Gastric intestinal metaplasia as detected by a monoclonal antibody is highly associated with gastric adenocarcinoma

BACKGROUND

Some forms of gastric intestinal metaplasia (GIM) may be precancerous but the cellular phenotype that predisposes to gastric carcinogenesis is not well characterised. Mucin staining, as a means of differentiating GIM, is difficult. A monoclonal antibody, mAb Das-1 (initially called 7E(12)H(12)), whose staining is phenotypically specific to colon epithelium, was used to investigate this issue.

METHODS

Using mAb Das-1, by a sensitive immunoperoxidase assay, we examined histologically confirmed GIM specimens from two countries, the USA and Japan. A total of 150 patients comprised three groups: group A, GIM (fields away from the cancer area) from patients with gastric carcinoma (n=60); group B, GIM with chronic gastritis (without gastric carcinoma) (n=72); and group C, chronic gastritis without GIM (n=18).

RESULTS

Fifty six of 60 (93%) patients with GIM (both goblet and non-goblet metaplastic cells) from group A reacted intensely with mAb Das-1. Cancer areas from the same 56 patients also reacted. In contrast, 25/72 (35%) samples of GIM from patients in group B reacted with mAb Das-1 (group A v B, p<0.0001). None of the samples from group C reacted with the mAb.

CONCLUSIONS

Reactivity of mAb Das-1 is clinically useful to simplify and differentiate the phenotypes of GIM. The colonic phenotype of GIM, as identified by mAb Das-1, is strongly associated with gastric carcinoma.

Prognostic significance of immuno-proteosome subunit expression in patients with renal-cell carcinoma: a preliminary study

Our purpose was to elucidate the clinical roles of the "immuno-proteosome," which is involved in the accelerated pathway of the major histocompatibility complex (MHC) class I-restricted antigen presentation system, in renal cell carcinoma (RCC). The relative expression of six proteosome subunits (existing subunits X, Y, and Z and immunoproteosome subunits LMP7, LMP2, and MECL1) in 54 RCCs was investigated using RT-PCR analysis and was compared with clinicopathological measures, including patient outcome. Expression of the LMP7 and LMP2 genes was significantly low in high-grade tumors, and that of the LMP7 and MECL1 genes was significantly low in high-stage tumors. Low levels of LMP7, LMP2, and MECL1 expression were strongly associated with shortened survival (LMP7: P = 0.0002, LMP2: P < 0.0001, MECL1: P < 0.0047). The levels of subunits X, Y, and Z had no significant correlation with those measures. These findings suggest that RCCs with low level of immuno-proteosome subunit expression have a disorder in their antigen-presentation system. As a consequence, they may escape from immune surveillance and worsen patient outcome.

Evaluation of a telemedicine system for supporting thyroid disease diagnosis

A telemedicine system connecting Japan and Belarus via a communication satellite and the international ISDN has been in use since February, 1999. Two relational databases, which are essentially the same, are set respectively at Nagasaki University School of Medicine and Gomel Regional Specialized Dispensary in Belarus for management of patients' data and for research including epidemiologic studies. The thyroid ultrasonographic images, microscopic images of cytological findings and other information on patients are sent from Gomel to Nagasaki once a week with diagnoses and comments by physicians at Gomel Regional Specialized Dispensary for cases whom they found difficult to diagnose. Thyroid specialists at Nagasaki University School of Medicine correct the diagnoses, if necessary, on the basis of information from Gomel and send their comments and instructions to Gomel for improving diagnosis skills of physicians at Gomel. The findings of 330 cases have been sent from Gomel to Nagasaki by September, 2000 since the commencement of the system in February, 1999. Of the 329 cases, thyroid diagnosis was made at Gomel for 261 cases in whom two or more diagnoses were made for 35 cases. As of the end of October, 2000, the Gomel diagnoses have been reviewed for 217 cases and the remaining 112 cases are under review at Gomel. The diagnoses made at Gomel and Nagasaki were in agreement for 110 (50.7%) of 217 cases. Thyroid cancer was diagnosed in 8 cases in whom 6 had been diagnosed at Gomel while the other 2 were diagnosed anew at Nagasaki. The usefulness of the system for improving thyroid diagnosis in Belarus was indicated.

Oxidized low-density lipoprotein-binding specificity of Asp-hemolysin from Aspergillus fumigatus

Oxidized low-density lipoprotein (Ox-LDL) is known to be involved in the generation and progression of atherosclerosis. Ox-LDL has a number of potentially atherogenic effects on vascular cells, including the uncontrolled uptake by scavenger receptors. We have previously shown that Asp-hemolysin binds to Ox-LDL in a concentration-dependent manner. The present study was undertaken to clarify the binding specificity of Asp-hemolysin to Ox-LDL. We examined the binding specificity of Asp-hemolysin to Ox-LDL using several modified lipoproteins and scavenger receptor ligands. Asp-hemolysin bound to Ox-LDL with shorter LDL oxidation times. However, Asp-hemolysin did not bind to the acetylated LDL. The native high-density lipoprotein (n-HDL) and modified HDL (e.g., acetylated HDL, oxidized HDL) also had no Asp-hemolysin binding. Furthermore, inhibitors of the scavenger receptor binding, including maleylated BSA, polyinosinic acid, dextran sulfate and fucoidin, had no effect on the binding of Ox-LDL to Asp-hemolysin. Surface plasmon resonance studies revealed that Ox-LDL binds with high affinity (K(D)=0.63 microg/ml) to Asp-hemolysin. We concluded that Asp-hemolysin is a specific binding protein with a high affinity for Ox-LDL, and its binding specificity is distinct from any receptor for Ox-LDL. The present studies suggest that Asp-hemolysin may bind to Ox-LDL using a mechanism different from the scavenger receptors.

Immunoglobulin G1 antibody response to Helicobacter pylori heat shock protein 60 is closely associated with low-grade gastric mucosa-associated lymphoid tissue lymphoma

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is related to Helicobacter pylori infection. Specifically, it has been pointed out that pathogenesis of MALT lymphoma involves the 60-kDa heat shock protein (hsp60). To investigate humoral immune responses to the H. pylori hsp60 in patients with gastroduodenal diseases and patients with MALT lymphoma, the hsp60 of H. pylori was expressed with a glutathione S-transferase fusion protein and was purified (recombinant hsp60). Sera were obtained from H. pylori-positive patients with gastroduodenal diseases (MALT lymphoma, n = 13; gastric ulcer, n = 20; duodenal ulcer, n = 20; gastritis, n = 20) and from H. pylori-negative healthy volunteers (n = 9). Sera from patients with MALT lymphoma were also obtained at two times: before and after eradication therapy. Antibodies to hsp60 and H. pylori were assessed by enzyme-linked immunosorbent assay. The levels of immunoglobulin G (IgG) antibodies to the hsp60 of H. pylori-positive patients with gastroduodenal diseases were significantly elevated compared to those in the controls. The levels of IgG1 antibodies to hsp60 were elevated and correlated with the levels of anti-H. pylori antibodies in patients with MALT lymphoma. Humarol immunity against hsp60 may be important and relevant to gastroduodenal diseases induced by H. pylori infection.

Occupational contact urticaria caused by airborne methylhexahydrophthalic anhydride

Acid anhydrides are low-molecular weight chemicals known to cause respiratory irritancy and allergy. Skin allergy has on rare occasions been reported. A total of 3 subjects with occupational exposure to methylhexahydrophthalic anhydride (MHHPA) and hexahydrophthalic anhydride (HHPA) from an epoxy resin system were studied to evaluate the nature of their reported skin and nose complaints (work-related anamnesis, specific IgE, contact urticaria examinations, and ambient monitoring). Using a Pharmacia CAP system with a HHPA human serum albumin conjugate, specific IgE antibody was detected in serum from 1 (33.3%) out of the 3 workers. One unsensitized worker displayed nasal pain and rhinorrhea only when loading liquid epoxy resins into the pouring-machine (2.2 mg MHHPA/m3 and 1.2 mg HHPA/m3), probably being an irritant reaction. Two workers had work-related symptoms at relatively low levels of exposure (geometric mean 32-103 microg MHHPA/m3 and 18-59 microg HHPA/m3); one complained of only rhinitis, and the other was sensitized against HHPA and displayed both rhinitis and contact urticaria (the face and neck). The worker's skin symptoms were evidently due to airborne contact, since she had not had any skin contact with liquid epoxy resin or mixtures of MHHPA and HHPA. These urticaria symptoms were confirmed by a 20-min closed patch test for MHHPA, but not by that for HHPA. The causative agent was considered to be MHHPA, although the specific IgE determination to MHHPA was not performed.

Japanese family with glucocorticoid-remediable aldosteronism diagnosed by long-polymerase chain reaction

We report a Japanese family with glucocorticoid-remediable aldosteronism (GRA) in whom gene abnormality was identified by the long-polymerase chain reaction (PCR) method. The proband was a 21-year-old female incidentally found to have high blood pressure (173/107 mmHg). Laboratory tests showed hypokalemia (3.7 mmol/l), and high plasma aldosterone concentration (PAC, 234 pg/ml) with suppressed plasma renin activity (PRA, <0.1 ng/ml/h). The circadian rhythm pattern and the results of a rapid adrenocorticotrophic hormone (ACTH) test indicated ACTH-dependent changes in PAC. Imaging studies showed no adrenal mass on either side. A dexamethasone (Dexa) suppression test (1.0 mg/day orally for 7 days) showed a marked decrease of PAC 2 days after administration, and this decreased level was maintained throughout Dexa administration. High blood pressure and hypokalemia also improved during Dexa treatment. The proband's younger sister was 19 years old and had hypertension, PAC of 231 pg/ml, and PRA <0.1 ng/ml/h. The mother was 53 years old and had hypertension, PAC of 98.5 pg/ml, and PRA <0.1 ng/ml/h. The proband's elder sister was a 22-year-old normotensive with PAC of 110 pg/ml and PRA of 0.1 ng/ml. Long-PCR was performed for detection of the chimeric gene associated with GRA, using DNA samples from all four cases and two normal control subjects. Although the aldosterone synthase gene was expressed among all DNA samples, the chimeric gene was detected only in the proband, her younger sister and her mother. Our clinical data and genetic investigation confirmed the presence of GRA in this Japanese family.

[Responses to a questionnaire on laboratory examinations performed by graduates of Jichi Medical School in rural practice]

Graduates from Jichi Medical School are obligated to work at rural clinics or hospitals, where most of them are the only medical doctor in the house. Our need to continuously improve medical education, including the learning that takes place in the clinical setting, requires us to understand how these graduates actually use laboratory examinations and what examinations they find most important in their practice. We designed a questionnaire to address these questions. Three hundred sixty-eight graduate physicians working at clinics or hospitals in both rural or urban areas were asked to complete the questionnaire, providing information on the size of their institution, the laboratory equipment and examinations that they have direct access to, and what examinations they find most important. Two hundred seventy-eight (75.5%) of the 368 recipients responded. More than seventy percent of the respondents reported that their institutions had electrocardiographs, abdominal and cardiac ultrasonographs, urinalysis test paper, and portable blood glucose meters; and more than half of them reported having used these instruments without assistance in emergency situations and outside of ordinary office hours. Moreover, a majority of the respondents said that they considered it important that a physician is able to use these instruments without the help of other staff members. These responses clearly show the importance and usefulness of covering examination techniques and the principles of laboratory medicine in medical education.

Alcohol consumption as a major risk factor in the development of early esophageal cancer in patients with head and neck cancer

OBJECTIVE

To clarify the incidence of concomitant esophageal cancers in patients with head and neck cancer (HNC), and to investigate which risk factors are responsible for this association.

PATIENTS AND METHODS

From 1994 to 2000, 134 patients with HNC underwent upper gastrointestinal endoscopy using the 0.8% Lugol stain method to detect esophageal cancer. A case-control study was designed to compare HNC patients with and without esophageal cancer. Logistic-regression analysis was used to obtain odds ratios of risk factors.

RESULTS

Out of 134 patients with HNC, Lugol unstained area was detected in 42 patients. Biopsy specimens revealed squamous cell carcinoma in 17 (12.7%), dysplasia in 9 patients (6.6%), and normal in the others. Gastric carcinoma was also detected in 7 patients (5.2%). The estimated depth of cancer invasion was mucosa in 9 patients, submucosa in 5 patients, and proper muscle or deeper in 3 patients. In the results of statistical analysis, high alcohol consumption of more than 75 g per day increased the risk of esophageal cancer (odds ratio: 20.2, p<0.01). Intake of hard liquor showed a high odds ratio (whisky: 28.7, p<0.05, shochu: 12.7, p<0.05). The amount of cigarette smoking was not related to this association.

CONCLUSION

High incidence of esophageal cancer was found in the patients with HNC. A high alcohol consumption level, and in particular hard liquor, participated in the development of esophageal cancer in the patients with HNC. But cigarette smoking was not related to this association.

Helicobacter pylori induces pepsinogen secretion by rat gastric cells in culture via a cAMP signal pathway

Infection with Helicobater pylori (H. pylori) is associated with various stomach diseases such as chronic gastritis, peptic ulcer, and gastric carcinoma. In order to investigate the mechanisms of enhanced production of pepsinogen by H. pylori in cultured rat gastric cells that have the potential to produce pepsinogen, secretion and synthesis of pepsinogen in the cells exposed to H. pylori extract were determined by measuring the hydrolysis of hemoglobin. Various drugs were used to study the mechanisms of effects of H. pylori on the cells. Exposure of the gastric cells to H. pylori extract caused a significant increase in pepsinogen secretion into the culture medium within 30-180 min in a dose-dependent manner, accompanied by a significant increase in pepsinogen synthesis in the gastric cells after 60 min of incubation. Heat treatment of the H. pylori sonicate at 100 degrees C for 10 min completely abolished the stimulatory effect of H. pylori on pepsinogen secretion. 2',3'-Dideoxyadenosine (50 microM), a specific adenylate cyclase inhibitor, abolished the effect of H. pylori-induced pepsinogen secretion. Puromycin (10 microg/ml), a protein synthesis inhibitor, and nicorandil (0.1 mM), a specific intracellular calcium antagonist, reduced the H. pylori-induced pepsinogen secretion by 37% (p<0.01) and 25% (p<0.05), respectively. On the other hand, actinomycin D (1 microg/ml), an RNA synthesis inhibitor, did not affect the H. pylori-induced pepsinogen secretion. Consequently, dibutyryl cAMP potentially stimulated the pepsinogen secretion from gastric epithelial cells in a dose-dependent manner. H. pylori induces pepsinogen secretion and synthesis by gastric epithelial cells through an increase in the intracellular cAMP and mobilization of the intracellular calcium. In addition, H. pylori affects pepsinogen synthesis at the translational level.

Identification of a human homologue of the dendritic cell-associated C-type lectin-1, dectin-1

Previously we identified the novel type II lectin receptor, dectin-1, that is expressed preferentially by murine antigen presenting dendritic cells (DC) and is involved in co-stimulation of T cells by DC. To identify the human homologue (DECTIN-1), we employed degenerative PCR amplification of mRNA isolated from DC and subsequent cDNA cloning. DECTIN-1 is a type II lectin receptor with high homology to type II lectin receptors expressed by natural killer (NK) cells. It contains an immunoreceptor tyrosine-based activation motif within the cytoplasmic domain. Human DECTIN-1 mRNA is expressed predominantly by peripheral blood leukocytes and preferentially by DC. The mRNA likely encodes a 33 kDa glycoprotein. In human epidermis, the protein is expressed selectively by Langerhans cells, which are an epidermal subset of DC. A truncated form of DECTIN-1 RNA (termed T beta) encodes for a polypeptide lacking almost the entire neck domain, which is required for accessibility of the carbohydrate recognition domain to ligands. Genome analysis showed the deleted amino acid sequence in T beta to be encoded by an exon, indicating that T beta RNA is produced by alternative splicing. DECTIN-1 gene maps to chromosome 12, between p13.2 and p12.3, close to the NK gene complex (12p13.1 to p13.2) which contains genes for NK lectin receptors. Our results indicate that human DECTIN-1 shares many features with mouse dectin-1, including the generation of neck domain-lacking isoforms, which may down-regulate the co-stimulatory function of dectin-1.

The effects of danaparoid, dalteparin and heparin on tissue factor-induced experimental disseminated intravascular coagulation and bleeding time in the rat

Danaparoid and heparin, on the basis of anti-activated factor X (anti-FXa) activity, were equipotent in accelerating the rate of interaction of FXa and antithrombin III. In rat tissue factor-induced disseminated intravascular coagulation (DIC) models, an intravenous administration of danaparoid inhibited the decrease in plasma fibrinogen and platelet counts and the increase in serum fibrinogen degradation products. Expressed on the basis of anti-FXa activity, these effects were comparable with those of dalteparin and heparin. In rat mesenteric small artery and vein, less bleeding was observed after intravenous administration of danaparoid than after dalteparin or heparin. Danaparoid did not affect adenosine diphosphate- or collagen-induced platelet aggregation, and showed weaker inhibitory effects on aggregation induced by thrombin, or collagen + thrombin, than did dalteparin or heparin. These findings suggest that danaparoid may be useful for the prevention of DIC and has less tendency to cause bleeding than dalteparin or heparin, probably as a result of its weaker ability to inhibit platelet aggregation.

A randomized open trial for comparison of proton pump inhibitors, omeprazole versus rabeprazole, in dual therapy for Helicobacter pylori infection in relation to CYP2C19 genetic polymorphism

BACKGROUND AND AIM

The genetic polymorphism of cytochrome P450 (CYP) 2C19 has been shown to influence the efficacy of Helicobacter pylori eradication therapy with a proton pump inhibitor (PPI) and amoxicillin (so-called dual therapy). Omeprazole, a widely used PPI, and rabeprazole, a new PPI, are metabolized in different pathways in terms of CYP2C19 genetic polymorphisms. In this study, we compared the efficacy of omeprazole and rabeprazole in a 2-week dual therapy in relation to CYP2C19 polymorphism.

METHODS

One hundred and ninety-nine patients with peptic ulcer disease were randomly assigned to receive one of the following regimens: 500 mg t.i.d. amoxicillin together with either 20 mg b.i.d. omeprazole or 10 mg b.i.d rabeprazole. The eradication of H. pylori was evaluated by using a bacterial culture and a [(13)C]-urea breath test at 1--2 months after completion of treatment. Cytochrome P4502C19 polymorphism was analyzed by using polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Intention-to-treat-based cure rates for the omeprazole or rabeprazole regimens were 66.3% (95% CI, 56--75) and 62.4% (95% CI, 52--71), respectively, without significant difference. Cytochrome P4502C19 genetic polymorphism did not influence the cure rates in either of these regimens. We analyzed various factors associated with treatment failure (PPI, CYP2C19 genotype, and smoking habit) by using multiple logistic regression; smoking was the only significant independent factor for treatment failure.

CONCLUSION

Omeprazole and rabeprazole were equally effective in combination with amoxicillin in eradicating H. pylori, irrespective of the PPI used (omeprazole or rabeprazole) and CYP2C19 genetic polymorphism. Smoking significantly decreased the cure rate of H. pylori infection in the dual therapy.

Cutting edge: IL-18-transgenic mice: in vivo evidence of a broad role for IL-18 in modulating immune function

IL-18 has been shown to be a strong cofactor for Th1 T cell development. However, we previously demonstrated that when IL-18 was combined with IL-2, there was a synergistic induction of a Th2 cytokine, IL-13, in both T and NK cells. More recently, we and other groups have reported that IL-18 can potentially induce IgE, IgG1, and Th2 cytokine production in murine experimental models. Here, we report on the generation of IL-18-transgenic (Tg) mice in which mature mouse IL-18 cDNA was expressed. CD8+CD44high T cells and macrophages were increased, but B cells were decreased in these mice while serum IgE, IgG1, IL-4, and IFN-gamma levels were significantly increased. Splenic T cells in IL-18 Tg mice produced higher levels of IFN-gamma, IL-4, IL-5, and IL-13 than control wild-type mice. Thus, aberrant expression of IL-18 in vivo results in the increased production of both Th1 and Th2 cytokines.

Chronic treatment with amlodipine modulates adrenocortical angiotensin II receptors in spontaneously hypertensive rats

We investigated the effects of long-term treatment with calcium-antagonist, amlodipine, on angiotensin II receptors in the adrenal cortex of spontaneously hypertensive rats (SHR). Seven-week-old male SHR were treated with oral amlodipine (10 mg/kg/day) or vehicle (saline) for four weeks. Age-matched normotensive Wistar-Kyoto (WKY) rats were treated with the vehicle similar to control SHR. Systolic blood pressure (SBP) showed time-dependent increase in SHR but not in WKY rats, while amlodipine treatment significantly reduced the high SBP in SHR. Plasma renin activity was serially increased in SHR, which was further enhanced by amlodipine treatment. But the plasma aldosterone level which was increased in SHR was not changed by amlodipine. Competitive reverse transcriptase-polymerase chain reaction showed that the level of adrenocortical angiotensin II type 1 receptor (AT1R) mRNA progressively decreased in vehicle-treated SHR compared to WKY rats and that 4-week course of amlodipine treatment significantly increased AT1R mRNA in SHR to levels comparable to those in WKY rats. Amlodipine treatment reduced the level of adrenocortical angiotensin II type 2 receptor (AT2R) mRNA in SHR from 8 weeks of age. Thus, chronic amlodipine treatment differently modulates both adrenocortical AT1R and AT2R in SHR in a possibly direct manner.

[Cytotoxic activity and cytokine gene induction of Asp-hemolysin to vascular endothelial cells]

We examined the effects of Asp-hemolysin from Aspergillus fumigatus Fresenius-Muramatsu strain on the viability and cytokine gene expression of human umbilical vein endothelial cells (HUVEC). The cell viability of HUVEC was reduced to 50% by 100 micrograms/ml of Asp-hemolysin. However, lower concentration of Asp-hemolysin (< 30 micrograms/ml) had no effect on the cell viability. The mRNA expression of such cytokines as tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, IL-6, IL-8 and granulocyte-macrophage colony stimulating factor (GM-CSF) were also observed in HUVEC cultured with 30 micrograms/ml of Asp-hemolysin.