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1.
Sci Rep ; 13(1): 18008, 2023 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-37865634

RESUMEN

Heart rate (HR) is a crucial physiological signal that can be used to monitor health and fitness. Traditional methods for measuring HR require wearable devices, which can be inconvenient or uncomfortable, especially during sleep and meditation. Noncontact HR detection methods employing microwave radar can be a promising alternative. However, the existing approaches in the literature usually use high-gain antennas and require the sensor to face the user's chest or back, making them difficult to integrate into a portable device and unsuitable for sleep and meditation tracking applications. This study presents a novel approach for noncontact HR detection using a miniaturized Soli radar chip embedded in a portable device (Google Nest Hub). The chip has a [Formula: see text] dimension and can be easily integrated into various devices. The proposed approach utilizes advanced signal processing and machine learning techniques to extract HRs from radar signals. The approach is validated on a sleep dataset (62 users, 498 h) and a meditation dataset (114 users, 1131 min). The approach achieves a mean absolute error (MAE) of 1.69 bpm and a mean absolute percentage error (MAPE) of [Formula: see text] on the sleep dataset. On the meditation dataset, the approach achieves an MAE of 1.05 bpm and a MAPE of [Formula: see text]. The recall rates for the two datasets are [Formula: see text] and [Formula: see text], respectively. This study represents the first application of the noncontact HR detection technology to sleep and meditation tracking, offering a promising alternative to wearable devices for HR monitoring during sleep and meditation.


Asunto(s)
Meditación , Humanos , Frecuencia Cardíaca/fisiología , Sueño , Monitoreo Fisiológico/métodos , Determinación de la Frecuencia Cardíaca
2.
Nat Microbiol ; 8(9): 1634-1640, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37591995

RESUMEN

Timely detection of outbreaks is needed for poliovirus eradication, but gold standard detection in the Democratic Republic of the Congo takes 30 days (median). Direct molecular detection and nanopore sequencing (DDNS) of poliovirus in stool samples is a promising fast method. Here we report prospective testing of stool samples from suspected polio cases, and their contacts, in the Democratic Republic of the Congo between 10 August 2021 and 4 February 2022. DDNS detected polioviruses in 62/2,339 (2.7%) of samples, while gold standard combination of cell culture, quantitative PCR and Sanger sequencing detected polioviruses in 51/2,339 (2.2%) of the same samples. DDNS provided case confirmation in 7 days (median) in routine surveillance conditions. DDNS enabled confirmation of three serotype 2 circulating vaccine-derived poliovirus outbreaks 23 days (mean) earlier (range 6-30 days) than the gold standard method. The mean sequence similarity between sequences obtained by the two methods was 99.98%. Our data confirm the feasibility of implementing DDNS in a national poliovirus laboratory.


Asunto(s)
Secuenciación de Nanoporos , Poliovirus , Poliovirus/genética , Reacción en Cadena de la Polimerasa , Compuestos de Dansilo
3.
Nat Commun ; 13(1): 601, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35105893

RESUMEN

Monitoring SARS-CoV-2 spread and evolution through genome sequencing is essential in handling the COVID-19 pandemic. Here, we sequenced 892 SARS-CoV-2 genomes collected from patients in Saudi Arabia from March to August 2020. We show that two consecutive mutations (R203K/G204R) in the nucleocapsid (N) protein are associated with higher viral loads in COVID-19 patients. Our comparative biochemical analysis reveals that the mutant N protein displays enhanced viral RNA binding and differential interaction with key host proteins. We found increased interaction of GSK3A kinase simultaneously with hyper-phosphorylation of the adjacent serine site (S206) in the mutant N protein. Furthermore, the host cell transcriptome analysis suggests that the mutant N protein produces dysregulated interferon response genes. Here, we provide crucial information in linking the R203K/G204R mutations in the N protein to modulations of host-virus interactions and underline the potential of the nucleocapsid protein as a drug target during infection.


Asunto(s)
COVID-19/virología , Proteínas de la Nucleocápside de Coronavirus/genética , Genoma Viral , Mutación Missense , SARS-CoV-2/genética , COVID-19/enzimología , COVID-19/genética , Proteínas de la Nucleocápside de Coronavirus/metabolismo , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Interacciones Huésped-Patógeno , Humanos , Nucleocápside/genética , Nucleocápside/metabolismo , Fosforilación , Filogenia , Unión Proteica , SARS-CoV-2/clasificación , SARS-CoV-2/fisiología , Arabia Saudita , Carga Viral , Replicación Viral
4.
Nat Commun ; 12(1): 2188, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-33846321

RESUMEN

Unprecedented public health interventions including travel restrictions and national lockdowns have been implemented to stem the COVID-19 epidemic, but the effectiveness of non-pharmaceutical interventions is still debated. We carried out a phylogenetic analysis of more than 29,000 publicly available whole genome SARS-CoV-2 sequences from 57 locations to estimate the time that the epidemic originated in different places. These estimates were examined in relation to the dates of the most stringent interventions in each location as well as to the number of cumulative COVID-19 deaths and phylodynamic estimates of epidemic size. Here we report that the time elapsed between epidemic origin and maximum intervention is associated with different measures of epidemic severity and explains 11% of the variance in reported deaths one month after the most stringent intervention. Locations where strong non-pharmaceutical interventions were implemented earlier experienced much less severe COVID-19 morbidity and mortality during the period of study.


Asunto(s)
COVID-19/diagnóstico , Control de Enfermedades Transmisibles/métodos , Filogenia , Filogeografía/métodos , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/virología , Epidemias , Humanos , Salud Pública/métodos , Salud Pública/estadística & datos numéricos , SARS-CoV-2/clasificación , SARS-CoV-2/fisiología , Índice de Severidad de la Enfermedad
5.
Nature ; 593(7858): 266-269, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33767447

RESUMEN

The SARS-CoV-2 lineage B.1.1.7, designated variant of concern (VOC) 202012/01 by Public Health England1, was first identified in the UK in late summer to early autumn 20202. Whole-genome SARS-CoV-2 sequence data collected from community-based diagnostic testing for COVID-19 show an extremely rapid expansion of the B.1.1.7 lineage during autumn 2020, suggesting that it has a selective advantage. Here we show that changes in VOC frequency inferred from genetic data correspond closely to changes inferred by S gene target failures (SGTF) in community-based diagnostic PCR testing. Analysis of trends in SGTF and non-SGTF case numbers in local areas across England shows that B.1.1.7 has higher transmissibility than non-VOC lineages, even if it has a different latent period or generation time. The SGTF data indicate a transient shift in the age composition of reported cases, with cases of B.1.1.7 including a larger share of under 20-year-olds than non-VOC cases. We estimated time-varying reproduction numbers for B.1.1.7 and co-circulating lineages using SGTF and genomic data. The best-supported models did not indicate a substantial difference in VOC transmissibility among different age groups, but all analyses agreed that B.1.1.7 has a substantial transmission advantage over other lineages, with a 50% to 100% higher reproduction number.


Asunto(s)
COVID-19/transmisión , COVID-19/virología , Filogenia , SARS-CoV-2/clasificación , SARS-CoV-2/patogenicidad , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Número Básico de Reproducción , COVID-19/diagnóstico , COVID-19/epidemiología , Niño , Preescolar , Inglaterra/epidemiología , Evolución Molecular , Genoma Viral/genética , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Glicoproteína de la Espiga del Coronavirus/análisis , Glicoproteína de la Espiga del Coronavirus/genética , Factores de Tiempo , Adulto Joven
6.
Virus Evol ; 7(1): veaa102, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33747543

RESUMEN

Analysis of genetic sequence data from the SARS-CoV-2 pandemic can provide insights into epidemic origins, worldwide dispersal, and epidemiological history. With few exceptions, genomic epidemiological analysis has focused on geographically distributed data sets with few isolates in any given location. Here, we report an analysis of 20 whole SARS- CoV-2 genomes from a single relatively small and geographically constrained outbreak in Weifang, People's Republic of China. Using Bayesian model-based phylodynamic methods, we estimate a mean basic reproduction number (R 0) of 3.4 (95% highest posterior density interval: 2.1-5.2) in Weifang, and a mean effective reproduction number (Rt) that falls below 1 on 4 February. We further estimate the number of infections through time and compare these estimates to confirmed diagnoses by the Weifang Centers for Disease Control. We find that these estimates are consistent with reported cases and there is unlikely to be a large undiagnosed burden of infection over the period we studied.

7.
Cell ; 184(1): 64-75.e11, 2021 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-33275900

RESUMEN

Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant.


Asunto(s)
Sustitución de Aminoácidos , COVID-19/transmisión , COVID-19/virología , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/genética , Ácido Aspártico/análisis , Ácido Aspártico/genética , COVID-19/epidemiología , Genoma Viral , Glicina/análisis , Glicina/genética , Humanos , Mutación , SARS-CoV-2/crecimiento & desarrollo , Reino Unido/epidemiología , Virulencia , Secuenciación Completa del Genoma
8.
Wellcome Open Res ; 5: 81, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32500100

RESUMEN

Background: The COVID-19 epidemic was declared a Global Pandemic by WHO on 11 March 2020. By 24 March 2020, over 440,000 cases and almost 20,000 deaths had been reported worldwide. In response to the fast-growing epidemic, which began in the Chinese city of Wuhan, Hubei, China imposed strict social distancing in Wuhan on 23 January 2020 followed closely by similar measures in other provinces. These interventions have impacted economic productivity in China, and the ability of the Chinese economy to resume without restarting the epidemic was not clear. Methods: Using daily reported cases from mainland China and Hong Kong SAR, we estimated transmissibility over time and compared it to daily within-city movement, as a proxy for economic activity. Results: Initially, within-city movement and transmission were very strongly correlated in the five mainland provinces most affected by the epidemic and Beijing. However, that correlation decreased rapidly after the initial sharp fall in transmissibility. In general, towards the end of the study period, the correlation was no longer apparent, despite substantial increases in within-city movement. A similar analysis for Hong Kong shows that intermediate levels of local activity were maintained while avoiding a large outbreak. At the very end of the study period, when China began to experience the re-introduction of a small number of cases from Europe and the United States, there is an apparent up-tick in transmission. Conclusions: Although these results do not preclude future substantial increases in incidence, they suggest that after very intense social distancing (which resulted in containment), China successfully exited its lockdown to some degree. Elsewhere, movement data are being used as proxies for economic activity to assess the impact of interventions. The results presented here illustrate how the eventual decorrelation between transmission and movement is likely a key feature of successful COVID-19 exit strategies.

9.
Virus Evol ; 6(2): veaa040, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32782825

RESUMEN

Genetic sequencing of polioviruses detected through clinical and environmental surveillance is used to confirm detection, identify their likely origin, track geographic patterns of spread, and determine the appropriate vaccination response. The critical importance of genetic sequencing and analysis to the Global Polio Eradication Initiative has grown with the increasing incidence of vaccine-derived poliovirus (VDPV) infections in Africa specifically (470 reported cases in 2019), and globally, alongside persistent transmission of serotype 1 wild-type poliovirus in Pakistan and Afghanistan (197 reported cases in 2019). Adapting what has been learned about the virus genetics and evolution to address these threats has been a major focus of recent work. Here, we review how phylogenetic and phylogeographic methods have been used to trace the spread of wild-type polioviruses and identify the likely origins of VDPVs. We highlight the analysis methods and sequencing technology currently used and the potential for new technologies to speed up poliovirus detection and the interpretation of genetic data. At a pivotal point in the eradication campaign with the threat of anti-vaccine sentiment and donor and public fatigue, innovation is critical to maintain drive and overcome the last remaining circulating virus.

10.
Science ; 369(6502): 413-422, 2020 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-32532802

RESUMEN

The ongoing coronavirus disease 2019 (COVID-19) pandemic poses a severe threat to public health worldwide. We combine data on demography, contact patterns, disease severity, and health care capacity and quality to understand its impact and inform strategies for its control. Younger populations in lower-income countries may reduce overall risk, but limited health system capacity coupled with closer intergenerational contact largely negates this benefit. Mitigation strategies that slow but do not interrupt transmission will still lead to COVID-19 epidemics rapidly overwhelming health systems, with substantial excess deaths in lower-income countries resulting from the poorer health care available. Of countries that have undertaken suppression to date, lower-income countries have acted earlier. However, this will need to be maintained or triggered more frequently in these settings to keep below available health capacity, with associated detrimental consequences for the wider health, well-being, and economies of these countries.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Países en Desarrollo , Salud Global , Pandemias/prevención & control , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Pobreza , COVID-19 , Infecciones por Coronavirus/transmisión , Humanos , Aceptación de la Atención de Salud , Neumonía Viral/transmisión , Salud Pública
11.
Am J Cardiol ; 123(7): 1019-1025, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30658918

RESUMEN

Previously reported electrocardiographic (ECG) criteria to distinguish left circumflex (LCCA) and right coronary artery (RCA) occlusion in patients with acute inferior ST-segment elevation myocardial infarction (STEMI) afford a modest diagnostic accuracy. We aimed to develop a new algorithm overcoming limitations of previous studies. Clinical, ECG, and coronary angiographic data were analyzed in 230 nonselected patients with acute inferior STEMI who underwent primary percutaneous coronary intervention. A decision-tree analysis was used to develop a new ECG algorithm. The diagnostic accuracy of reported ECG criteria was reviewed. LCCA occlusion occurred in 111 cases and RCA in 119. We developed a 3-step algorithm that identified LCCA and RCA occlusion with a sensitivity of 77%, specificity of 86%, accuracy of 82%, and Youden index of 0.63. The area under the ROC curve was 0.85 and resulted 0.82 after a 10-fold cross validation. The key leads for LCCA occlusion were V3 (ST depression in V3/ST elevation in III >1.2) and V6 (ST elevation ≥0.1 mV or greater than III). The key leads for RCA occlusion were I and aVL (ST depression ≥ 0.1 mV). Fifteen of 21 reviewed studies had less than 20 cases of LCCA occlusion, only 48% performed primary percutaneous coronary intervention, and previous infarction or multivessel disease were often excluded. The diagnostic accuracy of reported ECG criteria decreased when applied to our study population. In conclusion, we report a simple and highly discriminative 3-step ECG algorithm to differentiate LCCA and RCA occlusion in an "all comers" population of patients with acute inferior STEMI. The diagnostic key ECG leads were V3 and V6 for LCCA and I and aVL for RCA occlusion.


Asunto(s)
Algoritmos , Oclusión Coronaria/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Electrocardiografía/métodos , Infarto de la Pared Inferior del Miocardio/diagnóstico , Infarto del Miocardio con Elevación del ST/diagnóstico , Estudios de Casos y Controles , Angiografía Coronaria , Oclusión Coronaria/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Infarto de la Pared Inferior del Miocardio/etiología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Infarto del Miocardio con Elevación del ST/etiología
12.
J Am Coll Surg ; 204(3): 422-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17324776

RESUMEN

BACKGROUND: The tensile strength of running monofilament polypropylene sutures anchored with square knots was compared with the strength of the same size sutures anchored with half hitches. STUDY DESIGN: Polypropylene (Prolene; Ethicon) 0, 2-0, 3-0, 4-0, and 5-0 sutures were secured to a tensionometer with either square knots or half hitches. As tension was applied to the running suture end, the force required to break the suture and the point at which the break occurred were recorded. RESULTS: The sutures anchored with square knots showed only 75% of the strength of the sutures secured with half hitches (p=<0.001). Every suture tied with square knots broke precisely at the point where the last two squared throws invariably tumbled into half hitches with increased tension on the running end. The resulting stress transformation distorted and weakened the suture, as documented by electron microscopy scanning. The sutures secured with half hitches did not show any surface defects, and none of the running sutures tied down with half hitches broke at the knots. CONCLUSIONS: A running polypropylene suture initially anchored with half hitches is stronger and safer than a running suture tied down with square knots.


Asunto(s)
Técnicas de Sutura/instrumentación , Humanos , Técnicas In Vitro , Microscopía Electrónica , Polipropilenos/química , Polipropilenos/normas , Propiedades de Superficie , Técnicas de Sutura/normas , Resistencia a la Tracción
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