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1.
Artículo en Inglés | MEDLINE | ID: mdl-38878020

RESUMEN

BACKGROUND: Biologic therapies inhibiting the IL-4 or IL-5 pathways are very effective in the treatment of asthma and other related conditions. However, the cytokines IL-4 and IL-5 also play a role in the generation of adaptive immune responses. Although these biologics do not cause overt immunosuppression, their effect in primary severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunization has not been studied completely. OBJECTIVE: Our aim was to evaluate the antibody and cellular immunity after SARS-CoV-2 mRNA vaccination in patients on biologics (PoBs). METHODS: Patients with severe asthma or atopic dermatitis who were taking benralizumab, dupilumab, or mepolizumab and had received the initial dose of the 2-dose adult SARS-CoV-2 mRNA vaccine were enrolled in a prospective, observational study. As our control group, we used a cohort of immunologically healthy subjects (with no significant immunosuppression) who were not taking biologics (NBs). We used a multiplexed immunoassay to measure antibody levels, neutralization assays to assess antibody function, and flow cytometry to quantitate Spike-specific lymphocytes. RESULTS: We analyzed blood from 57 patients in the PoB group and 46 control subjects from the NB group. The patients in the PoB group had lower levels of SARS-CoV-2 antibodies, pseudovirus neutralization, live virus neutralization, and frequencies of Spike-specific B and CD8 T cells at 6 months after vaccination. In subgroup analyses, patients with asthma who were taking biologics had significantly lower pseudovirus neutralization than did subjects with asthma who were not taking biologics. CONCLUSION: The patients in the PoB group had reduced SARS-CoV-2-specific antibody titers, neutralizing activity, and virus-specific B- and CD8 T-cell counts. These results have implications when considering development of a more individualized immunization strategy in patients who receive biologic medications blocking IL-4 or IL-5 pathways.

2.
Respir Med Res ; 86: 101107, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38843603

RESUMEN

BACKGROUND: Nebulized Hypertonic saline (HS) and positive expiratory pressure device (PEP) are often used in patients with bronchiectasis. We sought to describe the clinical characteristics in patients using HS and PEP, utilizing a large national database registry. METHODS: Data from the US Bronchiectasis and NTM Research Registry were used in this study. Patients with a diagnosis of bronchiectasis were included. Eligible patients were assigned to one of four mutually exclusive groups: HS only, PEP only, HS & PEP, or no airway clearance or mucoactive agent. Descriptive statistics were computed for the overall study population and stratified by the four groups. One-way ANOVA and chi-square tests were used to test the difference in the means in continuous variables and the association between categorical variables (respectively) across the four groups. RESULTS: A total of 2195 patients were included. Of those with bronchiectasis and a productive cough, a greater number of patients utilized HS only vs PEP only (17.5 % vs 9.1 %, p < 0.001). Similar association was found in those with Pseudomonas aeruginosa (22.3 % HS only vs 6.5 % PEP only, p < 0.001). There was a higher number of patients who used HS and PEP therapy in combination vs PEP therapy alone (25.0 % vs 9.1 %, p = 0.002), in those with a productive cough. CONCLUSIONS: In patients with bronchiectasis and a productive cough or Pseudomonas aeruginosa, HS is used more often than PEP alone. There is a need for further analysis to compare these two modalities and explore the factors influencing their utilization.

4.
Isr J Chem ; 63(3-4)2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38046285

RESUMEN

Functional regulation of cell signaling through dynamic changes in protein activity state as well as spatial organization represent two dynamic, complex, and conserved phenomena in biology. Seemingly separate areas of -omics method development have focused on building tools that can detect and quantify protein activity states, as well as map sub-cellular and intercellular protein organization. Integration of these efforts, through the development of chemical tools and platforms that enable detection and quantification of protein functional states with spatial resolution provide opportunities to better understand heterogeneity in the proteome within cell organelles, multi-cellular tissues, and whole organisms. This review provides an overview of and considerations for major classes of chemical proteomic probes and technologies that enable protein activity mapping from sub-cellular compartments to live animals.

5.
ACS Omega ; 8(40): 37442-37450, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37841192

RESUMEN

Nucleic acids and proteins possess encoded "languages" that can be used for information storage or to direct function. However, each biopolymer is limited to encoding its respective "language." Using a peptide nucleic acid (PNA) scaffold, nucleobase and amino acid residues can be installed on a singular backbone, enabling a single biopolymer to encode both languages. Our laboratory previously reported the development of a "bilingual" PNA biopolymer that incorporates a sequence-specific nucleic acid code interspersed with hydrophobic (alanine) and hydrophilic (lysine) amino acid residues at defined positions to produce amphiphilic character. We observed the amphiphilic amino acid residues directing the biopolymer to undergo self-assembly into micelle-like structures, while the nucleic acid recognition was harnessed for disassembly. Herein, we report a series of bilingual PNA sequences having amino acid residues with varying lengths, functional group charges, hydrophobicities, and spacings to elucidate the effect of these parameters on micelle assembly and nucleic acid recognition. Negative charges in the hydrophilic block or increased bulkiness of the hydrophobic side chains led to assembly into similarly sized micelles; however, the negative charge additionally led to increased critical micelle concentration. Upon PNA sequence truncation to decrease the spacing between side chains, the biopolymers remained capable of self-assembling but formed smaller structures. Characterization of disassembly revealed that each variant retained sequence recognition capabilities and stimuli-responsive disassembly. Together, these data show that the amino acid and nucleic acid sequences of amphiphilic bilingual biopolymers can be customized to finely tune the assembly and disassembly properties, which has implications for applications such as the encapsulation and delivery of cargo for therapeutics.

6.
Pulm Pharmacol Ther ; 83: 102260, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37741357

RESUMEN

RATIONALE: Longitudinal epidemiological and clinical data are needed to improve the management of patients with bronchiectasis developing nontuberculous mycobacterial (NTM) pulmonary disease. OBJECTIVES: To describe the epidemiology, patient management, and treatment outcomes of NTM infections in patients with bronchiectasis enrolled in the United States Bronchiectasis and NTM Research Registry (US BRR). METHODS: This was a retrospective cohort study of patients with bronchiectasis and NTM infections enrolled with follow-up in the US BRR in 2008-2019. The study included patients with ≥1 positive NTM respiratory culture in the 24-month baseline period (baseline NTM cohort) and/or during the annual follow-up visits (incident NTM cohort). Incidence, prevalence, baseline patient characteristics, treatment exposure, treatment outcomes, and respiratory clinical outcomes were described in the baseline NTM cohort, incident NTM cohort, and both cohorts combined (prevalent NTM cohort). RESULTS: Between 2008 and 2019, 37.9% (1457/3840) of patients with bronchiectasis in the US BRR met the inclusion criteria for this study and were reported to have Mycobacterium avium complex (MAC) and/or Mycobacterium abscessus complex (MABSC) infections. MAC prevalence increased steadily in the US BRR during 2009-2019; incidence was relatively stable, except for a peak in 2011 followed by a slow decrease. MABSC and mixed MAC/MABSC infections were rare. Most patients with bronchiectasis and NTM infections in the registry were female, White, and aged >65 years. The antibiotics administered most commonly reflected current guidelines. In the prevalent cohort, 44.9% of MAC infections and 37.1% of MABSC infections remained untreated during follow-up, and MAC treatment was initiated with delay (>90 days after positive NTM respiratory culture) twice as frequently as promptly (≤90 days after positive NTM respiratory culture) (68.6% vs 31.4%, respectively). The median time from diagnosis to treatment was shorter for MABSC versus MAC infections (194.0 days [interquartile range (IQR) 8.0, 380.0] vs 296.0 days [IQR 35.0, 705.0], respectively). Among patients with MAC infections who completed treatment, 27.6% were classified as cured and 29.6% as treatment failure during the annual follow-up visit window. For MABSC, these proportions were 25.0% and 28.0%, respectively. CONCLUSIONS: A considerable proportion of MAC and MABSC infections were untreated or treated after initial delay/observation. MABSC infections were more likely to be treated and start treatment sooner than MAC infections. Further longitudinal studies are warranted to evaluate the monitor-with-delay approach and inform clinical guidelines.


Asunto(s)
Bronquiectasia , Infecciones por Mycobacterium no Tuberculosas , Humanos , Femenino , Masculino , Estudios Retrospectivos , Estudios de Cohortes , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas , Complejo Mycobacterium avium , Bronquiectasia/tratamiento farmacológico , Bronquiectasia/epidemiología , Bronquiectasia/microbiología , Sistema de Registros
7.
ACS Omega ; 8(1): 238-248, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36643573

RESUMEN

The deamination of adenosine to inosine is an important modification in nucleic acids that functionally recodes the identity of the nucleobase to a guanosine. Current methods to analyze and detect this single nucleotide change, such as sequencing and PCR, typically require time-consuming or costly procedures. Alternatively, fluorescent "turn-on" probes that result in signal enhancement in the presence of target are useful tools for real-time detection and monitoring of nucleic acid modification. Here we describe forced-intercalation PNA (FIT-PNA) probes that are designed to bind to inosine-containing nucleic acids and use thiazole orange (TO), 4-dimethylamino-naphthalimide (4DMN), and malachite green (MG) fluorogenic dyes to detect A-to-I editing events. We show that incorporation of the dye as a surrogate base negatively affects the duplex stability but does not abolish binding to targets. We then determined that the identity of the adjacent nucleobase and temperature affect the overall signal and fluorescence enhancement in the presence of inosine, achieving an 11-fold increase, with a limit of detection (LOD) of 30 pM. We determine that TO and 4DMN probes are viable candidates to enable selective inosine detection for biological applications.

8.
Nat Biotechnol ; 41(4): 541-551, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36302987

RESUMEN

Despite unequivocal roles in disease, transcription factors (TFs) remain largely untapped as pharmacologic targets due to the challenges in targeting protein-protein and protein-DNA interactions. Here we report a chemical strategy to generate modular synthetic transcriptional repressors (STRs) derived from the bHLH domain of MAX. Our synthetic approach yields chemically stabilized tertiary domain mimetics that cooperatively bind the MYC/MAX consensus E-box motif with nanomolar affinity, exhibit specificity that is equivalent to or beyond that of full-length TFs and directly compete with MYC/MAX protein for DNA binding. A lead STR directly inhibits MYC binding in cells, downregulates MYC-dependent expression programs at the proteome level and inhibits MYC-dependent cell proliferation. Co-crystallization and structure determination of a STR:E-box DNA complex confirms retention of DNA recognition in a near identical manner as full-length bHLH TFs. We additionally demonstrate structure-blind design of STRs derived from alternative bHLH-TFs, confirming that STRs can be used to develop highly specific mimetics of TFs targeting other gene regulatory elements.


Asunto(s)
Proteínas Proto-Oncogénicas c-myc , Factores de Transcripción , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/química , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factores de Transcripción/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Secuencias Hélice-Asa-Hélice , Secuencias Reguladoras de Ácidos Nucleicos , ADN/genética , ADN/metabolismo
9.
RSC Chem Biol ; 3(8): 1035-1043, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35974999

RESUMEN

Peptide nucleic acids (PNAs) are high-affinity synthetic nucleic acid analogs capable of hybridization with native nucleic acids. PNAs synthesized having amino acid sidechains installed at the γ-position along the backbone provide a template for a single biopolymer to simultaneously encode nucleic acid and amino acid sequences. Previously, we reported the development of "bilingual" PNAs through the synthesis of an amphiphilic sequence featuring separate blocks of hydrophobic and hydrophilic amino acid functional groups. These PNAs combined the sequence-specific binding activity of nucleic acids with the structural organization properties of peptides. Like other amphiphilic compounds, these γ-PNAs were observed to assemble spontaneously into micelle-like nanostructures in aqueous solutions and disassembly was induced through hybridization to a complementary sequence. Here, we explore whether assembly of these bilingual PNAs is possible by harnessing the nucleic acid code. Specifically, we designed an amphiphile-masking duplex system in which spontaneous amphiphile assembly is prevented through hybridization to a nucleic acid masking sequence. We show that the amphiphile is displaced upon introduction of a releasing sequence complementary to the masking sequence through toehold mediated displacement. Upon release, we observe that the amphiphile proceeds to assemble in a fashion consistent with our previously reported structures. Our approach represents a novel method for controlled stimuli-responsive assembly of PNA-based nanostructures.

10.
Chest ; 160(3): e316-e317, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34488977
11.
RSC Chem Biol ; 2(4): 1249-1256, 2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34458838

RESUMEN

Peptide nucleic acid (PNA) is a unique synthetic nucleic acid analog that has been adopted for use in many biological applications. These applications rely upon the robust Franklin-Watson-Crick base pairing provided by PNA, particularly at lower ionic strengths. However, our understanding of the relationship between the kinetics of PNA:DNA hybridization and ionic strength is incomplete. Here we measured the kinetics of association and dissociation of PNA with DNA across a range of ionic strengths and temperatures at single-molecule resolution using total internal reflection fluorescence imaging. Unlike DNA:DNA duplexes, PNA:DNA duplexes are more stable at lower ionic strength, and we demonstrate that this is due to a higher association rate. While the dissociation rate of PNA:DNA duplexes is largely insensitive to ionic strength, it is significantly lower than that of DNA:DNA duplexes having the same number and sequence of base pairing interactions. The temperature dependence of PNA:DNA kinetic rate constants indicate a significant enthalpy barrier to duplex dissociation, and to a lesser extent, duplex formation. This investigation into the kinetics of PNA:DNA hybridization provides a framework towards better understanding and design of PNA sequences for future applications.

12.
J Am Chem Soc ; 142(41): 17766-17781, 2020 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-33017148

RESUMEN

Controlling the structure and activity of nucleic acids dramatically expands their potential for application in therapeutics, biosensing, nanotechnology, and biocomputing. Several methods have been developed to impart responsiveness of DNA and RNA to small-molecule and light-based stimuli. However, heat-triggered control of nucleic acids has remained largely unexplored, leaving a significant gap in responsive nucleic acid technology. Moreover, current technologies have been limited to natural nucleic acids and are often incompatible with polymerase-generated sequences. Here we show that glyoxal, a well-characterized compound that covalently attaches to the Watson-Crick-Franklin face of several nucleobases, addresses these limitations by thermoreversibly modulating the structure and activity of virtually any nucleic acid scaffold. Using a variety of DNA and RNA constructs, we demonstrate that glyoxal modification is easily installed and potently disrupts nucleic acid structure and function. We also characterize the kinetics of decaging and show that activity can be restored via tunable thermal removal of glyoxal adducts under a variety of conditions. We further illustrate the versatility of this approach by reversibly caging a 2'-O-methylated RNA aptamer as well as synthetic threose nucleic acid (TNA) and peptide nucleic acid (PNA) scaffolds. Glyoxal caging can also be used to reversibly disrupt enzyme-nucleic acid interactions, and we show that caging of guide RNA allows for tunable and reversible control over CRISPR-Cas9 activity. We also demonstrate glyoxal caging as an effective method for enhancing PCR specificity, and we cage a biostable antisense oligonucleotide for time-release activation and titration of gene expression in living cells. Together, glyoxalation is a straightforward and scarless method for imparting reversible thermal responsiveness to theoretically any nucleic acid architecture, addressing a significant need in synthetic biology and offering a versatile new tool for constructing programmable nucleic acid components in medicine, nanotechnology, and biocomputing.


Asunto(s)
Glioxal/química , Ácidos Nucleicos/química , Secuencia de Bases , Catálisis , Dominio Catalítico , Metilación , Conformación de Ácido Nucleico , Oligonucleótidos/química , Ácidos Nucleicos de Péptidos/química , Relación Estructura-Actividad , Biología Sintética , Tetrosas/química , Termodinámica
13.
Chemistry ; 26(44): 9874-9878, 2020 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-32428320

RESUMEN

Straightforward methods for detecting adenosine-to-inosine (A-to-I) RNA editing are key to a better understanding of its regulation, function, and connection with disease. We address this need by developing a novel reagent, N-(4-ethynylphenyl)acrylamide (EPhAA), and illustrating its ability to selectively label inosine in RNA. EPhAA is synthesized in a single step, reacts rapidly with inosine, and is "click"-compatible, enabling flexible attachment of fluorescent probes at editing sites. We first validate EPhAA reactivity and selectivity for inosine in both ribonucleosides and RNA substrates, and then apply our approach to directly monitor in vitro A-to-I RNA editing activity using recombinant ADAR enzymes. This method improves upon existing inosine chemical-labeling techniques and provides a cost-effective, rapid, and non-radioactive approach for detecting inosine formation in RNA. We envision this method will improve the study of A-to-I editing and enable better characterization of RNA modification patterns in different settings.


Asunto(s)
Acrilamida/química , Adenosina/análisis , Química Clic , Inosina/análisis , Edición de ARN , ARN/química , ARN/metabolismo , Adenosina/metabolismo , Inosina/metabolismo
14.
Open Forum Infect Dis ; 7(4): ofaa079, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32322600

RESUMEN

Patients with Mycobacterium avium complex lung disease treated with amikacin liposome inhalation suspension (ALIS) at 2 clinics in the United States were surveyed to assess the frequency and management of ALIS-associated respiratory adverse events. Most respondents experienced these events, but management through physician-guided measures (eg, bronchodilator use, oral rinses, and/or temporary dosing adjustments) resulted in symptomatic improvement.

15.
Chem Commun (Camb) ; 56(13): 1926-1935, 2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32009137

RESUMEN

Nature encodes the information required for life in two fundamental biopolymers: nucleic acids and proteins. Peptide nucleic acid (PNA), a synthetic analog comprised of nucleobases arrayed along a pseudopeptide backbone, has the ability to combine the power of nucleic acids to encode information with the versatility of amino acids to encode structure and function. Historically, PNA has been perceived as a simple nucleic acid mimic having desirable properties such as high biostability and strong affinity for complementary nucleic acids. In this feature article, we aim to adjust this perception by highlighting the ability of PNA to act as a peptide mimic and showing the largely untapped potential to encode information in the amino acid sequence. First, we provide an introduction to PNA and discuss the use of conjugation to impart tunable properties to the biopolymer. Next, we describe the integration of functional groups directly into the PNA backbone to impart specific physical properties. Lastly, we highlight the use of these integrated amino acid side chains to encode peptide-like sequences in the PNA backbone, imparting novel activity and function and demonstrating the ability of PNA to simultaneously mimic both a peptide and a nucleic acid.


Asunto(s)
Ácidos Nucleicos de Péptidos/química , Interacciones Hidrofóbicas e Hidrofílicas , Hibridación de Ácido Nucleico , Péptidos/química
17.
ATS Sch ; 1(4): 416-435, 2020 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-33870311

RESUMEN

The American Thoracic Society Core Curriculum updates clinicians annually in adult and pediatric pulmonary disease, medical critical care, and sleep medicine in a 3- to 4-year recurring cycle of topics. The topics of the 2020 Pulmonary Core Curriculum include pulmonary vascular disease (submassive pulmonary embolism, chronic thromboembolic pulmonary hypertension, and pulmonary hypertension) and pulmonary infections (community-acquired pneumonia, pulmonary nontuberculous mycobacteria, opportunistic infections in immunocompromised hosts, and coronavirus disease [COVID-19]).

19.
J Am Chem Soc ; 141(48): 19038-19047, 2019 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-31711285

RESUMEN

Nucleic acids and proteins are the fundamental biopolymers that support all life on Earth. Nucleic acids store large amounts of information in nucleobase sequences while peptides and proteins utilize diverse amino acid functional groups to adopt complex structures and perform wide-ranging activities. Although nature has evolved machinery to read the nucleic acid code and translate it into amino acid code, the extant biopolymers are restricted to encoding amino acid or nucleotide sequences separately, limiting their potential applications in medicine and biotechnology. Here we describe the design, synthesis, and stimuli-responsive assembly behavior of a bilingual biopolymer that integrates both amino acid and nucleobase sequences into a single peptide nucleic acid (PNA) scaffold to enable tunable storage and retrieval of tertiary structural behavior and programmable molecular recognition capabilities. Incorporation of a defined sequence of amino acid side-chains along the PNA backbone yields amphiphiles having a "protein code" that directs self-assembly into micellar architectures in aqueous conditions. However, these amphiphiles also carry a "nucleotide code" such that subsequent introduction of a complementary RNA strand induces a sequence-specific disruption of assemblies through hybridization. Together, these properties establish bilingual PNA as a powerful biopolymer that combines two information systems to harness structural responsiveness and sequence recognition. The PNA scaffold and our synthetic system are highly generalizable, enabling fabrication of a wide array of user-defined peptide and nucleotide sequence combinations for diverse future biomedical and nanotechnology applications.


Asunto(s)
Ácidos Nucleicos/genética , Ácidos Nucleicos de Péptidos/genética , Proteínas/genética , Secuencia de Bases , Código Genético , Conformación de Ácido Nucleico , Hibridación de Ácido Nucleico , Ácidos Nucleicos/síntesis química , Ácidos Nucleicos/química , Ácidos Nucleicos de Péptidos/síntesis química , Ácidos Nucleicos de Péptidos/química , Tensoactivos/síntesis química , Tensoactivos/química
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