2000年 · 第113卷第09期

Objective To examine the role of selenium(Se)in the expression and activity of selenium-dependent cellular glutathione peroxidase(GPX-1). Methods 46 patients with atrial septal defect or ventricular septal defect were separated into two groups, a control group(23 cases)and a Se supplementation group(23 cases). The Se supplementation group received 400 μg selenium per day for 7 days before surgery. We used biochemical techniques, atomic absorption, RT-PCR and cDNA sequence testing methods to evaluate and compare the changes during ischemia/reperfussion(I/R)in myocardial melondialdehyde(MDA)level, GPX activity and gene expression level, GPX cDNA nucleotide sequence, selenium and calcium and magnesium concentration. Results Before ischemia, taking selenium for 7 days did not change the selenium concentration in either plasma or blood cells in either group. The GPX mean activity level in the selenium group was slightly lower than that in the control group, and the MDA level was equal in both. After 30 minutes of reperfusion, the Se level in plasma and blood cells remained constant, while the myocardial Se concentration and GPX gene expression in the Se group increased significantly. The MDA level in the Se group reduced 4.2%, compared to an 8.2% rise in the control group. The mean level of GPX activity in the Se group was slightly lower than that in the control group. Both pre-and post-myocardial reperfusion, the Se group had a higher rate of myocardial GPX gene expression, and the nucleotide sequence was normal. These results indicate that supplementing Se is not likely to enhance myocardial GPX activity, but it could increase the GPX gene expression level, and thereby enhance the Se patients' myocardial antioxidant level during I/R, allowing free radicals to be scavenged as soon as they are generated. Conclusion Se supplementation could increase myocardial selenium content and improve GPX gene expression during I/R, and in this way defend against free radical peroxide damage to the myocardium. Chin Med J 2000; 113(9): 771-775

Objective To identify the role of cytokines involved in the development of lung fibrosis in patients with idiopathic pulmonary fibrosis(IPF). Methods Proteins and gene expression of platelet-derived growth factor(PDGF)-A and-B, insulin-like growth factor 1(IGF-1), and transforming growth factor beta(TGF-β)were measured in alveolar macrophages and open lung biopsies from patients with IPF using immunohistochemistry(IHC)and in situ hybridization(ISH). Results In specimens of bronchoalveolar lavage fluid(BALF), PDGF-A, PDGF-B, IGF-1, TGF-β were localized in alveolar macrophages. Evaluation of open lung biopsies from patients with IPF showed that IGF-1 was prominently present in pulmonary vessel walls in fibrotic lesions. PDGF and TGF-β proteins were localized to hyperplastic bronchio-alveolar epithelial cells, alveolar macrophages, fibroblasts, vascular smooth muscle and endothelial cells. Our in situ hybridization results were consistent with that of immunohistochemistry except that PDGF-A and TGF-β mRNA transcripts were not detected in bronchoalveolar epithelial cells. Conclusion These observations suggest that(1)alveolar macrophages play key roles not only in inflammation but also in the fibrotic process by releasing PDGF, IGF-1 and TGF-β;(2)IGF-1 could be responsible for angiogenesis in IPF;(3)PDGF, TGF-β are associated with fibroplasia and the deposition of extracellular matrix, as well as vessel remodeling and epithelial cell repopularization. Chin Med J 2000; 113(9): 776-782

Objective To investigate the significance and regulatory mechanism of eosinophil apoptosis in asthmatic airway inflammation using an animal models, as well as its relationship to IL-5 and IL-10. Methods An animal model of asthma was established by ovalbumin(OVA)sensitizing-challenging BALB/C mice. At seven points in the time course after challenge, bronchoalveolar lavage(BAL)was performed to obtain BAL cells. Levels of two Th2 cytokines, IL-5 and IL-10 were detected by ELISA. A double label technique combining CD15 with CD49d was used to distinguish eosinophils from other cell types. Cell apoptosis was assayed by PI stain using a flow cytometer. Results Eosinophil apoptosis was identified and a two-phase elevation of apoptosis percentages was observed, although no significant difference was found between average apoptosis in the asthmatic group and that in the control. Analysis of kinetic changes of eosinophil apoptosis and cytokine levels revealed a negative correlation between apoptosis percentages and levels of IL-5, and a closer correlation between apoptosis percentages and the IL-5/IL-10 ratio. Dexamethasone pretreatment markedly reduced IL-5 levels in BAL, elevated eosinophil apoptosis percentages, but had no effect on IL-10 levels. Conclusion Eosinophils underwent apoptosis in asthmatic airways. Equilibrium between IL-5 and IL-10 not only regulated eosinophil infiltration, but also modulated cell apoptosis. Chin Med J 2000; 113(9): 783-786

Objective Polymorphyism in vitamin D receptor(VDR)gene has been reported to play a major role in variations for genetic regulation of bone mass. Its role within various ethnic populations is not clear. The purpose of this study was to determine the frequencies of VDR genotypes in the Han and Uygur nationalities in China. Methods We analyzed the polymorphism of Bsm I restriction enzyme by PCR-RFLP technique in 162 healthy postmenopausal women of the Han nationality and 50 healthy postmenopausal women of the Uygur nationality in China. The genotype frequencies of VDR were calculated using Hardy-Weinberg equilibrium formula. Results In the Han nationality, the bb, Bb, and BB genotype accounted for 91.36%, 8.64% and 0%, respectively. In the Uygur nationality, frequencies were 74.00%, 18.00% and 8.00%, respectively. Conclusion There was a significant difference between the Han and Uygur nationalities in the frequency distribution of VDR genotype(P< 0.01). Compared with the Caucasian population in the United States, Australia and France, there was a similar value to Uygur nationality in the BB genotype. This investigation gave us further evidence on the different etiopathology of osteoporosis in various ethnic groups. Chin Med J 2000; 113(9): 787-789

Objective To explore the effect of anti-P-selectin monoclonal antibody(mAb)on renal ischemia/reperfusion(I/R)injury in rats. Methods Renal function, renal histopathological changes, plasma P-selectin levels and renal P-selectin protein and mRNA expression were studied in a renal I/R injury rat models. Biochemical measurement, ELISA, Immunohistochemistry and Nested RT-PCR were used. Results Renal function insufficiency and renal histopathological damage were much less in the anti-P-selectin mAb-treated group than the saline-treated group. Plasma P-selectin levels were lower and renal P-selectin protein and mRNA expression were down-regulated in the former group. Conclusion Anti-P-selectin mAb might be an efficient approach for the treatment of renal I/R injury. Chin Med J 2000; 113(9): 790-793

Objective To confirm and compare the therapeutic efficacies and remote effects of a Chinese type A botulinum toxin(CBTX-A, Lanzhou Biological Products Institute, China)and Botox(Allergan Inc., USA)for focal dystonia and muscle spasm. Methods Prospective open study was conducted over 4 years for focal dystonia and muscle spasm. We enrolled 785 patients: 192 were injected with Botox and 593 with CBTX-A. They were followed for 3 to 48 months. Meanwhile single fiber electromyography(SFEMG)was performed in a subset of 40 patients before, 2-3 weeks, 5-8 weeks and 4-5 months after injection of Botox or CBTX-A. Results There were no significant differences in clinical effects from two preparations, including the latency of response, maximal benefit and duration of improvement. The dose of the Chinese preparation which produced effects similar to Botox was higher. A significant increase in jitter was demonstrated 2-3 weeks after injection in both groups and fiber density values increased at the same time or later and remained 4-5 months after injections. Conclusion Both preparation are safe and effective treatments for patients with focal dystonia and muscle spasm. They both have subclinical effects on neuromuscular transmission of remote uninjected muscles. The Chinese preparation is a little less powerful but much cheaper than Botox. Chin Med J 2000; 113(9): 794-798

Objective To assess the incidence of multiple primary malignancies combined with lung and other organs. Methods All patients who were consecutively treated for lung cancer from December 1964 to December 1992 were retrospectively analyzed regarding the occurrence of simultaneous primary tumor elsewhere in the body. Results Of 1019 patients reviewed, 21(2.1%)had associated carcinoma of other organs. In these 21 patients, the incidence of associated aerodigestive tract cancer was 71 % and cancer of other organs was 29%. Five patients had simultaneous cancer with the lung cancer and 16 metachronous lung cancer associated with cancer of other organs. Conclusions Multiple primary tumors in patients with carcinoma of the lung is not a rare phenomenon. Surveillance programs for detection of second primary tumors should focus on this group of patients. Surgeons should be aware of the possibility of double cancer, and the patient's condition and stage of the carcinoma must be taken into consideration in the determination of operative indications and method. Chin Med J 2000; 113(9): 799-801

Objective To investigate the expression and clinical significance of urokinase type plasminogen activator(uPA)in human gliomas. Methods mRNA and protein expressions of uPA were examined by Northern blot hybridization and immunohistochemical method in 43 cases of gliomas and 5 cases of normal brain tissues and their relationship to clinical indexes was comprehensively analyzed. Results All tissues expressed the 2.5 kb transcript of uPA mRNA. The uPA mRNA level in high-grade gliomas was considerably higher than that in low-grade gliomas and normal brain tissues(P < 0.01). Levels of uPA mRNA expression in tumor tissues with recurrence during 18 postoperative months and a survival period less than 3 years, were significantly higher than counterparts(P< 0.01). uPA mRNA expression was strongly correlated with the microvessel quantity(MVQ)in gliomas(r=0.56, P<0.01). uPA protein was mainly distributed in tumor cells and endothelial cells of glioblastomas and anaplastic astrocytomas. Conclusion Expression of uPA is associated with the malignant progression, invasion and angiogenesis of gliomas, and it may play a critical role in the recurrence and prognosis of gliomas. Chin Med J 2000; 113(9): 802-804

Objective To study the influence of a stress-relaxation plate on the remodeling of callus and cortex under the plate. Methods The bilateral tibia diaphysis of New Zealand rabbit were osteotomized and fixed with stress-relaxation plate(SRP)and rigid plate(RP), respectively. Polarized light microscopy and transmission electron microscopy(TEM)were used to study the remodeling of callus and the cortex under the plate from 4 to 24 weeks postoperatively. Results Polarized light microscopy: the structural changes of callus and cortex beneath the plate are similar in the SRP and RP groups at the early postoperative stage, manifesting an alignment disorder of collagen fibers with a weak birefringence in the callus and absorption cavities in the cortex under the plate. After the twelveth postoperative week, the SRP group showed callus starting to transform to lamellar bone and absorption cavities in the cortex under the plate becaming smaller. By contrast in the RP group the absorption cavities in the callus and cortex under the plate became larger and the whole layer of cortex was cancellated. TEM: the active osteoclasts appeared in both SRP and RP groups in the period from 4 to 8 weeks postoperatively. In the SRP group, many functionally active osteoblasts could be seen on the surface of the bone, while in the RP group, the osteoblasts were not very active. By 24 weeks postoperatively, the shape of osteocytes were normal but the number of the osteoclasts were small in the SRP group. In the RP group, the osteoclasts became more active and osteocytic osteolysis was manifested. Conclusions Fixation with SRP not only enhanced callus remodeling, but also abated the degree of osteoporosis in the cortex under the plate. This approach may lead to an improved osteosynthetic apparatus. Chin Med J 2000; 113(9): 805-809

Objective To compare the surgical managements for ectopic pregnancy. Methods In a retrospective analysis, we examined the trend of surgical procedures and the results of different management in 149 patients. Results The change from laparotomy to laparoscopic treatment was significant. The success rates of salpingostomy and salpingectomy under laparoscopy or laparotomy were 100%. No serious complications occurred. The operation time and length of hospital stay for laparoscopic salpingostomy were shorter than those for laparotomy with salpingostomy. Conclusion Laparoscopic salpingostomy and laparoscopic salpingectomy are better than laparotomy in the treatment of ectopic pregnancy. Chin Med J 2000; 113(9): 810-812