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2.
Inorg Chem ; 63(14): 6383-6395, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38513066

RESUMO

A three-dimensional (3D) Ni-MOF of the formula [Ni(C4H4N2)(CHO2)2]n, has been reported, which shows a capacitance of 2150 F/g at a current density of 1A/g in a three-electrode setup (5.0 M KOH). Post-mortem analysis of the sample after three-electrode measurements revealed the bias-induced transformation of Ni-MOF to Ni(OH)2, which has organic constituents intercalated within the sample exhibiting better storage performance than bulk Ni(OH)2. Afterward, the synthesized MOF and reduced graphene (rGO) were used as the anode and cathode electrode material, respectively, and a two-electrode asymmetric supercapacitor device (ASC) setup was designed that exhibited a capacitance of 125 F/g (at 0.2 A/g) with a high energy density of 50.17 Wh/kg at a power density of 335.1 W/kg. The ASC further has a very high reversibility (97.9% Coulombic efficiency) and cyclic stability (94%) after 5000 constant charge-discharge cycles. Its applicability was also demonstrated by running a digital watch. Using sophisticated density functional theory simulations, the electronic properties, diffusion energy barrier for the electrolytic ions (K+), and quantum capacitance for the Ni(OH)2 electrode have been reported. The lower diffusion energy barrier (0.275 eV) and higher quantum capacitance (1150 µF/cm2) are attributed to the higher charge storage performance of the Ni-MOF-transformed Ni(OH)2 electrode as observed in the experiment.

3.
J Clin Virol ; 174: 105705, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39002309

RESUMO

BACKGROUND: Epstein-Barr Virus (EBV) is associated with lung disease in immunocompromised patients, particularly transplant recipients. EBV DNA testing of lower respiratory tract specimens may have diagnostic utility. METHODS: This was a retrospective, observational study of all patients with bronchoalveolar lavage (BAL) fluids submitted for EBV qPCR testing from February 2016 to June 2022 at the Stanford Clinical Virology Laboratory. RESULTS: There were 140 patients that underwent 251 EBV qPCR BAL tests (median 1; range 1 - 10). These patients had a mean age of 15.9 years (standard deviation, 15.1 years) and 50 % were female. Transplant recipients accounted for 67.1 % (94/140) of patients, including 67.0 % (63/94) solid organ transplant (SOT) and 33.0 % (31/94) hematopoietic cell transplant. Diagnostic testing was performed more commonly than surveillance testing [57.0 % (143/251) v. 43.0 % (108/251)]; 96.2 % (104/108) of surveillance samples were from lung transplant recipients. Excluding internal control failures, 34.7 % (83/239) of BAL had detectable EBV DNA, encompassing a wide range of viral loads (median=3.03 log10 IU/mL, range 1.44 to 6.06). Overall agreement of EBV DNA in BAL compared to plasma was 74.1 % [117/158; 95 % confidence interval (CI): 66.5 % to 80.7 %], with a kappa coefficient of 0.44 (95 % CI: 0.30 to 0.57). Only 20.1 % (48/239) of results were discussed in a subsequent clinical note, and one result (0.4 %; 1/239) changed clinical management. CONCLUSIONS: EBV qPCR testing on BAL offers limited clinical impact. Additional biomarkers are required to improve the diagnosis of EBV-associated lung diseases.

4.
mSphere ; 9(7): e0022424, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38926903

RESUMO

Respiratory syncytial virus (RSV) causes a large burden of respiratory illness globally. It has two subtypes, RSV A and RSV B, but little is known regarding the predominance of these subtypes during different seasons and their impact on morbidity and mortality. Using molecular methods, we quantified RSV A and RSV B RNA in wastewater solids across multiple seasons and metropolitan areas to gain insight into the predominance of RSV subtypes. We determined the predominant subtype for each group using the proportion of RSV A to total RSV (RSV A + RSV B) in each wastewater sample (PA,WW) and conducted a comparative analysis temporally, spatially, and against clinical specimens. A median PA,WW of 0.00 in the first season and 0.58 in the second season indicated a temporal shift in the predominant subtype. Spatially, while we observed dominance of the same subtype, PA,WW was higher in some areas (PA,WW = 0.58-0.88). The same subtype predominated in wastewater and clinical samples, but clinical samples showed higher levels of RSV A (RSV A positivity in clinical samples = 0.79, median PA,WW = 0.58). These results suggest that wastewater, alongside clinical data, holds promise for enhanced subtype surveillance.IMPORTANCERespiratory syncytial virus (RSV) causes a large burden of respiratory illness globally. It has two subtypes, RSV A and RSV B, but little is known regarding the predominance of these subtypes during different seasons and their impact on morbidity and mortality. The study illustrates that information on subtype predominance can be gleaned from wastewater. As a biological composite sample from the entire contributing population, wastewater monitoring of RSV A and B can complement clinical surveillance of RSV.


Assuntos
RNA Viral , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Estações do Ano , Águas Residuárias , Águas Residuárias/virologia , Humanos , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/classificação , Vírus Sincicial Respiratório Humano/isolamento & purificação , Infecções por Vírus Respiratório Sincicial/virologia , RNA Viral/genética , Análise Espaço-Temporal
6.
Microbiol Spectr ; 12(4): e0390823, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38466093

RESUMO

Despite having high analytical sensitivities and specificities, qualitative SARS-CoV-2 nucleic acid amplification tests (NAATs) cannot distinguish infectious from non-infectious virus in clinical samples. In this study, we determined the highest cycle threshold (Ct) value of the SARS-CoV-2 targets in the Xpert Xpress SARS-CoV-2/Flu/RSV (Xpert 4plex) test that corresponded to the presence of detectable infectious SARS-CoV-2 in anterior nasal swab samples. A total of 111 individuals with nasopharyngeal swab specimens that were initially tested by the Xpert Xpress SARS-CoV-2 test were enrolled. A healthcare worker subsequently collected anterior nasal swabs from all SARS-CoV-2-positive individuals, and those specimens were tested by the Xpert 4plex test, viral culture, and laboratory-developed assays for SARS-CoV-2 replication intermediates. SARS-CoV-2 Ct values from the Xpert 4plex test were correlated with data from culture and replication intermediate testing to determine the Xpert 4plex assay Ct value that corresponded to the presence of infectious virus. Ninety-eight of the 111 (88.3%) individuals initially tested positive by the Xpert Xpress SARS-CoV-2 test. An anterior nasal swab specimen collected from positive individuals a median of 2 days later (range, 0-9 days) tested positive for SARS-CoV-2 by the Xpert 4plex test in 39.8% (39/98) of cases. Of these samples, 13 (33.3%) were considered to contain infectious virus based on the presence of cultivable virus and replication intermediates, and the highest Ct value observed for the Xpert 4plex test in these instances was 26.3. Specimens that yielded Ct values of ≤26.3 when tested by the Xpert 4plex test had a likelihood of containing infectious SARS-CoV-2; however, no infectious virus was detected in specimens with higher Ct values.IMPORTANCEUnderstanding the correlation between real-time PCR test results and the presence of infectious SARS-CoV-2 may be useful for informing patient management and workforce return-to-work or -duty. Further studies in different patient populations are needed to correlate Ct values or other biomarkers of viral replication along with the presence of infectious virus in clinical samples.


Assuntos
COVID-19 , Doenças Transmissíveis , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Nasofaringe , Técnicas de Diagnóstico Molecular/métodos , Teste para COVID-19
7.
bioRxiv ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38659941

RESUMO

In search for broad-spectrum antivirals, we discovered a small molecule inhibitor, RMC-113, that potently suppresses the replication of multiple RNA viruses including SARS-CoV-2 in human lung organoids. We demonstrated selective dual inhibition of the lipid kinases PIP4K2C and PIKfyve by RMC-113 and target engagement by its clickable analog. Advanced lipidomics revealed alteration of SARS-CoV-2-induced phosphoinositide signature by RMC-113 and linked its antiviral effect with functional PIP4K2C and PIKfyve inhibition. We discovered PIP4K2C's roles in SARS-CoV-2 entry, RNA replication, and assembly/egress, validating it as a druggable antiviral target. Integrating proteomics, single-cell transcriptomics, and functional assays revealed that PIP4K2C binds SARS-CoV-2 nonstructural protein 6 and regulates virus-induced impairment of autophagic flux. Reversing this autophagic flux impairment is a mechanism of antiviral action of RMC-113. These findings reveal virus-induced autophagy regulation via PIP4K2C, an understudied kinase, and propose dual inhibition of PIP4K2C and PIKfyve as a candidate strategy to combat emerging viruses.

8.
bioRxiv ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38370837

RESUMO

The rapid emergence of divergent SARS-CoV-2 variants has led to an update of the COVID-19 booster vaccine to a monovalent version containing the XBB.1.5 spike. To determine the neutralization breadth following booster immunization, we collected blood samples from 24 individuals pre- and post-XBB.1.5 mRNA booster vaccination (∼1 month). The XBB.1.5 booster improved both neutralizing activity against the ancestral SARS-CoV-2 strain (WA1) and the circulating Omicron variants, including EG.5.1, HK.3, HV.1, XBB.1.5 and JN.1. Relative to the pre-boost titers, the XBB.1.5 monovalent booster induced greater total IgG and IgG subclass binding, particular IgG4, to the XBB.1.5 spike as compared to the WA1 spike. We evaluated antigen-specific memory B cells (MBCs) using either spike or receptor binding domain (RBD) probes and found that the monovalent booster largely increases non-RBD cross-reactive MBCs. These data suggest that the XBB.1.5 monovalent booster induces cross-reactive antibodies that neutralize XBB.1.5 and related Omicron variants.

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