作者： 刊期： 2009年第07期
作者： 刊期： 2009年第07期
作者： 刊期： 2009年第07期
INTRODUCTIONGastrin is a trophic gastrointestinal hormone which is secreted by G cell. Gastrin has long been considered a growth stimulatory hormone for mucosa of the gastrointestinal tract[1]. The growth responses of certain colorectal cancer cells, and xenografts, can be stimulated by endogenous gastrin[2]. Protein kinase C (PKC) is a family of isozymes that plays a crucial role in transducing signals of many hormones, growth peptides,neurotransmitters, and its activation is crucial in tumor promotion[3]. PKC is also involved in regulating cellular proliferation[4].
作者： 刊期： 2000年第02期
INTRODUCTIONIn order to study the therapeutic mechanisms of emodin, an extract of Rhubarb (Rhizoma et Radix Rhei, a traditional Chinese herbal medicine), and sandostatin in the treatment of acute necrotizing pancreatitis (ANP), we used the two drugs in rat models of the disease and observed the changes of plasma thromboxane-2 (TXB2),6-ketoprostaglandin F1α (6-keto-PGF1α) and prostaglandin E2 (PEG2).
作者： 刊期： 2000年第02期
INTRODUCTIONEndothelins (ETs) has a potent and sustained vasoconstrictive effect on a variety of blood vessels.The vascular smooth muscle cell (VSMC) is the target for ETs. VSMC of the whole body contains endothelin receptor (ETR)[1]. A great number of experiments have shown that three distinct complementary DNAs of ETR have been identified i. e., endothelin A receptor (ETA receptor),endothelin B receptor ( ETB receptor ) and endothelin C receptor (ETc receptor). ETA receptor was expressed in VSMC responsible for the contraction[2]. The aim of this study is to confirm the effects of endotoxin on the activity of ETR, and the transcription and expression of ETA receptor mRNA in hepatic and intestinal tissues.
作者： 刊期： 2000年第02期
INTRODUCTIONVascular endothelial growth factor (VEGF) which is also known as vascular permeability factor (VPF) is a heparin-binding, dimeric polypeptide growth factor and a potent mitogen for endothelial cells.VEGF can stimulate the endothelial cell growth and enhance the motility through its two known receptors flt-1 and KDR[1]. Acting through these receptors, VEGF may stimulate angiogenesis and promote tumor progression. VEGF12l, as one of the four VEGF protein isoforms containing the least number of amino acids, has all the biological function of VEGF and is the ideal isoforms for further studying VEGF at molecular levels[2]. In this study, we cloned
作者： 刊期： 2000年第02期
INTRODUCTION The esophageal carcinoma is a common malignant tumor in Linzhou City (Linxian) of Henan Province in northern China. Although the etiology and natural history of esophageal carcinoma are not clear, a substantial amount of evidence has been provided to suggest that the development of human esophageal squamous cell carcinomas (SCC) is a multistage progressive process[1-4] An early indicator of abnormality in persons predisposed to esophageal SCC is an increased proliferation of esophageal epithelial cells,morphologically manifested as basal cell hyperplasia (BCH), and dysplasia (DYS), and carcinoma in situ, which could be considered precancerous lesions of esophageal SCC[1-4].
作者： 刊期： 2000年第02期
INTRODUCTIONThe treatment of human epithelial malignancies is limited by drug resistance and toxic and side effects,which results in the failure in the treatment of majority of advanced cancer victims. To seek for a new, and specific antineoplastic therapy will provide hope for tumor treatment. Although disordered intermediary metabolism in cancer cells has been known for many years, much of the work focused on abnormal glucose catabolism. At the same time, little attention has been paid to fatty acid synthasis in tumor tissues, dispite of the significance of fatty acid synthase (FAS) in some clinical human ovarian[1], breast[2], colorectal[3],and prostatic cancers[4,5]. Tumor cells which express high levels of fatty acid synthesizing enzymes use endogeneously synthesized fatty acids for membrance biosynthesis and appear to export large amounts of lipid. In contrast, normal cells preferentially utilize diary lipid.
作者： 刊期： 2000年第02期
INTRODUCTION According to the therapeutic effect and strategy of antisense RNA for hepatocellular carcinoma (HCC), we have specifically synthesized partial cDNA of human insulin-like growth factor Ⅱ (IGFⅡ ) and constructed IGF-Ⅱ cDNA antisense eukaryotic expression vector. The constructed vector was introduced into hepatoma cell line SMMC-7721 to block the intrinsic IGF- Ⅱexpression. The biological behavior changes of hepatoma cells were observed. All these would provide scientific basis for IGF- Ⅱ antisense RNA in the treatment of HCC.
作者： 刊期： 2000年第02期
INTRODUCTIONThe liver is one of the organs, which have potential regenerative capability in mammalian animal[1].The study of the canine model indicated that the liver could regenerate to original size after 70% hepatectomy in only two weeks[2]. So it is a hot research topic for the cellular and molecular mechanism of liver regeneration. Accumulated results demonstrated that the hepatocyte growth factor (HGF)[3], insulin-like growth factor Ⅰ and Ⅱ (IGF-Ⅰ, Ⅱ )[4], epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha)[5] and insulin[6] are among the most important growth factors for liver regenerative regulation. In recent years, a heat-stable protein in the serum of the patients with various liver diseases has been noted for its potential stimulation effects on the liver regeneration, and this growth factor is called hepatocyte-stimulatory substance (HSS).
作者： 刊期： 2000年第02期
INTRODUCTIONA newly discovered DNA virus,transfusion transmitted virus (TTV), was reported as a cause of post-transfusion hepatitis of unknown etiology in Japan[1]. In order to investigate TTV prevalence in southern China, a study was carried out among blood donors, patients with liver diseases and hemodialysis to determine the epidemiological charateristics.
作者： 刊期： 2000年第02期
INTRODUCTIONThe recent studies have shown that rhubarb has not only the effect of removing stasis by purgation, but also intestinal barrier effects[1,2]. In order to further clarify the intestinal barrier mechanism of rhubarb, we studied the effects of rhubarb decoction and the active ingredients of rhubarb on the cytoplasmic free calcium in isolated intestinal mononuclear cells (INT-MNC)
作者： 刊期： 2000年第02期
INTRODUCTIONMacrophages play an important role in tumor lysis and growth inhibition. They can be activated to a tumoricidal state by a variety of agents such as IFNr, TNFa or IL2. The killing machanisms of activated macrophages have been extensively investigated[1,2]. Recently, it has been proved that antibody dependent cellular cytotoxicity (ADCC) is one of the potent arms to lyse tumor cells resistant to cytotoxic macrophages,and that the antitumorous effect of a macrophage activator is significantly augmented by the combined use of mAbs capable of inducing ADCC to tumor cells[3].
作者： 刊期： 2000年第02期
INTRODUCTION Although liver transplantation for irreversible liver diseases is increasingly prevalent worldwide, patient die while waiting for donors because of organ shortages. One important problem commonly encountered is that fatty livers often affect the outcome of liver transplantation. It is reported that the incidence of abnormal fatty livers in autopsies after accidental death ranged from 15% to 24%.Since fatty livers may result in a primary nonfunction (PNF) liver graft, which contributes to an increased risk of mortality[1], they are usually out of consideration in liver transplantation.However, some fatty livers can be successfully transplanted. Therefore, how to choose fatty livers as donor organs correctly is the crux of success in liver transplantation.
作者： 刊期： 2000年第02期
INTRODUCTIONAlthough the long-term postoperative survival rate of gastric cancer (GC) patients has been improved significantly since the local dissection of lymph node was widely used in China, yet the low curative resection rate and the high recurrence rate from peritoneal and hepatic metastases hinder it from further improvement. To alter the current unsatisfactory status of GC treatment, a sequential triple therapeutic scheme (STTS), consisting of preoperative regional intra-arterial chemotherapy,curative resection of GC, and intra-operative or early postoperative intraperitoneal chemotherapy, was designed and adopted in this department since 1989. The follow-up data demonstrated that the therapeutic response of STTS is rather satisfactory.The results are reported as follows.
作者： 刊期： 2000年第02期
INTRODUCTION The antitumor activity of norcantharidin (NCTD),the demethylated analogue of cantharidin, was studied in the early 1980s in China. NCTD has no side effects on urinary organs which cantharidin has shown and is easier to synthesize, and it can inhibit the proliferation of several tumor cell lines as well as transplanted tumors. Clinical trials with NCTD as a monotherapeutic agent indicated that NCTD had beneficial effects in patients with different kinds of digestive tract cancers, such as primary hepatoma,carcinomas of esophagus and gastric cancer, but no depressive effect on bone marrow cells. NCTD can increase the white blood cell count by stimulating the bone marrow and has some antagonistic effect against leukopenia caused by other agents. The exact cellular and molecular mechanisms of NCTD on tumor cells have not yet been elucidated to date[1-3].
作者： 刊期： 2000年第02期
INTRODUCTIONAmino acid consumption test (AACT) has a high sensitivity and specificity in evaluating exocrine pancreatic insufficiency[1,2], but its diagnostic value to exocrine pancreatic insufficiency in Chinese has not been well understood. In this study, the oral reagent stimulating pancreatic secretion (O-AACT) was used instead of cerulein (I-AACT) for amido acid consumption test and the dignostic efficiency of O-AACT was evaluated and compared with I-AACT on the exocrine pancreatic insufficiency in Chinese.
作者： 刊期： 2000年第02期
AIM To investigate the effects of taxol on SMMC-7721 human hepatoma and its mechanisms. MLETHODS In vitro cell growth was assessed by trypan blue exclusion method. Experimental hepatoma model was established by seeding SMMC-7721 cells subcutaneously into Balb/c (nu/nu) nude mice. In vivo tumor growth was determined by measurement of tumor diameter with Vernier calipers. The syntheses of DNA,RNA and protein were analyzed by incorporation of 3H-thymidine, 3H-uridine and 3H-leucine respectively. Using light and electron microscopes to observe the morphological changes of cells including mitosis and apoptosis.RESULTS Taxol was effective against SMMC 7721 human hepetoma cell growth in the ranges of 2.5 nmol/L - 10 nmol/L with mitotic arrest and apoptosis in vitro. DNA, RNA and protein syntheses in cells were also obviously suppressed by in vitro treatment of taxol for 72 h. Taxol at 2.5 nmol/L reduced 3H-thymidine uptake to about 34% of the control value (P＜0.05). Increasing the dose of taxol to 20 nmol/L resulted in a greater decrease in 3Hthymidine incorporation to 60% of the control value (P＜0.01). At a concentration of 20 nmol/L, the 3H-uridine and 3H-leucine uptakes were reduced to 52% (P＜0.05) and 63%(P＜0.01), respectively. In vivo, taxol significantly inhibited SMMC-7721 tumor growth at 10 mg/kg, i.p., once daily for 10 d. A more than 90% decrease in tumor volume was observed by day 11 (P＜0.01) similarly with mitotic arrest and cell apoptosis.CONCLUSION Taxol has a marked anticancer activity in SMMC-7721 human hepatoma both in vitro and in nude mice. Its mechanisms might be associated with mitotic arrest, subsequently,apoptosis of the hepatoma cells. No obvious toxicity was observed with in vivo administration of taxol.
作者： 刊期： 2000年第02期
AIM To investigate the expression of integrins in rats liver during 3 '-Me-DAB induced hepatocarcinogenesis and to find out the relationship between integrins and liver cancer metastasis.METHODS The expressions of integrins α1, α2,α3 and α5 and epidermal keratin (EK) were observed by immunohistochemical PAP method.RESULTS In the normal liver tissues,hepatocytes express integrins α1 and α5 and in the bile duct epithlium, EK. In liver cirrhosis,hepatocytes highly express integrins α1, α2, α3 and α5 and in hyperplsstic bile duct epithelium,integrins α1, α5 and EK. Expression of integrins α1, α2, α3 and α5 were obviously decreased in the preneoplsstic nodules and primary carcinoma but expressions of integrins α1 and α5 in metastasis in the lung and diaphragme were higher than those in primary carcinoma.CONCLUSION Integrins α1 and α5 may play a major role in chemically induced hepatocarcinogenssis and metastasis in rats.
作者： 刊期： 2000年第02期
AIM To evaluate the possibility of using cultured human hepatocytes as a bridge between bioartificial liver and liver transplantation.METHODS In this experiment, the efficacy of extracorporeal bioartificial liver support system (EBLSS) consisting of spheriodal human liver cells and cultured hepatocytes supernatant was assessed in vivo using galactosamine induced rabbit model of fulminant hepatic failure.RiESULTS There was no difference of survival between the two groups of rabbits, but in the supported rabbits serum alanine aminotransferase, total bilirubin and creatinine were significantly lower and hepatocyte necrosis was markedly milder than those in control animals. In addition, a good viability of human liver cells was noted after the experiment.CONCLUSION EBLSS plays a biologic role in maintaining and compensating the function of the liver.
作者： 刊期： 2000年第02期
AIM To study the agglutination pattern of Helicobacter pylori coccoid and spiral forms.METHODS Assays of agglutination and agglutination inhibition were applied using fifteen commercial lectins. RESULTS Strong agglutination was observed with mannose-specific Concanavalin A (Con A ),fucose-specific Tetragonolobus purpureas ( Lotus A ) and N-acetyl glucosamine-specific Triticum vulgaris (WGA) lectins. Mannose and fucose specific lectins were reactive with all strains of H. pylori coccoids as compared to the spirals. Specific carbohydrates, glycoproteins and mucin were shown to inhibit H. pylori lectin-agglutination reactions. Pre-treatment of the bacterial cells with formalin and sulphuric acid did not alter the agglutination patterns with lectins. However, sodium periodate treatment of bacterial cells were shown to inhibit agglutination reaction with Con A, Lotus A and WGA lectins. On the contrary, enzymatic treatment of coccoids and spirals did not show marked inhibition of H. pylori-lectin agglutination. Interestingly, heating of H.pylori cells at 60℃ for 1 hour was shown to augment the agglutination with all of the lectins tested. CONCLUSION The considerable differences in lectin agglutination patterns seen among the two differentiated forms of H. pylori might be attributable to the structural changes during theevents of morphological transformation,resulting in exposing or masking some of the sugar residues on the cell surface. Possibility of various sugar residues on the cell wall of the coccoids may allow them to bind to different carbohydrate receptors on gastric mucus and epithelial cells. The coccoids with adherence characteristics like the spirals could aid in the pathogenic process of Helicobacter infection.This may probably lead to different clinical outcome of H. pylori associated gastroduodenal disease.
作者： 刊期： 2000年第02期
