Non-steroidal anti-inflammatory drug-induced small intestinal damage is Toll-like receptor 4 dependent

BACKGROUND

Enterobacteria and cytokines both play roles in the pathophysiology of NSAID-induced enteropathy. Toll-like receptor (TLR) 4 recognises lipopolysaccharide (LPS), resulting in activation of an inflammatory cascade via the accessory protein MyD88.

AIMS

To investigate role of TLR4 in inflammatory responses in indomethacin-induced enteropathy.

METHODS

Indomethacin was administered p.o. to non-fasting rats and mice to induce small intestinal damage. The extent of such damage was evaluated by measuring the injured area stained dark blue with Evans blue. Rats were given antibiotics (ampicillin, aztreonam or vancomycin) p.o., or intraperitoneal LPS (a TLR4 ligand) or neutralising antibodies against neutrophils, tumour necrosis factor (TNF)-alpha, or monocyte chemotactic protein (MCP)-1. Furthermore, the intestinal ulcerogenicity of indomethacin was examined in TLR4-mutant, TLR4(-/-), and MyD88(-/-) mice.

RESULTS

Indomethacin induced small intestinal damage with an increase in expression of TNF-alpha and MCP-1 in both rats and mice. Antibodies against neutrophils, TNF-alpha and MCP-1 inhibited the damage by 83%, 67% and 63%, respectively, in rats. Ampicillin and aztreonam also inhibited this damage, and decreased the number of Gram-negative bacteria in the small intestinal contents of the rat. However, vancomycin, which exhibited no activity against Gram-negative bacteria, had no preventive effect against this damage. Administration of LPS 1 h after indomethacin aggravated the damage, whereas LPS pretreatment inhibited it with reduction of expression of TLR4 and cytokines. In TLR4-mutant mice, the damage and cytokine expression were markedly inhibited. TLR4(-/-) and MyD88(-/-) mice were also resistant to the damage.

CONCLUSIONS

Indomethacin may injure the small intestine through a TLR4/MyD88-dependent pathway.

Intraoperative surgical clearance confirmation of tongue carcinomas using ultrasound

OBJECTIVES

The existence of tumour cells on the surgical margin can be shown in frozen sections. However, there has been no method to obtain information about surgical clearance intraoperatively. We propose a simple method to confirm the surgical clearance of tongue carcinomas during surgery.

METHODS

Just after the resection of a tumour in a conventional manner, the resected fresh specimen was immersed in a gelatine solution, maintaining its original shape and orientation, and refrigerated for solidification of the gelatine. Then ultrasound observation of the gelatine-embedded specimen was performed from the surface of the gelatine.

RESULTS

Very fine images could be obtained easily and without any specialist skills.

CONCLUSIONS

With this method, the operator can easily obtain information about surgical clearance during the operation.

Interleukin-10 gene transfer to peritoneal mesothelial cells suppresses peritoneal dissemination of gastric cancer cells due to a persistently high concentration in the peritoneal cavity

Interleukin (IL)-10 has potent biological properties including an inhibitory action on the proliferation and metastasis of various cancer cells. However, it is difficult to maintain a high concentration of this cytokine as it has a short half life. In this study, we evaluated whether peritoneal mesothelial cells (PMCs) could be suitable for maintaining a high concentration of IL-10 using adenoviral gene transfer. We also evaluated the therapeutic effects of an intraperitoneal injection with adenoviral vector containing mouse IL-10 gene (Ad-mIL-10) using a mouse peritoneal dissemination model of MKN45 gastric cancer cells. We demonstrated that in vitro transfection efficiency of a recombinant adenovirus containing the bacterial beta-galactosidase gene (Ad-LacZ) was approximately 10-fold higher for primarily isolated PMCs than MKN45. The entire peritoneum was transfected until 3 weeks after an intraperitoneal Ad-LacZ injection. Ad-mIL-10 treatment increased intraperitoneal IL-10 levels until 3 weeks after treatment, and then significantly inhibited peritoneal cancer growth by inhibiting angiogenesis. This treatment also improved cachexia and prolonged mice survival. We thus concluded that IL-10 gene transfer in PMCs could be a new strategy for the prevention of peritoneal dissemination of gastric cancer due to the resulting persistently high IL-10 concentration in the peritoneal cavity.

Changes in temporomandibular disc position during growth in young Japanese

PURPOSE

To detect the initial changes in temporomandibular disc position during growth with MRI examination in a prospective longitudinal study of a young Japanese population.

METHODS

Forty-four temporomandibular joints in 22 healthy asymptomatic volunteers, mean age 11.8 years, age range 9-16 years, were examined by MRI. They were re-examined 2-3 years later. The mean age and age range at the second examination were 14.5 years and 12-19 years, respectively. The discs were assessed at three different locations by oblique sagittal planes at the lateral, central and medial parts, and the displacement was evaluated as a partial anterior or total anterior position.

RESULTS

Six joints already had a partial anterior position of the disc at the initial examination and no developmental change in disc position was observed during the examination period. Nine joints developed partial disc displacement during the examination period. Every partial displacement was observed at the lateral part of the disc. One joint developed a total anterior position from the lateral to the medial images.

CONCLUSIONS

Initial changes in the disc position are likely to start from the lateral part of the joint in the early teenage years and are often asymptomatic.

Comparison of gastrointestinal symptoms and psychological factors of functional dyspepsia to peptic ulcer or panic disorder patients

Symptoms of functional dyspepsia (FD) may look like those of peptic ulcers or panic disorders. But, there is no comparative data between the symptoms of peptic ulcers or panic disorders.

METHODS

To evaluate general symptoms, we used the previously validated questionnaires: 1. the Gastrointestinal Symptom Rating Scale (GSRS), 2. the Self-Rating Depression Scale (SDS), 3. the State-Trait Anxiety Inventory (STAI), and 4. the Coping Inventory for Stressful Situations (CISS). Ninety-six patients with FD (ulcer-like, dysmotility-like, and nonspecific: 28.1 %, 41.7 %, and 30.2 %) diagnosed according to the Rome II criteria, 24 peptic ulcer patients, 21 panic disorders, and 50 healthy controls were enrolled in this study.

RESULTS

Total GSRS score of FD was higher than controls (12.8 +/- 1.2 vs. 5.9 +/- 0.7), and similar to peptic ulcers. Ratio over than a cut-off SDS score of FD was higher than controls (28 % vs. 11 %), although it was lower than panic disorders (65 %). Ratios over than cut-off scores of state- and trait-anxiety of FD were higher than controls (74 % and 62 % vs. 50 % and 36 %) and tended to be higher than peptic ulcers. Positive ratio of state-anxiety scores of FD was similar to panic disorders. As these scores increased, morbidity rate of FD (FD/FD+control) increased (P for trend <0.01). Among CISS scores, task-oriented coping scores of FD tended to be low compared to controls, but emotion-oriented coping scores of FD and controls were significantly lower than panic disorders.

CONCLUSION

Severity of gastrointestinal symptoms but not anxiety of FD was similar to peptic ulcers. Psychological scales of FD were also similar to panic disorders except for the emotion-oriented coping. These findings suggested that the complicated pathogenesis of FD was similar to but not completely consistent with peptic ulcers or panic disorders.

Functional evaluations of the parotid and submandibular glands using dynamic magnetic resonance sialography

PURPOSE

To evaluate the functional differences between the parotid and submandibular glands using dynamic MR sialography.

METHODS

In 30 volunteers, the time-dependent changes (dynamic changes) in the maximum area of the detectable parotid and submandibular gland ducts on dynamic MR sialographic images were analysed.

RESULTS

Dynamic changes in the parotid gland ducts were detectable on MR sialographic images in all volunteers, but images of the submandibular gland ducts were detectable in only 23 volunteers. In addition, the dynamic changes in the submandibular gland ducts in these 23 subjects were less than those seen in the parotid gland ducts. A relationship was found between the changing ratio of parotid (Pearson r=0.448, P=0.013) or submandibular gland ducts (Pearson r=0.418, P=0.047) and the salivary flow rate during the stimulation period.

CONCLUSIONS

Dynamic MR sialography allows evaluation of rest and stimulated functioning and morphological evaluation of the parotid and submandibular glands. This technique appears to have many possible applications in the dental, medical and biological fields.

Morphological features of cartilage observed during mandibular distraction in rabbits

Ossification during distraction osteogenesis can be classified as intramembranous or endochondral. It is not known whether cartilage in the distraction gap is transformed into new bone. The aim of this study was to investigate the morphological features of ossification in the transition of cartilage to bone during mandibular distraction osteogenesis in a rabbit model. A cortical osteotomy was performed and custom-made devices were applied. Immediately after surgery, the devices were lengthened by 0.25 mm every 12h for up 10 days, during which time four rabbits were killed at 0, 5 and 10 days and examined using histological staining and immunohistochemical methods. Apoptotic cells were identified by an in-situ detection assay for nuclear DNA fragmentation using a modified TUNEL procedure, with several sections analyzed using software for histomorphometric analysis. The results showed that the amount of cartilage in the distraction gap was significantly decreased. The cartilage had ossified in two ways, termed endochondral ossification and transchondroid bone formation.

Are gastroprotective drugs useful for gastric ulcer healing: re-evaluation using current ICH E9 guidelines

Most of the gastroprotective drugs which had been marketed in Japan were considered to have insufficient rationale for use as ulcer treatments. Such drugs may have a crucial role in maintaining mucosal integrity by the mechanisms other than inhibition of acid secretion. We re-evaluated the effect of gastroprotective drugs on gastric ulcer healing using current ICH E9 guidelines. We collected reports of pivotal trials on healing rate of gastric ulcer with 9 kinds of gastroprotective drugs submitted in New Drug Applications. In the comparative trial of cetraxate vs. placebo, the healing rate of gastric ulcer at 8-week endoscopy in the cetraxate was significantly higher than that in the placebo groups (88.6% and 62.2%, p = 0.0062). Non-inferiority to cetraxate was confirmed for 8 kinds of gastroprotective drugs. In conclusion, the superiority of cetraxate over placebo and non-inferiority to cetraxate for 7 drugs was established in the respect of effect on ulcer healing.

Lafutidine can improve the quality of gastric ulcer healing in humans: a randomized, controlled, multicenter trial

Improving the quality of ulcer healing (QOUH) is one of the valid methods of prevention of relapse of gastric ulcers. We investigated the effect of lafutidine on the QOUH of gastric ulcer compared with famotidine in a randomized, multi-centre controlled trial. Consecutive 80 patients with a gastric ulcer were randomly assigned to receive twice daily either lafutidine (10 mg) or famotidine (20 mg) for 12 weeks. Esophagogastroduodenoscopy was performed to examine the ulcer healing rate and rate of flat type ulcer scars using dye-contrast. The gastric ulcer healing rate was 92.1% in the lafutidine group (35/38) and 94.7% in the famotidine group (36/38). The rate of flat-type ulcer scars was significantly higher in the lafutidine group (68.4%, 26/38) than in the famotidine group (42.1%, 16/38) (P = 0.021). In conclusion, the present study demonstrated that lafutidine, as compared to famotidine, yields a significantly superior QOUH in patients with gastric ulcers in the clinical setting.

Local delivery system of cytotoxic agents to tumors by focused sonoporation

Recently, ultrasound-targeting microbubble destruction has been employed in molecular gene therapy, and a new potent nonviral gene transfer method known as 'sonoporation' has been developed. We investigated the efficiency of sonoporation toward growth inhibition of human gingival squamous carcinoma cell line, Ca9-22, in vitro and in vivo. The cytotoxicity of bleomycin (BLM) was investigated using flow-cytometric analysis and Hoechst's staining in vitro assay systems. We found that the delivery of BLM by sonoporation induced cytotoxic effect toward Ca9-22 cells in vitro. Our in vivo results showed that tumors nearly disappeared in Ca9-22 cell-implanted nude KSN/slc mice treated with a low dose of BLM followed by sonoporation during the 4-week experimental period. Histological analysis revealed that the cytotoxic effect was mainly apoptosis. We previously reported that the cytolethal distending toxin B (cdtB) from Actinobacillus actinomycetemcomitans, a periodontopathic bacterium, is responsible for cell cycle arrest and apoptosis in vitro. Thus, we used sonoporation to transfect a cdtB-expressing plasmid into Ca9-22 cells and examined cell viability in vitro and in vivo. We found that an administration of cdtB-expressing plasmid followed by sonoporation-induced marked growth inhibition of Ca9-22 cells and apoptotic cells were also observed in vitro and in vivo. These findings suggest that local administration of cytotoxic agents with sonoporation is a useful method for molecular cancer therapy.

136 CLOSED SYSTEM OF GEL-LOADING-TIP VITRIFICATION FOR IN VITRO-PRODUCED BOVINE BLASTOCYSTS BEFORE AND AFTER BIOPSY

Ultra-rapid cooling by direct plunging of gel-loading-tip (GL-tip) into liquid nitrogen (LN2) contributed to the high post-warm survival rates of in-vitro-produced (IVP) bovine embryos (Tominaga and Hamada 2001 J. Reprod. Dev. 47, 267–273). Since GL-tip vitrification and other ultra-rapid vitrification methods have potential risk of microbiological contamination in the LN2, the current study was undertaken to develop a closed system of GL-tip vitrification for IVP bovine blastocysts before and after biopsy. Day 7 blastocysts were produced in vitro (Tominaga et al. 2000 Theriogenology 53, 1669–1680), and biopsied for sex determination (Tominaga and Hamada 2004 Theriogenology 61, 1181–1191). The blastocysts were exposed first to 10% ethylene glycol (EG) +10% DMSO in TCM-199/20% FCS for 2 min at 37°C, and then placed in vitrification medium with 20% EG + 20% DMSO + 0.6 M sucrose in TCM 199/20% FCS for 30 s at 37°C. Three to 4 blastocysts in 0.6 µL of the vitrification medium were aspirated into a GL-tip (NK-tip; Nippon Medical &amp; Chemical Instruments Co., Ltd., Osaka, Japan). Immediately before being plunged into LN2, the tip of the GL-tip was sealed by dipping into 100% glycerol at 4°C, and the opposite open end of the GL-tip was sealed by inserting a holding stick under LN2 vapor. After warming in 0.25 M sucrose solution at 37°C, the glycerol-seal was removed from the tip by gentle shaking. The blastocysts diluted in a two-step manner were cultured up to 72 h for survival assay. Within the 72 h of culture, intact embryos that initiated hatching and biopsied embryos that re-expanded were considered as surviving. Two more biopsied blastocysts derived from ovum pickup, IVF, and IVC were vitrified–warmed in the closed system, and then transferred to 2 recipients. The results indicate no significant difference in the post-thaw survival rates of either intact or biopsied blastocysts in both closed and open systems (Table 1). One recipient became pregnant and delivered a female calf. Gestation period (287 days) and birth weight (22 kg) were within the normal range of the Tajima strain of Japanese Black cattle. We reached the conclusion that the closed system of GL-tip vitrification was simple and highly effective for IVP bovine blastocysts before and after biopsy. Table 1. In vitro survival of intact and biopsied bovine blastocysts after GL-tip vitrification in closed and open systems

Dynamic magnetic resonance sialography as a new diagnostic technique for patients with Sjogren's syndrome

OBJECTIVE

To evaluate the clinical utility of dynamic magnetic resonance (MR) sialographic images as a diagnostic tool for patients with Sjögren's syndrome.

METHODS

The morphological findings and various kinds of functional parameters in volunteers on dynamic MR sialographic images were compared with those in five patients with definite Sjögren's syndrome.

RESULTS

On the MR sialographs of all five patients with Sjögren's syndrome, the so-called 'apple-tree appearance' was seen. The difference in two functional parameters using the dynamic MR sialographic data was elucidated between the two groups. The maximum area of the detectable ducts in the group of patients was significantly smaller (P < 0.001) than that in the group of volunteers. The ratio of change in the detectable ducts in the group of patients was significantly lower (P = 0.011) than that in the group of volunteers.

CONCLUSIONS

Our study suggests that dynamic MR sialographic data in addition to MR sialographic images might be useful for the diagnosis of Sjögren's syndrome.

Complete regression of low-grade mucosa-associated lymphoid tissue (MALT) lymphoma in the gastric stump after eradication of Helicobacter pylori

Recent studies have suggested that Helicobacter pylori (H. pylori)-associated gastritis may play an important role in the pathogenesis of primary gastric lymphoma. Recently, triple therapy using proton pump inhibitor, amoxicillin, and clarithromycin, has been established for the eradication therapy of H. pylori infection, and is also recommended for the treatment of the superficial type of low-grade gastric MALT (mucosa-associated lymphoid tissue ) lymphoma. MALT lymphoma of the gastric stump is rare, and total resection or chemotherapy for MALT lymphoma of the gastric stump has been previously reported. Therefore, there is no evidence that eradication therapy is effective for low-grade MALT lymphoma of the gastric stump. Our case illustrates the remarkable efficacy of eradication of H. pylori for low-grade MALT lymphoma of the gastric stump without other modalities such as surgery and systemic chemotherapy.

A simple method for bone positioning of mandibular segments

A simple bone-positioning technique is reported, using a combination of bone plates and a flexible tube filled with acrylic polymer. The flexible tube is solidified by injection of acrylic monomer. This technique is applicable for bone positioning after mandibular resection as well as positioning of the proximal segment after sagittal split ramus osteotomy. This technique has the advantages of greater simplicity and flexibility compared to previously reported methods of bone positioning.

Roles of cyclooxygenase 2 and microsomal prostaglandin E synthase 1 in rat acid reflux oesophagitis

BACKGROUND

Although prostaglandin E2 (PGE2), cyclooxygenase 2 (COX-2), and microsomal prostaglandin E synthase 1 (mPGES-1) are known to play a role in various inflammatory events, their roles in the pathogenesis of gastro-oesophageal reflux disease are not known.

AIMS

We examined the dynamics of COX-1, COX-2, mPGES-1, mPGES-2, cytosolic PGES (cPGES), and PGE2 synthetic activity in rat acid reflux oesophagitis and the effects of COX-2 inhibitors on the severity of oesophagitis.

METHODS

Acid reflux oesophagitis was induced by ligating the transitional region between the forestomach and the glandular portion and wrapping the duodenum near the pylorus. Rats were killed on day 3 (acute phase) or day 21 (chronic phase) after induction of oesophagitis.

RESULTS

Expression of COX-2 and mPGES-1 was markedly increased in oesophagitis while modest changes in COX-1, cPGES, and mPGES-2 expression were observed. COX-2 and mPGES-1 were colocalised in epithelial cells of the basal layer, as well as inflammatory and mesenchymal cells in the lamina propria and submucosa. COX-2 inhibitors significantly reduced the severity of chronic oesophagitis but did not affect acute oesophageal lesions. COX-2 inhibitors significantly inhibited the increase in PGE2 synthesis in oesophageal lesions on both days 3 and 21. Epithelial proliferation was significantly increased in the basal layer on day 21. Inflammatory cells and epithelial cells of the basal layer exhibited reactions for EP4 in oesophagitis.

CONCLUSION

PGE2 derived from COX-2 and mPGES-1 plays a significant role in the pathogenesis of chronic acid reflux oesophagitis, and possibly in basal hyperplasia and persistent inflammatory cell infiltration.

Methylation of the oestrogen receptor gene in non-neoplastic epithelium as a marker of colorectal neoplasia risk in longstanding and extensive ulcerative colitis

BACKGROUND

Surveillance colonoscopy is widely recommended in patients with longstanding and extensive ulcerative colitis (UC) in order to detect colorectal neoplasia at an early stage. However, it still remains questionable whether surveillance colonoscopy effectively enables early detection of UC associated neoplasia. There is a great need for sensitive markers to identify individuals at increased risk of neoplasia. The oestrogen receptor (OR) gene shows age related methylation in the colorectal epithelium and is methylated frequently in sporadic colorectal neoplasia, suggesting that OR methylation may predispose to colorectal neoplasia.

AIM

To clarify whether analysis of methylation of the OR gene in non-neoplastic epithelium can contribute to prediction of increased neoplasia risk in UC patients.

MATERIALS AND METHODS

A total of 165 non-neoplastic colorectal epithelia from 30 patients with longstanding and extensive UC, including 13 UC patients with neoplasia and 17 patients without, were evaluated. Methylation specific polymerase chain reaction was performed to determine the methylation status of the OR gene.

RESULTS

Methylation of the OR gene was detected in 54 of 70 (77.1%) non-neoplastic colorectal epithelia in UC with neoplasia but in only 23 of 95 (24.2%) without neoplasia. Methylation of the OR gene was significantly more frequent in non-neoplastic epithelium from UC with neoplasia than in chronic colitic epithelium from UC without neoplasia. Furthermore, in UC with neoplasia, the OR gene was extensively methylated in non-neoplastic epithelia throughout the colorectum compared with those in UC without neoplasia.

CONCLUSION

These results suggest that analysis of OR gene methylation may have potential as a useful marker for identifying individuals at increased risk of neoplasia among those with longstanding and extensive UC.

Famotidine vs. omeprazole: a prospective randomized multicentre trial to determine efficacy in non-erosive gastro-oesophageal reflux disease

BACKGROUND

Several studies in Western countries showed that proton-pump inhibitors are superior to histamine2-receptor antagonists or placebo in the treatment of non-erosive gastro-oesophageal reflux disease. The efficacy of acid-suppressive drugs for non-erosive gastro-oesophageal reflux disease in Japan, in which the prevalence of Helicobacter pylori infection is higher compared with Western countries, is unknown.

AIM

To compare the efficacy of famotidine and omeprazole in Japanese patients with non-erosive gastro-oesophageal reflux disease by a prospective randomized multicentre trial.

METHODS

A total of 98 patients received either famotidine 20 mg b.d. (n = 48) or omeprazole once daily (n = 50). Frequency of gastro-oesophageal reflux disease symptoms and health-related quality of life were evaluated at baseline and after 4 weeks of treatment. Complete relief was defined as no gastro-oesophageal reflux disease symptoms during the 7-day interval in week 4.

RESULTS

Complete relief was achieved in 23 (48%) of patients receiving famotidine and 28 (56%) of patients treated with omeprazole. In the famotidine group, complete relief rate in H. pylori-negative patients was significantly lower than H. pylori-positive patients (35% vs. 64%). Both famotidine and omeprazole improved most scales of health-related quality of life. Omeprazole significantly improved reflux score irrespective of H. pylori infection while famotidine significantly improved reflux score in H. pylori-positive patients but not in H. pylori-negative patients.

CONCLUSIONS

Omeprazole is more effective than famotidine for the control of gastro-oesophageal reflux disease symptoms in H. pylori-negative patients, while similar efficacy is observed in H. pylori-positive patients with non-erosive gastro-oesophageal reflux disease.

Utility of three dimension fast asymmetric spin-echo (3D-FASE) sequences in MR sialographic sequences: model and volunteer studies

OBJECTIVES

To evaluate the utility of 3D-FASE for the visualization of salivary gland ducts for use in MR sialographic sequences.

METHODS

We compared MR sialographic images and virtual endoscopic views from 3D-FASE with those from three kinds of sequences described by previous reports in a 3D parotid gland duct model and volunteer. The four sequences were two-dimension fast spin-echo (2D-FSE), three-dimension fast spin-echo (3D-FSE), two-dimension fast asymmetric spin-echo (2D-FASE), and three-dimension fast asymmetric spin-echo (3D-FASE).

RESULTS

In the 3D parotid gland duct model, image visibility on visual score was clearest with 3D-FSE, followed by 3D-FASE (P = 0.028). In the volunteers, the visualization of images improved in the following order: 3D-FASE > 3D-FSE > 2D-FSE > 2D-FASE.

CONCLUSIONS

The technique of 3D-FASE sequencing is more suitable and useful for MR sialography with an appropriate acquisition time.

Effects of ranitidine on quality of gastric ulcer healing compared with famotidine: a randomized, controlled, multicenter trial

Ranitidine has been found to have anti-inflammatory action as well as antisecretory action in experimental models. However, there are no reports in human gastric ulcer. The aim of this study was to investigate the effects of ranitidine compared with those of famotidine on the quality of gastric ulcer healing. We randomly assigned 69 consecutive patients with gastric ulcers to ranitidine (n = 34) or famotidine (n = 35) for 12 weeks, with endoscopic assessment of the quality of gastric ulcer healing and histological assessment of gastric mucosa 12 weeks after treatment started. Ulcer healing rates of over 95% were very similar in the two groups. The rates of ulcer scars with a flat pattern (good-quality healing) were significantly higher in the ranitidine group than in the famotidine group (per protocol, 63.0% and 34.5%, p = 0.033). The neutrophil infiltration score in the body mucosa treated with famotidine, but not ranitidine, significantly increased after treatment. In contrast, the mononuclear cell infiltration score in the antral mucosa treated with ranitidine, but not in that treated with famotidine, had significantly decreased. In conclusion, initial therapy with ranitidine significantly improved the quality of gastric ulcer healing and the histological scores of gastric mucosa compared with famotidine.

Repeated adenoviral administration into the biliary tract can induce repeated expression of the original gene construct in rat livers without immunosuppressive strategies

BACKGROUND

Systemic adenoviral readministration appears to be limited by immunogenicity.

AIMS

We examined the feasibility of repeated adenovirus mediated gene transfer into the liver via the biliary tract.

METHODS

Recombinant adenoviruses carrying a reporter lacZ gene were infused retrogradely into the common bile duct of rats. Transduction efficiency of the lacZ gene was estimated histochemically and quantitatively.

RESULTS

Retrograde administration of recombinant adenoviruses into the common bile duct of rats resulted in efficient transgene expression in the liver, specifically in hepatocytes, but not in biliary epithelia. Transduction efficiency induced by intrabiliary adenoviral administration was not substantially different from that induced by intraportal adenoviral infusion. Transgene expression in the liver was however transient, and development of neutralising antibodies against adenovirus was observed in serum but not in bile. When adenoviruses were readministered into the common bile duct, successful re-expression of the transgene in the liver was achieved despite the existence of neutralising antibodies in serum. Interestingly, although proliferation of adenovirus specific T cells in response to adenoviral readministration was suppressed significantly by immunosuppressive FK506 treatment, levels of transgene expression in the liver achieved by intrabiliary adenoviral readministration were not significantly different between animals treated with and without FK506. Furthermore, third adenoviral administration into the common bile duct also induced successful transgene expression in the liver.

CONCLUSIONS

These results suggest that adenovirus mediated gene transfer into the liver may be repeatable without immunosuppressive strategies in clinical settings by means of endoscopic retrograde cholangiography.

Correlation of MAP kinases with COX-2 induction differs between MKN45 and HT29 cells

BACKGROUND

Mitogen-activated protein (MAP) kinases, including extracellular signal-regulated kinases (ERK),c-Jun NH2-terminal kinases (JNK) and p38 MAP kinase (p38 MAPK) are important intermediates of the signal-transduction pathway from the cell surface to the nucleus. Expression of cyclooxygenase (COX)-2, associated with proliferation, apoptosis or both of gastrointestinal cancer cells, is mediated through MAP kinase families. However, the correlation between respective MAP kinase signals and COX-2 in the proliferation of gastric and colon cancer cells has not been well elucidated.

AIM

We examined the effect of selective inhibitors of MAP kinases and COX-2 on serum-induced proliferation of gastric (MKN45) and colon (HT29) cancer cells.

METHODS

After 24-h serum starvation, cancer cells were stimulated with 2% serum and COX-2 inhibitors (NS398 10 micromol/L, or etodolac 100 micromol/L) or 1 h after preincubation with inhibitors for ERK (PD98059 20 micromol/L) or p38 MAPK (SB203580 10 micromol/L). Phosphorylated MAP kinases and COX-2 protein were evaluated by Western blotting, and the proliferation of cancer cells was estimated by 3H-thymidine incorporation. Transcription factors nuclear factor-kappaB and CREB were assayed by an electorophoretic mobility shift assay.

RESULTS

Serum increased the proliferation of MKN45 and HT29 cells by 280% and 200%, respectively, compared with the control levels (100%). In both cancer cells, phosphorylated MAP kinases were increased within 30 min after stimulation. PD98059 and SB203580 inhibited the serum-induced proliferation of MKN45 by 21% and 51% and of HT29 by 81% and 69%, respectively. NS398 and etodolac inhibited the proliferation of HT29 by 21% and 41%, respectively, but not that of MKN45. PD98059 and SB203580 also suppressed serum-induced expression of COX-2 protein in HT29 cells. In addition to the activation of MAP kinases and COX-2, activities of nuclear factor-kappaB and CREB were also increased during HT29 cell proliferation.

CONCLUSIONS

These results suggest that the correlation of MAP kinases with COX-2 induction for cell proliferation differs between MKN45 and HT29 cells.