Effects of tetrandrine and verapamil on fibroblastic growth and proliferation

AIM: To investigate the effect of tetrandrine (Tet) and verapamil (Ver) on liver fibrosis by evaluating their effects on the growth and proliferation of fibroblasts.

METHODS: Flow cytometry and imaging analysis were used to study the effects of combined and individual treatment of Tet and Ver on fibroblastic proliferation in vitro. Untreated control cells were used for comparison.

RESULTS: Compared to untreated fibroblasts, those treated with both Tet and Ver showed higher percentages of cells in the G₁ and G₂+M phase in the cell cycle of 3T6 fibroblasts (P < 0.01) and markedly elevated protein content, while those treated with Tet only showed significantly lower intracellular RNA content (1.5-2.0 μg, P < 0.01) and those treated with Ver only showed lower intracellular DNA content (15-20 μg, P < 0.01).

CONCLUSION: The inhibitory action of Tet and Ver on fibroblastic growth and proliferation might be responsible for the antifibrotic effects of these medications in liver fibrosis.

Short- and long-term effect of interferon therapy for chronic hepatitis C

AIM: To study the short and long-term effect of interferon therapy for chronic hepatitis C.

METHODS: Sixty-eight patients with chronic hepatitis C were treated with interferon (3 × 10⁶ IU, im/2 d, for a course of three months) with 1 to 5 courses of treatment and followed for 1.5 to 3 years after the therapy.

RESULTS: According to antiviral effect of interferon, 76.5% (52/68) of the cases had a complete response by the end of the first therapy course, while 20.6% (14/68) and 2.9% (2/68) had a partial response or non-response. Over a half of the patients with a complete response (27/52, 51.9%) relapsed within 6 to 10 mo after the first course. Of the original cohort, nineteen patients received two courses of therapy, while one patient received three and another three received five courses of therapy. The follow-up for these patients was between 1.5 to 3 years, at which time 29 (42.7%) of the patients sustained a complete response, with four of them having HCV RNA positive serum, while the others had either a partial (37/68, 2.9%) or non-response.

CONCLUSION: Interferon therapy had a high short-term complete response but a low long-term complete response in the treatment of chronic hepatitis C.

Immunohistochemical study of gastrin in colorectal carcinoma tissues and adjacent mucosa

AIM: To study gastrin expression in colorectal carcinoma tissues and adjacent mucosa and discuss the function of gastrin in colorectal carcinoma.

METHODS: Gastrin expression in colorectal carcinoma tissues and adjacent mucosa was examined in 58 cases using immunohistochemical and immunoelectron microscopy.

RESULTS: A total of 35.1% of colorectal carcinoma transitional mucosa (TM), 48.3% of nontypical dysplasia mucosa and 60.3% of carcinoma tissue were positive for gastrin expression (P < 0.05). Immunoelectron microscopy revealed that protein A gold (PAG) granules localized to different electron-dense secretory granules in carcinoma cells, the intercellular spaces, and the microvillar membrane surface.

CONCLUSION: Gastrin expression in colorectal carcinoma tissue and adjacent mucosa, and the release of gastrin by carcinoma may be an initiating factor in carcinoma occurrence and development. Positive gastrin expression in colorectal carcinoma tissues can serve as a differentiation marker.

Clinical and experimental study on therapeutic effect of Weixibaonizhuanwan on gastric precancerous lesions

AIM

To study the therapeutic effect of Weixibaonizhuanwan on gastric precancerous lesions.

METHODS

Thirty-six patients with gastric precancerous lesions were treated with Weixibaonizhuanwan for 3 mo. Thirteen (36.1%) patients presented with mild atrophic gastritis, 14 (38.9%) with moderate atrophic gastritis, and nine (25.0%) with severe atrophic gastritis. Twenty-two (61.1%) and 27 (75.0%) of the cases were accompanied by intestinal metaplasia (IM) and dysplasia (DYS), respectively. Twenty of the 36 patients were men and 16 were women, ranging from 30 to 67 years in age, with 61.1% of the patients being 40-59 years old. The duration of the disease in these patients ranged from 3 mo to 21 years, with 20 (55.6%) patients experiencing durations of the disease between 5 and 10 years. The clinical manifestations of the disease in these patients included fullness of the abdomen (31 cases), abdominalgia (27 cases), anorexia (30 cases), eructation (26 cases), pantothenic acid (6 cases), and loose stool (9 cases). Patients were treated with Weixibaonizhuanwan and symptom improvement, level of atrophy of the gastric mucosa, and IM and DYS progression were analyzed.

RESULTS

After a 3-mo treatment with Weixibaonizhuanwan, seven patients experienced recovery. The treatment was effective in 11 cases, improved symptoms in 13 cases, and was ineffective in five cases. The overall efficacy rate was 86.1%. In patients with mild atrophic gastritis (n = 13), 11 improved into superficial gastritis and two experienced no improvement. In 14 cases of moderate gastritis, four cases improved into superficial gastritis and seven turned into mild atrophic gastritis, with three patients experiencing no improvement. Among severe atrophic gastritis patients (n = 9), five improved into moderate atrophic gastritis after treatment and four experienced no improvement. The overall efficacy rate in chronic atrophic gastritis patients was 77.8%. Among 9 patients with IM, IM disappeared in six cases, whereas three cases showed no improvement after treatment. In cases with moderate IM (n = 10), IM disappeared in two, turned into mild IM in five, and showed no change in three. Out of four cases with IM, one case turned into moderate IM and three showed no change. The overall efficacy rate in IM patients was 63.6%. Out of 16 cases of mild DYS, DYS disappeared in 11, whereas five cases showed no change. Out of nine cases of moderate DYS, DYS disappeared in two and turned into mild DYS in five cases, with two patients experiencing no change after treatment. No improvement was observed in the two cases of severe DYS after treatment. The overall efficacy rate in DYS patients was 66.7%. After treatment, expression of carcinoembryonic antigen (CEA) and proliferating cell nuclear antigen (PCNA) in gastric mucosa significantly decreased (P < 0.01). Before treatment, cancer staging of these patients by positive CEA expression was I, II, III, and IV in 13, 12, 9, and 2 cases, respectively. After treatment, the number of cases per stage changed to 25, 7, 3, and 1, respectively. Similarly, before treatment, staging by positivity of PCNA expression was I, II, III, and IV in 16, 11, 10, and 4 cases, respectively, and changed to 21, 9, 5, and 1, respectively, after treatment.

CONCLUSION

The use of Weixibaonizhuanwan in the treatment of gastric precancerous lesions showed promising therapeutic effects in patients after 3-mo treatments.

Effect of muscarinic blocker on enhancing the action of fructus aurantii immaturus on intestinal myoelectric activity in dogs

AIM: To investigate the effect of fructus aurantii immaturus (FAI) on small intestinal electrical activity in dogs.

METHODS: The effect of FAI was observed using a computerized electrophysiological method with the migrating myoelectric complex as a criterion. Fasted, healthy, and conscious dogs were given 100% FAI concentrated solution by gastrostogavage, and as soon as the effect on small intestinal electrical activity appeared, atropine was injected intramuscularly.

RESULTS: The enhancing action of FAI was inhibited significantly by atropine, a cholinergic receptor antagonist. Both the number of spike bursts per cluster and the number of spikes per minute in phase II and III and the general cycle were decreased (P < 0.01), although the duration of phase II and the general cycle was prolonged.

CONCLUSION: The effect of FAI might be related to the muscarinic receptors.

Alterations in p53 expression and cell proliferation in esophageal epithelia among patients from geographical areas with high or low incidence of esophageal cancer

AIM: To study changes in p53 expression and cell proliferation in esophageal epithelia of subjects from high or low esophageal cancer incidence areas in Henan Province to understand their molecular basis.

METHODS: Esophageal endoscopic mucosa biopsies were acquired and histopathological examinations were performed on 220 subjects from high esophageal cancer incidence areas and 50 subjects from low incidence areas in Henan Province. Esophageal epithelia were diagnosed as normal, basal cell hyperplasia or dysplasia based on cell morphology and tissue structure. Immunohistochemistry avidin biotin peroxidase complex (ABC method) was performed to analyze alterations in p53 and proliferating cell nuclear antigen (PCNA) expression in normal epithelia and epithelia with different lesion severities. The numbers of p53-positive and PCNA-positive cells were counted.

RESULTS: p53- and PCNA-positive nuclei were present in esophageal epithelia from subjects from both high and low incidence areas. The number of PCNA-positive cells gradually increased with lesion severity for both the high and low incidence areas. The number of p53-positive cells was higher in high incidence areas compared to low incidence areas, and rapidly increased with lesion severity. p53 expression positively correlated with PCNA expression.

CONCLUSION: The number of both p53- and PCNA-positive cells increased with lesion severity. p53 expression was higher in subjects from high esophageal cancer incidence areas compared to those from low incidence areas. These results may shed light into the molecular basis for the geographical distribution of esophageal cancer.

Hepatitis C virus RNA detection in serum and peripheral blood mononuclear cells of patients with hepatitis C

AIM: To investigate the existence and clinical significance of hepatitis C virus (HCV) RNA in the serum and peripheral blood mononuclear cells (PBMC) of patients with hepatitis C.

METHODS: HCV RNA was detected by nested polymerase chain reaction (Nested PCR) in serum and in PBMC of 46 patients with acute hepatitis C (AHC) and in 42 patients with chronic hepatitis C (CHC).

RESULTS: The positive rate of HCV RNA in PBMC of patients with CHC was markedly higher than that of patients with AHC (P < 0.01). The positive rates of HCV RNA in serum of patients with AHC and CHC and in PBMC of patients with CHC were significantly higher than those of anti-HCV positive patients with normal alanine aminotransferase (ALT) levels (P < 0.01). HCV RNA was negative in the serum of two patients, but could be detected in PBMC. In 12 patients, anti HCV was negative while HCV RNA was positive in serum.

CONCLUSION: (1) detection of serum HCV RNA by nested PCR might be helpful in the early diagnosis of anti-HCV negative hepatitis C; (2) liver damage in patients with hepatitis C might be correlated with HCV-viremia; (3) infection of PBMC by HCV might play an important role in chronic liver damage in patients with HCV and in the chronicity of its clinical course; and (4) PBMC might be considered as a “reservoir” for HCV.

Preliminary study on the pathological model of Piyinxu in rats

AIM: To study the method of constructing a pathological model of Piyinxu (spleen-yin deficiency) using Sprague-Dawley rats and to make preliminary observations.

METHODS: Folium sennae (0.8 g) and tabellae thyroidei (80 mg) were given daily by stomach feeding to each rat for 12 d to establish the pathological model of Piyinxu. The activity of the rats and the characteristics of their stool were observed.

RESULTS: We observed not only the symptoms of Pixu, such as diarrhea, poor appetite, abdominal distention, weight loss, but also Yinxuneire (endogenous heat), such as increase in water drinking, nervousness, and restlessness. These symptoms were all different from that of the control group of Piyangxu (spleen-yang deficiency).

CONCLUSION: Combining folium sennae and tabellae thyroidei is an effective method for establishing a pathological model of Piyinxu.

Morphological analysis of lymph vessels and capillaries in gastric carcinoma

AIM: To investigate the morphology of lymph vessel capillaries in both human gastric carcinomas and their peritumoral tissues, as well as the relation of this morphology to lymphatic metastasis.

METHODS: The morphology and fine distribution of both lymph vessels and capillaries in and around the primary foci of gastric carcinoma were studied using the 5′Nase Alpase double staining method. The total amount of opened vessels and the opening rate of lymph vessels and capillaries were counted using a light microscope (100 × magnification), and the maximal luminal area, perimeter and diameter were measured using an image analysis technique.

RESULTS: Lymph vessels and capillaries displayed strong 5′Nase-positive staining (brown and dark brown), while blood vessels and capillaries revealed significant Alpase activity (blue). There were many lymph vessels, capillaries and solid strip-like tissues found in the gastric carcinoma samples analyzed. The total amount of lymphatics in the metastatic group (gastric carcinoma vs peritumoral tissue) and non-metastatic group was 26.9 ± 14.2 vs 10.4 ± 4.0, 11.4 ± 3.4 and 9.7 ± 3.2, P < 0.01, respectively. Their opening rates were 21.2 vs 47.5 and 40.4 vs 46.0, P < 0.01, respectively. Their maximal luminal areas were 1502.98 ± 1236.91 vs 5526.80 ± 4853.42; 1918.14 ± 2299.24 vs 3836.16 ± 3549.16; 5526.80 ± 4853.42 vs 3836.16 ± 3549.16, P < 0.05, their perimeters were 220.33 ± 130.25 vs 441.43 ± 276.51; 241.79 ± 171.13 vs 333.80 ± 199.66; 441.43 ± 276.51 vs 333.80 ± 199.60, P < 0.05, and their diameters were 28.80 ± 14.98 vs 59.39 ± 28.53; 25.37 ± 15.79 vs 46.22 ± 20.85; 59.39 ± 28.53 vs 46.22 ± 20.85, P < 0.05, respectively. In summary, the lymphatics found in gastric carcinoma samples from the metastatic group were significantly lower than those of the other groups.

CONCLUSION: There are newly formed lymph capillaries found in gastric carcinoma. Dilation of lymph capillaries may be related to edema found in peritumoral connective tissues. The observed lymph node metastases from gastric carcinoma occur through mature lymph capillaries that invade in and around primary gastric carcinoma foci.

Immunohistochemical detection of proliferating cell nuclear antigen in hepatocellular carcinoma

AIM: To investigate the expression levels of proliferating cell nuclear antigen (PCNA) and its correlation with the mitotic count, histological grade, and metastasis of human hepatocellular carcinoma (HCC).

METHODS: PCNA expression was detected immunohistochemically with PC10 monoclonal antibody for 80 cases of HCC. The PCNA labeling index (LI) was assessed by counting the positively-stained nuclei per 500 cells.

RESULTS: PCNA LI ranged from 1.8% to 91.4% (mean = 33.9%) in cancerous tissues, and was significantly related to the tumor size, histological grade, mitotic count and the metastases found in HCC samples.

CONCLUSION: HCC Proliferation activity, as defined by PCNA immunohistochemical analysis, is strongly correlated with tumor invasiveness. These findings hold potential prognostic value for HCC patients.

Analysis of lactate dehydrogenase activities and isoenzyme patterns in colorectal cancer tissues

AIM: To investigate the relationship between lactate dehydrogenase (LDH) activity or LDH isoenzyme patterns and the pathogenesis of colorectal cancer.

METHODS: Activities of tissue LDH and LDH isoenzyme patterns in 16 patients with colorectal cancer were assayed using spectrophotometric procedures and agarose gel electrophoresis, respectively.

RESULTS: The total and specific activities of LDH were significantly higher in colorectal cancer tissues than those in adjacent noncancerous tissues (P < 0.001). The LDH isoenzyme pattern was also different from that in the control. The percentage of LDH₅ doubled and the ratio of LDH₄ + LDH₅/LDH₁ + LDH₂ was 3.6 ± 1.4 in cancer tissue, significantly greater than in the control.

CONCLUSIONS: The increased LDH activity in colorectal cancer tissues resulted mainly from the increased LDH₅, suggesting that the alteration of LDH activity and isoenzyme patterns were related to the pathogenesis of colorectal cancer.

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.