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1.
Lancet Microbe ; 5(5): e468-e477, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38621394

RESUMO

BACKGROUND: Sequencing of SARS-CoV-2 from rapid diagnostic tests (RDTs) can bolster viral genomic surveillance efforts; however, approaches to maximise and standardise pathogen genome recovery from RDTs remain underdeveloped. We aimed to systematically optimise the elution of genetic material from RDT components and to evaluate the efficacy of RDT sequencing for outbreak investigation. METHODS: In this laboratory and cohort-based study we seeded RDTs with inactivated SARS-CoV-2 to optimise the elution of genomic material from RDT lateral flow strips. We measured the effect of changes in buffer type, time in buffer, and rotation on PCR cycle threshold (Ct) value. We recruited individuals older than 18 years residing in the greater Boston area, MA, USA, from July 18 to Nov 5, 2022, via email advertising to students and staff at Harvard University, MA, USA, and via broad social media advertising. All individuals recruited were within 5 days of a positive diagnostic test for SARS-CoV-2; no other relevant exclusion criteria were applied. Each individual completed two RDTs and one PCR swab. On Dec 29, 2022, we also collected RDTs from a convenience sample of individuals who were positive for SARS-CoV-2 and associated with an outbreak at a senior housing facility in MA, USA. We extracted all returned PCR swabs and RDT components (ie, swab, strip, or buffer); samples with a Ct of less than 40 were subject to amplicon sequencing. We compared the efficacy of elution and sequencing across RDT brands and components and used RDT-derived sequences to infer transmission links within the outbreak at the senior housing facility. We conducted metagenomic sequencing of negative RDTs from symptomatic individuals living in the senior housing facility. FINDINGS: Neither elution duration of greater than 10 min nor rotation during elution impacted viral titres. Elution in Buffer AVL (Ct=31·4) and Tris-EDTA Buffer (Ct=30·8) were equivalent (p=0·34); AVL outperformed elution in lysis buffer and 50% lysis buffer (Ct=40·0, p=0·0029 for both) as well as Universal Viral Transport Medium (Ct=36·7, p=0·079). Performance of RDT strips was poorer than that of matched PCR swabs (mean Ct difference 10·2 [SD 4·3], p<0·0001); however, RDT swabs performed similarly to PCR swabs (mean Ct difference 4·1 [5·2], p=0·055). No RDT brand significantly outperformed another. Across sample types, viral load predicted the viral genome assembly length. We assembled greater than 80% complete genomes from 12 of 17 RDT-derived swabs, three of 18 strips, and four of 11 residual buffers. We generated outbreak-associated SARS-CoV-2 genomes using both amplicon and metagenomic sequencing and identified multiple introductions of the virus that resulted in downstream transmission. INTERPRETATION: RDT-derived swabs are a reasonable alternative to PCR swabs for viral genomic surveillance and outbreak investigation. RDT-derived lateral flow strips yield accurate, but significantly fewer, viral reads than matched PCR swabs. Metagenomic sequencing of negative RDTs can identify viruses that might underlie patient symptoms. FUNDING: The National Science Foundation, the Hertz Foundation, the National Institute of General Medical Sciences, Harvard Medical School, the Howard Hughes Medical Institute, the US Centers for Disease Control and Prevention, the Broad Institute and the National Institute of Allergy and Infectious Diseases.


Assuntos
COVID-19 , Genoma Viral , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/virologia , COVID-19/epidemiologia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Estudos de Coortes , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Genoma Viral/genética , Idoso , Teste para COVID-19/métodos , Testes Diagnósticos de Rotina/métodos , Teste de Ácido Nucleico para COVID-19/métodos , Adulto Jovem , Testes de Diagnóstico Rápido
2.
medRxiv ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38370621

RESUMO

Background: Households are a major setting for SARS-CoV-2 infections, but there remains a lack of knowledge regarding the dynamics of viral transmission, particularly in the setting of widespread pre-existing SARS-CoV-2 immunity and evolving variants. Methods: We conducted a prospective, case-ascertained household transmission study in the greater Boston area in March-July 2022. Anterior nasal swabs, along with clinical and demographic data, were collected for 14 days. Nasal swabs were tested for SARS-CoV-2 by PCR. Whole genome sequencing was performed on high-titer samples. Results: We enrolled 33 households in a primary analysis set, with a median age of participants of 25 years old (range 2-66); 98% of whom had received at least 2 doses of a COVID-19 vaccine. 58% of households had a secondary case during follow up and the secondary attack rate (SAR) for contacts infected was 39%. We further examined a strict analysis set of 21 households that had only 1 PCR+ case at baseline, finding an SAR of 22.5%. Genomic epidemiology further determined that there were multiple sources of infection for household contacts, including the index case and outside introductions. When limiting estimates to only highly probable transmissions given epidemiologic and genomic data, the SAR was 18.4%. Conclusions: Household contacts of a person newly diagnosed with COVID-19 are at high risk for SARS-CoV-2 infection in the following 2 weeks. This is, however, not only due to infection from the household index case, but also because the presence of an infected household member implies increased SARS-CoV-2 community transmission. Further studies to understand and mitigate household transmission are needed.

3.
ACS Biomater Sci Eng ; 10(4): 2351-2366, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38323834

RESUMO

Electrically conductive biomaterials and nanomaterials have demonstrated great potential in the development of functional and mature cardiac tissues. In particular, gold nanomaterials have emerged as promising candidates due to their biocompatibility and ease of fabrication for cardiac tissue engineering utilizing rat- or stem cell-derived cardiomyocytes (CMs). However, despite significant advancements, it is still not clear whether the enhancement in cardiac tissue function is primarily due to the electroconductivity features of gold nanoparticles or the structural changes of the scaffold resulting from the addition of these nanoparticles. To address this question, we developed nanoengineered hydrogel scaffolds comprising gelatin methacrylate (GelMA) embedded with either electrically conductive gold nanorods (GNRs) or nonconductive silica nanoparticles (SNPs). This enabled us to simultaneously assess the roles of electrically conductive and nonconductive nanomaterials in the functionality and fate of human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Our studies revealed that both GNR- and SNP-incorporated hydrogel scaffolds exhibited excellent biocompatibility and similar cardiac cell attachment. Although the expression of sarcomere alpha-actinin did not significantly differ among the conditions, a more organized sarcomere structure was observed within the GNR-embedded hydrogels compared to the nonconductive nanoengineered scaffolds. Furthermore, electrical coupling was notably improved in GNR-embedded scaffolds, as evidenced by the synchronous calcium flux and enhanced calcium transient intensity. While we did not observe a significant difference in the gene expression profile of human cardiac tissues formed on the conductive GNR- and nonconductive SNP-incorporated hydrogels, we noticed marginal improvements in the expression of some calcium and structural genes in the nanomaterial-embedded hydrogel groups as compared to the control condition. Given that the cardiac tissues formed atop the nonconductive SNP-based scaffolds (used as the control for conductivity) also displayed similar levels of gene expression as compared to the conductive hydrogels, it suggests that the electrical conductivity of nanomaterials (i.e., GNRs) may not be the sole factor influencing the function and fate of hiPSC-derived cardiac tissues when cells are cultured atop the scaffolds. Overall, our findings provide additional insights into the role of electrically conductive gold nanoparticles in regulating the functionalities of hiPSC-CMs.


Assuntos
Nanopartículas Metálicas , Engenharia Tecidual , Humanos , Ratos , Animais , Engenharia Tecidual/métodos , Ouro , Dióxido de Silício , Hidrogéis/química , Cálcio/metabolismo , Células-Tronco
4.
medRxiv ; 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37873325

RESUMO

Genome sequencing can offer critical insight into pathogen spread in viral outbreaks, but existing transmission inference methods use simplistic evolutionary models and only incorporate a portion of available genetic data. Here, we develop a robust evolutionary model for transmission reconstruction that tracks the genetic composition of within-host viral populations over time and the lineages transmitted between hosts. We confirm that our model reliably describes within-host variant frequencies in a dataset of 134,682 SARS-CoV-2 deep-sequenced genomes from Massachusetts, USA. We then demonstrate that our reconstruction approach infers transmissions more accurately than two leading methods on synthetic data, as well as in a controlled outbreak of bovine respiratory syncytial virus and an epidemiologically-investigated SARS-CoV-2 outbreak in South Africa. Finally, we apply our transmission reconstruction tool to 5,692 outbreaks among the 134,682 Massachusetts genomes. Our methods and results demonstrate the utility of within-host variation for transmission inference of SARS-CoV-2 and other pathogens, and provide an adaptable mathematical framework for tracking within-host evolution.

5.
Health Aff (Millwood) ; 42(3): 349-356, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36877907

RESUMO

Throughout the COVID-19 pandemic, the US has struggled with many aspects of the public health response, from determining where transmission is occurring to building trust with communities and implementing interventions. Three factors have contributed to these challenges: insufficient local public health capacity, siloed interventions, and underuse of a cluster-based approach to outbreak response. In this article we introduce Community-based Outbreak Investigation and Response (COIR), a local public health strategy developed during the COVID-19 pandemic that addresses these shortcomings. COIR can help local public health entities conduct disease surveillance more effectively, take a more proactive and efficient approach to mitigating transmission, coordinate response efforts, build community trust, and advance equity. We offer a practitioner's lens, informed through on-the-ground experience and engagement with policy makers, to highlight the financing, workforce, data system, and information-sharing policy changes needed to scale up COIR throughout the country. COIR can enable the US public health system to develop effective solutions to many of today's public health challenges and improve the nation's preparedness for public health crises in the years to come.


Assuntos
COVID-19 , Saúde Pública , Humanos , Pandemias/prevenção & controle , COVID-19/epidemiologia , Surtos de Doenças/prevenção & controle , Pessoal Administrativo
7.
medRxiv ; 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36656774

RESUMO

The US experienced an early and severe respiratory syncytial virus (RSV) surge in autumn 2022. Despite the pressure this has put on hospitals and care centers, the factors promoting the surge in cases are unknown. To investigate whether viral characteristics contributed to the extent or severity of the surge, we sequenced 105 RSV-positive specimens from symptomatic patients diagnosed with RSV who presented to the Massachusetts General Hospital (MGH) and its outpatient practices in the Greater Boston Area. Genomic analysis of the resulting 77 genomes (54 with >80% coverage, and 23 with >5% coverage) demonstrated that the surge was driven by multiple lineages of RSV-A (91%; 70/77) and RSV-B (9%; 7/77). Phylogenetic analysis of all US RSV-A revealed 12 clades, 4 of which contained Massachusetts and Washington genomes. These clades individually had times to most recent common ancestor (tMRCA) between 2014 and 2017, and together had a tMRCA of 2009, suggesting that they emerged well before the COVID-19 pandemic. Similarly, the RSV-B genomes had a tMRCA between 2016 and 2019. We found that the RSV-A and RSV-B genomes in our sample did not differ statistically from the estimated clock rate of the larger phylogenetic tree (10.6 and 12.4 substitutions per year, respectively). In summary, the polyphyletic nature of viral genomes sequenced in the US during the autumn 2022 surge is inconsistent with the emergence of a single, highly transmissible causal RSV lineage.

8.
Med ; 3(12): 883-900.e13, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36198312

RESUMO

BACKGROUND: Universities are vulnerable to infectious disease outbreaks, making them ideal environments to study transmission dynamics and evaluate mitigation and surveillance measures. Here, we analyze multimodal COVID-19-associated data collected during the 2020-2021 academic year at Colorado Mesa University and introduce a SARS-CoV-2 surveillance and response framework. METHODS: We analyzed epidemiological and sociobehavioral data (demographics, contact tracing, and WiFi-based co-location data) alongside pathogen surveillance data (wastewater and diagnostic testing, and viral genomic sequencing of wastewater and clinical specimens) to characterize outbreak dynamics and inform policy. We applied relative risk, multiple linear regression, and social network assortativity to identify attributes or behaviors associated with contracting SARS-CoV-2. To characterize SARS-CoV-2 transmission, we used viral sequencing, phylogenomic tools, and functional assays. FINDINGS: Athletes, particularly those on high-contact teams, had the highest risk of testing positive. On average, individuals who tested positive had more contacts and longer interaction durations than individuals who never tested positive. The distribution of contacts per individual was overdispersed, although not as overdispersed as the distribution of phylogenomic descendants. Corroboration via technical replicates was essential for identification of wastewater mutations. CONCLUSIONS: Based on our findings, we formulate a framework that combines tools into an integrated disease surveillance program that can be implemented in other congregate settings with limited resources. FUNDING: This work was supported by the National Science Foundation, the Hertz Foundation, the National Institutes of Health, the Centers for Disease Control and Prevention, the Massachusetts Consortium on Pathogen Readiness, the Howard Hughes Medical Institute, the Flu Lab, and the Audacious Project.


Assuntos
COVID-19 , SARS-CoV-2 , Estados Unidos , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Surtos de Doenças , Universidades , Busca de Comunicante
9.
medRxiv ; 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35982651

RESUMO

We measured viral kinetics of SARS-CoV-2 Omicron infection in 36 mRNA-vaccinated individuals, 11 of whom were treated with nirmatrelvir-ritonavir (NMV-r). We found that NMV-r was associated with greater incidence of viral rebound compared to no treatment. For those that did not rebound, NMV-r significantly reduced time to PCR conversion.

10.
MMWR Morb Mortal Wkly Rep ; 70(31): 1059-1062, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34351882

RESUMO

During July 2021, 469 cases of COVID-19 associated with multiple summer events and large public gatherings in a town in Barnstable County, Massachusetts, were identified among Massachusetts residents; vaccination coverage among eligible Massachusetts residents was 69%. Approximately three quarters (346; 74%) of cases occurred in fully vaccinated persons (those who had completed a 2-dose course of mRNA vaccine [Pfizer-BioNTech or Moderna] or had received a single dose of Janssen [Johnson & Johnson] vaccine ≥14 days before exposure). Genomic sequencing of specimens from 133 patients identified the B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, in 119 (89%) and the Delta AY.3 sublineage in one (1%). Overall, 274 (79%) vaccinated patients with breakthrough infection were symptomatic. Among five COVID-19 patients who were hospitalized, four were fully vaccinated; no deaths were reported. Real-time reverse transcription-polymerase chain reaction (RT-PCR) cycle threshold (Ct) values in specimens from 127 vaccinated persons with breakthrough cases were similar to those from 84 persons who were unvaccinated, not fully vaccinated, or whose vaccination status was unknown (median = 22.77 and 21.54, respectively). The Delta variant of SARS-CoV-2 is highly transmissible (1); vaccination is the most important strategy to prevent severe illness and death. On July 27, CDC recommended that all persons, including those who are fully vaccinated, should wear masks in indoor public settings in areas where COVID-19 transmission is high or substantial.* Findings from this investigation suggest that even jurisdictions without substantial or high COVID-19 transmission might consider expanding prevention strategies, including masking in indoor public settings regardless of vaccination status, given the potential risk of infection during attendance at large public gatherings that include travelers from many areas with differing levels of transmission.


Assuntos
COVID-19/epidemiologia , COVID-19/transmissão , Aglomeração , Surtos de Doenças , Adolescente , Adulto , Idoso , Vacinas contra COVID-19/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Adulto Jovem
11.
Clin J Oncol Nurs ; 24(1): 65-74, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31961839

RESUMO

BACKGROUND: The lack of coordination of care for complex patients in the hematology setting has prompted nurse case managers (NCMs) to coordinate that care. OBJECTIVES: This article aimed to identify the frequency of NCM care coordination activities and quality and resource use outcomes in the complex care of patients in the hematology setting. METHODS: NCM aggregate data from complex outpatients with hematologic cancer were retrieved from electronic health records at a comprehensive cancer center in the midwestern United States. Total volume of activities and outcomes were calculated as frequency and percentage. FINDINGS: Care coordination activities included communicating; monitoring, following up, and responding to change; and creating a proactive plan of care. Quality outcomes included improving continuity of care and change in health behavior, and resource use outcomes most documented were patient healthcare cost savings.


Assuntos
Administração de Caso/organização & administração , Neoplasias Hematológicas/enfermagem , Cuidados de Enfermagem/organização & administração , Avaliação de Resultados em Cuidados de Saúde/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Gerentes de Casos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos , Organização e Administração , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos
12.
Mol Metab ; 11: 160-177, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29525407

RESUMO

OBJECTIVE: Given that cellular O-GlcNAcylation levels are thought to be real-time measures of cellular nutrient status and dysregulated O-GlcNAc signaling is associated with insulin resistance, we evaluated the role of O-GlcNAc transferase (OGT), the enzyme that mediates O-GlcNAcylation, in skeletal muscle. METHODS: We assessed O-GlcNAcylation levels in skeletal muscle from obese, type 2 diabetic people, and we characterized muscle-specific OGT knockout (mKO) mice in metabolic cages and measured energy expenditure and substrate utilization pattern using indirect calorimetry. Whole body insulin sensitivity was assessed using the hyperinsulinemic euglycemic clamp technique and tissue-specific glucose uptake was subsequently evaluated. Tissues were used for histology, qPCR, Western blot, co-immunoprecipitation, and chromatin immunoprecipitation analyses. RESULTS: We found elevated levels of O-GlcNAc-modified proteins in obese, type 2 diabetic people compared with well-matched obese and lean controls. Muscle-specific OGT knockout mice were lean, and whole body energy expenditure and insulin sensitivity were increased in these mice, consistent with enhanced glucose uptake and elevated glycolytic enzyme activities in skeletal muscle. Moreover, enhanced glucose uptake was also observed in white adipose tissue that was browner than that of WT mice. Interestingly, mKO mice had elevated mRNA levels of Il15 in skeletal muscle and increased circulating IL-15 levels. We found that OGT in muscle mediates transcriptional repression of Il15 by O-GlcNAcylating Enhancer of Zeste Homolog 2 (EZH2). CONCLUSIONS: Elevated muscle O-GlcNAc levels paralleled insulin resistance and type 2 diabetes in humans. Moreover, OGT-mediated signaling is necessary for proper skeletal muscle metabolism and whole-body energy homeostasis, and our data highlight O-GlcNAcylation as a potential target for ameliorating metabolic disorders.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina , Músculo Esquelético/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Tecido Adiposo/metabolismo , Animais , Diabetes Mellitus Tipo 2/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Homeostase , Humanos , Interleucina-15/sangue , Interleucina-15/genética , Interleucina-15/metabolismo , Camundongos , N-Acetilglucosaminiltransferases/genética
13.
Clin Vaccine Immunol ; 21(10): 1463-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25143338

RESUMO

An enzyme-linked immunosorbent assay (ELISA) was developed to detect bovine antibodies to Histophilus somni exopolysaccharide (EPS), which is created during biofilm formation. When an index value of 0.268 was used, the sensitivity of the assay for infected calves was 90.5% at 3 weeks postinfection, but the number of positive animals increased by week 4. The specificity of the assay for healthy calves was 92.5%. The EPS ELISA may aid in identifying calves with H. somni diseases.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/imunologia , Infecções por Pasteurellaceae/veterinária , Pasteurellaceae/imunologia , Polissacarídeos Bacterianos/imunologia , Medicina Veterinária/métodos , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/métodos , Infecções por Pasteurellaceae/diagnóstico , Infecções por Pasteurellaceae/imunologia , Sensibilidade e Especificidade , Testes Sorológicos/métodos
14.
Proc Inst Mech Eng H ; 228(3): 303-18, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24534419

RESUMO

Magnetic resonance imaging presents high-resolution preoperative scans of target tissue and allows for the availability of intraoperative real-time images without the exposure of patients to ionizing radiation. This has motivated scientists and engineers to integrate medical robotics with the magnetic resonance imaging modality to allow robot-assisted, image-guided diagnosis and therapy. This article provides a review of the state-of-the-art medical robotic systems available for use in conjunction with intraoperative magnetic resonance imaging. The robot functionalities and mechanical designs for a wide range of magnetic resonance imaging interventions are presented, including their magnetic resonance imaging compatibility, actuation, kinematics and the mechanical and electrical designs of the robots. Classification and comparative study of various intraoperative magnetic resonance image guided robotic systems are provided. The robotic systems reviewed are summarized in a table in detail. Current technologies for magnetic resonance imaging-conditional robotics are reviewed and their potential future directions are sketched.


Assuntos
Diagnóstico por Computador/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Robótica/instrumentação , Cirurgia Assistida por Computador/instrumentação , Humanos
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