Copolymers: Toward a New Self-Assembly Route

Amphiphilic block copolymers are molecules composed of hydrophilic and hydrophobic segments having the capacity to spontaneously self-assemble into a variety of supramolecular structures like micelles and vesicles. Here, we propose an original way to self-assemble amphiphilic block copolymers into a supported bilayer membrane for defined coating of nanoparticles. The heart of the method rests on a change of the amphiphilicity of the copolymer that can be turned off and on by varying the polarity of the solvent. In this condition, the assembly process can take advantage of specific molecular interactions in both organic solvent and water. While the concept potentially could be applied to any type of charged substrates, we focus our interest on the design of a new type of polymer assembly mimicking the virus morphology. A capsid-like shell of glycoprotein-mimic amphiphilic block copolymer was self-assembled around a positively charged complex of siRNA and polyethyleneimine. The process requires two steps. Block copolymers first interact with the complexes dispersed in DMSO through electrostatic interactions. Next, the increase of the water content in the medium triggers the hydrophobic effect and the concomitant self-assembly of free block copolymer molecules into a bilayer membrane at the complex surface. The higher gene silencing activity of the copolymer-modified complexes over the complexes alone shows the potential of this new type of nanoconstructs for biological applications, especially for the delivery of therapeutic biomolecules

Efficacy and safety of the new TightRail™ mechanical sheath for transvenous lead extraction: Results of a French multicenter study

Abstract Introduction The aim of this study was to assess the safety and efficacy of the TightRail™ sheath for pacemaker/defibrillator transvenous lead extraction (TLE). Methods Multicenter observational study including patients who underwent a TLE with the TightRail™ sheath in five French university hospitals from September 2014 to January 2020. Results Two hundred and twenty‐five patients (76% males, 71 ± 12 years) underwent a TLE procedure with the TightRail™. A total of 438 leads were extracted using the TightRail™, and the mean age of the extracted leads was 128 ± 85 months; of these, 344 (79%) were pacing leads and 94 (21%) were implantable cardioverter defibrillator leads. The overall clinical success of the extraction procedures was 93%. Overall, 410 of the 438 leads (95%) were extracted (complete or incomplete removal). After multilevel mixed‐effects logistic regression model, we found that lead age (odds ratio [OR], 95% confidence interval [CI] for a 1 year increase: 1.11 [1.07–1.15], p < .001) and number of leads extracted (OR, 95% CI: 2.09 [1.50–2.96], p < .001) were the two independent factors associated with complete lead removal failure. Finally, there were 7 (3%) cases of major complications but no per‐procedural death. Conclusion This is the first large‐scale survey assessing the efficacy and safety profile of the Tightrail™ mechanical sheath. The clinical success rate was 93%, and the lead removal failure was dependent on the age and number of leads. We show a satisfactory safety profile in this cohort of patients from primarily low‐volume centers with older leads