Nonatherosclerotic Abdominal Vasculopathies.

BACKGROUND: Nonatherosclerotic abdominal arterial vasculopathies (NAVs), including mesenteric or renal artery dissection, aneurysm, stenosis, and vasculitis, are rare but have great clinical significance. Patients may present emergently with life-threatening complications such as arterial rupture and hemorrhagic shock. Herein, we present our center's experience with NAVs and provide extensive literature review to close the gap in the scarce, related literature. METHODS: From a single-center retrospective data analysis, we identified and characterized subjects (aged 18-60 years) who presented with NAV between January 2000 and December 2015. Of the 1416 charts reviewed, 118 met inclusion criteria. RESULTS: The average age of patients with NAV was 47.0 ± 9.9 years, mostly affecting women (64%). Primary diagnoses included fibromuscular dysplasia (FMD) (25.4%), isolated aneurysms (24.6%), and median arcuate ligament syndrome (MALS) (15.3%). Less common diagnoses were localized vasculitis of the gastrointestinal tract (LVGT) (7.6%), isolated dissection (5.1%), microscopic polyangiitis and granulomatosis with polyangiitis (5.1%), trauma (4.2%), segmental arterial mediolysis (4.2%), Ehlers-Danlos syndrome (2.5%), Takayasu's arteritis (2.5%), polyarteritis nodosa (1.7%), idiopathic abdominal aortitis (0.8%), and Loeys-Dietz syndrome (0.8%). Females constituted 90% of patients with FMD, 77.8% with MALS, 77.8% with isolated aneurysms, 66.7% with Takayasu arteritis, and 55.6% with LVGT. Prevalent comorbidities included tobacco use (43.6%) and hypertension (52.1%). Coil embolization was used in 14.4%, anticoagulation in 11.9%, angioplasty/stenting in 11.9%, open resection/surgical revascularization in 10.2%, and prednisone in 10.2% of the cases. Conservative management was pursued in 33.1% of the patients. A high degree of symptom relief was shown in 91.7%. CONCLUSIONS: NAV are rare and can be caused by different etiologies that primarily affect females. Hypertension and tobacco use were prevalent. Various imaging strategies revealed aneurysms, stenosis, dissection, and/or thrombosis affecting renal and celiac arteries. Most patients improved with conservative, medical, endovascular, or surgical approach. More research is needed to standardize management approach to patients with NAV.

Extensive Cerebrovascular and Visceral Artery Dissection and Pseudoaneurysm with Underlying Segmental Arterial Mediolysis.

Segmental arterial mediolysis (SAM) is a nonatherosclerotic, nonhereditary vasculopathy that most commonly involves abdominal aortic branches and predominantly affects middle-age and elderly populations. Lysis of the outer arterial media results in separation of the media from the adventitia leading to dissecting aneurysms and/or pseudoaneurysms. We report a unique case of a 47-year-old man who presented with bilateral internal carotid artery dissection followed by dissections and aneurysms involving multiple visceral arteries. This case highlights the dramatic manifestation of SAM and discusses the complexity of decision-making related to this disease including differential diagnoses and management.

Diversity and conservation of the genome architecture of phages infecting the Alphaproteobacteria.

IMPORTANCE: This study reports the results of the largest analysis of genome sequences from phages that infect the Alphaproteobacteria class of bacterial hosts. We analyzed over 100 whole genome sequences of phages to construct dotplots, categorize them into genetically distinct clusters, generate a bootstrapped phylogenetic tree, compute protein orthologs, and predict packaging strategies. We determined that the phage sequences primarily cluster by the bacterial host family, phage morphotype, and genome size. We expect that the findings reported in this seminal study will facilitate future analyses that will improve our knowledge of the phages that infect these hosts.

Genome Sequences of Nine Erwinia amylovora Bacteriophages.

Erwinia amylovora is a plant pathogen belonging to the Enterobacteriaceae family, a family containing many plant and animal pathogens. Herein, we announce nine genome sequences of E. amylovora bacteriophages isolated from infected apple trees along the Wasatch Front in Utah.

Genome Sequences of 19 Novel Erwinia amylovora Bacteriophages.

Erwinia amylovora is the causal agent of fire blight, a devastating disease affecting some plants of the Rosaceae family. We isolated bacteriophages from samples collected from infected apple and pear trees along the Wasatch Front in Utah. We announce 19 high-quality complete genome sequences of E. amylovora bacteriophages.

Characterization of Five Novel Brevibacillus Bacteriophages and Genomic Comparison of Brevibacillus Phages.

Brevibacillus laterosporus is a spore-forming bacterium that causes a secondary infection in beehives following European Foulbrood disease. To better understand the contributions of Brevibacillus bacteriophages to the evolution of their hosts, five novel phages (Jenst, Osiris, Powder, SecTim467, and Sundance) were isolated and characterized. When compared with the five Brevibacillus phages currently in NCBI, these phages were assigned to clusters based on whole genome and proteome synteny. Powder and Osiris, both myoviruses, were assigned to the previously described Jimmer-like cluster. SecTim467 and Jenst, both siphoviruses, formed a novel phage cluster. Sundance, a siphovirus, was assigned as a singleton phage along with the previously isolated singleton, Emery. In addition to characterizing the basic relationships between these phages, several genomic features were observed. A motif repeated throughout phages Jenst and SecTim467 was frequently upstream of genes predicted to function in DNA replication, nucleotide metabolism, and transcription, suggesting transcriptional co-regulation. In addition, paralogous gene pairs that encode a putative transcriptional regulator were identified in four Brevibacillus phages. These paralogs likely evolved to bind different DNA sequences due to variation at amino acid residues predicted to bind specific nucleotides. Finally, a putative transposable element was identified in SecTim467 and Sundance that carries genes homologous to those found in Brevibacillus chromosomes. Remnants of this transposable element were also identified in phage Jenst. These discoveries provide a greater understanding of the diversity of phages, their behavior, and their evolutionary relationships to one another and to their host. In addition, they provide a foundation with which further Brevibacillus phages can be compared.