Effects of combined use of diallyl disulfide and Nacetyl-cysteine on acetaminophen hepatotoxicity in beta-naphthoflavone pretreated mice

AIM:To assess the protective effect of diallyl disulfide (DADS) and its combined use with N-acetyl-cysteine (NAC) on acetaminophen (APAP) hepatotoxicity in C57BL/6N (B6) mice pretreated with beta-naphthoflavone (BNF).METHODS:B6 mice were divided into six groups and all compounds used were injected intraperitoneally. Except for control and APAP group (receiving APAP only), the other groups received an injection of APAP (350mg/kg) 48 hours after BNF (200mg/kg) and either of DADS (200mg/kg), or NAC (500mg/kg) or both DADS and NAC.DADS was given 2 hours before APAP and NAC was injected with APAP.The mean survival time was recorded and livers were examined histologically.Hepatic glutathione (GSH) levels and plasma ALT were also determined at different time points.To evaluate the effect of DADS or NAC on hepatic P450 induction by BNF,liver microsomes were prepared and 7-ethoxyresorufin O-dealkylase (ERD) activity was determined using spectrofluorometrical methods. In vitro effect of DADS or NAC on ERD activity was assayed by directly incubating microsomal suspension with DADS or NAC of different concentrations.RESULTS:APAP was not toxic to mice without BNF pretreatment, but caused severe liver necrosis and death of all BNF-treated mice in 4 hours. A sharp depletion of GSH (approximately 62% of its initial content at 2 hours and 67% at 4 hours) and a linear elevation of ALT levels (536.8 plus minus 29.5 Sigma units at 2 hours and 1302.5 plus minus74.9 at 4 hours) were observed.DADS and NAC given individually produced mild protection,resulting in prolonged survival,a slower decline of GSH level and a less steeper elevation of ALT level.All mice died eventually. Co-administration of DADS and NAC completely protected mice.GSH level in this group lowered by about 35% and 30% at 2 and 4 hours, and ALT was 126 plus minus 18 and 157.5 plus minus 36.6 Sigma units at 2 and 4 hours. ERD activity in BNF-treated mice was about 5 times that of the constitutive level determined in normal mice. Neither DADS nor NAC inhibited P450 1A1/1A2 induction as determined by their effect on the induction of ERD activity.In vitro assay indicates that DADS,but not NAC,was a potent inhibitor of ERD activity(IC(50) = 4.6&mgr;m).CONCLUSION:A combined use of both DADS and NAC produced full protection in BNF treated mice against APAP hepatotoxicity.The mechanism is that DADS inhibits P450 1A1/1A2 activity, but not induction, which substantially reduces production of NAPQI, while NAC enhances liver detoxifying capability via serving as a precursor of GSH and stimulating GSH synthesis.

Endotoxins enhance hepatocarcinogenesis induced by oral intake of thioacetamide in rats

AIM:To clarify whether endotoxin is of pathogenic importance for hepatocarcinogenesis,or the increased cancer risk results solely from the cirrhotic process.METHODS:The rat model of hepatoma was treated by the intake of 0.03% thioacetamide in drinking water for six months. During induction of hepatoma, rats were additionally treated with splenectomy and/or lipopolysaccharide administration.The liver nuclear DNA index and proliferation index were quantitatively analyzed by flow cytometry. Hepatic histology was examined with light and electron microscopes. Plasmic endotoxin concentration and gamma-glutamyl transpeptidase activity were measured, and hepatoma incidence was recorded.RESULTS: Thioacetamide induced cirrhosis and hepatoma in Wistar rats with histology or regenerative nodule, fibrosis and neoplastic foci were quite similar to the pathogenic process of human cirrhosis leading to hepatoma. In comparison with TAA controls (DNA index: 1.15 plus minus 0.21), exo-endotoxin increased the DNA index by 7.8% (1.24 plus minus0.25, P < 0.02) and hepatoma rate by 16.7. Splenectomy-induced enteric endotoxemia increased the DNA index by 25% (1.44plus minus0.15, P < 0.01) and hepatoma rate by 33%. A summation of the effects of these two factors increased the DNA index by 36% (P < 0.01)and hepatoma incidence by 50%, moreover, the level of endotoxemia showed a close relation with DNA index (r = 0.96, P < 0.01), as well as with the occurrence rate of hepatoma (r = 0.00, P < 0.01). Histological findings further verified such alterations.CONCLUSION:Lipopolysaccharide administration and/or splenectomy-induced enterogenic endotoxemia may enhance rat hepatocarcinogenesis induced by oral intake of thioacetamide.

Evaluation of various solutions for small bowel graft preservation

AIM:To elucidate the effect of various solutions for small bowel graft preservation in pigs under hypothermic storage.METHODS:The swine segmental small bowel graft was autotransplanted after it was preserved with lactated Ringer's (LR), Euro-Collins (EC), hyperosmolarity citrate adenine (HC-A) and WMO-1 solutions for 10,18 and 24 hours,respectively.The recipient survival rate, morphological structure, graft mucosal energy substances and Na( +) -K(+) ATPase activity were studied,and graft absorption was estimated with D-xylose absorption test.RESULTS:The morphological study of the grafts preserved with LR or HC-A solution for 10 hours or with EC and WMO-1 solution for 18 hours was normal 6days after operation. Mucosal ATP,total adenine nucleotides (TAN) contents and Na( +) -K(+)ATPase activity of the graft preserved with EC or WMO solution were higher than that of the graft preserved with LR or HC-A solution.Serum level of D-xylose was higher in EC and WMO-1 groups than in LR and HC-A groups when the graft was preserved for 24 hours.CONCLUSION:EC and WMO-1 solutions can preserve the swine small bowel up to 18 hours, which are superior to LR and HC-A solutions.

Significance of vascular endothelial growth factor messenger RNA expression in gastric cancer

AIM: To study VEGF mRNA expression in gastric carcinoma and to clarify the association of its expression with the clinicopathologic features of the disease.

METHODS: In situ hybridization (ISH) and histochemistry were used to examine and analyze the expression of VEGF mRNA and antigen, and microvessel count (MVC) in 28 cases of gastric carcinomatous tissue in combination with clinical materials.

RESULTS: Ninteen of 28 gastric carcinomas were positive for VEGF mRNA. VEGF mRNA was mainly expressed in malignant cells and not in normal epithelium of gastric mucosa. Its expression was further increased in tumor cells adjacent to tumor necrosis zones, where stromal cells expressed VEGF mRNA occasionally. There was a close correlation between MVC and VEGF mRNA positivity (P < 0.005). High VEGF mRNA levels were significantly associated with serosal invasion, lymph node metastasis and TNM staging ( P < 0.05, respectively).

CONCLUSION: VEGF mRNA expression is associated with tumor invasion and metastasis by stimulating angiogenesis in gastric carcinoma.

Simplified isolation and spheroidal aggregate culture of rat hepatocytes

AIM: To explore a simplified method for isolation of hepatocytes and establish a method of primary hepatocyte culture with more aggregates and longer persisence.

METHODS: Wistar rat hepatocytes were isolated by a single extracorporeal two-step perfusion method, and the cells were seeded on poly-HEMA coated flasks and cultured with hormonally defined medium and gentle shaking at regular intervals.

RESULTS: The total yield of isolating hepatocytes amounted to 10⁸ cells for each rat liver with the viability of more than 90% in all isolations. Under the nonadherent environments, the cells were found to attach to each other and form multicellular aggregates rapidly, and the aggregates became spheroidal shape after two days in culture. The morphologic characteristics and albumin synthetic function of the multicellular spheroidal aggregates can be maintained for one month.

CONCLUSION: The simple and reliable isolation as well as large scale and longer time culture of hepatocytes can be used for experiments in liver cell transplantation and bioartificial liver support system.

Arterial chemoembolization for hepatocellular carcinoma

AIM: To study the therapeutic effects of transcatheter arterial three-segment chemoembolization for hepatocellular carcinoma (HCC).

METHODS: According to the anatomy of vessels, the tumor capillary networks, muscular arterioles and feeding arteries were successively occluded using lipiodol ultra-fluid (LUF), sinobufagin microsphere (SBMs) and particles of gelatin sponge (PGS). In this series of 80 cases, therapeutic effects were evaluated in 76 cases.

RESULTS: There were 22 cases (28.9%) with partial response and 41 (53.9%) with minor response in the 76 evaluated patients. The 6-month, 1-year, 2-year and 3-year survival rates were 97.4%, 86.8%, 46.1% and 27.6% respectively.

CONCLUSION: This regimen was a rational chemoembolization method for HCC patients.

CCR5 gene expression in fulminant hepatitis and DTH in mice

AIMS: To isolate mouse CCR5 cDNA (muCCR5) and study its expression in vivo.

METHODS: Marathon PCR was used to isolate muCCR5 cDNA and two animal models were designed to investigate the gene expression in vivo, one was mouse fulminant hepatitis induced by Propionibacterium acnes (P.acnes) and the other was that with delayed type hypersensitivity reaction (DTH). A specific GST-NH2-terminus of muCCR5 fusion protein antibody F(ab’)2 was prepared and clarified. RT-PCR and immunohistochemical analysis were used to observe the expression level of CCR5 gene in mice.

RESULTS: A positive reaction of mouse macrophage was found in DTH but not expressed in P.acnes induced fulminant hepatitis by RT-PCR and immunohistochemical analysis.

CONCLUSION: This muCCR5 expression may be involved in an allergic processmediated by cellular immunity but not acute inflammatory reaction induced by P.acnes.

Induction of apoptosis of lymphocytes in rat mucosal immune system

AIM: To undergo apoptosis during negative and positive selection processes in rat mucosal immune system which are implicated in the pathogenesis of various mucosal diseases.

METHODS: Female Sprague-Dawley rats were given protein synthesis inhibitor, cycloheximide, intravenously or intraperitoneally, an apoptosis was recognized by morphological hallmark under light and electronmicroscopy, and the expression of proliferating cell nuclear antigen was visualized immunohistochemically.

RESULTS: The apoptosis of mucosal lymphocytes in the digestive tract, as well as in trachea, uterus and lacrimal gland was induced by cycloheximide ( > 1.0 mg·kg^-1 body weight), which were located mainly in lamina propria and germinal centers of lymphoid nodules. At the same time, a portion of crypt epithelial cells of proliferating zone in small and large intestine, and the epithelial cells in genital tract were also found to undergo apoptosis. Immunostainings showed that apoptotic cells expressed proliferating cell nuclear antigen.

CONCLUSION: Apoptosis of lymphocytes in mucosal immune system can be induced by cycloheximide. This model will facilitate the understanding of normal mucosal immune system and its role in the pathogenesis of related diseases such as inflammatory bowel diseases.

Tumor radioimmunoimaging of chimeric antibody in nude mice with hepatoma xenograft

AIM: To study the radioimmunoimaging (RAII) using the human/mouse chimeric Ab to evaluate its targeting activity in animal models.

METHODS: To chimeric Ab was labeled with ¹³¹I. RAII was performed at different intervals after injection of radio-labeled Abs in nude mice with human hepatoma xenograft, and tissue distribution of radioactivity was measured. Comparison was made in the chimeric Ab between the single segment Ab and previous murine mAb against HBxAg.

RESULTS: The experimental objects developed tumor-positive image after 2 days of radio-labeled Abs injection, and the peak accumulation of radioactivity fell on the 7th day. The tumor/liver ratioactivity of the chimeric Ab, single segment Ab, anti-HBx mAb, and the control group was 281 ± 0.21, 2.44 ± 0.16, 4.60 ± 0.19, and 0.96 ± 0.14, respectively.

CONCLUSION: The genetic engineering Abs have a considerable targeting activity which can be used as a novel humanized vector in the targeting treatment of liver cancer.

CEA and AFP expression in human hepatoma cells transfected with antisense IGF-I gene

AIM: To determine whether antisense insulin-like growth factor-I (IGF-I) gene can modulate CEA and AFP expression in human hepatoma cells (HepG2).

METHODS: Transfection of HepG2 cells was accomplished using Lipofectin reagent. Northern blot analysis confirmed the antisense IGF-I RNA of the transfected cells. CEA and AFP levels were measured using radioimmunoassay.

RESULTS: Human hepatoma cell lines (HepG2) were transfected with antisense IGF-I gene. Northern blot analysis confirmed that antisense IGF-I RNA was expressed in the transfected cells. The effect of antisense IGF-I gene on CEA and AFP expression was demonstrated by the fact that the CEA and AFP levels in the supernatant of transfected cell culture were significantly lower as compared with the parent cells, [CEA 7.0 μg/L ± 0.76 μg/L and 3.29 μg/L ± 1.80 μg/L (P < 0.05) and AFP 53.63 μg/L ± 6.02 μg/L and 9.0 μg/L ± 5.26 μg/L (P < 0.01), respectively].

CONCLUSION: The malignant potentiality of the transfected cells was partially suppressed.Antisense IGF-I gene can modulate the expression of CEA and AFP in human hepatoma cell lines (HepG2)

Bile acids in serum and bile of patients with cholesterol gallstone

AIM: To analyze serum bile acids and biliary lipids of patients with cholesterol gallstone(CS) and explore the relationship between deoxycholic acid (DCA) and CS disease.

METHODS: Analysis of bile acids in serum was done with gas-chromatography in two groups: CS group (n = 151) and control group (n = 256). Serum bile acids and biliary lipids were also studied in 90 matched samples.

RESULTS: The serum DCA was 0.955 μmol/L ± 0.078 μmol/L in CS group, which was more than that of control group (0.696 μmol/L ± 0.047 μmol/L), P < 0.01. The ratio of DCA/chenodeoxycholic acids (CDCA) was 1.76 ± 0.30 in CS group, about two times that in control group (0.92 ± 0.14). The mole percent of DCA in bile was positively related to cholesterol saturation index (CSI) (P < 0.01) and the mole percent of CDCA in bile negatively to CSI (P = 0.01). There was correlation between the mole percent of DCA, CDCA and cholic acid in bile and in serum.

CONCLUSION: It is suggested that DCA is lithogenic and the increased amount of DCA or the ratio of DCA/CDCA in serum may be one of the features of cholesterol gallstone patients.

Cloning of 3H11 mAb variable region gene and expression of 3H11 human-mouse chimeric light chain

AIM: To clone mouse anti-human gastric cancer mAb (3H11) variable genes and to construct 3H11 human-mouse chimericantibody.

METHODS: The entire VH and VL genes of anti-gastric cancer mAb 3H11 were cloned by RT-PCR method from 3H11 hybridoma cells, using 5’ primers for leader sequences. The 3H11 VL gene was then inserted into human-mouse chimeric light chain expression vector and transfected into murine Sp2/0 myeloma cells.

RESULTS: DNA sequence analysis indicated that the cloned genes included the whole leader sequences and the mature Ig variable region encoding sequences. Aftergene transfection, transient expression of chimeric light chain protein was detected.

CONCLUSION: DNA sequences and transient expression indicated that the cloned gene was functional. This work laid basis for constructing 3H11 human-mouse chimeric antibody in the future.

Expression of somatostatin mRNA in various differentiated types of gastric carcinoma

AIM: To investigate the expression of somatostatin mRNA in various differentiated types of gastric carcinoma.

METHODS: By using in situ hybridization and immunohistochemical techniques, the expression of somatostatin mRNA and somatostatin immunoreactivity in the normal gastric mucosa, the poorly, moderately and well-differentiated gastric carcinomas, and various clinical stages of carcinoma were observed.

RESULTS: In comparison with the normal gastric mucosa, the significantly increased expression of somatostatin mRNA positive cells was displayed in gastric carcinoma ( t = 2.681, P < 0.01). The positive signal cells were distributed in a scattered form or aggregated as a mass or a cord, and the positive cells were more significantly enhanced in poorly differentiated carcinomas than those in well and moderately differentiated carcinomas (t = 2.962, P < 0.01). The somatostatin mRNA hybridization signals in stages III and IV of gastric carcinoma were significantly higher than those in stages I and II. The results of somatostatin immunoreactivity were consistent with those of in situhybridization.

CONCLUSION: The alteration of the expression of somatostatin mRNA was associated with the deve-lopment of gastric carcinoma and may play an important role in the process of tumor differentiation.

Relationship between HBV viremia level of pregnant women and intrauterine infection: neated PCR for detection of HBV DNA

AIM: To determine the incidence of hepatitis B virus (HBV) in trauterine infection and to explore the relationship between HBV viremia level of pregnant women and HBV intrauterine infection.

METHODS: Sixty-nine pregnant women were divided into three groups. Group A, 41 HBsAg positive patients, 14 of them were HBeAg positive (group A1), and 27 HBeAg negative (group A2); Group B, 12 HBsAg negative patients, but positive for anti-HBs and/or anti-HBe and/or anti-HBc; and Group C, 16 patients negative for all HBV markers. Blood samples of mothers were taken at delivery, samples of their infants were collected within 24 h after birth (before injection of HBIG and HBV vaccine). All the serum samples were stored at - 20 °C. HBV serum markers were tested by radioimmunoassay and HBV NDA were detected by nested polymerase chain reaction.

RESULTS: In group C, all of 16 newborns were negative for HBsAg and HBV DNA. In group A, 7 infants were HBsAg positive (17.1%), and 17 (41.5%) were HBV DNA positive (P < 0.05). The incidence of intrauterine HBV infection was much higher in group A1 than that in group A2 (HBsAg 42.9% vs 3.7%, HBV DNA 92.9% vs 14.8%, P < 0.05). The incidence of HBV intrauterine infection was significantly different between high and low HBV viremia of mothers (93.3% vs 42.9%, P < 0.05).

CONCLUSION: The incidence of HBV intrauterine infection is high when HBV DNA in newborns detected with nested PCR is used as a marker of HBV infection. It is related to HBV viremia level of mothers.

Effect of aging on cytoskeleton system of Kupffer cell and its phagocytic capacity

AIM: To investigate the age-related alterations of cytoskeleton system in liver Kupffer cell and their relation to the changed phagocytic function.

METHODS: The phagocytic function of Kupffer cells from rats of various ages (6 mo, 12 mo,18 mo and 24 mo) were quantitatively evaluated by phagocytosis of polystyrene beads. The actin distribution and measurement of Kupffer cell were determined by a phalloidin-TRITC method; and the myosin and vimentin distribution and measurement with indirect immunochemical staining.

RESULTS: Aging resulted in significant alterations of actin, myosin and vimentin distributions and reductions in Kupffer cell; the 3 cytoskeleton components of 24-mo-old Kupffer cell were significantly decreased to 68.0%, 84.9% and 75.5%, respectively of these of 6-mo-old Kupffer cell(P < 0.01,0.01 and 0.01). And these decreases had significant positive relations with the damaged phagocytosis of the aged Kupffer cell. γ values were 0.96(P < 0.05), 0.99(P < 0.01) and 0.95 (P < 0.05) respectively.

CONCLUSION: The cytoskeleton system of the aged Kupffer cell presents an evident state of senescence, which may be an important mechanism of decreased phagocytosis of the aged Kupffer cell.

Immunohistochemical detection of HCV infection in patients with hepatocellular carcinoma and other liver diseases

AIM: To detect HCV infection in patients with HCC and other liver diseases by the immunohistochemical method.

METHODS: The expression of HCV antigen was identified by means of LSAB (labelled streptavidin-biotin) method using anti-NS3 monoclonal antibody.

RESULTS: The positive rates of HCV antigen in the three groups of HCC, liver cirrhosis and hepatitis were 13.5% (7/52), 12.5% (2/16), and 10% (4/40) respectively, while in the samples from patients with constitutional jaundice and normal liver samples, no HCV antigen was found. HCV antigen could be seen in the nuclei and/or cytoplasms of carcinoma cells and/or pericancerous hepatocytes. In HCC, HCV antigen was more often seen in nuclei than in cytoplasms. The positive rate of HCV antigen in pericancerous tissues was higher than that in cancerous tissues.

CONCLUSION: HCV is associated with HCC, and HCV infection enhances the development of liver diseases. HCV affects the initiative period of HCC and induces the malignant phenotypic alteration of hepatocytes.

Establishment of a nonradioactive assay for2’-5’ oligoadenylate synthetase and its application in chronic hepatitis C patients receiving interferon-α

AIM: To establish a nonradioactive assay for 2’-5’ oligoadenylate synthetase (2-5 AS) and to measure the 2-5AS in peripheral blood mononuclear cell (PBMC) extracts of patients with chronic hepatitis C before IFN-α injection, 24 h and one month after the first injection.

METHODS: 2-5AS in cell extracts of PBMCs from 10 normal persons and 15 chronic hepatitis C patients were determined with PEI cellulose thin-layer chromatography.

RESULTS: The assay of 2-5AS in human PBMC was found to be rapid, sensitive, specific and reliable. The 2-5AS activity of PBMC in normal persons was in a quite low level (2.0%), and it was increased about ten-folds after stimulation of IFN (19.7%), (P < 0.01). In 15 chronic hepatitic C patients, the basal levels of 2-5AS before IFN treatment were higher than those of normal persons, being much higher in the group showing poor response to IFN treatment, but 24h after the first injection of IFN-α the 2-5AS level showed a more rapid and much greater rise in those patients with a good response.

CONCLUSION: 2-5AS may be a useful parameter of biological response during the IFN therapy.

Aflatoxin sufferer and p53 gene mutation in hepatocellular carcinoma

AIM: To study the p53 gene mutation and its relationship to aflatoxin B1 exposure in hepatocellular carcinoma (HCC).

METHODS: Restriction fragment length polymorphism analysis method was used in 62 HCC samples, and DNA direct sequencing in another 45 HCC samples.

RESULTS: In HCC and AFB1 high and low-risk areas, 36/52 (69%) and 2/10 (20%) cases were found losing the HaeIII allele respectively, suggesting one of the base G mutation at the p53 gene codon 249. Similar results appeared in DNA direct sequencing, 20/35 (57%) and 1/10 (10%) respectively mutated at the codon 249 third base G to C transversion.

CONCLUSION: In HCC after AFB1 exposure, mutation of p53 gene is fixed at codon 249 third base and take the form of G to T transversion. This is a definite marker of mutation which is induced by AFB1 mutagen. It is applicable for molecular epidemiologic survey of the sufferers of AFB1 among HCC cases and for discovering more unknown natural AFB1 contaminated areas.

A new rat model of portal hypertension induced by intraportal injection of microspheres

AIM: To produce a new rat model of portal hypertension by intraportal injection of microspheres. METHODS: Measured aliquots of single or different-sized microspheres (15, 40, 80μm) were injected into the portal vein to block intrahepatic portal radicals. The resultant changes in arterial,portal,hepatic venous and splenic pulp pressures were monitored. The liver and lungs were excised for histological examination.

RESULTS: Portal venous pressure was elevated from basal value of 0.89-1.02 kPa to a steady-state of 1.98-3.19 kPa following the sequential injections of single- or different-sized microspheres, with a markedly lowered mean arterial pressure. However, a small-dose injection of 80 μm microspheres (1.8 × 10⁵) produced a steady-state portal venous pressure of 2.53 × 0.17 kPa, and all rats showed normal arterial pressures. In addition, numerous microspheres were found in the lungs in all experimental groups.

CONCLUSION: Portal hypertension can be reproduced in rats by intraportal injection of microspheres at a small dose of 80 μm (1.8 × 10⁵). Intrahepatic portal-systemic shunts probably exist in the normal rat liver.

Relationship between tumor necrosis factor-α and liver fibrosis

INTRODUCTION: To interstate the relationship between tumor necrosis factor-α and liver fibrosis in patients with chronic liver disease.

METHODS: Radioimmunoassay was made in 20 patients with mild chronic hepatitis (CMH), 20 patients with severe chronic hepatitis (CSH), 51 patients with liver cirrhosis (LC) and 32-normal persons to determine the contents of tumor necrosis factor-α (TNF-α), laminin-(LN) and hyaluronate (HA) in serum. The changes in and relationship between TNF-α, LN and HA were analyzed. The TNF-α and collagen III were determined using mmunohistochemical studies in liver tissues from 32 persons including 7 normal persons, 3 patients with MCH, 5 patients with SCH and 17 with LC.

RESULTS: TNF-α, LN and HA levels in serum of CSH and LC patients were significantly higher than those in healthy controls (SCH: 1.11 ± 0.59, 130.7 ± 17.2, 219.1 ± 121.3; LC: 0.92 ± 0.66, 156.8 ± 31.7, 400.5 ± 183.7, P < 0.05-0.01), which increased gradually, and correlated positively with each other in all patients with liver diseases (n = 91, gamma= 0.3149, P < 0.01). TNF-α contents-showed a remarkably positive correlation with HA and LN levels in CMH and CSH (LN: n = 40, gamma = 0.3404, P < 0.05 HA: n = 40, gamma = 0.3847, P < 0.05). The total collagen content of MCH, SCH and LC increased gradually in liver biopsy specimens. The number of TNF-α positive cells increased significantly in liver tissues from patients with SCH and LC (62%; 45%; P < 0.01). TNF-α positive cells were mainly located in the periportal areas.

CONCLUSION: TNF-α may be related to liver fibrosis, and might promote liver fibrosis.

Arylsulfatase, β-galactosidase and lysozyme in gastric cancer cells and its relationship to invasion

AIM: To study the distribution of arylsulfatase, β-galactosidase and lysozyme in gastric cancer cells, and its relationship to differentiation and invasion of gastric cancer cells.

METHODS: Histochemical, immunohistochemical and ruthenium red (RR) electrocytochemical technique for three types of hydrolases and proteoglycans in pericancerous matrix in 33 cases of gastric cancer were observed under light and electron microscopy.

RESULTS: The expression intensities of arylsulfatase, β-glactosidase and lysozyme in mucinous cell carcinomas were more intensive than those in well-differentiated and poorly-differentiated adenocarcinomas ( P < 0.05-0.01). The fibrous tissues smooth muscle and proteoglycans close to the cancer cells were degraded. They were found in the region far from the cancer cells. Expression of three enzymes mentioned above was low in adenocarcinoma cells, and fibrous tissues and RR granules were present and intact near the well-differentiated and poorly-differentiated adenocarcinoma cells.

CONCLUSION: Mucinous cell carcinoma may release various hydrolases into extracellular matrix, inducing degradation of pericancerous matrix and facilitating cancer cell invasion and metastasis.

Pancreatic tumor: DSA diagnosis and treatment

AIM: To study the clinical significance of the diagnosis and catheterized interventional treatment of digital subtraction angiography (DSA) for pancreatic tumors.

METHODS: Ninety-two patients with pancreatic tumor, 69 males and 23 females, aged from 41 to 70 years (mean 57.1 years) were diagnosed with DSA. Sixty-one patients with pancreatic cancer were treated with transcatheter celiac and superior mesenteric arterial anticancer agents (MMC 20 mg, EADM 40 mg and 5-FU 2.0 g) infusion (TCSAI).

RESULTS: The DSA diagnoses were confirmed by operations and pathological examinations, with a coincidence 82.6% rate of, and a therapeutic effective rate of 42.6%.

CONCLUSION: DSA is of diagnostic value for pancreatic tumors, and helpful in understanding the course of the disease, judging the prognosis and selecting the therapeutic regimen, and could improve the chemotherapeutic effect as well.

Clinical and experimental study of therapeutic effect of Weixibaonizhuan pills on gastric precancerous lesions

AIM:To observe the therapeutic effect of Wei-xibaonizhuan pills on gastric precancerous lesions.METHODS: Thirty patients with gastric precancerous lesions were treated with Weixibaonizhuan pills for 3 months. Of the 36 cases, 13 (36.1%) were mild atrophic gastritis, 14 (38.9%) moderate atrophic gastritis and 9 (25.0%) severe atrophic gastritis; among them 22 (61.1%) and 27 cases (75.0%) were accompanied with intestinal metaplasia (IM) and dysplasia (DYS) respectively. Of the 36 patients, 20 were men and 16 women, aged from 30-60 years and those aged 30-59 years accounted for 61.1%. The course of disease ranged from 3 months to 21 years, and 20 (55.6%) of them had a course of 5-10 years. The clinical manifestations were fullness of the abdomen (31 cases),abdominalgia (27 cases), anorexia (30 cases), gas eructation (26 cases), acid regurgitation (6 cases) and loose stool (9 cases). When treatment ended, the improvement of patients' clinical symptoms, atrophy of gastric mucosa, IM and DYS were analysed.RESULTS: After 3 months' treatment with Wei-xibaonizhuan pills,7 cases recovered, 11 cases were much improved, 13 cases showed some improvement, and 5 cases were ineffective; the total rate of symptomatic improvement was 86.1%. Of the 13 cases with mild atrophic gastritis, 11 cases changed into superficial gastritis, and 2 cases had no changes. Of the 14 cases of moderate atrophic gastritis, 4 cases changed into superficial gastritis, 7 cases changed into mild atrophic gastritis, and 3 cases had no changes. Five of 9 cases of severe atrophic gastritis were reduced to moderate atrophic gastritis, and 4 cases had no changes. The total effective rate was 77.8% in chronic atrophic gastritis. Of the 9 cases with mild IM, IM disappeared in 6 cases and 3 showed no change. Of the 10 cases with moderate IM, it disappeared in 2 cases, 5 cases changed to ild IM, and 3 cases had no change. One of the 4 cases of severe IM changed to moderate IM and 3 had no change. The total effective rate was 63.6% in IM. Of the 16 cases of mild DYS, 11 cases showed disappearance of DYS and 5 had no change. In 9 cases of moderate DYS, 2 showed disappearance, 5 changed to mild DYS and 2 had no change. Two cases of severe DYS, both showed no change. The total effective rate was 66.7% in DYS. Before treatment, the I, II, III and IV degree positive expressions of CEA were present in 13, 12, 9 and 2 cases, respectively, whereas after treatment, the positive expressions were present in 25, 7, 3 and 1, respectively. Before treatment, the I, II, III and IV degree positive expressions of PCNA were present in 16, 11, 10 and 4 respectively, but after treatment, they were present in 21, 9, 5 and 1 respectively. In short, the positive expressions of CEA and PCNA of gastric mucosa were significantly decreased after treatment (P < 0.01).CONCLUSION: Weixibaonizhuan pill has a therapeutic effect in gastric precancerous lesions.

Relationship between different sources of drinking water, water quality improvement and gastric cancer mortality in Changle County-A retrospective-cohort study in high incidence area

AIM:To investigate the relationship between different sources of drinking water supply, water quality improvement and gastric cancer mortality rate in a high risk area.METHODS: A retrospective-cohort survey was carried out in all towns of this county to study the effect of different sources of drinking water supply and water quality improvement on gastric cancer mortality rate.RESULTS: The gastric cancer mortality rate among the population 124.05/10(5) drinking river water was obviously higher than that of drinking shallow well water (74.85/10(5)) (P < 0.01) according to the Zhanggang Town 16 years accumulated data. The same pattern was presented in 7 towns after balancing the confounders. The gastric cancer mortality rate of population drinking river water was 86.03/10(5), which was higher than those drinking shallow well water (62.03/10(5)) and tap water (29.78/10(5))(P < 0.01). When the drinking water switched from river and well water to tap water, the gastric cancer incidence decreased to 30.33/10(5) and 26.10/10(5), and the gastric cancer mortality decreased by 59% and 57% respectively.CONCLUSION: The quality of drinking water is one of the important factors of increased incidence of gastric cancer in Changle County, and water quality improvement has a beneficial effect, but the cause of high gastric cancer incidence may be multi-factorial in this area.

A study of the relationship between trace element Mo and gastric cancer

AIM:To study the relationship between trace element Mo and gastric cancer.MATERIALS AND METHODS: Soil samples were collected according to its type in different areas of Jiangxi Province; available molybdenum content in soil was measured by catalytic polarography and rank correlation method was used to analyse correlation between the mean of soil available molybdenum and mortality rate of gastric cancer in each county and city in Jiangxi Province. Gastric cancer cases were selected from the authors' hospital, occiput hair was collected to measure its molybdenum content with an atomic absorption spectrograph and controls were selected from the same hospital for comparison. Gastric cancer cases were selected from three hospitals at the same time, blood samples were taken on an empty stomach and serum molybdenum contents were measured with the atomic absorption spectrograph, and controls were selected from the same hospitals. Blind method was used in the whole course (chemical analysts did not know the source and nature of samples).RESULTS: A negative correlation existed between soil available molybdenum content and mortality rate of gastric cancer (r = -0.285, P < 0.05); hair molybdenum contents of gastric cancer cases were lower than those of healthy controls (0.308&mgr;g/g plus minus 0.673&mgr;g/g and 0.707&mgr;g/g plus minus 0.561&mgr;g/g respectively, P < 0.01); serum molybdenum contents of patients were also lower than those of healthy controls (21.84&mgr;g/L plus minus 7.49&mgr;g/L and 25.38&mgr;g/L plus minus 8.58&mgr;g/L respectively,P< 0.05).CONCLUSION: Deficiency of molybdenum may be one of the risk factors in gastric cancer.

Overexpression of P53 and its risk factors in esophageal cancer in urban areas of Xi'an

AIM:To investigate the risk factors of esophageal cancer (EC) in urban areas of Xi'an and to determine the association between overexpression of P53 and these risk factors.METHODS: All cases (89) and controls (97) were permanent residents in urban areas of Xi'an, all cases of primary EC had been histologically confirmed, controls were inpatients with non-cancer and nonsmoking-related disease. Cancer tissues and tissues adjacent to the cancer of 65 cases and 24 available normal esophageal tissues of controls were detected for P53 overexpression by the immunohistochemical method.RESULTS: The smoking and familial history of cancer were significantly associated with EC in Xi'an inhabitants. The laboratory assay indicated that P53 positive stain in EC was 50.0%(34/65)and 6.1%(4/65) in tissues adjacent to the cancer, but no positive stain was found in normal esophageal tissues of controls. The results showed that P53 overexpression in EC was closely related to smoking and cases with familial history of cancer.CONCLUSION: Smoking and familial cancer history were important risk factors for EC,and the alteration of P53 gene may be due to smoking and inheritance factors.

Effect of garlic and garlic-green tea mixture on serum lipids in MNNG-induced experimental gastric carcinoma and precancerous lesion

INTRODUCTION:To study effect of garlic and garlic-green tea mixture on serum contents of Tch,LDL and HDL in MNNG induced gastric carcinoma (GC) and precancerous lesion (PL) in Wistar rats.METHODS:Serum contents of Tch,LDL and HDL in normal control group (n=10,NG),MNNG group (n=30,MG),prevention group (n=30,PG),treatment group I (n=20,TG I) and treatment group II(n=20,TG II) were detected by PGE 6000/COD.RESULTS:Serum Tch and LDL of rats of MG (6.86±1.39 3.72±1.10) and its GC(6.95±1.37 3.77±1.08) and PL(6.42±1.04 3.56±0.74) were lower than that of NG (8.74±1.89 5.89±1.61) PG(7.73±3.18 4.96±2.89) and its GC(8.36±3.41 5.93±3.31) and PL(7.45±3.16 4.55±2.71),TGI(8.86±1.75 5.38±1.76) and its GC (9.10±2.27 5.55±2.51) and PL (8.61±1.17 5.22±0.55) and TG II (8.16±0.76 5.32±0.72) and its GC(8.52±0.67 5.96±0.48) and PL (8.02±0.79 5.09±0.65),respectively (P <0.01-0.05).Serum HDL of MG rats (2.76±0.48) and its GC(2.79±0.48) were remarkably higher than that of MG (2.20±0.85) and GC of PG (2.24±0.38) (P <0.05).CONCLUSION:Experimental gastric carcinoma and precancerous lesion were associated with hypocholesterolaemia,LDL and HDL.Garlic and garlic-green tea mixture can inhibit and reverse MNNG-induced gastric carcinoma and precancerous lesion in Wistar rats.

Expression of glutathione S-transferase placental mRNA in hepatic preneoplastic lesions in rats

AIM:To detect glutathione S-transferase placental (GST-P) mRNA expression in hepatic preneoplastic lesions in rats.METHODS: Using Solit-Farber model, the GST-P mRNA expression was observed in hepatic preneoplastic lesions induced by diethylnitrosamine (DEN) in rats and normal and regenerated hepatic tissues in the control group by in situ hybridization.RESULTS: GST-P mRNA was mainly expressed in altered hepatic foci (AHF) and some of the oval cells in hepatic preneoplastic lesions and the extent of its expression was different among various foci or/and positive cells in the same focus whereas no expression was observed in normal and regenerated hepatic tissues.CONCLUSION: Cells in AHF and oval cells may be the preneoplastic cells in the experimental hepatocellular carcinoma at the molecular level and heterogeneity exists in GST-P transcription levels.

Influence of diet intake on liver function test

AIM: To study whether dietary intake influences liver function test.

METHODS: Blood samples were obtained from patients liver diseases (n = 100) and controls (without liver diseases; n = 100) first at 07: 00 in the morning (fasting state) and then 2 h after a meal (fed state). The Hitachi-7150 automatic biochemistry analyzer was used to assess the following liver function indexes: Serum bilirubin, thymol turbidity test, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, gamma glutamyl transferase, SP, A and G. Statistical significance of differences between inter-group values was determined using SAS software.

RESULTS: None of the indexes showed statistically significant differences between the fasting state and the fed state (P = 0.476-0.978).

CONCLUSION: Liver function test can be performed after a meal.

Comparison of preoperative TN staging of gastric carcinoma by endoscopic ultrasonography with CT examination

AIM: To assess the accuracy and limitations of endoscopic ultrasonography (EUS) in the preoperative staging of gastric carcinoma in comparison with computed tomography (CT).

METHODS: According to the new (1987) TN staging, 62 patients with gastric carcinomas were examined preoperatively by EUS and the results compared with those of postoperative pathological TN staging. CT of abdomen was performed before surgery for 32 of the patients.

RESULTS: The overall accuracy of T staging was 83.9% for EUS and 28.1% for CT. For the detection of regional lymph node metastases, EUS accuracy was 79.0%, sensitivity 80.0% and specificity 87.5%, versus 50.0% accuracy for CT. The coincidence of perigastric infiltration was 90.0% for EUS and 41.2% for CT. The most frequent causes of misdiagnosis by EUS were microscopic tumor invasion and peritumorous inflammatory or fibrous changes.

CONCLUSION: EUS is a reliable method for the clinical evaluation of locoregional extension of gastric cancer and more accurate than CT in the preoperative staging of gastric carcinoma.

Treatment of cancerous ascites and radical gastrectomy with intraperitoneal hyperthermic double-distilled water and cis-diaminodichloro-platinum perfusion

AIM: To study the therapeutic effect of intraperitoneal hyperthermic double-distilled water and cis-diaminodichloro-platinum (DDP) perfusion for cancerous ascites and radical gastrectomy.

METHODS: LACA mice were injected peritoneally with H₂₂ cancer cells (2 × 10⁷ tumor cells). Five days later, the mice received treatments with either intraperitoneal perfusion of 37 °C isotonic fluid (group I), or 43 °C simple hyperthermic double-distilled water (group II), isotonic fluid (group III), DDP (group IV) or a combination of the hyperthermic double-distilled water with DDP (group V). A clinical experiment with intraperitoneal hyperthermic double-distilled water perfusion with DDP was carried out from September 1991 through September 1993 with 32 advanced gastric cancer patients who had undergone radical gastrectomy.

RESULTS: In comparison with the untreated control group of cancer cell-bearing LACA mice, the mice in all treatment groups showed near complete obliteration of cancer cells in the peritoneal cavity, markedly reduced ascites, prolonged survival times, and reduced growth of peritoneal cancerous nodes. In the clinical experiment, all 32 patients with advanced carcinoma had achieved satisfactory results at the 1-year follow-up, but had unsatisfactory results at the 2-year follow-up.

CONCLUSION: The intraperitoneal hyperthermic double-distilled water perfusion with DDP inhibited the occurrence of ascites in LACA mice bearing cancer cells, and prolonged the lifetime of patients with gastric cancer who had undergone radical gastrectomy.

Overproduction of nitric oxide inhibits vascular reactivity in portal hypertensive rats

AIM

To evaluate the relationship between nitric oxide (NO) and hyperdynamic circulatory status in portal hypertension.

METHODS

Twenty male Sprague Dawley rats (weighing 200 ± 20 g) were randomized into two groups: portal hypertension group (n = 12) and sham-operated control group (n = 8). The portal hypertensive model was established by means of graded constriction of the portal vein. The concentrations of nitrite (NO2 (-)) in the portal vein and peripheral blood were measured by fluorometric assay to reflect NO levels. The reactivity of isolated abdominal aortic rings from rats with partial portal vein constriction and controls was determined by assessing response to administration of potassium chloride (KCl) (10-80 mmol/L) and phenylephrine (10(-9)-10(-4) mol/L) with or without preincubation with NO synthase inhibitor Nω-nitro-L-arginine (L-NNA).

RESULTS

Serum concentrations of NO2 (-) in the portal vein blood (0.766 ± 0.097 μmol/L) and peripheral blood (0.687 ± 0.092 μmol/L) were elevated in portal hypertensive rats, as compared with the concentrations in controls (0.613 ± 0.084 μmol/L and 0.591 ± 0.045 μmol/L respectively, both P < 0.01). In addition, the rates of NO2 (-) in portal vein blood were markedly higher than those in peripheral blood (P < 0.05) in the portal hypertensive rats. Abdominal aortic rings from rats with portal vein constriction exhibited significantly impaired contractility to phenylephrine and KCl, as compared with the control rats. The EC50 values of KCl were markedly higher in the portal hypertensive rings (26.5 ± 0.9 mmol/L) than in the control rings (22.3 ± 1.7 mmol/L, P < 0.01), as were the EC50 values of phenylephrine (37.2 ± 0.4 nmol/L vs control rings: 28.1 ± 0.2 nmol/L, P < 0.01). After preincubation of rings with L-NNA, the difference in EC50 values between portal hypertensive and control rings was no longer statistically significant for either KCl (20.18 ± 0.8 mmol/L vs 19.4 ± 1.2 mmol/L, P > 0.05) or phenylephrine (22.4 ± 1.8 nmol/L vs 21.8 ± 1.4 nmol/L, P > 0.05). However, the maximal concentrations of KCl and phenylephrine for inducing contractions were still significantly lower in the portal hypertensive rings (1.08 ± 0.1 g and 1.43 ± 0.14 g) than in the control rings (1.21 ± 0.11 g and 1.72 ± 0.11 g respectively, both P < 0.05). Thus, addition of the NO synthase inhibitor L-NNA could partially restore contractile responses to KCl and phenylephrine in portal hypertensive rings.

CONCLUSION

NO overproduction inhibits the vascular reactivity to vasoconstrictors, and it might be one of the main causes of vasodilatation and hyperdynamic circulatory status in portal hypertension.

Determination of β-glucuronidase in human colorectal carcinoma cell lines

AIM: To study the relationship between β-glucuronidase and the invasiveness of human colorectal carcinoma cell lines.

METHODS: Six colorectal carcinoma cell lines, including three well-differentiated (CX1, CCL187, and CCL229) and three poorly differentiated ones (CCL227, CCL228, and Clone A), were analyzed by Fischman’s method to determine the concentration of β-glucuronidase in the medium.

RESULTS: Low levels of β-glucuronidase (activity range: 1.29 to 1.96 μg/106 cells·h) were associated with poor invasiveness. This finding was in contrast to the elevated levels of the enzyme (2.46-3.37 μg/106·h) detected in the medium derived from the more aggressively invasive cells (CCL 227, CCL 228, Clone A, and CCL 229).

CONCLUSION: Highly invasive colorectal carcinoma cells secreted higher levels of β-glucuronidase than the poorly invasive cells. Determination of secreted β-glucuronidase might represent a useful in vitro measurement tool to assess the invasiveness of colorectal carcinoma.

Influence of fever on biliary elements of guinea pigs

AIM: To study the influence of fever on biliary elements and gallstone formation in guinea pigs.

METHODS: Sixty guinea pigs were randomly divided and fed either a lithogenic diet (to induce gallstone formation) or a normal diet (for use as the non-gallstone controls), and each group was then subdivided into fever or non-fever subgroups. The fever condition was induced by subcutaneous injection of boiled non-fat milk (1 mL/kg, once a week for 4 wk). After 45 d, all the animals were euthanized for analysis; however, 36 h prior to euthanasia, the guinea pigs in the fever subgroups were injected subcutaneously with turpentine (1 mL/kg) to maintain the fever condition. Gallbladder lumens were examined and bile samples were analyzed.

RESULTS: Gallstone incidence was highest (40%, 6/15) in the group of animals that were fed the lithogenic diet and had fever. Compared to the non-fever subgroups, the fever subgroups had significantly higher total bile protein and bilirubin.

CONCLUSION: Fever influences biliary elements and may contribute to gallstone formation in guinea pigs.

Establishment and application of an experimental model of human fetal hepatocytes for investigation of the protective effects of silybin and polyporus umbellalus polysaccharides

AIM: To establish a new experimental model system of human fetal hepatocytes to study the mechanisms underlying the protective effect of silybin and polyporus umbellalus polysaccharides (PSP) on the cellular ultrastructure.

METHODS: Human fetal hepatocytes were obtained from the liver of a human fetus that resulted from a medically necessary induced labor; the mother provided informed consent for sampling, experimental use and publication of findings. The hepatocytes were cultured and then pretreated with silybin or PSP or without either (control), after which the treated cells were exposed to CCl₄ for 4 h. Changes in cellular ultrastructure were observed by scanning electron microscopy and transmission electron microscopy, and changes in alanine aminotransferase (ALT), aspartate aminotransferase (AST) and superoxide dismutase (SOD) were assayed.

RESULTS: Levels of ALT and AST were significantly decreased, and level of SOD was elevated in the two pretreatment groups following CCl₄ exposure, as compared to the control group. The cellular integrity and ultrastructure were well preserved in the two pretreatment groups but were seriously damaged in the control group.

CONCLUSION: The CCl₄-induced hepatotoxic cell model system of human fetal hepatocytes is an effective tool for studying the hepatoprotective effect of drugs and may be applicable for studies to screen medicines for treatment of hepatitis.

Seropharmalogical effects of Fuzheng Huayu decoction on rat Ito cell morphology and function in culture

AIM: To investigate the mechanisms of anti-liver fibrosis actions of Fuzheng Huayu (FZHY) decoction, which acts to strengthen the body’s resistance and promote blood circulation.

METHODS: Ito cells were isolated from rats and cultured. Serum samples were collected from healthy (normal) rats after administration of FZHY decoction and added to the subcultured cells. The effects of FZHY decoction on the Ito cells were investigated by contrast microscopy (to observe cell morphology), [³H]Pro incorporation assay (cell viability), [³H]TdR incorporation and MTT colorimetric assay (cell proliferation), and [³H]Pro incorporation and collagenase digestion (collagen synthesis rate).

RESULTS: The rat sera samples from rats treated with FZHY decoction had no influence on Ito cell morphology, but improved cell viability and markedly inhibited cell proliferation and collagen synthesis. The magnitude of these effects showed dependence on treatment dosage and drug concentration in serum.

CONCLUSION: The seropharmalogical method can be efficiently used to investigate the pharmacological mechanism of anti-fibrotic traditional Chinese herbs and formulae. Inhibition of Ito cell proliferation and collagen synthesis may be two of the major mechanisms underlying the anti-fibrosis actions of the FZHY decoction.

Anti-human AFP variant monoclonal antibody in radioimmunodetection of primary hepatocellular carcinoma

AIM: To investigate the affinity of AFP-R-LCA monoclonal antibody (AFP-R-LCA McAb) for AFP-positive primary hepatocellular carcinoma (HCC) cells.

METHODS: AFP-R-LCA McAb was labeled by ¹³¹I. Eleven cases of HCC with AFP positivity, 6 with AFP negativity, and 4 with hepatitis B-related cirrhosis were investigated by radioimmunodetection.

RESULTS: The ¹³¹I-AFP-R-LCA McAb immunoreacted with 9 of the HCC AFP-positive cases (9/11), but with none of the 6 AFP negative HCC cases or of the 4 cirrhosis patients. ¹³¹I-AFP-R-LCA McAb at a small dose (7.4 × 10⁷ Bq/300 μg) was associated with no side effects as determined by the liver function test, prothrombin time (Pt) test and thyroid gland function test (P > 0.05). Two cases of AFP-positive HCC were not imaged because of large tumor size (diameter > 10 cm) and higher AFP concentration in serum (20000 μg/L).

CONCLUSION: AFP-R-LCA McAb has a strong and special affinity to AFP-positive HCC cells and may be useful as a carrier for radioimmunodetection and radioimmunotherapy.

Effects of endotoxin on expression of ras, p53 and bcl-2 oncoprotein in hepatocarcinogenesis induced by thioacetamide in rats

AIM

To evaluate the relationship between expression of ras, p53 and bcl-2 gene products and hepatocarcinogenesis since the endotoxemia produced from lipopolysaccharide administration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide.

METHODS

The hepatocarcinoma model was induced by 6-mo oral intake of 0.03% thioacetamide. During the hepatocarcinoma modeling process, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied for quantitative analysis of the expression of oncogene proteins.

RESULTS

In this model system, overexpression of ras p21 protein mainly occurred in the precancerous cell population or in cells in the early stage of hepatocyte transformation. The levels of ras p21 declined when nuclear DNA aneuploidy increased. Expression of bcl-2 protein slowly and steadily rose, with more hepatocytes staying in S + G2M phases, as the hepatocarcinoma became more malignant. p53 was moderately expressed during hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes in levels of ras, p53 and bcl-2 gene products.

CONCLUSION

Overexpression of oncogene ras p21 was considered likely to be a precursor of premalignant hepatocytes and possibly as responsible for the initiation of hepatocarcinogenesis. Bcl-2 protein expression is proportional to the severity of malignancy in hepatocarcinogenesis. p53 may be involved in a key pathway underlying the transformation and development processes of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expression of oncogene proteins reflects the properties of the premalignant and malignant cells, but is not directly related to endotoxemia statistically.

Analysis of amino acid constituents of gallstones

AIM: To seek drugs that will efficaciously dissolve bilirubin, glycoprotein and black stones and that will represent improved lithotriptic agents to resolve cholesterol stones, and to study the amino acid constituents of gallstones.

METHODS: According to characteristics determined by infrared spectroscopy and to the contents of bilirubin determined by semi-quantitative chemical analysis, 30 of 148 cases of gallstones were selected and divided into 5 groups. Amino acids of the 30 cases were detected by high-speed chromatography.

RESULTS: The quantity of amino acids was highest in black stones (226.9 mg/g) and lowest in pure cholesterol stones (1.4 mg/g). In the 5 groups of gallstones, the quantity of amino acids followed the hierarchy of black stone > mixed bilirubin stone and glucoprotein stone > mixed cholesterol stone > pure cholesterol stone. The proportions were: 95.95:29.02 and 28.05:5.78:1. Aliphatic amino acids accounted for approximately 50% of the total amino acids in the gallstones, with glycine accounting for 15.3% of the total amount of the 17 kinds of amino acids.

CONCLUSION: For mixed stones, the higher level of bilirubin, the higher content of amino acids. Acidic amino acids were relatively higher in bilirubin stones than in cholesterol stones.

Plasma D (-)-lactate as a new marker for diagnosis of acute intestinal injury following ischemia-reperfusion

AIM: To observe the kinetics of D (-)-lactate alteration in both portal and systemic circulation systems, and its relationship with intestinal injury in rats subjected to acute intestinal ischemia-reperfusion.

METHODS: Anesthetized rats underwent a 75-min superior mesenteric artery occlusion followed by a 6-h reperfusion. Plasma D (-)-lactate levels were measured by an enzymatic spectrophotometric assay.

RESULTS: Intestinal ischemia for 75 min resulted in a significant elevation of D (-)-lactate levels in the portal vein, as compared with the baseline values (P < 0.05). Plasma D (-)-lactate levels had a tendency to further increase after reperfusion, up to 6 h. Similar alterations in D (-)-lactate were also found in systemic circulation, and there were no significant differences between the portal and systemic circulations at any time point. Moreover, the macropathological evaluation scores were significantly correlated to the portal D (-)-lactate levels in animals at various time points (r = 0.415, P < 0.01). In addition, there was a remarkable rise of endotoxin concentration within the portal vein at the end of the 75-min ischemic period (P < 0.05), reaching a peak at 2 h post-reperfusion.

CONCLUSION: Acute intestinal ischemia is associated with failure of the mucosal barrier resulting in increased plasma D (-)-lactate levels in both portal and systemic blood. The subsequent reperfusion might further increase D (-)-lactate levels, which are correlated to the macropathological alterations. Plasma D (-)-lactate may be a useful marker of intestinal injury following both ischemia and reperfusion insults.