Safety and efficacy of granulocyte and monocyte adsorption apheresis in patients with active ulcerative colitis: a multicenter study

Active ulcerative colitis (UC) is characterized by activation and infiltration of granulocytes and monocytes/macrophages into the colonic mucosa. The infiltrated leukocytes can cause mucosal damage by releasing degradative proteases, reactive oxygen derivatives, and proinflammatory cytokines. The aim of this trial (conducted in 14 specialist centers) was to assess safety and efficacy of granulocyte and monocyte adsorption apheresis in patients with active UC most of whom were refractory to conventional drug therapy. We used a new adsorptive type extracorporeal column (G-1 Adacolumn) filled with cellulose acetate beads (carriers) of 2 mm in diameter, which selectively adsorb granulocytes and monocytes/macrophages. Patients (n = 53) received five apheresis sessions, each of 60 minutes duration, flow rate 30 ml per minute for 5 consecutive weeks in combination with 24.4 +/- 3.60 mg prednisolone (mean +/- SE per patient per day, baseline dose). During 60 minutes apheresis, 26% of granulocytes, 19.5% of monocytes and 2% of lymphocytes adsorbed to the carriers. At week 7, 58.5% of patients had remission or improved, the dose of prednisolone was reduced to 14.2 +/- 2.25 mg (n = 37). The apheresis treatment was fairly safe, only eight non-severe side effects (in 5 patients) were reported. Based on our results, we believe that in patients with active severe UC, patients who are refractory to conventional drugs, granulocyte and monocyte adsorption apheresis is a useful adjunct to conventional therapy. This procedure should have the potential to allow tapering the dose of corticosteroids, shorten the time to remission and delay relapse.

Atrophic gastric changes in both Helicobacter felis and Helicobacter pylori infected mice are host dependent and separate from antral gastritis

BACKGROUND/AIMS

The role of host factors has been neglected in studies of the pathogenesis of Helicobacter associated disease. The aim of this study was to assess the response of different mouse strains to infection with a single strain of Helicobacter felis.

METHOD

Six strains of inbred mice were infected with the identical H felis culture and were killed at one month, two months, and six months after infection to assess histopathological changes. In addition, two strains of mice were infected with a mouse adapted strain of H pylori and examined at six months after infection.

RESULTS

In SJL, C3H/He, DBA/2, and C57BL/6 infected mice, severe to moderate chronic active gastritis was observed only in the body of the stomach, which increased in severity over time with specialised cells in the body glands being replaced. As the severity of this damage in the body increased and atrophic changes were seen, the level of bacterial colonisation of the antrum decreased. In contrast, in BALB/c and CBA mice, there was only mild gastritis in the antrum, no remarkable changes were detected in their body mucosa, and no atrophy was seen over time. In both these strains of mice, heavy bacterial colonisation was seen, which tended to increase over the period of the experiment. Of particular importance in this experiment was that bacterial colonisation was mainly restricted to the antrum yet the atrophy, when present, was only observed in the body of the stomach. H pylori infected C3H/He mice showed moderate colonisation of the antrum, which persisted up to six months with little development of atrophy. In contrast, H pylori in C57BL/6 mice showed excellent colonisation of the antrum at two months but six months after infection there was moderate to severe body atrophy, which was associated with a loss of bacteria from the antrum.

CONCLUSIONS

These findings challenge current concepts of the development of Helicobacter induced atrophy in that active chronic gastritis of antrum or the body mucosa, or both, is not a prerequisite. They also suggest an autoimmune basis for the pathology although no autoantibody or antibody to the H+/K+ ATPase was detected. Loss of infecting helicobacters from the stomach together with development of an atrophic gastritis in the body of the stomach is similar to the pattern found in certain H pylori infected human subjects.

Potent inhibitory action of the gastric proton pump inhibitor lansoprazole against urease activity of Helicobacter pylori: unique action selective for H. pylori cells

The gastric proton pump inhibitor lansoprazole, its active analog AG-2000, and omeprazole dose dependently inhibited urease activity extracted with distilled water from Helicobacter pylori cells; the 50% inhibitory concentrations were between 3.6 and 9.5 microM, which were more potent than those of urease inhibitors, such as acetohydroxamic acid, hydroxyurea, and thiourea. These compounds also inhibited urease activity in intact cells of H. pylori and Helicobacter mustelae but did not inhibit ureases from other bacteria, such as Proteus vulgaris, Proteus mirabilis, and Providencia rettgeri. The mechanism of urease inhibition was considered to be blockage of the SH groups of H. pylori urease, since SH residues in the enzyme decreased after preincubation with lansoprazole and glutathione or dithiothreitol completely abolished the inhibitory action. The SH-blocking reagents N-ethylmaleimide and idoacetamide were also examined for their inhibition of the urease activity; their 50% inhibitory concentrations were 100- to 1,000-fold higher than those of lansoprazole. These results suggest that lansoprazole and omeprazole can potently and selectively inhibit H. pylori urease and that inhibition may be related to earlier findings indicating that these compounds have selective activity against HP growth.

Chemokine mRNA expression in gastric mucosa is associated with Helicobacter pylori cagA positivity and severity of gastritis

AIM

To investigate the association between the quantity of gastric chemokine mRNA expression, severity of gastritis, and cagA positivity in Helicobacter pylori associated gastritis.

METHODS

In 83 dyspeptic patients, antral and corpus biopsies were taken for semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and histological grading of gastritis. Gastritis was evaluated by visual analogue scales. Quantities of chemokine (IL-8, GRO alpha, ENA-78, RANTES, MCP-1) RT-PCR products were compared with G3PDH products. Each sample was also evaluated for the presence of cagA and ureA mRNA by RT-PCR.

RESULTS

mRNA expression of all five chemokines was significantly greater in H pylori positive than in H pylori negative mucosa. In H pylori positive patients, in the antrum C-X-C chemokine mRNA expression was significantly greater in cagA positive patients than in cagA negative patients, but there were no significant differences in C-C chemokine mRNA expression. In H pylori positive patients, chemokine mRNA expression in the corpus was less than in the antrum. In contrast to the antrum, only GRO alpha mRNA expression was significantly greater in cagA positive infection. Polymorphonuclear cell infiltration was correlated with C-X-C chemokine mRNA expression. Significant correlations were also found between bacterial density and C-X-C chemokine mRNA expression.

CONCLUSIONS

In H pylori infection, C-X-C chemokines may play a primary role in active gastritis. Infection with cagA positive H pylori induces greater gastric chemokine mRNA expression in the antral mucosa, which may be relevant to the increased mucosal damage associated with cagA positive H pylori infection.

A multicenter, double-blind study on triple therapy with lansoprazole, amoxicillin and clarithromycin for eradication of Helicobacter pylori in Japanese peptic ulcer patients

BACKGROUND

Two triple therapies with lansoprazole (LPZ)/amoxicillin (AMPC)/clarithromycin (CAM) for eradication of Helicobacter pylori were studied in multicenter, double-blind fashion to evaluate the eradication rate of H. pylori and safety of eradiation treatment in Japanese patients with H. pylori-positive active gastric ulcers or duodenal ulcers.

METHODS

Patients were randomly chosen for the control treatment of LPZ 30 mg twice a day (b.i.d.; Group A-LPZ-only) or the test treatments of LPZ 30 mg plus AMPC 750 mg and CAM 200 mg b.i.d. (Group B-LAC200) and LPZ 30 mg, AMPC 750 mg and CAM 400 mg b.i.d. (Group C-LAC400). All eradication treatments lasted for a period of 7 days. Successful eradication was assessed by culture and gastric histology 1 month after completion of the ulcer treatment.

RESULTS

The eradication rates of H. pylori in the full analysis set were 0% in Group A-LPZ-only, 87.5% in Group B-LAC200 and 89.2% in Group C-LAC400 for gastric ulcer and, 4.4% in Group A-LPZ-only, 91.1% in Group B-LAC200 and 83.7% in Group C-LAC400 for duodenal ulcer. The eradication rates of Group B-LAC200 and Group C-LAC400 were 89.2% (95% CI: 84.8-93.7%) and 86.4% (95%CI: 81.5-91.3%) in total in the full analysis set, 89% (95% CI: 84.3-93.7%) and 85.3% (95%CI: 80.1-90.5%) in the per protocol set. The eradication rates in Groups B-LAC200 and group C-LAC400 were statistically significantly higher than the rate in Group A-LPZ-only for both gastric ulcer and duodenal ulcer patients (p <.0001 for both).

CONCLUSION

A satisfactorily high H. pylori eradication rate was obtained in Japanese ulcer patients with the triple therapy regimen consisting of LPZ 30 mg, AMPC 750 mg, and CAM 200 mg b.i.d.

Akt-dependent nuclear localization of Y-box-binding protein 1 in acquisition of malignant characteristics by human ovarian cancer cells

Y-box-binding protein 1 (YB-1), which is a member of the DNA-binding protein family containing a cold-shock domain, has pleiotropic functions in response to various environmental stimuli. As we previously showed that YB-1 is a global marker of multidrug resistance in ovarian cancer and other tumor types. To identify YB-1-regulated genes in ovarian cancers, we investigated the expression profile of YB-1 small-interfering RNA (siRNA)-transfected ovarian cancer cells using a high-density oligonucleotide array. YB-1 knockdown by siRNA upregulated 344 genes, including MDR1, thymidylate synthetase, S100 calcium binding protein and cyclin B, and downregulated 534 genes, including CXCR4, N-myc downstream regulated gene 1, E-cadherin and phospholipase C. Exogenous serum addition stimulated YB-1 translocation from the cytoplasm to the nucleus, and treatment with Akt inhibitors as well as Akt siRNA and integrin-linked kinase (ILK) siRNA specifically blocked YB-1 nuclear localization. Inhibition of Akt activation downregulated CXCR4 and upregulated MDR1 (ABCB1) gene expression. Administration of Akt inhibitor resulted in decrease in nuclear YB-1-positive cancer cells in a xenograft animal model. Akt activation thus regulates the nuclear translocation of YB-1, affecting the expression of drug-resistance genes and other genes associated with the malignant characteristics in ovarian cancer cells. Therefore, the Akt pathway could be a novel target of disrupting the nuclear translocation of YB-1 that has important implications for further development of therapeutic strategy against ovarian cancers.

High prevalence of the CagA-positive Helicobacter pylori strains in Japanese asymptomatic patients and gastric cancer patients

BACKGROUND

Several studies have shown that infection of Helicobacter pylori strains possessing cagA is associated with atrophic gastritis and gastric cancers.

METHOD

In 58 pairs of early gastric cancer patients and sex- and age-matched controls, isolated H. pylori strains were tested for possession of cagA. The presence of atrophic gastritis was also examined.

RESULTS

Proportions of cagA-positive strains were 100% in cancer patients and 92.3% in controls. Atrophic gastritis was seen in 96.7% and 95.8% of cancer and control patients in whom cagA-positive strains (NS) were detected. However, it was seen in only 20% of H. pylori-negative control patients (P < 0.01).

CONCLUSIONS

The present results do not suggest any specific association between cagA-positive strains and gastric cancer. However, frequent prevalence of cagA-positive strains might be associated with the high incidence of atrophic gastritis in Japanese populations.

IL-18 and IL-12 induce intestinal inflammation and fatty liver in mice in an IFN-gamma dependent manner

BACKGROUND

In murine models of inflammatory bowel disease, colonic inflammation is considered to be caused by an aberrant Th1-type immune response.

AIM

To investigate if systemic administration of interleukin (IL)-12 and IL-18 to wild-type BALB/c mice induces liver injury and intestinal inflammation, and if pathological changes are observed, what cytokines are involved.

METHODS

Mice (BALB/c-wild-type (wt), MRL-lpr/lpr, BALB/c-interferon gamma knock out (IFN-gamma KO), C57BL/6-inducible nitric oxide synthase (iNOS) KO, and BALB/c tumour necrosis factor alpha (TNF-alpha) KO) were injected intraperitoneally each day with IL-12 (20 ng/g/mouse) and/or IL-18 (200 ng/g/mouse).

RESULTS

Administration of IL-12 and IL-18 to BALB/c-wt mice induced prominent intestinal mucosal inflammation and fatty liver, leading to piloerection, bloody diarrhoea, and weight loss. IL-12 and IL-18 induced striking elevations in serum levels of IFN-gamma that caused NO production, although increased NO had no exacerbating effect on mice. Moreover, iNOS KO mice, or MRL lpr/lpr mice lacking functional Fas were equally susceptible to IL-12 and IL-18. Administration of IL-12 and IL-18 did not induce TNF-alpha production in wild-type mice, and the same treatment to TNF-alpha KO mice induced intestinal mucosal inflammation. Furthermore, they had diffuse and dense infiltration of small fat droplets in their hepatocytes associated with an increase in serum levels of liver enzymes. In contrast, the same treatment in IFN-gamma KO BALB/c mice and iNOS KO mice did not induce these changes.

CONCLUSIONS

Our study strongly indicates that IL-18 together with IL-12 induces intestinal mucosal inflammation in an IFN-gamma dependent but TNF-alpha, NO, and Fas ligand independent manner, and fatty liver is dependent on IFN-gamma and NO.

Spatial distribution and histogenesis of colorectal Paneth cell metaplasia in idiopathic inflammatory bowel disease

BACKGROUND AND AIM

Colorectal Paneth cell metaplasia (PCM) is known to be a sign of idiopathic inflammatory bowel disease (IBD), although its distribution and histogenesis are not fully understood. Objectives of this research were to investigate the spatial distribution of PCM in IBD and other forms of colitis (non-IBD), and to find stimuli causing PCM.

METHODS

We studied multiple biopsy specimens from 181 patients with ulcerative colitis (UC), 159 with Crohn's disease (CD), 448 with non-IBD, and 78 normal controls. Paneth cell metaplasia frequency, at each colorectal site, was evaluated to find possible differences among diseases, phases of activity, and extents of disease.

RESULTS

In non-IBD and controls, PCM was rarely (0-1.9%) seen at distal sites, but frequently (up to 48.7%) found at the ascending colon and cecum (P < 0.001). Paneth cell metaplasia frequency was significantly higher in IBD than in non-IBD patients and controls at distal sites (P < 0.001), but did not differ significantly between UC and CD, or among active, resolving, and quiescent phases. In UC, proctitis and left-sided colitis rarely displayed PCM at unaffected sites. Multiple logistic regression analysis revealed that PCM was positively associated with crypt distortion and mononuclear cell infiltration (P < 0.005), but negatively or not significantly associated with crypt atrophy, mucin depletion, acute inflammation, or phase of activity.

CONCLUSIONS

Paneth cell metaplasia is a non-specific phenomenon in the proximal colon, but distal PCM, which occurs exclusively in affected mucosa, is a useful marker indicating IBD, even in the inactive phase. Regression analysis suggests that repair and regeneration may be the most potent stimuli causing PCM.

CagA seropositivity associated with development of gastric cancer in a Japanese population

BACKGROUND/AIMS

Infection with Helicobacter pylori strains possessing the cagA gene is associated with increased risk of gastric cancer of the intestinal type. The aims of this study were to investigate whether CagA seropositivity is associated with increasing risk of gastric cancer in a Japanese population that has a much higher incidence of gastric cancer than western populations.

METHODS

Eighty one gastric cancer patients and 81 sex and age matched endoscopically evaluated controls were studied. Histologically, 62 cancers were of the intestinal type and 76 were early gastric cancer. Serum CagA IgG antibodies were assayed by enzyme linked immunosorbent assay (ELISA) using purified recombinant CagA protein as antigen. Polymerase chain reaction (PCR) analysis for cagA in H pylori isolates (n = 80) showed that the CagA ELISA had a sensitivity of 83.3% (controls) and 72.5% (cancers).

RESULTS

CagA seropositivity was 60% (49 of 81) in cancer patients and 44% (36 of 81) in controls. The odds ratio for the risk of cancer if CagA seropositive was 1.93 (95% confidence interval (CI) 1.01 to 3.68; p < 0.05). In the 57 H pylori positive cancer patients and their matched H pylori positive controls, the odds ratio for the risk of cancer if CagA seropositive was 2.2 (95% CI 1.04 to 4.65; p < 0.05).

CONCLUSIONS

These results suggest that CagA seropositivity is associated with increased risk of gastric cancer in Japanese populations.

Effect of incorporating low intensity exercise into the recovery period after a rugby match

BACKGROUND

The psychological and physiological condition of athletes affect both their performance in competitions and their health. Rugby is an intense sport which appears to impose psychological and physiological stress on players. However, there have been few studies of the most appropriate resting techniques to deliver effective recovery from a match.

OBJECTIVES

To compare the difference in recovery after a match using resting techniques with or without exercise.

METHODS

Fifteen Japanese college rugby football players were studied. Seven performed only normal daily activities and eight performed additional low intensity exercise during the post-match rest period. Players were examined just before and immediately after the match and one and two days after the match. Blood biochemistry and two neutrophil functions, phagocytic activity and oxidative burst, were measured to assess physiological condition, and the profile of mood states (POMS) scores were examined to evaluate psychological condition.

RESULTS

Immediately after the match, muscle damage, decreases in neutrophil functions, and mental fatigue were observed in both groups. Muscle damage and neutrophil functions recovered with time almost equally in the two groups, but the POMS scores were significantly decreased only in subjects in the low intensity exercise group.

CONCLUSIONS

Rugby matches impose both physiological and psychological stress on players. The addition of low intensity exercise to the rest period did not adversely affect physiological recovery and had a significantly beneficial effect on psychological recovery by enhancing relaxation.

Expression of Interleukin-18, a Th1 cytokine, in human gastric mucosa is increased in Helicobacter pylori infection

Interleukin-18 (IL-18), a cytokine that promotes Th1 responses, is processed to the active mature protein by caspase-1. The effects of Helicobacter pylori infection on gastric IL-18 and caspase-1 were examined. In antral mucosa, IL-18 mRNA expression was greater (P<.01) in H. pylori-positive (n=40) than in H. pylori-negative patients (n=29) with normal mucosa. Inactive precursor (24 kDa) and mature (18 kDa) IL-18 were present in antral biopsy specimens from uninfected and infected subjects. In corpus mucosa, mature IL-18 and a 16-kDa protein, corresponding to inactive IL-18, were present. Active caspase-1 p20 subunit was detected in antral and corpus mucosa of infected and uninfected subjects. These data show that, although H. pylori infection is associated with increased antral IL-18 mRNA expression, mature IL-18 protein and active caspase-1 p20 are present in mucosa of both H. pylori-infected and -uninfected subjects. IL-18 may have an important role in promoting gastric Th1 responses in H. pylori infection.

Guidelines in the management of Helicobacter pylori infection in Japan

BACKGROUND

In preparation of the approval of Helicobacter pylori therapy by the Japanese national health system, the board of directors of the Japanese Society for Helicobacter Research decided to prepare guidelines on the diagnosis and treatment of H. pylori infection for physicians in routine medical practice.

METHODS

A guidelines preparation committee was formed and six meetings were held. Then, in December 1999, a consensus meeting was held in Kobe to obtain the opinions of general practitioners as well as experts from Europe, North America, and Asia.

RESULTS

Helicobacter pylori eradication therapy is recommended in gastric or duodenal ulcer patients. Helicobacter pylori eradication therapy is recommended or gastric mucosa associated lymphoid tissue (MALT) lymphoma but it should be done at specialist institutions. The significance of H. pylori eradication therapy is still under evaluation in patients with hyperplastic polyps, chronic atrophic gastritis, non-ulcer dyspepsia and in patients after endoscopic mucosal resection of gastric cancer and after gastrectomy for gastric cancer. When diagnosing H. pylori infection, at least one of the tests requiring endoscopic biopsy (e.g. rapid urease test, histology, or culture) and tests not requiring biopsy (e.g. measurement of H. pylori antibody or urea breath test) should be used. Multiple tests are recommended to increase the accuracy. The drugs of first choice currently covered by the national health insurance system in Japan are: lansoprazole (30 mg) 1 capsule twice daily, amoxicillin (250 mg) 3 capsules twice daily, and clarithromycin (200 mg) 1-2 tablets twice daily. These three drugs should be administered after breakfast and dinner for 1 week.

CONCLUSION

These guidelines are intended for utilization in routine medical practice after the Japanese national health system begins to cover the management of H. pylori infection.

Increased expression of IL-10 and IL-12 (p40) mRNA in Helicobacter pylori infected gastric mucosa: relation to bacterial cag status and peptic ulceration

AIMS

To investigate interleukin (IL)-12 (p40) and IL-10 mRNA expression levels in the gastric mucosa in relation to H pylori cag status, peptic ulceration, and histopathology.

METHODS

In 81 dyspeptic patients, antral and corpus biopsies were taken for reverse transcriptase polymerase chain reaction (RT-PCR) and histology. G3PDH (control) and IL-10 and IL-12 were coamplified in a duplex PCR and the ratios of cytokines to G3PDH were determined. Bacterial ureA and cagA status was determined by RT-PCR.

RESULTS

IL-10 mRNA expression in both the antral and corpus mucosa was greater (p < 0.01) in cagA positive infection than in H pylori negative patients with histologically normal mucosa. No increase in IL-10 mRNA expression was observed in cagA negative infection. Both in the antral and corpus mucosa, IL-12 mRNA expression was greater (p < 0.05) in cagA positive than in cagA negative infection and uninfected patients with normal gastric mucosa. In cagA positive infection, there was a correlation between IL-10 and IL-12 mRNA expression in both the antral mucosa (r = 0.515, p < 0.01) and the corpus mucosa (r = 0.6, p < 0.005). IL-12 mRNA expression in the antral mucosa was significantly more frequent in H pylori positive patients with duodenal ulcer than in those with gastric ulcer or nonulcer dyspepsia. No difference was observed in IL-10 mRNA expression in relation to endoscopic diagnosis.

CONCLUSIONS

CagA positive H pylori infection is associated with increased IL-10 and IL-12 mRNA expression. The increased expression of IL-12 mRNA in the majority of patients with duodenal ulcer suggests that Th1 responses may predominate and play a role in the pathogenesis of duodenal ulceration.

Functional domains of template-activating factor-I as a protein phosphatase 2A inhibitor

Template-Activating Factor-I (TAF-I) alpha and beta, chromatin remodeling factors, were identified as the stimulatory factor for replication of the adenovirus DNA complexed with viral basic core proteins. Recently, two cellular inhibitors for protein phosphatase 2A (PP2A) have been isolated. One of these inhibitors, designated IPP2A2, is a truncated version of TAF-Ibeta. Here, it is shown using recombinant TAF-I proteins that both TAF-Ialpha and beta have the PP2A inhibitor activity. The N-terminal region but not the C-terminal acidic region, the latter of which is essential for the chromatin remodeling activity, is shown to be required for the PP2A inhibitor activity. Roles of TAF-Ialpha- and beta-specific regions, the C-terminal acidic region, and other regions of TAF-I for the PP2A inhibitor activity are also discussed.

Risk factors for complications after ileocolonic resection for Crohn's disease with a major focus on the impact of preoperative immunosuppressive and biologic therapy: A retrospective international multicentre study

BACKGROUND

Author note: TY, AS, YS, FVT and PGK designed the study. All authors did data collection and gave scientific contribution to the study design and discussion. TY, AS and PGK drafted the article. All authors read and approved the final version of the manuscript.In the era of biologic agents, risk factors for complications following resection for Crohn's disease have not been fully identified. In particular, the association of preoperative use of immunosuppressive and biologic agents with the incidence of complications after resection remains to be elucidated.

AIM

This retrospective multicentre study aimed to identify risk factors for complications after ileocolonic resection for Crohn's disease, with a major focus on the impact of preoperative immunosuppressive and biologic therapy.

METHODS

A total of 231 consecutive patients who underwent ileocolonic resections for active Crohn's disease in seven inflammatory bowel disease referral centres from three countries (Japan, Brazil and Italy) were included. The following variables were investigated as potential risk factors: age at surgery, gender, behaviour of Crohn's disease (perforating vs. non-perforating disease), smoking, preoperative use (within eight weeks before surgery) of steroids, immunosuppressants and biologic agents, previous resection, blood transfusion, surgical procedure (open vs. laparoscopic approach), and type of anastomosis (side-to-side vs. end-to-end). Postoperative complications occurring within 30 days after surgery were recorded.

RESULTS

The rates of overall complications, intra-abdominal sepsis, and anastomotic leak were 24%, 12% and 8%, respectively. Neither immunosuppressive nor biologic therapy prior to surgery was significantly associated with the incidence of overall complications, intra-abdominal sepsis or anastomotic leak. In multivariate analysis, blood transfusion, perforating disease and previous resection were significant risk factors for overall complications (odds ratio [OR] 3.02, 95% confidence interval [CI] 1.21-7.52; P = 0.02), intra-abdominal sepsis (OR 2.67, 95% CI 1.04-6.86; P = 0.04) and anastomotic leak (OR 2.87, 95% CI 1.01-8.18; P = 0.048), respectively.

CONCLUSIONS

Blood transfusion, perforating disease and previous resection were significant risk factors for overall complications, intra-abdominal sepsis and anastomotic leak after ileocolonic resection for Crohn's disease, respectively. Preoperative immunosuppressive or biologic therapy did not increase the risk of postoperative complications.

Neural substrates participating in acquisition of facial familiarity: an fMRI study

The amygdala is related to recognition of faces and emotions, and functional magnetic resonance imaging (fMRI) studies have reported that the amygdala is habituated over time with repetition of facial stimuli. When subjects are presented repeatedly with unfamiliar faces, they come to gradually recognize the unfamiliar faces as familiar. To investigate the brain areas participating in the acquisition of familiarity to repeatedly presented unfamiliar faces, we conducted an fMRI study in 16 healthy subjects. During the task periods, the subjects were instructed to see presented unfamiliar faces repeatedly and to judge whether the face was male or female or whether the face had emotional valences. The experiment consisted of nine sessions. To clarify the brain areas that showed increasing or decreasing activation as the experimental session proceeded, we analyzed the fMRI data using specified linear covariates in the face recognition task from the first session to the ninth session. Imaging data were investigated on a voxel-by-voxel basis for single-group analysis according to the random effect model using Statistical Parametric Mapping. The bilateral posterior cingulate cortices showed significant increases in activity as the experimental sessions proceeded, while the activation in the right amygdala and the left medial fusiform gyrus decreased. Thus, the posterior cingulate cortex may play an important role in the acquisition of facial familiarity.

The endotoxin of Helicobacter pylori is a modulator of host-dependent gastritis

Atrophic gastritis caused by Helicobacter pylori is the precursor lesion in the development of intestinal-type gastric adenocarcinoma. In animal models, atrophic gastritis induced by Helicobacter felis has been shown to be host dependent, developing in some mouse strains and not in others. The lipopolysaccharide (LPS) of H. pylori has been suggested to play a role in the induction of gastritis. The goal of this study was to compare the inflammation induced by long-term infection of the C3H/He and the C3H/HeJ strains of mice with H. felis. C3H/HeJ mice are unresponsive to LPS. Six months after infection, severe atrophic gastritis had developed in the body mucosae of all infected C3H/He mice, with replacement of parietal and chief cells. Atrophy was associated with a loss of the H. felis from the antral mucosa. In contrast, no atrophy was seen in the infected C3H/HeJ non-LPS responder animals, and heavy colonization of the antrum remained. There were no significant differences between both the quantitative and qualitative serum immunoglobulin G (IgG) and salivary IgA levels in both strains of mice. The main difference between the two strains of long-term-infected mice was a lack of macrophage infiltration in the lamina propria. Immunization induced good protective immunity to challenge with viable H. felis. Helicobacter-induced, host-dependent gastritis is likely to be cell mediated. The C3H/He and C3H/HeJ mouse model provides an excellent opportunity to investigate the cellular basis of atrophic gastritis.

Leukocytapheresis with leukocyte removal filter as new therapy for ulcerative colitis

Leukocytapheresis (LCAP) with a leukocyte removal filter column was administered for 45 patients with ulcerative colitis (UC). We evaluated changes in the leukocyte count and the differential percentages during LCAP. Cytokine production was assessed from each patient's peripheral mononuclear cells or monocytes. Flow cytometry was performed to assess the removal rates of activated cells and adhesion molecule positive cells by LCAP. Clinical improvement was recognized in 35 of 45 patients during intensive LCAP therapy, and it continued throughout maintenance therapy in 32 patients (71.1%). The leukocyte count was decreased to about 40% during the first 30 min, but it increased to approximately 170% at 20 min after the completion of LCAP. The concentration of tumor necrosis factor (TNF)alpha before LCAP in the effective group was higher than it was in either the ineffective group or the control group. Its level decreased to near normal range after LCAP. In the effective group, the concentrations of interleukin (IL)-1beta, IL-2, interferon (IFN)gamma, and IL-8 were near the normal upper limits before LCAP; however, they had decreased after LCAP. The concentration of IL-4 increased after LCAP. In the ineffective group, in contrast, the concentrations had been at or near normal before the initial LCAP treatment. Flow cytometry study revealed that LCAP could remove the activated cells and adhesion molecule positive cells more effectively. The clinical improvement and the changes observed before and after LCAP therapy suggest that LCAP is able to intervene in the causal mechanism(s) of UC.

Monoclonal antibodies against the native urease of Helicobacter pylori: synergistic inhibition of urease activity by monoclonal antibody combinations

Monoclonal antibodies (MAbs) against the native urease of Helicobacter pylori NCTC 11637 were found to clearly inhibit the urease activity. Interestingly, synergistic inhibition by two MAbs recognizing different subunits was also observed. Ten MAbs were produced and classified as two isotypes of the immunoglobulin G (IgG) subclass, IgG1, and IgG2a. Western blot (immunoblot) analysis using sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that five MAbs recognized the large subunit and the other five recognized the small subunit of the urease. Among the MAbs, L2 and S2, which recognized the large and the small subunits, respectively, were also able to inhibit the urease activity of clinical isolates from H. pylori-infected patients. The combination of L2 and S2 led to augmented synergistic inhibition. L2, but not S2, could also inhibit the urease activity from Helicobacter mustelae; enzyme-linked immunosorbent assay and Western blot analysis showed that L2 cross-reacted with this urease. These results suggested that the epitope recognized by L2 had a structure common to both Helicobacter species and may be involved in the active site of the urease. In contrast to the MAbs, a polyclonal antibody in sera from mice immunized with H. pylori urease did not have the ability to inhibit H. pylori urease activity. However, the polyclonal antibody retained the ability to abolish the inhibitory action of these MAbs. Moreover, other MAbs which could not inhibit H. pylori urease activity also abolished the inhibitory action.

Immunobiological activities of chemically defined lipid A from Helicobacter pylori LPS in comparison with Porphyromonas gingivalis lipid A and Escherichia coli-type synthetic lipid A (compound 506)

Helicobacter pylori lipid A, characterised by a glucosamine beta (1-6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2- and 2'-positions, respectively, exhibited no or very low endotoxic activities, i.e. lethal toxicity in galactosamine-loaded mice, pyrogenicity for rabbits and the activity of the Limulus test compared with Escherichia coli-type synthetic lipid A (compound 506), which possesses beta-(1-6)-linked glucosamine disaccharide 1,4'-bisphosphate, with two acyloxyacyl groups at the 2'- and 3'-positions and two 3-hydroxytetradecanoyl groups at the 2- and 3-positions. The endotoxic properties of H. pylori lipid A were also a little weaker than those of the low endotoxic lipid A of P. gingivalis, which has 1-phospho beta-(1-6)-linked glucosamine disaccharide with 3-hydroxy-15-methylhexadecanoyl and 3-hexadecanoyloxy-15-methylhexadecanoyl groups at the 2- and 2'-positions, respectively. Further, the mitogenic activity of H. pylori lipid A in murine splenic mononuclear cells was also less than those of P. gingivalis lipid A and compound 506. However, H. pylori lipid A induced comparable production of interleukin-6 (IL-6) by human peripheral blood mononuclear cells (PBMC) compared with P. gingivalis lipid A and compound 506. H. pylori lipid A also increased human natural killer cell activity, and strongly agglutinated rabbit erythrocytes. However, the lipid As of H. pylori and P. gingivalis showed lower activities in inducing tumour necrosis factor alpha (TNF-alpha) production by human PBMC and IL-8 production by human gingival fibroblasts than that of compound 506. The structural feature of H. pylori lipid A may be associated with low endotoxic properties and potent immunobiological activities.

Helicobacter pylori infection increases mucosal permeability of the stomach and intestine

It is important to study the effect of Helicobacter pylori infection on the permeability of the intestine. Permeability was evaluated by oral sucrose tolerance test using sucrose 25 g in 200 ml of water. Existence of H. pylori itself was associated with increased permeability of sucrose. Also, the permeability of sucrose increased as polymorphonuclear and lymphocyte infiltration increased. The increase of mucosal permeability suggests that antigens like protein penetrate into the body and result in systemic reactions. Thus, it is important to study the implication of increased permeability in relation not only to gastric diseases but also certain systemic diseases.

Chemical structure of lipid A from Helicobacter pylori strain 206-1 lipopolysaccharide

The chemical structure of a novel lipid A, which was obtained as a major component from lipopolysaccharide of Helicobacter pylori strain 206-1, was determined to be a glucosamine beta(1-6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2- and 2'-position, respectively. The absence of a phosphoryl group at the 4'-position and fatty acyl groups at the 3- and 3'-position, and the stoichiometric presence of 2-aminoethyl phosphate at the 1-position are unique features, distinguishing it from the lipid A of enterobacteria.

Biopsy pathology predicts patients with ulcerative colitis subsequently requiring surgery

BACKGROUND

The clinical course of patients with ulcerative colitis (UC) is unpredictable, and 17%-38% ultimately require surgery. We hypothesized that mucosal histology may differ between patients requiring surgery and those receiving medication alone. The aim of this study was to elucidate comprehensive criteria consisting of specific histologic features enabling the prediction of failure to medical treatment.

METHODS

We studied colorectal biopsy specimens from 67 patients ultimately requiring surgery (UC-S) and 90 receiving medication alone for more than 3 years (UC-M), and conducted multiple logistic regression analysis on 70 histologic features together with endoscopic disease extent and patient age. The analysis constructed an equation finding probability of UC-S (P(UC-S)). Based on a receiver-operating characteristic curve, we selected four cut-off values of P(UC-S), and determined criteria of five categories: highest-risk, higher-risk, unpredictable, lower-risk and lowest-risk of surgery. Sensitivity and specificity of criteria were evaluated in a 2 x 5 table.

RESULTS

Statistically significant features predicting UC-S were deep ulceration (X1), frequent crypt abscesses (X2), focal and segmental mononuclear cell infiltration (X3 and X4), paucity of eosinophils (X5: eosinophil infiltration) and wide extent of the disease (X6). The regression equation was as follows: logitP(UC-S) = -16.26 + 3.20X1 + 4.83X2 + 11.65X3 + 5. 10X4 - 5.59X5 + 5.53X6. Higher-risk and lower-risk showed sensitivity exceeding 91.0% and specificity exceeding 98.5% in predicting the outcome.

CONCLUSIONS

Our criteria incorporating specific histologic features and endoscopic disease extent reliably predict eventual clinical outcome, and are expected to prove useful in determining the necessity of surgery.

Helicobacter pylori in oral ulcerations

Helicobacter pylori is an important pathogen involved in the development of gastrointestinal ulcers, but its involvement in oral ulcerous lesions is unclear. As culture is generally recognized as the gold standard for diagnosis of H. pylori infection, we employed this approach to assess the association of H. pylori with oral mucosal ulcerations. Samples were collected from patients with oral mucosal ulcerative disorders: 12 cases of recurrent aphthous stomatitis (RAS), 7 cases of herpes simplex virus (HSV) stomatitis, and 3 cases of erosive lichen planus (LP). Serum IgG antibodies against H. pylori were examined in all cases. All of the RAS and erosive LP cases were culture-negative for H. pylori, while two cases of HSV stomatitis were positive. The two culture-positive cases were also seropositve for the H. pylori antigen. It is suggested that H. pylori might not have a direct association with oral ulcerations. However, H. pylori in the oral cavity might exist in a non-culturable coccoid state without productive infection, and might form colonies only under special conditions such as HSV infection.