Clinical observation of 125I-labeled anti-alpha fetoprotein antibody radioimmunotherapy in hepatocellular carcinoma

AIM: To observe the therapeutic effects and toxic side effects of ¹²⁵I labeled horse anti-human alpha fetoprotein (AFP) polyclonal antibodies in immune targeted therapy against hepatocellular carcinoma (HCC).

METHODS: A modified chloramine-T method to produce nuclide ¹²⁵I labeled horse anti-human AFP polyclonal antibodies was used to treat 22 cases of HCC. Drugs were administered by intravenous drip. The median dose of ¹²⁵I in the whole group was 289.3 (100.3-708.9) MBq. In this series of 22 cases, 19 were evaluated. HCC cases of the same period treated by ¹³¹I anti AFP (A group), anti-cancer drugs and anti AFP conjugates (B group) and chemotherapy alone (C group) were used as controls.

RESULTS: The effective rate (CR + PR) was 31.6%, tumor shrinkage rate was 63.2% (12/19), AFP descending rate 64.7% (11/17) and 6 cases became AFP negative. The post treatment 1 year survival rate was 47.1% (8/17). Seven cases are still alive. Five cases survived 14.33 mo, showing good therapeutic tolerance and minimal toxic side effects.

CONCLUSION: The therapeutic effect in the treatment group was significantly better than that of the control groups. This may be due to the effect of the continuous radiation of the long half life ¹²⁵I within the tumor cells.

Co-regulative effects of the cAMP/PKA and DAG/PKC signal pathways on human gastric cancer cells during differentiation induced by traditional Chinese medicines

AIM: To evaluate the role of cAMP/PKA and DAG/PKC pathways of MGc80-3 cells treated with a traditional Chinese medicine compound, bailong preparation (bailong).

METHODS: cAMP level, DAG content and activities of PKA and PKC were measured in different groups: control; 1.8 g/L bailong; 1.8 g/L bailong + 20 mg/L PKA inhibitor; and 5 μmol/L PKC inhibitor.

RESULTS: When MGc80-3 cells were treated with bailong for 3 h, cAMP level and PKA activity were 113% and 19.7% higher than those of the control, while DAG content and PKC activity were 47.0% and 64.2% lower than those of the control. When the PKC pathway was blocked by PKC inhibitor GF-109203 X, cAMP level and PKA activity were increased by 78.8% and 33.5% compared to inhibitor GF-109203 X, and cAMP level and PKA activity were increased by 78.8% and 33.5% compared to the control, while the DAG content and PKC activity were decreased by 40.3% and 56.3%. When MGc80-3 cells were treated with bailong and PKA inhibitor blocked PKA pathways at the same time, cAMP level and PKA activity were decreased by 46.0% and 28.9%. On the other hand, DAG content and PKC activity were increased by 50.7% and 51.6% compared to the bailong group.

CONCLUSION: There is a relationship of cause and effect between differentiation of MGc80-3 cells and the signal pathways. The results of this study are similar to that of hexamethylenebisacetamide (HMBA), suggesting that the two signal systems are the foundation of proliferative regulation of MGc80-3 cells treated with Chinese medicine bailong or HMBA.

Studies on the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer

AIM: To study the relationship between the point mutation of ras oncogenes and the prognosis of patients with gastric cancer.

METHODS: The point mutations at codon 12 and 61 of c-Ha-ras, at codon 12 and 13 of K-ras, and at codon 12 of N-ras were studied with PCR-RFLP in 88 formalin fixed and paraffin embedded specimens of gastric cancer.

RESULTS: It was found that the overall rate of point mutation of ras oncogenes was 18.2% and the positivity of the point mutation of ras oncogenes was related to the cancerous invasion of the serosa, the status of lymph node metastasis, the stage of cancer and the survival time after surgery.

CONCLUSION: The findings suggest that the determination of point mutations of ras oncogenes can be used to determine the prognosis of patients with gastric cancer.

Sequencing of hepatitis C virus cDNA with polymerase chain reaction directed sequencing

AIM: To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome and establish a new sequencing method in China.

METHODS: Polymerase chain reaction (PCR) was combined with a DNA sequencing technique. PCR products were purified by agarose gel electrophoresis, polyacrylamide gel electrophoresis (PAGE) and polyethylene glycol (PEG) respectively. Then, in the presence of a 5’ labeling PCR primer, purified PCR products were directly sequenced. By this method, HCV NS5b cDNA from two HCV infected individuals (HC-42 and HC-49) were sequenced.

RESULTS: PCR directed sequencing worked best using PCR amplified DNA purified by electrophoresis as a sequencing template. When sequencing a large number of templates, the purification step can be bypassed by using a lower concentration of dNTPs (40 μmol of each dNTP) and primers (10 pmol of each primer) in the first stage of PCR. The aliquot of the first stage of PCR mixture was then directly used for amplification of chain terminated products but the sequencing ladders generated were of low intensity. Polyethylene glycol (PEG) could not remove nonspecific products of PCR, which affected the sequencing result to a certain extent and generated a background in sequencing ladders. Compared with the reported HCVJ and HC-C2, a new three nucleotide deletion was found in HC-42.

CONCLUSION: PCR directed sequencing is a rapid, simple and effective method, especially for sequencing large samples. A three nucleotide deletion was first reported.

Study of the influence of hiatus hernia on gastroesophageal reflux

AIM: To explore whether the presence of a sliding hiatus hernia influences gastroesophageal reflux.

METHODS: Endoscopy and 24 h pH monitoring were performed for 197 outpatients with gastroesophageal reflux symptoms.

RESULTS: Of the 197 patients with symptoms of gastroesophageal reflux, patients with hiatus hernia accounted for 36%. The incidence of esophagitis in patients with hiatus hernia was significantly higher than that in patients without hiatus hernia. The results of 24 h pH monitoring showed that 84 patients had physiological reflux, 37 had pathological reflux without esophagitis, 64 had reflux esophagitis and 12 had physiological reflux concomitant with esophagitis. All the patients with hiatus hernia had a longer percentage time with supine reflux and a higher frequency of episodes lasting over 5 min at night compared to those without hiatus hernia. The incidence of combined daytime and nocturnal reflux in patients with hiatus hernia was significantly higher than that in patients without hiatus hernia.

CONCLUSION: Pathological reflux and reflux esophagitis in some patients with symptoms of gastroesophageal reflux represent two different stages of gastroesophageal reflux disease. Pathological reflux is the first stage, in which the lower esophageal sphincter is incompetent but the esophageal mucosal resistance effectively prevents regurgitated acid from damaging the esophageal mucosa. Reflux esophagitis represents the second stage, in which the aggression of the regurgitated acid is so strong that the esophageal mucosa fails to resist it and the epithelium of the esophagus is damaged. Patients with hiatus hernia have a high incidence of combined daytime and nocturnal reflux, with the latter being responsible for esophagitis.

Effects of γ-interferon on hepatic fibrosis of schistosoma japonicum-infected mice

AIM: To probe the effect of γ-IFN on hepatic fibrosis in schistosomiasis japonica.

METHODS: The amount and distribution of γ-IFN and extracellular matrix in the liver of 60 S. japonicum infected mice and 30 healthy mice at different stages, and their dynamics in 20 infected mice after administration of recombinant γ-interferon were determined by immunohistochemical streptavidin biotin peroxidase complex method.

RESULTS: The amount of γ-IFN in liver peaked at the 16^th week after infection (3 mice respectively reached 2+, 3+ and 4+ grade), which was higher than the levels of infected mice at the 8^th-12^th week (P < 0.01), and γ-IFN was mostly distributed around egg granuloma. Fibronectin, laminin, type I and III collagens in liver of most infected mice reached 1+ grade and individual 2+ grade at the 8^th week after infection, which were higher than those of healthy controls (P < 0.01), and were linearly distributed around egg granuloma . With chronicity and decrease of γ-interferon, however, the matrix proteins and collagens gradually increased, peaked respectively at the 20^th and 24^th week (over 70% infected mice with 3+ to 4+ grade), became wide and thick, and deposited in band like or retiform shape around and in egg granuloma. After administration of γ-IFN, only 3 infected mice had 2+ grade of fibronectin at the 20^th week, and 2 mice had 3+ grade of type III collagen at the 24^th week, and none of them reached 4+ grade, which were significantly less than the untreated group at the same stage (P < 0.01-0.05).

CONCLUSION: γ-interferon may play an important role in opposing the inflammatory response of egg granuloma, decreasing secretion and deposition of extracellular matrix in the liver and suppressing hepatic fibrosis.

Reduced secretion of epidermal growth factor in duodenal ulcer patients with Helicobacter pylori infection

AIM: To investigate the concentration changes of epidermal growth factor (EGF) in duodenal ulcer patients with Helicobacter pylori (H. pylori) infection.

METHODS: Immunoreactive concentration of somatostatin, gastrin and epidermal growth factor of gastric and saliva juice in healthy volunteers, and chronic gastritis and duodenal ulcer patients with H. pylori infection were measured by radioimmunoassay.

RESULTS: Gastrin concentration of gastric juice in H. pylori-positive chronic gastritis (P > 0.05) and duodenal ulcer patients (P < 0.01) was higher than that of healthy volunteers (P < 0.05), whereas som atostatin concentration of gastric juice in chronic gastritis (P < 0.05) and duodenal ulcer patients (P < 0.01) was lower than that in healthy volunteers. Furthermore, EGF levels of gastric and saliva juice in duodenal ulcer patients with H. pylori infection (n = 10, 272.0 ng/L ± 96.3 ng/L and 8.3 ng/L ± 2.4 ng/L, respectively) were significantly lower than that in healthy volunteers (n = 12, 405.6 ng/L ± 35.6 ng/mL and 22.0 ng/L ± 17.0 ng/L, respectively) and in H. pylori-positive chronic gastritis patients (n = 25, 423.0 ng/L ± 104.0 ng/L and 22.0 ng/L ± 11.1 ng/L, respectively (P < 0.05).

CONCLUSION: A lower secretion of EGF may be a causative factor in the pathogenesis of H. pylori-positive duodenal ulcer.

Evaluation of a fecal occult blood test with reverse passive hemagglutination for colorectal neoplasm screening

AIM: To evaluate the one and three sampling reverse passive hemagglutination fecal occult blood test (RPHA FOBT) for colorectal neoplasm screening.

METHODS: A group of 3034 individuals with histories of colorectal polyps and/or ulcers were screened for colorectal cancer. Three day fecal samples were collected and 60 cm fiberoptic colonoscopy was conducted for each subject. The fecal samples were tested for occult blood with the RPHA method and the endoscopic and histopathological diagnoses were used as standard reference for evaluation. The sensitivity, specificity and positive and negative predictive values of different samplings were compared.

RESULTS: About 521 cases of colorectal neoplasms were detected, including 12 cases of colorectal cancer and 509 cases of polyps. Results showed that the mean sensitivity of one sampling RPHA FOBT for colorectal neoplasm was only 13.2%, the specificity was 90.3% and the positive and negative predictive values were 21.3% and 83.4%, respectively; while for the three sampling, taking one positivity as positive, the sensitivity increased to 22.0%, the specificity decreased to 81.6% and the positive and negative predictive values were 19.7% and 83.6%, respectively.

CONCLUSION: A single RPHA FOBT seems to be less sensitive for screening for colorectal neoplasms. Since it is convenient and economical, RPHA FOBT remains the most practical procedure for detection of early colorectal cancer and polyps if it is combined with other screening methods.

Surgical treatment of biliary ductal stricture complicating localized left hepatolithiasis

AIM: To summarize the experience in the clinical treatment of biliary duct strictures complicating localized left hepatolithiasis in the last two decades.

METHODS: A retrospective analysis of 67 cases of biliary duct strictures complicating localized left hepatolithiasis treated in our center in the last two decades was made with regards to each patient’s age, gender, results of various preoperative examinations, operative findings, treatment and postoperative courses.

RESULTS: The incidence of left hepatic duct (LHD) stricture was 59.8% and that of a left external hepatic duct (LEHD) stricture was 84.0 % and 84.8% respectively, in which a severe degree dominated. Among the operative procedures used in the treatment of LHD strictures, plastic operation plus biliary enteric anastomosis ranks first in frequency (52.2%), with a re-stricture rate of 17.1%. Left lobectomy ranks third (19.4%) with no re-stricture. Simple plastic performance or dilation had a high occurrence rate of re-stricture and usually needed subsequent surgery. Most LEHD strictures were eradicated by lateral segmentectomy or lobectomy, whereas most LMHD strictures were just the opposite. The rate of preoperative diagnosis of LMHD by endoscopic retrograde cholangiography, percutaneous transhepatic cholangiography, computed tomography or intraoperative and postoperative trans-T-tube cholangiography was much lower than that of LEHD or extrahepatic duct.

CONCLUSION: Too much attention paid to LEHD disorders in the treatment of localized left hepatolithiasis potentially results in negligence or omission in LMHD disorders. Malpractice treatments of LHD strictures are important factors affecting the long term results of localized left hepatolithiasis, for which left lobectomy is usually the therapy of choice.

Drinking water and liver cancer

AIM

To study the relationship between the mutagenicity of drinking water and incidence of liver cancer in high liver cancer incidence areas in Guangxi.

METHODS

A relationship between the mutagenicity of drinking water and incidence of liver cancer was studied in Fusui County, a high liver cancer incidence area in China. Thirty-two samples of different kinds of drinking water (13 samples of pond water, 3 samples of well water near the ponds, 5 samples of well water, 6 samples of river water and 5 samples of tap water) were tested with a micronuclear technique in the root tips of Vicia faba.

RESULTS

Among the 32 samples of different kinds of drinking water, 12 samples of pond water and 2 samples of well water near the ponds induced micronucleus frequencies on the root tips of Vicia faba to increase (P < 0.01), with the average micronucleus rate being 15.8% and 11.7%, respectively, while there was no difference between the micronucleus frequencies on the root tips of Vicia faba induced by well water (4.3%), river water (3.9%) or tap water (4.2%) and that on the control group (P > 0.05). Micronuclear effects on the root tips of Vicia faba in different kinds of drinking water were positively related to the incidence of liver cancer (r = 0.86, P < 0.05).

CONCLUSION

There were substances that caused chromosomal aberrations in the drinking pond water in high liver cancer incidence areas of Guangxi. Different kinds of drinking water were closely related to the incidence of liver cancer. Chemical mutagens in the water may be an important factor in the high incidence of human liver cancer.

Adherent properties of Helicobacter pylori to human epithelial cells

AIM: To study the properties and factors of Helicobacter pylori (H. pylori) adherence to human epithelial cells.

METHODS: The adherent properties of human epithelial cells were studied using a group of isolated H. pylori strains, anti-H. pylori monoclonal antibodies and varied pH environment in in vitro adherence model with HEp2 cells.

RESULTS: H. pylori YC 11A was able to adhere to HEp2 cells specifically and its adherence efficiency reached the highest (81%) within 3 h after incubation with HEp2 cells. There was no significant difference between adherence in air and in 5% oxygen. The monoclonal antibodies specific to H. pylori predominant antigens did not inhibit activities on adherence of H. pylori to HEp2 cells. The pH value significantly affected the adherence process and the optimal pH was 3.0-4.6.

CONCLUSION: H. pylori specifically adheres to HEp2 cells, and pH value significantly affects this process. A high level of anti-H. pylori predominant antibodies in serum may have no protective activities against H. pylori infection.

Study of the regulatory effect of acupuncture on rotation-induced gastric dysrhythmia in rabbits

AIM: A model of experimental gastric dysrhythmia in rabbits was set up to evaluate the effect of different acupoints on regulating gastric dysrhythmia in rabbits so as to promote acupuncture treatment for this kind of disease.

METHODS: A model of gastric dysrhythmia in rabbits was established by the rotation method using the basic electrical rhythm (BER) as an objective index. After puncturing at the points of Zusanli (ST36), Neiguan (PC6), Tiaokou (ST38) and Tianquan (PC2) in the four groups of experimental gastric dysrhythmia rabbits, the difference in regulatory effects on the disturbance and frequency of the gastric electric slow wave was observed.

RESULTS: Before needling at the specific acupoints Zusanli and Neiguan, the percentage of disturbance electric slow wave for the Zusanli and Neiguan groups was 57.0785 ± 10.644 and 55.5173 ± 6.0500, respectively; after such needling, the percentage was 43.7823 ± 10.1518 and 43.5147 ± 6.8983 for the Zusanli and Neiguan groups, respectively, while the frequency of electric slow wave for the Zusanli and Neiguan groups was 2.2870 ± 0.3800 and 2.4020 ± 0.3536, respectively, before needling and after needling, the frequency was 2.7090 ± 0.5865 and 2.9220 ± 0.4923 for the Zusanli and Neiguan groups, respectively. Comparing the percentage and frequency for the Zusanli and Neiguan groups before and after needling, the result shows that both groups have a significant difference statistically (P < 0.05) but between the Zusanli and Neiguan groups, there was no significant difference. Before and after needling the nonspecific acupoints of Tiaokou and Tianquan, there was no difference between the Tiaokou and Tianquan groups. Between the Zusanli and Tiaokou groups and the Neiguan and Tianquan groups, there are significant differences in regulating gastric dysrhythmia.

CONCLUSION: This model is suitable for the observation of gastric dysrhythmia. The specific acupoints of Zusanli and Neiguan have good effects on the treatment of gastric dysrhythmia.

Inhibitory effect of sulindac against chemically-induced primary colonic tumors by N-methyl-N-nitrosourea in mice

AIM: To investigate the chemopreventive effect of sulindac, a nonsteroidal anti-inflammatory drug (NSAID), on the growth of N-methyl-N-nitrosourea (MNU)-induced mouse colonic tumors.

METHODS: The experimental colonic tumor model induced by intrarectal instillation of MNU in mice was used in the present study. In the first experiment, MNU intrarectal was instilled and sulindac administered concurrently to a group of mice for a period of 18 wk, while a control group of animals received MNU only for the same period. In the second experiment, two groups of mice that had already been treated with MNU for 12 wk received sulindac or not for another 18 wk.

RESULTS: The tumors induced in mice were all located in the distal part of the large intestine. There were no significant differences in the location and the gross appearance of the tumors in the MNU-induced group and control group in both experiments. In the first experiment, sulindac caused a significant reduction in both the number of mice with colonic tumors and the number of tumors per mouse. Sulindac had a significant inhibitory effect on the growth of the MNU-induced tumors. However, in the second experiment, the inhibitory effect of sulindac was less or disappeared.

CONCLUSION: Sulindac has a protective effect against the chemical induction of colonic tumors by MNU in mice. The chemopreventive effect is more significant in the initial stage of the tumor, while in the promotion stage this effect is less or disappeared. Sulindac can not cause the regression of established tumors.

Cellular immune function and liver damage in post-hepatitic cirrhosis

AIM: To study cellular immune function in patients with post-hepatitic cirrhosis (PHC) and its relationship with different types of liver damage.

METHODS: Fifty-one patients with PHC, including 20 cases of Child-Pugh class A, 18 of class B, 13 of class C and 22 normal subjects as controls were studied. After peripheral blood mononuclear cells were isolated by Ficoll-Hypaque gradient centrifugation, lymphocyte transformation (LT) test, IL-2 activity and NK cell activity were measured by the ³H-TdR incorporation technique.

RESULTS: Changes of LT stimulation index (SI), IL-2 activity (SI) and NK cell activity (%) in patients with PHC were significantly decreased compared with in the healthy controls (18.1 ± 13.0 vs 34.9 ± 21.7, P < 0.01; 8.1 ± 6.0 vs 13.6 ± 5.8, P < 0.01; 40.3 ± 21.7 vs 61.3 ± 20.5, P < 0.01; respectively). The defects of cellular immune function were closely related to Child-Pugh classification. The values in class C were much lower than those in B and A (P < 0.01) and those in B were lower than those in A (P < 0.05).

CONCLUSION: Defective cellular immune functions in patients with PHC are connected with the degree of liver damage.

Uptake of bacterial lipopolysaccharide and expression of tumor necrosis factor-α-mRNA in isolated rat intrahepatic bile duct epithelial cells

AIM

To study the uptake of bacterial lipopolysaccharides (LPS) and expression of tumor necrosis factor α-mRNA (TNF-α-mRNA) with cultured rat intrahepatic bile duct epithelial cells.

METHODS

By using fluorescent, immunohistochemical and in situ hybridization techniques, the uptake of Escherichia coli LPS and expression of TNF-α-mRNA with isolated rat intrahepatic bile duct epithelial cells were observed with confocal laser scanning microscopy.

RESULTS

Positive reactions to LPS were found in the cytoplasm of isolated intrahepatic bile duct epithelial cells after incubation with LPS for 15 min and the FITC fluorescent intensity against LPS was significantly higher than that of the controls (121.45 μFI/μm(2) ± 15.62 μFI/μm(2) vs 32.12 μFI/μm(2) ± 9.64 μFI/μm(2), P < 0.01). After incubation with LPS for 3 h, fluorescein isocyanate (FITC) fluorescent intensities of the expression of TNF-α-mRNA with fluorescent in situ hybridization in the cytoplasm and nuclei of the cultured bile duct epithelial cells were significantly higher than those of the controls (189.15 μFI/μm(2) ± 21.33 μFI/μm(2) vs 10.00 μFI/μm(2) ± 8.99 μFI/μm(2), 64.85 μFI/μm(2) ± 14.99 μFI/μm(2) vs 21.20 μFI/μm(2) ± 2.04 μFI/μm(2), respectively (P < 0.01)). The increase of FITC fluorescent intensity of TNF-α-mRNA expression in the cytoplasm peaked at 6 h after incubation (221.38 μFI/μm(2) ± 22.99 μFI/μm(2)). At various time points after incubation with LPS, the increase of fluorescent intensities of TNF-α-mRNA in the cytoplasm were much higher than those in the nuclei (P < 0.01).

CONCLUSION

LPS can act on and enter into isolated intrahepatic bile duct epithelial cells and stimulate the expression of TNF-α-mRNA.

Construction of retroviral vector carrying HSV-tk gene under control of human AFP enhancer core sequence and human pgk promotor

AIM: To construct retroviral vector bringing HSV-tk gene under control of human AFP enhancer core sequence and human pgk promoter.

METHODS: Internal SV40 promoter was deleted by SalI from retroviral vector pMNSM to construct pMNM. HSV-tk gene driven by pgk promoter was released by BamH I from an eukaryotic expression vector pBPGK-tk, and inserted into polylinker site of pMNM to construct pMNP-tk retroviral vector. Human α-fetoprotein gene enhancer core sequence was released by EcoR I from pGEM. 7Z-AFPe plasmid was inserted into the immediate upstream of pgk promoter of pMNP-tk vector. Construction of hepatoma specific retroviral vector pMNAP-tk was completed.

RESULTS: The structure of pMNP-tk and pMNAP-tk vector was confirmed by restriction analysis.

CONCLUSION: The vector is of great significance for hepatoma specific prodrug transformation gene therapy.

Study on content of serum epidermal growth factor, gastric acid secretion and serum gastrin in duodenitis

AIM: To study whether there is EGF secreting abnormality in duodenitis and its relationship with gastric acid output and serum gastrin, so as to further explore the pathogenesis of duodenitis.

METHODS: Twenty-five duodenitis patients were confirmed by electrogastroscopy and biopsy, with an average age of 35.9 ± 7.0 years (range, 24-52 years). The control group consisted of 20 healthy volunteers (10 females, 10 males), with an average age of 34.4 ± 7.6 years (range, 23-48 years). Twenty duodenal ulcer patients (10 females, 10 males), with an average age of 35.0 ± 7.6 years (range, 24-52 years), were also included. Serum EGF and gastrin were measured using radioimmunoassay. Intragastric acidity was determined by pentagastrin method. Statistical analysis was performed using Student’s t-test.

RESULTS: In comparison with those in the control group, the contents of serum EGF and serum gastrin in duodenitis patients were all significantly increased. In comparison with those in the duodenal ulcer group, serum EGF was significantly increased, basal acid output and peak acid output were decreased, and serum gastrin was increased significantly in duodenitis patients. Serum EGF was negatively correlated with gastric acid output and positively correlated with serum gastrin.

CONCLUSION: In duodenitis, serum EGF concentration was increased, which was positively correlated with serum gastrin content, but was negatively correlated with gastric acid output. This indicates that EGF plays a protective role in the pathogenesis of duodenitis, which provides a new clue to pathogenesis study of duodenitis.

Therapeutic effects of rhubarb on gastrointestinal failure

AIM: To investigate the effects of rhubarb on gastrointestinal failure and the underlying pharmaceutical mechanism.

METHODS: Ninety-seven patients in intensive care unit were divided into a treatment group (76 critically ill patients complicated with gastrointestinal failure) and a control group (21 recovered patients). The effects of rhubarb on stress ulcer and toxic paralytic ileus in the patients were observed. The rectal and gastric intramural pH values, cardiac index, oxygen delivery, and oxygen consumption were measured.

RESULTS: Treatment with rhubarb achieved a significant curative effect in 30 of the 36 cases of stress ulcer complicated with gastrointestinal hemorrhage. Ha-2-receptor blocking agent had a poor effect on them (P < 0.05). Among the 49 cases of toxic paralytic ileus treated with rhubarb, peristalsis was recovered in 41, and gastrointestinal nutrition could be tolerated in 24, while other medicine had no effect on them. According to gastric and rectal intramural pH, rhubarb could improve gut mucosa perfusion. Among the 23 cases of multiple organ dysfunction syndrome who received treatment with rhubarb, 9 survived.

CONCLUSION: This study suggests that rhubarb has a good curative effect on gastrointestinal failure.

Correlation between Hepatitis delta virus infection and heptitis B virus serum markers

AIM: To analyse the correlation between HDV infection and HBV serum markers.

METHODS: Patients who were positive for HBV serum markers were selected and HDV infection was examined in them. Blood donors were used as a control group. Both HDV infection and HBV serum markers were tested by enzyme-linked immunosorbent assay.

RESULTS: HDV infection was detected in 40 of 289 patients who were positive for HBV serum markers. The overall positive rate of HDV infection was 13.8%. The positive rates of HDV infection in HBsAg(+) group, HBcAb(+) group and HBeAb(+) group were 17.6%, 18.8% and 25.2%, respectively, which were higher than that in HBeAg(+) group (10.9%), and none was detected in HBsAb(+) group. HDV infection appeared in HBsAg(+)HBcAb(+)HBeAb(+) patients with a positive rate of 26.2%, which was much higher than that in HBsAg(+)HBcAb(+)HBeAg(+) patients (10.9%).

CONCLUSION: HDV coinfection is more frequent in HBsAg(+) HBcAb(+)HBeAb(+) patients than in BsAg(+)HBcAb(+)HBeAg(+) patients. HDV infection is not completely related with the speed and amount of HBV replication.

Expression of metastasis suppressor gene nm23 in human hepatocellular carcinoma

AIM: To investigate the relationship between the expression of nm23-Hi mRNA and the metastatic potential of hepatocellular carcinoma (HCC).

METHODS: The expression of nm23-H1 mRNA was detected in 24 cases of HCC by in situ hybridization using digoxigenin-labeled nm23-H1 antisense cRNA probe. Twenty-four HCC specimens were divided into two groups according to the following criteria: (1) metastasis in portal lymph nodes; (2) the number of tumors in the liver; (3) cancerous emboli in the portal vein; and (4) the existence of satellite lesions. We named those meeting criteria (1) or (2) and (3), or (3) and (4) high metastatic potential (n = 6); and the others formed the low metastatic potential group (n = 18).

RESULTS: Positive results of in situ hybridization showed granules or masses in the cytoplasm. In the low metastatic potential group strong staining was obtained in ten specimens, while in the high metastatic potential group there was none. Three negative results were found in the high metastatic potential group, and one in the low metastatic potential group (P < 0.05). The expression of nm23-H1 mRNA was not correlated with some clinical factors, such as tumor size or the background liver disease.

CONCLUSION: The expression of nm23-H1 mRNA is inversely correlated with HCC metastatic potential, and can be considered as an index which indicates the metastatic potential of HCC.

Scanning electron microscopic study of lymphatic corrosion casts in the rabbit appendix

AIM: To study the three-dimensional structure and distribution of the lymphatics in the rabbit appendix, and to reveal the correlation between the perifollicular lymphatic sinus (PLS) and lymphatics.

METHODS: Freeze-fractured tissues and lymphatic corrosion cast with the Mercox were used for scanning electron microscopy (SEM), and histologic and semithin sections were used for light microscopy. The Mercox was diluted and injected intraparenchymally into the appendix wall. The injected appendixes were cut and put in a concentrated NaOH solution until the tissues were corroded away.

RESULTS: The lymphatic capillary networks were found in the superficial layer of the mucosa and the lymphatic capillary plexuses were observed in the deep layer of the mucosa. From the plexuses, the short grove-like lymphatic capillaries were connected with the PLS. The luminal side of the sinus looked like a flower basket. Short lymphatic capillaries arising from the bottom of the PLS were continuous with the lymphatics of the submucosa. The lymphatics of the submucosa were connected with the lymphatics running in the muscular layer, then they were led into the serosal lymphatics and drained into the lymphatics in the mesoappendix.

CONCLUSION: The PLS and rich lymphatics in the rabbit appendix may play an important role in the drainage of lymph and the immune function.

Changes of neurotensin and endotoxin in rats with intestinal ischemia

AIM: To investigate the changes of neurotensin (NT) and endotoxin in rats with segmental intestinal ischemia.

METHODS: The distal ileal mesenteric arteries in rats were ligated to make segmental intestinal ischemia models. At the 2^nd, 6^th and 12^th hours after intestinal ischemia, endotoxin levels in portal blood were tested by limulus lysate test and NT levels in plasma from the heart and in intestine tissues (ischemia and peri-ischemia areas) were assayed by radioimmunoassay. Histological changes of the mucosa were examined under light and electron microscopes.

RESULTS: NT levels decreased significantly in intestinal ischemia and peri-ischemia areas (34.07 ± 5.93 vs 40.14 ± 5.38, P < 0.05; 7.47 ± 1.38 vs 40.14 ± 5.38, P < 0.01), especially lower in ischemia area (34.07 ± 5.93 vs 7.47 ± 1.38, P < 0.05. However, NT level increased obviously in plasma (0.76 ± 0.16 vs 0.47 ± 0.10, P < 0.05). Levels of endotoxin elevated obviously in portal blood (389.0 ± 105.0 vs 55.1 ± 6.7, P < 0.01), and the mucosa was injured both in ischemia and peri-ischemia areas.

CONCLUSION: Intestinal ischemia injures intestinal mucosa and leads to decrease of intestinal NT level, which is accelerated by endotoxemia and increase of blood NT level.

Structure-activity relationship of pituitary adenylate cyclase activating polypeptide

AIM: To investigate the structure-activity relationship of pituitary adenylate cyclase activating polypeptide (PACAP) in guinea pig gallbladder using a synthetic PACAP/vasoactive intestinal peptide (VIP) hybrid.

METHODS: We synthesized PACAP-VIP hybrid peptides using the Fmoc strategy and a simultaneous multiple solid-phase peptide synthesizer. The peptides were tested in isolated guinea pig gallbladders using an improved horizontal type organ bath.

RESULTS: VIP induced relaxation of gallbladder smooth muscle strips, while PACAP27 contracted them. Amino acids at positions 4, 5, 9, and 24-26 were replaced without significant loss of activity. [Leu¹³]-PACAP27, a substitution in the α-helix domain, also had no significant loss in activity (P < 0.05). It was more potent than [Gly⁸]- and [DAsp⁸]-PACAP27 and could substitute peptides at position 21. Des-[His¹] and [Ala⁶]-PACAP27 had no activity at 10^-7 mol/L. [Gly⁸]-, [DAsp⁸]-, [Phe²¹]- and [Pro²¹]-PACAP27 at 10^-7 mol/L had about 25% of the activity of PACAP27 at 10^-7 mol/L (P < 0.05).

CONCLUSION: The N-terminal disordered region is more important than other regions for determining the physiological activity of PACAP in the guinea pig gallbladder.

Mucosal permeability to lipopolysaccharides in the colon in chronic alcoholic rats

AIM: To evaluate the effects of chronic alcohol abuse on the mucosal permeability to lipopolysaccharide in the colon in rats.

METHODS: Escherichia coli lipopolysaccharide (LPS, 20 μg/mL) was injected into the colon of chronic alcoholic rats (n = 10) and the rats were supplied with Lieber diets every other day for 6 weeks. Before LPS injection and 5, 10, 20, 30 min after injection, blood samples from the portal vein were obtained and contents of LPS in the blood were measured. The distribution of LPS in the colon tissues was observed with a confocal laser scanning microscope by immunofluorescent technique using a monoclonal antibody specific to the lipid A region of LPS. Normal rats were used as controls (n = 6).

RESULTS: Before LPS injection into the colon, LPS levels in the blood of portal vein of chronic alcoholic rats were significantly higher than those of normal controls (3.56 ± 0.67 pg/mLaa, vs 2.45 ± 0.15 pg/mLaa, P < 0.01). At 5, 10, 20, 30 min after injection of LPS, LPS contents were significantly higher than those before LPS injection (173.56 ± 23.45 pg/mLaa, 154.78 ± 20.57 pg/mLaa, 43.89 pg/mLaa ± 8.67 pg/mLaa, 45.38 ± 7.89 pg/mLaa vs 3.56 ± 0.67 pg/mLaa, P < 0.01 respectively). Most mucosal cells showed strong positive reactions to LPS in the rats of chronic alcohol abuse, but no significant changes of LPS contents in blood from the portal vein and fluorescentreactions to LPS in mucosal cells of normal rats were found after LPS injection.

CONCLUSION: Chronic alcohol abuse resulted in a significant increase of permeability to LPS in colon mucosal cells in rats.