2004年 · 第117卷第01期

Background Internal metallic stents have been widely used in clinical practice, but a high postoperative restenosis rate limits its application. The purpose of this study was to determine the effect of intrabiliary radiation on muscle formation and biliary duct remodeling after biliary duct balloon injury in dogs. Methods Twenty male dogs (15 -20 kg) were randomly divided into treatment group (n=10) and control group (n=10). Balloon overstretching injury was induced using a balloon catheter placed across the biliary duct. Subsequently, a 103Pd radioactive stent was positioned at the target site in each animal in the treatment group, providing the injured biliary duct with a radiation dose of 12. 58 x 107 Bq. Dogs in the control group received Ni-Ti stents. All the dogs were killed one month after initial injury. The injured sections were dissected free from the dogs, and were processed for histological and morphological study. Cross-sections were stained with hematoxylin-eosin, Masson's trichrome,and Verhoef-van Giesen. Muscle formation area and lumen area were determined using a computer-assisted image analysis system. Results Compared with the control group, 103Pd radioactive stents significantly reduced muscle formation area (78. 3%, P <0.01), and percentage area of stenosis [control stents: (60. 0 ±21. 6)%, 103Pd radioactive stents: (31. 6 ±9. 5)%]. In addition, in the treatment group, the biliary duct lumen area was significantly larger than that in the control group (P <0. 01). Conclusions 103Pd radioactive stents providing a radioactive dose of 12. 58 × 107 Bq are effective in reducing muscle formation and biliary duct remodeling after balloon overstretching injury. Chin Med J 2004; 117(1): 104-106

Background Nasopharyngeal carcinoma (NPC) shows highly invasive and metastatic features. This study aims to investigate macrophage migration inhibitory factor (MIF)-induced invasion of NPC cells in vitro and the effects on matrix metalloproteinases (MMPs) and interleukin-8 (IL-8), and to study the mechanism of tumor cell invasion and metastasis in the early stage of NPC. Methods Two nasopharyngeal carcinoma cell lines, CNE-1 and CNE-2, were adopted in this study. The NPC cell invasion and migration were evaluated by microinvasion assay. The variation of expression percentages of MMP2- or MMP9-positive cells was detected by flow cytometry in two cell lines with or without MIF treatment. Western blotting and RT-PCR were used to assay the protein and mRNA expressions of MMP2 and MMP9. The IL-8 concentration secreted by NPC cells was compared with the cells with different treatments using ELISA. Results After treating with MIF for 48 hours, the cell numbers of CNE-1 and CNE-2 which went through the 8-μm filter membrane were increased. Compared with non-MIF treated NPC cells,significant difference could be found both in CNE-1 (P=0.005)and CNE-2 cells (P=0.001) . The percentages of MMP9-positive cells were significantly increased in both CNE-1 [from (28. 5 ±2. 5)%to (82. 4 ±3. 5)%, P=0. 001] and CNE-2 [from (32. 8 ±3. 5)% to (86. 1 ±1.6)%, P=0. 002]. The relative intensity of MMP9 protein expression was also enhanced in both cell lines (CNE-1: from 83. 1 ±6. 0 to 242. 9 ±22. 9, P=0. 002; CNE-2: from 84. 4 ±4. 3 to 278. 9 ±29. 7, P=0. 003). Correspondingly, the increased MMP9 mRNA expression level was significantly detectable in both cell lines. The concentration of IL-8 in the supernatant of CNE-2 was higher [(1201. 8 ±593. 3) pg/ml]after treatment. It was also remarkably higher than that in the supernatant of CNE-2 without treatment(P=0.026). However, there was no significant difference in the concentration variation of IL-8 in CNE-1 (P=0. 581), while the IL-8 mRNA level was only enhanced in CNE-2. Conclusions MIF can induce potent invasion of NPC cell lines in vitro, and the infiltrating lymphocytes in NPC might be responsible for the invasion and metastasis of tumor cells. MIF cytokine which is secreted by these infiltrating lymphocytes might contribute to the invasion as well as metastasis of NPC in the early stages by induction of MMP9 and IL-8 in an indirect pathway. Chin Med J 2004; 117(1): 107-114

Background There were only 3 multiple myeloma (MM) cell lines established in China. In this study, we succeeded in establishing a novel MM cell line and analyzed its biological characteristics. Methods Mononuclear cells isolated from the peripheral blood (PB) and bone marrow (BM) of a patient with advanced MM (λ light chain type) were cultured in medium. Cell morphology was analyzed by Wright-Giemsa-staining and cytochemical staining, immunophenotyping by flow cytometry and cytogenetic analysis by chromosome RHG-banding technique. Quantitative fluorescent polymerase chain reaction (PCR) was used to detect Epstein - Barr virus (EBV) DNA. Results The established cell line could survive and proliferate in the presence of feeder cells or conditioned medium. The cells secreted λ light chain and were negative for EBV. The Wright-Giemsa-staining showed typical plasmablast or plasma cell morphology. The cytochemical staining of the cells showed the following reactivity patterns: positive for acid phosphatase, negative for myeloperoxidase. The immunoprofile of the cells was concordant with that of MM cells: positive for CD10, CD28, CD38,CD138, CD56, CD49d, CD44, CD54 and CD58, negative for CD19, CD40, CD95, CD95L, CD34, CD2 and CD5. The cytogenetic analysis showed complex chromosome abnormality of i (1 q+), 8q+, 13q+, i(17q), i (18q) and + M. There was no difference in morphology, immunophenotype and cytogenetics between cells from PB and BM. Conclusions An MM cell line secreting λ light chain named CZ-1 was established. The cells from both PB and BM have the same biological characteristics. Chin Med J 2004; 117(1): 115-119

Background Neonatal respiratory distress syndrome (NRDS) is caused by a deficiency in pulmonary surfactant (PS) and is one of the main reasons of neonatal mortality. This study was conducted to evaluate the efficacy and safety of intra-amniotic administration of pulmonary surfactant for prophylaxis of NRDS. Methods Forty-five pregnant women who were due for preterm delivery and whose fetuses' lungs proved immature were divided into two groups. Fifteen women (study group) were administered one dose of pulmonary surfactant injected into the amniotic cavity and delivered within several hours. Nothing was injected into the amniotic cavity of 30 women of the control group. The proportion of neonatal asphyxia, NRDS, mortality and the time in hospital were analyzed to determine if there was any difference between the two groups. Results There was no significant difference between the two groups for neonatal asphyxia. Foam tests showed that higher proportion of neonates in the study group than in the control group (56. 3%vs 13. 3%, P<0. 05) had lung maturity. A greater number of control neonates (11/30, 32. 3%) had NRDS, compared with the neonates given PS via the amniotic cavity before delivery (1/16, 6. 3%, P<0. 05). The neonates in the study group spent nearly 10 days less in hospital than the control group[(32. 4 ±7. 6) days vs (42. 0 ±15. 7) days, P <0. 05], but the difference in mortality between the two groups was not statistically significant. Conclusions Intra-amniotic administration of pulmonary surfactant can significantly reduce the proportion of NRDS and the time in hospital of preterm neonates. Whether this method can reduce the mortality of preterm neonates needs to be evaluated further. Intra-amniotic administration of pulmonary surfactant provides an additional effectual means for NRDS prophylaxis. Chin Med J 2004; 117(1): 120-124

Background Severe acute respiratory syndrome (SARS) is characterized by both an atypical pneumonia and efficient nosocomial transmissin. However, it remains unknown whether the infectivity and the virulence of the pathogen will change throughout the successive transmission. This study was conducted to compare the clinical features and management regimens of patients with SARS among the multiple generations from nosocomial transmission initiated by a super-spreader. Methods The clinical data of 84 epidemiologically-linked SARS patients from a hospital outbreak were retrospectively studied. All patients, in whom a clear-cut transmission generation could be noted,had a direct or indirect exposure to the index patient and the epidemic successively propagated through the multiple generations of cases within a short period of time. Results There were 66 women and 18 men with mean age of (29. 2 ± 10. 3) years in this cluster;and 96. 4%of whom were health care workers. Detailed contact tracing identified 35 (41. 7%) first-generation cases, 34 (40. 5%) second-generation cases, and 15 (17. 8%) third-generation cases. No statistical differences among the multiple generations of transmission were found in terms of age,gender, incubation period and length of hospital stay. With the advanced transmission generations, the initial temperature lowered, the number of cases with dry cough decreased. There were no statistical differences in the peak temperature and duration of fever, other accompanying symptoms,leucopenia; however, the time from initial pulmonary infiltrates to radiographic recovery shortened(P<0. 05). No differences were found in maximum number of lung fields involved, duration from the onset of fever to the occurrence of pulmonary infiltrates and time from the initial pulmonary infiltrate to its peak among the multiple transmission generations (P>0. 05). No statistical differences were found in modes of oxygen therapy and sorts of antibiotics prescribed among the various transmission generations (P> 0. 05); however, as with the advanced transmission generations, the number of cases prescribed with methylprednisolone, human γ-globulin, interferon-a, antiviral drugs (oral ribavirin or oseltamivir) increased (P <0. 05) and time from admission to starting these medication shortened (P <0. 05). Conclusions There is no evidence that SARS infection will evolve or transmit within a fashion that permits it to become less powerful throughout the successive transmission within a short time. Chin Med J 2004; 117(1): 14-18

Background Chronic hypoxia can cause pulmonary hypertension and pulmonary heart disease with high mortality. The signal transduction pathway of protein kinase C (PKC) plays an important role in chronic pulmonary hypertension. So it is necessary to investigate the effect of PKC on voltage-gated potassium (K+) channels in pulmonary artery smooth muscle cells of rats exposed to chronic hypoxia. Methods Male Wistar rats were randomly divided into a control group (group A) and a chronic hypoxia group (group B). Group B received hypoxia [oxygen concentration (10 ±1)%] eight hours per day for four consecutive weeks. Single pulmonary artery smooth muscle cells were obtained using an acute enzyme separation method. Conventional whole cell patch clamp technique was used to record resting membrane potential, membrane capacitance and voltage-gated K+ currents. The changes in voltage-gated K+ currents before and after applying paramethoxyamphetamine (PMA)(500 nmol/L), an agonist of PKC, and PMA plus carbohydrate mixture of glucose, fructose and xylitol (GFX) (30 nmol/L), an inhibitor of PKC, were compared between the two groups. Results The resting membrane potential in group B was significantly lower than that of group A:-(29. 0 ±4. 8) mV (n=18) vs -(42. 5 ±4. 6) mV (n=35) (P <0. 01). But there was no change in membrane capacitance between the two groups: (17. 9 ± 4. 6) pF (n=40) vs (19. 7 ± 5. 8)pF (n=31) (P>0. 05). The voltage-gated K+ currents were significantly inhibited by PMA in group A, and this effect was reversed by GFX. However, the voltage-gated K+ currents in group B were not affected by PMA. Conclusions The resting membrane potential and voltage-gated K+ currents in pulmonary artery smooth muscle cells from rats exposed to chronic hypoxia decreased significantly. It seems that PKC has different effects on the voltage-gated K+ currents of pulmonary artery smooth muscle cells under different conditions. Chin Med J 2004; 117(1): 19-23

Background Asthma is clinically related with the degree of eosinophilic inflammation. How asthmatic airway inflammation is affected is still poorly understood. So the effects of bone marrow-derived hematopoietic cells expressing CD34 (CD34+) and interleukin-5 (IL-5) receptor messenger RNA(IL-5R mRNA+) on asthmatic airway inflammation were investigated. Methods Balb/c mice were sensitized and challenged by ovalbumin (OVA) to establish an asthmatic model while control mice were sensitized and exposed to sterile saline. The mice were killed at different time points after being challenged by OVA and sterile saline. Then, bronchoalveolar lavage fluid (BALF), peripheral blood (PB) and bone marrow (BM) were prepared. Eosinophils in PB(PBEOS) and BALF (BALFEOS), nuclear cells in BALF, PB and BM were counted. By flow cytometry, the percentage of CD34+ cells to nucleated cells in PB, BM and the relative number of CD34+ cells in PB (PBCD34+) and BM (BMCD34+) were calculated. Immunocytochemistry and in situ hybridization were used to investigate the hematopoietic cells with co-localized expression of CD34 and IL-5R mRNA in BM (BMCD34+ IL-5R mRNA+). The percentage of BMCD34+ IL-5R mRNA+ to BMCD34+ was calculated. Results Twelve hours after challenge by OVA, BALFEOS and PBEOS in the experimental group were significantly higher than those in the control group (P <0. 01) . Twenty-four hours after OVA challenge, BALFEOS, PBEOS and BMCD34+ IL-5R mRNA+ were elevated maximally, significantly different from those in the control group (P <0. 01) . Forty-eight hours after OVA challenge, BALFEOS and BMCD34+ IL-5R mRNA+ were still significantly higher than those of the controls (P <0. 01). The other markers reverted to normal. In 60 mice, BMCD34+ IL-5R mRNA+ was closely correlated with the BALEOS,PBEOS, BMCD34+ and BMCD34+(%) (P<0. 05). Conclusions The amount of CD34+ cells expressing IL-5R mRNA increased in the BM of asthmatic model mice, which favors eosinophilopoiesis and eosinophilic airway inflammation. A signal pathway exists between the lungs and the bone marrow, which is involved in the initiation and maintenance of asthmatic airway inflammation. Chin Med J 2004; 117(1): 24-29

Background Airway smooth muscle proliferation plays an important role in airway remodeling in asthma. But little is known about the intracellular signal pathway in the airway smooth muscle cell proliferation in asthma. The objective of this paper is to investigate the contribution of protein kinase C(PKC) and its alpha isoform to passively sensitized human airway smooth muscle cells (HASMCs)proliferation. Methods HASMCs in culture were passively sensitized with 10%serum from asthmatic patients,with non-asthmatic human serum treated HASMCs used as the control. The proliferation of HASMCs was examined by cell cycle analysis, 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyltetrazoliumbromide(MTT) colorimetric assay and proliferating cell nuclear antigen (PCNA) immunofluorescence staining. The effect of PKC agonist phorbol 12-myristate 13-acetate (PMA) and PKC inhibitor Ro-31 -8220 on the proliferation of HASMCs exposed to human asthmatic serum and non-asthmatic control serum was also examined by the same methods. The protein and mRNA expression of PKC-a in passively sensitized HASMCs were detected by immunofluorescence staining and reverse transcription-polymerase chain reaction. Results The percentage of S phase, absorbance (value A) and the positive percentage of PCNA protein expression in HASMCs passively sensitized with asthmatic serum were (16. 30 ± 2.68)%,0. 430 ±0.060 and (63. 4 ±7.4)% respectively, which were significantly increased compared with HASMCs treated with control serum [(10. 01 ±1.38)%, 0. 328 ± 0.034 and (37. 2 ±4.8)%,respectively] (P <0. 05). After HASMCs were passively sensitized with asthmatic serum, they were treated with PMA, the percentage of S phase, value A and the positive percentage of PCNA protein expression were (20. 33 ± 3.39)%, 0. 542 ± 0.065 and (76. 0 ± 8. 7)% respectively, which were significantly increased compared with asthmatic serum sensitized HASMCs without PMA(P <0. 05). After HASMCs passively sensitized with asthmatic serum were treated with Ro-31 -8220, the percentage of S phase, value A and the positive percentage of PCNA protein expression were (11. 21±1.56)%, 0. 331 ±0.047 and (38. 8 ±6.0)% respectively, which were significantly decreased compared with asthmatic serum sensitized HASMCs without Ro-31 -8220 (P <0. 05). The relative ratio of value A of PKC-a mRNA and the positive percentage of PKC-a protein expression in passively sensitized HASMCs were 1.23 ±0.10 and (61. 1 ±9. 4)% respectively, which were significantly increased compared with HASMCs treated with control serum [1. 05 ± 0.09 and (34.9 ±6.7)%, respectively] (P<0. 05). Conclusions The proliferation of HASMCs passively sensitized with human asthmatic serum is increased. PKC and its alpha isoform may contribute to this proliferation. Chin Med J 2004; 117(1): 30-36

Background Human urotensin Ⅱ (U Ⅱ) is the most potent mammalian vasoconstrictor identified so far. Our previous study showed that U Ⅱ is a potent mitogen of airway smooth muscle cells (ASMC)inducing ASMC proliferation in a dose-dependent manner. The signal transduction pathway of U Ⅱmitogenic effect remains to be clarified. This study was conducted to investigate the signal transduction pathway in the proliferation of ASMC induced by U Ⅱ. Methods In primary cultures of rat ASMCs, activities of protein kinase C (PKC), mitogen-activated protein kinase (MAPK) and calcineurin (CaN) induced by U Ⅱ were measured. The effect of CaN on PKC and MAPK was studied by adding cyclosporin A (CsA), a specific inhibitor of CaN. Using H7 and PD98059, inhibitors of PKC and MAPK, respectively, to study the effect of PKC and MAPK on CaN. The cytosolic free calcium concentration induced by U Ⅱ was measured using Fura-2/AM. Results U Ⅱ 10-7 mol/L stimulated ASMC PKC and MAPK activities by 44%and 24%(P<0. 01),respectively, after incubating for 20 minutes. It increased CaN activity in a time-dependent manner, being 1. 68 times as that of control for 24 hours (P <0. 01). It promoted the cytosolic free calcium concentration increase of 18%(P <0. 01). CsA 10-6 mol/L and H7 50 µmol/L inhibited U Ⅱ -stimulated CaN activity by 45%(P <0. 01) and 21 %(P <0. 05), respectively, while PD9805950 μmol/L had no effect on CaN activity (P> 0. 05). CsA 10-6 mol/L inhibited U Ⅱ -stimulated PKC activity by 14%(P <0. 05), while having no effect on MAPK activity (P> 0. 05). Conclusions U Ⅱ increases cytosolic free calcium concentration and activates PKC, MAPK and CaN. The signal transduction pathway between PKC and CaN has cross-talk. Chin Med J 2004; 117(1): 37-41

Background SARS-CoV is the causative agent of severe acute respiratory syndrome (SARS) which has been associated with outbreaks of SARS in Guangdong, Hong Kong and Beijing of China, and other regions worldwide. SARS-CoV from human has shown some variations but its origin is still unknown. The genotyping and phylogeny of SARS-CoV were analyzed and reported in this paper. Methods Full or partial genomes of 44 SARS-CoV strains were collected from GenBank. The genotype, single nucleotide polymorphism and phylogeny of these SARS-CoV strains were analyzed by molecular biological, bioinformatic and epidemiological methods. Results There were 188 point mutations in the 33 virus full genomes with the counts of mutation mounting to 297. Further analysis was carried out among 36 of 188 loci with more than two times of mutation. All the 36 mutation loci occurred in coding sequences and 22 loci were non-synonymous. The gene mutation rates of replicase 1 AB, S2 domain of spike glycoprotein and nucleocapsid protein were lower (0. 079% - 0. 103%). There were 4 mutation loci in S1 domain of spike glycoprotein. The gene mutation rate of ORF1O was the highest (3. 333%) with 4 mutation loci in this small domain(120 bp) and 3 of 4 loci related to deletion mutation. By bioinformatics processing and analysis, the nucleotides at 7 loci of genome (T: T: A: G: T: C: T/C: G: G: A: C: T: C) can classify SARS-CoV into two types. Therefore a novel definition is put forward that according to these 7 loci of mutation, 40strains of SARS-CoV in GenBank can be grouped into two genotypes, T: T: A: G: T: C: T and C: G: G: A: C: T: C, and named as SARS-CoV Yexin genotype and Xiaohong genotype. The two genotypes can be further divided into some sub-genotypes. These genotypes can also be approved by phylogenetic tree of three levels of 44 loci of mutation, spike glycoprotein gene and complete genome sequence. Compared to various strains among SARS-CoV Yexin genotype and Xiaohong genotype, GD01 strain of Yexin genotype is more closely related to SARS-CoV like-virus from animals. Conclusion The results mentioned above suggest that SARS-CoV is responding to host immunological pressures and experiencing variation which provide clues, information and evidence of molecular biology for the clinical pathology, vaccine developing and epidemic investigation. Chin Med J 2004; 117(1): 42-48

Objective To summarize current understanding of the roles of anti-inflammatory and proinflammatory mechanisms in the development of atherosclerosis and acute coronary syndrome and to postulate the novel concept of inflammation stress as the most important factor triggering acute coronary syndrome. Moreover, markers of inflammation stress and ways to block involved pathways are elucidated. Data sources A literature search (MEDLINE 1997 to 2002) was performed using the key words "inflammation and cardiovascular disease." Relevant book chapters were also reviewed. Study selection Well-controlled, prospective landmark studies and review articles on inflammation and acute coronary syndrome were selected. Data extraction Data and conclusions from the selected articles providing solid evidence to elucidate the mechanisms of inflammation and acute coronary syndrome were extracted and interpreted in the light of our own clinical and basic research. Data synthesis Inflammation is closely linked to atherosclerosis and acute coronary syndrome. Chronic and long-lasting inflammation stress, present both systemically or in the vascular walls, can trigger acute coronary syndrome. Conclusions Inflammation stress plays an important role in the process of acute coronary syndrome. Drugs which can modulate the balance of pro- and anti-inflammatory processes and attenuate inflammation stress, such as angiotensin-converting enzyme (ACE) inhibitors/angiotensin II receptor blockers, statins, and cytokine antagonists may play active roles in the prevention and treatment of acute coronary syndrome when used in addition to conventional therapies (glycoprotein II b/ III a receptor antagonists, mechanical intervention strategies, etc). Chin Med J 2004; 117(1): 133-139