Local Expansion of a Panmictic Lineage of Water Bloom-Forming Cyanobacterium Microcystis aeruginosa

In previous studies, we have demonstrated that the population structure of the bloom-forming cyanobacterium Microcystis aeruginosa is clonal. Expanded multilocus sequence typing analysis of M. aeruginosa using 412 isolates identified five intraspecific lineages suggested to be panmictic while maintaining overall clonal structure probably due to a reduced recombination rate between lineages. Interestingly, since 2005 most strains belonging to one of these panmictic clusters (group G) have been found in a particular locality (Lake Kasumigaura Basin) in Japan. In this locality, multiple, similar but distinct genotypes of this lineage predominated in the bloom, a pattern that is unprecedented for M. aeruginosa. The population structure underlying blooms associated with this lineage is comparable to epidemics of pathogens. Our results may reveal an expansion of the possible adaptive lineage in a localized aquatic environment, providing us with a unique opportunity to investigate its ecological and biogeographical consequences

Conditions for the Evolution of Gene Clusters in Bacterial Genomes

Genes encoding proteins in a common pathway are often found near each other along bacterial chromosomes. Several explanations have been proposed to account for the evolution of these structures. For instance, natural selection may directly favour gene clusters through a variety of mechanisms, such as increased efficiency of coregulation. An alternative and controversial hypothesis is the selfish operon model, which asserts that clustered arrangements of genes are more easily transferred to other species, thus improving the prospects for survival of the cluster. According to another hypothesis (the persistence model), genes that are in close proximity are less likely to be disrupted by deletions. Here we develop computational models to study the conditions under which gene clusters can evolve and persist. First, we examine the selfish operon model by re-implementing the simulation and running it under a wide range of conditions. Second, we introduce and study a Moran process in which there is natural selection for gene clustering and rearrangement occurs by genome inversion events. Finally, we develop and study a model that includes selection and inversion, which tracks the occurrence and fixation of rearrangements. Surprisingly, gene clusters fail to evolve under a wide range of conditions. Factors that promote the evolution of gene clusters include a low number of genes in the pathway, a high population size, and in the case of the selfish operon model, a high horizontal transfer rate. The computational analysis here has shown that the evolution of gene clusters can occur under both direct and indirect selection as long as certain conditions hold. Under these conditions the selfish operon model is still viable as an explanation for the evolution of gene clusters

Arrhythmia and death following percutaneous revascularization in ischemic left ventricular dysfunction: Prespecified analyses from the REVIVED-BCIS2 trial

BACKGROUND: Ventricular arrhythmia is an important cause of mortality in patients with ischemic left ventricular dysfunction. Revascularization with coronary artery bypass graft or percutaneous coronary intervention is often recommended for these patients before implantation of a cardiac defibrillator because it is assumed that this may reduce the incidence of fatal and potentially fatal ventricular arrhythmias, although this premise has not been evaluated in a randomized trial to date. METHODS: Patients with severe left ventricular dysfunction, extensive coronary disease, and viable myocardium were randomly assigned to receive either percutaneous coronary intervention (PCI) plus optimal medical and device therapy (OMT) or OMT alone. The composite primary outcome was all-cause death or aborted sudden death (defined as an appropriate implantable cardioverter defibrillator therapy or a resuscitated cardiac arrest) at a minimum of 24 months, analyzed as time to first event on an intention-to-treat basis. Secondary outcomes included cardiovascular death or aborted sudden death, appropriate implantable cardioverter defibrillator (ICD) therapy or sustained ventricular arrhythmia, and number of appropriate ICD therapies. RESULTS: Between August 28, 2013, and March 19, 2020, 700 patients were enrolled across 40 centers in the United Kingdom. A total of 347 patients were assigned to the PCI+OMT group and 353 to the OMT alone group. The mean age of participants was 69 years; 88% were male; 56% had hypertension; 41% had diabetes; and 53% had a clinical history of myocardial infarction. The median left ventricular ejection fraction was 28%; 53.1% had an implantable defibrillator inserted before randomization or during follow-up. All-cause death or aborted sudden death occurred in 144 patients (41.6%) in the PCI group and 142 patients (40.2%) in the OMT group (hazard ratio, 1.03 [95% CI, 0.82–1.30]; P =0.80). There was no between-group difference in the occurrence of any of the secondary outcomes. CONCLUSIONS: PCI was not associated with a reduction in all-cause mortality or aborted sudden death. In patients with ischemic cardiomyopathy, PCI is not beneficial solely for the purpose of reducing potentially fatal ventricular arrhythmias. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01920048

Abrahams visual guide to clinical anatomy [electronic resource]

This outstanding DVD features over 1,000 clinical photos presented with short clinical vignettes to help you recognize over 300 common conditions. Taken from the outstanding McMinn's "Clinical Atlas of Human Anatomy 6th Edition", this DVD offers you a wealth of images not easily found in one place and accompanied by numerous questions to help test your knowledge. Whether you are preparing for exams or want to develop and improve your diagnostic skills this DVD will provide you with an easy-to-use visual guide

Clinical atlas of human anatomy

x, 387 hlm.: 26 c

Incidence and Potential Significance of Internal Mammary Lymphadenopathy on Computed Tomography in Patients with a Diagnosis of Primary Breast Cancer

Introduction The importance of internal mammary nodes (IMNs) in the staging and treatment of breast cancer patients is controversial. Methods A retrospective cohort of patients diagnosed with primary breast cancer over a 4-year period (January 2009 to December 2012) was assessed. The number and size of any IMNs visible on spiral computed tomography (CT) were recorded. Results A total of 830 patients were diagnosed with primary breast cancer within the identified time frame, of which 150 patients met the inclusion criteria. Of these 42% (63) had IMNs present, although the majority were small (<5 mm). However, 16% (25) had larger nodes, greater than 5 mm in short axis, present on CT. Significantly more patients with the presence of large (>5 mm) IMNs had more advanced disease with CT evidence of other distant spread. Conclusion We have demonstrated that IMNs are present in a substantial number of our primary breast cancer patients. We suggest that further histological research is required to establish reliable CT size criterion for pathological IMNs. In addition, routine imaging of the IM chain, as well as axilla, should be considered in the staging of breast cancer

McMinn's clinical atlas of human anatomy

This title helps you map out all of the key structures of the human body with examples of real human dissections...and easily place them in a clinical context! This popular atlas incorporates an unrivalled collection of cadaveric, osteological, and clinical images with surface anatomy models, interpretive drawings, orientational diagrams, and diagnostic images emphasising a well-rounded visual perspective of a real human body as seen by modern doctors

Imaging atlas of human anatomy

"Imaging Atlas of Human Anatomy, 4th Edition" provides a solid foundation for understanding human anatomy. Jamie Weir, Peter Abrahams, Jonathan D. Spratt, and Lonie Salkowski offer a complete and 3-dimensional view of the structures and relationships within the body through a variety of imaging modalities. Over 60 per cent new images - showing cross-sectional views in CT and MRI, nuclear medicine imaging, and more - along with revised legends and labels ensure that you have the best and most up-to-date visual resource. In addition, you'll get free online access to 10 pathology tutorials linking to additional images for even more complete coverage than ever before (with the opportunity to upgrade to more online tutorials)