An epidemic of respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began in China and has spread to other countries. 1 Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) of nasopharyngeal swabs typically has been used to confirm the clinical diagnosis. 2 However, whether the virus can be detected in specimens from other sites, and therefore potentially transmitted in other ways than by respiratory droplets, is unknown.Methods | We investigated the biodistribution of SARS-CoV-2 among different tissues of inpatients with coronavirus disease 2019 (COVID-19) diagnosed based on symptoms and radiology and confirmed by SARS-CoV-2 detection. This study was approved by the ethics commissions of the participating hospitals, with a waiver of informed consent.Patients with specimens collected based on clinical indications from 3 hospitals in the Hubei and Shandong provinces and Beijing, China, from January 1 through February 17, 2020, were included. Pharyngeal swabs were collected from most patients 1 to 3 days after hospital admission. Blood, sputum, feces, urine, and nasal samples were collected throughout the illness. Bronchoalveolar lavage fluid and fibrobronchoscope brush biopsy were sampled from patients with severe illness or undergoing mechanical ventilation. RNA was extracted from clinical specimens and determined by rRT-PCR targeting the open reading frame 1ab gene of SARS-CoV-2 as previously described. 2 The cycle threshold values of rRT-PCR were used as indicators of the copy number of SARS-CoV-2 RNA in specimens with lower cycle threshold values corresponding to higher viral copy numbers. A cycle threshold value less than 40 is interpreted as positive for SARS-CoV-2 RNA. Four SARS-CoV-2 positive fecal specimens with high copy numbers were cultured, and then electron microscopy was performed to detect live virus. Patterns in a subgroup of patients with multiple specimens collected during hospitalization were explored.

Sturgeons and paddlefishes (Acipenseriformes) occupy the basal position of ray-finned fishes, although they have cartilaginous skeletons as in Chondrichthyes. This evolutionary status and their morphological specializations make them a research focus, but their complex genomes (polyploidy and the presence of microchromosomes) bring obstacles and challenges to molecular studies. Here, we generated the first high-quality genome assembly of the American paddlefish (Polyodon spathula) at a chromosome level. Comparative genomic analyses revealed a recent species-specific whole-genome duplication event, and extensive chromosomal changes, including head-to-head fusions of pairs of intact, large ancestral chromosomes within the paddlefish. We also provide an overview of the paddlefish SCPP (secretory calcium-binding phosphoprotein) repertoire that is responsible for tissue mineralization, demonstrating that the earliest flourishing of SCPP members occurred at least before the split between Acipenseriformes and teleosts. In summary, this genome assembly provides a genetic resource for understanding chromosomal evolution in polyploid nonteleost fishes and bone mineralization in early vertebrates.

Rehmannia is a non-parasitic genus in Orobanchaceae including six species mainly distributed in central and north China. Its phylogenetic position and infrageneric relationships remain uncertain due to potential hybridization and polyploidization. In this study, we sequenced and compared the complete chloroplast genomes of six Rehmannia species using Illumina sequencing technology to elucidate the interspecific variations. Rehmannia plastomes exhibited typical quadripartite and circular structures with good synteny of gene order. The complete genomes ranged from 153,622 bp to 154,055 bp in length, including 133 genes encoding 88 proteins, 37 tRNAs, and 8 rRNAs. Three genes (rpoA, rpoC2, accD) have potentially experienced positive selection. Plastome size variation of Rehmannia was mainly ascribed to the expansion and contraction of the border regions between the inverted repeat (IR) region and the single-copy (SC) regions. Despite of the conserved structure in Rehmannia plastomes, sequence variations provide useful phylogenetic information. Phylogenetic trees of 23 Lamiales species reconstructed with the complete plastomes suggested that Rehmannia was monophyletic and sister to the clade of Lindenbergia and the parasitic taxa in Orobanchaceae. The interspecific relationships within Rehmannia were completely different with the previous studies. In future, population phylogenomic works based on plastomes are urgently needed to clarify the evolutionary history of Rehmannia.