Polymer dynamics of Alp7A reveals how two critical concentrations govern assembly of dynamically unstable actin-like proteins.

Dynamically unstable polymers capture and move cellular cargos in bacteria and eukaryotes, but regulation of their assembly remains poorly understood. Here we describe polymerization of Alp7A, a bacterial actin-like protein (ALP) that distributes copies of plasmid pLS20 among daughter cells in . Purified ATP-Alp7A forms dynamically unstable polymers with a high critical concentration for net assembly (cc = 10.

Catabolism of germinant amino acids is required to prevent premature spore germination in .

Unlabelled: Spores of germinate in response to specific germinant molecules that are recognized by receptors in the spore envelope. Germinants signal to the dormant spore that the environment can support vegetative growth, so many germinants, such as alanine and valine, are also essential metabolites. As such, they are also required to build the spore.

Highly time-resolved 4D MR angiography using golden-angle radial sparse parallel (GRASP) MRI.

Current dynamic MRA techniques are limited by temporal resolution and signal-to-noise penalties. GRASP, a fast and flexible MRI technique combining compressed-sensing, parallel imaging, and golden-angle radial sampling, acquires volumetric data continuously and can be reconstructed post hoc for user-defined applications. We describe a custom pipeline to retrospectively reconstruct ultrahigh temporal resolution, dynamic MRA from GRASP imaging obtained in the course of routine practice.

A Worm's Tale or Why to Avoid the Raccoon Latrine: A Case of Meningoencephalitis.

The raccoon roundworm () may infect humans to cause severe or fatal meningoencephalitis, as well as ocular and visceral larva migrans. Young children are at greater risk for cerebral larva migrans with severe meningoencephalitis, and early empiric therapy may improve outcomes. Familiarity with characteristic brain imaging findings may prompt earlier diagnosis, particularly in the setting of CSF eosinophilia.

Development and validation of a simple and practical method for differentiating MS from other neuroinflammatory disorders based on lesion distribution on brain MRI.

There is an unmet need to develop practical methods for differentiating multiple sclerosis (MS) from other neuroinflammatory disorders using standard brain MRI. To develop a practical approach for differentiating MS from neuromyelitis optica spectrum disorder (NMOSD) and MOG antibody-associated disorder (MOGAD) with brain MRI, we first identified lesion locations in the brain that are suggestive of MS-associated demyelination ("MS Lesion Checklist") and compared frequencies of brain lesions in the "MS Lesion Checklist" locations in a development sample of patients (n = 82) with clinically definite MS, NMOSD, and MOGAD. Patients with MS were more likely than patients with non-MS to have lesions in 3 locations only: anterior temporal horn (p < 0.

Isolation and characterization of Streptomyces bacteriophages and Streptomyces strains encoding biosynthetic arsenals.

The threat to public health posed by drug-resistant bacteria is rapidly increasing, as some of healthcare's most potent antibiotics are becoming obsolete. Approximately two-thirds of the world's antibiotics are derived from natural products produced by Streptomyces encoded biosynthetic gene clusters. Thus, to identify novel gene clusters, we sequenced the genomes of four bioactive Streptomyces strains isolated from the soil in San Diego County and used Bacterial Cytological Profiling adapted for agar plate culturing in order to examine the mechanisms of bacterial inhibition exhibited by these strains.

Vessel wall imaging with advanced flow suppression in the characterization of intracranial aneurysms following flow diversion with Pipeline embolization device.

Background: High-resolution vessel wall MRI (VWI) is increasingly used to characterize intramural disorders of the intracranial vasculature unseen by conventional arteriography.

Objective: To evaluate the use of VWI for surveillance of flow diverter (FD) treated aneurysms.

Materials And Methods: Retrospective study of 28 aneurysms (in 21 patients) treated with a FD (mean 57 years; 14 female).

Bacterial Cytological Profiling Identifies Rhodanine-Containing PAINS Analogs as Specific Inhibitors of Thymidylate Kinase .

In this study, we sought to determine whether an assay for studying antibiotic mechanisms of action could provide insight into the activity of compounds that may inhibit multiple targets. Thus, we conducted an activity screen of 31 structural analogs of rhodanine-containing pan-assay interference compounds (PAINS). We identified nine active molecules against Escherichia coli and classified them according to their mechanisms of action.

Milestones in sporulation research.

Endospore formation has been a rich field of research for more than a century, and has benefited from the powerful genetic tools available in . In this review, we highlight foundational discoveries that shaped the sporulation field, from its origins to the present day, tracing a chronology that spans more than one hundred eighty years. We detail how cell-specific gene expression has been harnessed to investigate the existence and function of intercellular proteinaceous channels in sporulating cells, and we illustrate the rapid progress in our understanding of the cell biology of sporulation in recent years using the process of chromosome translocation as a storyline.

Atherosclerotic cardiovascular disease in inflammatory bowel disease: The role of chronic inflammation.

Inflammatory bowel disease (IBD) causes systemic vascular inflammation. The increased risk of venous as well as arterial thromboembolic phenomena in IBD is well established. More recently, a relationship between IBD and atherosclerotic cardiovascular disease (ASCVD) has been postulated.

Brain Imaging Use and Findings in COVID-19: A Single Academic Center Experience in the Epicenter of Disease in the United States.

Coronavirus disease 2019 (COVID-19) is a serious public health crisis and can have neurologic manifestations. This is a retrospective observational case series performed March 1-31, 2020, at New York University Langone Medical Center campuses. Clinical and imaging data were extracted, reviewed, and analyzed.

COVID-19-associated Diffuse Leukoencephalopathy and Microhemorrhages.

Diffuse leukoencephalopathy and juxtacortical and/or callosal microhemorrhages were brain imaging features in critically ill patients with coronavirus disease 2019. Coronavirus disease 2019 (COVID-19) has been reported in association with a variety of brain imaging findings such as ischemic infarct, hemorrhage, and acute hemorrhagic necrotizing encephalopathy. Herein, the authors report brain imaging features in 11 critically ill patients with COVID-19 with persistently diminished mental status who underwent MRI between April 5 and April 25, 2020.

Carotid intimal sarcoma causing stroke and intracranial metastasis via tumor embolization.

Objective: To present the clinical, radiologic, and pathologic findings of a patient with carotid intimal sarcoma.

Methods: Detailed medical interview, neurologic examination, and diagnostic evaluation including CT angiography head and neck, MRI brain and neck, digital subtraction angiography, and biopsy of the mass were performed.

Results: We report a patient who presented with symptoms of multifocal, bilateral strokes over weeks caused by an enlarging tumor thrombus associated with an intimal sarcoma of the carotid artery.

Extension of the Thoracic Spine Sign: A New Sonographic Marker of Pleural Effusion.

Objectives: Dyspnea is a common emergency department (ED) condition, which may be caused by pleural effusion and other thoracic diseases. We present data on a new sonographic marker, the extension of the thoracic spine sign, for diagnosis of pleural effusion.

Methods: In this prospective study, we enrolled a convenience sample of undifferentiated patients who underwent computed tomography (CT) of the abdomen or chest, which was performed as part of their emergency department evaluations.

Phase II study of everolimus in children and adults with neurofibromatosis type 2 and progressive vestibular schwannomas.

Background: Activation of the mammalian target of rapamycin (mTOR) signaling pathway is thought to be a key driver of tumor growth in Merlin (NF2)-deficient tumors. Everolimus is an oral inhibitor of mTOR complex 1 (mTORC1) with antitumor activity in a variety of cancers.

Methods: We conducted a single-institution, prospective, 2-stage, open-label phase II study to estimate the response rate to everolimus in neurofibromatosis type 2 (NF2) patients with progressive vestibular schwannoma (VS).

Bacillus subtilis strain engineered for treatment of soil-transmitted helminth diseases.

Soil-transmitted helminths (hookworms, whipworms, and large roundworms) are agents of intestinal roundworm diseases of poverty that infect upwards of 2 billion people worldwide. A great challenge in treating these diseases is the development of anthelmintic therapeutics that are inexpensive, can be produced in great quantity, and are capable of delivery under varied and adverse environmental conditions. A potential solution to this challenge is the use of live bacteria that are acceptable for human consumption, e.

Perforated Meckel's diverticulum presenting as a hematocele on scrotal sonography.

Hemorrhage from ectopic gastric mucosa is the most common presenting symptom of Meckel's diverticulum. Diverticular perforation, although rare, is a potentially life-threatening complication. Various imaging modalities can aid in the preoperative detection of Meckel's diverticulum.

Alp7R regulates expression of the actin-like protein Alp7A in Bacillus subtilis.

Alp7A is a bacterial actin from Bacillus subtilis plasmid pLS20 that functions in plasmid segregation. Alp7A's function requires that it assemble into filaments that treadmill and exhibit dynamic instability. These dynamic properties require the two other components of the alp7A operon, the downstream alp7R gene and the upstream alp7C sequence, as does the ability of Alp7A to form filaments at its physiological concentration in the cell.

MRI of placenta accreta: a new imaging perspective.

Objective: The goal of this study was to identify new MR criteria and review established MR criteria for the diagnosis of placenta accreta. MR images of all patients presenting to our department for evaluation of placenta accreta over the previous 5 years were reviewed and findings were correlated with surgical pathology.

Conclusion: We found the most sensitive MR criteria for the diagnosis of invasive placentation to be abnormal placental vascularity in addition to the previously described intraplacental T2 dark bands.

Autofluorescence imaging of potentially malignant mucosa lesions.

Objective And Study Design: Several noninvasive adjunctive methods have been proposed for identification of potentially malignant mucosa lesions. The VELscope is an optical device for detecting spatial changes in mucosa autofluorescence caused by premalignant lesions in conjunction with an intraoral exam. The aim of our prospective study was to correlate loss of autofluorescence from undiagnosed mucosa lesions with histology.

Phylogenetic analysis identifies many uncharacterized actin-like proteins (Alps) in bacteria: regulated polymerization, dynamic instability and treadmilling in Alp7A.

Actin, one of the most abundant proteins in the eukaryotic cell, also has an abundance of relatives in the eukaryotic proteome. To date though, only five families of actins have been characterized in bacteria. We have conducted a phylogenetic search and uncovered more than 35 highly divergent families of actin-like proteins (Alps) in bacteria.