2002年 · 第115卷第06期

Objective To observe the biological changes of primary human nasopharyngeal epithelial cells in the early stage of immortalization. Methods The morphological changes of nasopharyngeal epithelial cells were observed by phase-contrast microscopy, and the activity profile of senescence-associated β-galactosidase (SA-β-Gal) was detected by SA-β-Gal staining. The expression of p16INK4a protein was tested by immunochemical assay, and the life span in vitro of nasopharyngeal epithelial cells was calculated as population doublings. In addition, the expression of Epstein-Barr (EB) virus latent membrane protein 1 (LMP1) was also detected by immunofluorescence staining. Results Morphologically, cells treated with EB virus and 12-o-tetradecanoyl-phorbol-13-acetate (TPA)formed multi-layer foci, and their cellular life span in vitro was extended (about 155 days of culture). A low percentage of cells (about 4.8%) expressed SA-β-Gal activity at late primary culture, and did not always express p16INK4a protein in the progression of culture. Conclusions Nasopharyngeal epithelial cells treated with EB virus in cooperation with TPA can pass through the stage of senescence and enter the early stage of immortalization. Some changes of phenotype occur in these cells. Our results provide data for further studying the mechanism of immortalization and the establishment of a human nasopharyngeal epithelial cell line. Chin Med J 2002; 115(6): 803-809

Objective To investigate the role of retinoic acid receptor β (RARβ) in mediating inhibitory effect of alltrans retinoic acid (ATRA) on activator protein-1 (AP-1) activity in gastric cancer cells. Methods Transient transfection and chloramphenicol acetyltransferase (CAT) assay, Northern blot, gene transfection, 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay, and anchorage-independent growth assay were used. Results Transient transfection of RARβ expression vector into MKN-45 cells resulted in the RARβ concentration-dependent repression of AP-1 activity induced by 12-o-tetradecanoylphorbol-13-acetate(TPA), regardless of the presence of ATRA. When the c-jun and c-fos expression vectors were cotransfected with the RARβ expression vector into MKN-45 cells, AP-1 activity was also obviously repressed. The inhibitory effect, again, was RARβ-concentration-dependent. The stable transfection of the RARβ gene into MKN-45 cells led to cell growth inhibition and colony formation inhibition by ATRA. Furthermore, Cotransfection of both RARβ/DNA binding domain (DBD) and reporter gene could not alter AP-1 activity, even in the presence of ATRA. However, when the cotransfection was substituted with the RARβ/ligand binding domain (LBD), the inhibition was significantly enhanced by ATRA. Conclusion RARβ might be required for anti-AP-1 activity, and contribute to growth inhibition of gastric cancer cells by ATRA. Chin Med J 2002; 115(6): 810-814

Objective To evaluate the etiology of Shiga-like toxin-producing Escherichia coli (SLTEC) in children with diarrhea. Methods We designed and synthesized 3 pairs of primers located in the SLT1, SLT2, and eaeA genes of enterohaemorrhagic Escherichia coli (EHEC), while the virulent genes SLT1, SLT2, and eaeA from E. coli species were amplified by polymerase chain reaction (PGR). Results One strain of EHEC with SLT1, SLT2, and eaeA in 29 reference strains of diarrhea-causing E. coli (DCEC) and 10 strains of other enterobacteria detected by PGR had positive reactions, while all other DCEC and enterobacteria were negative. Of 474 strains of E. coli isolated from 1032 children with diarrhea and detected by PCR, 20 strains of SLT1 producing E. coli (4.2%) positive, and 7 strains of SLT2 producing E. coli (1.5%) positive; while of 74 strains of entero-SLTs-producing and invasive Escherichia coli (ESIEC), 15 strains of SLT1 (20.3%) and 5 strains of SLT2 (6.8%) were positive. Conclusion Shiga-like toxin E. coli has been identified as a major etiologic agent of children with diarrhea in Taiyuan, China. Chin Med J 2002; 115(6): 815-818

Objectives To determine the relative densities of the GABAergic subpopulation defined by calcium-binding proteins and to further study the importance of changes in GABAergic interneurons on neuropathology in the hippocampus in schizophrenia cases. Methods The relative densities and neuronal body size of cells immunoreactive for the calcium-binding proteins parvalbumin and calretinin as well as the area size of the hippocampal sub-fields were determined from the hippocampal tissue sections taken from schizophrenic patients and well-matched control subjects(15 per group). Results No significant difference in the density of calretinin-immunoreactive neurons and the neuronal body size of calretinin-positive neurons was found between subject groups. Relative to normal controls,schizophrenic patients showed a significant and profound deficit in the relative densities of parvalbumin-immunoreactive neurons in all hippocampal sub-fields. These reductions were more apparent in male schizophrenic patients and were unrelated to antipsychotic drug treatment, age or duration of illness. Conclusion The findings provide further evidence to support a profound and selective abnormality of a sub-population of GABAergic neurons in the hippocampus in schizophrenia cases, and are consistent with the etiological hypothesis of the neurodevelopment of schizophrenia. Chin Med J 2002; 115(6): 819-823

Objective A certain fraction of patients failed palliative treatment of 153Sm-ethylenediaminetetramethy lenephosphate (153Sm-EDTMP) for painful skeletal metastases were reviewd. A comparative analysis was designed to identify the factors related to therapeutic response. Methods From a 3-year multi-center clinical trial, 51 cases were collected who did not respond to an intravenous injection of 153Sm-EDTMP at a dosage of 0.5 - 1.5 mCi/kg. The therapeutic efficacy was evaluated via changes of symptoms, general condition, consumption of analgesics, sum of effect product,and Karnofsky scores. The age, sex, history of treatment, tumor type, location of bony involvement,uptake ratio and number of metastases, and doses used by the patients were compared to those of the responders. Results In 51 non-responders, 43 were male, 34 suffered from lung cancer, 41 had bone lesions in the vertebrae, 39 in the pelvis, and 24 had metastases in the lower extremities. Sex distribution, tumor type and location of the lesion differed significantly between responders and non-responders. No other factor showed differences between the two groups. Though patients of younger age, and lesions with lower uptake of radiopharmaceutical seemed to fail the treatment more easily as observed clinically, this was not confirmed by statistical analysis. Conclusion The sex of the patients, certain types of primary tumors and metastases to lower parts of the body were found to influence the patients' response to a single dose of 153Sm-EDTMP palliation. Further exploration of a better way to determine dosage and predict response for each individual case is needed . Chin Med J 2002; 115(6): 824-828

Objective To detect mutations of the retinitis pigmentosa GTPase regulator (RPGR) gene in two Chinese X-linked retinitis pigmentosa families. Methods Fragments of exons 1 - 19 of the RPGR gene were amplified with intronic primers, using genomic DNA as template. The polymerase chain reaction (PCR) products were analysed by single-strand conformation polymorphism (SSCP) and direct sequencing. Mutations were identified by comparing DNA sequences of the patients with those of the normal controls. Results Two novel mutations, c1536delC and E332X, were identified in exons 12 and 9 of the RPGR gene in both families. Each mutation was the first mutation found in their respective exons. Both mutations were predicted to cause premature termination, which resulted in truncated proteins without normal functions of the RPGR products. Conclusions Both mutations are the genetic basis of the pathogenesis in the respective families. Our data might be helpful in analysing the function of the RPGR protein. Chin Med J 2002; 115(6): 833-836

Objectives To assess the relationship between myocardial regional perfusion using second harmonic myocardial contrast echocardiography (MCE) by venous injection of Levovist and coronary artery stenosis detected by coronary angiography to determine whether MCE can be used to detect coronary artery disease(CAD) and its sensitivity and specificity for detecting CAD. Methods Thirty-six patients who underwent coronary artery angiography and MCE formed the study groups. Ten myocardial segments (5 each in the apical two- and four-chamber views) from the images were scored for detecting myocardial perfusion as follows: 1, normal perfusion; 2, decreased perfusion;and 3, perfusion defect. The arteries were classified as normal or diseased. The diseased arteries were classified into three groups according to the perfusion scores. Results There were significant differences in coronary diameter stenosis among the different perfusion score groups (P <0.001) . There were 10 total occluded arteries, and the myocardial perfusion scores were different because of different collateral circulation. In the normal perfusion group (Group A), the coronary diameter stenosis was 65% ± 12%, and the myocardial perfusion score index was 1 ± 0.00. In the decreased perfusion group (Group B), the average coronary diameter stenosis was 82% ± 8%, and the myocardial perfusion score was 1.93± 0.16. The diameter stenosis was less than 85%in 63 %of the coronary arteries (including diameter stenosis ≤75%in 12%of the vessels). The diameter stenosis was 85%- 90%in 22%of the coronary arteries and > 90%in 15%of the arteries. In the perfusion defect group (Group C), the average diameter stenosis was 90% ± 6%, and the myocardial perfusion score index was 2.89 ± 0.24. The diameter stenosis was ≥ 85% in 94% of the coronary arteries, and the diameter stenosis was <85%and > 75%only in 6%of the coronary arteries. The overall sensitivity and specificity of MCE in identifying angiographic coronary diameter stenosis was 67%and 100%, respectively. The false negative rate was 32.6%for the 108 coronary arteries. Further subdivided analysis showed the sensitivities in Groups A, B and C were 0, 100%, and 100%, respectively. The sensitivity increased with increased lumen diameter stenosis of coronary arteries. Conclusions There is a close relationship between coronary artery stenosis and MCE perfusion scores. MCE with venous injection of new generation contrast can define the presence of CAD and lesion graded classifications. Some disagreements between perfusion score and coronary diameter of stenosis may indicate other factors such as different collateral circulation, which should be further investigated. As artery stenosis increases, the sensitivity of MCE is increased. Chin Med J 2002; 115(6): 837-841

Objective To evaluate the effect of a system of velopharyngeal incompetence (VPI) management after the application of obturator. Methods Using nasopharyngofiberoscope (NPF) and a computer analysis system, we quantitatively analyzed the improved state of velopharyngeal incompetence in 100 patients with unilateral and/or bilateral cleft palate. Results The velopharyngeal closure (VPC) can be greatly improved by using a temporary oral prosthesis(obturator) and speech training. An objective quantitative standard was established to evaluate the change of velopharyngeal closure of cleft palate patients after surgery and conservative treatment. Conclusions The method used is more succinct, accurate and practical than previous methods. In order to reflect the state of velopharyngeal incompetence, the concept of improvement rate of velopharyngeal incompetence (IRVPI) is put forward. Chin Med J 2002; 115(6): 842-845

Objective To determine the in vitro expression of interleukin-12 (IL-12) and its effect on signal transducers and activators of transcription (STAT) signaling molecules in peripheral blood mononuclear cells(PBMCs) in patients with systemic lupus erythematosus (SLE). Methods Peripheral blood mononuclear cells in 39 patients with definite systemic lupus erythematosus and 11 healthy volunteers were collected. Expression of IL-12 P40mRNA in PBMCs was determined with reverse transcription-polymerase chain reaction (RT-PCR). Quantity of IL-12 protein supernatant was measured by enzyme-linked immunosorbent assay (ELISA) . The levels of phosphorylated STAT3 and STAT4 signaling molecules in PBMCs were detected by immunoblot. Results Levels of IL-12 protein and mRNA expression in patients with active or inactive SLE were significantly higher than those in controls. Phytohemagglutinin (PHA) may promote the expression of IL-12. IL-12 alone induced the phosphorylation of STAT3 and STAT4 in PBMCs from patients with SLE, especially in active SLE. However it had no obvious effect on normal PBMCs. Phosphorylated STAT3 and STAT4 might be observed in normal PBMCs treated with IL-12 plus PHA. Conclusion IL-12 is produced aberrantly in patients with SLE. IL-12 might exert its biological role in SLE via the aberrantly phosphorylated STAT3 and STAT4 signaling molecules. Chin Med J 2002; 115(6): 846-850

Objectives To explore the pathogenesis of rheumatoid arthritis (RA) by studying the expression of T cell receptors (TCRs). Methods T cell receptor vβ (TCR vβ) gene usage and expression were analyzed from synovial membrane and peripheral blood of 8 RA patients, 2 osteoarthritis patients and 2 accident amputees. The complementary determining region 3 (CDR3) of 25 TCR Vβ subfamily genes in unselected T cell populations were amplified semi-quantitatively by reverse transcription-polymerase chain reaction(RT-PCR). The products were further studied by genescan for frequency of vβ usage. Results The numbers of vβ subfamilies expressed by T cells from RA peripheral blood and synovial membrane were not significantly restricted. More importantly, biased vβ gene expression in RA synovium was observed and Vβ6, Vβ17, and Vβ22 genes were the predominant subfamilies. It was noteworthy that the expression of Vβ17 in RA synovium was significantly increased. Conclusion Our data were consistent with the hypothesis that several antigen or superantigen-driven processes may be involved in the pathogenesis of RA. Chin Med J 2002; 115(6): 856-859