rom Health Tip: What to Expect From a Gynecologist Visit By www.medicinenet.com Published On :: Sat, 9 May 2020 00:00:00 PDT Title: Health Tip: What to Expect From a Gynecologist VisitCategory: Health NewsCreated: 5/3/2019 12:00:00 AMLast Editorial Review: 5/3/2019 12:00:00 AM Full Article
rom AHA News: Firefighter In Need of a New Heart Got By With a Little Help From His Friends By www.medicinenet.com Published On :: Sat, 9 May 2020 00:00:00 PDT Title: AHA News: Firefighter In Need of a New Heart Got By With a Little Help From His FriendsCategory: Health NewsCreated: 4/24/2020 12:00:00 AMLast Editorial Review: 4/27/2020 12:00:00 AM Full Article
rom As Coronavirus Fears Surge, Keep Cleaning Products Away From Children By www.medicinenet.com Published On :: Sat, 9 May 2020 00:00:00 PDT Title: As Coronavirus Fears Surge, Keep Cleaning Products Away From ChildrenCategory: Health NewsCreated: 4/27/2020 12:00:00 AMLast Editorial Review: 4/27/2020 12:00:00 AM Full Article
rom He Recovered From COVID-19. Can His Blood Help Others? By www.medicinenet.com Published On :: Sat, 9 May 2020 00:00:00 PDT Title: He Recovered From COVID-19. Can His Blood Help Others?Category: Health NewsCreated: 4/27/2020 12:00:00 AMLast Editorial Review: 4/27/2020 12:00:00 AM Full Article
rom Coronavirus Vaccine Shows Promise By www.medicinenet.com Published On :: Sat, 9 May 2020 00:00:00 PDT Title: Coronavirus Vaccine Shows PromiseCategory: Health NewsCreated: 4/29/2020 12:00:00 AMLast Editorial Review: 4/29/2020 12:00:00 AM Full Article
rom Costs Would Keep 1 in 7 Americans From Seeking COVID-19 Treatment By www.medicinenet.com Published On :: Sat, 9 May 2020 00:00:00 PDT Title: Costs Would Keep 1 in 7 Americans From Seeking COVID-19 TreatmentCategory: Health NewsCreated: 4/28/2020 12:00:00 AMLast Editorial Review: 4/29/2020 12:00:00 AM Full Article
rom Temporomandibular Joint Syndrome (TMJ) By www.medicinenet.com Published On :: Fri, 27 Mar 2020 00:00:00 PDT Title: Temporomandibular Joint Syndrome (TMJ) Category: Diseases and ConditionsCreated: 3/26/1998 12:00:00 AMLast Editorial Review: 3/27/2020 12:00:00 AM Full Article
rom New Drug Could Help Stop Blindness From Thyroid Eye Disease By www.medicinenet.com Published On :: Thu, 23 Jan 2020 00:00:00 PDT Title: New Drug Could Help Stop Blindness From Thyroid Eye DiseaseCategory: Health NewsCreated: 1/22/2020 12:00:00 AMLast Editorial Review: 1/23/2020 12:00:00 AM Full Article
rom FDA Bans Products That Help Kids Hide Vape Use From Parents By www.medicinenet.com Published On :: Tue, 28 Apr 2020 00:00:00 PDT Title: FDA Bans Products That Help Kids Hide Vape Use From ParentsCategory: Health NewsCreated: 4/27/2020 12:00:00 AMLast Editorial Review: 4/28/2020 12:00:00 AM Full Article
rom Justice Ginsberg Joins Court Call from Hospital By www.webmd.com Published On :: Wed, 06 May 2020 14:36:12 EST Ginsberg joined in from the Maryland hospital where she's being treated for an infection caused by a gall stone. Full Article
rom Supreme Court Justice Ginsburg Home From Hospital By www.webmd.com Published On :: Thu, 07 May 2020 11:29:44 EST Ginsburg had gone to the hospital for outpatient tests that revealed an infection caused by a gall stone. Full Article
rom Iliotibial (IT) Band Syndrome By www.medicinenet.com Published On :: Tue, 10 Mar 2020 00:00:00 PDT Title: Iliotibial (IT) Band SyndromeCategory: Diseases and ConditionsCreated: 4/18/2011 12:00:00 AMLast Editorial Review: 3/10/2020 12:00:00 AM Full Article
rom How Long Does It Take to Recover from Laparoscopic Inguinal Hernia Surgery? By www.medicinenet.com Published On :: Fri, 1 May 2020 00:00:00 PDT Title: How Long Does It Take to Recover from Laparoscopic Inguinal Hernia Surgery?Category: Procedures and TestsCreated: 5/1/2020 12:00:00 AMLast Editorial Review: 5/1/2020 12:00:00 AM Full Article
rom Certain Gene Might Help Shield At-Risk People From Alzheimer's By www.medicinenet.com Published On :: Tue, 14 Apr 2020 00:00:00 PDT Title: Certain Gene Might Help Shield At-Risk People From Alzheimer'sCategory: Health NewsCreated: 4/13/2020 12:00:00 AMLast Editorial Review: 4/14/2020 12:00:00 AM Full Article
rom Hantavirus Pulmonary Syndrome (HPS) By www.medicinenet.com Published On :: Tue, 24 Mar 2020 00:00:00 PDT Title: Hantavirus Pulmonary Syndrome (HPS)Category: Diseases and ConditionsCreated: 4/21/2010 12:00:00 AMLast Editorial Review: 3/24/2020 12:00:00 AM Full Article
rom New Polio Vaccine Promising in Early Test By www.medicinenet.com Published On :: Mon, 27 Apr 2020 00:00:00 PDT Title: New Polio Vaccine Promising in Early TestCategory: Health NewsCreated: 4/24/2020 12:00:00 AMLast Editorial Review: 4/27/2020 12:00:00 AM Full Article
rom Vitamin D Might Aid Seniors' Recovery From Hip Fracture: Study By www.medicinenet.com Published On :: Fri, 3 Apr 2020 00:00:00 PDT Title: Vitamin D Might Aid Seniors' Recovery From Hip Fracture: StudyCategory: Health NewsCreated: 4/2/2020 12:00:00 AMLast Editorial Review: 4/3/2020 12:00:00 AM Full Article
rom Experimental Drug Shows Promise for Schizophrenia By www.medicinenet.com Published On :: Fri, 17 Apr 2020 00:00:00 PDT Title: Experimental Drug Shows Promise for SchizophreniaCategory: Health NewsCreated: 4/16/2020 12:00:00 AMLast Editorial Review: 4/17/2020 12:00:00 AM Full Article
rom U.S. Deaths From High Blood Pressure Soar, Especially in the South: Study By www.medicinenet.com Published On :: Tue, 24 Mar 2020 00:00:00 PDT Title: U.S. Deaths From High Blood Pressure Soar, Especially in the South: StudyCategory: Health NewsCreated: 3/23/2020 12:00:00 AMLast Editorial Review: 3/24/2020 12:00:00 AM Full Article
rom Veltassa (patiromer) By www.medicinenet.com Published On :: Wed, 18 Mar 2020 00:00:00 PDT Title: Veltassa (patiromer)Category: MedicationsCreated: 3/18/2020 12:00:00 AMLast Editorial Review: 3/18/2020 12:00:00 AM Full Article
rom Promacta (eltrombopag) By www.medicinenet.com Published On :: Wed, 22 Apr 2020 00:00:00 PDT Title: Promacta (eltrombopag)Category: MedicationsCreated: 4/22/2020 12:00:00 AMLast Editorial Review: 4/22/2020 12:00:00 AM Full Article
rom azithromycin (Zithromax): Potential COVID-19 Combo Drug By www.medicinenet.com Published On :: Mon, 30 Mar 2020 00:00:00 PDT Title: azithromycin (Zithromax): Potential COVID-19 Combo DrugCategory: MedicationsCreated: 12/31/1997 12:00:00 AMLast Editorial Review: 3/30/2020 12:00:00 AM Full Article
rom Replace That Old Carpet to Shield Your Kids From Toxins By www.medicinenet.com Published On :: Thu, 30 Apr 2020 00:00:00 PDT Title: Replace That Old Carpet to Shield Your Kids From ToxinsCategory: Health NewsCreated: 4/29/2020 12:00:00 AMLast Editorial Review: 4/30/2020 12:00:00 AM Full Article
rom Magnetic Brain 'Zap' Shows Promise Against Severe Depression By www.medicinenet.com Published On :: Wed, 8 Apr 2020 00:00:00 PDT Title: Magnetic Brain 'Zap' Shows Promise Against Severe DepressionCategory: Health NewsCreated: 4/7/2020 12:00:00 AMLast Editorial Review: 4/8/2020 12:00:00 AM Full Article
rom Unplugging From Social Media on Vacation? It's Tough at First By www.medicinenet.com Published On :: Wed, 14 Aug 2019 00:00:00 PDT Title: Unplugging From Social Media on Vacation? It's Tough at FirstCategory: Health NewsCreated: 8/14/2019 12:00:00 AMLast Editorial Review: 8/14/2019 12:00:00 AM Full Article
rom Silence Your Snore, Save Your Romance By www.medicinenet.com Published On :: Mon, 10 Feb 2020 00:00:00 PDT Title: Silence Your Snore, Save Your RomanceCategory: Health NewsCreated: 2/9/2020 12:00:00 AMLast Editorial Review: 2/10/2020 12:00:00 AM Full Article
rom Restful Romance: Smelling Your Lover's Shirt Can Help You Sleep By www.medicinenet.com Published On :: Fri, 14 Feb 2020 00:00:00 PDT Title: Restful Romance: Smelling Your Lover's Shirt Can Help You SleepCategory: Health NewsCreated: 2/14/2020 12:00:00 AMLast Editorial Review: 2/14/2020 12:00:00 AM Full Article
rom Anti-KIT DNA Aptamer for Targeted Labeling of Gastrointestinal Stromal Tumor By mct.aacrjournals.org Published On :: 2020-05-04T05:39:42-07:00 Gastrointestinal stromal tumor (GIST), the most common sarcoma, is characterized by KIT protein overexpression, and tumors are frequently driven by oncogenic KIT mutations. Targeted inhibition of KIT revolutionized GIST therapy and ushered in the era of precision medicine for the treatment of solid malignancies. Here, we present the first use of a KIT-specific DNA aptamer for targeted labeling of GIST. We found that an anti-KIT DNA aptamer bound cells in a KIT-dependent manner and was highly specific for GIST cell labeling in vitro. Functionally, the KIT aptamer bound extracellular KIT in a manner similar to KIT mAb staining, and was trafficked intracellularly in vitro. The KIT aptamer bound dissociated primary human GIST cells in a mutation agnostic manner such that tumors with KIT and PDGFRA mutations were labeled. In addition, the KIT aptamer specifically labeled intact human GIST tissue ex vivo, as well as peritoneal xenografts in mice with high sensitivity. These results represent the first use of an aptamer-based method for targeted detection of GIST in vitro and in vivo. Full Article
rom Selected Articles from This Issue By mct.aacrjournals.org Published On :: 2020-05-04T05:39:42-07:00 Full Article
rom Two previously unrecorded xiphosurid trace fossils, Selenichnites rossendalensis and Crescentichnus tesiltus, from the Middle Jurassic of Yorkshire, UK By pygs.lyellcollection.org Published On :: 2019-11-22T06:43:26-08:00 The invertebrate trace fossils Selenichnites rossendalensis and Crescentichnus tesiltus are recorded and described from the Middle Jurassic Gristhorpe Member of the Cloughton Formation of the Cleveland Basin. This is the first record of these ichnospecies from the basin and now completes the occurrence of these and other traces assumed to have been made by limulids from all three non-marine formations of the Ravenscar Group. Full Article
rom Top-Cited Articles from Dental Education Journals, 2009 to 2018: A Bibliometric Analysis By www.jdentaled.org Published On :: 2019-12-01T06:00:18-08:00 The number of citations an article receives is an important indicator to quantify its influence in its field. The aim of this study was to identify and analyze the characteristics of the 50 top-cited articles addressing dental education published in two journals dedicated to dental education (European Journal of Dental Education and Journal of Dental Education). The Web of Science database was searched to retrieve the 50 most-cited articles from the two journals in December 2018. The top-cited articles were analyzed for journal of publication, number of citations, institution and country of origin, year of publication, study type, keywords, theme and subtheme, and international collaborations. The results showed the 50 top-cited articles were cited between 24 and 146 times each. The majority of these top-cited articles (n=34) were published in the Journal of Dental Education. Half (n=25) of the articles were by authors in the U.S. The most common study types were surveys (n=26) and reviews (n=10). The main themes of these top-cited articles were curriculum and learner characteristics. This bibliometric analysis can serve as a reference for recognizing studies with the most impact in the scholarship of dental education. Full Article
rom Obesity-Related Microenvironment Promotes Emergence of Virulent Influenza Virus Strains By mbio.asm.org Published On :: 2020-03-03T01:30:27-08:00 ABSTRACT Obesity is associated with increased disease severity, elevated viral titers in exhaled breath, and significantly prolonged viral shed during influenza A virus infection. Due to the mutable nature of RNA viruses, we questioned whether obesity could also influence influenza virus population diversity. Here, we show that minor variants rapidly emerge in obese mice. The variants exhibit increased viral replication, resulting in enhanced virulence in wild-type mice. The increased diversity of the viral population correlated with decreased type I interferon responses, and treatment of obese mice with recombinant interferon reduced viral diversity, suggesting that the delayed antiviral response exhibited in obesity permits the emergence of a more virulent influenza virus population. This is not unique to obese mice. Obesity-derived normal human bronchial epithelial (NHBE) cells also showed decreased interferon responses and increased viral replication, suggesting that viral diversity also was impacted in this increasing population. IMPORTANCE Currently, 50% of the adult population worldwide is overweight or obese. In these studies, we demonstrate that obesity not only enhances the severity of influenza infection but also impacts viral diversity. The altered microenvironment associated with obesity supports a more diverse viral quasispecies and affords the emergence of potentially pathogenic variants capable of inducing greater disease severity in lean hosts. This is likely due to the impaired interferon response, which is seen in both obese mice and obesity-derived human bronchial epithelial cells, suggesting that obesity, aside from its impact on influenza virus pathogenesis, permits the stochastic accumulation of potentially pathogenic viral variants, raising concerns about its public health impact as the prevalence of obesity continues to rise. Full Article
rom The Multifunctional Long-Distance Movement Protein of Pea Enation Mosaic Virus 2 Protects Viral and Host Transcripts from Nonsense-Mediated Decay By mbio.asm.org Published On :: 2020-03-10T01:30:41-07:00 ABSTRACT The nonsense-mediated decay (NMD) pathway presents a challenge for RNA viruses with termination codons that precede extended 3' untranslated regions (UTRs). The umbravirus Pea enation mosaic virus 2 (PEMV2) is a nonsegmented, positive-sense RNA virus with an unusually long 3' UTR that is susceptible to NMD. To establish a systemic infection, the PEMV2 long-distance movement protein p26 was previously shown to both stabilize viral RNAs and bind them for transport through the plant’s vascular system. The current study demonstrated that p26 protects both viral and nonviral messenger RNAs from NMD. Although p26 localizes to both the cytoplasm and nucleolus, p26 exerts its anti-NMD effects exclusively in the cytoplasm independently of long-distance movement. Using a transcriptome-wide approach in the model plant Nicotiana benthamiana, p26 protected a subset of cellular NMD target transcripts, particularly those containing long, structured, GC-rich 3' UTRs. Furthermore, transcriptome sequencing (RNA-seq) revealed that the NMD pathway is highly dysfunctional during PEMV2 infection, with 1,820 (48%) of NMD targets increasing in abundance. Widespread changes in the host transcriptome are common during plant RNA virus infections, and these results suggest that, in at least some instances, virus-mediated NMD inhibition may be a major contributing factor. IMPORTANCE Nonsense-mediated decay (NMD) represents an RNA regulatory pathway that degrades both natural and faulty messenger RNAs with long 3' untranslated regions. NMD targets diverse families of RNA viruses, requiring that viruses counteract the NMD pathway for successful amplification in host cells. A protein required for long-distance movement of Pea enation mosaic virus 2 (PEMV2) is shown to also protect both viral and host mRNAs from NMD. RNA-seq analyses of the Nicotiana benthamiana transcriptome revealed that PEMV2 infection significantly impairs the host NMD pathway. RNA viruses routinely induce large-scale changes in host gene expression, and, like PEMV2, may use NMD inhibition to alter the host transcriptome in an effort to increase virus amplification. Full Article
rom The Absence of (p)ppGpp Renders Initiation of Escherichia coli Chromosomal DNA Synthesis Independent of Growth Rates By mbio.asm.org Published On :: 2020-03-10T01:30:42-07:00 ABSTRACT The initiation of Escherichia coli chromosomal DNA replication starts with the oligomerization of the DnaA protein at repeat sequences within the origin (ori) region. The amount of ori DNA per cell directly correlates with the growth rate. During fast growth, the cell generation time is shorter than the time required for complete DNA replication; therefore, overlapping rounds of chromosome replication are required. Under these circumstances, the ori region DNA abundance exceeds the DNA abundance in the termination (ter) region. Here, high ori/ter ratios are found to persist in (p)ppGpp-deficient [(p)ppGpp0] cells over a wide range of balanced exponential growth rates determined by medium composition. Evidently, (p)ppGpp is necessary to maintain the usual correlation of slow DNA replication initiation with a low growth rate. Conversely, ori/ter ratios are lowered when cell growth is slowed by incrementally increasing even low constitutive basal levels of (p)ppGpp without stress, as if (p)ppGpp alone is sufficient for this response. There are several previous reports of (p)ppGpp inhibition of chromosomal DNA synthesis initiation that occurs with very high levels of (p)ppGpp that stop growth, as during the stringent starvation response or during serine hydroxamate treatment. This work suggests that low physiological levels of (p)ppGpp have significant functions in growing cells without stress through a mechanism involving negative supercoiling, which is likely mediated by (p)ppGpp regulation of DNA gyrase. IMPORTANCE Bacterial cells regulate their own chromosomal DNA synthesis and cell division depending on the growth conditions, producing more DNA when growing in nutritionally rich media than in poor media (i.e., human gut versus water reservoir). The accumulation of the nucleotide analog (p)ppGpp is usually viewed as serving to warn cells of impending peril due to otherwise lethal sources of stress, which stops growth and inhibits DNA, RNA, and protein synthesis. This work importantly finds that small physiological changes in (p)ppGpp basal levels associated with slow balanced exponential growth incrementally inhibit the intricate process of initiation of chromosomal DNA synthesis. Without (p)ppGpp, initiations mimic the high rates present during fast growth. Here, we report that the effect of (p)ppGpp may be due to the regulation of the expression of gyrase, an important enzyme for the replication of DNA that is a current target of several antibiotics. Full Article
rom Viral DNA Binding Protein SUMOylation Promotes PML Nuclear Body Localization Next to Viral Replication Centers By mbio.asm.org Published On :: 2020-03-17T01:30:14-07:00 ABSTRACT Human adenoviruses (HAdVs) have developed mechanisms to manipulate cellular antiviral measures to ensure proper DNA replication, with detailed processes far from being understood. Host cells repress incoming viral genomes through a network of transcriptional regulators that normally control cellular homeostasis. The nuclear domains involved are promyelocytic leukemia protein nuclear bodies (PML-NBs), interferon-inducible, dot-like nuclear structures and hot spots of SUMO posttranslational modification (PTM). In HAdV-infected cells, such SUMO factories are found in close proximity to newly established viral replication centers (RCs) marked by the adenoviral DNA binding protein (DBP) E2A. Here, we show that E2A is a novel target of host SUMOylation, leading to PTMs supporting E2A function in promoting productive infection. Our data show that SUMOylated E2A interacts with PML. Decreasing SUMO-E2A protein levels by generating HAdV variants mutated in the three main SUMO conjugation motifs (SCMs) led to lower numbers of viral RCs and PML-NBs, and these two structures were no longer next to each other. Our data further indicate that SUMOylated E2A binds the host transcription factor Sp100A, promoting HAdV gene expression, and represents the molecular bridge between PML tracks and adjacent viral RCs. Consequently, E2A SCM mutations repressed late viral gene expression and progeny production. These data highlight a novel mechanism used by the virus to benefit from host antiviral responses by exploiting the cellular SUMO conjugation machinery. IMPORTANCE PML nuclear bodies (PML-NBs) are implicated in general antiviral defense based on recruiting host restriction factors; however, it is not understood so far why viruses would establish viral replication centers (RCs) juxtaposed to such "antiviral" compartments. To understand this enigma, we investigate the cross talk between PML-NB components and viral RCs to find the missing link connecting both compartments to promote efficient viral replication and gene expression. Taken together, the current concept is more intricate than originally believed, since viruses apparently take advantage of several specific PML-NB-associated proteins to promote productive infection. Simultaneously, they efficiently inhibit antiviral measures to maintain the viral infectious program. Our data provide evidence that SUMOylation of the viral RC marker protein E2A represents the basis of this virus-host interface and regulates various downstream events to support HAdV productive infection. These results are the basis of our current attempts to generate and screen for specific E2A SUMOylation inhibitors to constitute novel therapeutic approaches to limit and prevent HAdV-mediated diseases and mortality of immunosuppressed patients. Full Article
rom Sulfamoyl Heteroarylcarboxylic Acids as Promising Metallo-{beta}-Lactamase Inhibitors for Controlling Bacterial Carbapenem Resistance By mbio.asm.org Published On :: 2020-03-17T01:30:15-07:00 ABSTRACT Production of metallo-β-lactamases (MBLs), which hydrolyze carbapenems, is a cause of carbapenem resistance in Enterobacteriaceae. Development of effective inhibitors for MBLs is one approach to restore carbapenem efficacy in carbapenem-resistant Enterobacteriaceae (CRE). We report here that sulfamoyl heteroarylcarboxylic acids (SHCs) can competitively inhibit the globally spreading and clinically relevant MBLs (i.e., IMP-, NDM-, and VIM-type MBLs) at nanomolar to micromolar orders of magnitude. Addition of SHCs restored meropenem efficacy against 17/19 IMP-type and 7/14 NDM-type MBL-producing Enterobacteriaceae to satisfactory clinical levels. SHCs were also effective against IMP-type MBL-producing Acinetobacter spp. and engineered Escherichia coli strains overproducing individual minor MBLs (i.e., TMB-2, SPM-1, DIM-1, SIM-1, and KHM-1). However, SHCs were less effective against MBL-producing Pseudomonas aeruginosa. Combination therapy with meropenem and SHCs successfully cured mice infected with IMP-1-producing E. coli and dually NDM-1/VIM-1-producing Klebsiella pneumoniae clinical isolates. X-ray crystallographic analyses revealed the inhibition mode of SHCs against MBLs; the sulfamoyl group of SHCs coordinated to two zinc ions, and the carboxylate group coordinated to one zinc ion and bound to positively charged amino acids Lys224/Arg228 conserved in MBLs. Preclinical testing revealed that the SHCs showed low toxicity in cell lines and mice and high stability in human liver microsomes. Our results indicate that SHCs are promising lead compounds for inhibitors of MBLs to combat MBL-producing CRE. IMPORTANCE Carbapenem antibiotics are the last resort for control of severe infectious diseases, bloodstream infections, and pneumonia caused by Gram-negative bacteria, including Enterobacteriaceae. However, carbapenem-resistant Enterobacteriaceae (CRE) strains have spread globally and are a critical concern in clinical settings because CRE infections are recognized as a leading cause of increased mortality among hospitalized patients. Most CRE produce certain kinds of serine carbapenemases (e.g., KPC- and GES-type β-lactamases) or metallo-β-lactamases (MBLs), which can hydrolyze carbapenems. Although effective MBL inhibitors are expected to restore carbapenem efficacy against MBL-producing CRE, no MBL inhibitor is currently clinically available. Here, we synthesized 2,5-diethyl-1-methyl-4-sulfamoylpyrrole-3-carboxylic acid (SPC), which is a potent inhibitor of MBLs. SPC is a remarkable lead compound for clinically useful MBL inhibitors and can potentially provide a considerable benefit to patients receiving treatment for lethal infectious diseases caused by MBL-producing CRE. Full Article
rom Metabolite Sequestration Enables Rapid Recovery from Fatty Acid Depletion in Escherichia coli By mbio.asm.org Published On :: 2020-03-17T01:30:15-07:00 ABSTRACT Microbes adapt their metabolism to take advantage of nutrients in their environment. Such adaptations control specific metabolic pathways to match energetic demands with nutrient availability. Upon depletion of nutrients, rapid pathway recovery is key to release cellular resources required for survival under the new nutritional conditions. Yet, little is known about the regulatory strategies that microbes employ to accelerate pathway recovery in response to nutrient depletion. Using the fatty acid catabolic pathway in Escherichia coli, here, we show that fast recovery can be achieved by rapid release of a transcriptional regulator from a metabolite-sequestered complex. With a combination of mathematical modeling and experiments, we show that recovery dynamics depend critically on the rate of metabolite consumption and the exposure time to nutrients. We constructed strains with rewired transcriptional regulatory architectures that highlight the metabolic benefits of negative autoregulation over constitutive and positive autoregulation. Our results have wide-ranging implications for our understanding of metabolic adaptations, as well as for guiding the design of gene circuitry for synthetic biology and metabolic engineering. IMPORTANCE Rapid metabolic recovery during nutrient shift is critical to microbial survival, cell fitness, and competition among microbiota, yet little is known about the regulatory mechanisms of rapid metabolic recovery. This work demonstrates a previously unknown mechanism where rapid release of a transcriptional regulator from a metabolite-sequestered complex enables fast recovery to nutrient depletion. The work identified key regulatory architectures and parameters that control the speed of recovery, with wide-ranging implications for the understanding of metabolic adaptations as well as synthetic biology and metabolic engineering. Full Article
rom Neutralizing Monoclonal Antibodies against the Gn and the Gc of the Andes Virus Glycoprotein Spike Complex Protect from Virus Challenge in a Preclinical Hamster Model By mbio.asm.org Published On :: 2020-03-24T01:31:00-07:00 ABSTRACT Hantaviruses are the etiological agent of hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). The latter is associated with case fatality rates ranging from 30% to 50%. HCPS cases are rare, with approximately 300 recorded annually in the Americas. Recently, an HCPS outbreak of unprecedented size has been occurring in and around Epuyén, in the southwestern Argentinian state of Chubut. Since November of 2018, at least 29 cases have been laboratory confirmed, and human-to-human transmission is suspected. Despite posing a significant threat to public health, no treatment or vaccine is available for hantaviral disease. Here, we describe an effort to identify, characterize, and develop neutralizing and protective antibodies against the glycoprotein complex (Gn and Gc) of Andes virus (ANDV), the causative agent of the Epuyén outbreak. Using murine hybridoma technology, we generated 19 distinct monoclonal antibodies (MAbs) against ANDV GnGc. When tested for neutralization against a recombinant vesicular stomatitis virus expressing the Andes glycoprotein (GP) (VSV-ANDV), 12 MAbs showed potent neutralization and 8 showed activity in an antibody-dependent cellular cytotoxicity reporter assay. Escape mutant analysis revealed that neutralizing MAbs targeted both the Gn and the Gc. Four MAbs that bound different epitopes were selected for preclinical studies and were found to be 100% protective against lethality in a Syrian hamster model of ANDV infection. These data suggest the existence of a wide array of neutralizing antibody epitopes on hantavirus GnGc with unique properties and mechanisms of action. IMPORTANCE Infections with New World hantaviruses are associated with high case fatality rates, and no specific vaccine or treatment options exist. Furthermore, the biology of the hantaviral GnGc complex, its antigenicity, and its fusion machinery are poorly understood. Protective monoclonal antibodies against GnGc have the potential to be developed into therapeutics against hantaviral disease and are also great tools to elucidate the biology of the glycoprotein complex. Full Article
rom Protein-Mediated and RNA-Based Origins of Replication of Extrachromosomal Mycobacterial Prophages By mbio.asm.org Published On :: 2020-03-24T01:31:01-07:00 ABSTRACT Temperate bacteriophages are common and establish lysogens of their bacterial hosts in which the prophage is stably inherited. It is typical for such prophages to be integrated into the bacterial chromosome, but extrachromosomally replicating prophages have been described also, with the best characterized being the Escherichia coli phage P1 system. Among the large collection of sequenced mycobacteriophages, more than half are temperate or predicted to be temperate, most of which code for a tyrosine or serine integrase that promotes site-specific prophage integration. However, within the large group of 621 cluster A temperate phages, ~20% lack an integration cassette, which is replaced with a parABS partitioning system. A subset of these phages carry genes coding for a RepA-like protein (RepA phages), which we show here is necessary and sufficient for autonomous extrachromosomal replication. The non-RepA phages appear to replicate using an RNA-based system, as a parABS-proximal region expressing a noncoding RNA is required for replication. Both RepA and non-RepA phage-based plasmids replicate at one or two copies per cell, transform both Mycobacterium smegmatis and Mycobacterium tuberculosis, and are compatible with pAL5000-derived oriM and integration-proficient plasmid vectors. Characterization of these phage-based plasmids offers insights into the variability of lysogenic maintenance systems and provides a large suite of plasmids for actinobacterial genetics that vary in stability, copy number, compatibility, and host range. IMPORTANCE Bacteriophages are the most abundant biological entities in the biosphere and are a source of uncharacterized biological mechanisms and genetic tools. Here, we identify segments of phage genomes that are used for stable extrachromosomal replication in the prophage state. Autonomous replication of some of these phages requires a RepA-like protein, although most lack repA and use RNA-based systems for replication initiation. We describe a suite of plasmids based on these prophage replication functions that vary in copy number, stability, host range, and compatibility. These plasmids expand the toolbox available for genetic manipulation of Mycobacterium and other Actinobacteria, including Gordonia terrae. Full Article
rom Characterization of the Efflux Capability and Substrate Specificity of Aspergillus fumigatus PDR5-like ABC Transporters Expressed in Saccharomyces cerevisiae By mbio.asm.org Published On :: 2020-03-24T01:31:01-07:00 ABSTRACT This research analyzed six Aspergillus fumigatus genes encoding putative efflux proteins for their roles as transporters. The A. fumigatus genes abcA, abcC, abcF, abcG, abcH, and abcI were cloned into plasmids and overexpressed in a Saccharomyces cerevisiae strain in which the highly active endogenous ABC transporter gene PDR5 was deleted. The activity of each transporter was measured by efflux of rhodamine 6G and accumulation of alanine β-naphthylamide. The transporters AbcA, AbcC, and AbcF had the strongest efflux activities of these compounds. All of the strains with plasmid-expressed transporters had more efflux activity than did the PDR5-deleted background strain. We performed broth microdilution drug susceptibility testing and agar spot assays using an array of compounds and antifungal drugs to determine the transporter specificity and drug susceptibility of the strains. The transporters AbcC and AbcF showed the broadest range of substrate specificity, while AbcG and AbcH had the narrowest range of substrates. Strains expressing the AbcA, AbcC, AbcF, or AbcI transporter were more resistant to fluconazole than was the PDR5-deleted background strain. Strains expressing AbcC and AbcF were additionally more resistant to clotrimazole, itraconazole, ketoconazole, and posaconazole than was the background strain. Finally, we analyzed the expression levels of the genes by reverse transcription-quantitative PCR (RT-qPCR) in triazole-susceptible and -resistant A. fumigatus clinical isolates. All of these transporters are expressed at a measurable level, and transporter expression varied significantly between strains, demonstrating the high degree of phenotypic variation, plasticity, and divergence of which this species is capable. IMPORTANCE One mechanism behind drug resistance is altered export out of the cell. This work is a multifaceted analysis of membrane efflux transporters in the human fungal pathogen A. fumigatus. Bioinformatics evidence infers that there is a relatively large number of genes in A. fumigatus that encode ABC efflux transporters. However, very few of these transporters have been directly characterized and analyzed for their potential role in drug resistance. Our objective was to determine if these undercharacterized proteins function as efflux transporters and then to better define whether their efflux substrates include antifungal drugs used to treat fungal infections. We chose six A. fumigatus potential plasma membrane ABC transporter genes for analysis and found that all six genes produced functional transporter proteins. We used two fungal systems to look for correlations between transporter function and drug resistance. These transporters have the potential to produce drug-resistant phenotypes in A. fumigatus. Continued characterization of these and other transporters may assist in the development of efflux inhibitor drugs. Full Article
rom Report from the American Society for Microbiology COVID-19 International Summit, 23 March 2020: Value of Diagnostic Testing for SARS-CoV-2/COVID-19 By mbio.asm.org Published On :: 2020-03-26T14:58:07-07:00 Full Article
rom Single-Dose, Intranasal Immunization with Recombinant Parainfluenza Virus 5 Expressing Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Spike Protein Protects Mice from Fatal MERS-CoV Infection By mbio.asm.org Published On :: 2020-04-07T01:31:16-07:00 ABSTRACT Middle East respiratory syndrome coronavirus (MERS-CoV) can cause severe and fatal acute respiratory disease in humans and remains endemic in the Middle East since first being identified in 2012. There are currently no approved vaccines or therapies available for MERS-CoV. In this study, we evaluated parainfluenza virus 5 (PIV5)-based vaccine expressing the MERS-CoV envelope spike protein (PIV5/MERS-S) in a human DPP4 knockin C57BL/6 congenic mouse model (hDPP4 KI). Following a single-dose intranasal immunization, PIV5-MERS-S induced neutralizing antibody and robust T cell responses in hDPP4 KI mice. A single intranasal administration of 104 PFU PIV5-MERS-S provided complete protection against a lethal challenge with mouse-adapted MERS-CoV (MERSMA6.1.2) and improved virus clearance in the lung. In comparison, single-dose intramuscular immunization with 106 PFU UV-inactivated MERSMA6.1.2 mixed with Imject alum provided protection to only 25% of immunized mice. Intriguingly, an influx of eosinophils was observed only in the lungs of mice immunized with inactivated MERS-CoV, suggestive of a hypersensitivity-type response. Overall, our study indicated that PIV5-MERS-S is a promising effective vaccine candidate against MERS-CoV infection. IMPORTANCE MERS-CoV causes lethal infection in humans, and there is no vaccine. Our work demonstrates that PIV5 is a promising vector for developing a MERS vaccine. Furthermore, success of PIV5-based MERS vaccine can be employed to develop a vaccine for emerging CoVs such as SARS-CoV-2, which causes COVID-19. Full Article
rom Romo1-Derived Antimicrobial Peptide Is a New Antimicrobial Agent against Multidrug-Resistant Bacteria in a Murine Model of Sepsis By mbio.asm.org Published On :: 2020-04-14T01:31:22-07:00 ABSTRACT To overcome increasing bacterial resistance to conventional antibiotics, many antimicrobial peptides (AMPs) derived from host defense proteins have been developed. However, there are considerable obstacles to their application to systemic infections because of their low bioavailability. In the present study, we developed an AMP derived from Romo1 (AMPR-11) that exhibits a broad spectrum of antimicrobial activity. AMPR-11 showed remarkable efficacy against sepsis-causing bacteria, including multidrug-resistant strains, with low toxicity in a murine model of sepsis after intravenous administration. It seems that AMPR-11 disrupts bacterial membranes by interacting with cardiolipin and lipid A. From the results of this study, we suggest that AMPR-11 is a new class of agent for overcoming low efficacy in the intravenous application of AMPs and is a promising candidate to overcome multidrug resistance. IMPORTANCE Abuse of antibiotics often leads to increase of multidrug-resistant (MDR) bacteria, which threatens the life of human beings. To overcome threat of antibiotic resistance, scientists are developing a novel class of antibiotics, antimicrobial peptides, that can eradicate MDR bacteria. Unfortunately, these antibiotics have mainly been developed to cure bacterial skin infections rather than others, such as life-threatening sepsis. Major pharmaceutical companies have tried to develop antiseptic drugs; however, they have not been successful. Here, we report that AMPR-11, the antimicrobial peptide (AMP) derived from mitochondrial nonselective channel Romo1, has antimicrobial activity against Gram-positive and Gram-negative bacteria comprising many clinically isolated MDR strains. Moreover, AMPR-11 increased the survival rate in a murine model of sepsis caused by MDR bacteria. We propose that AMPR-11 could be a novel antiseptic drug candidate with a broad antimicrobial spectrum to overcome MDR bacterial infection. Full Article
rom Processing, Export, and Identification of Novel Linear Peptides from Staphylococcus aureus By mbio.asm.org Published On :: 2020-04-14T01:31:22-07:00 ABSTRACT Staphylococcus aureus can colonize the human host and cause a variety of superficial and invasive infections. The success of S. aureus as a pathogen derives from its ability to modulate its virulence through the release, sensing of and response to cyclic signaling peptides. Here we provide, for the first time, evidence that S. aureus processes and secretes small linear peptides through a specialized pathway that converts a lipoprotein leader into an extracellular peptide signal. We have identified and confirmed the machinery for each step and demonstrate that the putative membrane metalloprotease Eep and the EcsAB transporter are required to complete the processing and secretion of the peptides. In addition, we have identified several linear peptides, including the interspecies signaling molecule staph-cAM373, that are dependent on this processing and secretion pathway. These findings are particularly important because multiple Gram-positive bacteria rely on small linear peptides to control bacterial gene expression and virulence. IMPORTANCE Here, we provide evidence indicating that S. aureus secretes small linear peptides into the environment via a novel processing and secretion pathway. The discovery of a specialized pathway for the production of small linear peptides and the identification of these peptides leads to several important questions regarding their role in S. aureus biology, most interestingly, their potential to act as signaling molecules. The observations in this study provide a foundation for further in-depth studies into the biological activity of small linear peptides in S. aureus. Full Article
rom Conductance Mechanisms of Rapidly Desensitizing Cation Channelrhodopsins from Cryptophyte Algae By mbio.asm.org Published On :: 2020-04-21T01:31:26-07:00 ABSTRACT Channelrhodopsins guide algal phototaxis and are widely used as optogenetic probes for control of membrane potential with light. "Bacteriorhodopsin-like" cation channelrhodopsins (BCCRs) from cryptophytes differ in primary structure from other CCRs, lacking usual residues important for their cation conductance. Instead, the sequences of BCCR match more closely those of rhodopsin proton pumps, containing residues responsible for critical proton transfer reactions. We report 19 new BCCRs which, together with the earlier 6 known members of this family, form three branches (subfamilies) of a phylogenetic tree. Here, we show that the conductance mechanisms in two subfamilies differ with respect to involvement of the homolog of the proton donor in rhodopsin pumps. Two BCCRs from the genus Rhodomonas generate photocurrents that rapidly desensitize under continuous illumination. Using a combination of patch clamp electrophysiology, absorption, Raman spectroscopy, and flash photolysis, we found that the desensitization is due to rapid accumulation of a long-lived nonconducting intermediate of the photocycle with unusually blue-shifted absorption with a maximum at 330 nm. These observations reveal diversity within the BCCR family and contribute to deeper understanding of their independently evolved cation channel function. IMPORTANCE Cation channelrhodopsins, light-gated channels from flagellate green algae, are extensively used as optogenetic photoactivators of neurons in research and recently have progressed to clinical trials for vision restoration. However, the molecular mechanisms of their photoactivation remain poorly understood. We recently identified cryptophyte cation channelrhodopsins, structurally different from those of green algae, which have separately evolved to converge on light-gated cation conductance. This study reveals diversity within this new protein family and describes a subclade with unusually rapid desensitization that results in short transient photocurrents in continuous light. Such transient currents have not been observed in the green algae channelrhodopsins and are potentially useful in optogenetic protocols. Kinetic UV-visible (UV-vis) spectroscopy and photoelectrophysiology reveal that the desensitization is caused by rapid accumulation of a nonconductive photointermediate in the photochemical reaction cycle. The absorption maximum of the intermediate is 330 nm, the shortest wavelength reported in any rhodopsin, indicating a novel chromophore structure. Full Article
rom Structural Analysis of an L-Cysteine Desulfurase from an Ssp DNA Phosphorothioation System By mbio.asm.org Published On :: 2020-04-28T01:30:42-07:00 ABSTRACT DNA phosphorothioate (PT) modification, in which the nonbridging oxygen in the sugar-phosphate backbone is substituted by sulfur, is catalyzed by DndABCDE or SspABCD in a double-stranded or single-stranded manner, respectively. In Dnd and Ssp systems, mobilization of sulfur in PT formation starts with the activation of the sulfur atom of cysteine catalyzed by the DndA and SspA cysteine desulfurases, respectively. Despite playing the same biochemical role, SspA cannot be functionally replaced by DndA, indicating its unique physiological properties. In this study, we solved the crystal structure of Vibrio cyclitrophicus SspA in complex with its natural substrate, cysteine, and cofactor, pyridoxal phosphate (PLP), at a resolution of 1.80 Å. Our solved structure revealed the molecular mechanism that SspA employs to recognize its cysteine substrate and PLP cofactor, suggesting a common binding mode shared by cysteine desulfurases. In addition, although the distance between the catalytic Cys314 and the substrate cysteine is 8.9 Å, which is too far for direct interaction, our structural modeling and biochemical analysis revealed a conformational change in the active site region toward the cysteine substrate to move them close to each other to facilitate the nucleophilic attack. Finally, the pulldown analysis showed that SspA could form a complex with SspD, an ATP pyrophosphatase, suggesting that SspD might potentially accept the activated sulfur atom directly from SspA, providing further insights into the biochemical pathway of Ssp-mediated PT modification. IMPORTANCE Apart from its roles in Fe-S cluster assembly, tRNA thiolation, and sulfur-containing cofactor biosynthesis, cysteine desulfurase serves as a sulfur donor in the DNA PT modification, in which a sulfur atom substitutes a nonbridging oxygen in the DNA phosphodiester backbone. The initial sulfur mobilization from l-cysteine is catalyzed by the SspA cysteine desulfurase in the SspABCD-mediated DNA PT modification system. By determining the crystal structure of SspA, the study presents the molecular mechanism that SspA employs to recognize its cysteine substrate and PLP cofactor. To overcome the long distance (8.9 Å) between the catalytic Cys314 and the cysteine substrate, a conformational change occurs to bring Cys314 to the vicinity of the substrate, allowing for nucleophilic attack. Full Article
rom Novel Divisome-Associated Protein Spatially Coupling the Z-Ring with the Chromosomal Replication Terminus in Caulobacter crescentus By mbio.asm.org Published On :: 2020-04-28T01:30:42-07:00 ABSTRACT Cell division requires proper spatial coordination with the chromosome, which undergoes dynamic changes during chromosome replication and segregation. FtsZ is a bacterial cytoskeletal protein that assembles into the Z-ring, providing a platform to build the cell division apparatus. In the model bacterium Caulobacter crescentus, the cellular localization of the Z-ring is controlled during the cell cycle in a chromosome replication-coupled manner. Although dynamic localization of the Z-ring at midcell is driven primarily by the replication origin-associated FtsZ inhibitor MipZ, the mechanism ensuring accurate positioning of the Z-ring remains unclear. In this study, we showed that the Z-ring colocalizes with the replication terminus region, located opposite the origin, throughout most of the C. crescentus cell cycle. Spatial organization of the two is mediated by ZapT, a previously uncharacterized protein that interacts with the terminus region and associates with ZapA and ZauP, both of which are part of the incipient division apparatus. While the Z-ring and the terminus region coincided with the presence of ZapT, colocalization of the two was perturbed in cells lacking zapT, which is accompanied by delayed midcellular positioning of the Z-ring. Moreover, cells overexpressing ZapT showed compromised positioning of the Z-ring and MipZ. These findings underscore the important role of ZapT in controlling cell division processes. We propose that ZapT acts as a molecular bridge that physically links the terminus region to the Z-ring, thereby ensuring accurate site selection for the Z-ring. Because ZapT is conserved in proteobacteria, these findings may define a general mechanism coordinating cell division with chromosome organization. IMPORTANCE Growing bacteria require careful tuning of cell division processes with dynamic organization of replicating chromosomes. In enteric bacteria, ZapA associates with the cytoskeletal Z-ring and establishes a physical linkage to the chromosomal replication terminus through its interaction with ZapB-MatP-DNA complexes. However, because ZapB and MatP are found only in enteric bacteria, it remains unclear how the Z-ring and the terminus are coordinated in the vast majority of bacteria. Here, we provide evidence that a novel conserved protein, termed ZapT, mediates colocalization of the Z-ring with the terminus in Caulobacter crescentus, a model organism that is phylogenetically distant from enteric bacteria. Given that ZapT facilitates cell division processes in C. crescentus, this study highlights the universal importance of the physical linkage between the Z-ring and the terminus in maintaining cell integrity. Full Article
rom US pedestrian deaths from vehicle crashes increasing in 30 states By thenationshealth.aphapublications.org Published On :: 2020-05-01T05:00:17-07:00 Pedestrian fatalities from vehicle impacts in 2019 were the highest in the U.S. in over three decades, a February report finds. Full Article
rom Long-acting, Injectable Buprenorphine: Great Promise, but Significant Barriers to Use By www.ncmedicaljournal.com Published On :: 2020-05-04T06:50:30-07:00 To the Editor—A 30-day injectable form of buprenorphine branded as SublocadeTM (Buprenorphine XR SQ) was approved by the FDA in 2017. This medication is administered by a health care professional subcutaneously in the abdomen to treat opioid use disorder. This long-acting delivery system holds great promise for many patients who have barriers to taking daily transmucosal buprenorphine-containing medications such as those with poor adherence to a daily medication. It is beneficial for those who have difficulty safely storing their medications, including patients who have children in the home, unstable housing, or live with others who have a use disorder. This product is also an option for patients who prefer mono-product buprenorphine. As Buprenorphine XR SQ is administered directly by a health care professional, it does not contain the abuse-deterrent naloxone that some patients feel causes side effects. There are two ways to acquire Buprenorphine XR SQ: 1) order product from the distributor (buy and bill); or 2) dispensed from a specialty pharmacy for a specific patient (specialty pharmacy) [1]. For the buy and bill option, the health care setting must be certified through the Risk Evaluation and Mitigation Strategy (REMS) program and adhere to dispensing regulations [2]. We found this challenging to implement in the outpatient setting, thus we pursued the specialty pharmacy option. It ultimately took us nearly one year to complete the process. The following are the barriers we faced with our first attempt. As a controlled substance, the medication must be stored in a refrigerated lockbox. Before... Full Article
rom Place Matters: From Health and Health Care Disparities to Equity and Liberation By www.ncmedicaljournal.com Published On :: 2020-05-04T06:50:30-07:00 Place—a confluence of the social, economic, political, physical, and built environments—is fundamental to our understanding of health and health inequities among marginalized racial groups in the United States. Moreover, racism, defined as a system of structuring opportunity and assigning value based on the social interpretation of how one looks (i.e., race), has shaped the places people live in North Carolina. This problem is deeply imbedded in all of our systems, from housing to health care, affecting the ability of every resident of the state to flourish and thrive. Full Article