2002年 · 第115卷第11期

Objective To evaluate the feasibility, safety and diagnostic accuracy of pharmacologic stress of 99mTechnetium-MIBI single-photon emission computed tomography (SPECT) with intravenous adenosine triphosphate (ATP) in patients with suspected coronary artery disease. Methods The study group included 263 patients who were suspected of having coronary artery disease. All patients underwent 99mTc-MIBI myocardial perfusion imaging with ATP infusion (0.16 mg/kg body weight per min for 5 min). 20 mCi of 99mTc-MIBI were injected 3 minutes after the start of ATP infusion. Myocardial SPECT images were obtained 60 minutes later. Then, two days later, 20 mCi of 99mTc-MIBI were administered at rest and myocardial SPECT was repeated. 51 patients also underwent coronary angiography within two weeks for evaluation of sensitivity and specificity of ATP-myocardial perfusion imaging in detection of coronary artery disease. The occurrence of cardiac and non-cardiac adverse effects was carefully monitored during and after intravenous ATP infusion. Results The ATP infusion protocol was completed in all patients. Although 59% of the patients had various kinds of adverse effects, most of them were mild. No patient required aminophyline. The most severe adverse effect was second degree type Ⅱ atria-ventricular block (4/263), but all events were transient. The sensitivity and specificity of ATP-myocardial perfusion imaging were 97% and 82%, respectively. Conclusions It is shown that 99mTechnetium-MIBI SPECT with intravenous ATP is a safe and feasible technique for detecting coronary artery disease in patients unable to perform the exercise test. Chin Med J 2002; 115(11): 1603-1607

Objective To investigate the effect and mechanism of arsenic trioxide (As2O3) on the prevention of restenosis after vascular injury. Methods Apoptosis induction of As2O3 on cultured rabbit vascular smooth muscle cells (VSMCs) in vitro was observed. Thirty-two New Zealand white rabbits were randomly divided into 2-and 4-wk study groups, and their controls. 10% As2O3 at 2.5 mg• Kg-1 • d-1 or 0.9% sodium chloride was intraperitoneally infused for 3 days before left common carotid arteries were denudated with a balloon. After denudation 2-and 4-wk animals were sacrificed for morphometry and immunohistochemical studies on carotid arteries, and for histopathology on liver and kidney. Results It was shown via cellular morphology and DNA fragments in electrophoresis that promotion of As2O3 on cultured vascular smooth muscle cell apoptosis was dependent upon its concentration and duration. Compared with the control animals, the mean vascular intimal proliferation areas were reduced in 2-wk study animals (P < 0.05) and no difference was shown in 4-wk (P > 0.05), while the mean vascular luminal areas were all enlarged in both study groups (all P < 0.05). The downregulated bcl-2 expression (all P < 0.05 in 2-and 4-wk) and the upregulated bax expression (P < 0.01 in 2-wk; P < 0.05 in 4-wk) were detected by immunohistochemistry, in comparison with control groups. Gene bcl-2 and bax protein expression were consistent with the suppression of intimal proliferation and the enlargement of luminal areas in corresponding sections. Conclusion As2O3 induces apoptosis of VSMCs and inhibits experimental restenosis effectively after artery injury, via downregulation of bcl-2 and upregulation of bax expression. Chin Med J 2002; 115(11): 1608-1614

Objective To investigate the relationship between the expression of glucose regulated protein 94 (GRP94) at the level of mRNA and protein in vivo and in human lung cancer. Methods RT-PCR, immunohistochemistry and/or Western blot were used in 54 cases of lung cancer tissues and corresponding normal lung tissues. Results There was a significant overexpression of GRP94 mRNA and protein in lung cancer tissues as compared with lung normal tissues. In lung cancer tissue, the relative level of GRP94 mRNA as evaluated by RT-PCR was 3.48 ± 2.06, the level of GRP94 protein as evaluated by immunohistochemistry was + + to + + +, and by Western blot was 256.7 ± 80.6. In lung normal tissue, the relative level of GRP94 mRNA was 2.01 ± 1.83, the level of GRP94 protein was + to + + and 108.1 ± 42.3. The differences in expression of GRP94 between the two tissues were significant (P < 0.05). Furthermore, the over-expression of GRP94 in the lung cancer tissues was correlated to grade of differentiation and stage of tumors. There was stronger expression in poor-differentiated tumors than in mild-to-high differentiated tumors (P < 0.05). There was also a stronger expression in stage Ⅲ than in stage Ⅰ and Ⅱ tumors (P < 0.05). No statistically significant difference was found among various pathological types of tumors. Conclusion GRP94 was related with the occurrence, differentiation and progress of human lung cancer. Ascertaining the levels of GRP94 mRNA and protein may be valuable in evaluating the grade of differentiation and clinical stage of human lung cancer. Chin Med J 2002; 115(11): 1615-1619

Objective To study the effects of low-molecular weight heparin (LMWH) and adrenocortical hormone (dexamethasone) on the hemolysis of red cells of patients with paroxysmal nocturnal hemoglobinuria (PNH) in vitro. Methods Using Ham's test and micro-complement lysis sensitive test (mCLST), the changes in hemolysis of red cells from 6 typical PNH cases were examined after adding LMWH and dexamethasone in different concentrations into the test solution in vitro. The effects of LMWH and dexamethasone on the coagulation of the tested blood samples were also studied using the activated partial thromboplastin time (APTT) test. Results Both LMWH and dexamethasone inhibited the hemolysis of PNH red cells, and they also showed a synergistic effect. The inhibiting effects were dose-dependent. Moreover, a tolerable dose of LMWH induced a limited prolongation of APTT. Dexamethasone showed two possible mechanisms in the inhibition of PNH red cells hemolysis through Ham's test and mCLST, respectively: ① inhibiting both antibodies binding to red cells and ② the initiation of the activation of complement 3 (C3). LMWH could inhibit hemolysis as determined by both Ham's test and mCLST, which indicated that LMWH could block the activation of complement cascade. Conclusions Both LMWH and dexamethasone could inhibit hemolysis in PNH, and they showed a synergistic effect. Their mechanisms of inhibiting hemolysis differed from each other. Furthermore, a tolerable dose of LMWH induced a limited prolongation of APTT. LMWH might be useful for controlling acute hemolysis in patients with PNH and reducing the dose of adrenocortical hormone. Chin Med J 2002; 115(11): 1620-1623

Objective To clone and study the polymorphism within interleukin-4 (IL-4) proximal promoter of asthmatic children. Methods The IL-4 proximal promoter segments were amplified and selected by polymerase chain reaction (PCR) and single strand conformation polymorphism (SSCP) with genomic DNA from ten healthy children and forty patients with dominantly allergic familial histories as templates. The selected PCR segments were cloned into recombinant plasmids pIL-4-Jx2. The PCR inserts were sequenced by dideoxy chain termination method. Results Seven aberrant bands were found in SSCP analysis from forty asthmatic patients. The sequencing results showed that four variant sites were found within or adjacent to the known IL-4 regulatory element. A C to A transversion located at -229 position was just within the positive regulatory element- Ⅰ(PRE- Ⅰ) in one patient. A C to T transition adjacent to the negative regulatory element- Ⅱ (NRE- Ⅱ) and an extra G adjacent to TATA box were found in two patients. A five base nucleotide deletion was found near signal transducers and activators of transcription-6 responsive element (STAT-6 RE) in one patient. Conclusion There were polymorphisms within the IL-4 proximal promoter of allergic asthmatic patients and these polymorphisms might result in aberrant expression of IL-4 gene and asthma. Chin Med J 2002 ; 115(11): 1624-1627

Objective To observe trinucleotide repeat number, (CTG)n in the 3' -untranslated region of the myotonic protein kinase (MTPK) gene in a clinically suspected woman with myotonic dystrophy (DM) family history and her abortus, in order to confirm the necessity of exerting antenatal examination in patients or suspected individuals with DM family history. Methods Long Expand ™Template polymerase chain reaction (PCR) system was used to analyze CTG trinucleotide repeat numbers located in the 3' untranslated region of MTPK on chromosome 19q13.2-3 in both peripheral white cells and muscles of the suspected mother and the other two DM patients in the family. The tissues of her abortus and blood of a health woman were detected, too. Results CTG repeats in both peripheral white cells and muscles of the suspected mother and the tissue of abortus were higher than normal range of CTG repeat number. There is no significant difference between blood and muscle samples. High CTG repeats were detected in blood and muscles of the typical DM members in the family, but in the blood sample of control, CTG repeats is normal. Conclusion CTG trinucleotide analyses and antenatal examination should be done in pregnant with a DM family history, in order to reduce the birth rate of DM offspring. Chin Med J 2002; 115(11): 1628-1631

Objective To explore new methods for the early diagnosis of pancreatic cancer through detection of K-ras and p53 mutations in pancreatic juice and stool. Methods 201 patients in PUMC Hospital from 1994 - 2000 and 60 control individuals were enrolled in this study. K-ras point mutation was detected by PCR-RFLP while p53 mutation was detected by PCR-SSCP. Results K-ras mutation was found in pancreatic juice in 87.8% (36/41) of pancreatic cancer patients and 23.5% (4/17) of benign pancreatic disease patients. In 261 stool specimens, amplification found mutations successfully in 235 patients (90%). K-ras mutation was found in stool in 88% (66/75) of pancreatic cancer patients, 51.1% (24/47) of benign pancreatic disease patients and 19.6% (9/46) of normal individuals. p53 mutation was found in pancreatic juice in 47.4% (18/38) of pancreatic cancer patients and 12.5% (2/16) of benign pancreatic disease patients. p53 mutation was found in stool in 37.1 % (23/62) and 19.1% (4/21) of chronic pancreatitis patients. Conclusion K-ras mutation in pancreatic juice has higher diagnosis sensitivity and specificity, and therefore may be used as a supplement in the diagnosis of pancreatic cancer. Detection of K-ras mutation combined with p53 mutation in stool can aid in the screening of pancreatic cancer. Chin Med J 2002; 115(11): 1632-1636

Objective To study the role of the synthesis and degradation of collagen at the transcription level during liver fibrogenesis due to schistosomiasis japonica in rabbits. Methods New Zealand rabbits challenged by cercariae of Schistosoma japonicum (S. japonicum) were served as animal models for liver fibrosis. Liver specimens were collected through operations at 4, 6, 8, 10, 12, 16, 20, 24 and 28 wks after challenge. Type I collagen, type Ⅲ collagen, type Ⅳ collagen, MMP-1 and MMP-9 mRNA levels of liver tissue were detected by RT-PCR + Dot blot. The size of egg granulomas and the degree of liver fibrosis were measured by histopathological examinations. Results Type I collagen, type Ⅲ collagen, type Ⅳ collagen, MMP-1 and MMP-9 mRNA levels increased simultaneously in the early stage after challenge. Most of them reached their peak at 10 weeks, and compared with normal controls, type Ⅰ collagen, type Ⅲ collagen, type Ⅳ collagen, MMP-1 and MMP-9 mRNA levels increased by 12.0-, 11.0-, 6.6-, 10.0- and 11.0-fold, respectively, coinciding with the change of egg granulomas, i.e., the change in the inflammatory process. Then both collagen and collagenase mRNA levels decreased. Type Ⅰ, Ⅲ and Ⅳ collagen mRNA levels declined to 2-fold to 3-fold as compared with normal controls (P < 0.05), while MMP-1 and MMP-9 mRNA levels declined close to normal levels (P > 0.05) at 28 wks. This study shows that the synthesis and degradation of collagen keep a dynamic balance at the early stage of schistosomiasis japonica challenge, while at the later stages the quantity of collagen synthesis was higher than that of collagen degradation. Conclusions It was confirmed at transcription level that when the quantity of collagen synthesis was higher than that of collagen degradation liver fibrogenesis may be resulted in. Chin Med J 2002; 115(11): 1637-1640

Objective To demonstrate the molecular expression of carbonic anhydrase Ⅳ (CA Ⅳ) in rabbit corneal endothelium. Methods Reverse transcriptase polymerase chain reaction (RT-PCR) was performed using cultured and fresh rabbit corneal endothelial total RNA and specific primers for CA Ⅳ. The RT-PCR product was subcloned and sequenced. Immunoblotting and indirect immunofluorescence staining were performed to detect protein expression and distribution of CA Ⅳ using fresh and cultured rabbit corneal endothelium and rat anti-CA Ⅳ polyclonal antibody. Results RT-PCR screening gave positive bands at the predicted size for CA Ⅳ from fresh and cultured rabbit corneal endothelium. Sequencing further confirmed the identity of CA Ⅳ in corneal endothelium. Immunoblotting analysis showed a single band at 52 kDa for freshly isolated and cultured endothelial cells. Indirect immunofluorescence staining revealed an apparent positive staining in cultured endothelial cells. Conclusion Carbonic anhydrase Ⅳ is expressed in rabbit corneal endothelium, which could contribute to the transendothelial HC03 flux that is necessary to maintain corneal hydration and transparency. Chin Med J 2002; 115(11): 1641-1644

Objective To investigate the reasons for the rarity of metastases in skeletal muscle. Methods By injecting tumor cells (Walker256 rat carcinosarcoma) through the iliac artery (experimental group) and the tail vein (control group), animal models of blood-borne metastases were established. The quadriceps femoris muscle and lungs were observed grossly and microscopically. Immunohistochemistry was applied to investigate the expression of vascular cell adhesion molecule-1 (VCAM-1) in the microvascular endothelium of these organs. Primary culture of rat skeletal muscle cells was established and conditioned medium (MCM) was collected. Effects of MCM on several tumor cell lines and the biochemical characteristics of skeletal muscle delivered tumor factor(s) were tested by MTT assay. Apoptosis and morphological examination were carried out to investigate the antitumor mechanisms of MCM. Results In the experimental group, there were no definite metastases observed in muscle cells. In the control group, lung metastases were present in the lungs of all rats that were sacrificed at the 14th day or died spontaneously (17 rats in all). There was no significant difference between the increase in VCAM-1 in quadriceps femoris muscle 7 days after iliac artery injection and that in lungs 7 days after tail vein injection (P > 0.05). In vitro studies showed that the proliferation of tumor cell lines of mouse SP2/0 myeloma, rat Walker256 carcinosarcoma or human chronic granulocytic leukemia K562, human acute lymphatic leukemia HL-60, LS-174-T colon adenocarcinoma, PC3-M prostatic carcinoma and lung giant cell carcinoma with different metastatic potency (PLA801-C with low metastatic potency, PLA801-D with high metastatic potency) was significantly inhibited when cultured with MCM (P < 0.01 - 0.05). Proliferation of malignant cells showed a dose-dependent decrease, to a certain degree. Proliferation of normal rabbit joint epiphysial disk cells (RGP-2) were not affected by MCM. Proliferation of lung giant cell carcinoma cells with high metastatic potency showed a significant decrease even when cultured in highly diluted MCM (6.25% of primary MCM), when compared with the strain of low metastatic potency. Following ultrafiltration, boiling at 100℃, and treatment with trypsin, skeletal muscle delivered tumor factor(s) were found to be a low molecular weight (MW≤1O.O KDa) component which was trypsin resistant but not heat resistant. The factor(s) did not induce apoptosis in K562 cells but caused direct destruction of the cytoplasmic membrane. Conclusions The rarity of metastases in skeletal muscles, generally accepted in the clinical setting, can be reproduced in an animal model. It does not seem to be related to VCAM-1 expression in the microvessels of these organs. Skeletal muscle delivered factor(s) play a key role in the mechanism of the rarity of metastases in skeletal muscle. Chin Med J 2002; 115(11): 1645-1649

Objective To approach the sequential release of antitumor drugs and promote the effect of chemotherapy. Methods Adriamycin (ADM) and carboplatin (CBP) were respectively microcapsulated with ethylcellulose by organic phase separation. The morphology and sizes of the microcapsules were observed and measured with light microscope and scanning electromicroscope. The contents and the release rates of ADM and CBP in microcapsules were measured with fluorescence spectrophotometer and high-efficiency phantom chromatic (HPC) spectrum respectively. The antitumor sensitivity test in vitro was devised with MTT assay. Results The microcapsules of ADM and CBP were spherical in shape with diameters of 196 ± 64 μm and 214 ± 48 μm respectively. The contents of one-layer and two-layer CBP and ADM microcapsules were 51.4%, 35.7% and 39.8% respectively, with the release rates in vitro of 62.4%/day, 54.8%/day and 48.2% /8h. The results of drug sensitivity test in vitro demonstrated that the current preparation has never affected the stability and antitumor activity of CBP and ADM. Conclusion Microcapsules with different drugs and different thickness of material have different release rate. Combined arterial chemoembolization with different microcapsules could approach the sequential release and promote the effect of chemotherapy. Chin Med J 2002; 115(11): 1730-1732

Objective Wolff-Parkinson-White syndrome (WPW) is considered to be an autosomal dominant hereditary disease, but the gene is not identified. The objective of this study was to localize the genetic loci of Wolff-Parkinson-White syndrome. Methods Linkage analysis between the disease of Wolff-Parkinson-White syndrome and 3 STR (short tandem repeats) markers on 7q3 (D7S505, D7S688, and D7S483) was tested in 3 kindreds of the Wolff-Parkinson-White syndrome (101 numbers in total) by genotyping. Results Wolff-Parkinson-White syndrome was linked to the loci above. The maximum two-point Lod score detected at D7S505 was 6.4 at a recombination fraction (0) of 0.1; the Lod score of D7S688, D7S483 was 5.3 vs 2.5. Conclusion The gene of Wolff-Parkinson-White syndrome is located at 7q3. Chin Med J 2002; 115(11): 1733-1735

Objective To investigate a non-invasive, effective and rapid mode of detecting the recurrence of bladder cancer during follow-up. Methods Ninety patients following transurethral resection of bladder tumor (TURBt) surgery were recruited from January 1998 to March 2000. Standard ELISA was used to determine the quantity of nuclear matrix protein (NMP-22) in urine of all bladder cancer patients during their follow-up periods. Urine bladder tumor antigen (BTA) stat test was simultaneously performed and followed by cystoscopy. Results The total positive rates of urinary NMP-22 and BTA stat test were 76.7% (33/43) and 67.4%(29/43), respectively. Comparatively, this positive rate would increase to 93.0% (40/43) when the combination of both urine NMP-22 and BTA test were adopted. Conclusion Examination of NMP-22 in urine is a rapid and effective way to detect the recurrence of bladder cancer. If combined with BTA test, NMP-22 may be used as a non-invasive method in surveillance of recurring of bladder cancer, which may reduce the frequency of patients needing to undergo conventional invasive cystoscopy. Chin Med J 2002; 115(11): 1736-1738

Objective To study the esthetic and long-term effectiveness of cerinate porcelain laminate veneers. Methods A total of 736 front teeth were restored with cerinate porcelain laminate veneers, which were then tested at different time points by clinical tracking observation and appraisal. Results The short and long term rates of effectiveness were 96.6% and 96.2%, respectively. There was no relationship between clinical effectiveness and the length of restoration time. The failure rate was higher in 18 - 30 years old patients and those with discolored teeth. The major clinical performance was fold fissure and deciduous of porcelain laminate veneers. Conclusions Cerinate porcelain laminate veneers are an ideal choice for dental esthetic restorations because they are unnoticeable, stable, strong and require no excessive dental preparation. Chin Med J 2002; 115(11): 1739-1740

Objective To review the major progress in primary angle closure glaucoma (PACG). Methods Contents of this article were selected from the original papers or reviews related to primary angle closure glaucoma published in Chinese and foreign journals. A total of 76 articles were selected from several hundred original articles or reviews. The content of selected articles is in accordance with our purpose and the authors are authorized scientists in the study of glaucoma. Results Primary angle closure glaucoma is the most common type of glaucoma in the Sino-Mongoloid population. PACG in Chinese can be classified into three types depending on the mechanism of angle closure: 1. Multimechanism: 54.8% of Chinese PACG is caused by co-existing factors. The pattern of angle closure appears to mainly be creeping closure. After iridectomy, almost 40% of the cases still manifest a positive response to the darkroom provocative test and progressive synechial closure or recurrent angle closure may occur. Several mechanisms are involved in this form of PACG such as pupillary blocking component, iris crowding component and anterior positioned ciliary body. These factors can coexist in the follow patterns: pupillary blocking and iris crowding coexist; pupillary blocking and anterior positioned ciliary body coexist or three of them co-exist. 2. Pupillary block: (38.1% of Chinese PACG) is caused by iris bombe due to pupillary block with acute or subacute attack. It responds well to iridectomy or laser iridotomy. 3. Non-pupillary blocking: (7.8% of Chinese PACG). They usually have a deeper anterior chamber, and tend to be younger (below 40 years of age). Angle closure in this form of PACG is caused by: iris crowding mechanism or/and anteriorly positioned ciliary body against iris root to angle. It is critical to distinguish multi-mechanism PACG from other types. The initial treatment for this type of PACG is also iridectomy, but after the pupillary block component is eliminated by iridectomy, the residual non-pupillary blocking components should be highlighted by a diagnostic treatment procedure or by a ultrasound biomicroscopy (UBM) provocative test. Finally, the role of UBM in the observation and evaluation of the mechanism of angle closure is discussed and future research directions on PACG in Asians are proposed. Conclusion Chinese eyes have been recognized to be prone to the development of creeping angle closure. There is some direct evidence that creeping angle closure is caused by multiple mechanisms. Further study on this topic is needed. Chin Med J 2002; 115(11): 1706-1715