Highly diverse microbial community of regenerated seedlings reveals the high capacity of the bulb in lily, Lilium brownii.

Lily bulbs, which have both nutrient storage and reproductive functions, are a representative group of plants for studying the maintenance and transfer of plant-associated microbiomes. In this study, a comparison of the microbial composition of bulbs and their regenerated seedlings cultured under aseptic conditions, as well as subcultured seedlings that succeeded five times, was examined by amplicon sequencing. A total of 62 bacterial taxa and 56 fungal taxa were found to be transferred to the 5th generation in seedlings, which are the core microbiome of lily. After the regeneration of seedlings from bulbs, there was a significant increase in the number of detectable microbial species, and after 1, 3, and 5 successive generations, there was a decrease in the number of detectable species. Interestingly, some "new" microorganisms appeared in each generation of samples; for instance, 167 and 168 bacterial operational taxonomic units (OTUs) in the 3rd and 5th generations of seedlings that were not detected in either bulbs or seedlings of the previous two generations. These results suggest that bulbs can maintain a high diversity of microorganisms, including some with ultra-low abundance, and have a high transfer capacity to tuck shoots through continuous subculture. The diversity and maintenance of the microbiome can provide the necessary microbial reservoir support for regenerating seedlings. This habit of maintaining low abundance and high diversity may be biologically and ecologically critical for maintaining microbiome stability and function due to the sequestration nature of the plant.

A CRISPR-Cas12a-based specific enhancer for more sensitive detection of SARS-CoV-2 infection

High Ct-values falling in the grey zone are frequently encountered in SARS-CoV-2 detection by real-time reverse transcription PCR (rRT-PCR) and have brought urgent challenges in diagnosis of samples with low viral load. Based on the single-stranded DNA reporter trans-cleavage activity by Cas12a upon target DNA recognition, we create a Specific Enhancer for detection of PCR-amplified Nucleic Acids (SENA) to confirm SARS-CoV-2 detection through specifically targeting its rRT-PCR amplicons. SENA is highly sensitive, with its limit of detection being at least 2 copies/reaction lower than that of the corresponding rRT-PCR, and highly specific, which identifies both false-negative and false-positive cases in clinic applications. SENA provides effective confirmation for nucleic acid amplification-based molecular diagnosis, and may immediately eliminate the uncertainty problems of rRT-PCR in SARS-CoV-2 clinic detection. One Sentence SummaryCRISPR-Cas12a-based COVID-19 diagnosis.

Sensitivity evaluation of 2019 novel coronavirus (SARS-CoV-2) RT-PCR detection kits and strategy to reduce false negative

An ongoing outbreak of pneumonia associated with SARS-CoV-2 has now been confirmed globally. In absence of effective vaccines, infection prevention and control through diagnostic testing and quarantine is critical. Early detection and differential diagnosis of respiratory infections increases the chances for successful control of COVID-19 disease. The nucleic acid RT-PCR test is regarded as the current standard for molecular diagnosis with high sensitivity. However, the highest specificity confirmation target ORF1ab gene is considered to be less sensitive than other targets in clinical application. In addition, a large amount of recent evidence indicates that the initial missed diagnosis of asymptomatic patients with SARS-CoV-2 and discharged patients with "re-examination positive" may be due to low viral load, and the ability of rapid mutation of coronavirus also increases the rate of false negative results. We aimed to evaluate the sensitivity of different nucleic acid detection kits so as to make recommendations for the selection of validation kit, and amplify the suspicious result to be reportable positive by means of simple continuous amplification, which is of great significance for the prevention and control of the current epidemic and the discharge criteria of low viral load patients.

Rapid Detection of SARS-CoV-2 Using Reverse transcription RT-LAMP method

Corona Virus Disease 2019 (COVID-19) is a recently emerged life-threatening disease caused by SARS-CoV-2. Real-time fluorescent PCR (RT-PCR) is the clinical standard for SARS-CoV-2 nucleic acid detection. To detect SARS-CoV-2 early and control the disease spreading on time, a faster and more convenient method for SARS-CoV-2 nucleic acid detecting, RT-LAMP method (reverse transcription loop-mediated isothermal amplification) was developed. RNA reverse transcription and nucleic acid amplification were performed in one step at 63 {degrees}C isothermal conditions, and the results can be obtained within 30 minutes. ORF1ab gene, E gene and N gene were detected at the same time. ORF1ab gene was very specific and N gene was very sensitivity, so they can guarantee both sensitivity and specificity for SARS-CoV-2. The sensitivity of RT-LAMP assay is similar to RT-PCR, and specificity was 99% as detecting 208 clinical specimens. The RT-LAMP assay reported here has the advantages of rapid amplification, simple operation, and easy detection, which is useful for the rapid and reliable clinical diagnosis of SARS-CoV-2.

Comparative study of different bandaging and hemostasis methods after percutaneous coronary intervention through femoral artery / 中国实用护理杂志

ObjectiveTo evaluate the safety and superiority of dressings and bandage compression method for patients after percutaneous coronary intervention through femoral artery.MethodsA total of 648 patients who received percutaneous coronary intervention through femoral artery were randomly divided into three groups: the modified group (224 cases), the routine group (213 cases) and the haemostat group (211 cases), they each adopted modified dressings and bandage compression method, the traditional oppression hemostatic method, and arterial oppression with hemostat method. The unarmed oppression time, expenditure, braking time, and complications were observed and analyzed statistically.ResultsThere was no significant difference in braking time and local vascular complications of the three groups. Compared with the routine group, the modified group reduced the unarmed oppression time and the medical staffs workload; compared with the hemostat group, it reduced the expenditure.ConclusionsImproved dressings and bandage compression method can reduce the unarmed oppression time and expenditure, it is an ideal local hemostasis method for patients undergoing percutaneous coronary intervention through femoral artery, and is worthy of clinical application.