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

Background: Acitretin and matrine have been used in the treatment of psoriasis in China. This study was designed to investigate the role and related mechanisms of matrine alone and in combination with acitretin in the treatment of psoriasis in vitro and in vivo. Methods: HaCaT cells were treated with matrine at different concentrations of 0 (blank control), 0.2, 0.4, 0.8, and 1.6 mg/mL for 24, 48, 72 h, respectively. 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium cell viability assay was used to assess the growth and proliferation of HaCaT cells. Cell cycle and apoptosis were detected by flow cytometry. Expression of protein was detected by Western blotting. Autophagy was observed by transmission electron microscopy. Then HaCaT cells were assigned to normal saline (NS) control group, matrine (0.4 mg/mL) group, acitretin (10 μmol/L) group, and matrine plus acitretin group, and the above methods were repeated. In animal experiments, the cumulative score (erythema, scaling, thickening) as a measure of the severity of inflammation was used to measure the skin performance of mice after treated with matrine 50 mg/kg, acitretin 4.5 mg/kg or combination of the two drugs on the psoriasis-like mouse models, respectively. Pathological findings of the lesions were observed, and the protein expressions in the lesions were detected by immunohistochemistry. Results: Cell proliferation inhibition was seen in HaCaT cells with treatment of matrine in a dose- and time-dependent manner (P < 0.01, respectively). Cell cycle G0/G1 phase arrest was observed in a dose-dependent way (P < 0.01). The expression of p21 (P < 0.05), LC3II/I (P < 0.01), and Beclin 1 (P < 0.01) increased and the expression of cyclin D1 (P < 0.05) decreased with increasing doses of matrine. Compared with the blank control, more autophagosomes were seen in HaCaT cells treated with matrine at 0.4 mg/mL by transmission electron microscopy (2.667 ± 1.202 vs. 21.33 ± 1.453, t = 9.899, P < 0.01). Cell proliferation inhibition and degree of the G0/G1 phase arrest was significantly higher in matrine plus acitretin group than those in matrine, acitretin, or the NS control group (P < 0.01, respectively). Compared with matrine or acitretin group, the expression of p21 (P < 0.05, P < 0.05) and LC3II/I (P < 0.01, P < 0.05) in matrine plus acitretin group increased significantly and the expression of cyclin D1 (P < 0.01, P < 0.05) and p62 (P < 0.05, P < 0.05) was reduced significantly. Compared with matrine or acitretin, matrine plus acitretin significantly down-regulated the phosphorylation of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway (P < 0.05) and its downstream p-p70S6K (P < 0.05). In addition, the cumulative score of mice in the matrine plus acitretin group was significantly better than that in the matrine or acitretin group (1.480 ± 0.230 vs. 2.370 ± 0.241, P < 0.01; 1.480 ± 0.230 vs. 2.888 ± 0.341, P < 0.01). The expression of LC3 protein in the matrine plus acitretin group was also higher than that in the matrine, acitretin, or the NS control group (P < 0.05, respectively). Conclusions Matrine has therapeutic potentials for psoriasis. Matrine and acitretin show synergistic effect via cell cycle arrest and autophagy induction by PI3K/Akt/mTOR pathway.

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

Antibodies, Monoclonal, Humanized ; China ; Humans ; Pilot Projects ; Psoriasis/drug therapy* ; Severity of Illness Index ; Treatment Outcome

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