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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21250452

RESUMO

Pregnant women appear to be at increased risk for severe outcomes associated with COVID-19, but the pathophysiology underlying this increased morbidity and its potential impact on the developing fetus is not well understood. In this study of pregnant women with and without COVID-19, we assessed viral and immune dynamics at the placenta during maternal SARS-CoV-2 infection. Amongst uninfected women, ACE2 was detected by immunohistochemistry in syncytiotrophoblast cells of the normal placenta during early pregnancy but was rarely seen in healthy placentas at full term. Term placentas from women infected with SARS-CoV-2, however, displayed a significant increase in ACE2 levels. Using immortalized cell lines and primary isolated placental cells, we determined the vulnerability of various placental cell types to direct infection by SARS-CoV-2 in vitro. Yet, despite the susceptibility of placental cells to SARS-CoV-2 infection, viral RNA was detected in the placentas of only a subset ([~]13%) of women in this cohort. Through single cell transcriptomic analyses, we found that the maternal-fetal interface of SARS-CoV-2-infected women exhibited markers associated with pregnancy complications, such as preeclampsia, and robust immune responses, including increased activation of placental NK and T cells and increased expression of interferon-related genes. Overall, this study suggests that SARS-CoV-2 is associated with immune activation at the maternal-fetal interface even in the absence of detectable local viral invasion. While this likely represents a protective mechanism shielding the placenta from infection, inflammatory changes in the placenta may also contribute to poor pregnancy outcomes and thus warrant further investigation.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20183830

RESUMO

Expanding testing capabilities is integral to managing the further spread of SARS-CoV-2 and developing reopening strategies, particularly in regards to identifying and isolating asymptomatic and pre-symptomatic individuals. Central to meeting testing demands are specimens that can be easily and reliably collected and laboratory capacity to rapidly ramp up to scale. We and others have demonstrated that high and consistent levels of SARS-CoV-2 RNA can be detected in saliva from COVID-19 inpatients, outpatients, and asymptomatic individuals. As saliva collection is non-invasive, extending this strategy to test pooled saliva samples from multiple individuals could thus provide a simple method to expand testing capacity. However, hesitation towards pooled sample testing arises due to the dilution of positive samples, potentially shifting weakly positive samples below the detection limit for SARS-CoV-2 and thereby decreasing the sensitivity. Here, we investigated the potential of pooling saliva samples by 5, 10, and 20 samples prior to RNA extraction and RT-qPCR detection of SARS-CoV-2. Based on samples tested, we conservatively estimated a reduction of 7.41%, 11.11%, and 14.81% sensitivity, for each of the pool sizes, respectively. Using these estimates we modeled anticipated changes in RT-qPCR cycle threshold to show the practical impact of pooling on results of SARS-CoV-2 testing. In tested populations with greater than 3% prevalence, testing samples in pools of 5 requires the least overall number of tests. Below 1% however, pools of 10 or 20 are more beneficial and likely more supportive of ongoing surveillance strategies.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20165233

RESUMO

Most currently approved strategies for the collection of saliva for COVID-19 diagnostics require specialized tubes containing buffers promoted for the stabilization of SARS-CoV-2 RNA and virus inactivation. Yet many of these are expensive, in limited supply, and not necessarily validated specifically for viral RNA. While saliva is a promising sample type as it can be reliably self-collected for the sensitive detection of SARS-CoV-2, the expense and availability of these collection tubes are prohibitive to mass testing efforts. Therefore, we investigated the stability of SARS-CoV-2 RNA and infectious virus detection from saliva without supplementation. We tested RNA stability over extended periods of time (2-25 days) and at temperatures representing at-home storage and elevated temperatures which might be experienced when cold chain transport may be unavailable. We found SARS-CoV-2 RNA in saliva from infected individuals is stable at 4{degrees}C, room temperature ([~]19{degrees}C), and 30{degrees}C for prolonged periods and found limited evidence for viral replication in stored saliva samples. This work demonstrates that expensive saliva collection options involving RNA stabilization and virus inactivation buffers are not always needed, permitting the use of cheaper collection options. Affordable testing methods are urgently needed to meet current testing demands and for continued surveillance in reopening strategies.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20167791

RESUMO

Current bottlenecks for improving accessibility and scalability of SARS-CoV-2 testing include diagnostic assay costs, complexity, and supply chain shortages. To resolve these issues, we developed SalivaDirect, which received Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration on August 15th, 2020. The critical component of our approach is to use saliva instead of respiratory swabs, which enables non-invasive frequent sampling and reduces the need for trained healthcare professionals during collection. Furthermore, we simplified our diagnostic test by (1) not requiring nucleic acid preservatives at sample collection, (2) replacing nucleic acid extraction with a simple proteinase K and heat treatment step, and (3) testing specimens with a dualplex quantitative reverse transcription PCR (RT-qPCR) assay. We validated SalivaDirect with reagents and instruments from multiple vendors to minimize the risk for supply chain issues. Regardless of our tested combination of reagents and instruments from different vendors, we found that SalivaDirect is highly sensitive with a limit of detection of 6-12 SARS-CoV-2 copies/L. When comparing SalivaDirect to paired nasopharyngeal swabs using the authorized ThermoFisher Scientific TaqPath COVID-19 combo kit, we found high agreement in testing outcomes (>94%). In partnership with the National Basketball Association (NBA) and Players Association, we conducted a large-scale (n = 3,779) SalivaDirect usability study and comparison to standard nasal/oral tests for asymptomatic and presymptomatic SARS-CoV-2 detection. From this cohort of healthy NBA players, staff, and contractors, we found that 99.7% of samples were valid using our saliva collection techniques and a 89.5% positive and >99.9% negative test agreement to swabs, demonstrating that saliva is a valid and noninvasive alternative to swabs for large-scale SARS-CoV-2 testing. SalivaDirect is a flexible and inexpensive ($1.21-$4.39/sample in reagent costs) option to help improve SARS-CoV-2 testing capacity. Register to become a designated laboratory to use SalivaDirect under our FDA EUA on our website: publichealth.yale.edu/salivadirect/.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20153437

RESUMO

A dysregulated immune response against the SARS-CoV-2 virus plays a critical role in severe COVID-19. However, the molecular and cellular mechanisms by which the virus causes lethal immunopathology are poorly understood. Here, we utilize multiomics single-cell analysis to probe dynamic immune responses in patients with stable or progressive manifestations of COVID-19, and assess the effects of tocilizumab, an anti-IL-6 receptor monoclonal antibody. Coordinated profiling of gene expression and cell lineage protein markers reveals a prominent type-1 interferon response across all immune cells, especially in progressive patients. An anti-inflammatory innate immune response and a pre-exhaustion phenotype in activated T cells are hallmarks of progressive disease. Skewed T cell receptor repertoires in CD8+ T cells and uniquely enriched V(D)J sequences are also identified in COVID-19 patients. B cell repertoire and somatic hypermutation analysis are consistent with a primary immune response, with possible contribution from memory B cells. Our in-depth immune profiling reveals dyssynchrony of the innate and adaptive immune interaction in progressive COVID-19, which may contribute to delayed virus clearance and has implications for therapeutic intervention.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20149849

RESUMO

Introductory ParagraphThe COVID-19 pandemic has affected more than 10 million people worldwide with mortality exceeding half a million patients. Risk factors associated with severe disease and mortality include advanced age, hypertension, diabetes, and obesity.1 Clear mechanistic understanding of how these comorbidities converge to enable severe infection is lacking. Notably each of these risk factors pathologically disrupts the lipidome and this disruption may be a unifying feature of severe COVID-19.1-7 Here we provide the first in depth interrogation of lipidomic changes, including structural-lipids as well as the eicosanoids and docosanoids lipid mediators (LMs), that mark COVID-19 disease severity. Our data reveal that progression from moderate to severe disease is marked by a loss of specific immune regulatory LMs and increased pro-inflammatory species. Given the important immune regulatory role of LMs, these data provide mechanistic insight into the immune balance in COVID-19 and potential targets for therapy with currently approved pharmaceuticals.8

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20070102

RESUMO

Seasonal influenza (flu) is an underappreciated source of disease morbidity and mortality worldwide. While vaccination remains the cornerstone of influenza prevention, common measures practiced during the COVID-19 pandemic such as social distancing, the use of protective face masks, and frequent hand washing are rarely utilized during flu season. In this investigation, we examined the effect of these preventative measures in decreasing influenza burden this year. We examined three countries with major COVID-19 outbreaks i.e. China, Italy and the United States, and compared the flu activity this year to the average of the last 4 years (2015-2019). We found that this year in China and Italy, there was a significantly steeper decline of flu cases than average, which correlated with an increase in positive COVID-19 case reports in those countries. These "averted" cases can be translated into a substantial decrease in morbidity and mortality. As such, we conclude that the current COVID-19 pandemic is a reminder that behavioral measures can decrease the burden of communicable respiratory infections, and these measures should be adopted to an extent during normal influenza season.

8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20067835

RESUMO

Rapid and accurate SARS-CoV-2 diagnostic testing is essential for controlling the ongoing COVID-19 pandemic. The current gold standard for COVID-19 diagnosis is real-time RT-PCR detection of SARS-CoV-2 from nasopharyngeal swabs. Low sensitivity, exposure risks to healthcare workers, and global shortages of swabs and personal protective equipment, however, necessitate the validation of new diagnostic approaches. Saliva is a promising candidate for SARS-CoV-2 diagnostics because (1) collection is minimally invasive and can reliably be self-administered and (2) saliva has exhibited comparable sensitivity to nasopharyngeal swabs in detection of other respiratory pathogens, including endemic human coronaviruses, in previous studies. To validate the use of saliva for SARS-CoV-2 detection, we tested nasopharyngeal and saliva samples from confirmed COVID-19 patients and self-collected samples from healthcare workers on COVID-19 wards. When we compared SARS-CoV-2 detection from patient-matched nasopharyngeal and saliva samples, we found that saliva yielded greater detection sensitivity and consistency throughout the course of infection. Furthermore, we report less variability in self-sample collection of saliva. Taken together, our findings demonstrate that saliva is a viable and more sensitive alternative to nasopharyngeal swabs and could enable at-home self-administered sample collection for accurate large-scale SARS-CoV-2 testing.

9.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20048108

RESUMO

The recent spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exemplifies the critical need for accurate and rapid diagnostic assays to prompt clinical and public health interventions. Currently, several quantitative reverse-transcription polymerase chain reaction (qRT-PCR) assays are being used by clinical, research, and public health laboratories. However, it is currently unclear if results from different tests are comparable. Our goal was to evaluate the primer-probe sets used in four common diagnostic assays available on the World Health Organization (WHO) website. To facilitate this effort, we generated RNA transcripts to be used as assay standards and distributed them to other laboratories for internal validation. We then used (1) RNA transcript standards, (2) full-length SARS-CoV-2 RNA, (3) pre-COVID-19 nasopharyngeal swabs, and (4) clinical samples from COVID-19 patients to determine analytical efficiency and sensitivity of the qRT-PCR primer-probe sets. We show that all primer-probe sets can be used to detect SARS-CoV-2 at 500 virus copies per reaction, except for the RdRp-SARSr (Charite) confirmatory primer-probe set which has low sensitivity. Our findings characterize the limitations of currently used primer-probe sets and can assist other laboratories in selecting appropriate assays for the detection of SARS-CoV-2.

10.
Inf. psiquiátr ; (231): 85-96, ene.-mar. 2018. graf
Artigo em Espanhol | IBECS | ID: ibc-173280

RESUMO

Actualmente, la evolución de la atención a las personas con trastorno mental grave está avanzando hacia un modelo social. Esta evolución está amparada por las leyes y normativas vigentes así como numerosos estudios que avalan una práctica centrada en la persona, en sus capacidades y en el modelo de recuperación. En el presente trabajo se ejemplifica un modelo de trabajo, donde el desempeño del rol de voluntario, con sus diferentes niveles y apoyos, hace posible que las personas con TMG puedan elegir un proyecto de vida consecuente con sus valores y con su derecho a participar socialmente como ciudadanos de pleno derecho


Currently, the evolution of care for people with mental disorder has being developed from a social model. This evolution is guide by laws and regulations in force. In addition, numerous studies support a practice focused on the person, their capabilities and the recovery model. The present article exemplifies a work model where the performance of the volunteer role, with its different levels and supports, makes it possible for people with mental disorder can choose their life projects. These life projects are consistent with their values and their right to participate socially as full citizens


Assuntos
Humanos , Assistência à Saúde Mental , Transtornos Mentais/reabilitação , Trabalhadores Voluntários de Hospital/psicologia , Centros Comunitários de Saúde Mental/organização & administração , Participação Social/psicologia
11.
Inf. psiquiátr ; (222): 71-77, oct.-dic. 2015. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-147990

RESUMO

El artículo recoge la experiencia de un grupo de personas con enfermedad mental grave y/o duradera, usuarias del Centro de Día Aravaca, que deciden ser voluntarias y ofrecer servicios a la comunidad. Tras la exploración de intereses relacionados con el ámbito de voluntariado se tomó la decisión de realizar un voluntariado en actividades relacionadas con el cuidado de los animales y la naturaleza. Tras una importante búsqueda de recursos pudimos conocer el espacio donde hoy realizamos la actividad: Burrolandia, única reserva de burros de la Comunidad de Madrid. En las instalaciones de esta asociación y junto a los profesionales de la misma, es donde se desarrolla la actividad en su totalidad, obteniendo beneficios importantes en el proceso de rehabilitación psicosocial de los usuarios que participan como voluntarios de la organización


The article describes the experiences of a group of people with severe mental illness. These people are users of Aravaca Day Center. They decided to volunteer and provide community services. After the exploration of interest we choose to do a voluntary service to the care of animals and nature. After making an important resource search, we found the place where voluntary activity is doing today: Burrolandia, the unique nonprofits association in Madrid, whose main objective is to prevent the extinction of donkeys. The activity has been done at Burrolandia`s facilities under their staff supervision. Users who are volunteers in the organization have made significant gains in the process or psychosocial rehabilitation


Assuntos
Humanos , Transtornos Mentais/reabilitação , Voluntários , Terapia Ocupacional/organização & administração , Bem-Estar do Animal , Participação Social
12.
Inf. psiquiátr ; (214): 435-448, sept.-dic. 2013. ilus
Artigo em Espanhol | IBECS | ID: ibc-131352

RESUMO

El artículo recoge la experiencia en el Centro de Día de Soporte Social para personas con Enfermedad Mental Grave y Duradera del distrito Moncloa-Aravaca, perteneciente a la Congregación Hermanas Hospitalarias. Debido al alto porcentaje de personas en situación sin hogar que son usuarios del centro, ha sido necesario adaptarse con mayor exactitud a sus necesidades y ser especialmente flexibles con sus tiempos de adaptación, tanto a los profesionales del Centro de Día (aceptarlos como figura de referencia), como al propio funcionamiento del Centro, y el modo de relacionarse con sus compa-ñeros, totalmente distinto a lo que están acostumbrados. Esta forma de intervención ha facilitado que personas con enfermedad mental y que además están en situación sin hogar, hayan retomado en mayor medida el control sobre sus propias vidas. Se exponen las dificultades encontradas a la hora de trabajar con esta población y las claves para facilitar el éxito del trabajo personal y la consecución de los objetivos vitales que se plantean. Del mismo modo, se ha tenido en cuenta la influencia del doble estigma asociado a estas personas y su impacto en su integración comunitaria (AU)


This paper describes the experiences at the Center for Social Support for People with Mental Illness at Moncloa-Aravacadistrict, property of the Hermanas Hospitalarias. Due to the high percentage of people experiencing homelessness who are users of the center, it has been necessary to be more adaptable, and be especially flexible with time of adaptation, both professionals (accept them as a reference figure), as to the center operation, and the way they relate to their peers, totally different from what they are used to. This way of intervention has enabled people with mental illness who are also homeless situation, to have taken back control over their own lives. Authors describe the difficulties encountered when working with homeless people and the keys to facilitate the success of personal work and achieving life goals. They also take into account the influence of the double stigma attached to these people, and the impact it has on its community integration (AU)


Assuntos
Humanos , Carência Psicossocial , Transtornos Mentais/reabilitação , Estigma Social , Pessoas Mal Alojadas/psicologia , Apoio Social , População Institucionalizada
13.
Environ Int ; 29(1): 69-77, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12605939

RESUMO

The presence of heavy metal concentrations was examined in surface sediments from 27 sites within the Odiel river in the southwest Spain suffering inputs from industrial and mining activities. The interest is specially focused on the final delta located in the Odiel Natural Park, which constitutes a feeding ground of international importance for migrating birds. The behavior of 10 heavy metals (Zn, Cd, Pb, Cu, Cr, Mn, Ni, Fe, Hg) is conditioned by chemical properties of sediments such as acidity and carbonate or the presence of sulfate Very acidic sediments in the medium course of river contribute to the lower presence of metal as a consequence of leaching process. However, tidal action raises the pH in the marshes of the delta with correlative metal accumulation. In accordance with the Müller [Umschan 79 (1979) 133-149] scale for geoaccumulation index, the entire watercourse could be considered polluted by Zn and Pb, while Cu exhibits a high presence in the delta marshes of the river.


Assuntos
Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes da Água/análise , Animais , Aves , Dieta , Monitoramento Ambiental , Medição de Risco , Espanha
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