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1.
PLoS Biol ; 22(1): e3002089, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236818

RESUMO

Viral respiratory infections are an important public health concern due to their prevalence, transmissibility, and potential to cause serious disease. Disease severity is the product of several factors beyond the presence of the infectious agent, including specific host immune responses, host genetic makeup, and bacterial coinfections. To understand these interactions within natural infections, we designed a longitudinal cohort study actively surveilling respiratory viruses over the course of 19 months (2016 to 2018) in a diverse cohort in New York City. We integrated the molecular characterization of 800+ nasopharyngeal samples with clinical data from 104 participants. Transcriptomic data enabled the identification of respiratory pathogens in nasopharyngeal samples, the characterization of markers of immune response, the identification of signatures associated with symptom severity, individual viruses, and bacterial coinfections. Specific results include a rapid restoration of baseline conditions after infection, significant transcriptomic differences between symptomatic and asymptomatic infections, and qualitatively similar responses across different viruses. We created an interactive computational resource (Virome Data Explorer) to facilitate access to the data and visualization of analytical results.


Assuntos
Coinfecção , Viroses , Vírus , Humanos , Coinfecção/genética , Viroma , Estudos Longitudinais , Vírus/genética , Viroses/genética , Viroses/epidemiologia , Bactérias/genética , Perfilação da Expressão Gênica
2.
AIDS Behav ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801501

RESUMO

With the rise of new and emerging Pre-Exposure Prophylaxis (PrEP) modalities, greater attention is needed to better understand how people who could benefit from PrEP make decisions to initiate, stop, pause, or switch PrEP regimens. In this study we borrow from the field of consumer research to create a consumer-derived PrEP Consumer Journey Model that describes key decision-making touchpoints a PrEP consumer moves through within and outside of a clinical context. Using in-depth interviews (n = 29) with gay and bisexual men who have sex with men, we evaluate which system 1 (emotional) and system 2 (cognitive) attributes are used for decision-making at different touchpoints along the PrEP Consumer Journey. Our results suggest system 1 attributes, such as feeling protected, reducing anxiety, enhancing pleasure, social norms, and taking ownership over health were more salient when consumers moved from pre-contemplation to information gathering, as well as evaluating post-uptake experience. System 2 attributes, including cost, side effects, dosing schedule, and sexual frequency, were present throughout the PrEP Consumer Journey, but particularly influential in the information gathering stage and when pausing, switching, or opting out of PrEP. We contend the PrEP Consumer Journey, and our findings related to decision-making, can help orient medical providers to anticipated patient concerns around PrEP use and ultimately provide more supportive and engaging PrEP counseling and services.

3.
Opt Express ; 31(16): 26378-26382, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710500

RESUMO

Homodyne detection is a common self-referenced technique to extract optical quadratures. Due to ubiquitous fluctuations, experiments measuring optical quadratures require homodyne angle control. Current homodyne angle locking techniques only provide high quality error signals in a span significantly smaller than π radians, the span required for full state tomography, leading to inevitable discontinuities during full tomography. Here, we present and demonstrate a locking technique using a universally tunable modulator which produces high quality error signals at an arbitrary homodyne angle. Our work enables continuous full-state tomography and paves the way to backaction evasion protocols based on a time-varying homodyne angle.

4.
AIDS Behav ; 27(3): 823-831, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36044125

RESUMO

With the recent endorsement of PrEP by the Chinese government, research is urgently needed to better understand factors impacting PrEP uptake among gay, bisexual, and other men who have sex with men (GBMSM) in China. This study examined willingness to use PrEP for HIV prevention among GBMSM in China through structural equation modeling. We examined the relationship among PrEP-related attitudes, subjective norms, PrEP-related knowledge and beliefs about medicines and willingness to use PrEP. The analysis showed a good fit between the data and both the measurement model (RMSEA = 0.060) and structural model (RMSEA = 0.054). Knowledge, attitudes, and subjective norms were significantly related to intention to use PrEP, whereas the effect of general beliefs about medicines was insignificant. These effect mechanisms point to the importance of designing interventions to support PrEP uptake that target knowledge, enhance positive attitudes about PrEP within social networks, and build positive social norms around PrEP among sexually active GBMSM.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Análise de Classes Latentes , Infecções por HIV/prevenção & controle , China
5.
Endocr Pract ; 28(2): 165-172, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34763071

RESUMO

OBJECTIVE: We compared the efficacy of the second-generation basal insulin degludec (IDeg) to that of insulin aspart via pump using continuous glucose monitoring in patients with well-controlled type 1 diabetes. METHODS: In this 40-week, single-center, randomized, crossover-controlled trial, adults with well-controlled type 1 diabetes (hemoglobin A1C of <7.5% [<58 mmol/mol]) (N = 52) who were using an insulin pump and continuous glucose monitoring were randomized to 1 of 2 treatments for a 20-week period: a single daily injection of IDeg with bolus aspart via pump or a continuous subcutaneous insulin infusion (CSII) with aspart, followed by crossover to the other treatment. The primary endpoint was time in range (70-180 mg/dL) during the final 2 weeks of each treatment period. RESULTS: Fifty-two patients were randomized and completed both treatment periods. The time in range for IDeg and CSII was 71.5% and 70.9%, respectively (P = .553). The time in level 1 hypoglycemia for the 24-hour period with IDeg and CSII was 2.19% and 1.75%, respectively (P = .065). The time in level 2 hypoglycemia for the 24-hour period with IDeg and CSII was 0.355% and 0.271%, respectively (P = .212), and the nocturnal period was 0.330% and 0.381%, respectively (P = .639). The mean standard deviation of blood glucose levels for the 24-hour period for IDeg and CSII was 52.4 mg/dL and 51.0 mg/dL, respectively (P = .294). The final hemoglobin A1C level for each treatment was 7.04% (53 mmol/mol) with IDeg, and 6.95% (52 mmol/mol) with CSII (P = .288). Adverse events were similar between treatments. CONCLUSION: We observed similar glycemic control between IDeg and insulin aspart via CSII for basal insulin coverage in patients with well-controlled type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Adulto , Glicemia , Automonitorização da Glicemia , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hemoglobinas Glicadas/análise , Controle Glicêmico , Humanos , Hipoglicemiantes , Insulina , Insulina Aspart , Insulina de Ação Prolongada
6.
Cult Health Sex ; 24(10): 1408-1422, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34365908

RESUMO

Menstruation research has largely focused on addressing menstrual management barriers facing cisgender women and girls in low and middle-income countries. Scant literature has assessed the menstrual management needs of trans and non-binary people assigned female at birth. To better understand these frequently invisibilised menstruation-related needs, we conducted a multi-method qualitative study in New York City which included: 17 in-depth interviews across trans and non-binary people (n = 10) and health care providers who serve them (n = 7); and seven anonymous post-interview participatory writing responses with trans and non-binary participants to further elucidate their lived experiences with menstrual management. Lack of health care provider transgender competency, public toilet design (i.e. gaps in cubicle doors and lack of in-cubicle menstrual product disposal bins), and the social dynamics of public toilets (i.e. work and school) were identified as significant barriers to managing menstruation safely and accessibly for trans and non-binary people. These findings have important implications for healthcare policy, public toilet legislation and advancing menstrual equity in the USA.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Menstruação , Feminino , Pessoal de Saúde , Humanos , Recém-Nascido , Produtos de Higiene Menstrual , Instituições Acadêmicas
7.
J Infect Dis ; 217(7): 1074-1077, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29300926

RESUMO

To determine rates of both symptomatic and asymptomatic infection among ambulatory adults, we collected nasopharyngeal swab specimens, demographic characteristics, and survey information from 1477 adult visitors to a New York City tourist attraction during April-July 2016. Multiplex polymerase chain reaction analysis was used to identify specimens positive for common respiratory viruses. A total of 7.2% of samples tested positive for respiratory viruses; among positive samples, 71.0% contained rhinovirus, and 21.5% contained coronavirus. Influenza virus, respiratory syncytial virus, and parainfluenza virus were also detected. Depending on symptomatologic definition, 57.7%-93.3% of positive samples were asymptomatic. These findings indicate that significant levels of asymptomatic respiratory viral shedding exist during summer among the ambulatory adult population.


Assuntos
Nasofaringe/virologia , Estações do Ano , Eliminação de Partículas Virais/fisiologia , Vírus/isolamento & purificação , Humanos , Reação em Cadeia da Polimerase Multiplex , Cidade de Nova Iorque , Vírus/classificação
8.
Gastroenterology ; 153(4): 1018-1025, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28711629

RESUMO

BACKGROUND AND AIMS: Duodenoscopes have been implicated in the transmission of multidrug-resistant organisms (MDRO). We compared the frequency of duodenoscope contamination with MDRO or any other bacteria after disinfection or sterilization by 3 different methods. METHODS: We performed a single-center prospective randomized study in which duodenoscopes were randomly reprocessed by standard high-level disinfection (sHLD), double high-level disinfection (dHLD), or standard high-level disinfection followed by ethylene oxide gas sterilization (HLD/ETO). Samples were collected from the elevator mechanism and working channel of each duodenoscope and cultured before use. The primary outcome was the proportion of duodenoscopes with an elevator mechanism or working channel culture showing 1 or more MDRO; secondary outcomes included the frequency of duodenoscope contamination with more than 0 and 10 or more colony-forming units (CFU) of aerobic bacterial growth on either sampling location. RESULTS: After 3 months of enrollment, the study was closed because of the futility; we did not observe sufficient events to evaluate the primary outcome. Among 541 duodenoscope culture events, 516 were included in the final analysis. No duodenoscope culture in any group was positive for MDRO. Bacterial growth of more than 0 CFU was noted in 16.1% duodenoscopes in the sHLD group, 16.0% in the dHLD group, and 22.5% in the HLD/ETO group (P = .21). Bacterial growth or 10 or more CFU was noted in 2.3% of duodenoscopes in the sHLD group, 4.1% in the dHLD group, and 4.2% in the HLD/ETO group (P = .36). MRDOs were cultured from 3.2% of pre-procedure rectal swabs and 2.5% of duodenal aspirates. CONCLUSIONS: In a comparison of duodenoscopes reprocessed by sHLD, dHLD, or HLD/ETO, we found no significant differences between groups for MDRO or bacteria contamination. Enhanced disinfection methods (dHLD or HLD/ETO) did not provide additional protection against contamination. However, insufficient events occurred to assess our primary study end-point. ClinicalTrials.gov no: NCT02611648.


Assuntos
Infecção Hospitalar/prevenção & controle , Desinfetantes , Desinfecção/métodos , Farmacorresistência Bacteriana Múltipla , Duodenoscópios/microbiologia , Duodenoscopia/instrumentação , Contaminação de Equipamentos/prevenção & controle , Reutilização de Equipamento , Óxido de Etileno , Esterilização/métodos , o-Ftalaldeído , Técnicas Bacteriológicas , Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , Duodenoscópios/efeitos adversos , Duodenoscopia/efeitos adversos , Gases , Humanos , Estudos Prospectivos , Fatores de Tempo
9.
Opt Lett ; 43(9): 2193-2196, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714787

RESUMO

We present the experimental observation of an optical spring without the use of an optical cavity. The optical spring is produced by interference at a beam splitter and, in principle, does not have the damping force associated with optical springs created in detuned cavities. The experiment consists of a Michelson-Sagnac interferometer (with no recycling cavities) with a partially reflective GaAs microresonator as the beam splitter that produces the optical spring. Our experimental measurements at input powers of up to 360 mW show the shift of the optical spring frequency as a function of power and are in excellent agreement with theoretical predictions. In addition, we show that the optical spring is able to keep the interferometer stable and locked without the use of external feedback.

10.
Structure ; 32(6): 739-750.e4, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38521071

RESUMO

Membrane forces shift the equilibria of mechanosensitive channels enabling them to convert mechanical cues into electrical signals. Molecular tools to stabilize and methods to capture their highly dynamic states are lacking. Cyclodextrins can mimic tension through the sequestering of lipids from membranes. Here we probe the conformational ensemble of MscS by EPR spectroscopy, the lipid environment with NMR, and function with electrophysiology under cyclodextrin-induced tension. We show the extent of MscS activation depends on the cyclodextrin-to-lipid ratio, and that lipids are depleted slower when MscS is present. This has implications in MscS' activation kinetics when distinct membrane scaffolds such as nanodiscs or liposomes are used. We find MscS transits from closed to sub-conducting state(s) before it desensitizes, due to the lack of lipid availability in its vicinity required for closure. Our approach allows for monitoring tension-sensitive states in membrane proteins and screening molecules capable of inducing molecular tension in bilayers.


Assuntos
Ciclodextrinas , Canais Iônicos , Bicamadas Lipídicas , Canais Iônicos/metabolismo , Canais Iônicos/química , Ciclodextrinas/química , Ciclodextrinas/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Bicamadas Lipídicas/metabolismo , Bicamadas Lipídicas/química , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Conformação Proteica , Escherichia coli/metabolismo , Escherichia coli/genética , Ativação do Canal Iônico , Mecanotransdução Celular , Lipossomos/metabolismo , Lipossomos/química , Modelos Moleculares
11.
J Int AIDS Soc ; 27 Suppl 1: e26282, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38965977

RESUMO

INTRODUCTION: Approval of the first long-acting injectable antiretroviral therapy (LAI ART) medication heralded a new era of HIV treatment. However, the years since approval have been marked by implementation challenges. The "Accelerating Implementation of Multilevel Strategies to Advance Long-Acting Injectable for Underserved Populations (ALAI UP Project)" aims to accelerate the systematic and equitable delivery of LAI ART. METHODS: We coded and analysed implementation barriers according to the Consolidated Framework for Implementation Research (CFIR) domains, desired resources and programme goals from questionnaire short-answer responses by clinics across the United States responding to ALAI UP's solicitation to participate in the project between November 2022 and January 2023. RESULTS: Thirty-eight clinics responded to ALAI UP's solicitation. The characteristics of LAI ART as an innovation (cost, complexity of procurement, dosing interval, limited eligibility) precipitated and interacted with barriers in other CFIR domains. Barriers included obtaining coverage for the cost of medication (27/38 clinics) (outer setting); need for new workflows and staffing (12/38) and/or systems to support injection scheduling/coordination (16/38), transportation and expanded clinic hours (13/38) (inner setting); and patient (10/38) and provider (7/38) education (individuals). To support implementation, applicants sought: technical assistance to develop protocols and workflows (18/38), specifically strategies to address payor challenges (8/38); additional staff for care coordination and benefits navigation (17/38); opportunities to share experiences with other implementing clinics (12/38); patient-facing materials to educate and increase demand (7/38); and support engaging communities (6/38). Clinics' LAI ART programme goals varied. Most prioritized delivering LAI ART to their most marginalized patients struggling to achieve viral suppression on oral therapy, despite awareness that current US Food and Drug Administration approval is only for virally suppressed patients. The goal for LAI ART reach after 1 year of implementation ranged from ≤10% of patients with HIV on LAI ART (17/38) to ≥50% of patients (2/38). CONCLUSIONS: Diverse clinic types are interested in offering LAI ART and most aspire to use LAI ART to support their most vulnerable patients sustain viral suppression. Dedicated resources centred on equity and relevant to context and population are needed to support implementation. Otherwise, the introduction of LAI ART risks exacerbating, not ameliorating, health disparities.


Assuntos
Infecções por HIV , Equidade em Saúde , Humanos , Infecções por HIV/tratamento farmacológico , Estados Unidos , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/administração & dosagem , Injeções , Inquéritos e Questionários , Antirretrovirais/uso terapêutico , Preparações de Ação Retardada , Acessibilidade aos Serviços de Saúde
12.
Biochemistry ; 52(51): 9275-85, 2013 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-24328089

RESUMO

The cis-syn thymine cyclobutane dimer is a DNA photoproduct implicated in skin cancer. We compared the stability of individual base pairs in thymine dimer-containing duplexes to undamaged parent 10-mer duplexes. UV melting thermodynamic measurements, CD spectroscopy, and 2D NOESY NMR spectroscopy confirm that the thymine dimer lesion is locally and moderately destabilizing within an overall B-form duplex conformation. We measured the rates of exchange of individual imino protons by NMR using magnetization transfer from water and determined the equilibrium constant for the opening of each base pair K(op). In the normal duplex K(op) decreases from the frayed ends of the duplex toward the center, such that the central TA pair is the most stable with a K(op) of 8 × 10⁻7. In contrast, base pair opening at the 5'T of the thymine dimer is facile. The 5'T of the dimer has the largest equilibrium constant (K(op) = 3 × 10⁻4) in its duplex, considerably larger than even the frayed penultimate base pairs. Notably, base pairing by the 3'T of the dimer is much more stable than by the 5'T, indicating that the predominant opening mechanism for the thymine dimer lesion is not likely to be flipping out into solution as a single unit. The dimer asymmetrically affects the stability of the duplex in its vicinity, destabilizing base pairing on its 5' side more than on the 3' side. The striking differences in base pair opening between parent and dimer duplexes occur independently of the duplex-single strand melting transitions.


Assuntos
Dano ao DNA , DNA de Forma B/química , Modelos Moleculares , Oligodesoxirribonucleotídeos/química , Dímeros de Pirimidina/química , Pareamento de Bases , Fenômenos Bioquímicos , Dicroísmo Circular , DNA de Forma B/metabolismo , Medição da Troca de Deutério , Cinética , Ressonância Magnética Nuclear Biomolecular , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Oligodesoxirribonucleotídeos/metabolismo , Prótons , Dímeros de Pirimidina/metabolismo , Estereoisomerismo
13.
Front Chem ; 11: 1162412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37021145

RESUMO

MscL was the first mechanosensitive ion channel identified in bacteria. The channel opens its large pore when the turgor pressure of the cytoplasm increases close to the lytic limit of the cellular membrane. Despite their ubiquity across organisms, their importance in biological processes, and the likelihood that they are one of the oldest mechanisms of sensory activation in cells, the exact molecular mechanism by which these channels sense changes in lateral tension is not fully understood. Modulation of the channel has been key to understanding important aspects of the structure and function of MscL, but a lack of molecular triggers of these channels hindered early developments in the field. Initial attempts to activate mechanosensitive channels and stabilize functionally relevant expanded or open states relied on mutations and associated post-translational modifications that were often cysteine reactive. These sulfhydryl reagents positioned at key residues have allowed the engineering of MscL channels for biotechnological purposes. Other studies have modulated MscL by altering membrane properties, such as lipid composition and physical properties. More recently, a variety of structurally distinct agonists have been shown bind to MscL directly, close to a transmembrane pocket that has been shown to have an important role in channel mechanical gating. These agonists have the potential to be developed further into antimicrobial therapies that target MscL, by considering the structural landscape and properties of these pockets.

14.
Appl Opt ; 51(29): 7069-79, 2012 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-23052087

RESUMO

We present flight results from the optical pointing control system onboard the Planetary Imaging Concept Testbed Using a Rocket Experiment (PICTURE) sounding rocket. PICTURE (NASA mission number: 36.225 UG) was launched on 8 October 2011, from White Sands Missile Range. It attempted to directly image the exozodiacal dust disk of ϵ Eridani (K2V, 3.22 pc) down to an inner radius of 1.5 AU using a visible nulling coronagraph. The rocket attitude control system (ACS) provided 627 milliarcsecond (mas) RMS body pointing (~2'' peak-to-valley). The PICTURE fine pointing system (FPS) successfully stabilized the telescope beam to 5.1 mas (0.02λ/D) RMS using an angle tracker camera and fast steering mirror. This level of pointing stability is comparable to that of the Hubble Space Telescope. We present the hardware design of the FPS, a description of the limiting noise sources and a power spectral density analysis of the FPS and rocket ACS in-flight performance.

15.
Appl Opt ; 51(15): 2877-87, 2012 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-22614589

RESUMO

Complementary metal-oxide semiconductor (CMOS)-hybrid arrays have become competitive optical detectors for use in ground- and space-based astronomy. Interpixel capacitance (IPC) is one source of error that appears in most CMOS arrays. In this paper, we use a single-pixel-reset method to model IPC. We combine this IPC model with a model for charge diffusion to estimate the total crosstalk on H4RG-10 arrays. Finally, we compare our model results to 55Fe data obtained using an astrometric camera built to test the H4RG-10 B0 generation detectors.

16.
STAR Protoc ; 3(3): 101562, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-35874470

RESUMO

Solvent accessibilities of and distances between protein residues measured by pulsed-EPR approaches provide high-resolution information on dynamic protein motions. We describe protocols for the purification and site-directed spin labeling of integral membrane proteins. In our protocol, peptide-level HDX-MS is used as a precursor to guide single-residue resolution ESEEM accessibility measurements and spin labeling strategies for EPR applications. Exploiting the pentameric MscL channel as a model, we discuss the use of cwEPR, DEER/PELDOR, and ESEEM spectroscopies to interrogate membrane protein dynamics. For complete details on the use and execution of this protocol, please refer to Wang et al. (2022).


Assuntos
Proteínas de Membrana , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Proteínas de Membrana/química , Marcadores de Spin
17.
Structure ; 30(4): 608-622.e5, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-34986323

RESUMO

The mechanosensitive ion channel of large conductance MscL gates in response to membrane tension changes. Lipid removal from transmembrane pockets leads to a concerted structural and functional MscL response, but it remains unknown whether there is a correlation between the tension-mediated state and the state derived by pocket delipidation in the absence of tension. Here, we combined pulsed electron paramagnetic resonance spectroscopy and hydrogen-deuterium exchange mass spectrometry, coupled with molecular dynamics simulations under membrane tension, to investigate the structural changes associated with the distinctively derived states. Whether it is tension- or modification-mediated pocket delipidation, we find that MscL samples a similar expanded subconducting state. This is the final step of the delipidation pathway, but only an intermediate stop on the tension-mediated path, with additional tension triggering further channel opening. Our findings hint at synergistic modes of regulation by lipid molecules in membrane tension-activated mechanosensitive channels.


Assuntos
Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Canais Iônicos/química , Bicamadas Lipídicas/metabolismo , Simulação de Dinâmica Molecular
18.
PLoS One ; 17(8): e0267766, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35939422

RESUMO

BACKGROUND: Widespread use of at-home rapid COVID-19 antigen tests has been proposed as an important public health intervention to interrupt chains of transmission. Antigen tests may be preferred over PCR because they provide on-demand results for relatively low cost and can identify people when they are most likely to be infectious, particularly when used daily. Yet the extent to which a frequent antigen testing intervention will result in a positive public health impact for COVID-19 will depend on high acceptability and high adherence to such regimens. METHODS: We conducted a mixed-methods study assessing acceptability of and adherence to a daily at-home mobile-app connected rapid antigen testing regimen among employees of a US-based media company. Acceptability was assessed across seven domains of the Theoretical Framework of Acceptability. RESULTS: Among 31 study participants, acceptability of the daily testing intervention was generally high, with participants reporting high perceived effectiveness, intervention coherence, and self-efficacy; positive affective attitude; acceptable degree of burden and opportunity cost; and assessing the intervention as ethical. 71% reported a preference to test daily using an at-home antigen test than weekly employment-based PCR. Mean adherence to the 21-day testing regimen was 88% with 43% of participants achieving 100% adherence, 48% testing at least every other day, and 10% testing less than every other day. CONCLUSIONS: Despite overall high acceptability and adherence, we identified three implementation challenges that must be addressed for frequent serial testing for COVID-19 to be implemented at scale and have a positive public health impact. First, users need guidance on how and when to adapt testing frequencies to different epidemiological conditions. Second, users and institutions need guidelines for how to safely store and share test results. Third, implementation of serial testing strategies must prioritize health equity and protect those most vulnerable to COVID-19.


Assuntos
COVID-19 , Aplicativos Móveis , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Atenção à Saúde , Humanos , Pandemias
19.
J Clin Virol Plus ; 2(3): 100080, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35528048

RESUMO

Background: SARS-CoV-2 antigen-based tests are well-calibrated to infectiousness and have a critical role to play in the COVID-19 public health response. We report the development and performance of a unique lateral flow immunoassay (LFA). Methods: Combinations of several monoclonal antibodies targeting multiple antigenic sites on the SARS-CoV-2 nucleocapsid protein (NP) were isolated, evaluated, and chosen for the development of a LFA termed CoV-SCAN (BioMedomics, Inc.). Clinical point-of-care studies in symptomatic and asymptomatic individuals were conducted to evaluate positive predictive agreement (PPA) and negative predictive agreement (NPA) with RT-PCR as comparator. Results: In laboratory testing, CoV-SCAN detected 14 recombinant N-proteins of SARS-CoV-2 variants with sensitivity in the range of 0.2-3.2 ng/mL, and 10 authentic SARS-CoV-2 variants with sensitivity in the range of 1.6-12.5 TCID50/swab. No cross reactivity was observed with other human coronaviruses or other respiratory pathogens. In clinical point-of-care testing on 148 individuals over age 2 with symptoms of ≤5 days, PPA was 87.2% (CI 95: 78.3-94.8%) and NPA was 100% (CI 95: 94.2-100%). In another 884 asymptomatic individuals, PPA was 85.7% (CI 95: 42.1-99.6%) and 99.7% (99.0-99.9%). Overall, CoV-SCAN detected over 97.2% of specimens with CT values <30 and 93.8% of nasal swab specimens with the Omicron variant, even within the first 2 days after symptom onset. Conclusions: The unique construction of CoV-SCAN using two pairs of monoclonal antibodies has resulted in a test with high performance that remains durable across multiple variants in both laboratory and clinical evaluations. CoV-SCAN should identify almost all individuals harboring infectious SARS-CoV-2. Summary: Unique construction of a point-of-care rapid antigen test using two pairs of monoclonal antibodies has led to good performance that remained durable across multiple variants in laboratory and clinical evaluations. Test should identify almost all individuals harboring infectious SARS-CoV-2.

20.
Biochemistry ; 50(39): 8463-77, 2011 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-21902242

RESUMO

The base lesion 8-oxoguanine is formed readily by oxidation of DNA, potentially leading to G → T transversion mutations. Despite the apparent similarity of 8-oxoguanine-cytosine base pairs to normal guanine-cytosine base pairs, cellular base excision repair systems effectively recognize the lesion base. Here we apply several techniques to examine a single 8-oxoguanine lesion at the center of a nonpalindromic 15-mer duplex oligonucleotide in an effort to determine what, if anything, distinguishes an 8-oxoguanine-cytosine (8oxoG-C) base pair from a normal base pair. The lesion duplex is globally almost indistinguishable from the unmodified parent duplex using circular dichroism spectroscopy and ultraviolet melting thermodynamics. The DNA mismatch-detecting photocleavage agent Rh(bpy)(2)chrysi(3+) cleaves only weakly and nonspecifically, revealing that the 8oxoG-C pair is locally stable at the level of the individual base pairs. Nuclear magnetic resonance spectra are also consistent with a well-conserved B-form duplex structure. In the two-dimensional nuclear Overhauser effect spectra, base-sugar and imino-imino cross-peaks are strikingly similar between parent and lesion duplexes. Changes in chemical shift due to the 8oxoG lesion are localized to its complementary cytosine and to the 2-3 bp immediately flanking the lesion on the lesion strand. Residues further removed from the lesion are shown to be unperturbed by its presence. Notably, imino exchange experiments indicate that the 8-oxoguanine-cytosine pair is strong and stable, with an apparent equilibrium constant for opening equal to that of other internal guanine-cytosine base pairs, on the order of 10(-6). This collection of experiments shows that the 8-oxoguanine-cytosine base pair is incredibly stable and similar to the native pair.


Assuntos
Pareamento de Bases , Dano ao DNA , Guanina/análogos & derivados , Oligodesoxirribonucleotídeos/química , Sequência de Bases , Dano ao DNA/efeitos dos fármacos , Reparo do DNA , Guanina/síntese química , Guanina/química , Espectroscopia de Ressonância Magnética , Termodinâmica
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