Volume 113 · Issue 04 · 2000

Objective To compare the feasibility, complications, mid- and long-term advantages of peripherally inserted central venous catheters (PICC) and traditional central venous catheter (CVC) access assisted with X-ray image. Methods From 1997 to 1998, we conducted a study including 60 patients placed PICC lines and 60 patients placed CVC lines. Study variables included tip sites and complication rates. Results The result of the study asssisted with X-ray image showed that 95% of total PICC placements was successful in surgical patients. The mean duration for PICC catheters placed before removal was 13 days (6-98 days) and fifty-three catheters (88.3%) were removed following completion of therapy. The total occlusion rate was 6.7% (4/60), and occlusion rate in 3 Fr (20-gauge) catheters (3/20, 15%) was higher than in 4 Fr (18-gauge) catheters (1/20, 5%). Phlebitis occurred in 5% of patients(3/60) and one catheter fracture happened on the catheter-hub junction (1.7%). The catheter tip dislocation occurred in 3 cases with PICC (3/60, 5%) and was moved to the optional position asssisted with X-ray image. In CVC group, the total successful placement was 88% and the mean duration was 14 days (7-104 days). Pneumothorax happened in 1 case (1.7%). The catheters were withdrawn in 4 catheter dislocation cases. No catheter-related sepsis and hemopneumothorax happened in both two groups. Conclusions PICC assisted with X-ray image has advantages of less trauma and accurate localization, which could avoided many severe complications of central venous access such as pnemothorax. The new method provides a reliable and effective venous access that could satisfy mid-and long-term treatment in the patients receiving a variety of solutions, primarily parenteral nutrition, chemotherapy or antibiotic infusion.

Objective Along with the development of gastric acid assays, 24-hour intragastric pH monitoring has become an important method in the study on physiologic secretion of gastric juice. To study the influence of age on 24-hour intragastric pH rhythm, the effect of different ages on circadian patterns of intragastric pH rhythm, the effect of different ages on circadian patterns of intragastric pH was studied using 24-hour pH monitoring. Methods Eighty asymptomatic volunteers, including 51 aged 60 - 82 (average 71 years) and 29 at 18-28 (average 21 years) were chosen after thoroughly screening by medical history, physical examination, blood biochemical assays and gastro-endoscopy showing no mucosal erosion nor peptic ulcer. Chronic superficial gastritis was, however, diagnosed in 16 and chronic atypical gastritis of gastric antrum in 35 of the elderly subjects endoscopically. Thirty two patients, 20 younger aged 21 - 53, average 35 years and 12 elderly seen under the endoscopy showed active duodenal ulcer (DU) but had not been treated with anti-ulcer drugs before pH monitoring. Gastric pH was measured using monocrystal antimony electrode (MK Ⅲ by CTD Co., Sweden). The electrode was placed at 5 - 7 cm below the lower border of manometrically identified LES. The 24-hour pH values were processed to obtain: baseline pH, 24-hour median pH, 24-hour mean pH, 24-hour plateau pH, median pH at night (21:00-7:00), and mean pH at night (21:00 - 7:00). Results There was no significant difference in the level of median pH (1.82 vs 1.44), baseline pH (1.09 vs 1.21) between the elderly and non-elderly groups. But the value of prandial plateau pH was higher in the elderly group than that in the non-elderly group (4.36 vs 3.14, P < 0.05). Compared with 29 non-elderly asymptomatic subjects, 45 elderly subjects (88.2%) had the similar level of 24-hour median pH. The value of median pH at night in elderly patients with DU was lower than that in asymptomatic elderly subjects (2.15 vs 1.17, P < 0.05). Patients with DU in different age groups had the similar values of 24-hour median pH and median pH at night. Conclusion The age factor dose not influence the activity of intragastric hydrogen ion at fasting state.

Objective To investigate the mechanism of lipid-lowering effect of the Astragalus mongholicus and Angelica sinensis compound (A&amp;A) on nephrotic hyperlipidemia in rats. Methods Rats with nephrotic syndrome from accelerated nephrotoxic serum nephritis were used. They were divided into two groups: A&amp;A treatment group and nephrotic control group. Normal rats were used as a normal control group. Serum lipids, serum lipoprotein lipase (LPL) and lecithin-cholesterol acyltransferase (LCAT) were assayed biochemically and enzymatically. mRNAs of hepatic hydroxy-methyl glutaryl-CoA reductase (HMG-CoA-R) and low-density lipoprotein receptor (LDL-R) were assessed by Northern blot. Results In nephrotic control group hyperlipidemia was found. The activities of serum LPL and LCAT were low. Hepatic HMG-CoA-R mRNA increased temporarily at the early stage while LDL-R mRNA decreased gradually. In A&amp;A treatment group, serum total cholesterol (TC), triglyceride (TG), low-density lipoproteins (LDL) and very low-density lipoproteins (VLDL) were significantly lower than those in nephrotic control group. There was no change in the amount of hepatic HMG-CoA-R mRNA, but hepatic LDL-R mRNA and activities of serum LPL and LCAT increased significantly. Conclusions A&amp;A alleviates hyperlipidemia considerably in nephrotic rats. A&amp;A improves disorders of lipid metabolism perhaps through up-regulating the expression of hepatic LDL-R gene and through increasing the activities of serum LPL and LCAT. Chin Med J 2000; 113(4): 310-314

Objective To investigate the effect of lipopoly-saccharide(LPS) and dialyzer membrane on cytokine gene expression and protein production in uremic patients on continuous ambulatory peritoneal dialysis (CAPD) and regular hemodialysis(HD). Methods Interleukin-1β (IL-1β) and interleukin-1 receptor antagonist (IL-1Ra) produced by cultured peripheral blood mononuclear cells (PBMC) after exposure to cuprammonium (Cup) membrane, polysulfone (PS) membranes or endotoxin were detected using enzyme-linked immunoabsorbent assay. mRNA expression was determined simultaneously by in situ hybridiztion. Results In the absence of endotoxin, a small amount of IL-1β and IL-1Ra was produced by PBMC harvested from HD and CAPD patients after incubation with Cup or PS during subsequent 24-hour culture. For healthy controls, IL-1β was barely detectable just above the detection limit. Although no differences could be found in protein synthesis between Cup and PS, in situ hybridization showed that Cup induced markedly higher level mRNA coding for IL-1β and IL-1Ra. In contrast, when subsequently stimulated with endotoxin, PBMC incubated with Cup could produce significantly larger amount of IL-1β and IL-1Ra compared with either unstimulated cells or post-incubation PBMC with PS. LPS-stimulated PBMC in healthy subjects produced similar amount of IL-1β and markedly lower IL-1 Ra as compared with uremic patients on HD and CAPD. Conclusions Two steps are required in healthy control for IL-1β and IL-1Ra production: induction of mRNA transcription by membrane contact, followed by LPS-induced translation, while in uremic patients on HD or CAPD bioincompatibility-membrane and LPS have a synergetic effect on IL-1β and IL-1 Ra production. There exists an unbalance between IL-1β and its specific inhibitor in maintenance dialysis patients. Chin Med J 2000; 113(4): 315-319

Objectives To evaluate the prevalence of embolic events and relevant factors in elderly Chinese patients with atrial fibrillation(AF), and to provide evidence on ways to prevent embolic events. Methods Autopsy data from ninety-three continous elderly Chinese patients with AF were analysed. The incidence of embolic events and its relationship to underlying disease, pathologic changes in the heart, and other clinical characteristics were examined. Results Embolism were observed in 27 of 93 cases, with an incidence of 29.03%. The incidence of embolic events was higher in elderly patients with rheumatic heart disease than those with coronary artery disease, hypertensive myocardiopathy and heart diseases. Patients with chronic AF, with a course of AF ≥ 3 years, and those with heart failure or diabetes had a higher incidence of embolic events than those without these complications. There was significant difference in incidence between paroxysmal and chronic AF. Patients with left atrial or ventricular enlargement, mural thrombosis in cardiac chambers, valvular calcification and valvular vegetation also had a higher incidence of embolic events. Oral dipyridamole (75 - 150 mg/d) or aspirin (50 - 150 mg/d) showed no definite effects in preventing embolism in some patients. Conclusions There was a high incidence of embolic events in elderly Chinese patients with AF. Anticoagulation therapy should be provided to the elderly patients with AF, especially to the patients with risk factors for embolism. Chin Med J 2000; 113(4): 320-323

Objective To investigate the secretive features of type Ⅲ collagen in restenosis of the stented coronary artery and the relationship between the expression of type Ⅲ collagen and vascular smooth muscle cells (VSMCs). Methods An animal model of restenosis was established by implanting oversized tantalum stents into the coronary arteries in 26 dogs. At the 7th, 14th and 28th days after implantation, the stented coronaries were harvested. Transmission electronic microscopy and immunohistochemistry were employed to investigate the features of type Ⅲ collagen secretion and VSMCs' phenotype. The expression of type Ⅲcollagen was quantified and compared for the three stages. Results Migration and proliferation of VSMCs were the main features at the 7th day after injury. At the 14th day, proliferation of VSMCs reached the peak while much more secretion of collagen was noticeable. VSMCs began to transform from the synthetic phenotype to the contractile phenotype at the 28th day, when a great quantity of collagen was also secreted. The quantity of secreted type Ⅲ collagen was greater at the 14th and 28th day than that at the 7th day (P < 0.05). The stain density of type Ⅲ collagen was positively correlated to neointimal thickness at both of 14th and 28th day. Conclusion The pathological bases of restenosis are variant in different period of restenosis formation. TypeⅢ collagen may play an important role in the late stage of restenosis after coronary stenting. Chin Med J 2000; 113 (4): 324-327

Objective To understand the effect of intravenous nitroglycerin (NTG) on hemodynamics in infants and small children with congestive heart failure secondary to congenital cardiac defect of left to right shunt. Methods Heart rate, blood pressure and total peripheral resistance were monitored continuously. Echocardiography was used to measure ejection fraction, fractional shortening, end-diastolic volume index of left ventricle, pulmonary capillary wedge pressure, pulmonary artery mean pressure and left ventricular wall stress before uhe use and during 0.5, 1.0, 1.5, 2.5, and 5.0 μg • kg-1 • min-1 dosages of nitroglycerin (NTG). Results There was no significant difference in the indexes of heart rate, blood pressure, ejection fraction and fractional shortening of left ventricle, stroke volume index, cardiac output index, end-diastolic volume index before the use and after the use of NTG. Pulmonary capillary wedge pressure decreased from 15.5 ± 2.3 mm Hg before the use of NTG to 14.3 ± 2.2 mm Hg after the use of 0.5 μg • kg-1 • min-1 NTG (P < 0.05), minimum to 12.3 ± 2.4 mm Hg; left ventricular wall stress Ⅰ, Ⅱ and Ⅲ decreased from 407 ± 65 dyn. cm_2.103, 166 ± 48 dyn • cm-2 • 103, 255 ± 52 dyn • cm-2•lO3 to 357 ± 75 dyn • cm-2 • 103, 136 ± 48 dyr·cm-2•lO3, 218 ± 52 dyn • cm-2 • 103 (P < 0.05), minimum to 321 ± 50 dyn • cm-2 • 103, 114 ± 42 dyn • cm-2 • 103, 187 ± 42 dyn • cm-2 • 103, respectively. Total peripheral resistance and pulmonary artery mean pressure were decreased when the dosage of intravenous NTG was increased to above 2.5 μg•kg-1·min-1 (P < 0.05). There was no statistical difference in the above indexes of the different dosages. Conclusion Congestive heart failure secondary to congenital cardiac defect of left to right shunt in infants and small children is the indication of using intravenous NTG which could improve hemodynamics. There was different selectivity in dosage between arterial and venous vasodilatation, and the change in hemodynamics was independent of dosage. The dosages of 0.5-1.0 μg•kg-1•min-1 NTG are recommended when the decrease of cardiac preload is the main point of therapy of heart failure. Chin Med J 2000; 113(4): 328-331

Objective To evaluate the safety and immunogenicity of lyophilized, live attenuated hepatitis A vaccine (H2 strain) in rhesus monkeys. Methods Nine adult rhesus monkeys were used as experimental animals. The rhesus monkeys without anti-HAV were divided randomly into the aqueous vaccination group (4 rhesus monkeys), the lyophilized vaccination group (3 rhesus monkeys), and the control group (2 rhesus monkeys). Monkeys were inoculated by intramuscular injection, with control monkeys being inoculated with Minimum Essential Medium Eagle (MEM). Following vaccination, the monkeys were observed for the development of diarrhoea and other adverse side-effects, such as changes in appetite, frequency of defaecation and stool consistency for seven days. At the weeks 2, 3, 4, 6, 8, 10 and 12 positnoculation, the peripheral blood was collected from all animals and assayed for anti-HAV and alanine aminotransferase (ALT) and aspartate aminotransferase (AST), at weeks 0, 4 and 8 postinocuation, needle-biopsy specimens were taken at weeks 0, 4, 8 and 12, all monkeys were sacrificed and tissue samples were taken from liver, lung, heart, kidney and brain for pathological examination at week 12. Results Animals were immunized with a dose of 7.0 logTCID50/ml which is stable after freeze-drying. During the 12-week observation, no animals showed abnormal elevations of liver enzymes (ALT and AST) and no change in appetite or activity. Two monkeys (one in the aqueous group and the other in lyophilized group) showed possible lesions at week 8. The lyophilized vaccine, in addition to eliciting an anti-HAV IgG response similar to aqueous vaccine (P > 0.05), also showed IgM anti-HAV response at week 2 which was not observed with aqueous vaccine. Conclusions These results demonstrate that lyophilized, live hepatitis A vaccine is safe and highly immunogenic in primates, supporting its further evaluation in human clinical studies. Chin Med J 2000; 113(4): 332-335

Objective To observe the development and progression of intestinal metaplasia (IM) in dog's stomach and expression of tumor-related proteins in gastric mucosa lesions. Methods IM animal model was induced in stomach of Beagle dog by combining treatment of oral administration of N-methyl-N'-nito-N-nitrosoguanidine (MNNG) and ranitidine (R) with X-ray irradiation to the target organ. Expression of APC, p53, K-ras and bcl-2 gene proteins in animal gastric mucosa lesions were determined with immunohistochemical method. Results IM animal model was successfully induced and the dynamic pathological changes were observed by means of this model. It was confirmed that the progression from normal epithelial cells to IM cells may require several stages, including superficial gastritis, chronic atrophic gastritis, slight focal IM and moderate or severe IM. Aberrant bcl-2 protein can be detected in the atrophic mucosa epithelium and the abnormal expression of APC, K-ras and bcl-2 can be found in IM of mucosa. Conclusions IM model in stomach of Beagle dog can be successfully induced by our method (MNNG + R + X-ray). The progression from normal to IM in dog resembles that of human being and the expression of tumor-related proteins (APC, bcl-2, K-ras) may play a role in the malignant transformation of IM. Chin Med J 2000; 113(4): 336-339

Objective To evaluate the association of apolipoprotein E (apoE) and presenilin-1 (PS-1) gene polymorphism with late-onset Alzheimer's disease (AD). Methods A case-control study was undertaken to detect the polymorphism of apoE and PS-1 by polymerase chain reaction and digestion with the endonucleases of BspL I, Hha I and BamH I. Results The frequencies of apoE ε3/4 genotype and ε4 allele in late-onset AD (n = 42) were significantly higher than those of age-matched controls (P < 0.05). The frequencies of the apoE intron 1 enhancer (IE1) G/G genotype and G allele in late-onset AD were also significantly higher than those in controls (P < 0.05). The frequencies of the PS-1 1/1 genotype but not the 1 allele in AD were significantly higher than those in controls (P < 0.05). The apoE ε4 allele was associated with a tripling of risk for late-onset AD compared with that with no ε4 allele (odds ratio: 2.932). Homozygosity of the G allele in IE1 and 1/1 genotype in PS-1 was associated with a doubling of risk for late-onset AD, and odds ratios were 2.223 and 2.066, respectively. When the apoE ε4 was controlled, the association between the IE1 G/G genotype AD was no longer statistically significant (P > 0.05). We sequenced the exon 4 of apoE in patients with late-onset AD, and found no other genetic polymorphism or mutation except for apoE ε4 and IE1 G alleles associated with AD. Conclusion apoE ε4 gene appears to be the strongest gene risk factor for late-onset AD and its apparent association between the IE1 G/G genotype and late-onset AD is a consequence of the association between the ε4 and IE1 G/G genotype. The PS-1/1 genotype is weakly associated with late-onset AD. Chin Med J 2000; 113(4): 340-344

Objective To understand the role of genetic factors in the occurrence of esophageal cancer (EC). Methods A genetic epidemiological survey of 132 039 subjects, one-tenth of the whole population of Yangquan city, Shanxi Province in Northern China, was conducted in 1994. A total of 228 families with at least one newly occurring EC patient in each family were matched with equal number of control families for a 1:1 case-control study. Results The heritability of esophageal cancer among first degree relatives was 52.6%, that among second degree relatives was 31.2%, and the weighted average heritability was 49.2%. The segregation ratio was 0.176 ± 0.033, significantly less than 0.25, suggesting a multifactorial inheritance or decreased penetrance of a major locus. EC patients in families did not fit the binominal distribution, suggesting evidently familial aggregation. The relative risks among the first degree relatives were 10.49 for males, 7.69 for females, and 9.17 for combined data. The attributive risks among first degree relatives were 62.13/100 000 for males, 99.94/100 000 for females and 75.15/100 000 for combined data. All of these figures were higher than 40.17/100 000, the average of general population of the city. Conclusion Genetic factors play an important role in the pathogenesis of esophageal cancer in this area.