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1.
J Family Med Prim Care ; 12(11): 2797-2804, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38186770

RESUMO

Introduction: Earlier, patients with advanced ovarian cancer were treated with a combination of cytoreductive surgery and platinum-based chemotherapy, which had significant outcomes in the past until an increase in relapse and resistance to treatment, which led to the use or development of bevacizumab (a vascular endothelial growth factor inhibitor) in the treatment of primary or relapsed ovarian cancer. Method and Methodology: This study includes five-phase three randomized controlled clinical trials designed to study the impact of bevacizumab in combination with platinum-based chemotherapy compared with platinum-based chemotherapy alone. Results: This study demonstrated significant improvement in the progression-free span but no improvement in overall survival in the treatment group when compared with the control group. Also, adverse effects reported with combination therapy were tolerable and easily manageable by decreasing the infusion rate or by decreasing the frequency of infusion.

2.
Clin Infect Dis ; 75(1): e105-e113, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35213690

RESUMO

BACKGROUND: Estimating the cumulative incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for setting public health policies. We leveraged deidentified Massachusetts newborn screening specimens as an accessible, retrospective source of maternal antibodies for estimating statewide seroprevalence in a nontest-seeking population. METHODS: We analyzed 72 117 newborn specimens collected from November 2019 through December 2020, representing 337 towns and cities across Massachusetts. Seroprevalence was estimated for the Massachusetts population after correcting for imperfect test specificity and nonrepresentative sampling using Bayesian multilevel regression and poststratification. RESULTS: Statewide seroprevalence was estimated to be 0.03% (90% credible interval [CI], 0.00-0.11) in November 2019 and rose to 1.47% (90% CI: 1.00-2.13) by May 2020, following sustained SARS-CoV-2 transmission in the spring. Seroprevalence plateaued from May onward, reaching 2.15% (90% CI: 1.56-2.98) in December 2020. Seroprevalence varied substantially by community and was particularly associated with community percent non-Hispanic Black (ß = .024; 90% CI: 0.004-0.044); i.e., a 10% increase in community percent non-Hispanic Black was associated with 27% higher odds of seropositivity. Seroprevalence estimates had good concordance with reported case counts and wastewater surveillance for most of 2020, prior to the resurgence of transmission in winter. CONCLUSIONS: Cumulative incidence of SARS-CoV-2 protective antibody in Massachusetts was low as of December 2020, indicating that a substantial fraction of the population was still susceptible. Maternal seroprevalence data from newborn screening can inform longitudinal trends and identify cities and towns at highest risk, particularly in settings where widespread diagnostic testing is unavailable.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Teorema de Bayes , COVID-19/diagnóstico , COVID-19/epidemiologia , Humanos , Recém-Nascido , Triagem Neonatal , Estudos Retrospectivos , Estudos Soroepidemiológicos , Águas Residuárias , Vigilância Epidemiológica Baseada em Águas Residuárias
3.
PLoS Biol ; 20(2): e3001531, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35143473

RESUMO

Identifying the potential for SARS-CoV-2 reinfection is crucial for understanding possible long-term epidemic dynamics. We analysed longitudinal PCR and serological testing data from a prospective cohort of 4,411 United States employees in 4 states between April 2020 and February 2021. We conducted a multivariable logistic regression investigating the association between baseline serological status and subsequent PCR test result in order to calculate an odds ratio for reinfection. We estimated an odds ratio for reinfection ranging from 0.14 (95% CI: 0.019 to 0.63) to 0.28 (95% CI: 0.05 to 1.1), implying that the presence of SARS-CoV-2 antibodies at baseline is associated with around 72% to 86% reduced odds of a subsequent PCR positive test based on our point estimates. This suggests that primary infection with SARS-CoV-2 provides protection against reinfection in the majority of individuals, at least over a 6-month time period. We also highlight 2 major sources of bias and uncertainty to be considered when estimating the relative risk of reinfection, confounders and the choice of baseline time point, and show how to account for both in reinfection analysis.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/imunologia , Reinfecção/imunologia , Adolescente , Adulto , Idoso , COVID-19/epidemiologia , COVID-19/prevenção & controle , Teste de Ácido Nucleico para COVID-19 , Teste Sorológico para COVID-19 , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Prospectivos , Reinfecção/prevenção & controle , SARS-CoV-2/imunologia , Estudos Soroepidemiológicos , Fatores de Tempo , Estados Unidos/epidemiologia , Local de Trabalho/estatística & dados numéricos , Adulto Jovem
4.
mBio ; 13(1): e0214121, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35073738

RESUMO

As public health guidelines throughout the world have relaxed in response to vaccination campaigns against SARS-CoV-2, it is likely that SARS-CoV-2 will remain endemic, fueled by the rise of more infectious SARS-CoV-2 variants. Moreover, in the setting of waning natural and vaccine immunity, reinfections have emerged across the globe, even among previously infected and vaccinated individuals. As such, the ability to detect reexposure to and reinfection by SARS-CoV-2 is a key component for global protection against this virus and, more importantly, against the potential emergence of vaccine escape mutations. Accordingly, there is a strong and continued need for the development and deployment of simple methods to detect emerging hot spots of reinfection to inform targeted pandemic response and containment, including targeted and specific deployment of vaccine booster campaigns. In this study, we identify simple, rapid immune biomarkers of reinfection in rhesus macaques, including IgG3 antibody levels against nucleocapsid and FcγR2A receptor binding activity of anti-RBD antibodies, that are recapitulated in human reinfection cases. As such, this cross-species analysis underscores the potential utility of simple antibody titers and function as price-effective and scalable markers of reinfection to provide increased resolution and resilience against new outbreaks. IMPORTANCE As public health and social distancing guidelines loosen in the setting of waning global natural and vaccine immunity, a deeper understanding of the immunological response to reexposure and reinfection to this highly contagious pathogen is necessary to maintain public health. Viral sequencing analysis provides a robust but unrealistic means to monitor reinfection globally. The identification of scalable pathogen-specific biomarkers of reexposure and reinfection, however, could significantly accelerate our capacity to monitor the spread of the virus through naive and experienced hosts, providing key insights into mechanisms of disease attenuation. Using a nonhuman primate model of controlled SARS-CoV-2 reexposure, we deeply probed the humoral immune response following rechallenge with various doses of viral inocula. We identified virus-specific humoral biomarkers of reinfection, with significant increases in antibody titer and function upon rechallenge across a range of humoral features, including IgG1 to the receptor binding domain of the spike protein of SARS-CoV-2 (RBD), IgG3 to the nucleocapsid protein (N), and FcγR2A receptor binding to anti-RBD antibodies. These features not only differentiated primary infection from reexposure and reinfection in monkeys but also were recapitulated in a sequencing-confirmed reinfection patient and in a cohort of putatively reinfected humans that evolved a PCR-positive test in spite of preexisting seropositivity. As such, this cross-species analysis using a controlled primate model and human cohorts reveals increases in antibody titers as promising cross-validated serological markers of reinfection and reexposure.


Assuntos
COVID-19 , Reinfecção , Animais , Humanos , Macaca mulatta , SARS-CoV-2 , Imunoglobulina G , Anticorpos Antivirais , Anticorpos Neutralizantes
5.
Viruses ; 13(11)2021 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-34835041

RESUMO

Obesity is a key correlate of severe SARS-CoV-2 outcomes while the role of obesity on risk of SARS-CoV-2 infection, symptom phenotype, and immune response remain poorly defined. We examined data from a prospective SARS-CoV-2 cohort study to address these questions. Serostatus, body mass index, demographics, comorbidities, and prior COVID-19 compatible symptoms were assessed at baseline and serostatus and symptoms monthly thereafter. SARS-CoV-2 immunoassays included an IgG ELISA targeting the spike RBD, multiarray Luminex targeting 20 viral antigens, pseudovirus neutralization, and T cell ELISPOT assays. Our results from a large prospective SARS-CoV-2 cohort study indicate symptom phenotype is strongly influenced by obesity among younger but not older age groups; we did not identify evidence to suggest obese individuals are at higher risk of SARS-CoV-2 infection; and remarkably homogenous immune activity across BMI categories suggests immune protection across these groups may be similar.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/complicações , COVID-19/imunologia , Obesidade/complicações , Obesidade/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adolescente , Adulto , Fatores Etários , Índice de Massa Corporal , COVID-19/epidemiologia , COVID-19/fisiopatologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , SARS-CoV-2/imunologia , Adulto Jovem
6.
Nat Commun ; 12(1): 1018, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589636

RESUMO

Antibodies serve as biomarkers of infection, but if sustained can confer long-term immunity. Yet, for most clinically approved vaccines, binding antibody titers only serve as a surrogate of protection. Instead, the ability of vaccine induced antibodies to neutralize or mediate Fc-effector functions is mechanistically linked to protection. While evidence has begun to point to persisting antibody responses among SARS-CoV-2 infected individuals, cases of re-infection have begun to emerge, calling the protective nature of humoral immunity against this highly infectious pathogen into question. Using a community-based surveillance study, we aimed to define the relationship between titers and functional antibody activity to SARS-CoV-2 over time. Here we report significant heterogeneity, but limited decay, across antibody titers amongst 120 identified seroconverters, most of whom had asymptomatic infection. Notably, neutralization, Fc-function, and SARS-CoV-2 specific T cell responses were only observed in subjects that elicited RBD-specific antibody titers above a threshold. The findings point to a switch-like relationship between observed antibody titer and function, where a distinct threshold of activity-defined by the level of antibodies-is required to elicit vigorous humoral and cellular response. This response activity level may be essential for durable protection, potentially explaining why re-infections occur with SARS-CoV-2 and other common coronaviruses.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , COVID-19/sangue , Feminino , Humanos , Imunidade Humoral/imunologia , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinas Virais/imunologia , Adulto Jovem
7.
medRxiv ; 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33200139

RESUMO

Obesity is a key correlate of severe SARS-CoV-2 outcomes while the role of obesity on risk of SARS-CoV-2 infection, symptom phenotype, and immune response are poorly defined. We examined data from a prospective SARS-CoV-2 cohort study to address these questions. Serostatus, body mass index, demographics, comorbidities, and prior COVID-19 compatible symptoms were assessed at baseline and serostatus and symptoms monthly thereafter. SARS-CoV-2 immunoassays included an IgG ELISA targeting the spike RBD, multiarray Luminex targeting 20 viral antigens, pseudovirus neutralization, and T cell ELISPOT assays. Our results from a large prospective SARS-CoV-2 cohort study indicate symptom phenotype is strongly influenced by obesity among younger but not older age groups; we did not identify evidence to suggest obese individuals are at higher risk of SARS-CoV-2 infection; and, remarkably homogenous immune activity across BMI categories suggests natural- and vaccine-induced protection may be similar across these groups.

8.
Nat Commun ; 11(1): 5921, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219225

RESUMO

The COVID-19 pandemic has highlighted that new diagnostic technologies are essential for controlling disease transmission. Here, we develop SHINE (Streamlined Highlighting of Infections to Navigate Epidemics), a sensitive and specific diagnostic tool that can detect SARS-CoV-2 RNA from unextracted samples. We identify the optimal conditions to allow RPA-based amplification and Cas13-based detection to occur in a single step, simplifying assay preparation and reducing run-time. We improve HUDSON to rapidly inactivate viruses in nasopharyngeal swabs and saliva in 10 min. SHINE's results can be visualized with an in-tube fluorescent readout - reducing contamination risk as amplification reaction tubes remain sealed - and interpreted by a companion smartphone application. We validate SHINE on 50 nasopharyngeal patient samples, demonstrating 90% sensitivity and 100% specificity compared to RT-qPCR with a sample-to-answer time of 50 min. SHINE has the potential to be used outside of hospitals and clinical laboratories, greatly enhancing diagnostic capabilities.


Assuntos
Betacoronavirus/isolamento & purificação , Proteínas Associadas a CRISPR/metabolismo , Técnicas de Diagnóstico Molecular/métodos , Bioensaio , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Fluorescência , Humanos , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , SARS-CoV-2
9.
Nat Commun ; 11(1): 4131, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807807

RESUMO

Recent outbreaks of viral hemorrhagic fevers (VHFs), including Ebola virus disease (EVD) and Lassa fever (LF), highlight the urgent need for sensitive, deployable tests to diagnose these devastating human diseases. Here we develop CRISPR-Cas13a-based (SHERLOCK) diagnostics targeting Ebola virus (EBOV) and Lassa virus (LASV), with both fluorescent and lateral flow readouts. We demonstrate on laboratory and clinical samples the sensitivity of these assays and the capacity of the SHERLOCK platform to handle virus-specific diagnostic challenges. We perform safety testing to demonstrate the efficacy of our HUDSON protocol in heat-inactivating VHF viruses before SHERLOCK testing, eliminating the need for an extraction. We develop a user-friendly protocol and mobile application (HandLens) to report results, facilitating SHERLOCK's use in endemic regions. Finally, we successfully deploy our tests in Sierra Leone and Nigeria in response to recent outbreaks.


Assuntos
Ebolavirus/patogenicidade , Doença pelo Vírus Ebola/diagnóstico , Febre Lassa/diagnóstico , Vírus Lassa/patogenicidade , Anticorpos Antivirais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Ebolavirus/genética , Doença pelo Vírus Ebola/virologia , Febre Lassa/virologia , Vírus Lassa/genética
10.
bioRxiv ; 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32511415

RESUMO

The COVID-19 pandemic has highlighted that new diagnostic technologies are essential for controlling disease transmission. Here, we develop SHINE (SHERLOCK and HUDSON Integration to Navigate Epidemics), a sensitive and specific integrated diagnostic tool that can detect SARS-CoV-2 RNA from unextracted samples. We combine the steps of SHERLOCK into a single-step reaction and optimize HUDSON to accelerate viral inactivation in nasopharyngeal swabs and saliva. SHINE's results can be visualized with an in-tube fluorescent readout - reducing contamination risk as amplification reaction tubes remain sealed - and interpreted by a companion smartphone application. We validate SHINE on 50 nasopharyngeal patient samples, demonstrating 90% sensitivity and 100% specificity compared to RT-PCR with a sample-to-answer time of 50 minutes. SHINE has the potential to be used outside of hospitals and clinical laboratories, greatly enhancing diagnostic capabilities.

11.
J Mol Diagn ; 21(3): 375-383, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30605765

RESUMO

The clinical management and therapy of many solid tumor malignancies depends on detection of medically actionable or diagnostically relevant genetic variation. However, a principal challenge for genetic assays from tumors is the fragmented and chemically damaged state of DNA in formalin-fixed, paraffin-embedded (FFPE) samples. From highly fragmented DNA and RNA there is no current technology for generating long-range DNA sequence data as is required to detect genomic structural variation or long-range genotype phasing. We have developed a high-throughput chromosome conformation capture approach for FFPE samples that we call Fix-C, which is similar in concept to Hi-C. Fix-C enables structural variation detection from archival FFPE samples. This method was applied to 15 clinical adenocarcinoma- and sarcoma-positive control specimens spanning a broad range of tumor purities. In this panel, Fix-C analysis achieves a 90% concordance rate with fluorescence in situ hybridization assays, the current clinical gold standard. In addition, novel structural variation undetected by other methods could be identified, and long-range chromatin configuration information recovered from these FFPE samples harboring highly degraded DNA. This powerful approach will enable detailed resolution of global genome rearrangement events during cancer progression from FFPE material and will inform the development of targeted molecular diagnostic assays for patient care.


Assuntos
Neoplasias/genética , Inclusão em Parafina/métodos , Fixação de Tecidos/métodos , DNA de Neoplasias/genética , Rearranjo Gênico/genética , Humanos
12.
Curr Biol ; 27(24): 3743-3751.e3, 2017 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-29199073

RESUMO

The theta rhythm-a slow (6-12 Hz) oscillatory component of the local field potential-plays a critical role in spatial navigation and memory by coordinating the activity of neuronal ensembles within the medial temporal lobe (MTL). Although theta has been extensively studied in freely moving rodents, its presence in humans has been elusive and primarily investigated in stationary subjects. Here we used a unique clinical opportunity to examine theta within the human MTL during untethered, real-world ambulatory movement. We recorded intracranial electroencephalographic activity from participants chronically implanted with the wireless NeuroPace responsive neurostimulator (RNS) and tracked their motion with sub-millimeter precision. Our data revealed that movement-related theta oscillations indeed exist in humans, such that theta power is significantly higher during movement than immobility. Unlike in rodents, however, theta occurs in short bouts, with average durations of ∼400 ms, which are more prevalent during fast versus slow movements. In a rare opportunity to study a congenitally blind participant, we found that both the prevalence and duration of theta bouts were increased relative to the sighted participants. These results provide critical support for conserved neurobiological characteristics of theta oscillations during ambulatory spatial navigation, while highlighting some fundamental differences across species in these oscillations between humans and rodents.


Assuntos
Lobo Temporal/fisiologia , Ritmo Teta/fisiologia , Caminhada/fisiologia , Adulto , Eletrocorticografia , Feminino , Humanos , Neuroestimuladores Implantáveis , Masculino , Pessoa de Meia-Idade
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