Massive pulmonary embolism (hemodynamically unstable, defined as systolic BP <90 mmHg) has significant morbidity and mortality. Point of care ultrasound (POCUS) has allowed clinicians to detect evidence of massive pulmonary embolism much earlier in the patient's clinical course, especially when patient instability precludes computerized tomography confirmation. POCUS detection of massive pulmonary embolism has traditionally been performed by physicians.
View Article and Find Full Text PDFWe discuss a patient with a penetrating knife wound to the chest who lost pulses from cardiac tamponade. Prehospital ultrasound was able to quickly identify the tamponade and a pericardiocentesis was performed using a Simplified Pneumothorax Emergency Air Release (SPEARTM) Needle (North American Rescue, LLC, USA) with subsequent return of spontaneous circulation. Penetrating chest trauma carries significant morbidity and mortality.
View Article and Find Full Text PDFAntimicrob Agents Chemother
January 2017
GS-9620 is a potent and selective oral Toll-like receptor 7 (TLR7) agonist that directly activates plasmacytoid dendritic cells (pDCs). GS-9620 suppressed hepatitis B virus (HBV) in animal models of chronic infection and transiently activated HIV expression ex vivo in latently infected peripheral blood mononuclear cells (PBMCs) from virally suppressed patients. Currently, GS-9620 is under clinical evaluation for treating chronic HBV infection and for reducing latent reservoirs in virally suppressed HIV-infected patients.
View Article and Find Full Text PDFBictegravir (BIC; GS-9883), a novel, potent, once-daily, unboosted inhibitor of HIV-1 integrase (IN), specifically targets IN strand transfer activity (50% inhibitory concentration [IC] of 7.5 ± 0.3 nM) and HIV-1 integration in cells.
View Article and Find Full Text PDFThe use of nonhuman primate (NHP) models to study persistent residual virus and viral eradication strategies in combination antiretroviral therapy (cART)-treated individuals requires regimens that effectively suppress SIV replication to clinically relevant levels in macaques. We developed and evaluated two novel cART regimens in SIVmac239-infected rhesus macaques: (1) a "triple regimen" containing the nucleo(s/t)ide reverse transcriptase inhibitors emtricitabine (FTC) and tenofovir disoproxil fumarate [TDF, prodrug of tenofovir (TFV, PMPA)] with the integrase strand transfer inhibitor dolutegravir (DTG) (n = 3), or (2) a "quad regimen" containing the same three drugs plus the protease inhibitor darunavir (DRV) (n = 3), with each regimen coformulated for convenient administration by a single daily subcutaneous injection. Plasma drug concentrations were consistent across animals within the triple and quad regimen-treated groups, although DTG levels were lower in the quad regimen animals.
View Article and Find Full Text PDFScreening of a marine natural products library afforded three new analogues of the tetronic acid containing polyketide abyssomicin family and identified abyssomicin 2 as a selective reactivator of latent HIV virus. Examination of the mode of action of this new latent HIV reactivating agent demonstrated that it functions via a distinct mechanism compared to that of existing reactivating agents and is effective at reactivating latent virus in a subset of primary patient cell lines.
View Article and Find Full Text PDFAn extract of Humicola fuscoatra (UCSC strain no. 108111A) was shown to reactivate latent HIV-1 expression in an in vitro model of central memory CD4+ T cells. We report the bioassay-guided isolation and structure determination of several resorcyclic acid lactones, including four known compounds, radicicol (1, aka.
View Article and Find Full Text PDFtert-Butoxy-(4-phenyl-quinolin-3-yl)-acetic acids (tBPQA) are a new class of HIV-1 integrase (IN) inhibitors that are structurally distinct from IN strand transfer inhibitors but analogous to LEDGINs. LEDGINs are a class of potent antiviral compounds that interacts with the lens epithelium-derived growth factor (LEDGF) binding pocket on IN and were identified through competition binding against LEDGF. LEDGF tethers IN to the host chromatin and enables targeted integration of viral DNA.
View Article and Find Full Text PDFElvitegravir is a strand transfer inhibitor of HIV-1 integrase that is currently undergoing phase 3 clinical testing. The two predominant metabolites of elvitegravir, M1 and M4 (elvitegravir hydroxide and elvitegravir glucuronide), have been shown to inhibit HIV-1 integrase in vitro. While they are markedly less potent than elvitegravir and present only at low levels in plasma clinically, we investigated their potential to select for elvitegravir resistance in vitro.
View Article and Find Full Text PDFWe have developed a homogeneous time-resolved fluorescence resonance energy transfer (FRET)-based assay that detects the formation of HIV-1 integrase (IN) dimers. The assay utilizes IN monomers that express two different epitope tags that are recognized by their respective antibodies, coupled to distinct fluorophores. Surprisingly, we found that dithiothreitol (DTT), a reducing agent essential for in vitro enzymatic activity of IN, weakened the interaction between IN monomers.
View Article and Find Full Text PDFThe interaction between lens epithelium-derived growth factor/transcriptional co-activator p75 (LEDGF) and human immunodeficiency virus type 1 (HIV-1) integrase (IN) is essential for HIV-1 replication. Homogeneous time-resolved fluorescence resonance energy transfer assays were developed to characterize HIV-1 integrase dimerization and the interaction between LEDGF and IN dimers. Using these assays in an equilibrium end point dose-response format with mathematical modeling, we determined the dissociation constants of IN dimers (K(dimer) = 67.
View Article and Find Full Text PDFHIV-1 integration into the host cell genome is a multistep process catalyzed by the virally-encoded integrase (IN) protein. In view of the difficulty of obtaining a stable DNA-bound IN at high concentration as required for structure determination, we selected IN-DNA complexes that form disulfide linkages between 5'-thiolated DNA and several single mutations to cysteine around the catalytic site of IN. Mild reducing conditions allowed for selection of the most thermodynamically-stable disulfide-linked species.
View Article and Find Full Text PDFAntimicrob Agents Chemother
March 2009
GS-9160 is a novel and potent inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase (IN) that specifically targets the process of strand transfer. It is an authentic inhibitor of HIV-1 integration, since treatment of infected cells results in an elevation of two-long terminal repeat circles and a decrease of integration junctions. GS-9160 has potent and selective antiviral activity in primary human T lymphocytes producing a 50% effective concentration (EC(50)) of approximately 2 nM, with a selectivity index (50% cytotoxic concentration/EC(50)) of approximately 2,000.
View Article and Find Full Text PDFElevated arsenic concentrations are common in water recovered from aquifer storage and recovery (ASR) systems in west-central Florida that store surface water. Investigations of the Suwannee Limestone of the Upper Floridan aquifer, the storage zone for ASR systems, have shown that arsenic is highest in pyrite in zones of high moldic porosity. Geochemical modeling was employed to examine pyrite stability in limestone during simulated injections of surface water into wells open only to the Suwannee Limestone with known mineralogy and water chemistry.
View Article and Find Full Text PDFLEDGF/p75 is known to enhance the integrase strand transfer activity in vitro, but the underlying mechanism is unclear. Using an integrase assay with a chemiluminescent readout adapted to a 96-well plate format, the effect of LEDGF/p75 on both the 3'-processing and strand transfer steps was analyzed. Integrase inhibitors of the strand transfer reaction remained active in the presence of LEDGF/p75, but displayed 3- to 7-fold higher IC50 values.
View Article and Find Full Text PDFObjectives: The purpose of this study was to determine the prevalence and spectrum of nonsynonymous polymorphisms (amino acid variants) in the cardiac sodium channel among healthy subjects.
Background: Pathogenic mutations in the cardiac sodium channel gene, SCN5A, cause approximately 15 to 20% of Brugada syndrome (BrS1), 5 to 10% of long QT syndrome (LQT3), and 2 to 5% of sudden infant death syndrome.
Methods: Using single-stranded conformation polymorphism, denaturing high-performance liquid chromatography, and/or direct DNA sequencing, mutational analysis of the protein-encoding exons of SCN5A was performed on 829 unrelated, anonymous healthy subjects: 319 black, 295 white, 112 Asian, and 103 Hispanic.
Objective: To determine the spectrum, frequency, and ethnic-specificity of channel variants in the potassium channel genes implicated in congenital long QT syndrome (LQTS) among healthy subjects.
Subjects And Methods: Genomic DNA from 744 apparently healthy individuals-305 black, 187 white, 134 Asian, and 118 Hispanic--was subject to a comprehensive mutational analysis of the 4 LQTS-causing potassium channel genes: KCNQ1 (LQT1), KCNH2 (LQT2), KCNE1 (LQT5), and KCNE2 (LQT6).
Results: Overall, 49 distinct amino acid-altering variants (36 novel) were identified: KCNQ1 (n = 16), KCNH2 (n = 25),KCNE1 (n = 5), and KCNE2 (n = 3).