2001年 · 第114卷第09期

Objective To study the urinary excretion of aquaporin-2 (AQP2) water channel protein, and the relationship between urine AQP2 concentration and renal AQP2 gene expression in chronic heart failure (CHF) rats. Methods Male Sprague-Dawley rats (200 g-250 g) underwent either a left coronary artery ligation, a model of CHF, or a sham-operation. Nine weeks after surgery, urinary AQP2 concentrations and renal AQP2 protein levels were measured by Western blot. Results The urinary concentration of AQP2 water channel protein increased significantly in CHF rats as compared with sham-operated rats (365.6% ± 102.9% vs 98.5% ± 47.6%, P < 0.01). There was positive correlation between urinary AQP2 concentration and renal AQP2 protein expression (r = 0.89, P < 0.01). Conclusion The urinary concentration of AQP2 water channel protein increases significantly in chronic heart failure rats. Chin Med J 2001; 114(9):899-901

Objective Laser-induced myocardial injury was investigated in a canine transmyocardial laser revascularization model. Methods A total of 23 channels were created in the left ventricles of 5 animals with a CO2 laser. Four animals were sacrificed immediately and one at week 2. Lactate dehydrogenase and succinate dehydrogenase in channel regions were examined with a Nitro-BT method staining. Results Immediately after the procedure, laser channels and surrounding injured myocardium could be stratified from the center to the border into 5 concentric zones, i.e.,vaporized zone, carbonized zone, enzyme-disappeared zone, enzyme-decreased zone and enzyme-concentrated zone. Two weeks later, the phenomenon disappeared. Conclusions Immediately after transmyocardial revascularization, there is a ring of enzyme-concentrated zone at the outermost region of injured myocardium. Two weeks later, enzyme activities of reversibly injured myocytes appear to have recovered. Chin Med J 2001; 114(9):902-905

Objective To analyze heart rate variability (HRV)and its changes with thyroxine treatment in patients with hypothyroidism. Methods HRV was analyzed using 24-hour electrocardiographic recording in 38 patients with hypothyroidism and 21 normal controls. The changes in HRV were evaluated for the 18 hypothyroid patients after 3 months of thyroxine therapy. Results The time domain measurements of HRV in hypothyroid patients were much lower than those in the control group. As to HRV frequency domain, the high frequency power was significantly higher, but the ratio of low frequency power to frequency power for hypothyroid patients was lower than in the controls. These abnormal changes of HRV measurements in hypothyroid patients were improved after treatment with thyroxine and were associated with recovery of serum concentrations of FT3 and FT4. Conclusions Patients with hypothyroidism often have autonomic neuropathies with a higher level of vagal tone. These abnormalities could be partly improved by thyoxine therapy. Chin Med J 2001; 114(9):906-908

Objectives To determine whether nuclear factor-κB (NF-κB) is activated in epithelial cells from children with asthma and to understand the role of NF-κB in airway inflammation in asthma. Methods Bronchial mucosa specimens were obtained from 9 children with asthma and 6 control subjects. NF-κB expression in epithelial cells were detected by immunohistochemical examination, and NF-κB-DNA binding was measured by electrophoretic mobility shift assay (EMSA). Results Nuclear expression of NF-κB in epithelial cells was observed in the 9 asthmatic children. F-κB-DNA binding was found in 4 asthmatic children (EMSA was performed in 6 asthmatic children). In contrast, both nuclear expression and NF-κB-DNA binding were absent in the 6 control subjects. Conclusion These results indicated that NF-κB is activated in epithelial cells from asthmatic children and the NF-κB activation may be the basis for the increased expression of many inflammatory genes and for airway inflammation in asthma. Chin Med J 2001; 114(9):909-911

Objective To choose one optimal extrinsic positive end-expiratory pressure (PEEPe) for ventilated patients with chronic obstructive pulmonary disease (COPD) and to compare two methods for choosing the optimal level of PEEPe. Methods Ten ventilated patients with COPD were included in the study. First, static intrinsic positive end-expiratory pressure (PEEPi, st) was measured when PEEPe was zero, and the PEEPi, st was called PEEPi, stz. PEEPe at 0%, 40%, 50%, 60%, 70%, 80%, 90% and 100% of PEEPi, stz, respectively, were applied randomly. Respiratory mechanics, hemodynamics, and oxygen dynamics were recorded 30 minutes after the level of PEEPe was changed. Results When PEEPe was not higher than 80% of PEEPi, stz, no measurement changed significantly. When PEEPe was increased to 90% and 100% of PEEPi, stz, PEEPi, st, peak inspiratory pressure, plateau pressure, pulmonary capillary wedge pressure and central venous pressure increased significantly, P < 0.01. Cardiac output and left ventricular work index decreased significantly, P < 0.01. Oxygen delivery decreased significantly, P < 0.05. When PEEPe was increased to 100% of PEEPi, stz, the right ventricular work index decreased significantly, P < 0.05. Conclusion Eighty percent of PEEPi, stz was the upper limit of PEEPe. The results of the two methods used to set the level of PEEPe were identical. Chin Med J 2001; 114(9):912-915

Objective To express mouse peroxisome proliferator activated receptor γ2 (mPPARγ2) in NIH3T3 fibroblasts mediated by the recombinant retrovirus and study its function. Methods The mPPARγ2 gene was subcloned into retrovirus vector pGCEN to generate the recombinant pGCEN/mPPARγ2. Then it was packaged into PA317 cells and selected with G418. Viral supernatants were harvested and then used to infect NIH3T3 fibroblasts. PPARγ activator 5, 8, 11, 14-eicosatetraynoic acid (ETYA) was used to induce the mPPARγ2-expressing NIH3T3 cells into adipocyte differentiation. Results The recombinant retrovirus pGCEN/mPPARγ2 was constructed, and the higher titers of the viral supernatants were obtained. mPPARγ2 was expressed in NIH3T3 cells mediated by the recombinant retrovirus. Lipid accumulation obviously existed in these induced adipocytes which morphologically resembled mature adipocytes in vivo and expressed tissue specific adipocyte P2 (AP2) and Leptin genes. Conclusions An adipocyte differentiation model in vitro was successfully established. The work is the basis for further research on the molecular mechanism of adipocyte differentiation induced by PPARγ2. Chin Med J 2001; 114(9):916-920

Objective To assess the effect of pharmacological and non-pharmacological interventions on Chinese subjects with impaired glucose tolerance (IGT). Methods In this 3-year prospective study, 321 subjects aged above 25 years with IGT were included. IGT was defined by 1985 WHO criteria utilizing a 75 g oral glucose tolerance test (OGTT). The subjects were divided into control (C), diet plus exercise (D + E), Acarbose (Glucobay, A) and Metformin (M) groups. The subjects in the group D + E underwent an individually designed diet and exercise program, the importance of which was reiterated annually. The group C only received conventional education on diabetes prevention. The two pharmacological groups were orally given Acarbose (50 mg, t.i.d) and Metformin (0.25 g, t.i.d), respectively. OGTT, weight, height, blood pressure and lipids were measured yearly during the follow-up. The t test, Chi-square test and proportional hazard regression analysis were used to analyze the risk reduction in diabetes conversion from each group. Results The baseline data of 4 groups had no statistical differences. By the end of study, both the fasting plasma glucose (EPG) and the 2 h postprandial plasma glucose (2hPG) in group C elevated (FPG from 6.02 mmol/L to 6.59 mmol/L, 2hPG from 8.83 mmol/L to 9.13 mmol/L), and the annual diabetes incidence was 11.6%. The corresponding changes in group D + E were FPG from 6.11 mmol/1 to 6.21 mmol/L, 2hPG from 9.28 mmol/L to 8.98 mmol/L, and 8.2% of annual diabetes incidence. In contrast, both the FPG and the 2hPG significantly decreased in group A (FPG from 6.03 mmol/L to 5.47 mmol/L, 2hPG from 8.24 mmol/L to 7.21 mmol/L) and in group M (FPG from 6.01 mmol/L to 5.85 mmol/L, 2hPG from 9.05 mmol/L to 7.92 mmol/L). The annual diabetes incidence decreased to 2.0% in group A, and 4.1% in group M. Proportional hazard regression analysis showed that the annual diabetes incidence was positively correlated with the baseline 2hPG and body mass index (OR =1.33, P = 0.006 and OR = 1.11, P = 0.008, respectively), and negatively correlated with group C and group M (OR = 0.12, P = 0.0001 and OR = 0.23. P = 0.0002, respectively). Conclusion The natural diabetes incidence is 11.6% in IGT population, and 8.2% in population with conventional diet and exercise interventions. There is no significant difference between them. The pharmacological interventions with Acarbose or Metformin significantly decrease diabetes incidence of IGT population. Chin J Endocrinol Metab 2001; 17: 131-134.

Objective To investigate the relationship between the expression of Th1/Th2 type cytokines and the effect of interferon-α therapy. Methods Th1/Th2 type cytokines were assayed by enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR) on 23 patients with chronic hepatitis B who were treated with interferon-α. Results Levels of IFN-γ in the supernatant of peripheral blood mononuclear cells (PBMC) cultures from the patients with hepatitis B were slightly lower than those of controls (P = 0.07). However, the levels of IL-4 were higher than those of controls (P = 0.01). Cytokines measurements during IFN-α treatment showed a trend to decreaseing levels of IL-4 at 4, 12, and 24 weeks. Levels of IFN-γ were slightly increased following IFN-α treatment (P = 0.09). In patients with a complete response to IFN-α, the levels of IFN-γ were higher at 24 weeks following IFN-α treatment than that of pre-treatment (P = 0.04), and the levels of IL-4 decreased markedly at 12 and 24 weeks (P = 0.02, 0.03, respectively). mRNA expression positively correlated with the level of Th1/Th2 type cytokines in the supernatant. Conclusion The expression of Th2 type cytokines is predominant in patients with chronic hepatitis B. Interferon-α therapy can modulate the balance of Th1/Th2 type cytokines, and this is related to its clinical effect. Levels of Th1/Th2 type cytokines could be a predictor of clinical response during Interferon-α treatment. Chin Med J 2001; 114(9):921-924

Objective To determine whether treatment with Gliclazide (Diamicron) is able to prevent development of microvascular complications in type 2 diabetes mellitus. Methods This trial was carried out in seven centers of the National Diabetes Mellitus Collaborative Study Group. Two hundred and eighty-five patients with type 2 diabetes mellitus were recruited from six areas of China and divided into Gliclazide group (n = 155) and Glibenclamide group (n = 130). Age, sex, duration of diabetes and body mass index were recorded at entry. Fasting and 2 h postprandial blood glucose were measured monthly while HbAlc was determined at a 3-month interval. Retinal photography and fluorescein angiography were performed in the 1st and 3rd year. Results There were no significant differences in age, sex, blood pressure, duration of diabetes, mean blood glucose and HbA1c between the Gliclazide and Glibenclamide groups at baseline, in the 2nd and 3rd follow-up year. There were no significant differences in retinopathy between the two groups at baseline, but at the end of the 3rd year, the subjects in Gliclazide group with retinopathy progression over one grade were significantly less than those in Glibenclamide group (2.58% vs 18.46%, P < 0.0001). Logistic stepwise-regression analysis showed that treatment with Gliclazide had an independently negative correlation with development of retinopathy. The same analysis procedure showed that treatment with Gliclazide had an independently negative correlation with the slight increase (≥20 μg/min) of urine microalbumin excretion. Conclusion Gliclazide shows a specific effects on retarding the progression of retinopathy and the slight development of urine microalbumin, which is independent of age, duration of diabetes, control tightness of blood glucose and blood pressure. Chin J Endocrinol Metab 2001; 17: 144-147.

Objective To investigate the sequence and characteristics of expression of proto-oncogenes, c-fos, c-myc and endogenous basic fibroblast growth factor (bFGF), in burn tissue from rats. Methods A partial thickness burn of 30% TBSA was created on the backs of Wistar rats. Immunohistochemistry was used to detect the expression of these proteins in normal and burned skin at 3 hours, 6 hours, 1 day, 3 days, 7 days and 14 days postburn. Results Expression of c-fos, c-myc and bFGF was induced by the burn, but these three proteins showed different expression levels in sequence and distribution. Expression of c-fos increased and peaked at 3 hours postburn. Stain positive granules were distributed mainly in the cytoplasm of basal cells and the nuclei of fibroblasts. The expression of bFGF protein increased at 6 hours and peaked at 1 day postburn; it was distributed in the cytoplasm of fibroblasts. c-myc protein peaked at 3 days postburn and was also distributed in the cytoplasm of fibroblasts. Conclusions Thermal injury can induce c-fos, c-myc and bFGF expression and show phasic control and regional distribution. The phasic expression of these three proteins indicates that there maybe a regulatory relationship between proto-oncogenes and growth factors in early burn. This may play an important role in late tissue repair. Chin Med J 2001; 114(9):925-928

Objective To assess the relationship between apolipoprotein E (apoE) polymorphism and the early onset of coronary heart disease (CHD) and the effect of apoE on lipids and lipoproteins in healthy Chinese subjects. Methods Sixty-eight patients with CHD younger than 55 years (CHD1), 136 patients with CHD older than 65 years (CHD2), and 136 healthy subjects were enrolled, and their plasma levels of triglyceride (TG), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) were determined. The apoE genotypes were identified by polymerase chain reaction-restriction fragment length polymorphism. Results apoE 3/4 genotype and E4 allele frequency in the CHD1 group were higher than those in the CHD2 group and healthy subjects, while no differences were found between CHD2 and healthy subjects. Meanwhile, the plasma levels of TC and low density lipoprotein cholesterol (LDL-C) were higher in the CHD2 group than in both CHD1 group and healthy subjects. Each apoE isoprotein has variable TC and LDL-C levels that is E2 (E2/2 + E2/3) < E3(E3/3) < E4(E4/4 + E3/4). Conclusion apoE is one of the genetic factors that affect TC and LDL-C levels, and apoE 4 has a very close relation to CHD, suggesting that apoE 4 is an independent genetic factor of the early onset of CHD. Chin Med J 2001; 114(9):983-985

Objective To compare the advantages and disadvantages of two procedures: Roux-Y with enterostomy and Roux-Y with spur valve in the treatment of biliary atresia. Methods Twenty-four patients with biliary atresia underwent hepatic portoenterostomy with percutaneous jejunal enterostomy (Group A) and 24 patients underwent Roux-Y with antireflux spur valve (Group B). Clinical data were reviewed retrospectively. Results Ten patients remained alive in the Group A. Among them, 9 survived without jaundice, the oldest one being 9-years old. One of the 9 patients had portal hypertension. The remaining one who survived with jaundice and portal hypertension was 8-years old at follow up. Ten patients in the Group B remained alive. Of them, 8 survived without jaundice and 2 with jaundice. Conclusions Two surgical procedures had similar effects in preventing reflux cholangitis, while spur valve has the benefit of quitting cutaneous enterostomy. Chin Med J 2001; 114(9):986-987

Objective To investigate the role of growth hormone-insulin-like growth factor I (IGF-I) axis in normal pregnancy. Methods Totally, 116 normal pregnant women were recruited from January 1997 to June 1998, with 20 normal nonpregnant women as controls. Maternal growth hormone (GH) and IGF-I concentrations were assayed by RIA and enzyme-linked immunosorbent assay, respectively. Results Maternal serum levels of GH increased throughout gestation, reached a peak at 25 weeks of pregnancy and remained fairly high (χ2 = 40.458, P < 0.0001). There was a significant difference between samples at 5-9 week gestational age and the controls (3.45 μg/L vs 1.61 μg/L, P < 0.05). The maternal serum levels of IGF-I increased rapidly throughout gestation from 29-week gestation and reached a peak of 188.86 μg/L at term delivery (χ2 = 50.224, P < 0.0001). Conclusions Maternal GH levels increased progressively throughout gestation, which correlated with fetal growth. Maternal GH may regulate nutrition supply among mother, placenta and the fetus and play an important role in transporting nutritional substrates by the placenta. The maternal IGF-I in the third trimester may promote fetal growth and placental functions. Chin Med J 2001; 114(9):988-990

Objective To evaluate the predictive value of serum neopterin for multiple organ dysfunction syndrome (MODS) in extensively burned patients. Methods Twenty-nine burn patients with TBSA of more than 70% were included in this study, and these patients were divided into two groups according to the occurrence of MODS. Blood samples were obtained on l, 3, 7, 14, 21 and 28 postburn days (PBDs). And serum neopterin levels were determined by radioimmunoassay. To evaluate the predictive power of neopterin, sensitivity, specificity, predictive value of a positive/negative test were calculated for the diagnosis of MODS. Results Serum neopterin levels in MODS group were significantly higher than those in non-MODS group on 3, 7, 14 and 21 PBDs (P < 0.05 - 0.01). And a positive correlation was found between neopterin levels and MODS scores in patients who developed MODS on 3, 7 and 21 PBDs (r=0.470-0.811). In a period of up to 28 PBDs, neopterin levels exceeding 35.0 nmol/L were associated with MODS by a clinical sensitivity of 81.1%, a specificity of 89.9%, a positive predictive value of 81.1%, and a negative predictive value of 89.9%. Conclusion These data indicated that the presence of constant high neopterin serum levels appear to be associated with the development of postburn MODS. Serum levels of neopterin might be a useful marker for the early identification of extensive burned patients at risk for MODS. Chin J Burns 2001; 17: 142-145.

Objective To investigate the mechanisms of Mal gene down-regulated in human esophageal cancer. Methods We amplified the 5' regulatory region of Mal gene in normal placenta tissue and human esophageal cancer cell lines EC9706, EC8712 and EC109 by optimizing the PCR methods, cloned and sequenced the PCR products and compared the sequence. Results Human esophageal cancer cell lines EC9706, EC8712 and EC109 had the 654 th of 5' regulatory region of Mal gene T to C changes, corresponding codon changed from TCC to CCC, and the amino acid which it codes changed from serine to proline; EC9706 also had the 657 th of 5' regulatory region of Mal gene T to C changes, corresponding codon changed from TGC to CGC, the amino acid which it codes changed from cysteine to arginine; EC8712 had the 139 th of 5' regulatory region of Mal gene A to G changes, corresponding codon changed from GGA to GGG, the amino acid which it codes remained glycine. Conclusion Our results suggest that there are many point mutations in 5' region of Mal gene in human esophageal cancer. Chin J Dig 2001; 21: 271-273.