57 results on '"Stevens LJ"'
Search Results
2. Essential fatty acid metabolism in boys with attention-deficit hyperactivity disorder
- Author
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Stevens, LJ, primary, Zentall, SS, additional, Deck, JL, additional, Abate, ML, additional, Watkins, BA, additional, Lipp, SR, additional, and Burgess, JR, additional
- Published
- 1995
- Full Text
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3. An oral non-covalent non-peptidic inhibitor of SARS-CoV-2 Mpro ameliorates viral replication and pathogenesis in vivo.
- Author
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Zhou NE, Tang S, Bian X, Parai MK, Krieger IV, Flores A, Jaiswal PK, Bam R, Wood JL, Shi Z, Stevens LJ, Scobey T, Diefenbacher MV, Moreira FR, Baric TJ, Acharya A, Shin J, Rathi MM, Wolff KC, Riva L, Bakowski MA, McNamara CW, Catanzaro NJ, Graham RL, Schultz DC, Cherry S, Kawaoka Y, Halfmann PJ, Baric RS, Denison MR, Sheahan TP, and Sacchettini JC
- Subjects
- Animals, Humans, Mice, Cricetinae, Coronavirus 3C Proteases antagonists & inhibitors, Coronavirus 3C Proteases metabolism, Chlorocebus aethiops, Administration, Oral, Vero Cells, Mesocricetus, Cell Line, Protease Inhibitors pharmacology, Female, Disease Models, Animal, Virus Replication drug effects, SARS-CoV-2 drug effects, SARS-CoV-2 physiology, Antiviral Agents pharmacology, COVID-19 virology, COVID-19 Drug Treatment
- Abstract
Safe, effective, and low-cost oral antiviral therapies are needed to treat those at high risk for developing severe COVID-19. To that end, we performed a high-throughput screen to identify non-peptidic, non-covalent inhibitors of the SARS-CoV-2 main protease (Mpro), an essential enzyme in viral replication. NZ-804 was developed from a screening hit through iterative rounds of structure-guided medicinal chemistry. NZ-804 potently inhibits SARS-CoV-2 Mpro (0.009 μM IC
50 ) as well as SARS-CoV-2 replication in human lung cell lines (0.008 μM EC50 ) and primary human airway epithelial cell cultures. Antiviral activity is maintained against distantly related sarbecoviruses and endemic human CoV OC43. In SARS-CoV-2 mouse and hamster disease models, NZ-804 therapy given once or twice daily significantly diminished SARS-CoV-2 replication and pathogenesis. NZ-804 synthesis is low cost and uncomplicated, simplifying global production and access. These data support the exploration of NZ-804 as a therapy for COVID-19 and future emerging sarbecovirus infections., Competing Interests: Declaration of interests J.C.S., S.T., X.B., I.V.K., J.L.W., N.E.Z., M.K.P., A.A., P.K.J., R.B., A.F., and Z.S. are listed as inventors on a patent for NZ-804. R.S.B. is a member of the advisory boards of VaxArt and Invivyd and has collaborations with Takeda, Pfizer, Moderna, Ridgeback Biosciences, Gilead, and Eli Lily. Y.K. has received unrelated funding support from Daiichi Sankyo Pharmaceutical, Toyama Chemical, Tauns Laboratories, Inc., Shionogi & Co., Ltd., Otsuka Pharmaceutical, KM Biologics, Kyoritsu Seiyaku, Shinya Corporation, and Fuji Rebio., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2024
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4. Highly demarcated structural alterations in the brain and impaired social incentive learning in Tbx1 heterozygous mice.
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Hiramoto T, Sumiyoshi A, Kato R, Yamauchi T, Takano T, Kang G, Esparza M, Matsumura B, Stevens LJ, Hiroi YJ, Tanifuji T, Ryoke R, Nonaka H, Machida A, Nomoto K, Mogi K, Kikusui T, Kawashima R, and Hiroi N
- Abstract
Copy number variants (CNVs) are robustly associated with psychiatric disorders and changes in brain structures. However, because CNVs contain many genes, the precise gene-phenotype relationship remains unclear. Although various volumetric alterations in the brains of 22q11.2 CNV carriers have been identified in humans and mouse models, it is unknown how each gene encoded in the 22q11.2 region contributes to structural alterations, associated mental illnesses, and their dimensions. Our previous studies identified Tbx1, a T-box family transcription factor encoded in the 22q11.2 CNV, as a driver gene for social interaction and communication, spatial and working memory, and cognitive flexibility. However, it remains unclear how TBX1 impacts the volumes of various brain regions and their functionally linked behavioral dimensions. In this study, we used volumetric magnetic resonance imaging analysis to comprehensively evaluate brain region volumes and behavioral alterations relevant to affected structures in congenic Tbx1 heterozygous mice. Our data showed that the volumes of the anterior and posterior portions of the amygdaloid complex and its surrounding cortical regions were most robustly reduced in Tbx1 heterozygous mice. In an amygdala-dependent task, Tbx1 heterozygous mice were impaired in their ability to learn the incentive value of a social partner. The volumes of the primary and secondary auditory cortexes were increased, and acoustic, but not non-acoustic, sensorimotor gating was impaired in Tbx1 heterozygous mice. Our findings identify the brain's regional volume alterations and their relevant behavioral dimensions associated with Tbx1 heterozygosity., (© 2024. The Author(s).)
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- 2024
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5. Ex vivo gut-hepato-biliary organ perfusion model to characterize oral absorption, gut-wall metabolism, pre-systemic hepatic metabolism and biliary excretion; application to midazolam.
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Stevens LJ, van de Steeg E, Doppenberg JB, Alwayn IPJ, Knibbe CAJ, and Dubbeld J
- Abstract
To date, characterization of the first-pass effect of orally administered drugs consisting of local intestinal absorption and metabolism, portal vein transport and hepatobiliary processes remains challenging. Aim of this study was to explore the applicability of a porcine ex-vivo perfusion model to study oral absorption, gut-hepatobiliary metabolism and biliary excretion of midazolam. Slaughterhouse procured porcine en bloc organs (n = 4), were perfused via the aorta and portal vein. After 120 min of perfusion, midazolam, atenolol, antipyrine and FD4 were dosed via the duodenum and samples were taken from the systemic- and portal vein perfusate, intestinal faecal effluent and bile to determine drug and metabolite concentrations. Stable arterial and portal vein flow was obtained and viability of the perfused organs was confirmed. After intraduodenal administration, midazolam was rapidly detected in the portal vein together with 1-OH midazolam (E
G-pv of 0.16±0.1) resulting from gut wall metabolism through oxidation. In the intestinal faecal effluent, 1-OH midazolam and 1-OH midazolam glucuronide (EG-intestine 0.051±0.03) was observed resulting from local gut glucuronidation. Biliary elimination of midazolam (0.04±0.01 %) and its glucuronide (0.01±0.01 %) only minimally contributed to the enterohepatic circulation. More extensive hepatic metabolism (FH 0.35±0.07) over intestinal metabolism (FG 0.78±0.11) was shown, resulting in oral bioavailability of 0.27±0.05. Ex vivo perfusion demonstrated to be a novel approach to characterize pre-systemic extraction of midazolam by measuring intestinal as well as hepatic extraction. The model can generate valuable insights into the absorption and metabolism of new drugs., Competing Interests: Declaration of competing interest All contributors report no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)- Published
- 2024
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6. Quantifying Offense and Defense Workloads in Professional Rugby Union.
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Stevens LJ, Hopkins WG, Chittenden JA, Koper BZ, and Smith TB
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- Humans, Workload, Rugby, Geographic Information Systems, Football, Athletic Performance, Running
- Abstract
Purpose: Rugby union is a contact team sport demanding high levels of physical capacity, and understanding the match workloads can be useful to inform training. In this study, the factors influencing locomotion and contact workloads for offensive and defensive ball-in-play periods are quantified., Methods: Locomotion and contact metrics were collected from global positioning system units and videos for 31 professional players of a Super Rugby team across 14 games in the 2021 season. Data were analyzed with a generalized mixed-model procedure that included effects for type of play, playing position, match outcome, and ball-in-play time. Magnitudes were assessed with standardization, and evidence for substantial magnitudes was derived from sampling uncertainty., Results: When offense was compared to defense, most metrics showed decisively substantial increases (small to moderate) for forwards and backs. There was decisive evidence that locomotion metrics were substantially lower (large differences) and contact metrics were higher (very large differences) when comparing forwards to backs on offense and defense. When winning was compared to losing, there was good evidence that forwards experienced small increases in overall workload on defense, and backs experienced a small increase in high-speed running and a moderate decrease in contacts on offense. Match-to-match changes associated with ball-in-play time, attributed to fatigue, were decisive (moderate to very large) across most metrics for forwards and backs in offense and defense., Conclusions: The increased locomotion and contact workloads in offensive periods and the differing physical requirements between positions and match outcomes for both types of play are novel findings that should aid practitioners in designing effective training.
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- 2024
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7. Evaluation of in vitro antiviral activity of SARS-CoV-2 M pro inhibitor pomotrelvir and cross-resistance to nirmatrelvir resistance substitutions.
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Tong X, Keung W, Arnold LD, Stevens LJ, Pruijssers AJ, Kook S, Lopatin U, Denison M, and Kwong AD
- Subjects
- Humans, SARS-CoV-2, Pandemics, Antiviral Agents pharmacology, Protease Inhibitors, COVID-19, Coronavirus 229E, Human
- Abstract
The unprecedented scale of the COVID-19 pandemic and the rapid evolution of SARS-CoV-2 variants underscore the need for broadly active inhibitors with a high barrier to resistance. The coronavirus main protease (M
pro ) is an essential cysteine protease required for viral polyprotein processing and is highly conserved across human coronaviruses. Pomotrelvir is a novel Mpro inhibitor that has recently completed a phase 2 clinical trial. In this report, we demonstrated that pomotrelvir is a potent competitive inhibitor of SARS-CoV-2 Mpro with high selectivity against human proteases. In the enzyme assay, pomotrelvir is also active against Mpro proteins derived from human coronaviruses CoV-229E, CoV-OC43, CoV-HKU1, CoV-NL63, MERS, and SARS-CoV. In cell-based SARS-CoV-2 replicon and SARS-CoV-2 infection assays, pomotrelvir has shown potent inhibitory activity and is broadly active against SARS-CoV-2 clinical isolates including Omicron variants. Many resistance substitutions of the Mpro inhibitor nirmatrelvir confer cross-resistance to pomotrelvir, consistent with the finding from our enzymatic analysis that pomotrelvir and nirmatrelvir compete for the same binding site. In a SARS-CoV-2 infection assay, pomotrelvir is additive when combined with remdesivir or molnupiravir, two nucleoside analogs targeting viral RNA synthesis. In conclusion, our results from the in vitro characterization of pomotrelvir antiviral activity support its further clinical development as an alternative COVID-19 therapeutic option., Competing Interests: All employees of Pardes Biosciences were granted stock options in the company.- Published
- 2023
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8. Structural alterations in the amygdala and impaired social incentive learning in a mouse model of a genetic variant associated with neurodevelopmental disorders.
- Author
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Hiramoto T, Sumiyoshi A, Kato R, Yamauchi T, Kang G, Matsumura B, Stevens LJ, Ryoke R, Nonaka H, Machida A, Nomoto K, Mogi K, Hiroi YJ, Kikusui T, Kawashima R, and Hiroi N
- Abstract
Copy number variants (CNVs) are robustly associated with psychiatric disorders and their dimensions and changes in brain structures and behavior. However, as CNVs contain many genes, the precise gene-phenotype relationship remains unclear. Although various volumetric alterations in the brains of 22q11.2 CNV carriers have been identified in humans and mouse models, it is unknown how the genes in the 22q11.2 region individually contribute to structural alterations and associated mental illnesses and their dimensions. Our previous studies have identified Tbx1, a T-box family transcription factor encoded in 22q11.2 CNV, as a driver gene for social interaction and communication, spatial and working memory, and cognitive flexibility. However, it remains unclear how TBX1 impacts the volumes of various brain regions and their functionally linked behavioral dimensions. In this study, we used volumetric magnetic resonance imaging analysis to comprehensively evaluate brain region volumes in congenic Tbx1 heterozygous mice. Our data show that the volumes of anterior and posterior portions of the amygdaloid complex and its surrounding cortical regions were reduced in Tbx1 heterozygous mice. Moreover, we examined the behavioral consequences of an altered volume of the amygdala. Tbx1 heterozygous mice were impaired for their ability to detect the incentive value of a social partner in a task that depends on the amygdala. Our findings identify the structural basis for a specific social dimension associated with loss-of-function variants of TBX1 and 22q11.2 CNV.
- Published
- 2023
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9. Novel Explanted Human Liver Model to Assess Hepatic Extraction, Biliary Excretion and Transporter Function.
- Author
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Stevens LJ, Dubbeld J, Doppenberg JB, van Hoek B, Menke AL, Donkers JM, Alsharaa A, de Vries A, Vaes WHJ, Knibbe CAJ, van de Steeg E, and Alwayn IPJ
- Subjects
- Humans, Rosuvastatin Calcium pharmacokinetics, Hepatobiliary Elimination, ATP Binding Cassette Transporter, Subfamily G, Member 2 metabolism, Neoplasm Proteins metabolism, Membrane Transport Proteins metabolism, Liver metabolism, Liver Cirrhosis, Digoxin pharmacokinetics, Drug Interactions, Furosemide pharmacokinetics, Metformin pharmacokinetics
- Abstract
Realistic models predicting hepatobiliary processes in health and disease are lacking. We therefore aimed to develop a physiologically relevant human liver model consisting of normothermic machine perfusion (NMP) of explanted diseased human livers that can assess hepatic extraction, clearance, biliary excretion, and drug-drug interaction (DDI). Eleven livers were included in the study, seven with a cirrhotic and four with a noncirrhotic disease background. After explantation of the diseased liver, NMP was initiated. After 120 minutes of perfusion, a drug cocktail (rosuvastatin, digoxin, metformin, and furosemide; OATP1B1/1B3, P-gp, BCRP, and OCT1 model compounds) was administered to the portal vein and 120 minutes later, a second bolus of the drug cocktail was co-administered with perpetrator drugs to study relevant DDIs. The explanted livers showed good viability and functionality during 360 minutes of NMP. Hepatic extraction ratios close to in vivo reported values were measured. Hepatic clearance of rosuvastatin and digoxin showed to be the most affected by cirrhosis with an increase in maximum plasma concentration (C
max ) of 11.50 and 2.89 times, respectively, compared with noncirrhotic livers. No major differences were observed for metformin and furosemide. Interaction of rosuvastatin or digoxin with perpetrator drugs were more pronounced in noncirrhotic livers compared with cirrhotic livers. Our results demonstrated that NMP of human diseased explanted livers is an excellent model to assess hepatic extraction, clearance, biliary excretion, and DDI. Gaining insight into pharmacokinetic profiles of OATP1B1/1B3, P-gp, BCRP, and OCT1 model compounds is a first step toward studying transporter functions in diseased livers., (© 2023 The Authors. Clinical Pharmacology & Therapeutics published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)- Published
- 2023
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10. Neutralizing COVID-19 Convalescent Plasma in Adults Hospitalized With COVID-19: A Blinded, Randomized, Placebo-Controlled Trial.
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Self WH, Wheeler AP, Stewart TG, Schrager H, Mallada J, Thomas CB, Cataldo VD, O'Neal HR Jr, Shapiro NI, Higgins C, Ginde AA, Chauhan L, Johnson NJ, Henning DJ, Jaiswal SJ, Mammen MJ, Harris ES, Pannu SR, Laguio-Vila M, El Atrouni W, de Wit M, Hoda D, Cohn CS, McWilliams C, Shanholtz C, Jones AE, Raval JS, Mucha S, Ipe TS, Qiao X, Schrantz SJ, Shenoy A, Fremont RD, Brady EJ, Carnahan RH, Chappell JD, Crowe JE Jr, Denison MR, Gilchuk P, Stevens LJ, Sutton RE, Thomsen I, Yoder SM, Bistran-Hall AJ, Casey JD, Lindsell CJ, Wang L, Pulley JM, Rhoads JP, Bernard GR, and Rice TW
- Subjects
- Adult, Humans, SARS-CoV-2, Antibodies, Viral, Hospitalization, Treatment Outcome, COVID-19 Serotherapy, COVID-19 therapy
- Abstract
Background: Convalescent plasma has been one of the most common treatments for COVID-19, but most clinical trial data to date have not supported its efficacy., Research Question: Is rigorously selected COVID-19 convalescent plasma with neutralizing anti-SARS-CoV-2 antibodies an efficacious treatment for adults hospitalized with COVID-19?, Study Design and Methods: This was a multicenter, blinded, placebo-controlled randomized clinical trial among adults hospitalized with SARS-CoV-2 infection and acute respiratory symptoms for < 14 days. Enrolled patients were randomly assigned to receive one unit of COVID-19 convalescent plasma (n = 487) or placebo (n = 473). The primary outcome was clinical status (disease severity) 14 days following study infusion measured with a seven-category ordinal scale ranging from discharged from the hospital with resumption of normal activities (lowest score) to death (highest score). The primary outcome was analyzed with a multivariable ordinal regression model, with an adjusted odds ratio (aOR) < 1.0 indicating more favorable outcomes with convalescent plasma than with placebo. In secondary analyses, trial participants were stratified according to the presence of endogenous anti-SARS-CoV-2 antibodies ("serostatus") at randomization. The trial included 13 secondary efficacy outcomes, including 28-day mortality., Results: Among 974 randomized patients, 960 were included in the primary analysis. Clinical status on the ordinal outcome scale at 14 days did not differ between the convalescent plasma and placebo groups in the overall population (aOR, 1.04; one-seventh support interval [1/7 SI], 0.82-1.33), in patients without endogenous antibodies (aOR, 1.15; 1/7 SI, 0.74-1.80), or in patients with endogenous antibodies (aOR, 0.96; 1/7 SI, 0.72-1.30). None of the 13 secondary efficacy outcomes were different between groups. At 28 days, 89 of 482 (18.5%) patients in the convalescent plasma group and 80 of 465 (17.2%) patients in the placebo group had died (aOR, 1.04; 1/7 SI, 0.69-1.58)., Interpretation: Among adults hospitalized with COVID-19, including those seronegative for anti-SARS-CoV-2 antibodies, treatment with convalescent plasma did not improve clinical outcomes., Clinical Trial Registration: ClinicalTrials.gov; No.: NCT04362176; URL: www., Clinicaltrials: gov., (Copyright © 2022 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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11. Enhanced neurotrauma services: physician input into traumatic brain injury care.
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Harris CM, Okamura K, Stevens LJ, and Jenkins DR
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- Humans, Aged, Retrospective Studies, Length of Stay, Hospitalization, Brain Injuries, Traumatic therapy, Surgeons
- Abstract
Elderly trauma victims whose care is shared between surgeons and physicians have improved clinical outcomes and shorter hospital lengths of stay (LOS). To test whether a similar benefit can be gained for patients suffering traumatic brain injury (TBI), a quality improvement project (QIP) was run in which a neurologist was enrolled into the pre-existing neurotrauma team. Mortality rates, LOS and rates of readmission within 30 days of discharge were compared between two cohorts of TBI patients: 80 admittedly prior to the QIP and 80 admitted during the QIP. The two cohorts were well matched for age, gender, mechanism of injury, Glasgow coma score and types of injury. The QIP was not associated with a reduction in mortality but was associated with a significant reduction in mean LOS (from 25.7 days to 17.5 days; p=0.04) and a reduction in readmissions (from seven to zero patients; p=0.01)., (© Royal College of Physicians 2022. All rights reserved.)
- Published
- 2022
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12. Mutations in the SARS-CoV-2 RNA-dependent RNA polymerase confer resistance to remdesivir by distinct mechanisms.
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Stevens LJ, Pruijssers AJ, Lee HW, Gordon CJ, Tchesnokov EP, Gribble J, George AS, Hughes TM, Lu X, Li J, Perry JK, Porter DP, Cihlar T, Sheahan TP, Baric RS, Götte M, and Denison MR
- Subjects
- Adenosine Monophosphate analogs & derivatives, Alanine analogs & derivatives, Animals, Humans, Mice, Mutation genetics, RNA, Viral genetics, Antiviral Agents pharmacology, Drug Resistance, Viral genetics, RNA-Dependent RNA Polymerase genetics, SARS-CoV-2 drug effects, SARS-CoV-2 genetics, COVID-19 Drug Treatment
- Abstract
The nucleoside analog remdesivir (RDV) is a Food and Drug Administration-approved antiviral for treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Thus, it is critical to understand factors that promote or prevent RDV resistance. We passaged SARS-CoV-2 in the presence of increasing concentrations of GS-441524, the parent nucleoside of RDV. After 13 passages, we isolated three viral lineages with phenotypic resistance as defined by increases in half-maximal effective concentration from 2.7- to 10.4-fold. Sequence analysis identified nonsynonymous mutations in nonstructural protein 12 RNA-dependent RNA polymerase ( nsp12 -RdRp): V166A, N198S, S759A, V792I, and C799F/R. Two lineages encoded the S759A substitution at the RdRp Ser
759 -Asp-Asp active motif. In one lineage, the V792I substitution emerged first and then combined with S759A. Introduction of S759A and V792I substitutions at homologous nsp12 positions in murine hepatitis virus demonstrated transferability across betacoronaviruses; introduction of these substitutions resulted in up to 38-fold RDV resistance and a replication defect. Biochemical analysis of SARS-CoV-2 RdRp encoding S759A demonstrated a roughly 10-fold decreased preference for RDV-triphosphate (RDV-TP) as a substrate, whereas nsp12 -V792I diminished the uridine triphosphate concentration needed to overcome template-dependent inhibition associated with RDV. The in vitro-selected substitutions identified in this study were rare or not detected in the greater than 6 million publicly available nsp12 -RdRp consensus sequences in the absence of RDV selection. The results define genetic and biochemical pathways to RDV resistance and emphasize the need for additional studies to define the potential for emergence of these or other RDV resistance mutations in clinical settings.- Published
- 2022
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13. Standardized two-step testing of antibody activity in COVID-19 convalescent plasma.
- Author
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Gilchuk P, Thomsen I, Yoder S, Brady E, Chappell JD, Stevens LJ, Denison MR, Sutton RE, Chen RE, VanBlargan LA, Suryadevara N, Zost SJ, Schmitz J, Pulley JM, Diamond MS, Rhoads JP, Bernard GR, Self WH, Rice TW, Wheeler AP, Crowe JE Jr, and Carnahan RH
- Abstract
The COVID-19 pandemic revealed an urgent need for rapid profiling of neutralizing antibody responses and development of antibody therapeutics. The current Food and Drug Administration-approved serological tests do not measure antibody-mediated viral neutralization, and there is a need for standardized quantitative neutralization assays. We report a high-throughput two-step profiling approach for identifying neutralizing convalescent plasma. Screening and downselection for serum antibody binding to the receptor-binding domain are followed by quantitative neutralization testing using a chimeric vesicular stomatitis virus expressing spike protein of SARS-CoV-2 in a real-time cell analysis assay. This approach enables a predictive screening process for identifying plasma units that neutralize SARS-CoV-2. To calibrate antibody neutralizing activity in serum from convalescent plasma donors, we introduce a neutralizing antibody standard reagent composed of two human antibodies that neutralize SARS-CoV strains, including SARS-CoV-2 variants of concern. Our results provide a framework for establishing a standardized assessment of antibody-based interventions against COVID-19., Competing Interests: I.T. reports grants from NIH/NIAID, during the conduct of the study, and has served as a consultant for Nashville Biosciences and Horizon Therapeutics. J. D. C., L.J.S., and M.R.D. report grants from NIH/NCATS, during the conduct of the study. T.W.R. reports grants from NIH/NCATS, during the conduct of the study; personal fees from Cumberland Pharmaceuticals, Inc, personal fees from Sanofi Pharma, and personal fees from Cytovale, outside the submitted work. T.G.S. reports grants from NIH, during the conduct of the study. W.H.S. reports grants from NCATS of the NIH, during the conduct of the study. M.S.D. is a consultant for Inbios, Vir Biotechnology, Fortress Biotech, and Carnival Corporation and on the Scientific Advisory Boards of Moderna and Immunome. The Diamond laboratory has received funding support in sponsored research agreements from Moderna, Vir Biotechnology, and Emergent BioSolutions. J.E.C. has served as a consultant for Luna Biologics, is a member of the Scientific Advisory Board of Meissa Vaccines and is Founder of IDBiologics. The Crowe laboratory at Vanderbilt University Medical Center has received sponsored research agreements from Takeda Vaccines, IDBiologics, and AstraZeneca and grants from NIH, and DARPA during the conduct of the study. Vanderbilt University has applied for patents related to antibodies described in this paper. All other authors declare no competing interests., (© 2021 The Authors.)
- Published
- 2022
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14. Stabilized coronavirus spike stem elicits a broadly protective antibody.
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Hsieh CL, Werner AP, Leist SR, Stevens LJ, Falconer E, Goldsmith JA, Chou CW, Abiona OM, West A, Westendorf K, Muthuraman K, Fritch EJ, Dinnon KH 3rd, Schäfer A, Denison MR, Chappell JD, Baric RS, Graham BS, Corbett KS, and McLellan JS
- Subjects
- Animals, Cell Line, Coronavirus Infections immunology, Coronavirus Infections prevention & control, Cross Reactions, Drug Design, Epitope Mapping, Female, Immunoglobulin G immunology, Male, Mice, Mice, Inbred BALB C, SARS-CoV-2 immunology, Spike Glycoprotein, Coronavirus chemistry, Viral Vaccines immunology, Antibodies, Viral immunology, Middle East Respiratory Syndrome Coronavirus immunology, Spike Glycoprotein, Coronavirus immunology
- Abstract
Current coronavirus (CoV) vaccines primarily target immunodominant epitopes in the S1 subunit, which are poorly conserved and susceptible to escape mutations, thus threatening vaccine efficacy. Here, we use structure-guided protein engineering to remove the S1 subunit from the Middle East respiratory syndrome (MERS)-CoV spike (S) glycoprotein and develop stabilized stem (SS) antigens. Vaccination with MERS SS elicits cross-reactive β-CoV antibody responses and protects mice against lethal MERS-CoV challenge. High-throughput screening of antibody-secreting cells from MERS SS-immunized mice led to the discovery of a panel of cross-reactive monoclonal antibodies. Among them, antibody IgG22 binds with high affinity to both MERS-CoV and severe acute respiratory syndrome (SARS)-CoV-2 S proteins, and a combination of electron microscopy and crystal structures localizes the epitope to a conserved coiled-coil region in the S2 subunit. Passive transfer of IgG22 protects mice against both MERS-CoV and SARS-CoV-2 challenge. Collectively, these results provide a proof of principle for cross-reactive CoV antibodies and inform the development of pan-CoV vaccines and therapeutic antibodies., Competing Interests: Declaration of interests C-L.H. and J.S.M. are inventors on U.S. patent application no. 63/188,813 (“Stabilized S2 Beta-coronavirus Antigens”). This research was, in part, funded by the U.S. Government. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the U.S. Government. S.R.L., K.H.D., and R.S.B. have a pending patent for recombinant SARS-CoV-2 MA10 used in this study., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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15. Durability of mRNA-1273 vaccine-induced antibodies against SARS-CoV-2 variants.
- Author
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Pegu A, O'Connell SE, Schmidt SD, O'Dell S, Talana CA, Lai L, Albert J, Anderson E, Bennett H, Corbett KS, Flach B, Jackson L, Leav B, Ledgerwood JE, Luke CJ, Makowski M, Nason MC, Roberts PC, Roederer M, Rebolledo PA, Rostad CA, Rouphael NG, Shi W, Wang L, Widge AT, Yang ES, Beigel JH, Graham BS, Mascola JR, Suthar MS, McDermott AB, Doria-Rose NA, Arega J, Beigel JH, Buchanan W, Elsafy M, Hoang B, Lampley R, Kolhekar A, Koo H, Luke C, Makhene M, Nayak S, Pikaart-Tautges R, Roberts PC, Russell J, Sindall E, Albert J, Kunwar P, Makowski M, Anderson EJ, Bechnak A, Bower M, Camacho-Gonzalez AF, Collins M, Drobeniuc A, Edara VV, Edupuganti S, Floyd K, Gibson T, Ackerley CMG, Johnson B, Kamidani S, Kao C, Kelley C, Lai L, Macenczak H, McCullough MP, Peters E, Phadke VK, Rebolledo PA, Rostad CA, Rouphael N, Scherer E, Sherman A, Stephens K, Suthar MS, Teherani M, Traenkner J, Winston J, Yildirim I, Barr L, Benoit J, Carste B, Choe J, Dunstan M, Erolin R, Ffitch J, Fields C, Jackson LA, Kiniry E, Lasicka S, Lee S, Nguyen M, Pimienta S, Suyehira J, Witte M, Bennett H, Altaras NE, Carfi A, Hurley M, Leav B, Pajon R, Sun W, Zaks T, Coler RN, Larsen SE, Neuzil KM, Lindesmith LC, Martinez DR, Munt J, Mallory M, Edwards C, Baric RS, Berkowitz NM, Boritz EA, Carlton K, Corbett KS, Costner P, Creanga A, Doria-Rose NA, Douek DC, Flach B, Gaudinski M, Gordon I, Graham BS, Holman L, Ledgerwood JE, Leung K, Lin BC, Louder MK, Mascola JR, McDermott AB, Morabito KM, Novik L, O'Connell S, O'Dell S, Padilla M, Pegu A, Schmidt SD, Shi W, Swanson PA 2nd, Talana CA, Wang L, Widge AT, Yang ES, Zhang Y, Chappell JD, Denison MR, Hughes T, Lu X, Pruijssers AJ, Stevens LJ, Posavad CM, Gale M Jr, Menachery V, and Shi PY
- Subjects
- 2019-nCoV Vaccine mRNA-1273, Adolescent, Adult, Aged, Antibodies, Neutralizing immunology, Antibodies, Viral immunology, COVID-19 prevention & control, COVID-19 Vaccines administration & dosage, Cross Reactions, Humans, Immune Evasion, Immunization, Secondary, Immunogenicity, Vaccine, Middle Aged, Time Factors, Young Adult, Antibodies, Neutralizing blood, Antibodies, Viral blood, COVID-19 Vaccines immunology, SARS-CoV-2 immunology
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutations may diminish vaccine-induced protective immune responses, particularly as antibody titers wane over time. Here, we assess the effect of SARS-CoV-2 variants B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.429 (Epsilon), B.1.526 (Iota), and B.1.617.2 (Delta) on binding, neutralizing, and angiotensin-converting enzyme 2 (ACE2)–competing antibodies elicited by the messenger RNA (mRNA) vaccine mRNA-1273 over 7 months. Cross-reactive neutralizing responses were rare after a single dose. At the peak of response to the second vaccine dose, all individuals had responses to all variants. Binding and functional antibodies against variants persisted in most subjects, albeit at low levels, for 6 months after the primary series of the mRNA-1273 vaccine. Across all assays, B.1.351 had the lowest antibody recognition. These data complement ongoing studies to inform the potential need for additional boost vaccinations.
- Published
- 2021
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16. Evaluation of Normothermic Machine Perfusion of Porcine Livers as a Novel Preclinical Model to Predict Biliary Clearance and Transporter-Mediated Drug-Drug Interactions Using Statins.
- Author
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Stevens LJ, Zhu AZX, Chothe PP, Chowdhury SK, Donkers JM, Vaes WHJ, Knibbe CAJ, Alwayn IPJ, and van de Steeg E
- Subjects
- Animals, Drug Evaluation, Preclinical instrumentation, Drug Evaluation, Preclinical methods, Equipment Design, In Vitro Techniques instrumentation, Metabolic Clearance Rate, Perfusion instrumentation, Perfusion methods, Reproducibility of Results, Swine, Drug Interactions, Hepatobiliary Elimination physiology, Hydroxymethylglutaryl-CoA Reductase Inhibitors pharmacokinetics, Inactivation, Metabolic physiology, Liver metabolism, Liver pathology
- Abstract
There is a lack of translational preclinical models that can predict hepatic handling of drugs. In this study, we aimed to evaluate the applicability of normothermic machine perfusion (NMP) of porcine livers as a novel ex vivo model to predict hepatic clearance, biliary excretion, and plasma exposure of drugs. For this evaluation, we dosed atorvastatin, pitavastatin, and rosuvastatin as model drugs to porcine livers and studied the effect of common drug-drug interactions (DDIs) on these processes. After 120 minutes of perfusion, 0.104 mg atorvastatin ( n = 3), 0.140 mg pitavastatin ( n = 5), or 1.4 mg rosuvastatin ( n = 4) was administered to the portal vein, which was followed 120 minutes later by a second bolus of the statin coadministered with OATP perpetrator drug rifampicin (67.7 mg). After the first dose, all statins were rapidly cleared from the circulation (hepatic extraction ratio > 0.7) and excreted into the bile. Presence of human-specific atorvastatin metabolites confirmed the metabolic capacity of porcine livers. The predicted biliary clearance of rosuvastatin was found to be closer to the observed biliary clearance. A rank order of the DDI between the various systems upon coadministration with rifampicin could be observed: atorvastatin (AUC ratio 7.2) > rosuvastatin (AUC ratio 3.1) > pitavastatin (AUC ratio 2.6), which is in good agreement with the clinical DDI data. The results from this study demonstrated the applicability of using NMP of porcine livers as a novel preclinical model to study OATP-mediated DDI and its effect on hepatic clearance, biliary excretion, and plasma profile of drugs. SIGNIFICANCE STATEMENT: This study evaluated the use of normothermic machine perfusion (NMP) of porcine livers as a novel preclinical model to study hepatic clearance, biliary excretion, plasma (metabolite) profile of statins, and OATP-mediated DDI. Results showed that NMP of porcine livers is a reliable model to study OATP-mediated DDI. Overall, the rank order of DDI severity indicated in these experiments is in good agreement with clinical data, indicating the potential importance of this new ex vivo model in early drug discovery., (Copyright © 2021 by The Author(s).)
- Published
- 2021
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17. The coronavirus proofreading exoribonuclease mediates extensive viral recombination.
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Gribble J, Stevens LJ, Agostini ML, Anderson-Daniels J, Chappell JD, Lu X, Pruijssers AJ, Routh AL, and Denison MR
- Subjects
- Antiviral Agents pharmacology, COVID-19 virology, Coronavirus Infections virology, Exoribonucleases genetics, Humans, Recombination, Genetic drug effects, SARS-CoV-2 pathogenicity, Viral Nonstructural Proteins genetics, Virus Replication genetics, Coronavirus Infections drug therapy, Exoribonucleases pharmacology, SARS-CoV-2 drug effects, Virus Replication drug effects, COVID-19 Drug Treatment
- Abstract
Recombination is proposed to be critical for coronavirus (CoV) diversity and emergence of SARS-CoV-2 and other zoonotic CoVs. While RNA recombination is required during normal CoV replication, the mechanisms and determinants of CoV recombination are not known. CoVs encode an RNA proofreading exoribonuclease (nsp14-ExoN) that is distinct from the CoV polymerase and is responsible for high-fidelity RNA synthesis, resistance to nucleoside analogues, immune evasion, and virulence. Here, we demonstrate that CoVs, including SARS-CoV-2, MERS-CoV, and the model CoV murine hepatitis virus (MHV), generate extensive and diverse recombination products during replication in culture. We show that the MHV nsp14-ExoN is required for native recombination, and that inactivation of ExoN results in decreased recombination frequency and altered recombination products. These results add yet another critical function to nsp14-ExoN, highlight the uniqueness of the evolved coronavirus replicase, and further emphasize nsp14-ExoN as a central, completely conserved, and vulnerable target for inhibitors and attenuation of SARS-CoV-2 and future emerging zoonotic CoVs., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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18. Durability of Responses after SARS-CoV-2 mRNA-1273 Vaccination.
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Widge AT, Rouphael NG, Jackson LA, Anderson EJ, Roberts PC, Makhene M, Chappell JD, Denison MR, Stevens LJ, Pruijssers AJ, McDermott AB, Flach B, Lin BC, Doria-Rose NA, O'Dell S, Schmidt SD, Neuzil KM, Bennett H, Leav B, Makowski M, Albert J, Cross K, Edara VV, Floyd K, Suthar MS, Buchanan W, Luke CJ, Ledgerwood JE, Mascola JR, Graham BS, and Beigel JH
- Subjects
- 2019-nCoV Vaccine mRNA-1273, Adolescent, Adult, Aged, COVID-19 prevention & control, COVID-19 Vaccines administration & dosage, Humans, Immunization, Secondary, Middle Aged, Spike Glycoprotein, Coronavirus immunology, Th1 Cells physiology, Young Adult, Antibodies, Neutralizing blood, Antibodies, Viral blood, COVID-19 immunology, COVID-19 Vaccines immunology, SARS-CoV-2 immunology
- Published
- 2021
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19. Safety and Immunogenicity of SARS-CoV-2 mRNA-1273 Vaccine in Older Adults.
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Anderson EJ, Rouphael NG, Widge AT, Jackson LA, Roberts PC, Makhene M, Chappell JD, Denison MR, Stevens LJ, Pruijssers AJ, McDermott AB, Flach B, Lin BC, Doria-Rose NA, O'Dell S, Schmidt SD, Corbett KS, Swanson PA 2nd, Padilla M, Neuzil KM, Bennett H, Leav B, Makowski M, Albert J, Cross K, Edara VV, Floyd K, Suthar MS, Martinez DR, Baric R, Buchanan W, Luke CJ, Phadke VK, Rostad CA, Ledgerwood JE, Graham BS, and Beigel JH
- Subjects
- 2019-nCoV Vaccine mRNA-1273, Aged, Antibodies, Neutralizing blood, Antibodies, Viral blood, COVID-19 immunology, COVID-19 Vaccines administration & dosage, Dose-Response Relationship, Drug, Female, Humans, Male, Middle Aged, Neutralization Tests, Spike Glycoprotein, Coronavirus, T-Lymphocytes physiology, COVID-19 prevention & control, COVID-19 Vaccines adverse effects, COVID-19 Vaccines immunology, SARS-CoV-2 immunology
- Abstract
Background: Testing of vaccine candidates to prevent infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in an older population is important, since increased incidences of illness and death from coronavirus disease 2019 (Covid-19) have been associated with an older age., Methods: We conducted a phase 1, dose-escalation, open-label trial of a messenger RNA vaccine, mRNA-1273, which encodes the stabilized prefusion SARS-CoV-2 spike protein (S-2P) in healthy adults. The trial was expanded to include 40 older adults, who were stratified according to age (56 to 70 years or ≥71 years). All the participants were assigned sequentially to receive two doses of either 25 μg or 100 μg of vaccine administered 28 days apart., Results: Solicited adverse events were predominantly mild or moderate in severity and most frequently included fatigue, chills, headache, myalgia, and pain at the injection site. Such adverse events were dose-dependent and were more common after the second immunization. Binding-antibody responses increased rapidly after the first immunization. By day 57, among the participants who received the 25-μg dose, the anti-S-2P geometric mean titer (GMT) was 323,945 among those between the ages of 56 and 70 years and 1,128,391 among those who were 71 years of age or older; among the participants who received the 100-μg dose, the GMT in the two age subgroups was 1,183,066 and 3,638,522, respectively. After the second immunization, serum neutralizing activity was detected in all the participants by multiple methods. Binding- and neutralizing-antibody responses appeared to be similar to those previously reported among vaccine recipients between the ages of 18 and 55 years and were above the median of a panel of controls who had donated convalescent serum. The vaccine elicited a strong CD4 cytokine response involving type 1 helper T cells., Conclusions: In this small study involving older adults, adverse events associated with the mRNA-1273 vaccine were mainly mild or moderate. The 100-μg dose induced higher binding- and neutralizing-antibody titers than the 25-μg dose, which supports the use of the 100-μg dose in a phase 3 vaccine trial. (Funded by the National Institute of Allergy and Infectious Diseases and others; mRNA-1273 Study ClinicalTrials.gov number, NCT04283461.)., (Copyright © 2020 Massachusetts Medical Society.)
- Published
- 2020
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20. An mRNA Vaccine against SARS-CoV-2 - Preliminary Report.
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Jackson LA, Anderson EJ, Rouphael NG, Roberts PC, Makhene M, Coler RN, McCullough MP, Chappell JD, Denison MR, Stevens LJ, Pruijssers AJ, McDermott A, Flach B, Doria-Rose NA, Corbett KS, Morabito KM, O'Dell S, Schmidt SD, Swanson PA 2nd, Padilla M, Mascola JR, Neuzil KM, Bennett H, Sun W, Peters E, Makowski M, Albert J, Cross K, Buchanan W, Pikaart-Tautges R, Ledgerwood JE, Graham BS, and Beigel JH
- Subjects
- 2019-nCoV Vaccine mRNA-1273, Adult, Antibodies, Neutralizing blood, Antibodies, Viral blood, Antibody Formation, Betacoronavirus, COVID-19, COVID-19 Vaccines, Female, Humans, Immunization, Secondary, Male, SARS-CoV-2, T-Lymphocytes immunology, Viral Vaccines adverse effects, Young Adult, Coronavirus Infections prevention & control, Pandemics prevention & control, Pneumonia, Viral prevention & control, RNA, Messenger immunology, Spike Glycoprotein, Coronavirus immunology, Viral Vaccines therapeutic use
- Abstract
Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2019 and spread globally, prompting an international effort to accelerate development of a vaccine. The candidate vaccine mRNA-1273 encodes the stabilized prefusion SARS-CoV-2 spike protein., Methods: We conducted a phase 1, dose-escalation, open-label trial including 45 healthy adults, 18 to 55 years of age, who received two vaccinations, 28 days apart, with mRNA-1273 in a dose of 25 μg, 100 μg, or 250 μg. There were 15 participants in each dose group., Results: After the first vaccination, antibody responses were higher with higher dose (day 29 enzyme-linked immunosorbent assay anti-S-2P antibody geometric mean titer [GMT], 40,227 in the 25-μg group, 109,209 in the 100-μg group, and 213,526 in the 250-μg group). After the second vaccination, the titers increased (day 57 GMT, 299,751, 782,719, and 1,192,154, respectively). After the second vaccination, serum-neutralizing activity was detected by two methods in all participants evaluated, with values generally similar to those in the upper half of the distribution of a panel of control convalescent serum specimens. Solicited adverse events that occurred in more than half the participants included fatigue, chills, headache, myalgia, and pain at the injection site. Systemic adverse events were more common after the second vaccination, particularly with the highest dose, and three participants (21%) in the 250-μg dose group reported one or more severe adverse events., Conclusions: The mRNA-1273 vaccine induced anti-SARS-CoV-2 immune responses in all participants, and no trial-limiting safety concerns were identified. These findings support further development of this vaccine. (Funded by the National Institute of Allergy and Infectious Diseases and others; mRNA-1273 ClinicalTrials.gov number, NCT04283461)., (Copyright © 2020 Massachusetts Medical Society.)
- Published
- 2020
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21. SARS-CoV-2 mRNA vaccine design enabled by prototype pathogen preparedness.
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Corbett KS, Edwards DK, Leist SR, Abiona OM, Boyoglu-Barnum S, Gillespie RA, Himansu S, Schäfer A, Ziwawo CT, DiPiazza AT, Dinnon KH, Elbashir SM, Shaw CA, Woods A, Fritch EJ, Martinez DR, Bock KW, Minai M, Nagata BM, Hutchinson GB, Wu K, Henry C, Bahl K, Garcia-Dominguez D, Ma L, Renzi I, Kong WP, Schmidt SD, Wang L, Zhang Y, Phung E, Chang LA, Loomis RJ, Altaras NE, Narayanan E, Metkar M, Presnyak V, Liu C, Louder MK, Shi W, Leung K, Yang ES, West A, Gully KL, Stevens LJ, Wang N, Wrapp D, Doria-Rose NA, Stewart-Jones G, Bennett H, Alvarado GS, Nason MC, Ruckwardt TJ, McLellan JS, Denison MR, Chappell JD, Moore IN, Morabito KM, Mascola JR, Baric RS, Carfi A, and Graham BS
- Subjects
- 2019-nCoV Vaccine mRNA-1273, Animals, Antibodies, Neutralizing immunology, Betacoronavirus genetics, CD8-Positive T-Lymphocytes immunology, COVID-19, COVID-19 Vaccines, Clinical Trials, Phase III as Topic, Coronavirus Infections genetics, Coronavirus Infections virology, Female, Lung immunology, Lung virology, Mice, Mutation, Nose immunology, Nose virology, Pneumonia, Viral virology, RNA, Messenger genetics, RNA, Viral genetics, SARS-CoV-2, Th1 Cells immunology, Toll-Like Receptor 4 agonists, Toll-Like Receptor 4 immunology, Viral Vaccines chemistry, Viral Vaccines genetics, Betacoronavirus immunology, Coronavirus Infections immunology, Coronavirus Infections prevention & control, Pandemics prevention & control, Pneumonia, Viral immunology, Pneumonia, Viral prevention & control, Viral Vaccines immunology
- Abstract
A vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is needed to control the coronavirus disease 2019 (COVID-19) global pandemic. Structural studies have led to the development of mutations that stabilize Betacoronavirus spike proteins in the prefusion state, improving their expression and increasing immunogenicity
1 . This principle has been applied to design mRNA-1273, an mRNA vaccine that encodes a SARS-CoV-2 spike protein that is stabilized in the prefusion conformation. Here we show that mRNA-1273 induces potent neutralizing antibody responses to both wild-type (D614) and D614G mutant2 SARS-CoV-2 as well as CD8+ T cell responses, and protects against SARS-CoV-2 infection in the lungs and noses of mice without evidence of immunopathology. mRNA-1273 is currently in a phase III trial to evaluate its efficacy.- Published
- 2020
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22. Towards human ex vivo organ perfusion models to elucidate drug pharmacokinetics in health and disease.
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Stevens LJ, Donkers JM, Dubbeld J, Vaes WHJ, Knibbe CAJ, Alwayn IPJ, and van de Steeg E
- Subjects
- Animals, Biomarkers, Pharmacological, Biopsy, Drug Interactions, Humans, Membrane Transport Proteins metabolism, Metabolic Clearance Rate, Pharmaceutical Preparations administration & dosage, Tissue Distribution, Drug Evaluation, Preclinical methods, Liver enzymology, Models, Biological, Pharmaceutical Preparations metabolism, Pharmacokinetics
- Abstract
To predict the absorption, distribution, metabolism and excretion (ADME) profile of candidate drugs a variety of preclinical models can be applied. The ADME and toxicological behavior of newly developed drugs are often investigated prior to assessment in humans, which is associated with long time-lines and high costs. Therefore, good predictions of ADME profiles earlier in the drug development process are very valuable. Good prediction of intestinal absorption and renal and biliary excretion remain especially difficult, as there is an interplay of active transport and metabolism involved. To study these processes, including enterohepatic circulation, ex vivo tissue models are highly relevant and can be regarded as the bridge between in vitro and in vivo models. In this review the current in vitro, in vivo and in more detail ex vivo models for studying pharmacokinetics in health and disease are discussed. Additionally, we propose novel models, i.e., perfused whole-organs, which we envision will generate valuable pharmacokinetic information in the future due to improved translation to the in vivo situation. These machine-perfused organ models will be particularly interesting in combination with biomarkers for assessing the functionality of transporter and CYP450 proteins.
- Published
- 2020
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23. Remdesivir Inhibits SARS-CoV-2 in Human Lung Cells and Chimeric SARS-CoV Expressing the SARS-CoV-2 RNA Polymerase in Mice.
- Author
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Pruijssers AJ, George AS, Schäfer A, Leist SR, Gralinksi LE, Dinnon KH 3rd, Yount BL, Agostini ML, Stevens LJ, Chappell JD, Lu X, Hughes TM, Gully K, Martinez DR, Brown AJ, Graham RL, Perry JK, Du Pont V, Pitts J, Ma B, Babusis D, Murakami E, Feng JY, Bilello JP, Porter DP, Cihlar T, Baric RS, Denison MR, and Sheahan TP
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the novel viral disease COVID-19. With no approved therapies, this pandemic illustrates the urgent need for broad-spectrum antiviral countermeasures against SARS-CoV-2 and future emerging CoVs. We report that remdesivir (RDV) potently inhibits SARS-CoV-2 replication in human lung cells and primary human airway epithelial cultures (EC
50 = 0.01 μM). Weaker activity is observed in Vero E6 cells (EC50 = 1.65 μM) because of their low capacity to metabolize RDV. To rapidly evaluate in vivo efficacy, we engineered a chimeric SARS-CoV encoding the viral target of RDV, the RNA-dependent RNA polymerase of SARS-CoV-2. In mice infected with the chimeric virus, therapeutic RDV administration diminishes lung viral load and improves pulmonary function compared with vehicle-treated animals. These data demonstrate that RDV is potently active against SARS-CoV-2 in vitro and in vivo, supporting its further clinical testing for treatment of COVID-19., Competing Interests: Declaration of Interests The authors affiliated with Gilead Sciences, Inc. are employees of the company and may own company stock., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2020
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24. An orally bioavailable broad-spectrum antiviral inhibits SARS-CoV-2 in human airway epithelial cell cultures and multiple coronaviruses in mice.
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Sheahan TP, Sims AC, Zhou S, Graham RL, Pruijssers AJ, Agostini ML, Leist SR, Schäfer A, Dinnon KH 3rd, Stevens LJ, Chappell JD, Lu X, Hughes TM, George AS, Hill CS, Montgomery SA, Brown AJ, Bluemling GR, Natchus MG, Saindane M, Kolykhalov AA, Painter G, Harcourt J, Tamin A, Thornburg NJ, Swanstrom R, Denison MR, and Baric RS
- Subjects
- Adenosine Monophosphate administration & dosage, Adenosine Monophosphate analogs & derivatives, Alanine administration & dosage, Alanine analogs & derivatives, Animals, Antibiotic Prophylaxis, Betacoronavirus physiology, COVID-19, Cell Line, Coronavirus Infections pathology, Cytidine administration & dosage, Cytidine analogs & derivatives, Disease Models, Animal, Drug Resistance, Viral, Humans, Hydroxylamines, Lung pathology, Mice, Mice, Inbred C57BL, Middle East Respiratory Syndrome Coronavirus physiology, Models, Molecular, Mutation drug effects, Pandemics, Pneumonia, Viral pathology, Primary Cell Culture, RNA, Viral, RNA-Dependent RNA Polymerase chemistry, RNA-Dependent RNA Polymerase genetics, Random Allocation, Respiratory System cytology, SARS-CoV-2, Antiviral Agents administration & dosage, Coronavirus Infections drug therapy, Pneumonia, Viral drug therapy, Ribonucleosides administration & dosage, Virus Replication drug effects
- Abstract
Coronaviruses (CoVs) traffic frequently between species resulting in novel disease outbreaks, most recently exemplified by the newly emerged SARS-CoV-2, the causative agent of COVID-19. Here, we show that the ribonucleoside analog β-d-N
4 -hydroxycytidine (NHC; EIDD-1931) has broad-spectrum antiviral activity against SARS-CoV-2, MERS-CoV, SARS-CoV, and related zoonotic group 2b or 2c bat-CoVs, as well as increased potency against a CoV bearing resistance mutations to the nucleoside analog inhibitor remdesivir. In mice infected with SARS-CoV or MERS-CoV, both prophylactic and therapeutic administration of EIDD-2801, an orally bioavailable NHC prodrug (β-d-N4 -hydroxycytidine-5'-isopropyl ester), improved pulmonary function and reduced virus titer and body weight loss. Decreased MERS-CoV yields in vitro and in vivo were associated with increased transition mutation frequency in viral, but not host cell RNA, supporting a mechanism of lethal mutagenesis in CoV. The potency of NHC/EIDD-2801 against multiple CoVs and oral bioavailability highlights its potential utility as an effective antiviral against SARS-CoV-2 and other future zoonotic CoVs., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).)- Published
- 2020
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25. Remdesivir potently inhibits SARS-CoV-2 in human lung cells and chimeric SARS-CoV expressing the SARS-CoV-2 RNA polymerase in mice.
- Author
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Pruijssers AJ, George AS, Schäfer A, Leist SR, Gralinksi LE, Dinnon KH, Yount BL, Agostini ML, Stevens LJ, Chappell JD, Lu X, Hughes TM, Gully K, Martinez DR, Brown AJ, Graham RL, Perry JK, Du Pont V, Pitts J, Ma B, Babusis D, Murakami E, Feng JY, Bilello JP, Porter DP, Cihlar T, Baric RS, Denison MR, and Sheahan TP
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in 2019 as the causative agent of the novel pandemic viral disease COVID-19. With no approved therapies, this pandemic illustrates the urgent need for safe, broad-spectrum antiviral countermeasures against SARS-CoV-2 and future emerging CoVs. We report that remdesivir (RDV), a monophosphoramidate prodrug of an adenosine analog, potently inhibits SARS-CoV-2 replication in human lung cells and primary human airway epithelial cultures (EC
50 = 0.01 μM). Weaker activity was observed in Vero E6 cells (EC50 = 1.65 μM) due to their low capacity to metabolize RDV. To rapidly evaluate in vivo efficacy, we engineered a chimeric SARS-CoV encoding the viral target of RDV, the RNA-dependent RNA polymerase, of SARS-CoV-2. In mice infected with chimeric virus, therapeutic RDV administration diminished lung viral load and improved pulmonary function as compared to vehicle treated animals. These data provide evidence that RDV is potently active against SARS-CoV-2 in vitro and in vivo , supporting its further clinical testing for treatment of COVID-19.- Published
- 2020
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26. Structural Definition of a Neutralization-Sensitive Epitope on the MERS-CoV S1-NTD.
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Wang N, Rosen O, Wang L, Turner HL, Stevens LJ, Corbett KS, Bowman CA, Pallesen J, Shi W, Zhang Y, Leung K, Kirchdoerfer RN, Becker MM, Denison MR, Chappell JD, Ward AB, Graham BS, and McLellan JS
- Subjects
- Humans, Epitopes metabolism, Middle East Respiratory Syndrome Coronavirus pathogenicity
- Abstract
Middle East respiratory syndrome coronavirus (MERS-CoV) emerged into the human population in 2012 and has caused substantial morbidity and mortality. Potently neutralizing antibodies targeting the receptor-binding domain (RBD) on MERS-CoV spike (S) protein have been characterized, but much less is known about antibodies targeting non-RBD epitopes. Here, we report the structural and functional characterization of G2, a neutralizing antibody targeting the MERS-CoV S1 N-terminal domain (S1-NTD). Structures of G2 alone and in complex with the MERS-CoV S1-NTD define a site of vulnerability comprising two loops, each of which contain a residue mutated in G2-escape variants. Cell-surface binding studies and in vitro competition experiments demonstrate that G2 strongly disrupts the attachment of MERS-CoV S to its receptor, dipeptidyl peptidase-4 (DPP4), with the inhibition requiring the native trimeric S conformation. These results advance our understanding of antibody-mediated neutralization of coronaviruses and should facilitate the development of immunotherapeutics and vaccines against MERS-CoV., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2019
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27. A higher throughput and physiologically relevant two-compartmental human ex vivo intestinal tissue system for studying gastrointestinal processes.
- Author
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Stevens LJ, van Lipzig MMH, Erpelinck SLA, Pronk A, van Gorp J, Wortelboer HM, and van de Steeg E
- Subjects
- Aged, Aged, 80 and over, Animals, Female, Humans, L-Lactate Dehydrogenase metabolism, Lacticaseibacillus rhamnosus, Male, Middle Aged, Permeability, Probiotics, Intestinal Absorption, Intestinal Mucosa metabolism, Models, Biological
- Abstract
A majority of the preclinical intestinal screening models do not properly reflect the complex physiology of the human intestinal tract, resulting in low translational value to the clinical situation. The often used cell lines such as Caco-2 or HT-29 are not well suited to investigate the different processes that predict oral bioavailability in real life, or processes involved in general gut health aspects. Therefore, highly realistic models resembling the human in vivo situation are needed; application of ex vivo intestinal tissue is an interesting and feasible alternative. After previously using porcine intestinal tissue as a predictive model for human intestinal absorption, we now have successfully applied human intestinal tissue into a newly developed InTESTine™ two-compartmental disposable device suitable for standard 6- or 24-well plate format. With this set-up we demonstrated (regional differences in) drug absorption, by using a subset of compounds with known varying F
a (fraction absorbed) values. A rank-order relationship of R2 = 0.85 could be established between the Fa and Papp of these commercially available drugs. Additionally, comparison between the InTESTine system and the established Ussing chamber technology showed a correlation of R2 = 0.94 (10 drugs) with respect to Papp values, indicating good comparison of both models. Besides absorption, intestinal wall metabolism of testosterone (CYP3A4) was determined by showing a linear formation (R2 = 0.99; up to 165 min) of the main metabolites androstenedione and 6Beta-hydroxytestosterone, indicating no loss of metabolic capacity of the intestinal tissue within the system. Enteroendocrine responses were assessed of the satiety hormones GLP-1 and PYY after stimulation with rebaudioside A and casein, resulting in significantly increased secretion to the luminal side as well as to the basolateral side. Incubation with the probiotic strain LGG showed to enhance the viability of the tissue by showing to decrease the LDH secretion compared to blank intestinal tissue. In conclusion, we show that human ex vivo intestinal tissue mounted in the higher throughput InTESTine 6- 24-transwell plate system is easy to handle and a suitable system to study diverse functional GI processes., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
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28. Self-neutralizing oligonucleotides with enhanced cellular uptake.
- Author
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Yanachkov I, Zavizion B, Metelev V, Stevens LJ, Tabatadze Y, Yanachkova M, Wright G, Krichevsky AM, and Tabatadze DR
- Subjects
- Cell Survival drug effects, Cells, Cultured, Dose-Response Relationship, Drug, Humans, Kinetics, Models, Molecular, Molecular Structure, Oligonucleotides chemistry, Solubility, Structure-Activity Relationship, Oligonucleotides pharmacology
- Abstract
There is tremendous potential for oligonucleotide (ON) therapeutics, but low cellular penetration due to their polyanionic nature is a major obstacle. We addressed this problem by developing a new approach for ON charge neutralization in which multiple branched charge-neutralizing sleeves (BCNSs) are attached to the internucleoside phosphates of ON by phosphotriester bonds. The BCNSs are terminated with positively charged amino groups, and are optimized to form ion pairs with the neighboring phosphate groups. The new modified ONs can be prepared by standard automated phosphoramidite chemistry in good yield and purity. They possess good solubility and hybridization properties, are not involved in non-standard intramolecular aggregation, have low cytotoxicity, adequate chemical stability, improved serum stability, and above all, display significantly enhanced cellular uptake. Thus, the new ON derivatives exhibit properties that make them promising candidates for the development of novel therapeutics or research tools for modulation of the expression of target genes.
- Published
- 2017
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29. Understanding the outcomes of a home nursing programme for patients with epidermolysis bullosa: an Australian perspective.
- Author
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Stevens LJ, McKenna S, Marty J, Cowin AJ, and Kopecki Z
- Subjects
- Adolescent, Adult, Australia, Caregivers, Child, Child, Preschool, Female, Humans, Male, Outcome Assessment, Health Care, Program Evaluation, Quality of Life, Young Adult, Epidermolysis Bullosa therapy, Home Nursing
- Abstract
Epidermolysis bullosa (EB) consists of a spectrum of genodermatoses characterised by skin fragility and various degrees of skin and mucous membrane blistering. Minimal trauma and friction can cause extensive blistering in patients with EB, resulting in a number of complications. However, wound management is the main challenge for these patients because of a high risk of infection, fluid loss and potential development of aggressive squamous cell carcinoma (SCC). Indeed, patients with EB have an increased risk for developing skin cancers compared to the general population. In 2012, a home nursing programme was established in Australia to provide assistance to families or patients with severe forms of EB. Nursing care was provided to patients with severe EB during dressing changes in their homes over a period of 2 years. Both families of patients and nurses were surveyed periodically using a developed questionnaire to assess the benefits of this home nursing and its impact on the patients, their families and the nurses. Key findings included a perceived improvement in quality of life, a better provision of support and improved family life management. These findings are the first to highlight the benefits of this national home nursing programme for EB patients within Australia and demonstrate the continued need and benefit of home nursing for patients with severe skin blistering disorders., (© 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.)
- Published
- 2016
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30. Amounts of Artificial Food Colors in Commonly Consumed Beverages and Potential Behavioral Implications for Consumption in Children: Revisited.
- Author
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Stevens LJ, Burgess JR, Stochelski MA, and Kuczek T
- Subjects
- Child, Chromatography, High Pressure Liquid instrumentation, Humans, Beverages analysis, Food Coloring Agents analysis
- Published
- 2015
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31. Amounts of artificial food dyes and added sugars in foods and sweets commonly consumed by children.
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Stevens LJ, Burgess JR, Stochelski MA, and Kuczek T
- Subjects
- Candy statistics & numerical data, Food statistics & numerical data, Humans, Spectrophotometry, United States, United States Food and Drug Administration, Dietary Sucrose analysis, Food Analysis statistics & numerical data, Food Coloring Agents analysis
- Abstract
Artificial food colors (AFCs) are used to color many beverages, foods, and sweets in the United States and throughout the world. In the United States, the Food and Drug Administration (FDA) limits the AFCs allowed in the diet to 9 different colors. The FDA certifies each batch of manufactured AFCs to guarantee purity and safety. The amount certified has risen from 12 mg/capita/d in 1950 to 62 mg/capita/d in 2010. Previously, we reported the amounts of AFCs in commonly consumed beverages. In this article, the amounts of AFCs in commonly consumed foods and sweets are reported. In addition, the amount of sugars in each product is included. Amounts of AFCs reported here along with the beverage data show that many children could be consuming far more dyes than previously thought. Clinical guidance is given to help caregivers avoid AFCs and reduce the amount of sugars in children's diets., (© The Author(s) 2014.)
- Published
- 2015
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32. Detection of the virulent form of AVR3a from Phytophthora infestans following artificial evolution of potato resistance gene R3a.
- Author
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Chapman S, Stevens LJ, Boevink PC, Engelhardt S, Alexander CJ, Harrower B, Champouret N, McGeachy K, Van Weymers PS, Chen X, Birch PR, and Hein I
- Subjects
- Agrobacterium physiology, Apoptosis, DNA Shuffling, Endosomes metabolism, Homozygote, Mutagenesis, Site-Directed, Mutation genetics, Phytophthora infestans isolation & purification, Plant Diseases genetics, Plant Diseases microbiology, Plant Proteins metabolism, Plants, Genetically Modified, Promoter Regions, Genetic genetics, Recombinant Fusion Proteins metabolism, Virulence, Virulence Factors, Directed Molecular Evolution, Disease Resistance genetics, Genes, Plant, Phytophthora infestans metabolism, Phytophthora infestans pathogenicity, Solanum tuberosum genetics, Solanum tuberosum microbiology
- Abstract
Engineering resistance genes to gain effector recognition is emerging as an important step in attaining broad, durable resistance. We engineered potato resistance gene R3a to gain recognition of the virulent AVR3aEM effector form of Phytophthora infestans. Random mutagenesis, gene shuffling and site-directed mutagenesis of R3a were conducted to produce R3a* variants with gain of recognition towards AVR3aEM. Programmed cell death following gain of recognition was enhanced in iterative rounds of artificial evolution and neared levels observed for recognition of AVR3aKI by R3a. We demonstrated that R3a*-mediated recognition responses, like for R3a, are dependent on SGT1 and HSP90. In addition, this gain of response is associated with re-localisation of R3a* variants from the cytoplasm to late endosomes when co-expressed with either AVR3aKI or AVR3aEM a mechanism that was previously only seen for R3a upon co-infiltration with AVR3aKI. Similarly, AVR3aEM specifically re-localised to the same vesicles upon recognition by R3a* variants, but not with R3a. R3a and R3a* provide resistance to P. infestans isolates expressing AVR3aKI but not those homozygous for AVR3aEM.
- Published
- 2014
- Full Text
- View/download PDF
33. Access to wound dressings for patients living with epidermolysis bullosa - an Australian perspective.
- Author
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Stevens LJ
- Subjects
- Australia, Federal Government, Humans, Bandages economics, Epidermolysis Bullosa economics, Epidermolysis Bullosa therapy, Government Programs economics, Health Services Accessibility economics, Wound Healing
- Abstract
Epidermolysis Bullosa (EB) is a rare genetic skin disorder characterised by fragility and blistering of skin and mucous membranes. Skin can blister and shear away from minimal friction, trauma and every day activities. The disease causes a wide range of complications but wound care is the major challenge to severe EB, and good wound care is an essential part of wound management. The goal of wound care was to choose a product that protects the fragile skin, limits friction, decreases pain and promotes healing. However, access to wound dressings for those people living with EB is challenging. This article discusses the availability of EB dressings in a number of countries around the world and also describes an innovative National Epidermolysis Bullosa Dressings Scheme (NEBDS) in Australia, which aims to improve the quality of life of people with EB, by reducing the financial burden associated with the provision of dressings accordingly., (© 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.)
- Published
- 2014
- Full Text
- View/download PDF
34. Amounts of artificial food colors in commonly consumed beverages and potential behavioral implications for consumption in children.
- Author
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Stevens LJ, Burgess JR, Stochelski MA, and Kuczek T
- Subjects
- Attention Deficit Disorder with Hyperactivity chemically induced, Child, Food Coloring Agents adverse effects, Humans, Spectrophotometry, United States, Beverages analysis, Food Coloring Agents analysis
- Abstract
Artificial food colors (AFCs) are widely used to color foods and beverages. The amount of AFCs the Food and Drug Administration has certified over the years has increased more than 5-fold since 1950 (12 mg/capita/day) to 2012 (68 mg/capita/day). In the past 38 years, there have been studies of adverse behavioral reactions such as hyperactivity in children to double-blind challenges with AFCs. Studies that used 50 mg or more of AFCs as the challenge showed a greater negative effect on more children than those which used less. The study reported here is the first to quantify the amounts of AFCs in foods (specifically in beverages) commonly consumed by children in the United States. Consumption data for all foods would be helpful in the design of more challenge studies. The data summarized here should help clinicians advise parents about AFCs and beverage consumption.
- Published
- 2014
- Full Text
- View/download PDF
35. Mechanisms of behavioral, atopic, and other reactions to artificial food colors in children.
- Author
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Stevens LJ, Kuczek T, Burgess JR, Stochelski MA, Arnold LE, and Galland L
- Subjects
- Attention Deficit Disorder with Hyperactivity diagnosis, Child, Food Coloring Agents administration & dosage, Food Coloring Agents pharmacokinetics, Food Hypersensitivity complications, Humans, Intestinal Absorption, Attention Deficit Disorder with Hyperactivity chemically induced, Child Behavior drug effects, Food Coloring Agents adverse effects
- Abstract
This review examines the research on mechanisms by which artificial food colors (AFCs) and common foods may cause behavioral changes in children with and without attention-deficit/hyperactivity disorder (ADHD). Children with ADHD show excess inattention, impulsivity, and hyperactivity. Studies have shown that a subgroup of children (with or without ADHD) react adversely to challenges with AFCs. Many early studies found few children who reacted to challenges with 20-40 mg of AFCs. However, studies using at least 50 mg of AFCs showed a greater percentage of children who reacted to the challenge. Three types of potential mechanisms are explored: toxicological, antinutritional, and hypersensitivity. Suggestions for future studies in animals and/or children include dose studies as well as studies to determine the effects of AFCs on the immune system, the intestinal mucosa, and nutrient absorption. Given the potential negative behavioral effects of AFCs, it is important to determine why some children may be more sensitive to AFCs than others and to identify the tolerable upper limits of exposure for children in general and for children at high risk., (© 2013 International Life Sciences Institute.)
- Published
- 2013
- Full Text
- View/download PDF
36. A secreted MMP is required for reepithelialization during wound healing.
- Author
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Stevens LJ and Page-McCaw A
- Subjects
- Animals, Basement Membrane metabolism, Extracellular Signal-Regulated MAP Kinases metabolism, Humans, MAP Kinase Kinase 4 metabolism, Matrix Metalloproteinase 1 genetics, Up-Regulation, Drosophila melanogaster metabolism, Epidermis metabolism, Matrix Metalloproteinase 1 metabolism, Models, Animal, Wound Healing
- Abstract
Matrix metalloproteinases (MMPs) are extracellular proteases highly expressed at wound sites. However, the precise function of MMPs during reepithelialization in vivo has been elusive in mammalian models because of the high level of redundancy among the 24 mammalian MMPs. For this reason we used Drosophila melanogaster, whose genome encodes only two MMPs-one secreted type (Mmp1) and one membrane-anchored type (Mmp2)-to study the function and regulation of the secreted class of MMPs in vivo. In the absence of redundancy, we found that the Drosophila secreted MMP, Mmp1, is required in the epidermis to facilitate reepithelialization by remodeling the basement membrane, promoting cell elongation and actin cytoskeletal reorganization, and activating extracellular signal-regulated kinase signaling. In addition, we report that the jun N-terminal kinase (JNK) pathway upregulates Mmp1 expression after wounding, but that Mmp1 is expressed independent of the JNK pathway in unwounded epidermis. When the JNK pathway is ectopically activated to overexpress Mmp1, the rate of healing is accelerated in an Mmp1-dependent manner. A primary function of Mmp1, under the control of the JNK pathway, is to promote basement membrane repair, which in turn may permit cell migration and the restoration of a continuous tissue.
- Published
- 2012
- Full Text
- View/download PDF
37. Solving the puzzle of attention deficit hyperactivity disorder.
- Author
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Stevens LJ, Kuczek T, and Arnold LE
- Subjects
- Animals, Attention Deficit Disorder with Hyperactivity therapy, Food Coloring Agents toxicity, Humans, Attention Deficit Disorder with Hyperactivity chemically induced
- Published
- 2011
- Full Text
- View/download PDF
38. Dietary sensitivities and ADHD symptoms: thirty-five years of research.
- Author
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Stevens LJ, Kuczek T, Burgess JR, Hurt E, and Arnold LE
- Subjects
- Biomedical Research trends, Child, Humans, Attention Deficit Disorder with Hyperactivity diet therapy, Attention Deficit Disorder with Hyperactivity etiology, Benzoates adverse effects, Food Coloring Agents adverse effects, Food Hypersensitivity complications, Food Preservatives adverse effects
- Abstract
Artificial food colors (AFCs) have not been established as the main cause of attention-deficit hyperactivity disorder (ADHD), but accumulated evidence suggests that a subgroup shows significant symptom improvement when consuming an AFC-free diet and reacts with ADHD-type symptoms on challenge with AFCs. Of children with suspected sensitivities, 65% to 89% reacted when challenged with at least 100 mg of AFC. Oligoantigenic diet studies suggested that some children in addition to being sensitive to AFCs are also sensitive to common nonsalicylate foods (milk, chocolate, soy, eggs, wheat, corn, legumes) as well as salicylate-containing grapes, tomatoes, and orange. Some studies found "cosensitivity" to be more the rule than the exception. Recently, 2 large studies demonstrated behavioral sensitivity to AFCs and benzoate in children both with and without ADHD. A trial elimination diet is appropriate for children who have not responded satisfactorily to conventional treatment or whose parents wish to pursue a dietary investigation.
- Published
- 2011
- Full Text
- View/download PDF
39. Omega-3 fatty acid status in attention-deficit/hyperactivity disorder.
- Author
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Antalis CJ, Stevens LJ, Campbell M, Pazdro R, Ericson K, and Burgess JR
- Subjects
- Adult, Attention Deficit Disorder with Hyperactivity epidemiology, Behavior, Case-Control Studies, Diet, Fatty Acids, Unsaturated blood, Fatty Acids, Unsaturated deficiency, Feeding Behavior, Female, Food Analysis, Humans, Male, Skin Abnormalities epidemiology, Thirst physiology, Attention Deficit Disorder with Hyperactivity blood, Fatty Acids, Omega-3 blood
- Abstract
Lower levels of long-chain polyunsaturated fatty acids, particularly omega-3 fatty acids, in blood have repeatedly been associated with a variety of behavioral disorders including attention-deficit/hyperactivity disorder (ADHD). The exact nature of this relationship is not yet clear. We have studied children with ADHD who exhibited skin and thirst symptoms classically associated with essential fatty acid (EFA) deficiency, altered plasma and red blood cell fatty acid profiles, and dietary intake patterns that do not differ significantly from controls. This led us to focus on a potential metabolic insufficiency as the cause for the altered fatty acid phenotype. Here we review previous work and present new data expanding our observations into the young adult population. The frequency of thirst and skin symptoms was greater in newly diagnosed individuals with ADHD (n = 35) versus control individuals without behavioral problems (n = 112) drawn from the Purdue student population. A follow up case-control study with participants willing to provide a blood sample, a urine sample, a questionnaire about their general health, and dietary intake records was conducted with balancing based on gender, age, body mass index, smoking and ethnicity. A number of biochemical measures were analyzed including status markers for several nutrients and antioxidants, markers of oxidative stress, inflammation markers, and fatty acid profiles in the blood. The proportion of omega-3 fatty acids was found to be significantly lower in plasma phospholipids and erythrocytes in the ADHD group versus controls whereas saturated fatty acid proportions were higher. Intake of saturated fat was 30% higher in the ADHD group, but intake of all other nutrients was not different. Surprisingly, no evidence of elevated oxidative stress was found based on analysis of blood and urine samples. Indeed, serum ferritin, magnesium, and ascorbate concentrations were higher in the ADHD group, but iron, zinc, and vitamin B6 were not different. Our brief survey of biochemical and nutritional parameters did not give us any insight into the etiology of lower omega-3 fatty acids, but considering the consistency of the observation in multiple ADHD populations continued research in this field is encouraged.
- Published
- 2006
- Full Text
- View/download PDF
40. Omega-3 fatty acids in boys with behavior, learning, and health problems.
- Author
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Stevens LJ, Zentall SS, Abate ML, Kuczek T, and Burgess JR
- Subjects
- Child, Child Behavior, Fatty Acids, Omega-6, Fatty Acids, Unsaturated blood, Humans, Male, Phospholipids blood, Child Behavior Disorders blood, Fatty Acids, Omega-3 blood, Health, Learning physiology
- Abstract
The purpose of the study reported here was to compare behavior, learning, and health problems in boys ages 6 to 12 with lower plasma phospholipid total omega-3 or total omega-6 fatty acid levels with those boys with higher levels of these fatty acids. A greater frequency of symptoms indicative of essential fatty acid deficiency was reported by the parents of subjects with lower plasma omega-3 or omega-6 fatty acid concentrations than those with higher levels. A greater number of behavior problems, assessed by the Conners' Rating Scale, temper tantrums, and sleep problems were reported in subjects with lower total omega-3 fatty acid concentrations. Additionally, more learning and health problems were found in subjects with lower total omega-3 fatty acid concentrations. (Only more colds and more antibiotic use were reported by those subjects with lower total omega-6 fatty acids). These findings are discussed in relation to recent findings for omega-3 experimentally deprived animals.
- Published
- 1996
- Full Text
- View/download PDF
41. Conflict resolution abilities of children with specific language impairment and children with normal language.
- Author
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Stevens LJ and Bliss LS
- Subjects
- Child, Cognition, Female, Humans, Language Tests, Male, Conflict, Psychological, Language, Language Disorders diagnosis, Problem Solving
- Abstract
This study explored the conflict resolution ability of 30 children with specific language impairment (SLI) and 30 children with normal language (NL) in grades 3 through 7. The children participated in a hypothetical problem-solving activity in which an imaginary conflict was presented and a hypothetical solution was required. They also engaged in role enactments of conflicts. The children with SLI suggested fewer types of strategies to resolve hypothetical conflicts than their peers with NL. The groups did not differ in the number of strategy types used in the role-enactment contexts. The children with receptive and expressive SLI performed more poorly than the children with primarily expressive language deficits only on the role-enactment task. Similarities and differences in types of strategy used by the children with SLI and those with NL were found in both tasks. Explanations are offered for these findings.
- Published
- 1995
- Full Text
- View/download PDF
42. Learning disabilities: the experts speak out.
- Author
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Tucker J, Stevens LJ, and Ysseldyke JE
- Subjects
- Child, Child, Preschool, Diagnosis, Differential, Humans, Infant, Learning Disabilities epidemiology, United States, Learning Disabilities diagnosis
- Published
- 1983
- Full Text
- View/download PDF
43. Midtrimester amniocentesis: obstetric outcome and neonatal neurobehavioral status.
- Author
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Finegan JK, Quarrington BJ, Hughes HE, Rudd NL, Stevens LJ, Weksberg R, and Doran TA
- Subjects
- Adult, Anthropometry, Female, Fetal Death etiology, Humans, Infant, Premature, Longitudinal Studies, Pregnancy, Pregnancy Complications etiology, Prospective Studies, Psychological Tests, Amniocentesis adverse effects, Behavior, Infant, Newborn psychology
- Abstract
The possible effects of midtrimester genetic amniocentesis on neurobehavioral status were studied in newborn infants of women who had had the procedure (N = 100) and in newborn infants of women who had declined the test (N = 56). Brazelton's Neonatal Behavioral Assessment Scale was administered to newborn infants born at term and did not reveal consequences of amniocentesis on neonatal orientation, range of state, motor ability, autonomic regulation, regulation of state, response decrement, or reflexes. Information on obstetric complications also was obtained. The findings raised questions regarding the temporal relationship between amniocentesis and fetal loss and focused attention on preterm birth as a potential risk that warrants further investigation. This study provides the foundation for our prospective longitudinal follow-up in which the cohort will be reassessed later in infancy and in childhood.
- Published
- 1984
- Full Text
- View/download PDF
44. Large field trial with microencapsulated sex pheromone to prevent mating of the gypsy moth.
- Author
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Beroza M, Hood CS, Trefrey D, Leonard DE, Knipling EF, Klassen W, and Stevens LJ
- Subjects
- Animals, Female, Male, Reproduction, Lepidoptera physiology, Pheromones administration & dosage
- Published
- 1974
- Full Text
- View/download PDF
45. Infant outcome following mid-trimester amniocentesis: development and physical status at age six months.
- Author
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Finegan JA, Quarrington BJ, Hughes HE, Rudd NL, Stevens LJ, Weksberg R, and Doran TA
- Subjects
- Adult, Body Constitution, Female, Humans, Infant, Motor Skills, Pregnancy, Pregnancy Trimester, Second, Skin Diseases etiology, Temperament, Amniocentesis adverse effects, Child Development
- Abstract
Ninety-one infants whose mothers had had amniocentesis, because age increased their risk for a fetal chromosome abnormality, were compared with 53 infants whose mothers chose not to have the test. Mental and motor development and temperament were studied to assess potential influence of amniocentesis on the brain. Physical growth was assessed and the infants were examined for orthopaedic abnormalities and needle injury. The results indicated that amniocentesis does not appear to influence infant mental and motor development, temperament, physical growth or the risk of orthopaedic abnormalities. However, amniocentesis is not entirely free of risk because several of the infants had needle marks. Reassessment of the cohort at age 4 and 7 years and will provide information on the potential longer term consequences of mid-trimester amniocentesis.
- Published
- 1985
- Full Text
- View/download PDF
46. A report on a family with a (1;2) translocation: cytologic and linkage analysis.
- Author
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Thompson MW, Falk CT, Worton RG, Stevens LJ, Allen FH Jr, and Surana RB
- Subjects
- Abnormalities, Multiple genetics, Child, Preschool, Chromosome Mapping, Female, Humans, Intellectual Disability genetics, Male, Pedigree, Phenotype, Chromosome Aberrations, Chromosomes, Human, 1-3, Genes, Translocation, Genetic
- Published
- 1976
47. Autosomal imbalance with a near-normal phenotype: the small effect of trisomy for the short arm of chromosome 18.
- Author
-
Gardner RJ, Rudd NL, Stevens LJ, and Worton RG
- Subjects
- Adult, Female, Humans, Infant, Intelligence, Pedigree, Phenotype, Abnormalities, Multiple genetics, Chromosomes, Human, 16-18, Chromosomes, Human, 6-12 and X, Translocation, Genetic, Trisomy
- Published
- 1978
48. Monitoring pesticides in soils from areas ofregular, limited, and no pesticide use.
- Author
-
Stevens LJ, Collier CW, and Woodam DW
- Subjects
- Acetates analysis, Arsenic analysis, Chromatography, Gas, DDT analysis, Dieldrin analysis, Hydrocarbons, Halogenated analysis, Monitoring, Physiologic, Phenols analysis, Phosphoric Acids analysis, United States, Pesticides analysis, Soil analysis
- Published
- 1970
49. Preliminary study of mercury residues in soils where mercury seed treatments have been used.
- Author
-
Sand PF, Wiersma GB, Tai H, and Stevens LJ
- Subjects
- United States, Mercury analysis, Pesticide Residues analysis, Soil analysis
- Published
- 1971
50. An electron-microscopic study of the acrocentrics in patients with Down's syndrome.
- Author
-
Stevens LJ
- Subjects
- Humans, Male, Microscopy, Electron, Sex Chromosomes, Chromosomes, Human, 21-22 and Y, Down Syndrome
- Published
- 1968
- Full Text
- View/download PDF
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