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1.
Curr Drug Targets ; 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33845736

RESUMO

Gut microbiota is a complex microecosystem which is called the second genome of the human body. Herbal medicine can balance tumor-suppressing bacteria and tumor-promoting bacteria and exert its anti-cancer effect by regulating gut microbiota. Traditional Chinese medicine (TCM) has a history of thousands of years in prevention and treatment of diseases in China. In recent decades, TCM show an obvious advantage in prolonging the survival time and improving the living quality of patients with cancer. Notably, gut microbiota has become a new pathway to understanding TCM. In this review, we will focus on gut microbiota and tumor progression, especially the diversity, functionality and metabolites of gut microbiota affected by TCM in various cancer. We will also discuss the potential mechanism of gut microbiota for exploring TCM in anti-cancer effect. This article aims to comprehensively review the anti-cancer research of TCM by regulating gut microbiota, and address future perspectives and challenges of gut microbiota in TCM intervention for cancer.

2.
J Am Chem Soc ; 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33848163

RESUMO

Parastichy, the spiral arrangement of plant organs, is an example of the long-range apparent order seen in biological systems. These ordered arrangements provide scientists with both an aesthetic challenge and a mathematical inspiration. Synthetic efforts to replicate the regularity of parastichy may allow for molecular-scale control over particle arrangement processes. Here we report the packing of a supramolecular truncated cuboctahedron (TCO) into double-helical (DH) nanowires on a graphite surface with a non-natural parastichy pattern ascribed to the symmetry of the TCOs and interactions between TCOs. Such a study is expected to advance our understanding of the design inputs needed to create complex, but precisely controlled, hierarchical materials. It is also one of the few reported helical packing structures based on Platonic or Archimedean solids since the discovery of the Boerdijk-Coxeter helix. As such, it may provide experimental support for studies of packing theory at the molecular level.

3.
Front Endocrinol (Lausanne) ; 12: 604100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763027

RESUMO

Background and Aim: Circulating levels of interleukin (IL)-6, a well-known inflammatory cytokine, are often elevated in coronavirus disease-2019 (COVID-19). Elevated IL-6 levels are also observed in patients with metabolic dysfunction-associated fatty liver disease (MAFLD). Our study aimed to describe the association between circulating IL-6 levels and MAFLD at hospital admission with risk of severe COVID-19. Methods: A total of 167 patients with laboratory-confirmed COVID-19 from three Chinese hospitals were enrolled. Circulating levels of IL-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ were measured at admission. All patients were screened for fatty liver by computed tomography. Forty-six patients were diagnosed as MAFLD. Results: Patients with MAFLD (n = 46) had higher serum IL-6 levels (median 7.1 [interquartile range, 4.3-20.0] vs. 4.8 [2.6-11.6] pg/mL, p = 0.030) compared to their counterparts without MAFLD (n = 121). After adjustment for age and sex, patients with MAFLD had a ~2.6-fold higher risk of having severe COVID-19 than those without MAFLD. After adjustment for age, sex and metabolic co-morbidities, increased serum IL-6 levels remained associated with higher risk of severe COVID-19, especially among infected patients with MAFLD (adjusted-odds ratio 1.14, 95% CI 1.05-1.23; p = 0.002). There was a significant interaction effect between serum IL-6 levels and MAFLD for risk of severe COVID-19 (p for interaction = 0.008). Conclusions: Patients with MAFLD and elevated serum IL-6 levels at admission are at higher risk for severe illness from COVID-19.


Assuntos
/complicações , Fígado Gorduroso/epidemiologia , Interleucina-6/sangue , Doenças Metabólicas/fisiopatologia , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , /virologia , China/epidemiologia , Fígado Gorduroso/sangue , Fígado Gorduroso/patologia , Fígado Gorduroso/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
4.
Intern Emerg Med ; 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33765301
5.
Plant Cell Environ ; 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33763869

RESUMO

Extreme events such as drought and heatwaves are among the biggest challenges to agricultural production and food security. However, effects of cropping systems on drought resistance of arable crops via their hydraulic behaviour remain unclear. We investigated how hydraulic traits of a field-grown pea-barley (Pisum sativum L. and Hordeum vulgare L.) mixture were affected by different cropping systems, that is, organic and conventional farming with intensive or conservation tillage. Xylem vulnerability to cavitation of both species was estimated by measuring the pressure inducing 50% loss of hydraulic conductivity (P50 ), while the water stress plants experienced in the field was assessed using native percentage loss of hydraulic conductivity (nPLC). Pea and barley showed contrasting hydraulic behaviours: pea was less vulnerable to xylem cavitation and less stressed than barley; cropping systems affected xylem vulnerability of barley, but not of pea. Barley grown under conventional farming with no tillage was more vulnerable and stressed than under organic farming with intensive tillage. nPLC proved to be a valuable indicator for plant water stress. Our results highlight the impact of cropping systems on crop xylem vulnerability and drought resistance, thus plant hydraulic traits, for protecting food security under future climate. This article is protected by copyright. All rights reserved.

6.
J Cell Physiol ; 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33724469

RESUMO

Parathyroid hormone-related protein (PTHrP), the main cause of humoral hypercalcemia in malignancies, promotes cell proliferation and delays terminal cell maturation during embryonic development. Our previous study reported that PTHrP plays important roles in blastocyst formation, pluripotency gene expression, and histone acetylation during mouse preimplantation embryonic development. In this study, we further investigated the mechanism of preimplantation embryonic development regulated by PTHrP. Our results showed that Pthrp depletion decreased both the developmental rate of embryos at the cleavage stage and the cell number of morula-stage embryos. Pthrp-depleted embryos had significantly decreased levels of cyclin D1, phospho (p)-AKT (Thr308) and E2F1. However, Pthrp depletion did not cause significant changes in CDK4, ß-catenin or RUNX2 expression. In addition, our results indicated that Pthrp depletion promoted HDAC4 translocation from the cytoplasm to the nucleus in cleavage-stage embryos by stimulating the activity of protein phosphatase 2A (PP2A), which resulted in dephosphorylation of HDAC4. Taken together, these results suggest that PTHrP regulates cleavage division progression and blastocyst formation through the AKT/cyclin D1 pathway and that PTHrP modulates histone acetylation patterns through nuclear translocation of HDAC4 via PP2A-dependent HDAC4 dephosphorylation during preimplantation embryonic development in mice.

7.
J Cell Physiol ; 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33704771

RESUMO

Ca2+ participates in many important cellular processes, but the underlying mechanisms are still poorly understood, especially during oocyte maturation. First, we confirmed that calcium in the culture medium was essential for oocyte maturation. Next, various inhibitors of Ca2+ channels were applied to investigate their roles in mitochondrial Ca2+ changes and oocyte maturation. Our results showed that Trmp7, Orai, T-type Ca2+ channels and Na+ /Ca2+ exchanger complex (NCLX) were important for oocyte maturation. Trmp7 inhibition delayed germinal vesicle breakdown. Orai and NCLX inhibition significantly weakened the distribution of mitochondrial Ca2+ around the nucleus compared to the Ctrl group. Interestingly, even T-type Ca2+ channels-specific inhibitor Mibefradil blocked germinal vesicle breakdown; mitochondrial Ca2+ surrounding the nucleus still was maintained at a high level without spindle formation. Two calcium transporter inhibitors, Thapsigargin and Ruthenium Red, which have been confirmed to inhibit oocyte activation, did not significantly affect oocyte maturation. Increasing the knowledge of calcium transport may provide a basis to build on for improving oocyte in vitro maturation in human assisted reproduction clinics.

8.
Hum Cell ; 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33689158

RESUMO

To investigate the effect of the number of embryo cells on the clinical outcome of frozen-thawed embryo transfer and explore the optimal policy for decreases of multiple pregnancy rate, patients who experienced day 3 vitrified double frozen-thawed embryo transfer were retrospectively analyzed. According to the number of embryonic cells in each pre-frozen embryo, the patients were divided into six groups: 8C2 (two 8-cell embryos), 8C1- < 8C1 (one 8-cell embryo and one under-8-cell embryo), 8C1- > 8C1 (one 8-cell embryo and one over-8-cell embryo), < 8C2 (two under-8-cell embryos), < 8C1- > 8C1 (one under-8-cell embryo and one over-8-cell embryo), and > 8C2 (two over-8-cell embryos). The clinical data were analyzed. The classification decision tree was used to analyze the optimal transfer strategy. A total of 2184 cycles of day 3 vitrified double frozen-thawed embryo transfer were enrolled. In day 3 double frozen-thawed embryo cycles, the 8C2 group and 8C1- > 8C1 group had significantly (P < 0.05) higher pregnancy and multiple pregnancy rates than the other groups. No significant (P > 0.05) difference existed in the pregnancy rate and live birth rate between the 8C1- < 8C1 group, 8C2 group and 8C1- > 8C1 group, but the implantation rate and multiple pregnancy rate in the 8C1- < 8C1 group were significantly (P < 0.05) lower than in the other two groups. Compared with the multiple pregnancy rate of all cycles, the cycles in two branches showed significantly (P < 0.05) higher multiple pregnancy rates (≤ 29 years old: 8C2 / 8C1- > 8C1; 29 < age ≤ 36 years for the first transfer: 8C2 / 8C1- < 8C1 / 8C1- > 8C1, one branch showed similar rate (≤ 29 years old: 8C2 / 8C1- > 8C1) for the first transfer, and the remaining four branches demonstrated significantly (P < 0.05) lower rates. The clinical pregnancy rates before and after optimization were 51.0% vs 50.5%, and the multiple pregnancy rates were 38.5% vs 16.9%. In conclusion, the number of pre-frozen embryonic cells is an important factor affecting the clinical outcome of frozen-thawed embryo transfer in day 3 double good embryos frozen-thawed cycles. The age of patient, number of embryo cells, and the first time of transfer are the most valuable parameters for prediction. For women ≤ 29 years old, the single embryo transfer (SET) strategy was to choose an embryo ≥ 8 cells, and for women with < 29 age ≤ 36 years old, the SET strategy in the first transfer was to choose an embryo ≥ 8 cells.

9.
J Cell Physiol ; 236(7): 5352-5361, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33586215

RESUMO

In vitro culture of follicles is a promising technology to generate large quantities of mature oocytes and it could offer a novel option of assisted reproductive technologies. Here we described a 2-dimensional follicular serum-free culture system with 3-dimensional effect that can make secondary follicles develop into antral follicles (78.52%), generating developmentally mature oocytes in vitro (66.45%). The oocytes in this serum-free system completed the first meiosis; spindle assembly and chromosome congression in most oocytes matured from follicular culture were normal. However, these oocytes showed significantly lower activation and embryonic development rates, and their ability to produce Ca2+ oscillations was also lower in response to parthenogenetic activation, after which a 2-cell embryonic developmental block occurred. Oocytes matured from follicular culture displayed increased abnormal mitochondrial distribution and increased reactive oxygen species levels when compared to in vivo matured oocytes. These data are important for understanding the reasons for reduced developmental potential of oocytes matured from follicular culture, and for further improving the cultivation system.

10.
Biochem Pharmacol ; 185: 114451, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33545115

RESUMO

The secretin receptor (SCTR) is a prototypic Class B1 G protein-coupled receptor (GPCR) that represents a key target for the development of therapeutics for the treatment of cardiovascular, gastrointestinal, and metabolic disorders. However, no non-peptidic molecules targeting this receptor have yet been disclosed. Using a high-throughput screening campaign directed at SCTR to identify small molecule modulators, we have identified three structurally related scaffolds positively modulating SCTRs. Here we outline a comprehensive study comprising a structure-activity series based on commercially available analogs of the three hit scaffold sets A (2-sulfonyl pyrimidines), B (2-mercapto pyrimidines) and C (2-amino pyrimidines), which revealed determinants of activity, cooperativity and specificity. Structural optimization of original hits resulted in analog B2, which substantially enhances signaling of truncated secretin peptides and prolongs residence time of labeled secretin up to 13-fold in a dose-dependent manner. Furthermore, we found that investigated compounds display structural similarity to positive allosteric modulators (PAMs) active at the glucagon-like peptide-1 receptor (GLP-1R), and we were able to confirm cross-recognition of that receptor by a subset of analogs. Studies using SCTR and GLP-1R mutants revealed that scaffold A, but not B and C, likely acts via two distinct mechanisms, one of which constitutes covalent modification of Cys-347GLP-1R known from GLP-1R-selective modulators. The scaffolds identified in this study might not only serve as novel pharmacologic tools to decipher SCTR- or GLP-1R-specific signaling pathways, but also as structural leads to elucidate allosteric binding sites facilitating the future development of orally available therapeutic approaches targeting these receptors.

11.
J Med Microbiol ; 70(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33593474

RESUMO

This study aimed to evaluate whether the antibiotic fidaxomicin has in vitro activity against Mycobacterium tuberculosis (Mtb). 38 fully drug-sensitive Mtb strains and 34 multidrug-resistant tuberculosis (MDR-TB) strains were tested using the microplate alamar blue assay (MABA) method to determine the minimum inhibitory concentrations (MICs) for fidaxomicin and rifampicin. Fidaxomicin has high in vitro activity against Mtb and is a potential drug to treat Mtb, and MDR-TB infections in particular.


Assuntos
Antituberculosos/farmacologia , Fidaxomicina/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Rifampina/farmacologia , Tuberculose/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
12.
Chemphyschem ; 22(7): 649-656, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33567140

RESUMO

Electrostatic drag in the intramolecular Schmidt reactions of azidopropylcyclohexanones is characterized using density functional theory (DFT) calculations and direct dynamics simulations. Despite resulting from enthalpically favorable interactions, electrostatic drag slows down N2 loss during formation of bridged lactam products, an effect with implications for controlling product selectivity.

13.
Toxicology ; 452: 152705, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33548356

RESUMO

Gefitinib is a first-line anti-cancer drug for the treatment of advanced non-small cell lung cancer (NSCLC). It has been reported that gefitinib can generate several drug-related adverse effects, including nausea, peripheral edema, decreased appetite and rash. However, the reproductive toxicity of gefitinib has not been clearly defined until now. Here we assessed the effects of gefitinib on oocyte quality by examining the critical events and molecular changes of oocyte maturation. Gefitinib at 1, 2, 5 or 10 µM concentration was added to culture medium (M2). We found that gefitinib at its median peak concentration of 1 µM did not affect oocyte maturation, but 5 µM gefitinib severely blocked oocyte meiotic progression as indicated by decreased rates of germinal vesicle breakdown (GVBD) and polar body extrusion (PBE). We further showed that gefitinib treatment increased phosphorylation of CDK1 at the site of Try15, inhibited cyclin B1 entry into the nucleus, and disrupted normal spindle assembly, chromosome alignment and mitochondria dynamics, finally leading to the generation of aneuploidy and early apoptosis of oocytes. Our study reported here provides valuable evidence for reproductive toxicity of gefitinib administration employed for the treatment of cancer patients.

14.
Acta Otolaryngol ; 141(4): 392-396, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33586594

RESUMO

BACKGROUND: Although there has been progress in improving endoscopic sinus surgery (ESS), patients undergoing ESS are still at risk of postoperative bleeding. Little attention has been given to identifying specific risk factors for postoperative bleeding after ESS to treat chronic rhinosinusitis (CRS). OBJECTIVES: The aim of this study was to identify the incidence and risk factors associated with postoperative bleeding in patients who underwent ESS to treat CRS. MATERIALS AND METHODS: Six hundred and five patients with CRS who underwent ESS between 2017 and 2020 were included in this retrospective analysis. Univariate and multivariate analysis was performed to assess the association between the incidence of postoperative bleeding and the background characteristics. RESULTS: Out of 605 ESSs, 36 (6.0%) patients developed postoperative bleeding. Multiple logistic regression revealed that the use of antiplatelet and/or anticoagulant drugs, the presence of hypertension and the Lund-Mackay CT score were significantly correlated with the occurrence of postoperative bleeding. CONCLUSION: Postoperative bleeding is a common complication following ESS. The risk factors for postoperative bleeding were as follows: the use of antiplatelet and/or anticoagulant drugs, hypertension and the Lund-Mackay CT score.

15.
Mol Cell Endocrinol ; 526: 111219, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33610642

RESUMO

Prostaglandin E2 (PGE2) is a principal lipid mediator mediating various biological processes including immune responses and fluid secretion. As the first line of host defense against infection, vaginal epithelium plays orchestrated roles in vaginal innate immunity. However, the effect of PGE2 triggered by pro-inflammatory stimuli on vaginal epithelium remains elusive. This study aimed to investigate the regulatory role of PGE2 on vaginal epithelium after lipopolysaccharide (LPS) stimulation. RT-PCR and western blot analysis revealed that E-prostanoid (EP) receptors EP2 and EP4 were expressed in rat vagina. Basolateral application of PGE2 induced anion secretion mediated by cystic fibrosis transmembrane conductance regulator (CFTR) via EP-adenylate cyclase-cAMP signaling pathway in rat vaginal epithelial cells. The in vivo study showed that PGE2 promoted fluid secretion in rat vagina. Moreover, LPS stimulation facilitated cyclooxygenase-dependent PGE2 synthesis and vaginal fluid secretion in vivo. Conclusively, LPS stimulation triggered epithelium-derived PGE2 production in vaginal epithelium, leading to CFTR-mediated anion secretion and luminal flushing. This study provides valuable insights into the physiological role of PGE2 during vaginal bacterial infection.

16.
Hum Mol Genet ; 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33575778

RESUMO

Oogenesis is a highly regulated process and its basic cellular events are evolutionarily conserved. However, the time spans of oogenesis differ substantially among species. To explore these interspecies differences in oogenesis, we performed single cell RNA-sequencing on mouse and monkey female germ cells and downloaded the single cell RNA-sequencing data of human female germ cells. The cell cycle analyses indicate that the period and extent of cell cycle transitions are significantly different between the species. Moreover, hierarchical clustering of critical cell cycle genes and the interacting network of cell cycle regulators also exhibit distinguished patterns across species. We propose that differences in the regulation of cell cycle transitions may underlie female germ cell developmental allochrony between species. A better understanding of the cell cycle transition machinery will provide new insights into the interspecies differences in female germ cell developmental time spans.

17.
Waste Manag ; 123: 42-47, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33561768

RESUMO

The e-waste problem needs be tackled under a global framework, based upon the understanding that e-waste is a global issue and thus a shared responsibility. To illustrate this point, a cost-benefit analysis of metal recovery from e-waste was conducted with Europe, North America and China as representative regions of e-waste producers. The final profit associated with the entire e-waste recycling process was estimated by deducing the energy costs of metal recovery from the revenues of the manually dismantling stage and the metal recovery stage. Then, the potential job opportunities were estimated based on the final profit from the local e-waste recycling and average wage per year. Overall, profits of manually dismantling 1 ton of e-waste varied widely, but the final profits were positive. The potential job opportunities generated by local e-waste recycling ranged from 4.65 × 105 person/year for North America to 2.03 × 106 for China person/year. According to our study, the environmental load of 1 kg of e-waste would be 1-9 USD, indicating that this is the cost required to offset the environmental consequences of each kilogram of e-waste. By applying environmental load to per capita, the concept can act as a tool to encourage countries to fairly share the environmental responsibility of e-waste based on their e-waste generation. Based on this, we propose an e-waste emissions trading system that set a cap on the total amount of e-waste that could be generated globally and per country, to reduce e-waste and carbon emissions.


Assuntos
Resíduo Eletrônico , China , Análise Custo-Benefício , Resíduo Eletrônico/análise , Europa (Continente) , Políticas , Reciclagem
18.
Transl Stroke Res ; 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33629275

RESUMO

Intracerebral hemorrhage (ICH), the most lethal type of stroke, often leads to poor outcomes in the clinic. Due to the complex mechanisms and cell-cell crosstalk during ICH, the neurovascular unit (NVU) was proposed to serve as a promising therapeutic target for ICH research. This review aims to summarize the development of pathophysiological shifts in the NVU and neural-glia networks after ICH. In addition, potential targets for ICH therapy are discussed in this review. Beyond cerebral blood flow, the NVU also plays an important role in protecting neurons, maintaining central nervous system (CNS) homeostasis, coordinating neuronal activity among supporting cells, forming and maintaining the blood-brain barrier (BBB), and regulating neuroimmune responses. During ICH, NVU dysfunction is induced, along with neuronal cell death, microglia and astrocyte activation, endothelial cell (EC) and tight junction (TJ) protein damage, and BBB disruption. In addition, it has been shown that certain targets and candidates can improve ICH-induced secondary brain injury based on an NVU and neural-glia framework. Moreover, therapeutic approaches and strategies for ICH are discussed.

19.
Artigo em Chinês | MEDLINE | ID: mdl-33540989

RESUMO

With the aging of population structure, the age-related balance dysfunction increases gradually, and the injuries related fall are increasing, which cause a serious social and economic burden. In addition, dizziness or vertigo is very common clinically, and these patients also have a higher risk of falling. In order to reduce the incidence of falls, targeted prevention measures are urgently needed. In this paper, the risk assessment, preventive measures and rehabilitation strategies of falls are systematically expounded, it is hoped that it will be helpful for the prevention and treatment of falls.


Assuntos
Acidentes por Quedas , Equilíbrio Postural , Acidentes por Quedas/prevenção & controle , Envelhecimento , Tontura , Humanos , Vertigem/prevenção & controle
20.
PLoS One ; 16(2): e0243183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33621263

RESUMO

BACKGROUND: Sensitive and high throughput molecular detection assays are essential during the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The vast majority of the SARS-CoV-2 molecular assays use nasopharyngeal swab (NPS) or oropharyngeal swab (OPS) specimens collected from suspected individuals. However, using NPS or OPS as specimens has apparent drawbacks, e.g. the collection procedures for NPS or OPS specimens can be uncomfortable to some people and may cause sneezing and coughing which in turn generate droplets and/or aerosol particles that are of risk to healthcare workers, requiring heavy use of personal protective equipment. There have been recent studies indicating that self-collected saliva specimens can be used for molecular detection of SARS-CoV-2 and provides more comfort and ease of use for the patients. Here we report the performance of QuantiVirus™ SARS-CoV-2 test using saliva as the testing specimens with or without pooling. METHODS: Development and validation studies were conducted following FDA-EUA and molecular assay validation guidelines. Using SeraCare Accuplex SARS-CoV-2 reference panel, the limit of detection (LOD) and clinical performance studies were performed with the QuantiVirus™ SARS-CoV-2 test. For clinical evaluation, 85 known positive and 90 known negative clinical NPS samples were tested. Additionally, twenty paired NPS and saliva samples collected from recovering COVID-19 patients were tested and the results were further compared to that of the Abbott m2000 SARS-CoV-2 PCR assay. Results of community collected 389 saliva samples for COVID-19 screening by QuantiVirus™ SARS-CoV-2 test were also obtained and analyzed. Additionally, testing of pooled saliva samples was evaluated. RESULTS: The LOD for the QuantiVirus™ SARS-CoV-2 test was confirmed to be 100-200 copies/mL. The clinical performance studies using contrived saliva samples indicated that the positive percentage agreement (PPA) of the QuantiVirus™ SARS-CoV-2 test is 100% at 1xLOD, 1.5xLOD and 2.5xLOD. No cross-reactivity was observed for the QuantiVirus™ SARS-CoV-2 test with common respiratory pathogens. Testing of clinical samples showed a positive percentage agreement (PPA) of 100% (95% CI: 94.6% to 100%) and a negative percentage agreement (NPA) of 98.9% (95% CI: 93.1% to 99.9%). QuantiVirus™ SARS CoV-2 test had 80% concordance rate and no significant difference (p = 0.13) between paired saliva and NPS specimens by Wilcoxon matched pairs signed rank test. Positive test rate was 1.79% for 389 saliva specimens collected from local communities for COVID-19 screening. Preliminary data showed that saliva sample pooling up to 6 samples (1:6 pooling) for SARS-CoV-2 detection is feasible (sensitivity 94.8% and specificity 100%). CONCLUSION: The studies demonstrated that the QuantiVirus™ SARS-CoV-2 test has a LOD of 200 copies/mL in contrived saliva samples. The clinical performance of saliva-based testing is comparable to that of NPS-based testing. Pooling of saliva specimens for SARS-CoV-2 detection is feasible. Saliva based and high-throughput QuantiVirus™ SARS-CoV-2 test offers a highly desirable testing platform during the ongoing COVID-19 pandemic.


Assuntos
Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Saliva/virologia , Manejo de Espécimes/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Adulto Jovem
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