Development and validation of nucleic acid tests to diagnose Aleutian mink disease virus

In this work, we discovered a new phenomenon—asymptomatic COVID-19 infection, or covert case, during the pandemic. All the 3 patients had a history of exposure, with no symptoms, and no abnormalities were found in computed tomography scan or lab tests. Except for case 2, the other patients’ severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) nucleic acid tests were negative. But their anti-SARS-COV-2 nucleocapsid antibody showed a dynamic trend, consistent with the process of virus infection and clearance. A growing number of asymptomatic or covert cases need more attention. Lack of surveillance may lead to another outbreak. We hope to demonstrate our cases to attract the attention of governments or health authorities that covert cases should be the focus as well.

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Nitrocellulose-bound achromopeptidase for point-of-care nucleic acid tests

Scientific Reports ◽

10.1038/s41598-021-85481-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Georgios Chondrogiannis ◽

Shirin Khaliliazar ◽

Anna Toldrà ◽

Pedro Réu ◽

Mahiar M. Hamedi

Keyword(s):

Nucleic Acid ◽

Sample Preparation ◽

Point Of Care ◽

Dna Amplification ◽

Recombinase Polymerase Amplification ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Enzymatic Function ◽

Modern Biotechnology ◽

Nucleic Acid Tests

AbstractEnzymes are the cornerstone of modern biotechnology. Achromopeptidase (ACP) is a well-known enzyme that hydrolyzes a number of proteins, notably proteins on the surface of Gram-positive bacteria. It is therefore used for sample preparation in nucleic acid tests. However, ACP inhibits DNA amplification which makes its integration difficult. Heat is commonly used to inactivate ACP, but it can be challenging to integrate heating into point-of-care devices. Here, we use recombinase polymerase amplification (RPA) together with ACP, and show that when ACP is immobilized on nitrocellulose paper, it retains its enzymatic function and can easily and rapidly be activated using agitation. The nitrocellulose-bound ACP does, however, not leak into the solution, preventing the need for deactivation through heat or by other means. Nitrocellulose-bound ACP thus opens new possibilities for paper-based Point-of-Care (POC) devices.

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Aptamer-targeting of Aleutian mink disease virus (AMDV) can be an effective strategy to inhibit virus replication

Scientific Reports ◽

10.1038/s41598-021-84223-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Taofeng Lu ◽

Hui Zhang ◽

Jie Zhou ◽

Qin Ma ◽

Wenzhuo Yan ◽

...

Keyword(s):

Disease Virus ◽

Magnetic Beads ◽

Inhibitory Effect ◽

Three Dimensions ◽

Economic Losses ◽

Effective Vaccine ◽

Stem Loop ◽

Aleutian Mink Disease Virus ◽

Random Library

AbstractAleutian mink disease (AMD), which is caused by Aleutian mink disease virus (AMDV), is an important contagious disease for which no effective vaccine is yet available. AMD causes major economic losses for mink farmers globally and threatens some carnivores such as skunks, genets, foxes and raccoons. Aptamers have exciting potential for the diagnosis and/or treatment of infectious viral diseases, including AMD. Using a magnetic beads-based systemic evolution of ligands by exponential enrichment (SELEX) approach, we have developed aptamers with activity against AMDV after 10 rounds of selection. After incubation with the ADVa012 aptamer (4 μM) for 48 h, the concentration of AMDV in the supernatant of infected cells was 47% lower than in the supernatant of untreated cells, whereas a random library of aptamers has no effect. The half-life of ADVa012 was ~ 32 h, which is significantly longer than that of other aptamers. Sequences and three dimensions structural modeling of selected aptamers indicated that they fold into similar stem-loop structures, which may be a preferred structure for binding to the target protein. The ADVa012 aptamer was shown to have an effective and long-lasting inhibitory effect on viral production in vitro.

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Nucleic Acid Tests for BK Polyomavirus Is Critical in Renal Transplant Recipients

Transplantation Proceedings ◽

10.1016/j.transproceed.2018.03.100 ◽

2018 ◽

Vol 50 (8) ◽

pp. 2489-2492

Author(s):

Y.-L. Chang ◽

Y.-T. Cheng ◽

T.-C. Chen ◽

Y.-S. Chien ◽

W.-C. Lee ◽

...

Keyword(s):

Nucleic Acid ◽

Renal Transplant ◽

Renal Transplant Recipients ◽

Transplant Recipients ◽

Bk Polyomavirus ◽

Nucleic Acid Tests

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Efficacy and Safety of Lianhuaqingwen Capsules for the Prevention of Coronavirus Disease 2019: A Prospective Open-Label Controlled Trial

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/7962630 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Xiaowei Gong ◽

Boyun Yuan ◽

Yadong Yuan ◽

Fengju Li

Keyword(s):

Nucleic Acid ◽

Treatment Group ◽

Close Contact ◽

Controlled Trial ◽

Control Group ◽

Open Label ◽

Medical Observation ◽

Observation Period ◽

Close Contacts ◽

Nucleic Acid Tests

Coronavirus disease 2019 (COVID-19) has become a global pandemic. Community and close contact exposures continue to drive the COVID-19 pandemic. There is no confirmed effective treatment for suspected cases and close contacts. Lianhuaqingwen (LH) capsules, a repurposed Chinese herbal product that is currently on the market, have proven effective for influenza and COVID-19. To determine the safety and efficacy of LH capsules for the prevention of COVID-19, we conducted a prospective open-label controlled trial of LH capsules on subjects who had close contact with people infected with COVID-19. Subjects received LH capsules (4 capsules, three times daily) or the usual medical observation for 14 days. The primary endpoint was the rate of positive nucleic acid tests of nasal and pharyngeal swabs during the quarantine medical observation period. We included 1976 patients, including 1101 in the treatment group and 875 in the control group. The rate of positive nucleic acid tests in the treatment group was significantly lower than that in the control group (0.27% vs. 1.14%, respectively; mean difference: −0.87%; 95% CI: −1.83 to −0.13; p = 0.0174 ) during the quarantine medical observation period (14 days). Among subjects with different close contact states, there was no significant difference in the rate of positive nucleic acid test results among close contacts in the treatment group and the control group (6.45% vs. 11.43%, respectively; p = 0.6762 ). Among secondary close contacts, the rate of positive nucleic acid tests in the treatment group was significantly lower than that in the control group (0.09% vs. 0.71%, respectively; p = 0.0485 ). No serious adverse events were reported. Taken together, and in light of the safety and effectiveness profiles, these results show that LH capsules can be considered to prevent the progression of COVID-19 after close contact with an infected person. This trial is registered with ChiCTR2100043012.

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Key points of technical review for the registration of SARS-CoV-2 nucleic acid tests in China

Bioanalysis ◽

10.4155/bio-2021-0166 ◽

2021 ◽

Author(s):

Hongran Li ◽

Tong Jiao ◽

Peirong Wang ◽

Juanjuan An ◽

Gang Deng ◽

...

Keyword(s):

Nucleic Acid ◽

Medical Device ◽

Product Safety ◽

Technical Review ◽

Key Points ◽

Safety Effectiveness ◽

Unified Command ◽

And Control ◽

Nucleic Acid Tests

In response to the outbreak of COVID-19, in accordance with the principles of ‘unified command, early involvement, prompt review and scientific approval’ as well as the requirements of ensuring product safety, effectiveness and controllable quality, the Center for Medical Device Evaluation (CMDE) has issued Key Points of Technical Review for the Registration of SARS-CoV-2 Nucleic Acid Tests ( Key Points) to provide the requirements of tests. Because of the sustainability of the pandemic, more efforts and attempts are needed for SARS-CoV-2 detection and control. This article interprets the Key Points issued by the CMDE and provides certain refinements to wider audiences.

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