The Anti-Inflammatory Effect of Sulforaphane in Mice with Experimental Autoimmune Encephalomyelitis

BACKGROUND

Multiple sclerosis (MS) is an immune-associated inflammatory disorder of the central nervous system and results in serious disability. Although many disease-modifying therapy drugs have been developed, these drugs have shown limited clinical efficacy and some adverse effects in previous studies, therefore, there has been reasonable need for less harmful and cost-effective therapeutics. Herein, we tested the anti-inflammatory effect of sulforaphane (SFN) in a mouse model of experimental autoimmune encephalomyelitis (EAE).

METHODS

The EAE mice were randomly assigned into two experimental groups: the phosphate-buffered saline (PBS)-treated EAE group and SFN-treated EAE group. After EAE mice induction by auto-immunization against the myelin oligodendrocyte glycoprotein peptide, we evaluated EAE symptom scores and biochemical analyses such as infiltration of inflammatory cells and demyelination of the spinal cord. Furthermore, western blotting was performed using the spinal cords of EAE mice.

RESULTS

In the behavioral study, the SFN-treated EAE mice showed favorable clinical scores compared with PBS-treated EAE mice at the 13th day (1.30 ± 0.15 vs. 1.90 ± 0.18; P = 0.043) and 14th day (1.80 ± 0.13 vs. 2.75 ± 0.17; P = 0.003). Additionally, the biochemical studies revealed that SFN treatment inhibited the inflammatory infiltration, demyelinating injury of the spinal cords, and the up-regulation of inducible nitric oxide synthase in the EAE mice.

CONCLUSION

The SFN treatment showed anti-inflammatory and anti-oxidative effects in the EAE mice. Conclusively, this study suggests that SFN has neuroprotective effects via anti-inflammatory processing, so it could be a new therapeutic or nutritional supplement for MS.

Characteristics of South Korean Patients with Hereditary Transthyretin Amyloidosis

Background and Purpose

This retrospective cross-sectional study included 18 patients from unrelated families harboring mutations of the transthyretin gene (TTR), and analyzed their characteristics and geographical distribution in South Korea.

Methods

The included patients had a diagnosis of systemic amyloidosis, clinical symptoms, such as amyloid neuropathy or cardiomyopathy, and confirmation of a TTR gene mutation using genetic analysis recorded between April 1995 and November 2014.

Results

The mean age at disease onset was 49.6 years, and the mean disease duration from symptom onset to diagnosis was 3.67 years. Fifteen of the 18 patients were classified as mixed phenotype, 2 as the neurological phenotype, and only 1 patient as the cardiac phenotype. The most-common mutation pattern in South Korea was Asp38Ala, which was detected in eight patients. Thirteen patients reported their family hometowns, and five of the eight harboring the Asp38Ala mutation were from the Gyeongsang province in southeast Korea. The other eight patients exhibited a widespread geographical distribution. A particularly noteworthy finding was that the valine at position 30 (Val30Met) mutation, which was previously reported as the most-common TTR mutation worldwide and also the most common in the Japanese population, was not detected in the present South Korean patients.

Conclusions

South Korean patients with hereditary TTR amyloidosis exhibited heterogeneous TTR genotypes and clinical phenotypes. The findings of this study suggest that the distribution of TTR amyloidosis in South Korea is due to de novo mutations and/or related to the other countries in East Asia.

Epidemiology and Clinical Characteristics of Zika Virus Infections Imported into Korea from March to October 2016

Zika is a re-emerging, mosquito-borne viral infection, which has been recently shown to cause microcephaly and Guillain-Barré syndrome. Since 2015 the number of infected patients has increased significantly in South America. The purpose of this study was to identify the epidemiologic and clinical characteristics of patients with Zika virus (ZIKV) infections in Korea. Patients who had visited areas of risk and tested positive in the ZIKV reverse transcriptase polymerase chain reaction (RT-PCR) in blood, urine, or saliva specimens were included. The first Korean case of ZIKV infection was reported in March 2016, and 14 cases had been reported by October 2016. The median age of the patients was 34 years (19-64 years). Ten patients had been exposed in Southeast Asia and 4 in Latin America. Rash was the most common symptom (92.9%; 13/14), followed by myalgia (50.0%; 7/14), and arthralgia (28.6%, 4/14). There were no neurologic abnormalities and none of the patients was pregnant. Results of biochemical tests were normal. Positivity rates of RT-PCR for ZIKV in serum, urine, and saliva were 53.8%, 100.0%, and 83.3%, respectively in the first week of symptoms. In conclusion, 14 patients with ZIKV infections were reported in Korea by October 2016 and all of them had mild clinical symptoms.

The Anti-Inflammatory Effects of Oral-Formulated Tacrolimus in Mice with Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is a T-lymphocyte-mediated autoimmune disease that is characterized by inflammation in the central nervous system (CNS). Although many disease-modifying therapies (DMTs) are presumed effective in patients with MS, studies on the efficacy and safety of DMTs for preventing MS relapse are limited. Therefore, we tested the immunosuppressive anti-inflammatory effects of oral-formulated tacrolimus (FK506) on MS in a mouse model of experimental autoimmune encephalomyelitis (EAE). The mice were randomly divided into 3 experimental groups: an untreated EAE group, a low-dose tacrolimus-treated EAE group, and a high-dose tacrolimus-treated EAE group. After autoimmunization of the EAE mice with myelin oligodendrocyte glycoprotein, symptom severity scores, immunohistochemistry of the myelination of the spinal cord, and western blotting were used to evaluate the EAE mice. After the autoimmunization, the symptom scores of each EAE group significantly differed at times. The group treated with the larger tacrolimus dose had the lowest symptom scores. The tacrolimus-treated EAE groups exhibited less demyelination and inflammation and weak immunoreactivity for all of the immunization biomarkers. Our results revealed that oral-formulated tacrolimus inhibited the autoimmunization in MS pathogenesis by inactivating inflammatory cells.

Reference Range of Respiratory Muscle Strength and Its Clinical Application in Amyotrophic Lateral Sclerosis: A Single-Center Study

Background and Purpose

Evaluating respiratory function is important in neuromuscular diseases. This study explored the reference ranges of the maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP) in healthy adults, and applied them to amyotrophic lateral sclerosis (ALS) patients.

Methods

MIP, MEP, and SNIP were measured in 67 healthy volunteers aged from 21 to 82 years. Reference ranges were evaluated by multivariate regression analysis using the generalized additive modeling of location, scale, and shape method. Thirty-six ALS patients were reviewed retrospectively, and abnormal values of MIP, MEP, and SNIP were determined according to the reference ranges.

Results

MIP, MEP, and SNIP were abnormal in 57.1%, 51.4%, and 25.7% of the ALS patients, respectively. MIP and SNIP were significantly correlated with the degree of restrictive pattern and respiratory symptoms. The ALS Functional Rating Scale-Revised score was correlated with SNIP.

Conclusions

This study has provided the reference range of respiratory muscle strength in healthy adults. This range is suitable for evaluating respiratory function in ALS patients.

Hydrogel coated mesh decreases tissue reaction resulting from polypropylene mesh implant: implication in hernia repair

PURPOSE

Use of polypropylene mesh (PPM) in hernia repair is associated with tissue reactivity. We examined, in a rat model, a novel non-biodegradable hydrogel coated PPM which may allow for decreased inflammation and a decreased foreign body reaction.

METHODS

Through a dorsal midline incision, a 2 cm × 2 cm section of PPM (either coated or uncoated) was placed on the fascial surface 1.5 cm from the incision on the dorsal wall of Sprague-Dawley rats. At 2 and 12 weeks after placement, the PPM and surrounding tissue were harvested. A board-certified dermatopathologist examined H&E stained slides for fibrosis and foreign body reaction. In addition, tissues were stained for apoptotic cells, oxidative damage, macrophages, fibroblasts, neovascularization and metalloproteases.

RESULTS

At 2 and 12 weeks, there was a greater than 95 % decrease in foreign body giant cells in coated PPM samples compared to uncoated; fibrosis was decreased by 50 %. At 2 and 12 weeks, oxidative damage, fibroblast accumulation, apoptosis and macrophages were significantly decreased in coated PPM samples compared to uncoated PPM.

CONCLUSION

These results demonstrate that a non-biodegradable hydrogel coating of PPM led to significant reduction in foreign body reaction, oxidative stress and apoptosis compared to uncoated PPM in vivo, and suggest that this coating could be clinically useful in hernia repair.

Copy number variations of HLA-I and activation of NKp30 pathway determine the sensitivity of gastric cancer cells to the cytotoxicity of natural killer cells

Nude mice are important in vivo model for characterization of cell malignancy behavior; however, many cancer cells fail to form tumors in it. Understanding this defective mechanism may provide novel insights into tumorigenesis and how tumor cells escape innate immunity. Whole-genome sequencing was conducted on two gastric cancer (GC) cells, BGC823 and AGS, which do and do not form tumors in nude mice, to identify their genomic differences relevant to natural killer (NK) cells. We found that the tumorigenic capacity of human GC cell lines was dependent on the recruitment and activation of NK cells in xenograft tumors. We used whole-genome sequence (WGS) on GC cell lines to identify potential genes controlling susceptibility to NK-mediated killing. The tumorigenic cell line BGC823 expressed high levels of HLA-I because of copy gain and was resistant to NK cell killing. In contrast, another cell line AGS expressing low levels of HLA-I with activated NKp30/MAPK/IL-12 (interleukin-12) or IL-2 (interleukin-2) pathway was susceptible to NK lysis. Treatment of tumor bearing mice with systemic administration of IL-12 in combination with intratumor injection of anti-HLA-I antibody significantly increased NK cell recruitment into xenograft tumors, which became sensitive to NK killing, resulting in reduced tumor progression. In human GC specimens, decreased HLA-I expression and increased NK cells surrounding tumor cells were correlated with decreased metastasis potential and better prognosis of patients. Our results provide a mechanistic basis for GC cells to escape NK lysis and a promising prospect of NK immunotherapy for GC cells.

Colon capsule endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

PillCam colon capsule endoscopy (CCE) is an innovative noninvasive, and painless ingestible capsule technique that allows exploration of the colon without the need for sedation and gas insufflation. Although it is already available in European and other countries, the clinical indications for CCE as well as the reporting and work-up of detected findings have not yet been standardized. The aim of this evidence-based and consensus-based guideline, commissioned by the European Society of Gastrointestinal Endoscopy (ESGE) is to furnish healthcare providers with a comprehensive framework for potential implementation of this technique in a clinical setting.

Clinical performance examination utilizing standardized patients in board examination: based on the board examination of korean neurological association for three years

PURPOSE

Evaluation of clinical skills and attitude including development of dynamic patient-doctor relationship is important in board examination (BE). Korean Neurological Association (KNA) has introduced clinical performance examination (CPX) utilizing standardized patients (SP) to BE in 2007. In this study, the authors describe the 3-year experience of CPX in BE through 2009.

METHODS

To implement CPX session in BE, KNA developed CPX workshop for BE attendees and members of grading committee. CPX sessions in BE consisted of two model scenarios mimicking neurological patients in clinical practice. The total score and itemized scores of CPX sessions were compared with other areas of BE, and scores from each year were also compared.

RESULTS

Scores from CPX sessions were significantly correlated with BE step II. Among the itemized scores of CPX sessions, clinical items including history taking and physical examination were significantly correlated with scores from other areas of BE. However, scores from global assessment from SP were strongly associated with patient-doctor relationship, history taking, and patient education.

CONCLUSION

Our experiences suggest that CPX utilizing SP is a useful tool to assess the clinical skills in BE. In order to produce clinically well qualified neurologists, more efforts should be made to develop cases and to improve assessment tools for CPX.

Sjögren’s syndrome myelopathy: spinal cord involvement in Sjögren’s syndrome might be a manifestation of neuromyelitis optica

Objective

To evaluate clinical characteristics, aquaporin (AQP)-4 antibody results, and probability of developing symptoms of neuromyelitis optica (NMO) in patients with Sjögren’s syndrome myelopathy (SSM).

Methods

We identified eight patients with spinal cord involvement from 112 patients with Sjögren’s syndrome (SS) referred to the neurology department. The clinical characteristics and AQP-4 antibody status, based on immunoprecipitation of EGFP-tagged AQP-4, of the patients with SSM were assessed.

Results

All patients with SSM had extensive spinal cord lesions, high mean annual relapse rates, and poor response to steroid treatment. Of the eight patients with SSM, seven patients satisfied the revised diagnostic criteria for NMO or showed positive results from AQP-4 antibody testing; one patient had incomplete follow-up. The clinical manifestations and AQP-4 autoantibody status of patients with SSM did not differ significantly from those of NMO patients without SS.

Conclusion

All patients with SSM had poor prognosis with high mean annual relapse rates, and most seemed to have the clinical and immunological characteristics of NMO. Early aggressive immune therapies should be considered in patients with SSM irrespective of the presence or absence of optic neuritis.

Brain abnormalities in Sjogren syndrome with recurrent CNS manifestations: association with neuromyelitis optica

Background and objectives

Optic neuritis or longitudinally extensive myelitis in Sjogren syndrome (SS) suggests a neuromyelitis optica spectrum disorder (NMOSD). However, brain abnormalities of SS remain to be elucidated for the association with neuromyelitis optica (NMO).

Methods

Twelve primary SS patients (all women, 42 ± 13.2 years) who had recurrent central nervous system (CNS) manifestations with brain involvement were retrospectively identified. Brain MRI, and neurologic and serologic findings were analyzed with the measurement of anti-aquaporin-4 antibody (AQP4-Ab).

Results

All patients showed brain lesions characteristic of NMO as follows: 1) the involved sites adjacent to the third and fourth ventricles and in the posterior limb of the internal capsule, 2) unique configurations, such as the longitudinal course from the internal capsule to the midbrain, large cerebral or cerebellar lesions over 3 cm, and cavity-like formations. AQP4-Ab was positive in six of eight patients tested, and all the seropositive patients showed lesions with increased diffusion, suggestive of vasogenic edema. Four patients met the revised criteria of NMO, and nine had features of NMOSDs. Of the remaining three patients showing only brain involvement, one had AQP4-Ab.

Conclusions

This study demonstrates that SS patients with recurrent CNS involvement have brain abnormalities characteristic of NMO and AQP4-Ab in Korea. The presence of AQP4-Ab in one SS patient with only brain involvement may suggest that the coexistence of NMO should be explored in SS patients with recurrent CNS manifestations, even without optic neuritis or myelitis.

Trans-cutaneous electrogastrographic study of gastric myoelectric activity in transposed intrathoracic stomach after esophagectomy

We examined the feasibility of trans-cutaneous electrogastrography (EGG) in recording myoelectric activity of the transposed thoracic stomach after esophagectomy. Nineteen patients who had Ivor-Lewis esophagectomy were studied. The EGG signal was recorded using cutaneous electrodes placed over the lower sternum. Eleven patients who underwent total gastrectomy served as controls. Normal rhythm pattern (2.4-3.6 cpm > or = 70%) and power ratio (PR > or = 2) was observed in five and 12 patients, respectively, after esophagectomy. The observation of normal gastric rhythm was more frequent in the postprandial period in the esophagectomy group (median 42.6%vs. 7.4%, P = 0.01), and the PR was significantly higher (median 2.27 vs. 1.38, P = 0.013) than the gastrectomy group. Feeding further increased the prevalence of normal gastric slow wave in the esophagectomy group (median 14.8% to 42.6%, P = 0.002) and improved the stability of dominant frequency (median 78% to 67%, P = 0.015). We conclude that gastric myoelectric activities of thoracic transposed stomach can be detected from cutaneous sternal electrodes. This represented a preservation of gastric motility even when the stomach is pulled up to the thorax as a substitute for the esophagus.

Clinical utility of trapezius muscle studies in the evaluation of amyotrophic lateral sclerosis

Needle electromyography (EMG) and determining the motor evoked potential (MEP) of the genioglossus (tongue) are difficult to perform in evaluation of the craniobulbar region in patients with amyotrophic lateral sclerosis (ALS). Needle EMG and MEP determination in the upper trapezius were carried out in 17 consecutive ALS patients. The needle EMG parameters recorded included abnormal spontaneous activity and motor unit action potential morphology. An upper motor neuron lesion was presumed when either response to cortical stimulation was absent, or the central conduction time was delayed (>mean + 2 SD). Of the 12 patients with limb-onset ALS, using needle EMG, 11 were found to have abnormalities in the upper trapezius, and only five in the tongue. Three of the six patients with isolated limb involvement had abnormal MEP findings. In conclusion, electrophysiological studies of the upper trapezius are useful in ALS patients without bulbar symptoms.

MuSK antibody-positive, seronegative myasthenia gravis in Korea

Several reports from Western countries suggest differences in the clinical features of patients with muscle specific kinase (MuSK) antibody-positive and -negative seronegative myasthenia gravis (MG). We performed the first survey in Korea of MuSK antibodies, studying 23 patients with acetylcholine receptor (AChR)-antibody seronegative MG. MuSK antibodies were present in 4 (26.7%) of 15 generalized seronegative MG patients and none of 8 ocular seronegative MG patients. All four MuSK positive patients were females, with pharyngeal and respiratory muscle weakness, and required immunosuppressive treatment. However, overall disease severity and age at onset was similar to that of MuSK-negative MG and treatment responses were equally good.

Accuracy of endoscopic ultrasonography in diagnosing ascites and predicting peritoneal metastases in gastric cancer patients

BACKGROUND

Preoperative diagnosis of peritoneal metastases (PM) is difficult in patients with gastric cancer (GC).

AIMS

To assess the accuracy of endoscopic ultrasonography (EUS) in diagnosing ascites and its predictability for the presence of PM in GC patients.

SUBJECTS

Consecutive patients with newly diagnosed GC from 1998 to 2004 were studied.

METHODS

All patients underwent EUS, ultrasound (US), and computed tomography (CT) scan for preoperative staging and the presence of ascites. The results were compared with operative findings. The diagnosis of PM was confirmed by histopathology or peritoneal fluid cytology.

RESULTS

A total of 301 patients were recruited and in 250 patients the presence of ascites (n = 93) and PM (n = 71) were confirmed. EUS was more sensitive (87.1%) than combined US and CT scan examinations (16.1%) and operative findings (laparoscopy or laparotomy) (40.9%) in diagnosing ascites. Sensitivity, specificity, positive and negative predictive values, and accuracy for predicting the presence of PM were 73%, 84%, 64%, 89%, and 81% by EUS; 18%, 99%, 87%, 75%, and 76% by combining US and CT scan; and 77%, 94%, 83%, 91%, and 89% by operative findings, respectively. In multivariate logistic regression analysis, EUS detected ascites was the only significant independent predictor for the presence of PM (p<0.001; odds ratio 4.7 (95% confidence interval 2.0-11.2)).

CONCLUSION

EUS is a sensitive method for diagnosing ascites which is an important predictive factor for the presence of PM in GC patients.

Comparison of two new rapid serology tests for diagnosis of Helicobacter pylori infection in Chinese patients

BACKGROUND

Rapid serology test is a simple and convenient way for diagnosing Helicobacter pylori infection. However performances of these tests are usually less satisfactory than expected, particularly in developing countries.

AIM

To evaluate the performances of two newly developed rapid serology tests for Helicobacter pylori infection.

PATIENTS

Consecutive Chinese dyspeptic patients undergoing upper gastrointestinal endoscopy.

METHODS

Gastric biopsies were obtained from antrum and corpus for rapid urease test and histological examination. Diagnosis of Helicobacter pylori infection was based on two or more positive results in rapid urease test, histology and [13C] urea breath test. Patients' sera were tested against two rapid serology tests: ASSURE Hp Rapid Test (Genelabs Diagnostics, Singapore) and SureStep (Applied Biotech, San Diego, CA, USA).

RESULTS

A total of 148 patients were evaluated and Helicobacter pylori infection was diagnosed in 78 (53%) patients by gold standard. The sensitivities of ASSURE Hp and SureStep were, respectively, 94% and 71% (p=0.0003). Specificities of the two test kits were both 90%. The overall accuracy of ASSURE Hp was significantly higher than SureStep (92% versus 80%, p=0.004).

CONCLUSION

Both rapid serology tests appear to be specific in diagnosing Helicobacter pylori infection in the Chinese populations. However the ASSURE Hp test is more sensitive and accurate than the SureStep test.

Alterations of frizzled (FzE3) and secreted frizzled related protein (hsFRP) expression in gastric cancer

Wnt signaling pathway is important for development and carcinogenesis. Alterations of this pathway, such as mutations in adenomatous polyposis coli (APC) gene and activation mutations of beta-catenin, would result in stabilization of beta-catenin and subsequent translocation to nucleus where genes are transcribed. Recently, a receptor of Wnt, FzE3 was found to be up-regulated in esophageal carcinoma while a non-receptor antagonist of Wnt, secreted frizzled related protein (hsFRP) was found to be down-regulated in some cancer. These findings suggested that FzE3 is a potential oncogene while hsFRP is a potential tumor suppressor gene. We aimed to investigate whether FzE3 and hsFRP were altered in gastric cancer. Twelve cases of gastric cancer, including 7 cases of intestinal type, 4 cases of diffuse type and I case of mixed type, were studied. FzE3 and hsFRP mRNAs were expressed in most of the paired normal gastric tissues. FzE3 was over-expressed in 9 cases (75%) of gastric carcinoma tissues while hsFRP was down-regulated in 2 cases (16%). Beta-catenin nuclear staining was identified in 3 cases (27%) and cyclin D1 was expressed in 5 cases (41%) of cancer samples. All these cases were associated with either up-regulation of FzE3 or down-regulation of hsFRP. Our results suggested that alterations of FzE3 or hsFRP were frequent in gastric cancer. These provide alternative mechanisms leading to activation of Wnt signaling pathway in gastric carcinogenesis.

The efficacy of thymosin in the treatment of chronic hepatitis B virus infection: a meta-analysis

BACKGROUND

Trials of thymosin treatment in chronic hepatitis B virus infection have been small and the results have been inconsistent.

AIM

To conduct a meta-analysis to evaluate the efficacy of thymosin treatment in chronic hepatitis B virus infection.

METHODS

Randomized controlled trials comparing thymosin for over 24 weeks vs. placebo (or usual care) in the treatment of chronic hepatitis B virus infection were identified through MEDLINE, EMBASE and the Cochrane Register of Clinical Trials. Biochemical (normalization of transaminases) and virological (loss of hepatitis B virus DNA and hepatitis B e antigen) responses were analysed using the intention-to-treat method. The odds ratio was used to measure the magnitude of the efficacy.

RESULTS

Five trials (353 patients) were identified. The odds ratio (95% confidence interval) of the virological response of thymosin over placebo at the end of treatment, 6 months post-treatment and 12 months post-treatment were 0.56 (0.2-1.52), 1.67 (0.83-3.37) and 2.67 (1.25-5.68), respectively. There was an increasing trend of the virological response with time since the cessation of thymosin treatment (P=0.02). There was no difference in the biochemical response between the thymosin and placebo groups at the end of treatment, 6 months post-treatment and 12 months post-treatment.

CONCLUSIONS

Thymosin is effective in suppressing viral replication in chronic hepatitis B virus infection, but the effect is delayed until 12 months after the cessation of treatment.

Dysfunction of oesophageal motility in Helicobacter pylori-infected patients with reflux oesophagitis

BACKGROUND

Helicobacter pylori infection has been suggested to be protective against gastro-oesophageal reflux disease. However, a significant proportion of patients with gastro-oesophageal reflux disease are infected by H. pylori.

AIM

To study oesophageal motor function in H. pylori-infected patients with reflux oesophagitis.

METHODS

Patients with erosive reflux oesophagitis were recruited prospectively for stationary oesophageal manometry and 24-h ambulatory oesophageal pH monitoring. H. pylori status was determined by biopsy urease test. Non-reflux volunteers were recruited as controls.

RESULTS

Seventy-four patients with erosive oesophagitis (34 H. pylori-positive, 40 H. pylori-negative) and 48 non-reflux patient controls (22 H. pylori-positive, 26 H. pylori-negative) were recruited. There was no difference in severity of oesophagitis (median grade, 1; P=0.53) or oesophageal acid exposure (total percentage time oesophageal pH < 4, 7.6% vs. 6.8%; P=0.57) between H. pylori-positive and H. pylori-negative groups. Compared to H. pylori-negative patients, H. pylori-positive patients had significantly lower basal lower oesophageal sphincter pressure (12.2 mmHg vs. 15.3 mmHg; P=0.03) and amplitude of distal peristalsis (56.9 mmHg vs. 68.4 mmHg; P=0.03). Ineffective oesophageal motility (14% vs. 7%; P=0.02) and failed oesophageal peristalsis were also significantly more prevalent in H. pylori-positive patients.

CONCLUSIONS

Among patients with a similar degree of reflux oesophagitis, H. pylori-infected patients have more severe oesophageal dysmotility and lower oesophageal sphincter dysfunction. Oesophageal motor dysfunction probably plays a dominant role in the development of gastro-oesophageal reflux disease in patients with H. pylori infection.

Lamivudine treatment for fulminant hepatic failure due to acute exacerbation of chronic hepatitis B infection

BACKGROUND

Exacerbation of chronic hepatitis B infection can lead to fulminant hepatic failure with a mortality of up to 90%.

AIM

To evaluate the efficacy of lamivudine in the treatment of this subgroup of patients.

METHODS

Twenty-four patients with exacerbation of chronic hepatitis B infection and fulminant hepatic failure were treated with lamivudine, 100 mg daily. Hepatitis A, C, D and human immunodeficiency virus co-infections and hepatocellular carcinoma were excluded.

RESULTS

The median age was 53 years (range, 24-77 years) with a male predominance of 20:4. Seventeen patients were hepatitis B e antigen positive. Mean hepatitis B virus DNA was 2079 Meq/mL. Eight patients (33%) survived (group A). Thirteen patients died and three patients received liver transplantation (67%) (group B). Baseline laboratory results were comparable between the two groups, including serum albumin, bilirubin, alanine aminotransferase, prothrombin time and creatinine. Group B patients had significantly more comorbid illnesses at baseline and more complications, including sepsis and renal failure, compared with group A patients. Six out of eight survivors (75%) had full hepatitis B e antigen seroconversion, but this was not sustained in four patients.

CONCLUSIONS

Lamivudine may be useful in treating patients with fulminant hepatic failure due to exacerbation of chronic hepatitis B. Hepatitis B e antigen seroconversion was less durable in this subgroup of patients and long-term therapy may be required.

Incidence of gastroesophageal malignancy in patients with dyspepsia in Hong Kong: implications for screening strategies

BACKGROUND

A "test-and-treat" strategy for H pylori infection has been recommended in Europe and North America as safe and cost-effective for management of patients with dyspepsia. The primary aim of this study was to determine the frequency of gastroesophageal cancer in 2 groups of patients with dyspepsia: those 45 years of age or younger without "alarm" symptoms (low-risk group) and patients over 45 years of age or any patient with "alarm" symptoms (high-risk group). A secondary aim was to determine the frequency of gastric cancer among patients in the low-risk group with or without a positive serology for H pylori.

METHODS

Patients with persistent dyspepsia were recruited from 4 regional hospitals in Hong Kong. Those in the low-risk group were evaluated for H pylori by using a whole blood serology test; they underwent endoscopy within 1 week. Those in the high-risk group and those taking nonsteroidal anti-inflammatory drugs (NSAIDs) underwent endoscopy promptly. Alarm symptoms were as follows: weight loss (10 or more pounds over 8 weeks), recurrent vomiting, dysphagia, bleeding, or anemia.

RESULTS

Of 2627 patients enrolled, 1017 were in the low-risk group and 1610 in the high-risk group. Twenty-three patients (0.9%) had gastroesophageal cancers (20 gastric, 3 esophageal). Four patients with cancer (17.4%) were in the low-risk group (3 gastric, 1 esophageal); all except the patient with esophageal cancer had a positive serology test. In the high-risk group, 19 patients had cancer (17 gastric, 2 esophageal).

CONCLUSION

Gastric cancer is relatively frequent among young patients with dyspepsia who have no alarm features in Hong Kong. This finding raises concerns as to the safety of the "test-and-treat" strategy for the management of patients with dyspepsia in Asia.

Apoptosis and proliferation in Helicobacter pylori-associated gastric intestinal metaplasia

BACKGROUND

Imbalance between apoptosis and proliferation may be one of the mechanisms underlying H. pylori associated gastric carcinogenesis.

AIM

To examine the cell kinetics of gastric intestinal metaplasia and the effect of H. pylori eradication.

METHODS

Endoscopic gastric biopsies were obtained from 100 H. pylori-infected patients. Apoptosis was determined by triphosphate nick-end labelling (TUNEL) and apoptotic nuclei counting, whereas proliferation was assessed by Ki67 immunostaining. Gastric biopsies were repeated in a sub-group of intestinal metaplasia patients after H. pylori eradication.

RESULTS

Antral apoptotic index was significantly lower in intestinal metaplasia than in non-intestinal metaplasia (0.19% vs. 0.51%; P < 0.0001) whereas the level of proliferation was comparable (28% vs. 22%, P=0.15). Serial antral biopsies taken from 14 intestinal metaplasia patients before and 1 year after H. pylori eradication showed a significant drop in proliferation in both intestinal metaplasia (50% vs. 12%, P < 0.001) and non-intestinal metaplasia area (47% vs. 9%, P < 0.001). A similar fall in apoptosis was detected in non-metaplastic region (0.58% vs. 0.38%, P < 0.001) but not in intestinal metaplasia (0.24% vs. 0.27%, P=0.56), resulting in a significant increase in the apoptosis/proliferation ratio (0.005-0.021; P=0.03).

CONCLUSIONS

Dysregulation in apoptosis control of gastric intestinal metaplasia may contribute to gastric carcinogenesis, which may be retarded by clearance of H. pylori.

Effect of Helicobacter pylori eradication on expression of cyclin D2 and p27 in gastric intestinal metaplasia

BACKGROUND AND AIMS

Cyclins and cyclin-dependent kinase inhibitors play a crucial role in the control of cell cycle transitions. Enhanced expression of cyclin D2 and reduced expression of p27kip1 (p27) have been implicated in the pathogenesis of cancer. Because intestinal metaplasia has been regarded as a pre-malignant lesion, we investigated the expression of cyclin D2 and p27 in Helicobacter pylori-associated chronic gastritis with and without intestinal metaplasia, and followed the changes after H. pylori eradication.

METHODS

Expression of cyclin D2 and p27 was studied by immunohistochemistry in 59 patients (including 35 patients with intestinal metaplasia) and in 10 gastric cancer patients. Among them, 29 H. pylori-infected patients had serial gastric biopsies taken before and at 1-year after eradication of H. pylori.

RESULTS

Expression of cyclin D2 was significantly higher in gastric cancers when compared to their adjacent non-tumour tissues (median score 3 vs. 1, P=0.015). Over-expression of cyclin D2 was detected in H. pylori-associated chronic gastritis and intestinal metaplasia, which was reduced after eradication of the organism (median score 2 vs. 1, P=0.037 in chronic gastritis; median score 2 vs. 0, P=0.008 in intestinal metaplasia). While the normal gastric mucosa showed strong p27 expression, five of the 10 gastric cancer tissues exhibited reduced p27 expression (P=0.039). Diminished p27 expression was also seen in intestinal metaplasia, which was restored 1-year after H. pylori eradication (eight out of 16 vs. one out of 16, P=0.018). Reduced expression of p27 was frequently associated with increased cyclin D2 expression in H. pylori-associated intestinal metaplasia (P=0.02).

CONCLUSION

Over-expression of cyclin D2 and reduced expression of p27 are closely linked to H. pylori-associated intestinal metaplasia. Eradication of H. pylori infection reverses the aberrant expression of cyclin D2 and p27 in intestinal metaplasia.

Inverse association between cyclooxygenase-2 overexpression and microsatellite instability in gastric cancer

This study examined the association between cyclooxygenase-2 (COX-2) overexpression and microsatellite instability (MSI) in gastric cancer. COX-2 expression was assessed by immunohistochemistry and scored in a semi-quantitative manner whereas MSI status was characterized by nine microsatellite markers. The clinicopathological features of cancers including survival data were analyzed. Of the 109 gastric cancers studied, COX-2 overexpression and high level of MSI (MSI-H) was detected in 64.2 and 22.0% cases respectively. Gastric tumors with MSI-H phenotypes had significantly lower level of COX-2 expression levels when compared to MSI-L and MSS tumors (P=0.002). Moreover, COX-2 overexpression was associated with tumor invasion beyond submucosa (P=0.045) and there was a trend favoring better survival in gastric cancers without COX-2 overexpression (P=0.07). The results from this study suggest that gastric cancer with microsatellite instability or COX-2 overexpression present with diverse clinicopathological features.

Concurrent hypermethylation of multiple tumor-related genes in gastric carcinoma and adjacent normal tissues

BACKGROUND

Transcriptional silencing by CpG-island hypermethylation now is believed to be an important mechanism of tumorigenesis. To date, studies on CpG-island hypermethylation in gastric carcinoma and adjacent normal tissues are few.

METHODS

The authors examined 5 gastric carcinoma cell lines, 26 frozen gastric carcinoma tissues and their adjacent nontumor area for concurrent CpG-island hypermethylation in 6 tumor-related genes (p15, p16, E-cadherin, GST-pi, hMLH1, and VHL) by methylation-specific polymerase chain reaction. Nontumorous gastric tissues from 10 gastritis patients were used as controls.

RESULTS

Hypermethylation was not detected in any tissue taken from gastritis patients but was identified in all 5 cell lines and in 24 (92.3%) gastric carcinoma patients. CpG-island methylation in tumor-related genes also was detected in 7 out of the 25 adjacent normal tissues from cancer patients. Hypermethylation of E-cadherin, p15, and p16 were detected more frequently than GST-pi and hMLH1, whereas aberrant methylation of VHL was not detected. Concurrent hypermethylation in 2 or more tumor-related genes was detected in 3 out of the 5 gastric carcinoma cell lines, 22 (84.6%) tumor samples, and 5 (20%) adjacent gastric tissues. Eighteen (69.2%) tumor samples showed hypermethylation in >or= 3 genes.

CONCLUSIONS

The current study showed that concurrent hypermethylation of multiple tumor-related genes is detected frequently in gastric carcinoma and adjacent normal tissues. Study findings suggested that a mechanism that leads to dysregulation in CpG-island methylation is likely to be involved in the early gastric carcinogenesis process.

Concurrent hypermethylation of multiple tumor-related genes in gastric carcinoma and adjacent normal tissues

BACKGROUND

Transcriptional silencing by CpG-island hypermethylation now is believed to be an important mechanism of tumorigenesis. To date, studies on CpG-island hypermethylation in gastric carcinoma and adjacent normal tissues are few.

METHODS

The authors examined 5 gastric carcinoma cell lines, 26 frozen gastric carcinoma tissues and their adjacent nontumor area for concurrent CpG-island hypermethylation in 6 tumor-related genes (p15, p16, E-cadherin, GST-pi, hMLH1, and VHL) by methylation-specific polymerase chain reaction. Nontumorous gastric tissues from 10 gastritis patients were used as controls.

RESULTS

Hypermethylation was not detected in any tissue taken from gastritis patients but was identified in all 5 cell lines and in 24 (92.3%) gastric carcinoma patients. CpG-island methylation in tumor-related genes also was detected in 7 out of the 25 adjacent normal tissues from cancer patients. Hypermethylation of E-cadherin, p15, and p16 were detected more frequently than GST-pi and hMLH1, whereas aberrant methylation of VHL was not detected. Concurrent hypermethylation in 2 or more tumor-related genes was detected in 3 out of the 5 gastric carcinoma cell lines, 22 (84.6%) tumor samples, and 5 (20%) adjacent gastric tissues. Eighteen (69.2%) tumor samples showed hypermethylation in >or= 3 genes.

CONCLUSIONS

The current study showed that concurrent hypermethylation of multiple tumor-related genes is detected frequently in gastric carcinoma and adjacent normal tissues. Study findings suggested that a mechanism that leads to dysregulation in CpG-island methylation is likely to be involved in the early gastric carcinogenesis process.

Concurrent hypermethylation of multiple tumor-related genes in gastric carcinoma and adjacent normal tissues

BACKGROUND

Transcriptional silencing by CpG-island hypermethylation now is believed to be an important mechanism of tumorigenesis. To date, studies on CpG-island hypermethylation in gastric carcinoma and adjacent normal tissues are few.

METHODS

The authors examined 5 gastric carcinoma cell lines, 26 frozen gastric carcinoma tissues and their adjacent nontumor area for concurrent CpG-island hypermethylation in 6 tumor-related genes (p15, p16, E-cadherin, GST-pi, hMLH1, and VHL) by methylation-specific polymerase chain reaction. Nontumorous gastric tissues from 10 gastritis patients were used as controls.

RESULTS

Hypermethylation was not detected in any tissue taken from gastritis patients but was identified in all 5 cell lines and in 24 (92.3%) gastric carcinoma patients. CpG-island methylation in tumor-related genes also was detected in 7 out of the 25 adjacent normal tissues from cancer patients. Hypermethylation of E-cadherin, p15, and p16 were detected more frequently than GST-pi and hMLH1, whereas aberrant methylation of VHL was not detected. Concurrent hypermethylation in 2 or more tumor-related genes was detected in 3 out of the 5 gastric carcinoma cell lines, 22 (84.6%) tumor samples, and 5 (20%) adjacent gastric tissues. Eighteen (69.2%) tumor samples showed hypermethylation in >or= 3 genes.

CONCLUSIONS

The current study showed that concurrent hypermethylation of multiple tumor-related genes is detected frequently in gastric carcinoma and adjacent normal tissues. Study findings suggested that a mechanism that leads to dysregulation in CpG-island methylation is likely to be involved in the early gastric carcinogenesis process.

Economic analysis of four triple regimens for the treatment of Helicobacter pylori-related peptic ulcer disease in in-patient and out-patient settings in Hong Kong

BACKGROUND

One-week triple regimens have been shown to be effective for the treatment of Helicobacter pylori-related peptic ulcer disease.

AIM

To conduct an economic analysis of four triple regimens for the treatment of H. pylori-related peptic ulcer disease from the perspective of a public health organization in Hong Kong.

METHODS

Records of 200 patients with H. pylori-related peptic ulcer disease, who had previously participated in a randomized comparison of ranitidine bismuth citrate (RBC) with amoxicillin and clarithromycin (RAC), omeprazole with amoxicillin and clarithromycin (OAC), RBC with metronidazole and tetracycline (RMT), or, colloidal bismuth subcitrate with metronidazole and tetracycline (BMT) in either in-patient or out-patient setting were reviewed.

RESULTS

Fifty patients were excluded because of incomplete documentation or lack of peptic ulcer. In the out-patient group (n=72), the median direct costs of the RAC group (HK $ 5094) were lower those of the BMT (HK $ 5400), RMT (HK $ 5394), or OAC (HK $ 5440) groups, but the difference was significant only between the RAC and BMT groups (P < 0.05). In the in-patient group (n=78), the median direct costs of the RMT group (HK $ 8524) were significantly lower than those of the OAC (HK $ 13 871) and RAC (HK $ 12 092) groups (P < 0.05), but were similar to those of the BMT group (HK $ 8758).

CONCLUSIONS

RAC and RMT are the least costly regimens for out-patient and in-patient treatment, respectively, of H. pylori-related peptic ulcer disease in Hong Kong.

Biliary tract disease and acute non-A-E hepatitis in Hong Kong: prospective study

OBJECTIVE

To investigate the role of biliary tract disease in patients with acute non-A-E hepatitis.

DESIGN

Prospective study.

SETTING

Infectious diseases unit, government hospital, Hong Kong.

PATIENTS

Sixty-one consecutive patients, admitted with the diagnosis of acute hepatitis and negative hepatitis serology for hepatitis A, B, C, D, and E virus.

MAIN OUTCOME MEASURES

Abdominal ultrasound and endoscopic retrograde cholangiopancreatography findings; clinical outcome.

RESULTS

Ultrasonographic abnormalities indicating biliary tract disease were found in 30% (18/61) of patients. Endoscopic retrograde cholangiopancreatography performed in 78% (14/18) of patients with abnormal ultrasound finding(s) confirmed the presence of biliary tract disease. Age, sex, serum alanine aminotransferase level, and serum albumin level were independent predictors of biliary tract disease in the patients studied.

CONCLUSION

Biliary tract diseases were found in 20% of patients with acute non-A-E hepatitis. Serum amylase and abdominal ultrasonography should be performed for all patients presenting with acute non-A-E hepatitis. Endoscopic retrograde cholangiopancreatography is indicated for those with apparent gallstones or abnormal biliary tract findings.

Role of acid suppressants in prophylaxis of NSAID damage

Gastric acid contributes to the pathogenesis of non-steroidal anti-inflammatory drug (NSAID)-induced ulceration via several mechanisms, including conversion of superficial to deeper injury, impairment of haemostasis, and interference with ulcer healing. The suppression of acid secretion has been shown to reduce the severity of NSAID-induced mucosal damage in experimental models and clinical studies. Current evidence indicates that proton pump inhibitors (PPIs) are the preferred treatment for the healing of gastric ulcers when NSAIDs cannot be discontinued. PPIs are superior to standard-dose H(2)-receptor antagonists and equivalent to low-dose misoprostol in preventing NSAID-induced gastric ulcers. Whether there is any significant advantage of PPIs over higher doses of H(2)-receptor antagonists or misoprostol is unknown. The efficacy of PPIs is enhanced in the presence of H. Pylori infection. Omeprazole has been shown to be effective for the secondary prevention of ulcer bleeding in H. pylori -infected NSAID users. The efficacy of PPIs for the prevention of ulcer complications in H. pylori-negative NSAID users remains uncertain.

Correlation between Helicobacter pylori infection, gastric inflammation and serum homocysteine concentration

BACKGROUND

Epidemiological studies have suggested a link between chronic Helicobacter pylori infection and ischemic heart disease but the underlying mechanism remains elusive. We hypothesized that H. pylori-associated chronic gastritis causes impairment of absorption of vitamin cofactors that are essential in the metabolism of homocysteine and results in hyperhomocysteinemia.

MATERIALS AND METHODS

Forty-nine dyspeptic patients were studied. H. pylori infection was defined by rapid urease test and histology. Fasting serum homocysteine level, which was measured by a validated commercial fluorescence polarization immunoassay, was correlated with H. pylori infection statuses and gastric histology. H. pylori-infected patients were followed up for 24 weeks post eradication for changes in serum homocysteine concentration.

RESULTS

Univariate analyses showed that serum homocysteine level correlated with increasing age (p <.001), male sex (p =.003) and smoking habit (p =.025). There was no significant difference in serum homocysteine levels between H. pylori infected and uninfected subjects (median 10.5 vs. 10.2 micromol/l). After successful eradication of the bacterium, there was no significant reduction in homocysteine level. Moreover, there was no correlation between homocysteine level and gastric histology including H. pylori density, activity and inflammation scores, presence of atrophy or intestinal metaplasia.

CONCLUSIONS

The postulated link between H. pylori infection and ischemic heart disease, if it actually exists, is unlikely to be mediated through hyperhomocysteinemia.

Is non-Helicobacter pylori, non-NSAID peptic ulcer a common cause of upper GI bleeding? A prospective study of 977 patients

BACKGROUND

Non-Helicobacter pylori, non-NSAID ulcer is relatively common in Western countries. Whether it is a significant problem in the Orient is unclear. The aim of this study was to investigate the incidence of non-H pylori, non-NSAID ulcers presenting with GI bleeding.

METHODS

A prospective study was done of 1675 consecutive patients presenting with upper GI bleeding over a period of 12 months. Upper endoscopy was performed with biopsy specimens taken from the antrum and body of the stomach for a biopsy urease test (BUT) and histology for detection of H pylori. Exposure to nonsteroidal anti-inflammatory drugs (NSAID) or aspirin within 4 weeks of hospitalization was carefully scrutinized. A 6-week course of treatment with an H2-receptor antagonist was prescribed for patients who did not use an NSAID and had a negative BUT result. Follow-up endoscopy was performed to confirm H pylori status with a BUT and histology. Positive histology at either initial or follow-up endoscopy was used as the standard for diagnosing H pylori infection.

RESULTS

Among 977 patients who were found to have ulcer bleeding, 434 (44%) had exposure to aspirin or an NSAID. Of the 543 non-NSAID users, 431 (79.4%) had a positive BUT and 112 (20.6%) were BUT negative on initial endoscopy. Eighty-nine of 112 patients who were NSAID negative, BUT negative returned for follow-up endoscopy. Forty-nine of 89 (55.1%) were found to have a positive BUT and positive histology at follow-up endoscopy. Only 40 of 977 (4.1%) patients admitted with ulcer bleeding were confirmed to have non-H pylori, non-NSAID ulcers.

CONCLUSIONS

Non-H pylori, non-NSAID bleeding ulcer is uncommon. A negative BUT is unreliable for exclusion of H pylori infection during the acute phase of ulcer bleeding.

Preventing recurrent upper gastrointestinal bleeding in patients with Helicobacter pylori infection who are taking low-dose aspirin or naproxen

BACKGROUND

Many patients who have had upper gastrointestinal bleeding continue to take low-dose aspirin for cardiovascular prophylaxis or other non-steroidal antiinflammatory drugs (NSAIDs) for musculoskeletal pain. It is uncertain whether infection with Helicobacter pylori is a risk factor for bleeding in such patients.

METHODS

We studied patients with a history of upper gastrointestinal bleeding who were infected with H. pylori and who were taking low-dose aspirin or other NSAIDs. We evaluated whether eradication of the infection or omeprazole treatment was more effective in preventing recurrent bleeding. We recruited patients who presented with upper gastrointestinal bleeding that was confirmed by endoscopy. Their ulcers were healed by daily treatment with 20 mg of omeprazole for eight weeks or longer. Then, those who had been taking aspirin were given 80 mg of aspirin daily, and those who had been taking other NSAIDs were given 500 mg of naproxen twice daily for six months. The patients in each group were then randomly assigned separately to receive 20 mg of omeprazole daily for six months or one week of eradication therapy, consisting of 120 mg of bismuth subcitrate, 500 mg of tetracycline, and 400 mg of metronidazole, all given four times daily, followed by placebo for six months.

RESULTS

We enrolled 400 patients (250 of whom were taking aspirin and 150 of whom were taking other NSAIDs). Among those taking aspirin, the probability of recurrent bleeding during the six-month period was 1.9 percent for patients who received eradication therapy and 0.9 percent for patients who received omeprazole (absolute difference, 1.0 percent; 95 percent confidence interval for the difference, -1.9 to 3.9 percent). Among users of other NSAIDs, the probability of recurrent bleeding was 18.8 percent for patients receiving eradication therapy and 4.4 percent for those treated with omeprazole (absolute difference, 14.4 percent; 95 percent confidence interval for the difference, 4.4 to 24.4 percent; P=0.005).

CONCLUSIONS

Among patients with H. pylori infection and a history of upper gastrointestinal bleeding who are taking low-dose aspirin, the eradication of H. pylori is equivalent to treatment with omeprazole in preventing recurrent bleeding. Omeprazole is superior to the eradication of H. pylori in preventing recurrent bleeding in patients who are taking other NSAIDs.

Validation of a new immunoblot assay for the diagnosis of Helicobacter pylori in the Asian population

BACKGROUND

Performance of commercial serological tests for Helicobacter pylori varies in different populations, largely due to strain heterogeneity and variations in antigenic preparations. Currently available serology tests often show sub-optimal accuracy when used for Asian patients.

AIM

This study evaluated a recombinant antigen-based immunoblot for the diagnosis of H. pylori infection in Chinese patients, and compared it with a conventional ELISA test.

METHODS

Dyspeptic patients referred for diagnostic endoscopy were recruited. The gold standard for H. pylori infection was based on two or more positive results among rapid urease test, histology and (13)C-urea breath test. Serological diagnosis of H. pylori infection was conducted by an ELISA test (pylori DTect; Diagnostic Technology) and an immunoblotting against a novel recombinant antigen (C1S; Genelab), which was constructed by immunological screening of the genomic DNA library of H. pylori.

RESULTS

A total of 87 patients were evaluated and H. pylori infection was diagnosed in 40 (46%) by the reference tests. The sensitivities of the ELISA and immunoblot were 80% (95% CI: 64--91%) and 90% (95% CI: 76--97%), whilst the specificities were 96% (95% CI: 86--96%) and 87% (95% CI: 74--95%), respectively. The respective likelihood ratios of the two tests were 18.6 and 7.0.

CONCLUSIONS

Satisfactory performance is obtained by the use of the new recombinant antigen-based immunoblot for diagnosing H. pylori infection in Chinese patients.

Somatic beta-catenin mutation in gastric carcinoma--an infrequent event that is not specific for microsatellite instability

We screened 90 cases of gastric carcinoma (GCA) samples for beta-catenin exon 3 mutation and assessed its possible relationship with microsatellite instability (MSI). Three mutations were detected in two samples, including a single mutation in an intestinal type and double mutations in a diffuse type GCA. One of the mutations found in the diffuse type GCA sample was a non-sense mutation at codon 68 (CAG-->TAG). This novel mutation was predicted to disrupt the binding of beta-catenin to alpha-catenin and may be related to the diffuse type morphology. The other two mutations were missense mutations involved or related to the GSK-3beta phosphorylation site, which have been reported previously. No MSI can be demonstrated in the two cases with beta-catenin mutation. Our results suggested that beta-catenin mutation was infrequent in GCA and appeared not specific for MSI.

Expression and cellular localization of COX-1 and -2 in Helicobacter pylori gastritis

BACKGROUND

There are conflicting reports on the expression of cyclooxygenase in Helicobacter pylori infection.

AIM

To evaluate the expression of COX-1 and COX-2 in H. pylori gastritis at messenger RNA (mRNA) and protein levels.

METHODS

Endoscopic gastric biopsies were obtained from patients with non-ulcer dyspepsia. The levels of COX-1 and COX-2 mRNA were compared between H. pylori-infected and uninfected specimens using reverse transcription-polymerase chain reaction. The immunohistochemical findings were correlated with the cellular localization of cyclooxygenase mRNA using in situ hybridization.

RESULTS

A total of 40 H. pylori-infected and 40 uninfected specimens were studied. mRNA of COX-2 but not COX-1 was elevated in H. pylori-infected mucosa. COX-1 was localized to the mononuclear inflammatory, endothelial and smooth muscle cells in the lamina propria. COX-2 was barely detectable in uninfected mucosa but was strongly expressed in the foveolar and glandular epithelia in H. pylori gastritis.

CONCLUSION

Cyclooxygenase-1 is expressed in the mononuclear inflammatory, endothelial and smooth muscle cells in the lamina propria irrespective of the H. pylori status. By contrast, H. pylori induces COX-2 expression in the foveolar and glandular epithelia.

Association between cyclo-oxygenase-2 overexpression and missense p53 mutations in gastric cancer

Wild-type p53 competitively binds to the promoter region of COX-2 in vitro and inhibits its transcription. We examined the association between p53 mutation and COX-2 expression in gastric cancer. COX-2 over-expression was seen in 19 (48.7%) cases. These tumours had more lymph-node metastasis (P = 0.048) and tended to have a poorer survival (P = 0.07). Missense mutations of p53 were detected in 20 (51.3%) patients and had a significantly stronger COX-2 expression than tumours without p53 mutation (P = 0.016). Our results suggest a link between p53 mutation and COX-2 overexpression in gastric cancer.

Helicobacter pylori infection in Chinese subjects with type 2 diabetes

The relationship between diabetes and Helicobacter pylori (HP) infection is controversial. In this study, we examined the possible relationship between HP infection and type 2 diabetes in Chinese subjects. Sixty-three Chinese type 2 diabetic patients (mean age +/- SD: 49.9 +/- 12.0 years; range: 17-76 years) were recruited irrespective of the duration of diabetes or type of therapy. Twenty-nine (46%) of them had upper gastrointestinal symptoms and the other 34 (54%) did not. Another 55 age- and sex-matched non-diabetic subjects (mean age +/- SD: 45.6 +/- 15.6 years, p=0.098; range 18-79 years) with dyspepsia indicated for upper endoscopy were recruited as a comparison group. Upper endoscopy was performed with antral mucosal biopsy specimens taken for rapid urease test (CLO test). HP infection was considered to be present if the rapid urease test was positive. The rates of HP infection of the diabetic and non-diabetic individuals were 50.8% and 56.4% respectively (p: NS). The rate of HP infection was similar between the 2 groups of diabetic patients with or without gastrointestinal symptoms (42.9% vs. 56.3%, p: NS). Using logistic regression analysis (forward stepwise) with age, sex, glycaemic control, duration of diabetes and upper gastrointestinal symptoms as independent variables to predict the risk of HP infection in diabetic patients, none of the parameters enter into the model. In conclusion, the rate of HP infection in Hong Kong Chinese subjects with type 2 diabetes is around 50%, which is similar to control subjects. No association was found between HP infection, glycaemic status, and duration of diabetes and upper gastrointestinal symptoms in these diabetic subjects.

Management of nonsteroidal anti-inflammatory drug-related peptic ulcer bleeding

Nonsteroidal anti-inflammatory drugs (NSAIDs) have superseded Helicobacter pylori infection as the most important cause of peptic ulcer bleeding. Eradication of H. pylori in NSAID users will not affect ulcer healing. In high-risk patients with a history of ulcer bleeding, curing H. pylori infection alone without acid suppression has substantially reduced the risk of rebleeding caused by low-dose aspirin but not nonaspirin NSAIDs. In a study comparing the safety profile of misoprostol in combination with NSAID against nabumetone in high-risk patients with a history of ulcer bleeding, both strategies were unable to confer significant protection against the risk of rebleeding.

Up-regulation of cyclooxygenase-1 and -2 in human gastric ulcer

BACKGROUND

The expression of cyclooxygenase (COX) in human gastric ulcers is unknown.

AIM

To study the expression and cellular localization of cyclooxygenase in human gastric ulcers.

METHODS

A total of 38 surgical gastric ulcer specimens were studied; 20 were Helicobacter pylori-positive and 18 were associated with NSAID use. Twenty non-ulcerated, histologically normal gastric specimens were used as controls. The cellular localization of COX-1 and COX-2 were determined by immunohistochemistry and double immunofluorescence. Cyclooxygenase messenger RNA (mRNA) was measured by reverse transcription-polymerase chain reaction and localized by in situ hybridization.

RESULTS

In control specimens, COX-1 was detected in stromal cells in the lamina propria. There was focal and weak immunostaining for COX-2 in the foveolar epithelium. At the ulcer edge, COX-1 was significantly increased in lamina propria cells whereas COX-2 was strongly expressed in the hyperplastic foveolar epithelium in H. pylori- and non-steroidal anti-inflammatory drugs (NSAID)-associated ulcers. At the ulcer base, there was strong expression of COX-1 and COX-2 in myofibroblasts, macrophages and endothelial cells in the granulation tissue, irrespective of H. pylori status or NSAID use. Messenger RNA of COX-1 and COX-2 were demonstrated by reverse transcription-polymerase chain reaction. Double immunofluorescence and in situ hybridization confirmed the cellular localization of cyclooxygenase at protein and mRNA levels, respectively.

CONCLUSION

Both COX-1 and COX-2 are up-regulated in human gastric ulcers.

Randomized trial of low-dose misoprostol and naproxen vs. nabumetone to prevent recurrent upper gastrointestinal haemorrhage in users of non-steroidal anti-inflammatory drugs

BACKGROUND

Prophylactic misoprostol or non-steroidal anti-inflammatory drugs (NSAIDs) with low gastric toxicity (nabumetone) has been shown to reduce mucosal injury.

AIM

To compare nabumetone vs. co-therapy of naproxen with low-dose misoprostol for secondary prevention of upper gastrointestinal bleeding in NSAID users.

METHODS

NSAID users presenting with upper gastrointestinal bleeding were enrolled if they required long-term NSAIDs. After ulcer healing, they were randomized to receive: naproxen (500-1000 mg/day) and misoprostol (200 microg b.d.), or nabumetone (1000-1500 mg/day) and placebo misoprostol for 24 weeks. The primary end-point was recurrent upper gastrointestinal bleeding. The secondary end-point was the proportion of patients suffering from major gastrointestinal events including ulcer bleeding, symptomatic ulcers and severe dyspepsia.

RESULTS

A total of 90 patients were included in the intention-to-treat analysis (misoprostol/naproxen 45, nabumetone 45). Recurrent bleeding occurred in 10 patients (22.2%) receiving misoprostol/naproxen compared with three (6.7%) receiving nabumetone (relative risk 3.33, 95% CI: 0.98-11.32, P=0.069). The proportion of patients suffering from major gastrointestinal events at 24 weeks was 31.1% in the misoprostol/naproxen group and 28.9% in the nabumetone group.

CONCLUSIONS

Misoprostol/naproxen is not superior to nabumetone for secondary prevention of upper gastrointestinal bleeding. Neither low-dose misoprostol nor nabumetone is adequate for high-risk NSAID users.