Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 322
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Nat Immunol ; 20(7): 928-942, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31061532

RESUMEN

To define the cell populations that drive joint inflammation in rheumatoid arthritis (RA), we applied single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq) and flow cytometry to T cells, B cells, monocytes, and fibroblasts from 51 samples of synovial tissue from patients with RA or osteoarthritis (OA). Utilizing an integrated strategy based on canonical correlation analysis of 5,265 scRNA-seq profiles, we identified 18 unique cell populations. Combining mass cytometry and transcriptomics revealed cell states expanded in RA synovia: THY1(CD90)+HLA-DRAhi sublining fibroblasts, IL1B+ pro-inflammatory monocytes, ITGAX+TBX21+ autoimmune-associated B cells and PDCD1+ peripheral helper T (TPH) cells and follicular helper T (TFH) cells. We defined distinct subsets of CD8+ T cells characterized by GZMK+, GZMB+, and GNLY+ phenotypes. We mapped inflammatory mediators to their source cell populations; for example, we attributed IL6 expression to THY1+HLA-DRAhi fibroblasts and IL1B production to pro-inflammatory monocytes. These populations are potentially key mediators of RA pathogenesis.


Asunto(s)
Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Perfilación de la Expresión Génica , Membrana Sinovial/metabolismo , Transcriptoma , Artritis Reumatoide/patología , Autoinmunidad/genética , Biomarcadores , Biología Computacional/métodos , Estudios Transversales , Citocinas/metabolismo , Fibroblastos/metabolismo , Citometría de Flujo , Expresión Génica , Perfilación de la Expresión Génica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos , Leucocitos/inmunología , Leucocitos/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , Transducción de Señal , Análisis de la Célula Individual/métodos , Membrana Sinovial/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Flujo de Trabajo
2.
Nature ; 626(7998): 306-312, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38326593

RESUMEN

Rechargeable Li-metal batteries have the potential to more than double the specific energy of the state-of-the-art rechargeable Li-ion batteries, making Li-metal batteries a prime candidate for next-generation high-energy battery technology1-3. However, current Li-metal batteries suffer from fast cycle degradation compared with their Li-ion battery counterparts2,3, preventing their practical adoption. A main contributor to capacity degradation is the disconnection of Li from the electrochemical circuit, forming isolated Li4-8. Calendar ageing studies have shown that resting in the charged state promotes further reaction of active Li with the surrounding electrolyte9-12. Here we discover that calendar ageing in the discharged state improves capacity retention through isolated Li recovery, which is in contrast with the well-known phenomenon of capacity degradation observed during the charged state calendar ageing. Inactive capacity recovery is verified through observation of Coulombic efficiency greater than 100% on both Li||Cu half-cells and anode-free cells using a hybrid continuous-resting cycling protocol and with titration gas chromatography. An operando optical setup further confirms excess isolated Li reactivation as the predominant contributor to the increased capacity recovery. These insights into a previously unknown pathway for capacity recovery through discharged state resting emphasize the marked impact of cycling strategies on Li-metal battery performance.

3.
Nature ; 600(7890): 659-663, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34937896

RESUMEN

The increasing demand for next-generation energy storage systems necessitates the development of high-performance lithium batteries1-3. Unfortunately, current Li anodes exhibit rapid capacity decay and a short cycle life4-6, owing to the continuous generation of solid electrolyte interface7,8 and isolated Li (i-Li)9-11. The formation of i-Li during the nonuniform dissolution of Li dendrites12 leads to a substantial capacity loss in lithium batteries under most testing conditions13. Because i-Li loses electrical connection with the current collector, it has been considered electrochemically inactive or 'dead' in batteries14,15. Contradicting this commonly accepted presumption, here we show that i-Li is highly responsive to battery operations, owing to its dynamic polarization to the electric field in the electrolyte. Simultaneous Li deposition and dissolution occurs on two ends of the i-Li, leading to its spatial progression toward the cathode (anode) during charge (discharge). Revealed by our simulation results, the progression rate of i-Li is mainly affected by its length, orientation and the applied current density. Moreover, we successfully demonstrate the recovery of i-Li in Cu-Li cells with >100% Coulombic efficiency and realize LiNi0.5Mn0.3Co0.2O2 (NMC)-Li full cells with extended cycle life.

4.
Proc Natl Acad Sci U S A ; 120(10): e2214357120, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36848560

RESUMEN

Improving Coulombic efficiency (CE) is key to the adoption of high energy density lithium metal batteries. Liquid electrolyte engineering has emerged as a promising strategy for improving the CE of lithium metal batteries, but its complexity renders the performance prediction and design of electrolytes challenging. Here, we develop machine learning (ML) models that assist and accelerate the design of high-performance electrolytes. Using the elemental composition of electrolytes as the features of our models, we apply linear regression, random forest, and bagging models to identify the critical features for predicting CE. Our models reveal that a reduction in the solvent oxygen content is critical for superior CE. We use the ML models to design electrolyte formulations with fluorine-free solvents that achieve a high CE of 99.70%. This work highlights the promise of data-driven approaches that can accelerate the design of high-performance electrolytes for lithium metal batteries.

5.
Histopathology ; 84(5): 847-862, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38233108

RESUMEN

AIMS: To conduct a definitive multicentre comparison of digital pathology (DP) with light microscopy (LM) for reporting histopathology slides including breast and bowel cancer screening samples. METHODS: A total of 2024 cases (608 breast, 607 GI, 609 skin, 200 renal) were studied, including 207 breast and 250 bowel cancer screening samples. Cases were examined by four pathologists (16 study pathologists across the four speciality groups), using both LM and DP, with the order randomly assigned and 6 weeks between viewings. Reports were compared for clinical management concordance (CMC), meaning identical diagnoses plus differences which do not affect patient management. Percentage CMCs were computed using logistic regression models with crossed random-effects terms for case and pathologist. The obtained percentage CMCs were referenced to 98.3% calculated from previous studies. RESULTS: For all cases LM versus DP comparisons showed the CMC rates were 99.95% [95% confidence interval (CI) = 99.90-99.97] and 98.96 (95% CI = 98.42-99.32) for cancer screening samples. In speciality groups CMC for LM versus DP showed: breast 99.40% (99.06-99.62) overall and 96.27% (94.63-97.43) for cancer screening samples; [gastrointestinal (GI) = 99.96% (99.89-99.99)] overall and 99.93% (99.68-99.98) for bowel cancer screening samples; skin 99.99% (99.92-100.0); renal 99.99% (99.57-100.0). Analysis of clinically significant differences revealed discrepancies in areas where interobserver variability is known to be high, in reads performed with both modalities and without apparent trends to either. CONCLUSIONS: Comparing LM and DP CMC, overall rates exceed the reference 98.3%, providing compelling evidence that pathologists provide equivalent results for both routine and cancer screening samples irrespective of the modality used.


Asunto(s)
Neoplasias de la Mama , Neoplasias Colorrectales , Patología Clínica , Humanos , Detección Precoz del Cáncer , Interpretación de Imagen Asistida por Computador/métodos , Microscopía/métodos , Patología Clínica/métodos , Femenino , Estudios Multicéntricos como Asunto
6.
J Am Chem Soc ; 145(22): 12342-12350, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37220230

RESUMEN

At >95% Coulombic efficiencies, most of the capacity loss for Li metal anodes (LMAs) is through the formation and growth of the solid electrolyte interphase (SEI). However, the mechanism through which this happens remains unclear. One property of the SEI that directly affects its formation and growth is the SEI's solubility in the electrolyte. Here, we systematically quantify and compare the solubility of SEIs derived from ether-based electrolytes optimized for LMAs using in-operando electrochemical quartz crystal microbalance (EQCM). A correlation among solubility, passivity, and cyclability established in this work reveals that SEI dissolution is a major contributor to the differences in passivity and electrochemical performance among battery electrolytes. Together with our EQCM, X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (NMR) spectroscopy results, we show that solubility depends on not only the SEI's composition but also the properties of the electrolyte. This provides a crucial piece of information that could help minimize capacity loss due to SEI formation and growth during battery cycling and aging.

7.
Nat Mater ; 21(4): 445-454, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35039645

RESUMEN

Designing a stable solid-electrolyte interphase on a Li anode is imperative to developing reliable Li metal batteries. Herein, we report a suspension electrolyte design that modifies the Li+ solvation environment in liquid electrolytes and creates inorganic-rich solid-electrolyte interphases on Li. Li2O nanoparticles suspended in liquid electrolytes were investigated as a proof of concept. Through theoretical and empirical analyses of Li2O suspension electrolytes, the roles played by Li2O in the liquid electrolyte and solid-electrolyte interphases of the Li anode are elucidated. Also, the suspension electrolyte design is applied in conventional and state-of-the-art high-performance electrolytes to demonstrate its applicability. Based on electrochemical analyses, improved Coulombic efficiency (up to ~99.7%), reduced Li nucleation overpotential, stabilized Li interphases and prolonged cycle life of anode-free cells (~70 cycles at 80% of initial capacity) were achieved with the suspension electrolytes. We expect this design principle and our findings to be expanded into developing electrolytes and solid-electrolyte interphases for Li metal batteries.


Asunto(s)
Suministros de Energía Eléctrica , Litio , Electrodos , Electrólitos
8.
J Immunol ; 206(6): 1194-1203, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33579724

RESUMEN

We described a human regulatory T cell (Treg) population activated by IgG+ B cells presenting peptides of the heavy C region (Fc) via processing of the surface IgG underlying a model for B cell-Treg cooperation in the human immune regulation. Functionally, Treg inhibited the polarization of naive T cells toward a proinflammatory phenotype in both a cognate and a noncognate fashion. Their fine specificities were similar in healthy donors and patients with rheumatoid arthritis, a systemic autoimmune disease. Four immunodominant Fc peptides bound multiple HLA class II alleles and were recognized by most subjects in the two cohorts. The presentation of Fc peptides that stimulate Treg through the processing of IgG by dendritic cells (DC) occurred in myeloid DC classical DC 1 and classical DC 2. Different routes of Ag processing of the IgG impacted Treg expansion in rheumatoid arthritis patients.


Asunto(s)
Artritis Reumatoide/inmunología , Epítopos de Linfocito B/inmunología , Fragmentos Fc de Inmunoglobulinas/inmunología , Inmunoglobulina G/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Presentación de Antígeno , Artritis Reumatoide/sangre , Células Dendríticas/inmunología , Femenino , Antígenos de Histocompatibilidad Clase II/inmunología , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Fragmentos Fc de Inmunoglobulinas/metabolismo , Inmunoglobulina G/metabolismo , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Cultivo Primario de Células , Adulto Joven
9.
Proc Natl Acad Sci U S A ; 117(47): 29453-29461, 2020 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-33168752

RESUMEN

Rechargeability and operational safety of commercial lithium (Li)-ion batteries demand further improvement. Plating of metallic Li on graphite anodes is a critical reason for Li-ion battery capacity decay and short circuit. It is generally believed that Li plating is caused by the slow kinetics of graphite intercalation, but in this paper, we demonstrate that thermodynamics also serves a crucial role. We show that a nonuniform temperature distribution within the battery can make local plating of Li above 0 V vs. Li0/Li+ (room temperature) thermodynamically favorable. This phenomenon is caused by temperature-dependent shifts of the equilibrium potential of Li0/Li+ Supported by simulation results, we confirm the likelihood of this failure mechanism during commercial Li-ion battery operation, including both slow and fast charging conditions. This work furthers the understanding of nonuniform Li plating and will inspire future studies to prolong the cycling lifetime of Li-ion batteries.

10.
Ecotoxicol Environ Saf ; 253: 114613, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36796205

RESUMEN

The mechanisms of toxicity of engineered nanomaterials (ENMs) to the early life stages of freshwater fish, and the relative hazard compared to dissolved metals, is only partially understood. In the present study, zebrafish embryos were exposed to lethal concentrations of copper sulphate (CuSO4) or copper oxide (CuO) ENMs (primary size ∼15 nm), and then the sub-lethal effects investigated at the LC10 concentrations over 96 h. The 96 h-LC50 (mean ± 95% CI) for CuSO4 was 303 ± 14 µg Cu L-1 compared to 53 ± 9.9 mg L-1 of the whole material for CuO ENMs; with the ENMs being orders of magnitude less toxic than the metal salt. The EC50 for hatching success was 76 ± 11 µg Cu L-1 and 0.34 ± 0.78 mg L-1 for CuSO4 and CuO ENMs respectively. Failure to hatch was associated with bubbles and foam-looking perivitelline fluid (CuSO4), or particulate material smothering the chorion (CuO ENMs). In the sub-lethal exposures, about 42% of the total Cu as CuSO4 was internalised, as measured by Cu accumulation in the de-chorionated embryos, but for the ENMs exposures, nearly all (94%) of the total Cu was associated with chorion; indicating the chorion as an effective barrier to protect the embryo from the ENMs in the short term. Both forms of Cu exposure caused sodium (Na+) and calcium (Ca2+), but not magnesium (Mg2+), depletion from the embryos; and CuSO4 caused some inhibition of the sodium pump (Na+/K+-ATPase) activity. Both forms of Cu exposure caused some loss of total glutathione (tGSH) in the embryos, but without induction of superoxide dismutase (SOD) activity. In conclusion, CuSO4 was much more toxic than CuO ENMs to early life stage zebrafish, but there are subtle differences in the exposure and toxic mechanisms for each substance.


Asunto(s)
Nanoestructuras , Contaminantes Químicos del Agua , Animales , Cobre/toxicidad , Cobre/análisis , Sulfato de Cobre/toxicidad , Pez Cebra , Nanoestructuras/toxicidad , Óxidos , Contaminantes Químicos del Agua/toxicidad
11.
Nano Lett ; 22(20): 8224-8232, 2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36214378

RESUMEN

Poor fast-charge capabilities limit the usage of rechargeable Li metal anodes. Understanding the connection between charging rate, electroplating mechanism, and Li morphology could enable fast-charging solutions. Here, we develop a combined electroanalytical and nanoscale characterization approach to resolve the current-dependent regimes of Li plating mechanisms and morphology. Measurement of Li+ transport through the solid electrolyte interphase (SEI) shows that low currents induce plating at buried Li||SEI interfaces, but high currents initiate SEI-breakdown and plating at fresh Li||electrolyte interfaces. The latter pathway can induce uniform growth of {110}-faceted Li at extremely high currents, suggesting ion-transport limitations alone are insufficient to predict Li morphology. At battery relevant fast-charging rates, SEI-breakdown above a critical current density produces detrimental morphology and poor cyclability. Thus, prevention of both SEI-breakdown and slow ion-transport in the electrolyte is essential. This mechanistic insight can inform further electrolyte engineering and customization of fast-charging protocols for Li metal batteries.

12.
J Am Chem Soc ; 144(45): 20717-20725, 2022 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-36318744

RESUMEN

The rechargeability of lithium metal batteries strongly depends on the electrolyte. The uniformity of the electroplated Li anode morphology underlies this dependence, so understanding the main drivers of uniform plating is critical for further electrolyte discovery. Here, we correlate electroplating kinetics with cyclability across several classes of electrolytes to reveal the mechanistic influence electrolytes have on morphology. Fast charge-transfer kinetics at fresh Li-electrolyte interfaces correlate well with uniform morphology and cyclability, whereas the resistance of Li+ transport through the solid electrolyte interphase (SEI) weakly correlates with cyclability. These trends contrast with the conventional thought that Li+ transport through the electrolyte or SEI is the main driver of morphological differences between classes of electrolytes. Relating these trends to Li+ solvation, Li nucleation, and the charge-transfer mechanism instead suggests that the Li/Li+ equilibrium potential and the surface energy─thermodynamic factors modulated by the strength of Li+ solvation─underlie electrolyte-dependent trends of Li morphology. Overall, this work provides an insight for discovering functional electrolytes, tuning kinetics in batteries, and explaining why weakly solvating fluorinated electrolytes favor uniform Li plating.


Asunto(s)
Electrólitos , Litio , Cinética , Electrodos , Iones , Termodinámica
13.
Phys Chem Chem Phys ; 24(38): 23884-23892, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36165463

RESUMEN

Gold-based catalysts have received tremendous attention as supports and nanoparticles for heterogeneous catalysis, in part due to the ability of nanoscale Au to catalyze reactions at low temperatures in oxidative environments. Surface defects are known active sites for low temperature Au chemistry, so a full understanding of the interplay between intermolecular interactions and surface morphology is essential to an advanced understanding of catalytic behavior and efficiency. In a systematic study to better understand the adsorption and intermolecular behavior of small alcohols (C1-C4) on Au(111) defect sites, coverage studies of methanol, ethanol, 1-propanol, 1-butanol, 2-butanol, and isobutanol have been conducted on Au(111) using ultrahigh vacuum temperature programmed desorption (UHV-TPD). These small alcohols molecularly adsorb on the Au(111) surface and high resolution experiments reveal distinct terrace, step edge, and kink adsorption features for each molecule. The hydrogen-bonded (H-bonded) networks of small alcohols on Au(111), except for 1-butanol and isobutanol, have been previously imaged on the molecular level at low temperatures by scanning tunneling microscopy. Primary C1-C3 alcohols exhibit planar H-bonded long extended zigzag chain networks while 2-butanol arranges in tetramer clusters of H-bonded molecules due to steric hindrance inhibiting the proximity of molecules on Au(111). Herein, the desorption energy of small primary alcohols was shown to trend linearly with increasing C1-C4 carbon chain length, indicating that the H-bonded molecular packing of 1-butanol resembles that of methanol, ethanol, and 1-propanol, while isobutanol and 2-butanol deviate from the trend. Butanol isomer studies allow the prediction of isobutanol long extended chains in contrast to tetramers. The distinction between the desorption of butanol isomers highlights the role of intermolecular interactions due to the difference in molecular packing structures on Au(111). Furthermore, by studying the energetics of terrace H-bonded networks in comparison with molecular adsorption at undercoordinated step edge and kink defect sites, it is shown that the contribution of stabilizing van der Waals forces to the overall adsorption energy is less for small alcohols adsorbed at kink sites (3.1 kJ mol-1 per CH2) and similar for those adsorbed at step edge (4.8 kJ mol-1 per CH2) and Au terrace sites (4.9 kJ mol-1 per CH2).

14.
Pediatr Crit Care Med ; 23(4): e219-e223, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34991139

RESUMEN

OBJECTIVES: With decreasing PICU mortality, survivor morbidity has increased. This study aims to evaluate feasibility of virtual PICU-led follow-up of patients at risk for pediatric postintensive care syndrome. DESIGN: Prospective cohort study. SETTING: Single-center, quaternary children's hospital. PATIENTS: Children less than or equal to 4 years without known preexisting neurodevelopmental deficits requiring greater than or equal to 12 hours mechanical ventilation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Age-appropriate Ages and Stages Questionnaires, Third Edition (ASQ-3) were administered via a web-based system at 3, 6, and 12 months following PICU discharge. Primary-care physicians were notified of results; at-risk patients were referred to early developmental intervention. Forty-eight patients enrolled with median age 11.5 months (interquartile range [IQR], 2-19.5 mo) and median mechanical ventilation duration 92.5 hours (IQR, 40.5-147 hr). Fifty-eight percent completed greater than or equal to 1 ASQ-3. Lower caregiver educational achievement, lower income, and single-caregiver status were associated with lower ASQ-3 completion rates. Of those completing any ASQ-3, 50% flagged as at-risk for developmental delay and referred to early developmental intervention. There was no association between patient characteristics and abnormal ASQ-3. CONCLUSIONS: Virtual caregiver-completed surveillance is a promising method to screen children for neurodevelopmental abnormalities following PICU hospitalization and facilitate early referral for developmental intervention, but special attention must be dedicated to families with limited resources for follow-up.


Asunto(s)
Enfermedad Crítica , Respiración Artificial , Niño , Humanos , Lactante , Unidades de Cuidado Intensivo Pediátrico , Proyectos Piloto , Estudios Prospectivos , Psicometría , Respiración Artificial/efectos adversos
15.
Regul Toxicol Pharmacol ; 130: 105125, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35085603

RESUMEN

Cobalt occurs naturally in the earth's crust, is essential to some microorganisms and forms the core of vitamin B12. Cobalt substances are used in numerous technologies, such as catalysts or batteries. Some of these substances are classified as Carcinogens, while other cobalt compounds have a hazard profile that is less understood and are missing long term studies like cancer bioassays. There is a strong interest by society and industry to reduce and -where possible- eliminate animal testing, yet a necessity by industry and authorities to have sufficient data for hazard conclusions and risk assessments. The present paper introduces a strategy for a mode of action-informed tiered testing, aimed at full inclusion of existing hazard data and selection of relevant biological events towards a certain adverse outcome, i.e. inhalation carcinogenicity. The occurrence of these events following exposure to various cobalt substances is investigated with in vitro and with limited in vivo testing. The tiers of testing are described in the companion papers of this RTP special issue. This approach has given rise to the formulation of two distinct groups, containing substances with similar properties, that can be addressed with limited higher tier animal testing and read across of in vivo results.


Asunto(s)
Cobalto/toxicidad , Alternativas a las Pruebas en Animales , Cobalto/farmacocinética , Técnicas In Vitro , Exposición por Inhalación , Valores de Referencia , Medición de Riesgo , Pruebas de Toxicidad
16.
J Am Chem Soc ; 143(27): 10301-10308, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34184873

RESUMEN

The electrolyte plays a critical role in lithium-ion batteries, as it impacts almost every facet of a battery's performance. However, our understanding of the electrolyte, especially solvation of Li+, lags behind its significance. In this work, we introduce a potentiometric technique to probe the relative solvation energy of Li+ in battery electrolytes. By measuring open circuit potential in a cell with symmetric electrodes and asymmetric electrolytes, we quantitatively characterize the effects of concentration, anions, and solvents on solvation energy across varied electrolytes. Using the technique, we establish a correlation between cell potential (Ecell) and cyclability of high-performance electrolytes for lithium metal anodes, where we find that solvents with more negative cell potentials and positive solvation energies-those weakly binding to Li+-lead to improved cycling stability. Cryogenic electron microscopy reveals that weaker solvation leads to an anion-derived solid-electrolyte interphase that stabilizes cycling. Using the potentiometric measurement for characterizing electrolytes, we establish a correlation that can guide the engineering of effective electrolytes for the lithium metal anode.

17.
BMC Microbiol ; 21(1): 29, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33468047

RESUMEN

BACKGROUND: Salmonella enterica remains a leading cause of food-borne diseases worldwide. Serotype information is important in food safety and public health activities to reduce the burden of salmonellosis. In the current study, two methods were used to determine serotypes of 111 strains of Salmonella isolated from poultry feces in Burkina Faso. First, Salmonella Multiplex Assay for Rapid Typing (SMART) Polymerase Chain Reaction (PCR) was used to determine the serovars of the S. enterica isolates. Second, serovar prediction based on whole genome sequencing (WGS) data was performed using SeqSero 2.0. RESULTS: Among the 111 Salmonella isolates, serotypes for 17 (15.31%) isolates were identified based on comparison to a panel of representative SMART codes previously determined for the 50 most common serovars in the United States. Forty-four (44) new SMART codes were developed for common and uncommon serotypes. A total of 105 (94.59%) isolates were serotyped using SeqSero 2.0 for serovar prediction based on WGS data. CONCLUSION: We determined that SeqSero 2.0 was more comprehensive for identifying Salmonella serotypes from Burkina Faso than SMART PCR.


Asunto(s)
Aves de Corral/microbiología , Salmonella/clasificación , Salmonella/genética , Serotipificación/métodos , Animales , Burkina Faso , Electroforesis Capilar , Heces/microbiología , Microbiología de Alimentos , Reacción en Cadena de la Polimerasa Multiplex , Filogenia , Salmonella/aislamiento & purificación , Secuenciación Completa del Genoma
18.
Analyst ; 146(8): 2449-2462, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33899053

RESUMEN

The COVID-19 pandemic has put the spotlight on the urgent need for integrated nucleic acid tests (NATs) for infectious diseases, especially those that can be used near patient ("point-of-care", POC), with rapid results and low cost, but without sacrificing sensitivity or specificity of gold standard PCR tests. In the US, the Clinical Laboratory Improvement Amendments Certificate of Waiver (CLIA-waiver) is mandated by the Food and Drug Administration (FDA) and designated to any laboratory testing with high simplicity and low risk for error, suitable for application in the POC. Since the first issuance of CLIA-waiver to Abbot's ID NOW Influenza A&B in 2015, many more NAT systems have been developed, received the CLIA-waiver in the US or World Health Organization (WHO)'s pre-qualification, and deployed to the front line of infectious disease detection. This review highlights the regulatory process for FDA and WHO in evaluating these NATs and the technology innovation of existing CLIA-waived systems. Understanding the technical advancement and challenges, unmet needs, and the trends of commercialization facilitated through the regulatory processes will help pave the foundation for future development and technology transfer from research to the market place.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Ácidos Nucleicos , Enfermedades Transmisibles/diagnóstico , Humanos , Ácidos Nucleicos/genética , Pandemias , Sistemas de Atención de Punto , Pruebas en el Punto de Atención , SARS-CoV-2
19.
Analyst ; 146(9): 2851-2861, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33949378

RESUMEN

The number of people living with HIV continues to increase with the current total near 38 million, of which about 26 million are receiving antiretroviral therapy (ART). These treatment regimens are highly effective when properly managed, requiring routine viral load monitoring to assess successful viral suppression. Efforts to expand access by decentralizing HIV nucleic acid testing in low- and middle-income countries (LMICs) has been hampered by the cost and complexity of current tests. Sample preparation of blood samples has traditionally relied on cumbersome RNA extraction methods, and it continues to be a key bottleneck for developing low-cost POC nucleic acid tests. We present a microfluidic paper-based analytical device (µPAD) for extracting RNA and detecting HIV in serum, leveraging low-cost materials, simple buffers, and an electric field. We detect HIV virions and MS2 bacteriophage internal control in human serum using a novel lysis and RNase inactivation method, paper-based isotachophoresis (ITP) for RNA extraction, and duplexed reverse transcription recombinase polymerase amplification (RT-RPA) for nucleic acid amplification. We design a specialized ITP system to extract and concentrate RNA, while excluding harsh reagents used for lysis and RNase inactivation. We found the ITP µPAD can extract and purify 5000 HIV RNA copies per mL of serum. We then demonstrate detection of HIV virions and MS2 bacteriophage in human serum within 45-minutes.


Asunto(s)
Infecciones por VIH , Isotacoforesis , Infecciones por VIH/diagnóstico , Humanos , Técnicas de Amplificación de Ácido Nucleico , ARN/genética , ARN Viral/genética , Recombinasas/genética , Recombinasas/metabolismo , Transcripción Reversa , Sensibilidad y Especificidad
20.
Arch Virol ; 166(5): 1485-1488, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33620554

RESUMEN

Fowlpox virus (FWPV), which is the type member of the genus Avipoxvirus, subfamily Chordopoxvirinae, family Poxviridae, can lead to significant losses to the poultry industry. Although a large number of fowlpox virus genomes have been sequenced and characterised globally, there are no sequences available at the genomic level from Australian isolates. Here, we present the first complete genome sequence of a fowlpox virus vaccine strain (FWPV-S) containing an integrated near-full-length reticuloendotheliosis virus (REV) provirus. The genome of FWPV-S showed the highest sequence similarity to a fowlpox virus from the USA (97.74% identity). The FWPV-S genome contained 16 predicted unique genes, while a further two genes were fragmented compared to previously reported FWPV genome sequences. Subsequent phylogenetic analysis showed that FWPV-S was most closely related to other fowlpox viruses. This is the first reported genome sequence of FWPV from Australia.


Asunto(s)
Virus de la Viruela de las Aves de Corral/genética , Provirus/genética , Virus de la Reticuloendoteliosis/genética , Vacunas Virales/genética , Animales , Australia , Secuencia de Bases , Células Cultivadas , Embrión de Pollo , ADN Viral/genética , Virus de la Viruela de las Aves de Corral/clasificación , Virus de la Viruela de las Aves de Corral/aislamiento & purificación , Genes Virales , Genoma Viral/genética , Sistemas de Lectura Abierta , Filogenia , Vacunas Virales/clasificación , Vacunas Virales/aislamiento & purificación , Integración Viral
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA