OBJECTIVESTo study the biological behavior of hepatocarcinoma stem cells in rats.

METHODSPrimary liver carcinomas were induced in rats using diethylnitrosamine. Tumor cells from 8 rats were separated according to rats oval cell (OVC) markers CD34, c-Kit, Thy-1, AFP, CK7, CK8, CK14, CK18, CK19 and GGT and then they were separately injected into the livers of nude mice. The tumors grown from the different subpopulation of OVC markers in the nude mice livers (10 OVC markers negative or positive cells) were weighted 1 month after the inoculations. The hepatocarcinoma cell subpopulations with higher ability in causing tumor growths were further studied in vitro. The cell cycles and DNA content of those subpopulation cells were investigated using flow cytometry.

RESULTS(1) Subpopulation cells with CK7(-), Thy-1(+) and AFP(+) markers had a higher ability in causing tumors in nude mice; (2) Subpopulation cells, exhibiting characters of TSC, had a low growth rate in vitro.

CONCLUSIONS(1) Different subpopulations of hepatocarcinoma cells had different abilities in causing tumors in rats. Some subpopulation cells, such as CK7(-), Thy-1(+) and AFP(+) cells, have characteristics of tumor stem cells. (2) The hepatocarcinoma stem cells may have a low growth rate in vitro.

Animals ; Cell Cycle ; Cyclin-Dependent Kinases ; biosynthesis ; Liver Neoplasms, Experimental ; pathology ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplastic Stem Cells ; pathology ; physiology ; Rats ; Rats, Sprague-Dawley ; Thy-1 Antigens ; biosynthesis ; Tumor Cells, Cultured ; alpha-Fetoproteins ; biosynthesis

OBJECTIVEElectron microscopical study of infected cells to identify the pathogenic agent of SARS.

METHODSVero E6 cells infected with lung autopsy samples or nasopharyngeal swabs from SARS patients of Beijing and Guangzhou were inoculated. The supernatant and cultured cells exhibiting identifiable cytopathic effect (CPE) were prepared for electron microscopic study.

RESULTSExamination of CPE cells on thin-section revealed characteristic coronavirus particles within the cisternae of endoplasmic reticulum, Golgi apparatus, vesicles and extracellular space. They were mainly spherical or oval in shape, annular or dense, about 80 nm in diameter. Negative-stain electron microscopy identified coronavirus particles in culture supernatant, 80 - 120 nm in diameter, with club-shaped surface projections. Elongated, rod-, kidney- or other irregular shaped virons with the size of 100 - 200 nm by 60 - 90 nm were also found in the cultured cells infected with the lung samples from the Guangdong patients. Infectious virons entered cells by endocytosis or membrane fusion and released through a budding process.

CONCLUSIONThese data indicate a novel coronavirus as the causative agent of SARS. Most viral particles showed typical characteristics of coronavirus. The potential role of special shape viruses is expected to be further investigated.

Animals ; Cercopithecus aethiops ; Humans ; Microscopy, Electron ; SARS Virus ; ultrastructure ; Severe Acute Respiratory Syndrome ; virology ; Vero Cells

Systemic lupus erythematosus combined with chorea is relatively rare in China,and there are no unified diagnostic criteria or specific ancillary tests.Therefore,it is confirmed by exclusionary clinical diagnosis.To improve the understanding of this disease among rheumatologists,we report the clinical data of a patient with systemic lupus erythematosus combined with chorea admitted to the Department of Rheumatology and Immunology in the First Affiliated Hospital of Jinan University in January 2022.Furthermore,we review the relevant literature in the past 10 years and summarize the clinical features of these cases.
Humans ; Chorea/diagnosis* ; Lupus Erythematosus, Systemic/complications* ; China ; Hospitalization ; Hospitals

We report a complete genomic sequence of rare isolates (minor genotype) of the SARS-CoV from SARS patients in Guangdong, China, where the first few cases emerged. The most striking discovery from the isolate is an extra 29-nucleotide sequence located at the nucleotide positions between 27,863 and 27,864 (referred to the complete sequence of BJ01) within an overlapped region composed of BGI-PUP5 (BGI-postulated uncharacterized protein 5) and BGI-PUP6 upstream of the N (nucleocapsid) protein. The discovery of this minor genotype, GD-Ins29, suggests a significant genetic event and differentiates it from the previously reported genotype, the dominant form among all sequenced SARS-CoV isolates. A 17-nt segment of this extra sequence is identical to a segment of the same size in two human mRNA sequences that may interfere with viral replication and transcription in the cytosol of the infected cells. It provides a new avenue for the exploration of the virus-host interaction in viral evolution, host pathogenesis, and vaccine development.
Base Sequence ; China ; Cluster Analysis ; Gene Components ; Genetic Variation ; Genome, Viral ; Genotype ; Molecular Sequence Data ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; SARS Virus ; genetics ; Sequence Analysis, DNA ; Severe Acute Respiratory Syndrome ; genetics