2002年 · 第115卷第09期

Objective To investigate the different effects of an angiotensin Ⅱ type 1 (AT1) receptor antagonist,losartan, and an angiotensin converting enzyme (ACE) inhibitor, fosinopril, on cardiomyocyte apoptosis,myocardial fibrosis, and angiotensin Ⅱ (Ang Ⅱ) in the left ventricle of spontaneously hypertensive rats(SHRs). Methods SHRs of 16-week-old were randomly divided into 3 groups: SHR-L (treated with losartan,30 mg·kg -1·d-1), SHR-F (treated with fosinopril, 10mg · kg-1 • d-1), and SHR-C (treated with placebo). Each group consisted of 10 rats. Five rats, randomly selected from each group, were killed at the 8th and 16th week after treatment. Cardiomyocyte apoptosis, collagen volume fraction (CVF), perivascular collagen area (PVCA) and Ang Ⅱ concentrations of plasma and myocardium were examined. Results Compared with the controls at the 8th and 16th week, systolic blood pressures were similarly decreased in both treatment groups. Left ventricular weight and left ventricular mass indexes were significantly lower in both treatment groups. However, the latter parameter at the 16th week was reduced to a less extent in the fosinopril group than that in the losartan group. Compared with the controls,cardiomycyte apoptotic index was significantly reduced at the 8th week only in the fosinopril group, and at the 16th week in both treatment groups. The index of the fosinopril group was lower than that of the losartan group at the latter endpoint examined. Compared with the controls, the left ventricular collagen volume fraction and perivascular collagen area at the 8th and 16th weeks were significantly reduced in the SHRs treated with either fosinopril or losartan. However, the collagen volume fraction at the latter endpoint in the fosinopril group was lower than that in the losartan group. Compared with the controls at endpoints, plasma and myocardium Ang Ⅱ levels were significantly increased in the losartan group. However, plasma Ang Ⅱconcentrations were not altered, and myocardium Ang Ⅱ concentrations at the 8th and 16th weeks were significantly reduced in the fosinopril group. Conclusions Both losartan and fosinopril could effectively inhibit cardiomyocyte apoptosis and myocardial fibrosis and reverse heart hypertrophy. Fosinopril may be more effective in these cardioprotective effects,suggesting that the effects of both drugs are related to the inhibition of myocardium renin-angiotension-aldsterone system. Chin Med J 2002; 115(9): 1287-1291

Objective To investigate differences between hepatic and biliary lipid metabolism and secretion of genetically gallstone-susceptible (C57L) and resistant (AKR) mice and the mechanism of cholesterol gallstone formation. Methods The inbred C57L and AKR mice were fed a lithogenic diet containing 15%fat, 1.25%cholesterol and 0.5%cholic acid for four weeks. Hepatic cholesterol content and secretion rates of biliary lipids, as well as phenotypes of the liver and gallbladder were determined and examined before and after the feeding of the lithogenic diet. Results Both before and after ingestion of the lithogenic diet, hepatic secretion rates of all biliary lipids in C57L mice were markedly higher than that of AKR mice (P <0.05, P <0.01, respectively), whereas hepatic cholesterol contents of C57L mice were significantly lower than that of AKR mice (P <0.05). Furthermore, after consumption of the lithogenic diet, the increase in hepatic secretion rate of biliary cholesterol in C57L mice was significantly higher than that in AKR mice (P <0.01). Cholesterol gallstones formed in C57L mice and fatty livers developed in AKR mice. Conclusions Biliary cholesterol hypersecretion is the key pathophysiological defect of gallstone formation,lith genes have effects on biliary cholesterol hypersecretion and susceptibility to cholesterol gallstone formation in C57L mice. Lithogenic bile is formed at the canalicular membrane and precedes the development of cholesterol gallstones. It is most likely that cholesterol and bile acid hyposecretion make the AKR strain susceptible to the development of fatty livers and resistant to gallstone formation. Chin Med J 2002; 115(9): 1292-1295

Objective To establish a serum-free culture system of dendritic cells (DCs) from chronic myeloid leukemia(CML) cells so that DCs vaccine may be applied to the adoptive immunotherapy of CML in the near future. Methods Fetal calf serum, serum-free medium and autologous serum were used for culture of DCs. The usage of cytokines was classified into two groups: group A (stem cell factor, granulocyte/macrophage colony-stimulating-factor, tumor necrosis factor-α and interleukin-4) and group B (granulocyte/macrophage colony-stimulating-factor, tumor necrosis factor-a and interleukin-4). The phenotypes of DCs were analyzed by using indirect immunofluorescence and flow cytometry. Mixed leukocyte responses were performed by methyl thiazolyl tetrazolium (MTT) assay. Chromosome analysis of DCs can be achieved by displaying G banding. T cells from CML patients were stimulated with autologous DCs and T-cell cytotoxicity was measured by (MTT) assay. Results CD34+ cells or mononuclear cells were obtained from peripheral blood or bone marrow samples of eight patients of chronic-phase CML. Group A of serum-free medium was better than group B in expansion of total cell numbers and the rate of DCs. These results of serum-free medium were not significantly different from those of fetal calf serum medium, but the results of autologous serum medium were inferior to two groups above. The expression of major histocompatibility complex class Ⅱ antigen on the surface of DCs was notable (> 50%), but the expression of CD83 and the costimulatory molecules CD86 was not noticeable (10%- 50%). Although CD1 a+/CD14- DCs were potent stimulators of allogeneic lymphocytes, expansion of T cells from normal volunteers were not significant (average 27.2 fold at DCs: T cells ratio of 1:10). At day 12, CD1a+ cells from three patients were studied by displaying G banding and Ph+ cells in these populations were 100%, 98% and 60%, respectively. At an effector: target ratio of 40:1, 32% to 45%cytotoxicity was noted with DC-stimulated T cells against autologous leukemia cells. Conclusions A stable serum-free culture system of CML-DCs was established. The expression of CD83 and CD86 on the surface of CML-DCs and DCs' potent stimulation of allogeneic lymphocytes were not notable. DCs in CML patients can be derived from the malignant clone and these malignant DCs could induce anti-leukemic reactivity in autologous T lymphocytes without the necessity for additional exogenous antigens. Chin Med J 2002; 115(9): 1296-1300

Objective To study glomerular expression of C-C chemokines, monocyte chemoattractant protein-1(MCP-1), macrophage inflammatory protein-1α and β (MIP-1α, MIP-1β) and the effect of steroid and cyclophosphamide (CTX) intermittent intravenous pulse therapy on expression in patients with crescentic glomerulonephritis (CGN) to further investigate the underlying mechanism of the treatment. Methods Twelve patients with initial biopsy-proven CGN2, 6 with lupus nephritis (lupus-CGN, LN-CGN)and 6 with vasculitis, (vasculitis-CGN, V-CGN) were enrolled in this study. They underwent an initial biopsy before steroid and CTX intermittent intravenous pulse therapy and were biopsied again one to three months later. Expression of MCP-1, MIP-1α, MIP-1βp, and CD68 in glomeruli with cellular and fibrocellular crescents were examined by immunohistochemical analysis in serial sections of renal biopsies. The effect of the pulse therapy on histopathological changes was also observed. Results Although steroid and CTX intermittent intravenous pulse therapy markedly reduced the degree of glomerular crescent formation both in LN-CGN and V-CGN, the effect of the therapy on glomerular chemokine expression was significantly different between LN-CGN and V-CGN. It was found that steroid and CTX intermittent intravenous pulse therapy reduced the expression of CD68, MCP-1, and MIP-1α, but had no effect on MIP-1β in glomeruli with cellular crescents of patients with LN-CGN. In patients with V-CGN, the therapy also reduced the expression of CD68, but had no effect on MCP-1, MIP-1α, and MIP-1β in glomeruli with cellular crescents. It was noted that the degree of glomerulosclerosis and tubular interstitial fibrosis increased more significantly at the second biopsy in V-CGN as compared to LN-CGN. Conclusions The efficacy of steroid and CTX intermittent intravenous pulse therapy in CGN might be affected by reduction of glomerular chemokine expression. The different changes in glomerular expression of MCP-1 and MIP-1α in patients with LN-CGN and V-CGN after pulse therapy may correlate to different responses to treatment and prognosis. Chin Med J 2002; 115(9): 1301-1307

Objective To determine the relationships of Met416Val and Xbal polymorphism of muscle glycogen synthase (GYS1) gene and Trg64Arg variant of the β3-adrenergic-receptor (β3-AR) gene with type 2 diabetes mellitus (DM) and its intermediate phenotypes in the Chinese population. Methods Polymerase chain reaction-oligonucleotide ligation assay and restriction fragment length polymorphism assay were used to evaluate the GYS1 and β3-AR gene polymorphisms in 102 pairs of case-control Chinese spouses. Results Subjects with Met416Val variant had a significantly higher 2-hour post-glucose level than subjects without this variant had in diabetic group (P=0.032). The Met416Val polymorphism of GYS1 gene was not significantly associated with the risk of type 2 DM (adjusted OR=1 . 67; 95%CI: 0 . 73 - 3 . 81, P= 0.223). Subjects with Trp64Arg variant had a significantly higher serum uric acid level than subjects without this variant had in diabetic group (P=0.034). The combination of BMI and Arg64 allele carrier of the β3-AR gene increased the diabetic risk over four-fold (adjusted OR=4.00; 95%CI: 1.53 - 10.45, P= 0.005). Conclusions In the Chinese population, Met416Val polymorphism is identified in a subgroup of diabetic subjects with high 2-hour post-glucose. It will explain why some diabetic patients appear to be genetically predisposed to developing high postpradial glucose level. The presence of the Arg64 allele in the β3-AR gene may predispose patients to higher serum uric acid level. Chin Med J 2002; 115(9): 1308-1311

Objective To improve the clinician's awareness of angiostrongyliasis. Methods The clinical and laboratory data as well as the epidemiological information concerning 18 patients with eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis were analyzed. Results All patients had a history of eating raw fresh water snail (Ampularium canaliculatus) before the onset of the disease. Incubation period ranged from 1 to 25 days. The major symptoms of the patients had severe headache and pain in the trunk and limbs. Increased eosinophlic count in peripheral blood and cerebrospinal fluid was noted. Tested by enzyme-linked immunoadsorbent assay (ELISA), sera were specifically IgG-antibody positive against Angiostrougylus cantonensis antigen, but were negative against other parasitic antigens such as Paragonimus westermani, Cysticerus, Cellulosae hominis, Echinococcus granulosus and Trichinella spiralis. Abnormal spotty signals were found in 2 cases with brain magnetic resonance imaging. Electroencephalogram (EEG) showed slow alpha rhythm. All the patients were effectively treated with combined administration of albendazole and dexamethazone. Conclusions Angiostrongyliasis is one of the common causes leading to eosinophilic meningoencephalitis. To our knowledge, Wenzhou is the first small outbreak site of angiostrongyliasis discovered in Chinese mainland. Chin Med J 2002; 115(9): 1312-1315

Objective To study the effect of Ginkgo biloba extract on rats during ischemia/reperfusion and its influence on intracellular calcium in hippocampal neurons. Methods Model of intraluminal occlusion of the middle cerebral artery (MCAO) was used to prepare the ischemia/reperfusion cortex tissue. Concentration of MDA was determined by measuring thiobarbituric acid-reactive substance. GSH-PX was quantified using the thiobarbituric acid (TBA) technique. SOD was assayed througha xanthine method. Endogenous amino acids were quantified by high performance liquid chromatographic (HPLC) analysis. Primary culturs of hippocampal neurons were prepared for a free intracellular calcium ([Ca2+]I) assay by Fura-2 based single cell microfluoremetric technique. Results Comparing control and treatment groups, the concentration of SOD and GSH-PX were higher,whereas that of MDA was much lower; the concentration of glutamate and aspartate decreased and that of GABA increased markedly at all time point (P <0.01), Gly also decreased at some time points(P <0.05). The differences were significant between the groups of 10 mg/kg, 15 mg/kg and the groups of 5 mg/kg. When 1 x 10-5 mol/L glutamate was applied with 25 μg/ml ginkgo biloba extract to cultured neurons, the increase in [Ca2+]I was lower than that caused by applying glutamate alone. Its peak value was much lower and increased phase was longer, its declining phase was shorter. After returning to baseline, the application of 1 x 10-5 mol/L glutamate could induce the reaction to recover. Conclusions Ginkgo biloba extract could protect damaged neurons by keeping the balance of inhibitory/excitatory aminoacids, enhancing the free radical scavengers system, and inhibiting the effect of glutamate on [Ca2+]I. Chin Med J 2002; 115(9): 1316-1320

Objective To study cognitive function and cerebral metabolic changes in patients with transient global amnesia (TGA). Methods Three patients with TGA were given mini-mental state examination (MMSE), revised Wechsler memory scale (WMS-R) examination and magnetic resonance imaging (MRI) scans after they had been diagnosed as TGA. Using 18F labelled deoxyglucose as tracer, patients were given a positron emission tomography (PET) examination at different periods during recovery. Results No obvious abnormality was found in MMSE and MRI scans in the three patients. However,WMS-R examination and cerebral PET imaging displayed cognitive dysfunction of varying degrees and low metabolism in local areas related to memory in 2 of 3 patients. Conclusions In TGA patients, cognitive function and cerebral metabolic levels are closely correlated with duration of symptoms. It is necessary to stop the TGA attack as quickly as possible early time. Chin Med J 2002; 115(9): 1321-1323

Objective To study the character of mutants originating from Japanese encephalitis viruses and the relationship between the characterization of mutant strains and E protein expression . Methods Persistent infection was established with standard strains of Japanese encephalitis viruse,known as parental viruse, in a human hepatoma cell line, KN73. Cells were subcultured weekly using trypsinization techniques. Cell-associated viruses of persistently infected cells were collected by a freeze and thaw method. Virus titers were examined by plaque method using baby hamster kidney (BHK) cells. Indirect immunofluorescence assays were used to examine E and NS3 protein antigens. Western blot analysis was used to test expression of E and NS3 proteins. Results In the early phase (24-36 h) post-infection, virus titer in culture fluid from KN73 cells infected with parental viruses were 106 PFU/ml. They were 103-4 PFU/ml in the late phase (3 years) post-infection. The titer of cell-associated viruse was 102-3 PFU/ml. A virus super-infection assay found that virus titers in culture fluid from persistently infected KN73 cells acutely super- infected with parental viruses were much lower than that of culture fluids in acutely infected normal KN73 at the same phase. Indirect immunoflurescence assay revealed that the quantity of viral antigens in persistently infected KN73 cells was lower than that in acutely infected KN73 cells with parental viruses. Western blot analyses indicated that the molecular weights of E and NS3 proteins were 53 kD and 73 kD, respectively. Expression of NS3 protein in persistently infected KN73 cells was stable but expression of E protein was markedly suppressed. Conclusions The virulence and reproduction of viruses obtained from persistently infected KN73 cells,which have some features of Dl viruses and were involved in persistent infection, was lower than that of parental viruses. These mutants may have be related to the decrease in E protein expression. Chin Med J 2002; 115(9): 1324-1327

Objective To apply fractionated-clamping for repair of thoracoabdominal aortic aneurysm (TAA), and evaluate its effects in decreasing surgical mortality and severe complications, such as renal failure and paraplegia, a modified crawford procedure were prospectively evaluated. Methods Using modified shunting and cross-clamping techniques, modified Crawford repair in 13 thoracoabdominal aorta patients were performed in the Vascular Division at Peking Union Medical College Hospital. TAA Crawford classification: 1 type I, 2 type Ⅱ, 2 type Ⅲ and 3 type Ⅳ TAA. Debakey classification: 1 type I, 4 type Ⅲ (including 2 ruptured aneurysms), and 1 aortic coarctation. Results Thirteen procedures were performed successfully. One died of ventricular fibrillation just before completing the operation. Surgical mortality rate was 7.7%(1/13). Postoperative complications included 1 acute necrotic pancreatitis, 1 ARDS, 1 paraplegia, 1 acute renal failure, and 2 thoracic cavity bleeding. Total complication rate was 53.8%(7/13). Conclusions Fractionated-clamping in thoracoabdominal aortic aneurysm repair is our modified Crawford procedure and aortic bypass. Clinical results demonstrate that our procedure decreased surgical mortality and major complication rate, and also alleviated viscera ischemic injury. Fractionated-clamping in aorta replacement is a practical procedure for TAA repair under general anesthesia at normal temperature. Chin Med J 20021 115(9): 1328-1331

Objective To study the clinical and pathological characteristics of solitary fibrous tumor (SFT). Methods Clinical pathological analysis and immunohistochemical studies were performed on ten patients with SFT. Results The SFTs located variously and showed different histological features. All cases showed positive staining for CD34, VM (vimentin) and Bcl-2, but negative staining for Desmin, S-100, CK (cytokeratin)and EMA (epithelial membrane antigen). Conclusions SFT is described as a " patternless " growth pattern. According to clinical pathological features and immunohistochemistry, it is different from other soft tissue tumors. Long-term clinical follow-up is necessary for this kind of tumor. Chin Med J 2002; 115(9): 1412-1414

Objective To set up a rapid and simple method for identificating bacteria by 16S-23SrDNA intergenic spacer regions (ISRs). Methods Polymorphic products of PCR from ISRs were selected on agarose gel and sequenced directly using purified fragments by excising the gel without cloning. Nucleotide sequences were compared with GenBank databases and analyzed by DNAMAN program. Results There was only a single product in streptococcus genus after PCR amplification of 16S-23SrDNA ISRs. Five streptococcal species were obtained from 7 strains of streptococcus. Two major amplicons were consistently generated for 8 strains of Haemophilus influenzae (H. influenzae) . The sequence data showed that they all belonged to H. influenzae type b on GenBank databases. Conclusion PCR and direct sequencing of 16S-23SrDNA ISRs were very successful methods for bacterial species identification. Chin Med J 2002; 115(9): 1415-1417