Population Pharmacokinetic Modeling of VL-2397, a Novel Systemic Antifungal Agent: Analysis of a Single- and Multiple-Ascending-Dose Study in Healthy Subjects.

VL-2397, a novel, systemic antifungal agent, has potent in vitro and in vivo fungicidal activity against Aspergillus species. Plasma concentrations from a phase 1 study were used to construct a population pharmacokinetic (PPK) model for VL-2397. Healthy subjects aged 18 to 55 years received single doses of VL-2397, ranging from 3 to 1,200 mg, multiple daily doses of 300, 600, or 1,200 mg for 7 days, or 300 mg three times/day for 7 days followed by 600 mg daily for 21 days. Plasma samples were collected throughout the dosing intervals. Sixty-six subjects provided 1,908 concentrations. Drug concentrations over time were increased less than dose proportionally for doses above 30 mg. Dose-normalized concentrations plotted over time did not overlap. A 3-compartment nonlinear saturable binding model fit the data well. Clearance increased with dose, and mean values ranged from 0.4 liters/h at 3 mg to 8.5 liters/h at 1,200 mg. Mean volume in the central compartment ranged from 4.8 to 6.9 liters across doses. In the first 24 h, once-daily dosing results in a rapid decrease in concentrations by hour 16 to approximately 1 mg/liter, regardless of dose, with slow clearance over time. Administration of 300 mg every 8 h achieved concentrations above 1 mg/liter over an entire 24-h period. There was a significant relationship between body surface area and clearance. The data suggest that VL-2397 has nonlinear saturable binding kinetics. Protein binding is the likely primary source of the nonlinearity. The PPK model can now be used to optimize dosing by bridging the kinetics to efficacious pharmacodynamic targets.

The Siderophore Transporter Sit1 Determines Susceptibility to the Antifungal VL-2397.

VL-2397 (previously termed ASP2397) is an antifungal, aluminum-chelating cyclic hexapeptide with a structure analogous to that of ferrichrome-type siderophores, whereby replacement of aluminum by iron was shown to decrease the antifungal activity of this compound. Here, we found that inactivation of an importer for ferrichrome-type siderophores, termed Sit1, renders Aspergillus fumigatus resistant to VL-2397. Moreover, expression of the endogenous sit1 gene under the control of a xylose-inducible promoter (to uncouple sit1 expression from iron repression) combined with C-terminal tagging with a fluorescent protein demonstrated localization of Sit1 in the plasma membrane and xylose-dependent VL-2397 susceptibility. This underlines that Sit1-mediated uptake is essential for VL-2397 susceptibility. Under xylose-induced sit1 expression, VL-2397 also retained antifungal activity after replacing aluminum with iron, which demonstrates that VL-2397 bears antifungal activity independent of cellular aluminum importation. Analysis of sit1 expression indicated that the reduced antifungal activity of the iron-chelated VL-2397 is caused by downregulation of sit1 expression by the imported iron. Furthermore, we demonstrate that defects in iron homeostatic mechanisms modulate the activity of VL-2397. In contrast to A. fumigatus and Candida glabrata, Saccharomyces cerevisiae displays intrinsic resistance to VL-2397 antifungal activity. However, expression of sit1 from A. fumigatus, or its homologue from C. glabrata, resulted in susceptibility to VL-2397, which suggests that the intrinsic resistance of S. cerevisiae is based on lack of uptake and that A. fumigatus, C. glabrata, and S. cerevisiae share an intracellular target for VL-2397.

First-in-Human Phase 1 Study To Assess Safety, Tolerability, and Pharmacokinetics of a Novel Antifungal Drug, VL-2397, in Healthy Adults.

VL-2397 is an antifungal drug with a novel mechanism of action, rapid fungicidal in vitro activity, and potent in vivo activity against Aspergillus fumigatus, including azole-resistant strains. VL2397-101, a phase 1 first-in-human, randomized, double-blind, placebo-controlled dose-escalation study, was conducted in healthy adults to determine the safety, tolerability, and pharmacokinetics (PK) of single and multiple ascending intravenous (i.v.) doses of VL-2397. All dosing cohorts were fully enrolled; all subjects completed the safety follow-up. A safety committee reviewed the safety data for each dosing cohort prior to recommending the initiation of each subsequent cohort. No serious adverse events (SAEs) occurred; the majority of treatment-emergent adverse events (TEAEs) were mild and self-limited. The most common drug-related TEAEs were infusion site reactions. No clinically concerning trends were noted in vital signs, electrocardiograms, physical examinations, or safety laboratory results. Following single infusions of VL-2397, the overall and maximum exposures rose less than proportionally with increasing doses from 3 mg to 1,200 mg as indicated by area under the concentration-time curve over 24 h (AUC24) and maximum concentration (Cmax). No signs of VL-2397 accumulation were observed following i.v. infusions of 300, 600, and 1,200 mg every 24 h (q24h) for 7 days. Renal elimination played a major role in total body clearance, with up to 47% of unmetabolized drug in urine 24 h after administration at single doses of >30 mg. Overall, VL-2397 dosing in the study appeared to be safe and well tolerated in the healthy subjects. The safety profile, consistent PK, and lack of drug accumulation support further development of VL-2397 in patients with invasive aspergillosis.

Examining spatiotemporal variability of urban particulate matter and application of high-time resolution data from a network of low-cost air pollution sensors.

Traditional air monitoring approaches using regulatory monitors have historically been used to assess regional-scale trends in air pollutants across large geographical areas. Recent advances in air pollution sensor technologies could provide additional information about nearby sources, support the siting of regulatory monitoring stations, and improve our knowledge of finer-scale spatiotemporal variation of ambient air pollutants and their associated health effects. Sensors are now being developed that are much smaller and lower cost than traditional ambient air monitoring systems and are capable of being deployed as a network to provide greater coverage of a given area. The CitySpace project conducted by the US EPA and the Shelby County Health Department included the deployment of a network of 17 sensor pods using Alphasense OPC-N2 particulate matter (PM) sensors integrated with meteorological sensors in Memphis, TN for six months. Sensor pods were collocated with a federal equivalent method (FEM) tapered element oscillating microbalance (TEOM) monitor both before and after the primary study period. Six of the sensor pods were found to meet the data quality objective (DQO) of coefficient of determination (R2) greater than 0.5 when collocated with the TEOM. Seven pods were decommissioned before the end of the study due to mechanical failure. The six pods meeting the DQO were used to examine the spatiotemporal variability of fine PM (PM2.5) across the Memphis area. One site was found to have higher relative PM2.5 concentrations when compared to the other sites in the network. The 1-min data from this sensor pod were evaluated to quantify the regional urban background and local-scale contributions to PM2.5 at that monitoring location. This method found that approximately 20% of the PM2.5 was attributed to local sources at this location, compared to 9% at a local regulatory monitoring site. Additionally, the 1-min data were combined with 1-min wind speed and wind direction data to examine potential sources in the area using the nonparametric trajectory analysis (NTA) technique. This method geographically identified local source areas that contributed to the measured concentrations at the high reading sensor location throughout the course of the study.

TP53 suppression promotes erythropoiesis in del(5q) MDS, suggesting a targeted therapeutic strategy in lenalidomide-resistant patients.

Stabilization of p53 in erythroid precursors in response to nucleosomal stress underlies the hypoplastic anemia in myelodysplastic syndromes (MDS) with chromosome 5q deletion [del(5q)]. We investigated whether cenersen, a clinically active 20-mer antisense oligonucleotide complementary to TP53 exon10, could suppress p53 expression and restore erythropoiesis in del(5q) MDS. Cenersen treatment of ribosomal protein S-14-deficient erythroblasts significantly reduced cellular p53 and p53-up-regulated modulator of apoptosis expression compared with controls, accompanied by a significant reduction in apoptosis and increased cell proliferation. In a two-stage erythroid differentiation assay, cenersen significantly suppressed nuclear p53 in bone marrow CD34+ cells isolated from patients with del(5q) MDS, whereas erythroid burst recovery increased proportionally to the magnitude of p53 suppression without evidence of del(5q) clonal suppression (r = -0.6; P = 0.005). To explore the effect of p53 suppression on erythropoiesis in vivo, dexamethasone, a glucocorticoid receptor-dependent p53 antagonist, was added to lenalidomide treatment in eight lower-risk, transfusion-dependent, del(5q) MDS patients with acquired drug resistance. Transfusion independence was restored in five patients accompanied by expansion of erythroid precursors and decreased cellular p53 expression. We conclude that targeted suppression of p53 could support effective erythropoiesis in lenalidomide-resistant del(5q) MDS.

Vascularized plantar myocutaneous free flap transfer for amputee stump preparation: a proof of concept cadaver study.

Lower extremity amputee stump ulceration, irritation, and pain have been a deterrent to consistent long-term or continuous use of lower extremity prosthetics. This study is the first in a series that hypothesizes that these complications can be minimized through the insetting of a vascularized plantar free flap (VPFF) on the amputee stump. Using three hip disarticulated cadaver specimens, a VPFF was designed, dissected, and implanted on one transfemoral and two transtibial stumps. Using accepted vascular anastomosis techniques, the posterior tibial artery was anastomosed to the distal femoral or popliteal artery with corresponding anastomoses for venous drainage. In addition, the possibility of a limited to partial sensate flap may be created with a neurorrhaphy of the associated nerves. This potentially sensate area would provide plantar skin that aids the existing local sensate flap used to close the defect. It is hypothesized that this procedure offers significant rehabilitative and long-term benefits to battlefield or other acute causes for lower extremity amputation. The procedure can be accomplished in battlefield surgical setting as an immediate or delayed inset for some but not all traumatic amputations. Salvaging a partial or complete VPFF from a traumatized foot will obviously be predicated on the degree of trauma to the donor tissue.

Dataset of atmospheric concentrations of polycyclic aromatic hydrocarbons in the Memphis Tri-state Area.

This dataset contains concentrations (in ng/m3) of 32 polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-state Area (MTA). In the atmosphere, PAHs are toxic pollutants emitted from incomplete combustion sources. This monitoring campaign was conducted at 19 sites in three neighboring counties in Tennessee, Mississippi, and Arkansas, i.e., MTA, over one year. The monitoring sites represented industrial, urban, suburban, and remote land types. Total suspended particulate (TSP) samples were collected at each site using a high-volume sampler every 12 days from March 13th, 2018, to May 25th, 2019. The collection media consisted of a quartz fiber filter (QFF) and a glass thimble containing polyurethane foam (PUF) and XAD-4 resin that collected particulate- and gas-phase PAHs. Approximately 288 m3 of ambient air was drawn over 24 h. The QFF and sorbents were extracted together in an accelerated solvent extraction (ASE) system, and the extract was then nitrogen blown down to 1 ml in an automatic evaporator, and the final extract was analyzed for 32 target PAHs on a gas chromatography/mass spectrometry (GC/MS) system operated in the select-ion-monitoring (SIM) mode. The US Environmental Protection Agency (EPA) reviewed and approved the sampling and analytical protocols. The dataset also has site descriptions, sampling information, and analytical performance. This PAH dataset can be used to explore atmospheric chemistry and sources of PAHs, estimate population exposures to airborne PAHs and the associated health risks, and address environmental health disparities.

Bacterial artificial chromosome clones of viruses comprising the towne cytomegalovirus vaccine.

Bacterial artificial chromosome (BAC) clones have proven invaluable for genetic manipulation of herpesvirus genomes. BAC cloning can also be useful for capturing representative genomes that comprise a viral stock or mixture. The Towne live attenuated cytomegalovirus vaccine was developed in the 1970s by serial passage in cultured fibroblasts. Although its safety, immunogenicity, and efficacy have been evaluated in nearly a thousand human subjects, the vaccine itself has been little studied. Instead, genetic composition and in vitro growth properties have been inferred from studies of laboratory stocks that may not always accurately represent the viruses that comprise the vaccine. Here we describe the use of BAC cloning to define the genotypic and phenotypic properties of viruses from the Towne vaccine. Given the extensive safety history of the Towne vaccine, these BACs provide a logical starting point for the development of next-generation rationally engineered cytomegalovirus vaccines.

Accurate white blood cell differential by Alinity hq: A comparison with flow cytometry and manual differential.

INTRODUCTION: White blood cell (WBC) differential by flow cytometry can report a six-part WBC differential and enumerate blasts. Some modern hematology analyzers are also able to provide a six-part WBC differential (including immature granulocytes). Our goal was to compare the WBC differential obtained by the Abbott Alinity hq hematology analyzer to an 8-color single-tube flow cytometry method and to manual WBC differential. METHODS: Samples from 144 patients were tested with Alinity hq, flow cytometry, and microscopic WBC differential. The WBC count ranged from 1.22 to 359 × 109 /L, and 34 samples were flagged by the analyzer for abnormal WBC morphology. RESULTS: Strong concordance was demonstrated between Alinity hq and flow cytometry for all six components of the differential, with correlation coefficients ranging from 0.86 (basophils) to 1.00 (lymphocytes). Small, clinically insignificant positive difference was observed between Alinity hq and flow cytometry for mature and total neutrophils (2.51% and 1.85%) and eosinophils (0.14%), and small negative difference for immature granulocytes (-0.65%), lymphocytes (-0.61%), and basophils (-0.21%). No bias was detected between the Alinity hq and flow cytometry monocyte counts. Alinity hq and flow cytometry results agreed with the manual differential, apart from small, clinically insignificant differences. Alinity hq nucleated red blood cell concentrations were equivalent with the manual results (r = 0.95, slope = 1.16). The percentage of blasts by flow cytometry demonstrated good correlation and agreement with the manual count (r = 0.99, slope = 1.35). CONCLUSION: Alinity hq has produced accurate six-part WBC differential in this three-way comparison, equivalent to flow cytometry and morphological classification.

A randomised, placebo-controlled phase 3 study to evaluate the efficacy and safety of ASP0113, a DNA-based CMV vaccine, in seropositive allogeneic haematopoietic cell transplant recipients.

BACKGROUND: Cytomegalovirus (CMV) is a complication of allogeneic haematopoietic cell transplantation (allo-HCT). ASP0113, a DNA-based vaccine, contains two plasmids encoding human CMV glycoprotein B and phosphoprotein 65 (pp65). We assessed ASP0113 in CMV-seropositive allo-HCT recipients. METHODS: In this phase 3, randomised, placebo-controlled study, CMV-seropositive allo-HCT recipients were randomly assigned (1:1) via interactive response technology to receive five injections of 1 mL of 5 mg/mL ASP0113 or placebo. The pharmacist and designated staff were unblinded. Masked syringes maintained the blind for patients and study personnel. Efficacy and safety analyses included patients who received ≥1 dose of ASP0113/placebo. The primary efficacy endpoint was the proportion of allo-HCT recipients with composite all-cause mortality and adjudicated CMV end-organ disease (EOD) by 1 year post-transplant. ClinicalTrials.gov: NCT01877655 (not recruiting). FINDINGS: Patients were recruited between Sept 11, 2013 and Sept 21, 2016. Overall, 501 patients received ≥1 dose of ASP0113 (n = 246) or placebo (n = 255). The proportion of patients with composite all-cause mortality and adjudicated CMV EOD by 1 year post-transplant was 35.4% (n = 87) with ASP0113 and 30•2% (n = 77) with placebo (odds ratio 1.27; 95% confidence interval: 0.87 to 1.85; p = 0.205). Incidence of injection site-related treatment-emergent adverse events (TEAEs) was higher with ASP0113 than placebo. Overall incidence and severity of other TEAEs was similar between groups. T-cell response to pp65 increased over time and was greater with placebo than ASP0113 (p = 0.027). INTERPRETATION: ASP0113 did not reduce overall mortality or CMV EOD by 1 year post-transplant. Safety findings were similar between groups. FUNDING: Astellas Pharma Global Development, Inc .

Impacts of Independence Day fireworks on pollution levels of atmospheric polycyclic aromatic hydrocarbons (PAHs) in the U.S.

Fireworks on Independence Day have been identified as a nationwide but short-term source of particulate matter in the U.S. No study has specifically examined their impacts on ambient polycyclic aromatic hydrocarbons (PAHs). Based on data between 1990 and 2019 in the Air Quality System, we identified 76 unique events that had PAH measurements on both July 4th days and control days (within 15 days before and after July 4th). We compared concentrations and diagnostic ratios of 16 priority PAHs between event and control days using Wilcoxon signed-rank tests and multivariable regressions. A local PAH monitoring campaign was conducted at eight sites in Memphis, Tennessee, to obtain a close observation of PAH changes. The national geometric mean (GM) concentrations of summed 16 PAHs (ΣPAHs) were similar between event and control days (48.1 ng/m3 vs. 52.8 ng/m3, p = 0.98). About a quarter of events had elevated PAH concentrations compared with control days. Higher diagnostic ratios were found on event days, suggesting more contributions from fireworks sources. PAHs on July 4th were unlikely to cause acute or chronic health effects. While the local monitoring showed a 15% increase of ΣPAHs on July 4th, the difference was not significant (p = 0.62). Elevated PAH concentrations occurred at sites near fireworks sources and without major traffics, but did not occur at those in remote areas or near major interstate highways. In conclusion, this study finds that Independence Day fireworks have negligible impacts on atmospheric PAHs at the national level, and are unlikely to pose significant health risks. The firework effect is localized within a limited geographic scale, suggesting potential needs for local monitoring and control programs.

Pharmacokinetics and Immunogenicity of ASP0113 in CMV-Seronegative Dialysis Patients and CMV-Seronegative and -Seropositive Healthy Subjects.

Cytomegalovirus (CMV) infection causes significant morbidity and mortality in immunocompromised transplant patients. ASP0113, a first-in-class DNA vaccine containing plasmids encoding CMV phosphoprotein 65 and glycoprotein B (gB), was evaluated in a phase 1b, subject-blinded study in CMV-seropositive (n = 13) and CMV-seronegative (n = 12) healthy and CMV-seronegative dialysis subjects (n = 12) randomized to ASP0113 or placebo. End points included pharmacokinetics, anti-gB antibody levels, phosphoprotein 65-specific T-cell responses measured by ex vivo enzyme-linked immune absorbent spot (ELISpot) assay and 10-day cultured ELISpot and Stat T-cell activation assays, and safety. ASP0113 concentrations peaked at 2-10 and 24-48 hours; the pharmacokinetics were similar across groups. No group demonstrated significant anti-gB antibody responses. T-cell responder rates in the cultured ELISpot assay were 8/12 (66.7%, 95%CI 35% to 90%) and 4/12 (33.3%, 95%CI 10% to 65%) in CMV-seronegative healthy subjects and dialysis patients, respectively, whereas ex vivo ELISpot assay response rates were 4/11 (36.4%, 95%CI 11% to 69%) and 0/12, respectively. Responses peaked at week 27, with lower magnitude observed in CMV-seronegative dialysis patients versus CMV-seronegative healthy subjects. No serious adverse events occurred; the most common adverse event in ASP0113-vaccinated patients was injection-site pain (64.9%). Some CMV-seronegative healthy subjects and dialysis patients had T-cell responses; no humoral responses were detected.

The value of parsing as feature generation for gene mention recognition.

We measured the extent to which information surrounding a base noun phrase reflects the presence of a gene name, and evaluated seven different parsers in their ability to provide information for that purpose. Using the GENETAG corpus as a gold standard, we performed machine learning to recognize from its context when a base noun phrase contained a gene name. Starting with the best lexical features, we assessed the gain of adding dependency or dependency-like relations from a full sentence parse. Features derived from parsers improved performance in this partial gene mention recognition task by a small but statistically significant amount. There were virtually no differences between parsers in these experiments.

Evaluation of a plasmid DNA-based anthrax vaccine in rabbits, nonhuman primates and healthy adults.

VCL-AB01, a cationic lipid-formulated plasmid DNA (pDNA)-based vaccine that contains genes encoding genetically detoxified Bacillus anthracis protective antigen (PA) and lethal factor (LF), was assessed in a Phase 1, dose-escalating clinical trial in healthy adults for safety and immunogenicity, and in nonhuman primates for immunogenicity and efficacy against challenge with a lethal dose of B. anthracis spores. Healthy 18-45 year old subjects were randomly assigned to receive either the investigational vaccine containing 0.2 mg, 0.6 mg, or 2 mg of total pDNA per dose, or saline placebo, administered at 0, 1 and 2 months. The 0.2 mg and 0.6 mg dose levels were generally well tolerated; however, dose-limiting reactogenicity was observed among subjects given the first 2 mg dose and the remaining two injections in the 2 mg group were reduced to 0.6 mg. Dose-related increases in seroconversion frequencies were observed. Overall, 10%, 33.3% and 80% of subjects in the 0.2, 0.6 and 2 mg groups, respectively, developed antibodies to PA and/or LF as measured by ELISA; however, antibodies with toxin neutralizing activity (TNA) were detected in only one subject. In monkeys that received a 0.6 mg dose three times at 2 week intervals, low levels of antibodies were detected by ELISA but not by the TNA assay in all animals just prior to challenge. Despite the absence of TNA, 75% animals survived the lethal challenge. In summary, VCL-AB01 was generally well tolerated in humans at a dose that provided immunity in monkeys despite the lack of robust TNA titers in either species.

Mechanical and Finite Element Analysis of an Innovative Orthopedic Implant Designed to Increase the Weight Carrying Ability of the Femur and Reduce Frictional Forces on an Amputee's Stump.

This study was designed to test the hypothesis that: "A properly designed implant that harnesses the principle of the incompressibility of fluids can improve the weight carrying ability of an amputee's residual femur and reduce the frictional forces at the stump external socket interface." The hypothesis was tested both mechanically on an Amputee Simulation Device (ASD) and through Finite Element Analysis (FEA) modeling software. With the implant attached to the femur, the FEA and ASD demonstrated that the femur carried 90% and 93% respectively of the force of walking. Without the implant, the FEA model and ASD femur carried only 35% and 77%, respectively, of the force of walking. Statistical calculations reveal three (3) degrees of separation (99% probability of non-random significant difference) between with and without implant data points. FEA modeling demonstrates that the normal contact forces and shear forces are pushed the distal weight-bearing area of the amputee stump, relieving the lateral stump of frictional forces. The ASD mechanical and FEA modeling data validate each other with both systems supporting the hypotheses with confidence intervals of three degrees of separation between with implant and without implant models.

D-dimer assay to exclude pulmonary embolism in high-risk oncologic population: correlation with CT pulmonary angiography in an urgent care setting.

PURPOSE: To prospectively evaluate (a) the diagnostic performance of D-dimer assay for pulmonary embolism (PE) in an oncologic population by using computed tomographic (CT) pulmonary angiography as the reference standard, (b) the association between PE location and assay sensitivity, and (c) the association between assay results and clinical factors that raise suspicion of PE. MATERIALS AND METHODS: This HIPAA-compliant study had institutional review board approval; informed consent was obtained. Five hundred thirty-one consecutive patients were clinically suspected of having PE; 201 were enrolled (72 men, 129 women; median age, 61 years) and underwent CT pulmonary angiography and D-dimer assay. Relevant clinical history, symptoms, and signs were recorded. CT images were interpreted, and the location of emboli was recorded. The negative predictive value (NPV), positive predictive value (PPV), sensitivity, specificity, and diagnostic likelihood ratios of the D-dimer assay results were calculated. RESULTS: Forty-three patients (21%) had pulmonary emboli at CT. D-Dimer results were positive in 171 patents (85%). The NPV and sensitivity were 97% and 98%, respectively. The specificity and PPV were 18% and 25%, respectively. No association was shown between clinical history, symptoms, or signs and NPV, PPV, sensitivity, or specificity or between location of PE and sensitivity. CONCLUSION: D-Dimer results have high NPV and sensitivity for PE in oncologic patients and, if negative, can be used to exclude PE in this population. Combining the assay with clinical symptoms and signs did not substantially change NPV, PPV, sensitivity, or specificity.

A brief history of medicine's Hippocratic Oath, or how times have changed.

Medicine has experienced many changes over the last three thousand years and surprisingly, the good and the bad of these changes can be found in the evolution of the wording of the Hippocratic Oath. This commentary reveals why the original Oath became a part of modern medicine's rite of passage and how society is now changing the very reason that the Hippocratic Oath was brought into the world of medical ethics. By examining the modern language of the Oath, it is possible to understand how these words have diluted its meaning and intent. The long-term consequences of these changes cannot be foreseen, but history has shown what can happen without a strong oath to guide the practitioner.

An otolaryngologist's experience with in-flight commercial airline medical emergencies: three case reports and literature review.

Managing a medical emergency onboard a commercial airline is an uncommon but real possibility for those physicians who fly. Understanding your potential role, management options, medical supplies and help that is available to you is important.