OBJECTIVESevere acute respiratory syndrome (SARS) is an emerging infectious disease that first manifested in humans in November 2002. The SARS-associated coronavirus (SARS-CoV) has been identified as the causal agent, but the pathology and pathogenesis are still not quite clear.

METHODSPost-mortem lung samples from six patients who died from SARS from April to July 2003 were studied by light and electron microscopy, Masson trichromal staining and immunohistochemistry. Evidence of infection with the SARS-CoV was determined by reverse-transcription PCR (RT-PCR) , serological examination and electron microscopy.

RESULTSFour of six patients had serological and RT-PCR evidence of recent infection of SARS-CoV. Morphologic changes are summarized as follows: (1) Diffuse and bilateral lung consolidation was seen in all patients (6/6) with increasing lung weight. (2) Diffuse alveolar damage was universal (6/6) with hyaline membrane formation (6/6), intra-alveolar edema/hemorrhage (6/6), fibrin deposition (6/6), pneumocyte desquamation (6/6). A marked disruption in the integrity of the alveolar epithelium was confirmed by immunostaining for the epithelial marker AE1/AE3 (6/6). (3) Type II pneumocytes, with mild hyperplasia, atypia, cytomegaly with granular amphophilic cytoplasm and intracytoplasmic lipid accumulation (5/6). (4) Giant cells in the alveoli were seen in five of 6 patients (5/6) , most of which were positive for the epithelial marker AE1/AE3 (5/6), but some cells were positive for the macrophage marker CD68(2/6). (5) A pronounced increase of macrophages were seen in the alveoli and the interstitium of the lung (6/6), which was confirmed by histological study and immunohistochemistry. (6) Haemophagocytosis was present in five of the 6 patients(5/6). (7) Lung fibrosis was seen in five patients(5/6), with alveolar septa and interstitium thickening(5/6), intraalveolar organizing exudates (6/6) and pleura thickening (4/6). Proliferation of collagen was confirmed by Masson trichromal staining, most of which was type III collagen by immunostaining. The formation of distinctive fibroblast/myofibroblast foci was seen in five patients (5/6) by light microscopy and immunochemistry. (8) Squamous metaplasia of bronchial mucosa was seen in five patients(5/6). (9) Thrombi was seen in all patients(6/6). (10) Accompanying infection was present in two patients, one was bacteria, the other was fungus. In addition, electron microscopy revealed viral particles in the cytoplasm of alveolar epithelial cells and endothelial cells corresponding to coronavirus.

CONCLUSIONDirect injury of SARS-CoV on alveolar epithelium, prominent macrophage infiltration and distinctive fibroblast/myofibroblast proliferation may play major roles in the pathogenesis of SARS.

Adult ; Antibodies, Monoclonal ; metabolism ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Epithelium ; pathology ; Female ; Humans ; Keratins ; immunology ; Lung ; pathology ; ultrastructure ; virology ; Male ; Middle Aged ; Pulmonary Alveoli ; pathology ; Pulmonary Fibrosis ; etiology ; pathology ; SARS Virus ; isolation & purification ; Severe Acute Respiratory Syndrome ; complications ; metabolism ; pathology ; virology

Objective To construct the pEGFP-C1-CXCL1 eukaryotic expression vector and to investigate the effect of CXCL1 on the proliferation of HepG2 cells under endoplasmic reticulum stress ( ERS).Methods Fragments of CXCL1 were obtained from the cDNA library of HepG2 cells before CXCL1 was cloned into a pEGFP-C1 vector for a recombinant plasmid pEGFP-C1-CXCL1 which was screened and identified by PCR and sequence alignment .Then,the recombinant plas-mid of pEGFP-C1-CXCL1 was transfected into human 293 T cell line and the expression of CXCL 1 was detected by fluores-cence microscopy and Western blotting.pEGFP-C1-CXCL1was furhter transfected into HepG2 cells, and CCK8 was used to detect the inhibitory effect of CXCL1 on tumor proliferation induced by TM in hepatocellular carcinoma .Results pEGFP-C1-CXCL1 was vertified by sequencing analysis .Fluorescence microscopy showed that pEGFP-C1-CXCL1 was transfected into 293T.CXCL1 expression was detected by Western blotting .CCK8 showed that TM inhibited tumor proliferation , while overexpression of CXCL1 decreased the inhabitory rate on cell proliferation of HepG 2 cells under ER stress compared to pEGFP-C1 group and the control group .Conclusion A recombinant pEGFP-C1-CXCL1 plasmid is successfully constructed that can be expressed stably in human 293T cells.Overexpression of CXCL1 can effectively reduce the inhabitory rate of HCC cells induced by the ER stress.

DMRT, a gene family related to sexual determination, encodes a large group of transcription factors (DMRTs) with the double-sex and mab-3 (DM) domain (except for DMRT8), which is able to bind to and regulate DNAs. Current studies have shown that the DMRT gene family plays a critical role in the development of sexual organs (such as gender differentiation, gonadal development, germ cell development, etc.) as well as extrasexual organs (such as musculocartilage development, nervous system development, etc.). Additionally, it has been suggested that DMRTs may be involved in the cancer development and progression (such as prostate cancer, breast cancer, lung cancer, etc.). This review summarizes the research progress about the mammalian DMRTs' structure, function and its critical role in cancer development, progression and therapy (mainly in human and mice), which suggests that DMRT gene could be a candidate gene in the study of tumor formation and therapeutic strategy.
Male ; Animals ; Humans ; Mice ; Transcription Factors/genetics* ; Mammals/metabolism* ; Cell Differentiation ; Neoplasms/genetics*