The genome of Stephania japonica provides insights into the biosynthesis of cepharanthine.

Stephania japonica is an early-diverging eudicotyledon plant with high levels of cepharanthine, proven to be effective in curing coronavirus infections. Here, we report a high-quality S. japonica genome. The genome size is 688.52 Mb, and 97.37% sequences anchor to 11 chromosomes. The genome comprises 67.46% repetitive sequences and 21,036 genes. It is closely related to two Ranunculaceae species, which diverged from their common ancestor 55.90-71.02 million years ago (Mya) with a whole-genome duplication 85.59-96.75 Mya. We further reconstruct ancestral karyotype of Ranunculales. Several cepharanthine biosynthesis genes are identified and verified by western blot. Two genes (Sja03G0243 and Sja03G0241) exhibit catalytic activity as shown by liquid chromatography-mass spectrometry. Then, cepharanthine biosynthesis genes, transcription factors, and CYP450 family genes are used to construct a comprehensive network. Finally, we construct an early-diverging eudicotyledonous genome resources (EEGR) database. As the first genome of the Menispermaceae family to be released, this study provides rich resources for genomic studies.

Infection caused by Cupriavidus gilardii in a convalescent COVID-19 patient.

Cupriavidus gilardii is an aerobic, gram-negative bacillus that can opportunistically infect immunocompromised patients or those undergoing invasive procedures. We reported a case caused by C. gilardii in a previously basic healthy 78-year-old male, who had COVID-19 and had used corticosteroids recently. The bacterium was identified as C. gilardii by the metagenomic next-generation sequencing from the patient's bronchoalveolar lavage fluid and blood. In addition, this is the first time that we isolated C. gilardii from bronchoalveolar lavage fluid, which provides clinical experience in rare bacterial infections.

Methylmalonic acid levels in serum, exosomes, and urine and its association with cblC type methylmalonic acidemia-induced cognitive impairment.

Background: The cblC type methylmalonic acidemia is the most common methylmalonic acidemia (MMA) in China. The biochemical characteristics of this disease include elevated methylmalonic acid and homocysteine (HCY), increased propionylcarnitine (C3), decreased free carnitine (C0). In this study, we aimed to clarify the roles of these biomarkers in cblC-MMA induced cognitive impairment and evaluate the capacity of methylmalonic acid in different fluids or exosomes to distinguish cblC-MMA induced cognitive impairment. Methods: 15 non-inherited hyperhomocysteinemia (HHcy) patients, 42 cblC-MMA patients and 57 age- and sex-matched healthy children were recruited in this study. The levels of HCY were detected by an automatic immune analyzer. The levels of acylcarnitines and methylmalonic acid were detected by tandem mass spectrometer. Results: The main findings were all biomarkers as HCY, acylcarnitines and methylmalonic acid had capacities for distinguishing patients with cblC-MMA induced cognitive impairment from healthy children. The methylmalonic acid in different fluids or exosomes had good performances for distinguishing patients with cblC-MMA induced cognitive impairment from HHcy patients. The methylmalonic acid in serum exosomes and neuronal-derived exosomes were able to distinguishing cblC-MMA patients with cognitive impairment from patients without cognitive impairment. The methylmalonic acid in neuronal-derived exosomes might be helpful to evaluate the severity of cblC-MMA induced cognitive impairment. Discussion: Methylmalonic acid levels in serum exosomes, especially in serum neuronal-derived exosomes, serve as potential biomarkers for distinguishing cblC-MMA induced cognitive impairment.

A circular RNA from NFIX facilitates oxidative stress-induced H9c2 cells apoptosis.

Myocardial infarction is the leading cause of death worldwide, and cardiomyocyte apoptosis during myocardial infarction and reperfusion is a significant factor of poor prognosis. As important regulatory molecules, biofunctions of circRNAs in the pathogenesis of myocardial infarction remain elusive. To confirm the expression level and biological function of circNFIX in cardiomyocytes upon oxidative stress. Divergent polymerase chain reaction and Sanger sequencing were performed to verify the circular structure. The stability of circNFIX was confirmed by RNase R treatment and actinomycin D assay. In order to simulate oxidative stress during myocardial infarction, H9c2 cells were subjected to hydrogen peroxide and hypoxia stimulation. In vivo, mouse models of myocardial ischemia were established. The biological function of circNFIX in cardiomyocytes was investigated through loss- and gain-of-function assays, and cardiomyocyte apoptosis level was detected by the terminal deoxyribonucleotidyl transferase-mediated TdT-mediated dUTP nick end labeling assay and Western blot. CircNFIX is abundant, conserved, and stable in H9c2 cells. The expression of circNFIX was significantly downregulated in cardiomyocytes subjected to oxidative stress. Enforced CircNFIX promotes H9c2 cells apoptosis induced by hydrogen peroxide, in sharp contrast to circNFIX knockdown. In this study, we found that circNFIX served as a pro-apoptosis factor in cardiomyocyte apoptosis. CircNFIX possesses potential to be the biomarker and therapeutic target in myocardial infarction.

Detection and Identification of Leachables in Vaccine from Plastic Packaging Materials Using UPLC-QTOF MS with Self-Built Polymer Additives Library.

The direct contact of plastic parts with the medical products raises the possibility that plastic-related contaminants (leachables) may be present in the finished medical product. The leachable components from plastic materials may impact the safety and efficacy of the final medical product, so identification and determination of the leachables are essential for the safety assessment of medical products. A method to identify main leachables-polymer additives in medical products was developed by ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF MS) and a self-built library. The library contains 174 additives and the information on their names, formulas, structures, retention times, fragments, classifications, origin, and corresponding MS(E) and MSMS spectra. The reliability of the construction process of the library was guaranteed by the system stability and suitability test. Identification parameters of library application, such as mass error, retention times, fragments, and isotope pattern, were evaluated. Leachables in real vaccine and the intermediates were identified using automatic library searching. In vaccine, the peak m/z 239.0887 that could not be assigned by the library was identified as dimethyl 2-hydroxy-1,3-cyclohexanedicarboxylate using a series of elucidation tools. As a result, the concentrations of leachables in vaccine and the intermediates ranged from 0.85 to 21.91 µg/L.

[Determination of Sudan Red I-IV in duck egg yolk using ultra performance liquid chromatography-tandem mass spectrometry].

A method of the simultaneous analysis of Sudan Red I - IV in duck egg yolk was developed with an ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Acetonitrile was used to extract the residues from duck egg yolk, and water was added into the extract to precipitate impurities such as protein and fat. The supernatant was detected by the UPLC-MS/MS after refrigeration and centrifugation. The sample was separated on a Waters Acquity BHE C18 column, and detected by MS/MS with the multiple reaction monitoring (MRM) mode. The limits of detection (LOD) were 0.05 microg/L in the standard solution, and 10 microg/kg of the four substances in the sample spiked with Sudan Red I - IV. The average recoveries were between 50.2% - 101.3% at three spiking levels of 100.0, 200.0, 300.0 microg/kg. The experiment results show that this method is of high sensitivity, low LOD, better determination capacity and shorter analysis time. The method could meet the high-throughout detection of Sudan Red in food samples.