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1.
Phys Rev E ; 109(5-1): 054610, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38907434

RESUMO

We investigate experimentally the collective motion of polar vibrated disks in an annular geometry, varying both the packing fraction and the amplitude of the angular noise. For low enough noise and large enough density, an overall collective motion takes place along the tangential direction. The spatial organization of the flow reveals the presence of polar bands of large density, as expected from the commonly accepted picture of the transition to collective motion in systems of aligning polar active particles. However, in our case, the low density phase is also polar, consistent with what is observed when jamming takes place in a very high density flock. Interestingly, while in that case the particles in the high density bands are arrested, resulting in an upstream propagation at a constant speed, in our case the bands travel downstream with a density-dependent speed. We demonstrate from local measurements of the packing fraction, alignment, and flow speeds that the bands observed here result both from a polar ordering process and a motility induced phase separation mechanism.

2.
Plant Signal Behav ; 19(1): 2331894, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38516998

RESUMO

A bacterium growing on infected leaves of Hydrocotyle umbellata, commonly known as dollarweed, was isolated and identified as Pantoea ananatis. An ethyl acetate extract of tryptic soy broth (TSB) liquid culture filtrate of the bacterium was subjected to silica gel chromatography to isolate bioactive molecules. Indole was isolated as the major compound that gave a distinct, foul odor to the extract, together with phenethyl alcohol, phenol, tryptophol, N-acyl-homoserine lactone, 3-(methylthio)-1-propanol, cyclo(L-pro-L-tyr), and cyclo(dehydroAla-L-Leu). This is the first report of the isolation of cyclo(dehydroAla-L-Leu) from a Pantoea species. Even though tryptophol is an intermediate in the indoleacetic acid (IAA) pathway, we were unable to detect or isolate IAA. We investigated the effect of P. ananatis inoculum on the growth of plants. Treatment of Lemna paucicostata Hegelm plants with 4 × 109 colony forming units of P. ananatis stimulated their growth by ca. five-fold after 13 days. After 13 days of treatment, some control plants were browning, but treated plants were greener and no plants were browning. The growth of both Cucumis sativus (cucumber) and Sorghum bicolor (sorghum) plants was increased by ca. 20 to 40%, depending on the growth parameter and species, when the rhizosphere was treated with the bacterium after germination at the same concentration. Plant growth promotion by Pantoea ananatis could be due to the provision of the IAA precursor indole.


Assuntos
Álcoois , Centella , Indóis , Pantoea , Pantoea/química , Pantoea/metabolismo , Plantas/microbiologia
3.
Adv Mater ; 36(24): e2314367, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38532642

RESUMO

Broad size distributions and poor long-term colloidal stability of microRNA-carrying nanoparticles, especially those formed by polyelectrolyte complexation, represent major hurdles in realizing their clinical translation. Herein, peptide design is used alongside optimized flash nanocomplexation (FNC) to produce uniform peptide-based miRNA particles of exceptional stability that display anticancer activity against mesothelioma in vitro and in vivo. Modulating the content and display of lysine-based charge from small intrinsically disordered peptides used to complex miRNA proves essential in achieving stable colloids. FNC facilitates kinetic isolation of the mechanistic steps involved in particle formation to allow the preparation of particles of discrete size in a highly reproducible, scalable, and continuous manner, facilitating pre-clinical studies. To the best of the authors knowledge, this work represents the first example of employing FNC to prepare polyelectrolyte complexes of miRNA and peptide. Encapsulation of these particles into an injectable hydrogel matrix allows for their localized in vivo delivery by syringe. A one-time injection of a gel containing particles composed of miRNA-215-5p and the peptide PKM1 limits tumor progression in a xenograft model of mesothelioma.


Assuntos
Mesotelioma , MicroRNAs , Nanopartículas , Peptídeos , MicroRNAs/metabolismo , Nanopartículas/química , Humanos , Animais , Peptídeos/química , Linhagem Celular Tumoral , Camundongos , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Mesotelioma/metabolismo , Polieletrólitos/química , Cinética , Antineoplásicos/química , Antineoplásicos/farmacologia
4.
Angew Chem Int Ed Engl ; 63(4): e202313507, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38057633

RESUMO

Herein, peptide nucleic acids (PNAs) are employed in the design of a participatory duplex PNA-peptide crosslinking agent. Biophysical and mechanical studies show that crosslinkers present during peptide assembly leading to hydrogelation participate in the formation of fibrils while simultaneously installing crosslinks into the higher-order network that constitutes the peptide gel. The addition of 2 mol % crosslinker into the assembling system results in a ~100 % increase in mechanical stiffness without affecting the rate of peptide assembly or the local morphology of fibrils within the gel network. Stiffness enhancement is realized by only affecting change in the elastic component of the viscoelastic gel. A synthesis of the PNA-peptide duplex crosslinkers is provided that allows facile variation in peptide composition and addresses the notorious hydrophobic content of PNAs. This crosslinking system represents a new tool for modulating the mechanical properties of peptide-based hydrogels.


Assuntos
Ácidos Nucleicos Peptídicos , Ácidos Nucleicos Peptídicos/química , Peptídeos/química , Hidrogéis/química
5.
ACS Appl Mater Interfaces ; 15(23): 27560-27567, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37276244

RESUMO

Peptide sequence periodicity is a simple design tool that can be used to generate functional peptide-based surface coatings. De novo-designed peptide N3-PEG-VK16 is characterized by a hydrophobic periodicity of two that avidly binds to native polystyrene priming its surface for subsequent targeted functionalization via chemical ligation. The peptidic portion of N3-PEG-VK16 is responsible for surface binding, converting polystyrene's hydrophobic surface into a wettable and electrostatically charged environment that facilitates cell attachment. Native polystyrene surfaces are coated by simple peptide adsorption from an aqueous buffered solution, and the resulting primed surface is easily functionalized by cycloaddition chemistry. Herein, we show that ligating a vitronectin-derived peptide to primed polystyrene surfaces enables adhesion, expansion, long-term culture, and phenotype maintenance of human induced pluripotent stem cells. To demonstrate scope, we also show that additional functional ligands can be used, for example, nerve growth factor protein, to control neurite outgrowth.


Assuntos
Células-Tronco Pluripotentes Induzidas , Poliestirenos , Humanos , Poliestirenos/química , Adesão Celular , Peptídeos/farmacologia , Vitronectina/química , Propriedades de Superfície
6.
ACS Nano ; 17(11): 10651-10664, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37212741

RESUMO

A major challenge of cancer immunotherapy is to develop delivery strategies that can effectively and safely augment the immune system's antitumor response. Here, we report on the design and synthesis of a peptide-based supramolecular filament (SF) hydrogel as a universal carrier for localized delivery of three immunomodulating agents of distinct action mechanisms and different molecular weights, including an aPD1 antibody, an IL15 cytokine, and a STING agonist (CDA). We show that in situ hydrogelation can be triggered to occur upon intratumoral injection of SF solutions containing each of aPD1, IL15, or CDA. The formed hydrogel serves as a scaffold depot for sustained and MMP-2-responsive release of immunotherapeutic agents, achieving enhanced antitumor activities and reduced side effects. When administered in combination, the aPD1/IL15 or aPD1/CDA hydrogel led to substantially increased T-cell infiltration and prevented the development of adaptive immune resistance induced by IL15 or CDA alone. These immunotherapy combinations resulted in complete regression of established large GL-261 tumors in all mice and elicited a protective long-acting and systemic antitumor immunity to prevent tumor recurrence while eradicating distant tumors. We believe this SF hydrogel offers a simple yet generalizable strategy for local delivery of diverse immunomodulators for enhanced antitumoral response and improved treatment outcomes.


Assuntos
Hidrogéis , Interleucina-15 , Animais , Camundongos , Fatores Imunológicos , Imunoterapia/métodos , Citocinas , Adjuvantes Imunológicos , Linhagem Celular Tumoral
7.
Infect Immun ; 91(2): e0050022, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36715551

RESUMO

The peptidoglycan of Staphylococcus aureus is a critical cell envelope constituent and virulence factor that subverts host immune defenses and provides protection against environmental stressors. Peptidoglycan chains of the S. aureus cell wall are processed to characteristically short lengths by the glucosaminidase SagB. It is well established that peptidoglycan is an important pathogen-associated molecular pattern (PAMP) that is recognized by the host innate immune system and promotes production of proinflammatory cytokines, including interleukin-1ß (IL-1ß). However, how bacterial processing of peptidoglycan drives IL-1ß production is comparatively unexplored. Here, we tested the involvement of staphylococcal glucosaminidases in shaping innate immune responses and identified SagB as a mediator of IL-1ß production. A ΔsagB mutant fails to promote IL-1ß production by macrophages and dendritic cells, and processing of peptidoglycan by SagB is essential for this response. SagB-dependent IL-1ß production by macrophages is independent of canonical pattern recognition receptor engagement and NLRP3 inflammasome-mediated caspase activity. Instead, treatment of macrophages with heat-killed cells from a ΔsagB mutant leads to reduced caspase-independent cleavage of pro-IL-1ß, resulting in accumulation of the pro form in the macrophage cytosol. Furthermore, SagB is required for virulence in systemic infection and promotes IL-1ß production in a skin and soft tissue infection model. Taken together, our results suggest that the length of S. aureus cell wall glycan chains can drive IL-1ß production by innate immune cells through a previously undescribed mechanism related to IL-1ß maturation.


Assuntos
Peptidoglicano , Staphylococcus aureus , Hexosaminidases , Inflamassomos , Interleucina-1beta , Caspases , Parede Celular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Caspase 1
8.
Sci Adv ; 9(3): eadd0635, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36652514

RESUMO

Active matter, which includes crowds of organisms, is composed of constituents that independently consume and dissipate energy. Some active matter systems have been shown to sustain the propagation of various types of waves, resulting from the interplay between density and alignment. Here, we examine a type of solitary wave in dense two-dimensional columns of Solenopsis invicta, fire ants, in which the local activity, density and alignment all play a key role. We demonstrate that these waves are nonlinear and that they are composed of aligned ants that are constrained at the top by the time it takes disordered ants to activate and align and at the bottom by a density minimum enforced by gravity. Our results suggest that intrinsically switchable activity can be a productive framework to understand and trigger a broad range of wave-like behaviors, including stampedes in crowds and herds.

9.
Biomater Sci ; 11(2): 489-498, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36449365

RESUMO

The development of long-acting antiviral therapeutic delivery systems is crucial to improve the current treatment and prevention of HIV and chronic HBV. We report here on the conjugation of tenofovir (TFV), an FDA approved nucleotide reverse transcriptase inhibitor (NRTI), to rationally designed peptide amphiphiles (PAs), to construct antiviral prodrug hydrogelators (TFV-PAs). The resultant conjugates can self-assemble into one-dimensional nanostructures in aqueous environments and consequently undergo rapid gelation upon injection into 1× PBS solution to create a drug depot. The TFV-PA designs containing two or three valines could attain instantaneous gelation, with one displaying sustained release for more than 28 days in vitro. Our studies suggest that minor changes in peptide design can result in differences in supramolecular morphology and structural stability, which impacted in vitro gelation and release. We envision the use of this system as an important delivery platform for the sustained, linear release of TFV at rates that can be precisely tuned to attain therapeutically relevant TFV plasma concentrations.


Assuntos
Antivirais , Hidrogéis , Tenofovir/farmacologia , Adenina/farmacologia , Polímeros , Peptídeos
10.
Matter ; 6(2): 583-604, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36531610

RESUMO

Coronaviruses have historically precipitated global pandemics of severe acute respiratory syndrome (SARS) into devastating public health crises. Despite the virus's rapid rate of mutation, all SARS coronavirus 2 (SARS-CoV-2) variants are known to gain entry into host cells primarily through complexation with angiotensin-converting enzyme 2 (ACE2). Although ACE2 has potential as a druggable decoy to block viral entry, its clinical use is complicated by its essential biological role as a carboxypeptidase and hindered by its structural and chemical instability. Here we designed supramolecular filaments, called fACE2, that can silence ACE2's enzymatic activity and immobilize ACE2 to their surface through enzyme-substrate complexation. This docking strategy enables ACE2 to be effectively delivered in inhalable aerosols and improves its structural stability and functional preservation. fACE2 exhibits enhanced and prolonged inhibition of viral entry compared with ACE2 alone while mitigating lung injury in vivo.

11.
Nat Commun ; 13(1): 6710, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344501

RESUMO

Collections of fire ants are a form of active matter, as the ants use their internal metabolism to self-propel. In the absence of aligning interactions, theory and simulations predict that active matter with spatially dependent motility can undergo motility-induced phase separation. However, so far in experiments, the motility effects that drive this process have come from either crowding or an external parameter. Though fire ants are social insects that communicate and cooperate in nontrivial ways, we show that the effect of their interactions can also be understood within the framework of motility-induced phase separation. In this context, the slowing down of ants when they approach each other results in an effective attraction that can lead to space-filling clusters and an eventual formation of dynamical heterogeneities. These results illustrate that motility-induced phase separation can provide a unifying framework to rationalize the behavior of a wide variety of active matter systems.


Assuntos
Formigas , Venenos de Artrópodes , Animais , Interação Social , Aglomeração
12.
J Bacteriol ; 204(11): e0017522, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36314832

RESUMO

Streptococcus pyogenes, otherwise known as Group A Streptococcus (GAS), is an important and highly adaptable human pathogen with the ability to cause both superficial and severe diseases. Understanding how S. pyogenes senses and responds to its environment will likely aid in determining how it causes a breadth of diseases. One regulatory network involved in GAS's ability to sense and respond to the changing environment is the Rgg2/3 quorum sensing (QS) system, which responds to metal and carbohydrate availability and regulates changes to the bacterial surface. To better understand the impact of Rgg2/3 QS on S. pyogenes physiology, we performed RNA-seq and tandem mass tag (TMT)-LC-MS/MS analysis on cells in which this system was induced with short hydrophobic peptide (SHP) pheromone or disrupted. Primary findings confirmed that pheromone stimulation in wild-type cultures is limited to the induction of operons whose promoters contain previously determined Rgg2/3 binding sequences. However, a deletion mutant of rgg3, a strain that endogenously produces elevated amounts of pheromone, led to extended alterations of the transcriptome and proteome, ostensibly by stress-induced pathways. Under such exaggerated pheromone conditions, a connection was identified between Rgg2/3 and the stringent response. Mutation of relA, the bifunctional guanosine tetra- and penta-phosphate nucleoside synthetase/hydrolase, and alarmone synthase genes sasA and sasB, impacted culture doubling times and disabled induction of Rgg2/3 in response to mannose, while manipulation of Rgg2/3 signaling modestly altered nucleotide levels. Our findings indicate that excessive pheromone production or exposure places stress on GAS resulting in an indirect altered proteome and transcriptome beyond primary pheromone signaling. IMPORTANCE Streptococcus pyogenes causes several important human diseases. This study evaluates how the induction or disruption of a cell-cell communication system alters S. pyogenes's gene expression and, in extreme conditions, its physiology. Using transcriptomic and proteomic approaches, the results define the pheromone-dependent regulon of the Rgg2/3 quorum sensing system. In addition, we find that excessive pheromone stimulation, generated by genetic disruption of the Rgg2/3 system, leads to stress responses that are associated with the stringent response. Disruption of stringent response affects the ability of the cell-cell communication system to respond under normally inducing conditions. These findings assist in the determination of how S. pyogenes is impacted by and responds to nontraditional sources of stress.


Assuntos
Streptococcus pyogenes , Transcriptoma , Humanos , Streptococcus pyogenes/metabolismo , Proteômica , Proteoma/genética , Cromatografia Líquida , Transativadores/genética , Proteínas de Bactérias/metabolismo , Espectrometria de Massas em Tandem , Percepção de Quorum/genética , Feromônios/metabolismo , Regulação Bacteriana da Expressão Gênica
13.
Phys Rev E ; 106(1): L012604, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35974623

RESUMO

We study fire-ant columns, an active version of passive granular columns, and find that, despite the inherent activity of the ants and their natural tendency to rearrange, the ants develop force-chain structures that help support the weight of the column. Hence, the apparent mass at the bottom of the column saturates with added mass in a Janssen-like fashion, reminiscent of what is seen in passive-grain columns in wide containers. Activity-induced rearrangements within the column, however, lead to changes in the force-chain structure that slightly reduce the supportive nature of the force-chains over time and to fluctuations in the pressure at the bottom of the column that scale like the law of large numbers. We capture the experimental results in simulations that include not only friction with the walls, but also a fluctuating force that introduces activity and that effectively affects the force-chain structure of the ant collective.

14.
South Med J ; 115(6): 371-373, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35649522

RESUMO

OBJECTIVE: The coronavirus disease 2019 pandemic has produced an unprecedented amount of scientific research as well as a high number of article retractions. Social and news media have been used to disseminate scientific research, and this can include retracted or withdrawn research. This risks the persistence of low-quality research and may contribute to controversial ideas or conspiracy theories. METHODS: We examined 34 retracted or withdrawn coronavirus disease 2019 articles using alternative metrics. RESULTS: These articles continued to receive social and news media mentions up to 180 days postremoval, although most mentions occurred within 30 days postremoval. Articles available on preprint servers accounted for 45.5% of total mentions. CONCLUSIONS: A significant, positive correlation was observed among Scimago Journal Rank, Immediacy Index, and Journal Citation Index, and total article mentions.


Assuntos
COVID-19 , Humanos
15.
J Control Release ; 348: 1028-1049, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35752254

RESUMO

Peptides and peptide-based materials have an increasing role in the treatment of viral infections through their use as active pharmaceutical ingredients, targeting moieties, excipients, carriers, or structural components in drug delivery systems. The discovery of peptide-based therapeutic compounds, coupled with the development of new stabilization and formulation strategies, has led to a resurgence of antiviral peptide therapeutics over the past two decades. The ability of peptides to bind cell receptors and to facilitate membrane penetration and subsequent intracellular trafficking enables their use in various antiviral systems for improved targeting efficiency and treatment efficacy. Importantly, the self-assembly of peptides into well-defined nanostructures provides a vast library of discrete constructs and supramolecular biomaterials for systemic and local delivery of antiviral agents. We review here the recent progress in exploiting the therapeutic, biological, and self-assembling potential of peptides, peptide conjugates, and their supramolecular assemblies in treating human viral infections, with an emphasis on the treatment strategies for Human Immunodeficiency Virus (HIV).


Assuntos
Nanoestruturas , Viroses , Antivirais/uso terapêutico , Materiais Biocompatíveis/química , Humanos , Nanoestruturas/química , Peptídeos/química , Peptídeos/uso terapêutico , Viroses/tratamento farmacológico
16.
Nano Lett ; 22(10): 4182-4191, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35522052

RESUMO

Spraying serves as an attractive, minimally invasive means of administering hydrogels for localized delivery, particularly due to high-throughput deposition of therapeutic depots over an entire target site of uneven surfaces. However, it remains a great challenge to design systems capable of rapid gelation after shear-thinning during spraying and adhering to coated tissues in wet, physiological environments. We report here on the use of a collagen-binding peptide to enable a supramolecular design of a biocompatible, bioadhesive, and sprayable hydrogel for sustained release of therapeutics. After spraying, the designed peptide amphiphile-based supramolecular filaments exhibit fast, physical cross-linking under physiological conditions. Our ex vivo studies suggest that the hydrogelator strongly adheres to the wet surfaces of multiple organs, and the extent of binding to collagen influences release kinetics from the gel. We envision that the sprayable organ-adhesive hydrogel can serve to enhance the efficacy of incorporated therapeutics for many biomedical applications.


Assuntos
Sistemas de Liberação de Medicamentos , Hidrogéis , Hidrogéis/química , Peptídeos
17.
ACR Open Rheumatol ; 4(6): 486-491, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35157371

RESUMO

JOURNAL CLUB: Furie R, Khamashta M, Merrill JT, Werth VP, Kalunian K, Brohawn P, et al. Anifrolumab, an anti-interferon-α receptor monoclonal antibody, in moderate-to-severe systemic lupus erythematosus. Arthritis Rheumatol 2017;69:376-86. Objective To assess the efficacy and safety of anifrolumab, a type I interferon (IFN) receptor antagonist, in a phase IIb, randomized, double-blind, placebo-controlled study of adults with moderate-to-severe systemic lupus erythematosus (SLE). Methods Patients (n = 305) were randomized to receive intravenous anifrolumab (300 mg or 1,000 mg) or placebo, in addition to standard therapy, every 4 weeks for 48 weeks. Randomization was stratified by SLE Disease Activity Index 2000 score (<10 or ≥10), oral corticosteroid dosage (<10 or ≥10 mg/day), and type I IFN gene signature test status (high or low) based on a 4-gene expression assay. The primary end point was the percentage of patients achieving an SLE Responder Index (SRI [4]) response at week 24 with sustained reduction of oral corticosteroids (<10 mg/day and less than or equal to the dose at week 1 from week 12 through 24). Other end points (including SRI [4], British Isles Lupus Assessment Group [BILAG]-based Composite Lupus Assessment [BICLA], modified SRI [6], and major clinical response) were assessed at week 52. The primary end point was analyzed in the modified intent-to-treat (ITT) population and type I IFN-high subpopulation. The study result was considered positive if the primary end point was met in either of the 2 study populations. The Type I error rate was controlled at 0.10 (2-sided), within each of the 2 study populations for the primary end point analysis. Results The primary end point was met by more patients treated with anifrolumab (34.3% of 99 for 300 mg and 28.8% of 104 for 1,000 mg) than placebo (17.6% of 102) (P = 0.014 for 300 mg and P = 0.063 for 1,000 mg, versus placebo), with greater effect size in patients with a high IFN signature at baseline (13.2% in placebo-treated patients versus 36.0% [P = 0.004] and 28.2% [P = 0.029]) in patients treated with anifrolumab 300 mg and 1,000 mg, respectively. At week 52, patients treated with anifrolumab achieved greater responses in SRI(4) (40.2% versus 62.6% [P < 0.001] and 53.8% [P = 0.043] with placebo, anifrolumab 300 mg, and anifrolumab 1,000 mg, respectively), BICLA (25.7% versus 53.5% [P < 0.001] and 41.2% [P = 0.018], respectively), modified SRI(6) (28.4% versus 49.5% [P = 0.002] and 44.7% [P = 0.015], respectively), major clinical response (BILAG 2004 C or better in all organ domains from week 24 through week 52) (6.9% versus 19.2% [P = 0.012] and 17.3% [P = 0.025], respectively), and several other global and organ-specific end points. Herpes zoster was more frequent in the anifrolumab-treated patients (2.0% with placebo treatment versus 5.1% and 9.5% with anifrolumab 300 mg and 1,000 mg, respectively), as were cases reported as influenza (2.0% versus 6.1% and 7.6%, respectively), in the anifrolumab treatment groups. Incidence of serious adverse events was similar between groups (18.8% versus 16.2% and 17.1%, respectively). Conclusion Anifrolumab substantially reduced disease activity compared with placebo across multiple clinical end points in the patients with moderate-to-severe SLE. https://onlinelibrary.wiley.com/doi/10.1002/art.39962 Furie RA, Morand EF, Bruce IN, Manzi S, Kalunian KC, Vital EM, et al. Type I interferon inhibitor anifrolumab in active systemic lupus erythematosus (TULIP-1): a randomised, controlled, phase 3 trial. Lancet Rheumatol 2019;1:E208-19. Background Type I interferons are involved in systemic lupus erythematosus (SLE) pathogenesis. In a phase 2 trial, anifrolumab, a human monoclonal antibody to type I interferon receptor subunit 1, suppressed interferon gene signatures and substantially reduced SLE disease activity. Here, we sought to confirm the efficacy of anifrolumab versus placebo in a phase 3 trial of adult patients with SLE and moderate-to-severe disease activity despite standard-of-care treatment. Methods TULIP-1 was a double-blind, randomised, controlled, phase 3 trial done at 123 sites in 18 countries. Included patients were aged 18-70 years, with moderate-to-severe SLE, and ongoing stable treatment with either prednisone or equivalent, an antimalarial, azathioprine, mizoribine, mycophenolate mofetil or mycophenolic acid, or methotrexate. Patients were randomly assigned (2:1:2) to receive placebo, anifrolumab 150 mg, or anifrolumab 300 mg intravenously every 4 weeks for 48 weeks. Stable standard-of-care treatment continued except for mandatory attempts at oral corticosteroid tapering for patients receiving prednisone or equivalent of 10 mg/day or more at baseline. The primary outcome was the difference between the proportion of patients who achieved an SLE responder index-4 (SRI-4) response at week 52 with anifrolumab 300 mg versus with placebo. Key secondary outcomes were the difference between the anifrolumab 300 mg group and the placebo group in: proportion of patients in the interferon gene signature test-high subgroup who achieved SRI-4 at week 52; proportion of patients on 10 mg/day or more corticosteroids at baseline who achieved a sustained dose reduction to 7·5 mg/day or less from week 40 to 52; proportion of patients with a cutaneous lupus erythematosus disease area and severity index (CLASI) activity score of 10 or higher at baseline who achieved a 50% or more reduction in CLASI score by week 12; proportion of patients who achieved SRI-4 at week 24; and annualised flare rate through week 52. Other measures of disease activity were also assessed at week 52, including the British Isles Lupus Assessment Group-based composite lupus assessment (BICLA). Safety was also assessed. Efficacy and safety analyses were done in the population of patients who received at least one dose of study drug. This trial was registered at ClinicalTrials.gov (NCT02446912). Findings Between June 9, 2015, and June 16, 2017, 457 patients were randomly assigned to the anifrolumab 300 mg group (n = 180), the anifrolumab 150 mg group (n = 93), or the placebo group (n = 184). The proportion of patients at week 52 with an SRI-4 response was similar between anifrolumab 300 mg (65 [36%] of 180) and placebo (74 [40%] of 184; difference - 4·2 [95% CI -14·2 to 5·8], p = 0·41). Similarly, proportions of patients with an SRI-4 response at week 24, and at week 52 in patients in the interferon gene signature test-high subgroup, did not differ between the anifrolumab and placebo groups. In patients with baseline oral corticosteroids of at least 10 mg/day, sustained dose reduction to 7·5 mg/day or less was achieved by 42 (41%) of 103 patients in the anifrolumab 300 mg group and 33 (32%) of 102 patients in the placebo group (difference 8·9 [95% CI -4·1 to 21·9]). In patients with CLASI activity score of at least 10 at baseline, at least 50% reduction by week 12 was achieved by 24 (42%) of 58 patients in the anifrolumab 300 mg group and 14 (25%) of 54 in the placebo group (difference 17·0 [95% CI -0·3 to 34·3]). Annualised flare rates were 0·60 for anifrolumab and 0·72 for placebo (rate ratio 0·83 [95% CI 0·60 to 1·14]). BICLA response was achieved by 67 (37%) of 180 patients receiving anifrolumab 300 mg versus 49 (27%) of 184 receiving placebo (difference 10·1 [95% CI 0·6 to 19·7]). Anifrolumab's safety profile was similar to that observed in phase 2, with similar proportions of patients having a serious adverse event between groups (25 [14%] of 180 for anifrolumab 300 mg, ten [11%] of 93 for anifrolumab 150 mg, and 30 [16%] of 184 for placebo). Interpretation The primary endpoint was not reached. However, several secondary endpoints, including reduction in oral corticosteroid dose, CLASI responses, and BICLA responses, suggest clinical benefit of anifrolumab compared with placebo. Conclusive evidence for the efficacy of anifrolumab awaits further phase 3 trial data. Despite the inherent limitations of a 1-year phase 3 study, such as incomplete knowledge of applicability to the general population and scarce detection of rare safety signals, in addition to complications from prespecified restricted medication rules, our results suggest that anifrolumab might have the potential to provide a treatment option for patients who have active SLE while receiving standard therapy. Funding AstraZeneca. https://www.thelancet.com/journals/lanrhe/article/PIIS2665-9913(19)30076-1/fulltext Morand EF, Furie R, Tanaka Y, Bruce IN, Askanase AD, Richez C, et al. Trial of anifrolumab in active systemic lupus erythematosus. N Engl J Med 2020;382:211-21. Background Anifrolumab, a human monoclonal antibody to type I interferon receptor subunit 1 investigated for the treatment of systemic lupus erythematosus (SLE), did not have a significant effect on the primary end point in a previous phase 3 trial. The current phase 3 trial used a secondary end point from that trial as the primary end point. Methods We randomly assigned patients in a 1:1 ratio to receive intravenous anifrolumab (300 mg) or placebo every 4 weeks for 48 weeks. The primary end point of this trial was a response at week 52 defined with the use of the British Isles Lupus Assessment Group (BILAG)-based Composite Lupus Assessment (BICLA). A BICLA response requires reduction in any moderate-to-severe baseline disease activity and no worsening in any of nine organ systems in the BILAG index, no worsening on the Systemic Lupus Erythematosus Disease Activity Index, no increase of 0.3 points or more in the score on the Physician Global Assessment of disease activity (on a scale from 0 [no disease activity] to 3 [severe disease]), no discontinuation of the trial intervention, and no use of medications restricted by the protocol. Secondary end points included a BICLA response in patients with a high interferon gene signature at baseline; reductionsin the glucocorticoid dose, in the severity of skin disease, and in counts of swollen and tender joints; and the annualized flare rate. Results A total of 362 patients received the randomized intervention: 180 received anifrolumab and 182 received placebo. The percentage of patients who had a BICLA response was 47.8% in the anifrolumab group and 31.5% in the placebo group (difference, 16.3 percentage points; 95% confidence interval, 6.3 to 26.3; P = 0.001). Among patients with a high interferon gene signature, the percentage with a response was 48.0% in the anifrolumab group and 30.7% in the placebo group; among patients with a low interferon gene signature, the percentage was 46.7% and 35.5%, respectively. Secondary end points with respect to the glucocorticoid dose and the severity of skin disease, but not counts of swollen and tender joints and the annualized flare rate, also showed a significant benefit with anifrolumab. Herpes zoster and bronchitis occurred in 7.2% and 12.2% of the patients, respectively, who received anifrolumab. There was one death from pneumonia in the anifrolumab group. Conclusions Monthly administration of anifrolumab resulted in a higher percentage of patients with a response (as defined by a composite end point) at week 52 than did placebo, in contrast to the findings of a similar phase 3 trial involving patients with SLE that had a different primary end point. The frequency of herpes zoster was higher with anifrolumab than with placebo. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT02446899.) https://www.nejm.org/doi/full/10.1056/nejmoa1912196.

18.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35064089

RESUMO

Kasugamycin (KSG) is an aminoglycoside antibiotic widely used in agriculture and exhibits considerable medical potential. Previous studies suggested that KSG interferes with translation by blocking binding of canonical messenger RNA (mRNA) and initiator transfer tRNA (tRNA) to the small ribosomal subunit, thereby preventing initiation of protein synthesis. Here, by using genome-wide approaches, we show that KSG can interfere with translation even after the formation of the 70S initiation complex on mRNA, as the extent of KSG-mediated translation inhibition correlates with increased occupancy of start codons by 70S ribosomes. Even at saturating concentrations, KSG does not completely abolish translation, allowing for continuing expression of some Escherichia coli proteins. Differential action of KSG significantly depends on the nature of the mRNA residue immediately preceding the start codon, with guanine in this position being the most conducive to inhibition by the drug. In addition, the activity of KSG is attenuated by translational coupling as genes whose start codons overlap with the coding regions or the stop codons of the upstream cistrons tend to be less susceptible to drug-mediated inhibition. Altogether, our findings reveal KSG as an example of a small ribosomal subunit-targeting antibiotic with a well-pronounced context specificity of action.


Assuntos
Aminoglicosídeos/farmacologia , Sítios de Ligação , Iniciação Traducional da Cadeia Peptídica/efeitos dos fármacos , RNA Mensageiro/genética , Ribossomos/metabolismo , Aminoglicosídeos/química , Códon de Iniciação , Estrutura Molecular , Fases de Leitura Aberta , Ligação Proteica , Biossíntese de Proteínas/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Ribossomos/química , Relação Estrutura-Atividade
19.
Proc (Bayl Univ Med Cent) ; 35(1): 43-45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34970030

RESUMO

Alternative metrics are unique bibliometrics comprising social, news, and other sources of media outside of traditional academic citations. Some have suggested that these metrics can complement traditional metrics of research impact, including public engagement with research. The COVID-19 pandemic provides a unique opportunity to study alternative metrics and the dissemination of scientific research given the heightened academic and public interest. This study analyzed Altmetric Attention Scores for the top 25 publications on COVID-19 and the top 25 non-COVID-19 publications in 2020. There were significantly higher levels of social attention scores across multiple metrics for COVID-19 articles than for non-COVID-19 articles for that year. There was a slightly higher goodness of fit between Altmetric Attention Scores and academic citations for COVID-19 publications than for non-COVID-19 publications, although trendline differences were not significant. These results suggest that researchers should be aware that their studies can become highly visible on publicly available social and news media platforms, especially during events of high interest (such as a global pandemic).

20.
Phys Rev E ; 106(6-1): 064606, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36671158

RESUMO

The configurations taken by polymers embedded in out-of-equilibrium baths may have broad implications in a variety of biological systems. As such, they have attracted considerable interest, particularly in simulation studies. Here we analyze the distribution of configurations taken by a passive flexible chain in a bath of hard, self-propelled, vibrated disks and systematically compare it to that of the same flexible chain in a bath of hard, thermal-like, vibrated disks. We demonstrate experimentally that the mean length and mean radius of gyration of both chains agree with Flory's law. However, the Kuhn length associated with the number of correlated monomers is smaller in the case of the active bath, corresponding to a higher effective temperature. Importantly, the active bath does not just simply map on a hot equilibrium bath. Close examination of the chains' configurations indicates a marked bias, with the chain in the active bath more likely assuming configurations with a single prominent bend.


Assuntos
Polímeros , Simulação por Computador
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