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1.
Inorg Chem ; 63(14): 6383-6395, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38513066

ABSTRACT

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.

2.
Microbiol Spectr ; 12(4): e0390823, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38466093

ABSTRACT

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.


Subject(s)
COVID-19 , Communicable Diseases , Humans , SARS-CoV-2/genetics , COVID-19/diagnosis , Nasopharynx , Molecular Diagnostic Techniques/methods , COVID-19 Testing
3.
bioRxiv ; 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38370837

ABSTRACT

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.

4.
J Clin Virol ; 168: 105582, 2023 11.
Article in English | MEDLINE | ID: mdl-37788527

ABSTRACT

BACKGROUND: Cytomegalovirus (CMV) causes significant morbidity and mortality in immunocompromised patients, particularly transplant recipients. Quantitation of CMV DNA in peripheral blood is used to monitor prophylactic and pre-emptive approaches to prevent CMV disease, whereas CMV DNA testing of non-plasma specimens may aid in the diagnosis of end-organ disease. METHODS: The analytical performance of the FDA-approved Aptima CMV Quant Assay was evaluated using reference CMV (SeraCare) diluted in defibrinated human plasma, as well as negative bronchoalveolar lavage fluid and tissue. Agreement was determined using 100 clinical acid-citrate-dextrose (ACD) plasma specimens, 77 bronchoalveolar lavage (BAL) fluids, and 101 tissues previously tested using artus CMV qPCR. RESULTS: Aptima CMV lower limit of detection (LLOD) was 169 IU/mL for ACD plasma, 100 IU/mL for BAL, and 50 IU/mL for tissue. Positive percent agreement (PPA) was 100.0% (50/50; 95% CI: 92.9% - 100.0%) and negative percent agreement (NPA) was 94.0% (47/50; 95% CI: 83.5% - 98.8%) for ACD plasma. Bland-Altman analysis revealed a bias of 0.20 log10 IU/mL (Aptima - artus) with 95% limits of agreement of -0.53 to 0.93. For BAL fluids, PPA was 70.0% (14/20; 95% CI: 45.7% - 88.1%) and NPA was 82.4% (43/51; 95% CI: 69.1% - 91.6%). For tissues, PPA was 90.0% (45/50; 95% CI: 78.2% - 96.7%) and NPA was 94.0% (47/50; 95% CI: 83.5% - 98.8%). CONCLUSIONS: The Aptima CMV Quant Assay demonstrates high analytical sensitivity and good overall agreement using clinical plasma and tissue specimens.


Subject(s)
Cytomegalovirus Infections , Cytomegalovirus , Humans , Cytomegalovirus/genetics , Bronchoalveolar Lavage , Cytomegalovirus Infections/diagnosis , Bronchoalveolar Lavage Fluid , Nucleic Acid Amplification Techniques , Viral Load , DNA , DNA, Viral/genetics
5.
J Gen Virol ; 104(10)2023 10.
Article in English | MEDLINE | ID: mdl-37801004

ABSTRACT

Human immunodeficiency virus 1 (HIV-1) reverse transcriptase (RT) initiation depends on interaction between viral 5'-leader RNA, RT and host tRNA3Lys. Therefore, we sought to identify co-evolutionary changes between the 5'-leader and RT in viruses developing RT-inhibitor resistance mutations. We sequenced 5'-leader positions 37-356 of paired plasma virus samples from 29 individuals developing the nucleoside RT inhibitor (NRTI)-resistance mutation M184V, 19 developing a non-nucleoside RT inhibitor (NNRTI)-resistance mutation and 32 untreated controls. 5'-Leader variants were defined as positions where ≥20 % of next-generation sequencing (NGS) reads differed from the HXB2 sequence. Emergent mutations were defined as nucleotides undergoing a ≥4-fold change in proportion between baseline and follow-up. Mixtures were defined as positions containing ≥2 nucleotides each present in ≥20 % of NGS reads. Among 80 baseline sequences, 87 positions (27.2 %) contained a variant; 52 contained a mixture. Position 201 was the only position more likely to develop a mutation in the M184V (9/29 vs 0/32; P=0.0006) or NNRTI-resistance (4/19 vs 0/32; P=0.02; Fisher's exact test) groups than the control group. Mixtures at positions 200 and 201 occurred in 45.0 and 28.8 %, respectively, of baseline samples. Because of the high proportion of mixtures at these positions, we analysed 5'-leader mixture frequencies in two additional datasets: five publications reporting 294 dideoxyterminator clonal GenBank sequences from 42 individuals and six National Center for Biotechnology Information (NCBI) BioProjects reporting NGS datasets from 295 individuals. These analyses demonstrated position 200 and 201 mixtures at proportions similar to those in our samples and at frequencies several times higher than at all other 5'-leader positions. Although we did not convincingly document co-evolutionary changes between RT and 5'-leader sequences, we identified a novel phenomenon, wherein positions 200 and 201 immediately downstream of the HIV-1 primer binding site exhibited an extraordinarily high likelihood of containing a nucleotide mixture. Possible explanations for the high mixture rates are that these positions are particularly error-prone or provide a viral fitness advantage.


Subject(s)
Anti-HIV Agents , HIV Infections , HIV-1 , Humans , Reverse Transcriptase Inhibitors/pharmacology , Reverse Transcriptase Inhibitors/therapeutic use , HIV-1/genetics , Mutation , HIV Reverse Transcriptase/genetics , HIV Reverse Transcriptase/chemistry , HIV Reverse Transcriptase/metabolism , Nucleotides/therapeutic use , Anti-HIV Agents/pharmacology , Drug Resistance, Viral/genetics
6.
IDCases ; 33: e01881, 2023.
Article in English | MEDLINE | ID: mdl-37680215

ABSTRACT

As part of an epidemiologic survey, we screened remnant samples collected for STI testing for mpox virus. We identified two cases of presumed MPXV infection in pregnant, heterosexual cisgender women. Here, we describe their pregnancy and birth outcomes. Both patients required induction of labor and experienced labor complicated by chorioamnionitis.

7.
Pract Lab Med ; 36: e00329, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37649537

ABSTRACT

Background: Quantitation of human herpesvirus-6 (HHV-6) DNA in clinical specimens is important for the diagnosis and management of HHV-6-associated infection and reactivation in immunocompromised patients, particularly transplant recipients. Methods: The analytical performance of the Altona RealStar ASR HHV-6 qPCR on the semi-automated AltoStar AM16 system was assessed using HHV-6 reference material in plasma and cerebral spinal fluid (CSF). Qualitative and quantitative agreement was determined using 123 clinical EDTA plasma specimens tested using a laboratory-developed HHV-6 qPCR. Results: The 95% Lower Limit of Detection was 20 IU/mL [95% confidence interval (CI): 10 to 29] in plasma and 78 IU/mL (95% CI: 55 to 146) in CSF. The assay was linear from 7.0 to 2.0 log10 IU/mL in both matrices. Overall agreement of the RealStar ASR HHV-6 qPCR on the AltoStar AM16 with a laboratory-developed test was 95.9% (95% CI: 90.8 to 98.7). Passing-Bablok analysis of specimens quantifiable by both methods and at levels >1000 copies/mL revealed a regression line of Y = 1.00*X-0.20, with neither systematic (95% CI Y-intercept: -0.66 to 0.26) nor proportional (95% CI slope: 0.89 to 1.10) bias compared to the reference. Conclusions: The RealStar ASR HHV-6 qPCR on the AltoStar AM16 provides accurate quantitation for clinical monitoring of HHV-6 in immunocompromised hosts.

8.
Dalton Trans ; 52(31): 10876-10884, 2023 Aug 08.
Article in English | MEDLINE | ID: mdl-37486294

ABSTRACT

Amine-templated 1D cobalt fluoro sulfate of the composition [(CH3)2NH2]2[Co4F4(SO4)3(C3N2H4)4], consisting of Co4F4 cubane-type secondary building unit, has been synthesized under solvothermal condition. The magnetic properties of the Co4F4 cubane chain exhibited a low-temperature magnetic ordering below 17 K (Tc) attributed to intra-cluster ferromagnetic coupling and did not show spin-glass freezing. The selenylation of the Co4F4 cubane chain leads to the formation of sphere-like CoSe2 in the hydrothermal route (CoSe2@HT). At the same time, nanorods of CoSe2 encapsulated with carbon matrix were obtained in a sealed tube method (CoSe2@ST). Moreover, CoSe2@ST exhibited a higher hydrogen evolution reaction (HER) activity than CoSe2@HT in an acidic medium with 177 mV overpotential to achieve the benchmark current density of 10 mA cm-2. The promising HER performance of derived CoSe2@ST could be attributed to an increase in the geometrical and specific activity due to the encapsulation of N-doped carbon matrix over the CoSe2 nanorods that facilitate faster charge transfer at the electrode-electrolyte interface and higher electrochemical conductivity than the derived CoSe2@HT. This work demonstrates a low-temperature, solvent- and reducing agent-free new synthetic approach for synthesizing framework-derived materials.

9.
Nat Commun ; 14(1): 4486, 2023 07 26.
Article in English | MEDLINE | ID: mdl-37495593

ABSTRACT

Genetic analysis methods are foundational to advancing personalized medicine, accelerating disease diagnostics, and monitoring the health of organisms and ecosystems. Current nucleic acid technologies such as polymerase chain reaction (PCR) and next-generation sequencing (NGS) rely on sample amplification and can suffer from inhibition. Here, we introduce a label-free genetic screening platform based on high quality (high-Q) factor silicon nanoantennas functionalized with nucleic acid fragments. Each high-Q nanoantenna exhibits average resonant quality factors of 2,200 in physiological buffer. We quantitatively detect two gene fragments, SARS-CoV-2 envelope (E) and open reading frame 1b (ORF1b), with high-specificity via DNA hybridization. We also demonstrate femtomolar sensitivity in buffer and nanomolar sensitivity in spiked nasopharyngeal eluates within 5 minutes. Nanoantennas are patterned at densities of 160,000 devices per cm2, enabling future work on highly-multiplexed detection. Combined with advances in complex sample processing, our work provides a foundation for rapid, compact, and amplification-free molecular assays.


Subject(s)
COVID-19 , Nucleic Acids , Humans , SARS-CoV-2/genetics , COVID-19/diagnosis , COVID-19/genetics , Ecosystem , Genetic Testing , Sensitivity and Specificity , Nucleic Acid Amplification Techniques/methods
10.
medRxiv ; 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37333388

ABSTRACT

Background: HIV-1 RT initiation depends on interaction between viral 5'-leader RNA, RT, and host tRNA3Lys. We therefore sought to identify co-evolutionary changes between the 5'-leader and RT in viruses developing RT-inhibitor resistance mutations. Methods: We sequenced 5'-leader positions 37-356 of paired plasma virus samples from 29 individuals developing the NRTI-resistance mutation M184V, 19 developing an NNRTI-resistance mutation, and 32 untreated controls. 5'-leader variants were defined as positions where ≥20% of NGS reads differed from the HXB2 sequence. Emergent mutations were defined as nucleotides undergoing ≥4-fold change in proportion between baseline and follow-up. Mixtures were defined as positions containing ≥2 nucleotides each present in ≥20% of NGS reads. Results: Among 80 baseline sequences, 87 positions (27.2%) contained a variant; 52 contained a mixture. Position 201 was the only position more likely to develop a mutation in the M184V (9/29 vs. 0/32; p=0.0006) or NNRTI-resistance (4/19 vs. 0/32; p=0.02; Fisher's Exact Test) groups than the control group. Mixtures at positions 200 and 201 occurred in 45.0% and 28.8%, respectively, of baseline samples. Because of the high proportion of mixtures at these positions, we analyzed 5'-leader mixture frequencies in two additional datasets: five publications reporting 294 dideoxyterminator clonal GenBank sequences from 42 individuals and six NCBI BioProjects reporting NGS datasets from 295 individuals. These analyses demonstrated position 200 and 201 mixtures at proportions similar to those in our samples and at frequencies several times higher than at all other 5'-leader positions. Conclusions: Although we did not convincingly document co-evolutionary changes between RT and 5'-leader sequences, we identified a novel phenomenon, wherein positions 200 and 201, immediately downstream of the HIV-1 primer binding site exhibited an extraordinarily high likelihood of containing a nucleotide mixture. Possible explanations for the high mixture rates are that these positions are particularly error-prone or provide a viral fitness advantage.

11.
Vox Sang ; 118(8): 674-680, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37366233

ABSTRACT

BACKGROUND AND OBJECTIVES: Hepatitis E virus (HEV) is an underrecognized and emerging infectious disease that may threaten the safety of donor blood supply in many parts of the world. We sought to elucidate whether our local community blood supply is at increased susceptibility for transmission of transfusion-associated HEV infections. MATERIALS AND METHODS: We screened 10,002 randomly selected donations over an 8-month period between 2017 and 2018 at the Stanford Blood Center for markers of HEV infection using commercial IgM/IgG serological tests and reverse transcriptase quantitative polymerase chain reaction assays (RT-qPCR). Donor demographic information, including gender, age, self-identified ethnicity, location of residence and recent travel, were obtained from the donor database and used to generate multivariate binary logistic regressions for risk factors of IgG seropositivity. RESULTS: A total of 10,002 blood donations from 7507 unique donors were screened, and there was no detectable HEV RNA by RT-qPCR. The overall seropositivity rate was 12.1% for IgG and 0.56% for IgM. Multivariate analysis of unique donors revealed a significantly higher risk of IgG seropositivity with increasing age, White/Asian ethnicities and residence in certain local counties. CONCLUSION: Although HEV IgG seroprevalence in the San Francisco Bay Area is consistent with ongoing infection, the screening of a large donor population did not identify any viraemic blood donors. While HEV is an underrecognized and emerging infection in other regions, there is no evidence to support routine blood screening for HEV in our local blood supply currently; however, periodic monitoring may still be required to assess the ongoing risk.


Subject(s)
Hepatitis E virus , Hepatitis E , Humans , Blood Donors , Hepatitis Antibodies , Hepatitis E/epidemiology , Hepatitis E virus/genetics , Immunoglobulin G , Immunoglobulin M , RNA, Viral , Seroepidemiologic Studies , Male , Female
12.
Soft Matter ; 19(19): 3510-3518, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37145490

ABSTRACT

The present study has been undertaken with an aim to design and develop safer and more efficient all solid-state electrolytes, so that the issues associated with the use of conventional room temperature ionic liquid-based electrolytes can be tackled. To fulfil this objective, a series of geminal di-cationic Organic Ionic Crystals (OICs), based on C3-, C6-, C8- and C9-alkylbridged bis-(methylpyrrolidinium)bromide are synthesized, and the structural features, thermal properties and phase behaviours of these as synthesized OICs have been investigated. Additionally, a number of electro-analytical techniques have been employed to assess their suitability as an efficient electrolyte composite (OIC:I2:TBAI) for all solid-state dye sensitised solar cells (DSSCs). The structural analysis has revealed that along with excellent thermal stability and well-defined surface morphology, all thsese OICs exhibit a well-ordered three-dimensional network of cations and anions that can serve as a conducting channel for the diffusion of iodide ions. Electrochemical investigations have shown that OICs with an intermediate length of alkyl bridge (C6- and C8-alkyl bridged) show better electrolytic performance than those that are based on OICs with a relatively shorter (C3-) or longer (C9-) alkyl-bridge chain. A careful analysis of the above data has essentially demonstrated that the length of the alkyl bridge chain plays a significant role in determining the structural organisation, morphology and eventually the ionic conductivity of OICs. Overall, the comprehensive knowledge on OICs that has been extracted from the current study is expected to be helpful to explore further new types of OIC-based all solid-state electrolytes with improved electrolytic performance for targeted applications.

13.
J Clin Virol ; 164: 105493, 2023 07.
Article in English | MEDLINE | ID: mdl-37220710

ABSTRACT

BACKGROUND: Despite the sharp increase in mpox (formerly monkeypox) incidence and the wide geographic spread of mpox during the 2022 outbreak, the community prevalence of infection remains poorly characterized. This study is a retrospective epidemiologic survey to estimate mpox prevalence. METHODS: Samples obtained for sexually transmitted infection (STI) testing from April to September 2022 in the public hospital and clinic system of San Mateo County, California were screened for mpox virus (MPXV) using polymerase chain reaction. RESULTS: 16/1,848 samples from 11/1,645 individuals were positive for MPXV by qPCR. 4/11 individuals with positive MPXV testing were cisgender women, 2 of whom were pregnant at the time of sample collection. Both deliveries were complicated by chorioamnionitis. Anorectal and oropharyngeal samples were the most likely to be positive for MPXV (4/60 anorectal samples and 4/66 oropharyngeal samples compared with 5/1,264 urine samples and 3/445 vaginal samples). CONCLUSIONS: Our study is one of the first epidemiologic surveys for MPXV infection outside of sexual health/STI clinic settings. Relatively high rates of MPXV from oropharyngeal and anorectal samples reinforces the importance of MPXV testing at various anatomic sites, particularly if patients are presenting with non-lesional symptoms (pharyngitis, proctitis). However, the United States Food and Drug Administration (FDA) has not yet authorized non-lesional MPXV testing. The identification of MPXV in women in our cohort suggests that the rates of mpox in women may have previously been underestimated and highlights the risk of pregnancy complications associated with mpox.


Subject(s)
Pregnancy , Humans , Female , Prevalence , Retrospective Studies , Ambulatory Care Facilities , California/epidemiology , Monkeypox virus
14.
J Clin Virol ; 164: 105468, 2023 07.
Article in English | MEDLINE | ID: mdl-37119583

ABSTRACT

BACKGROUND: Tests that sensitively detect the presence of actively replicating SARS-CoV-2 may improve patient care by allowing the safe and timely discontinuation of isolation. Correlates of active replication include nucleocapsid antigen and virus minus-strand RNA. METHODS: Qualitative agreement of the DiaSorin LIAISON SARS-CoV-2 nucleocapsid antigen chemiluminescent immunoassay (CLIA) with minus-strand RNA was determined using 402 upper respiratory specimens from 323 patients previously tested using a laboratory-developed SARS-CoV-2 strand-specific RT-qPCR. Nucleocapsid antigen levels, minus-strand and plus-strand cycle threshold values, as well as virus culture, were used to evaluate discordant specimens. Receiver operating characteristic curves were also used to identify virus RNA thresholds for active replication, including values harmonized to the World Health Organization International Standard. RESULTS: Overall agreement was 92.0% [95% confidence interval (CI): 89.0 - 94.5], positive percent agreement was 90.6% (95% CI: 84.4 - 95.0), and negative percent agreement was 92.8% (95% CI: 89.0 - 95.6). The kappa coefficient was 0.83 (95% CI: 0.77 - 0.88). Discordant specimens contained low levels of nucleocapsid antigen and minus-strand RNA. 84.8% (28/33) were negative by culture. Sensitivity-optimized plus-strand RNA thresholds for active replication were 31.6 cycles or 3.64 log10 IU/mL; resulting in 100.0% sensitivity (95% CI: 97.6 to 100.0) and 55.9 specificity (95% CI: 49.7 to 62.0). CONCLUSIONS: Detection of nucleocapsid antigen by CLIA performs equivalently to minus-strand detection via strand-specific RT-qPCR, though these methods may overestimate replication-competent virus compared to culture. Careful implementation of biomarkers for actively replicating SARS-CoV-2 has the potential to inform infection control decision-making and patient management.


Subject(s)
COVID-19 , Humans , COVID-19/diagnosis , SARS-CoV-2/genetics , Nucleocapsid , Polymerase Chain Reaction , RNA, Viral/genetics , Sensitivity and Specificity , COVID-19 Testing
15.
J Clin Virol ; 162: 105444, 2023 05.
Article in English | MEDLINE | ID: mdl-37043903

ABSTRACT

BACKGROUND: SARS-CoV-2 variant surveillance informs vaccine composition and decisions to de-authorize antibody therapies. Though detailed genetic characterization requires whole-genome sequencing, targeted mutation analysis may complement pandemic surveillance efforts. METHODS: This study investigated the qualitative performance of a multiplex oligonucleotide ligation assay targeting 19 spike mutations using 192 whole genome sequenced upper respiratory samples representing SARS-CoV-2 variants of concern. RESULTS: Initial valid results were obtained from 95.8% [95% confidence interval (CI): 92.0 - 98.2; 184/192] of samples. All eight invalid samples were valid on repeat testing. When comparing SARS-CoV-2 oligonucleotide ligase assay SARS-CoV-2 variant calls with whole genome sequencing, overall positive percent agreement was 100% (95% CI: 98.1 - 100.0; 192/192), as was the positive and negative percent agreement for each of the tested variants; Gamma, Delta, Omicron BA.1, BA.2, and BA.4/BA.5. CONCLUSIONS: This multiplexed oligonucleotide ligation assays demonstrated accurate SARS-CoV-2 variant typing compared to whole genome sequencing. Such an approach has the potential to provide improved turnaround compared to sequencing and more detailed mutation coverage than RT-qPCR.


Subject(s)
COVID-19 , Humans , COVID-19/diagnosis , SARS-CoV-2/genetics , Biological Assay , Mutation , Oligonucleotides
16.
J Mol Diagn ; 25(7): 490-501, 2023 07.
Article in English | MEDLINE | ID: mdl-37068736

ABSTRACT

Plasma Epstein-Barr virus (EBV) DNA is an established biomarker for endemic nasopharyngeal carcinoma. However, existing real-time quantitative PCR (qPCR) assays are limited by poor interlaboratory reproducibility. This is a barrier to biomarker integration into staging systems and management. It was hypothesized that EBV digital PCR (dPCR) would have similar sensitivity but improved precision relative to qPCR. Using the World Health Organization EBV standard and patient specimens, the NRG-HN001 BamHI-W qPCR, two commercial EBNA-1 qPCR assays, and two laboratory-developed dPCR assays amplifying the BamHI-W, EBNA-1, and EBER targets were compared. Testing was conducted in the North American reference laboratory for the NRG-HN001 randomized trial. The EBV dPCR assays achieved similar performance compared with qPCR. Although dPCR does not require quantitation standards, different dPCR thresholding algorithms yielded significant qualitative and quantitative variation. This was most evident with low levels of EBV DNA. No-template control-informed thresholding (ddpcRquant) mitigated false-positive/false-negative findings. The NRG-HN001 BamHI-W qPCR and laboratory-developed BamHI-W droplet dPCR offered higher sensitivity, lower limit of blank, higher precision at low plasma EBV DNA levels (≤1500 IU/mL), and higher overall agreement with clinical specimens versus single-copy qPCR/dPCR targets (EBNA-1/EBER). These data confirm the rationale for using the BamHI-W target to define prognostic thresholds and indicate that both qPCR and dPCR methods harmonized to the World Health Organization standard can provide the necessary analytical performance.


Subject(s)
Epstein-Barr Virus Infections , Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/diagnosis , Nasopharyngeal Carcinoma/genetics , Herpesvirus 4, Human/genetics , Real-Time Polymerase Chain Reaction/methods , Epstein-Barr Virus Infections/diagnosis , Reproducibility of Results , DNA, Viral/analysis , Biomarkers , Nasopharyngeal Neoplasms/diagnosis , Nasopharyngeal Neoplasms/genetics
17.
Emerg Infect Dis ; 29(4): 848-850, 2023 04.
Article in English | MEDLINE | ID: mdl-36918374

ABSTRACT

We retrospectively screened oropharyngeal and rectal swab samples originally collected in California, USA, for Chlamydia trachomatis and Neisseria gonorrhoeae testing for the presence of monkeypox virus DNA. Among 206 patients screened, 17 (8%) had samples with detectable viral DNA. Monkeypox virus testing from mucosal sites should be considered for at-risk patients.


Subject(s)
Chlamydia Infections , Gonorrhea , Humans , California/epidemiology , Chlamydia Infections/diagnosis , Chlamydia Infections/epidemiology , Chlamydia trachomatis/genetics , Chlamydia trachomatis/isolation & purification , DNA , Gonorrhea/diagnosis , Monkeypox virus/genetics , Monkeypox virus/isolation & purification , Neisseria gonorrhoeae/genetics , Neisseria gonorrhoeae/isolation & purification , Retrospective Studies , /diagnosis
18.
Microbiol Spectr ; : e0501022, 2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36847504

ABSTRACT

Human adenoviruses (HAdVs) cause severe disease in immunocompromised patients. Quantitation of HAdV DNA in peripheral blood is used to assess the risk of disseminated disease and to monitor response to therapy. The lower limit of detection, precision, and linearity of the semiautomated AltoStar adenovirus quantitative PCR (qPCR) was evaluated using reference HAdV-E4 in EDTA plasma and respiratory virus matrix. Qualitative and quantitative agreement was determined using 122 clinical EDTA plasma specimens previously tested using a laboratory-developed HAdV qPCR. The 95% lower limit of detection (LLOD) was 33 IU/mL (95% confidence interval [CI], 10 to 56) for EDTA plasma and 188 IU/mL (95% CI, 145 to 304) for respiratory swab matrix. In both matrices, the AltoStar HAdV qPCR was linear from 7.0 to 2.0 log10 IU/mL. For the clinical specimens, overall agreement was 96.7% (95% CI, 91.8 to 99.1), positive percent agreement was 95.5% (95% CI, 87.6 to 98.5), and negative percent agreement was 98.2% (95% CI, 88.5 to 99.7). Passing-Bablok analysis of specimens quantifiable by both methods revealed a regression line of Y = 1.11 · X + 0.00; there was positive proportional bias (95% CI of the slope, 1.05 to 1.22) but no systematic bias (95% CI of the Y-intercept, -0.43 to 0.23) compared to the reference. The AltoStar platform provides accurate quantitation of HAdV DNA and provides a semiautomated option for the clinical monitoring of HAdV following transplantation. IMPORTANCE Accurate quantification of human adenovirus DNA in the peripheral blood plays a critical role in the management of adenovirus infections in transplant recipients. Many laboratories utilize in-house laboratory-based PCR assays for the quantification of human adenovirus, as there are few commercial options available. Here, we describe the analytical and clinical performance of the semiautomated AltoStar adenovirus quantitative PCR (Altona Diagnostics). This platform provides sensitive, precise, and accurate quantification of adenovirus DNA that is well suited for virological testing following transplantation. Prior to implementing a new quantitative test in the clinical laboratory, a rigorous evaluation is required to determine assay performance characteristics and to correlate results to current in-house methods of quantitation.

19.
ACS Omega ; 7(44): 39985-39997, 2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36385820

ABSTRACT

The self-assembly of a carboxylate-based dinucleating ligand, N,N'-bis[2-carboxybenzomethyl]-N,N'-bis[2-pyridylmethyl]-1,3-diaminopropan-2-ol (H3cpdp), and copper(II) ions in the presence of various exogenous ancillary ligands results in the formation of the new dinuclear complex [Cu2(cpdp)(µ-Hisophth)]4·2H2isophth·21H2O (1), trinuclear complex [Cu3(Hcpdp)(Cl)4] (2), and tetranuclear complex [Cu4(cpdp)(µ-Hphth)(µ4-phth)(piconol)(Cl)2]·3H2O (3) (H2phth = phthalic acid; H2isophth = isophthalic acid; piconol = 2-pyridinemethanol; Cl- = chloride). In methanol-water, the reaction of H3cpdp with CuCl2·2H2O at room temperature leads to the formation of 2. On the other hand, 1 and 3 have been obtained by carrying out the reaction of H3cpdp with CuCl2·2H2O/m-C6H4(CO2Na)2 and CuCl2·2H2O/o-C6H4(CO2Na)2/piconol, respectively, in methanol-water in the presence of NaOH at ambient temperature. All three complexes have been characterized by elemental analysis, molar electrical conductivity and magnetic moment measurements, FTIR, UV-vis spectroscopy, and PXRD, including single-crystal X-ray structural analyses. The molecular structure of 1 is based on a µ-alkoxide and µ-isophthalate-bridged dimeric [Cu2] core; the structure of 2 represents a trimeric [Cu3] core in which a µ-alcohol-bridged dinuclear [Cu2] unit is exclusively coupled with a [CuCl2] species by two µ:η1:η1-syn-anti carboxylate groups forming a triangular motif; the structure of 3 embodies a tetrameric [Cu4] core, with two copper(II) ions in a distorted-octahedral coordination environment, one copper(II) ion in a distorted-trigonal-bipyramidal coordination environment, and the other copper(II) ion in a square-planar coordination environment. In fact, 2 and 3 represent rare examples of copper(II)-based multinuclear complexes showing outstanding features of rich coordination chemistry: (i) using a symmetrical dinucleating ligand, trinuclear complex 2 is generated with four- and five-coordination environments around copper(II) ions; (ii) the unsymmetrical tetranuclear complex 3 is obtained by using the same ligand with four-, five- and six-coordination environments around copper(II) ions; (iii) tetracopper(II) complex 3 shows four different bridging modes of carboxylate groups simultaneously such as µ:η2, µ:η1:η1, µ3:η2:η1:η1, and µ4:η1:η1:η1:η1, the µ4:η1:η1:η1:η1 mode of phthalate being unprecedented. The formation of these [Cu2], [Cu3], and [Cu4] complexes can be controlled by changing the exogenous ancillary ligands and pH of the reaction solutions, thus allowing an effective tuning of the self-assembly. The magnetic susceptibility measurements suggest that the copper centers in all three complexes are antiferromagnetically coupled. The thermal properties of 1-3 have been investigated by thermogravimetric and differential thermal analytical (TGA and DTA) techniques, indicating that the decomposition of all three complexes proceeds via multistep processes.

20.
J Clin Virol ; 157: 105323, 2022 12.
Article in English | MEDLINE | ID: mdl-36334368

ABSTRACT

INTRODUCTION: Although most laboratories are capable of employing established protocols to perform full-genome SARS-CoV-2 sequencing, many are unable to assess sequence quality, select appropriate mutation-detection thresholds, or report on the potential clinical significance of mutations in the targets of antiviral therapy METHODS: We describe the technical aspects and benchmark the performance of Sierra SARS-CoV-2, a program designed to perform these functions on user-submitted FASTQ and FASTA sequence files and lists of Spike mutations. Sierra SARS-CoV-2 indicates which sequences contain an unexpectedly large number of unusual mutations and which mutations are associated with reduced susceptibility to clinical stage mAbs, the RdRP inhibitor remdesivir, or the Mpro inhibitor nirmatrelvir RESULTS: To assess the performance of Sierra SARS-CoV-2 on FASTQ files, we applied it to 600 representative FASTQ sequences and compared the results to the COVID-19 EDGE program. To assess its performance on FASTA files, we applied it to nearly one million representative FASTA sequences and compared the results to the GISAID mutation annotation. To assess its performance on mutations lists, we applied it to 13,578 distinct Spike RBD mutation patterns and showed that exactly or partially matching annotations were available for 88% of patterns CONCLUSION: Sierra SARS-CoV-2 leverages previously published data to improve the quality control of submitted viral genomic data and to provide functional annotation on the impact of mutations in the targets of antiviral SARS-CoV-2 therapy. The program can be found at https://covdb.stanford.edu/sierra/sars2/ and its source code at https://github.com/hivdb/sierra-sars2.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Genome, Viral , Drug Resistance, Viral/genetics , Mutation , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Spike Glycoprotein, Coronavirus/genetics
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