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1.
Circulation ; 145(23): 1720-1737, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35502657

RESUMEN

BACKGROUND: Vascular smooth muscle cell (VSMC) phenotypic switching contributes to cardiovascular diseases. Epigenetic regulation is emerging as a key regulatory mechanism, with the methylcytosine dioxygenase TET2 acting as a master regulator of smooth muscle cell phenotype. The histone acetyl-transferases p300 and CREB-binding protein (CBP) are highly homologous and often considered to be interchangeable, and their roles in smooth muscle cell phenotypic regulation are not known. METHODS: We assessed the roles of p300 and CBP in human VSMC with knockdown, in inducible smooth muscle-specific knockout mice (inducible knockout [iKO]; p300iKO or CBPiKO), and in samples of human intimal hyperplasia. RESULTS: P300, CBP, and histone acetylation were differently regulated in VSMCs undergoing phenotypic switching and in vessel remodeling after vascular injury. Medial p300 expression and activity were repressed by injury, but CBP and histone acetylation were induced in neointima. Knockdown experiments revealed opposing effects of p300 and CBP in the VSMC phenotype: p300 promoted contractile protein expression and inhibited migration, but CBP inhibited contractile genes and enhanced migration. p300iKO mice exhibited severe intimal hyperplasia after arterial injury compared with controls, whereas CBPiKO mice were entirely protected. In normal aorta, p300iKO reduced, but CBPiKO enhanced, contractile protein expression and contractility compared with controls. Mechanistically, we found that these histone acetyl-transferases oppositely regulate histone acetylation, DNA hydroxymethylation, and PolII (RNA polymerase II) binding to promoters of differentiation-specific contractile genes. Our data indicate that p300 and TET2 function together, because p300 was required for TET2-dependent hydroxymethylation of contractile promoters, and TET2 was required for p300-dependent acetylation of these loci. TET2 coimmunoprecipitated with p300, and this interaction was enhanced by rapamycin but repressed by platelet-derived growth factor (PDGF) treatment, with p300 promoting TET2 protein stability. CBP did not associate with TET2, but instead facilitated recruitment of histone deacetylases (HDAC2, HDAC5) to contractile protein promoters. Furthermore, CBP inhibited TET2 mRNA levels. Immunostaining of cardiac allograft vasculopathy samples revealed that p300 expression is repressed but CBP is induced in human intimal hyperplasia. CONCLUSIONS: This work reveals that p300 and CBP serve nonredundant and opposing functions in VSMC phenotypic switching and coordinately regulate chromatin modifications through distinct functional interactions with TET2 or HDACs. Targeting specific histone acetyl-transferases may hold therapeutic promise for cardiovascular diseases.


Asunto(s)
Enfermedades Cardiovasculares , Músculo Liso Vascular , Factores de Transcripción p300-CBP/metabolismo , Acetilación , Animales , Proteína de Unión a CREB/genética , Proteína de Unión a CREB/metabolismo , Enfermedades Cardiovasculares/metabolismo , Ensamble y Desensamble de Cromatina , Proteínas Contráctiles/metabolismo , Epigénesis Genética , Histonas/metabolismo , Humanos , Hiperplasia/metabolismo , Ratones , Ratones Noqueados , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo
2.
Proc Natl Acad Sci U S A ; 117(43): 26946-26954, 2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-33028676

RESUMEN

Remdesivir is a broad-spectrum antiviral nucleotide prodrug that has been clinically evaluated in Ebola virus patients and recently received emergency use authorization (EUA) for treatment of COVID-19. With approvals from the Federal Select Agent Program and the Centers for Disease Control and Prevention's Institutional Biosecurity Board, we characterized the resistance profile of remdesivir by serially passaging Ebola virus under remdesivir selection; we generated lineages with low-level reduced susceptibility to remdesivir after 35 passages. We found that a single amino acid substitution, F548S, in the Ebola virus polymerase conferred low-level reduced susceptibility to remdesivir. The F548 residue is highly conserved in filoviruses but should be subject to specific surveillance among novel filoviruses, in newly emerging variants in ongoing outbreaks, and also in Ebola virus patients undergoing remdesivir therapy. Homology modeling suggests that the Ebola virus polymerase F548 residue lies in the F-motif of the polymerase active site, a region that was previously identified as susceptible to resistance mutations in coronaviruses. Our data suggest that molecular surveillance of this region of the polymerase in remdesivir-treated COVID-19 patients is also warranted.


Asunto(s)
Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , Antivirales/farmacología , Betacoronavirus/enzimología , Ebolavirus/enzimología , ARN Polimerasa Dependiente del ARN/química , Proteínas no Estructurales Virales/química , Adenosina Monofosfato/farmacología , Alanina/farmacología , Betacoronavirus/química , Línea Celular , Tolerancia a Medicamentos/genética , Ebolavirus/efectos de los fármacos , Ebolavirus/genética , Humanos , Modelos Moleculares , Mutación , ARN Polimerasa Dependiente del ARN/genética , SARS-CoV-2 , Proteínas no Estructurales Virales/genética , Replicación Viral/efectos de los fármacos
3.
Biol Lett ; 18(11): 20220199, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36349580

RESUMEN

In flying insects, head stabilization is an essential reflex that helps to reduce motion blur during fast aerial manoeuvres. This reflex is multimodal and requires the integration of visual and antennal mechanosensory feedback in hawkmoths, each operating as a negative-feedback-control loop. As in any negative-feedback system, the head stabilization system possesses inherent oscillatory dynamics that depend on the rate at which the sensorimotor components of the reflex operate. Consistent with this expectation, we observed small-amplitude oscillations in the head motion (or head wobble) of the oleander hawkmoth, Daphnis nerii, which are accentuated when sensory feedback is aberrant. Here, we show that these oscillations emerge from the inherent dynamics of the multimodal reflex underlying gaze stabilization, and that the amplitude of head wobble is a function of both the visual feedback and antennal mechanosensory feedback from the Johnston's organs. Our data support the hypothesis that head wobble results from a multimodal, dynamically stabilized reflex loop that mediates head positioning.


Asunto(s)
Manduca , Mariposas Nocturnas , Animales , Vuelo Animal , Antenas de Artrópodos , Reflejo , Cabeza
5.
Artículo en Inglés | MEDLINE | ID: mdl-32529485

RESUMEN

Flying insects occupy both diurnal and nocturnal niches, and their visual systems encounter distinct challenges in both conditions. Visual adaptations, such as superposition eyes of moths, enhance sensitivity to low light levels but trade off with spatial and temporal resolution. Conversely, apposition eyes of butterflies enable high spatial resolution but are poorly sensitive in dim light. Although diel activity patterns of insects influence visual processing, their role in evolution of visual systems is relatively unexplored. Lepidopteran insects present an excellent system to study how diel activity patterns and phylogenetic position influence the visual transduction system. We addressed this question by comparing electroretinography measurements of temporal response profiles of diverse Lepidoptera to light stimuli that were flickering at different frequencies. Our data show that the eyes of diurnal butterflies are sensitive to visual stimuli of higher temporal frequencies than nocturnal moths. Hesperiid skippers, which are typically diurnal or crepuscular, exhibit intermediate phenotypes with peak sensitivity across broader frequency range. Across all groups, species within families exhibited similar phenotypes irrespective of diel activity. Thus, Lepidopteran photoreceptors may have diversified under phylogenetic constraints, and shifts in their sensitivity to higher temporal frequencies occurred concomitantly with the evolution of diurnal lifestyles.


Asunto(s)
Lepidópteros/fisiología , Adaptación Fisiológica , Animales , Evolución Biológica , Fusión de Flicker/fisiología , Fotoperiodo , Células Fotorreceptoras/fisiología , Visión Ocular , Percepción Visual
6.
Appl Environ Microbiol ; 85(23)2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31540982

RESUMEN

Since the discovery of penicillin, microbes have been a source of antibiotics that inhibit the growth of pathogens. However, with the evolution of multidrug-resistant (MDR) strains, it remains unclear if there is an abundant or limited supply of natural products to be discovered that are effective against MDR isolates. To identify strains that are antagonistic to pathogens, we examined a set of 471 globally derived environmental Pseudomonas strains (env-Ps) for activity against a panel of 65 pathogens including Achromobacter spp., Burkholderia spp., Pseudomonas aeruginosa, and Stenotrophomonas spp. isolated from the lungs of cystic fibrosis (CF) patients. From more than 30,000 competitive interactions, 1,530 individual inhibitory events were observed. While strains from water habitats were not proportionate in antagonistic activity, MDR CF-derived pathogens (CF-Ps) were less susceptible to inhibition by env-Ps, suggesting that fewer natural products are effective against MDR strains. These results advocate for a directed strategy to identify unique drugs. To facilitate discovery of antibiotics against the most resistant pathogens, we developed a workflow in which phylogenetic and antagonistic data were merged to identify strains that inhibit MDR CF-Ps and subjected those env-Ps to transposon mutagenesis. Six different biosynthetic gene clusters (BGCs) were identified from four strains whose products inhibited pathogens including carbapenem-resistant P. aeruginosa BGCs were rare in databases, suggesting the production of novel antibiotics. This strategy can be utilized to facilitate the discovery of needed antibiotics that are potentially active against the most drug-resistant pathogens.IMPORTANCE Carbapenem-resistant P. aeruginosa is difficult to treat and has been deemed by the World Health Organization as a priority one pathogen for which antibiotics are most urgently needed. Although metagenomics and bioinformatic studies suggest that natural bacteria remain a source of novel compounds, the identification of genes and their products specific to activity against MDR pathogens remains problematic. Here, we examine water-derived pseudomonads and identify gene clusters whose compounds inhibit CF-derived MDR pathogens, including carbapenem-resistant P. aeruginosa.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple , Pseudomonas/genética , Antibiosis , Pruebas de Sensibilidad Microbiana , Pseudomonas/química
7.
Molecules ; 24(17)2019 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-31480658

RESUMEN

Due to their ability to inhibit viral DNA or RNA replication, nucleoside analogues have been used for decades as potent antiviral therapeutics. However, one of the major limitations of nucleoside analogues is the development of antiviral resistance. In that regard, flexible nucleoside analogues known as "fleximers" have garnered attention over the years due to their ability to survey different amino acids in enzyme binding sites, thus overcoming the potential development of antiviral resistance. Acyclic fleximers have previously demonstrated antiviral activity against numerous viruses including Middle East Respiratory Syndrome coronavirus (MERS-CoV), Ebola virus (EBOV), and, most recently, flaviviruses such as Dengue (DENV) and Yellow Fever Virus (YFV). Due to these interesting results, a Structure Activity Relationship (SAR) study was pursued in order to analyze the effect of the pyrimidine functional group and acyl protecting group on antiviral activity, cytotoxicity, and conformation. The results of those studies are presented herein.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Pirimidinas/química , Pirimidinas/farmacología , Línea Celular Tumoral , Ebolavirus/efectos de los fármacos , Humanos , Indicadores y Reactivos , Lípidos/química , Conformación Molecular , Espectroscopía de Protones por Resonancia Magnética , Relación Estructura-Actividad
8.
Appl Environ Microbiol ; 83(2)2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27881418

RESUMEN

Pseudomonas aeruginosa is an opportunistic pathogen which is evolving resistance to many currently used antibiotics. While much research has been devoted to the roles of pathogenic P. aeruginosa in cystic fibrosis (CF) patients, less is known of its ecological properties. P. aeruginosa dominates the lungs during chronic infection in CF patients, yet its abundance in some environments is less than that of other diverse groups of pseudomonads. Here, we sought to determine if clinical isolates of P. aeruginosa are vulnerable to environmental pseudomonads that dominate soil and water habitats in one-to-one competitions which may provide a source of inhibitory factors. We isolated a total of 330 pseudomonads from diverse habitats of soil and freshwater ecosystems and competed these strains against one another to determine their capacity for antagonistic activity. Over 900 individual inhibitory events were observed. Extending the analysis to P. aeruginosa isolates revealed that clinical isolates, including ones with increased alginate production, were susceptible to competition by multiple environmental strains. We performed transposon mutagenesis on one isolate and identified an ∼14.8-kb locus involved in antagonistic activity. Only two other environmental isolates were observed to carry the locus, suggesting the presence of additional unique compounds or interactions among other isolates involved in outcompeting P. aeruginosa This collection of strains represents a source of compounds that are active against multiple pathogenic strains. With the evolution of resistance of P. aeruginosa to currently used antibiotics, these environmental strains provide opportunities for novel compound discovery against drug-resistant clinical strains. IMPORTANCE: We demonstrate that clinical CF-derived isolates of P. aeruginosa are susceptible to competition in the presence of environmental pseudomonads. We observed that many diverse environmental strains exhibited varied antagonistic profiles against a panel of clinical P. aeruginosa isolates, suggesting the presence of distinct mechanisms of inhibition among these ecological strains. Understanding the properties of these antagonistic events offers the potential for discoveries of antimicrobial compounds or metabolic pathways important to the development of novel treatments for P. aeruginosa infections.


Asunto(s)
Antibiosis , Fibrosis Quística/microbiología , Microbiología Ambiental , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/fisiología , Pseudomonas/fisiología , Humanos
9.
Bioorg Med Chem Lett ; 27(12): 2800-2802, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28465098

RESUMEN

Fleximers, a novel type of flexible nucleoside that have garnered attention due to their unprecedented activity against human coronaviruses, have now exhibited highly promising levels of activity against filoviruses. The Flex-nucleoside was the most potent against recombinant Ebola virus in Huh7 cells with an EC50=2µM, while the McGuigan prodrug was most active against Sudan virus-infected HeLa cells with an EC50 of 7µM.


Asunto(s)
Antivirales/farmacología , Ebolavirus/efectos de los fármacos , Nucleósidos/farmacología , Antivirales/síntesis química , Antivirales/química , Línea Celular , Relación Dosis-Respuesta a Droga , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Nucleósidos/síntesis química , Nucleósidos/química , Relación Estructura-Actividad
10.
Int Psychogeriatr ; 28(2): 341-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26250473

RESUMEN

BACKGROUND: Individuals with Lewy body dementia (LBD) typically exhibit impairments in attentional and executive function. Current pharmacological treatments have limited efficacy, with associated side effects. Transcranial direct current stimulation (tDCS) may represent an alternative treatment, as cognitive improvements have been demonstrated in healthy individuals. However, no studies to date have assessed the feasibility of tDCS in an LBD population. The aim of this preliminary study, therefore, was to assess the tolerability of tDCS, as well as its effects upon attentional and visuoperceptual performance, in LBD patients. METHODS: Thirteen participants completed attentional (simple reaction time, choice reaction time, and digit vigilance) and forced-choice visuoperceptual (angle and motion perception) tasks before and after one 20-min session of active tDCS (0.08 mA/cm2). The anodal electrode was applied to the left dorsolateral prefrontal cortex and the cathodal electrode was applied to the right deltoid. Attentional (task accuracy and reaction time to correct answers) and visuoperceptual (task accuracy and difficulty) outcome measures were compared using paired t-tests. RESULTS: All participants tolerated stimulation and did not report any side effects during or immediately after stimulation. Post-stimulation improvements were observed in the choice reaction time (increased percentage of correct answers; p = 0.01) and digit vigilance (reduced mean reaction time to correct answers; p = 0.02) attention tasks. Visuoperceptual task performance did not improve (all p-values > 0.05). CONCLUSIONS: Attentional, but not visuoperceptual, improvements were observed following stimulation in LBD patients. Larger-scale, placebo-controlled trials are needed to confirm whether tDCS is a useful treatment option for attentional deficits in LBD.


Asunto(s)
Atención/fisiología , Enfermedad por Cuerpos de Lewy/terapia , Análisis y Desempeño de Tareas , Estimulación Transcraneal de Corriente Directa , Percepción Visual/fisiología , Anciano , Estudios de Factibilidad , Femenino , Humanos , Enfermedad por Cuerpos de Lewy/fisiopatología , Masculino , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tiempo de Reacción/fisiología , Resultado del Tratamiento
11.
Nucleic Acids Res ; 41(22): 10157-69, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24021630

RESUMEN

Exposure to genotoxic agents, such as ionizing radiation (IR), produces double-strand breaks, repaired predominantly in mammalian cells by non-homologous end-joining (NHEJ). Ku70 was identified as an interacting partner of a proteolytic Cyclin E (CycE) fragment, p18CycE. p18CycE endogenous generation during IR-induced apoptosis in leukemic cells and its stable expression in epithelial tumor cells sensitized to IR. γH2AX IR-induced foci (IRIFs) and comet assays indicated ineffective NHEJ DNA repair in p18CycE-expressing cells. DNA pull-down and chromatin recruitment assays revealed that retention of NHEJ factors to double-strand breaks, but not recruitment, was diminished. Similarly, IRIFs of phosphorylated T2609 and S2056-DNA-PKcs and its target S1778-53BP1 were greatly decreased in p18CycE-expressing cells. As a result, DNA-PKcs chromatin association was also increased. 53BP1 IRIFs were suppressed when p18CycE was generated in leukemic cells and in epithelial cells stably expressing p18CycE. Ataxia telangiectasia mutated was activated but not its 53BP1 and MDC1 targets. These data indicate a profound influence of p18CycE on NHEJ through its interference with DNA-PKcs conformation and/or dimerization, which is required for effective DNA repair, making the p18CycE-expressing cells more IR sensitive. These studies provide unique mechanistic insights into NHEJ misregulation in human tumor cells, in which defects in NHEJ core components are rare.


Asunto(s)
Cromatina/metabolismo , Ciclina E/metabolismo , Reparación del ADN por Unión de Extremidades , Proteínas Adaptadoras Transductoras de Señales , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteínas de Ciclo Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de la radiación , Daño del ADN , Proteína Quinasa Activada por ADN/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/análisis , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Radiación Ionizante , Transactivadores/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53
12.
Antimicrob Agents Chemother ; 58(7): 3927-33, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24777106

RESUMEN

Using an established nonhuman primate model, rhesus macaques were infected intravenously with a chimeric simian immunodeficiency virus (SIV) consisting of SIVmac239 with the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase from clone HXBc2 (RT-SHIV). The impacts of two enhanced (four- and five-drug) highly active antiretroviral therapies (HAART) on early viral decay and rebound were determined. The four-drug combination consisted of an integrase inhibitor, L-870-812 (L-812), together with a three-drug regimen comprising emtricitabine [(-)-FTC], tenofovir (TFV), and efavirenz (EFV). The five-drug combination consisted of one analog for each of the four DNA precursors {using TFV, (-)-FTC, (-)-ß-D-(2R,4R)-1,3-dioxolane-2,6-diaminopurine (amdoxovir [DAPD]), and zidovudine (AZT)}, together with EFV. A cohort treated with a three-drug combination of (-)-FTC, TFV, and EFV served as treated controls. Daily administration of a three-, four-, or five-drug combination of antiretroviral agents was initiated at week 6 or 8 after inoculation and continued up to week 50, followed by a rebound period. Plasma samples were collected routinely, and drug levels were monitored using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Viral loads were monitored with a standard TaqMan quantitative reverse transcriptase PCR (qRT-PCR) assay. Comprehensive analyses of replication dynamics were performed. RT-SHIV infection in rhesus macaques produced typical viral infection kinetics, with untreated controls establishing persistent viral loads of >10(4) copies of RNA/ml. RT-SHIV loads at the start of treatment (V0) were similar in all treated cohorts (P > 0.5). All antiretroviral drug levels were measureable in plasma. The four-drug and five-drug combination regimens (enhanced HAART) improved suppression of the viral load (within 1 week; P < 0.01) and had overall greater potency (P < 0.02) than the three-drug regimen (HAART). Moreover, rebound viremia occurred rapidly following cessation of any treatment. The enhanced HAART (four- or five-drug combination) showed significant improvement in viral suppression compared to the three-drug combination, but no combination was sufficient to eliminate viral reservoirs.


Asunto(s)
Terapia Antirretroviral Altamente Activa/métodos , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Animales , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/uso terapéutico , Combinación de Medicamentos , Cinética , Macaca mulatta , ARN Viral/sangre , Recurrencia , Virus de la Inmunodeficiencia de los Simios , Carga Viral
13.
Optom Vis Sci ; 91(3): 322-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24413276

RESUMEN

PURPOSE: To investigate the changes occurring in the axial length, choroidal thickness, and anterior biometrics of the eye during a 10-minute near task performed in downward gaze. METHODS: Twenty young adult subjects (10 emmetropes and 10 myopes) participated in this study. To measure ocular biometrics in downward gaze, an optical biometer was inclined on a custom-built height- and tilt-adjustable table. Baseline measures were collected after each subject performed a distance primary gaze control task for 10 minutes to provide washout period for previous visual tasks before each of three different accommodation/gaze conditions. These other three conditions included a near task (2.5 diopters [D]) in primary gaze and a near (2.5 D) and a far (0 D) accommodative task in downward gaze (25 degrees), all for 10 minutes' duration. Immediately after and then 5 and 10 minutes from the commencement of each trial, measurements of ocular biometrics (e.g., anterior biometrics, axial length, choroidal thickness, and retinal thickness) were obtained. RESULTS: Axial length increased with accommodation and was significantly greater for downward gaze with accommodation (mean ± SD change, 23 ± 13 µm at 10 minutes) compared with primary gaze with accommodation (8 ± 15 µm at 10 minutes) (p < 0.05). A small amount of choroidal thinning was also found during accommodation that was statistically significant in downward gaze (13 ± 14 µm at 10 minutes; p < 0.05). Accommodation in downward gaze also caused greater changes in anterior chamber depth and lens thickness compared with accommodation in primary gaze. CONCLUSIONS: Axial length, choroidal thickness, and anterior eye biometrics change significantly during accommodation in downward gaze as a function of time. These changes seem to be caused by the combined influence of biomechanical factors (i.e., extraocular muscle forces, ciliary muscle contraction) associated with near tasks in downward gaze.


Asunto(s)
Acomodación Ocular/fisiología , Longitud Axial del Ojo/patología , Miopía/fisiopatología , Adolescente , Adulto , Segmento Anterior del Ojo/patología , Fenómenos Biomecánicos , Biometría , Coroides/patología , Femenino , Humanos , Masculino , Retina/patología , Análisis y Desempeño de Tareas , Adulto Joven
14.
Antiviral Res ; 228: 105923, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38844175

RESUMEN

There are no approved vaccines or therapeutics for Lassa virus (LASV) infections. To identify compounds with anti-LASV activity, we conducted a cell-based screening campaign at biosafety level 4 and tested almost 60,000 compounds for activity against an infectious reporter LASV. Hits from this screen included several structurally related macrocycles. The most potent, Mac128, had a sub-micromolar EC50 against the reporter virus, inhibited wild-type clade IV LASV, and reduced viral titers by 4 orders of magnitude. Mechanistic studies suggested that Mac128 inhibited viral replication at the level of the polymerase.

15.
Access Microbiol ; 6(2)2024.
Artículo en Inglés | MEDLINE | ID: mdl-38482357

RESUMEN

Severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) is a novel human coronavirus that was identified in 2019. SARS-CoV-2 infection results in an acute, severe respiratory disease called coronavirus disease 2019 (COVID-19). The emergence and rapid spread of SARS-CoV-2 has led to a global public health crisis, which continues to affect populations across the globe. Real time reverse transcription polymerase chain reaction (rRT-PCR) is the reference standard test for COVID-19 diagnosis. Serological tests are valuable tools for serosurveillance programs and establishing correlates of protection from disease. This study evaluated the performance of one in-house enzyme linked immunosorbent assay (ELISA) utilizing the pre-fusion stabilized ectodomain of SARS-CoV-2 spike (S), two commercially available chemiluminescence assays Ortho VITROS Immunodiagnostic Products Anti-SARS-CoV-2 Total Reagent Pack and Abbott SARS-CoV-2 IgG assay and one commercially available Surrogate Virus Neutralization Test (sVNT), GenScript USA Inc., cPass SARS-CoV-2 Neutralization Antibody Detection Kit for the detection of SARS-CoV-2 specific antibodies. Using a panel of rRT-PCR confirmed COVID-19 patients' sera and a negative control group as a reference standard, all three immunoassays demonstrated high comparable positivity rates and low discordant rates. All three immunoassays were highly sensitive with estimated sensitivities ranging from 95.4-96.6 %. ROC curve analysis indicated that all three immunoassays had high diagnostic accuracies with area under the curve (AUC) values ranging from 0.9698 to 0.9807. High positive correlation was demonstrated among the conventional microneutralization test (MNT) titers and the sVNT inhibition percent values. Our study indicates that independent evaluations are necessary to optimize the overall utility and the interpretation of the results of serological tests. Overall, we demonstrate that all serological tests evaluated in this study are suitable for the detection of SARS-CoV-2 antibodies.

16.
Antiviral Res ; 214: 105619, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37142192

RESUMEN

Seoul virus (SEOV) is an emerging global health threat that can cause hemorrhagic fever with renal syndrome (HFRS), which results in case fatality rates of ∼2%. There are no approved treatments for SEOV infections. We developed a cell-based assay system to identify potential antiviral compounds for SEOV and generated additional assays to characterize the mode of action of any promising antivirals. To test if candidate antivirals targeted SEOV glycoprotein-mediated entry, we developed a recombinant reporter vesicular stomatitis virus expressing SEOV glycoproteins. To facilitate the identification of candidate antiviral compounds targeting viral transcription/replication, we successfully generated the first reported minigenome system for SEOV. This SEOV minigenome (SEOV-MG) screening assay will also serve as a prototype assay for discovery of small molecules inhibiting replication of other hantaviruses, including Andes and Sin Nombre viruses. Ours is a proof-of-concept study in which we tested several compounds previously reported to have activity against other negative-strand RNA viruses using our newly developed hantavirus antiviral screening systems. These systems can be used under lower biocontainment conditions than those needed for infectious viruses, and identified several compounds with robust anti-SEOV activity. Our findings have important implications for the development of anti-hantavirus therapeutics.


Asunto(s)
Infecciones por Hantavirus , Fiebre Hemorrágica con Síndrome Renal , Orthohantavirus , Virus Seoul , Humanos , Orthohantavirus/genética , Virus Seoul/genética , Seúl , Proteínas Recombinantes , Glicoproteínas , Vesiculovirus/genética
17.
Front Oncol ; 13: 1267650, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38239650

RESUMEN

Patients presenting with stage 4 ovarian carcinoma, including low-grade serous disease, have a poor prognosis. Although platinum-based therapies can offer some response, these therapies are associated with many side effects, and treatment resistance often develops. Toxic side effects along with disease progression render patients unable to receive additional lines of treatment and limit their options to hospice or palliative care. In this case report, we describe a patient with an unusual case of metastatic low-grade serous ovarian cancer with some features of high-grade disease who had received four previous lines of treatment and was suffering from atelectasis, pulmonary embolism, and hydronephrosis. A CLIA-certified drug sensitivity assay of an organoid culture derived from the patient's tumor (PARIS® test) identified several therapeutic options, including the combination of fulvestrant with everolimus. On this treatment regimen, the patient experienced 7 months of stable disease and survived nearly 11 months before succumbing to her disease. This case emphasizes the clinical utility of ex vivo drug testing as a new functional precision medicine approach to identify, in real-time, personalized treatment options for patients, especially those who are not benefiting from standard of care treatments.

18.
NPJ Precis Oncol ; 7(1): 45, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37202426

RESUMEN

Low-grade serous ovarian cancer (LGSOC) typically responds poorly to standard platinum-based chemotherapy and new therapeutic approaches are needed. We describe a remarkable response to targeted therapy in a patient with platinum-resistant, advanced LGSOC who had failed standard-of-care chemotherapy and two surgeries. The patient was in rapid decline and entering hospice care on home intravenous (i.v.) opioid analgesics and a malignant bowel obstruction requiring a G-tube. Genomic analysis of the patient's tumor did not indicate obvious therapeutic options. In contrast, a CLIA-certified drug sensitivity assay of an organoid culture derived from the patient's tumor identified several therapeutic choices, including Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, as well as the EGFR inhibitors afatinib and erlotinib. Following off-label administration of daily ibrutinib as monotherapy, the patient had an exceptional clinical turnaround over the following 65 weeks with normalization of CA-125 levels, resolution of the malignant bowel obstruction, halting of pain medications, and improvement of performance status from ECOG 3 to ECOG 1. After 65 weeks of stable disease, the patient's CA-125 levels began to rise, at which point the patient discontinued ibrutinib and began taking afatinib as monotherapy. The patient's CA-125 levels remained stable for an additional 38 weeks but due to anemia and rising CA-125 levels, the patient switched to erlotinib and is currently being monitored. This case highlights the clinical utility of ex vivo drug testing of patient-derived tumor organoids as a new functional precision medicine approach to identify effective personalized therapies for patients who have failed standard-of-care treatments.

19.
Mol Oncol ; 17(12): 2709-2727, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37533407

RESUMEN

Most patients with muscle-invasive bladder cancer (MIBC) are not cured with platinum chemotherapy. Up-regulation of nuclear factor kappa light-chain enhancer of activated B cells (NF-κB) is a major mechanism underlying chemoresistance, suggesting that its pharmacological inhibition may increase platinum efficacy. NF-κB signaling was investigated in two patient cohorts. The Cancer Genome Atlas (TCGA) was used to correlate NF-κB signaling and patient survival. The efficacy of cisplatin plus the NF-κB inhibitor dimethylaminoparthenolide (DMAPT) versus cisplatin or DMAPT alone was tested in vitro. Xenografted and immunocompetent MIBC mouse models were studied in vivo. Platinum-naive claudin-low MIBC showed constitutive NF-κB signaling and this was associated with reduced disease-specific survival in TCGA patients. Chemotherapy up-regulated NF-κB signaling and chemoresistance-associated genes, including SPHK1, PLAUR, and SERPINE1. In mice, DMAPT significantly improved the efficacy of cisplatin in both models. The combination preserved body weight, renal function, and morphology, reduced muscle fatigue and IL-6 serum levels, and did not aggravate immuno-hematological toxicity compared with cisplatin alone. These data provide a rationale for combining NF-κB inhibition with platinum-based chemotherapy and conducting a clinical trial in MIBC patients.


Asunto(s)
Antineoplásicos , Neoplasias de la Vejiga Urinaria , Humanos , Ratones , Animales , FN-kappa B/genética , Cisplatino/farmacología , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Músculos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
20.
Elife ; 112022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35758646

RESUMEN

During flight maneuvers, insects exhibit compensatory head movements which are essential for stabilizing the visual field on their retina, reducing motion blur, and supporting visual self-motion estimation. In Diptera, such head movements are mediated via visual feedback from their compound eyes that detect retinal slip, as well as rapid mechanosensory feedback from their halteres - the modified hindwings that sense the angular rates of body rotations. Because non-Dipteran insects lack halteres, it is not known if mechanosensory feedback about body rotations plays any role in their head stabilization response. Diverse non-Dipteran insects are known to rely on visual and antennal mechanosensory feedback for flight control. In hawkmoths, for instance, reduction of antennal mechanosensory feedback severely compromises their ability to control flight. Similarly, when the head movements of freely flying moths are restricted, their flight ability is also severely impaired. The role of compensatory head movements as well as multimodal feedback in insect flight raises an interesting question: in insects that lack halteres, what sensory cues are required for head stabilization? Here, we show that in the nocturnal hawkmoth Daphnis nerii, compensatory head movements are mediated by combined visual and antennal mechanosensory feedback. We subjected tethered moths to open-loop body roll rotations under different lighting conditions, and measured their ability to maintain head angle in the presence or absence of antennal mechanosensory feedback. Our study suggests that head stabilization in moths is mediated primarily by visual feedback during roll movements at lower frequencies, whereas antennal mechanosensory feedback is required when roll occurs at higher frequency. These findings are consistent with the hypothesis that control of head angle results from a multimodal feedback loop that integrates both visual and antennal mechanosensory feedback, albeit at different latencies. At adequate light levels, visual feedback is sufficient for head stabilization primarily at low frequencies of body roll. However, under dark conditions, antennal mechanosensory feedback is essential for the control of head movements at high frequencies of body roll.


Asunto(s)
Vuelo Animal , Mariposas Nocturnas , Animales , Retroalimentación , Retroalimentación Sensorial/fisiología , Vuelo Animal/fisiología , Movimientos de la Cabeza , Mariposas Nocturnas/fisiología
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