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Biomedical subjects

A Munakata

Publications and source records attributed to A Munakata.

At least 37 records · Page 2Linked to original sources

Evaluation of the applicability of the gastric carcinoma risk index for intestinal type cancer in Japanese patients infected with Helicobacter pylori.

The gastric carcinoma risk index is a histological criteria to Helicobacter pylori-infected patients with a high risk of gastric cancer. The aim of this study was to examine the applicability of this index for the intestinal-type gastric cancer in Japanese patients with H. pylori infection. In 55 patients with early intestinal-type gastric cancer and 69 control subjects, we calculated the gastric cancer risk index score by evaluating the grade of mononuclear cell (MNC) and polymorphonuclear cell (PMN) infiltration and the presence of intestinal metaplasia. The gastric cancer index score was significantly higher in patients with gastric cancer (P<0.01). The presence of intestinal metaplasia was significantly more frequent in cancer patients than in controls, while infiltration of MNCs or PMNs in the corpus was not different in the two groups. Within the gastric cancer risk index, the presence of intestinal metaplasia was the only criteria associated with the development of intestinal-type gastric cancer in Japan. The gastric cancer risk index may not be applicable to identify H. pylori-positive patients at high risk of developing intestinal-type gastric cancer in Japan.

Duodenal Neoplasms↗

Acute myeloid leukaemia with trilineage myelodysplasia complicated by masked diabetes insipidus.

We describe a rare case of acute myeloid leukaemia with trilineage myelodysplasia complicated by central diabetes insipidus. In the present case, diabetes insipidus was masked by corticosteroid deficiency due to hypopituitarism and clinical symptoms presented after administering methylprednisolone. Although the remission of leukaemia was not achieved by chemotherapy, excessive urinary output was well-controlled by nasal administration of 1-desamino-8-D-arginine vasopressin (DDAVP) during the course.

Acute Disease↗

Clarithromycin-resistance and point mutations in the 23S rRNA gene in Helicobacter pylori isolates from Japan.

BACKGROUND: Resistance of Helicobacter pylori to clarithromycin is mostly due to the point mutations in the 23S rRNA. In Japan, however, the frequency of these mutations has not been fully investigated. Furthermore, no study has used gastric biopsy specimens to detect these point mutations. METHODS: The frequency of primary clarithromycin-resistant H. pylori was examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Eighty-two strains (42 isolated from patients with gastric cancer and 40 isolated from patients with chronic gastritis) were examined. Two biopsy specimens obtained from patients in whom eradication therapy including clarithromycin had failed were also studied. RESULTS: Either A2143G or A2144G point mutation was detected in 90% of clarithromycin-resistant H. pylori strains. Eight out of 82 strains (9.8%) had either A2143G or A2144G point mutation. Only one out of 42 strains in patients with gastric cancer had A2143G mutation, whereas five strains had A2144G and two had A2143G mutations in 40 strains isolated from control subjects. The proportion was significantly lower in patients with early gastric cancer (P < 0.05). This PCR-RFLP was also applicable for DNA samples extracted from biopsy specimens and infection of clarithromycin-resistant H. pylori was observed. CONCLUSION: The results suggest that the point mutation in the 23S rRNA gene is commonly seen in clarithromycin-resistant H. pylori and it contributes to the treatment failure in Japan. The PCR-RFLP system is a sensitive method by which to diagnose H. pylori infection as well as a simple method for detecting clarithromycin resistance without bacterial culture.

Anti-Bacterial Agents↗

Histological analysis of gastritis and Helicobacter pylori infection in patients with early gastric cancer: a case-control study.

BACKGROUND AND AIMS: Infection with Helicobacter pylori is associated with an increased risk of gastric adenocarcinoma. However, most patients with H. pylori infection will not develop gastric cancer. The aims of the present study were to examine which histological features, including H. pylori infection, would increase the risk of gastric cancer using a case-control study. METHODS: Three gastric biopsy specimens were taken from 72 patients with early gastric cancer and 72 age- and sex-matched control subjects. The grade of gastritis was examined according to the updated Sydney System. The presence of H. pylori infection was determined by serology and histology. Odds ratio (OR) of developing gastric cancer was calculated for H. pylori positivity and histological features using conditional logistic regression. For patients with H. pylori infection, histological features in cancer patients and control subjects were compared. RESULTS: The OR of the presence of mononuclear cell infiltration in the corpus and intestinal metaplasia in the angulus were significantly elevated. The grade of mononuclear cell infiltration in the corpus and antrum was significantly higher in both types of cancer patients than controls. Glandular atrophy and intestinal metaplasia were increased in patients with intestinal-type cancer in the angulus and antrum. Bacterial density in the corpus and polymorphonuclear cell infiltration in the antrum were increased in patients with diffuse-type cancer. CONCLUSIONS: Severe chronic gastritis induced by H. pylori infection seems to be associated with diffuse-type gastric cancer. Glandular atrophy and intestinal metaplasia, which occur in gastric mucosa with chronic inflammation, are significantly associated with intestinal-type cancer.

Adult↗

Simple hemostatic procedure for hemorrhagic duodenal ulcer: two cases of arterial hemorrhage quickly controlled by balloon compression.

We utilized balloon compression in two cases of arterial hemorrhage from duodenal ulcers. The bleeding was quickly controlled in both cases. The advantages of this technique are its simplicity and ease of performance, and the fact that it does not require precise identification of the bleeding point in the duodenal bulb. No serious complications, such as perforation or stenosis, are associated with this technique. During the healing of the ulcer, balloon expansion may result in decreased duodenal bulb deformity. The following points, however, should be clarified in future studies: a) the stability of the duodenal bulb after longer-term balloon compression, and b) the optimum amount of cold water to be injected into the balloon and the optimum compression time.

Adult↗

Simple mucosal biopsy criteria differentiating among Crohn disease, ulcerative colitis, and other forms of colitis: measurement of validity.

BACKGROUND: Recently established mucosal biopsy criteria reliably differentiate idiopathic inflammatory bowel disease (IBD) from other forms of colitis (non-IBD), and Crohn disease involving the colon (CD) from ulcerative colitis (UC) but were inconvenient in practical use because of the need for relatively complicated calculations. Our objectives were to establish simple criteria in which calculation could be done in the user's head and to measure their validity. METHODS: On the basis of the above original criteria, we constructed two sets of criteria in which coefficients and constants were simplified to integral numbers. The first set of criteria consisted of the diagnostic categories 'definite IBD', 'probable IBD', 'unknown', 'probable non-IBD', and 'definite non-IBD'. Similarly, the second set had five categories from 'definite CD' to 'definite UC'. The validity of the criteria was evaluated in 117 patients with CD, 125 with UC, and 484 with non-IBD. RESULTS: In categories of probable IBD and probable non-IBD both sensitivity and specificity exceeded 96.3%. Probable CD and probable UC showed sensitivities of 95.7% and 92.0% and specificities of 93.6% and 98.3%. CONCLUSIONS: Despite simplified coefficients and constants, the validity appeared to be high enough to apply the present criteria to routine work.

Adult↗

Evaluation of the clinical relevance of the iceA1 gene in patients with Helicobacter pylori infection in Japan.

BACKGROUND: A novel Helicobacter pylori gene, iceA, has two allelic variants, and the iceA1 strain is associated with peptic ulcer disease. The aims of this study were to evaluate whether the possession of iceA1 gene is associated with gastric cancer or the severity of gastritis. METHODS: Ninety-seven subjects (46 patients with early gastric cancer and 51 control subjects) infected with H. pylori were studied. DNA was extracted from isolated H. pylori strains, and the presence of the iceA1 gene was examined by polymerase chain reaction. The features of gastritis were graded in accordance with the updated Sydney System, using gastric biopsy specimens. RESULTS: iceA1 was found in 61% of patients with gastric cancer and 53% of control subjects (NS). The grade of gastritis in iceA1-positive and -negative gastric mucosa was compared. Higher polymorphonuclear cell infiltration was observed in iceA1-positive subjects (P < 0.05). However, no significant difference was observed in the grades of mononuclear cell infiltration, glandular atrophy, and H. pylori density. CONCLUSIONS: Our results suggest that the iceA1 gene is not associated with the development of gastric cancer in Japan, whereas the iceA1-positive strain may induce more enhanced active gastric inflammation in cagA-positive and vacA s1/m1 strains.

Alleles↗

Spermatic cord metastases from gastric cancer with elevation of serum hCG-beta: a case report.

Spermatic cord metastases from gastric cancer are rare. We here document a case involving a gastric cancer that mimicked primary testicular tumor because of elevation of the serum human chorionic gonadotropin-beta (hCG-beta). The possibility of metastasis or recurrence of prior malignancies should therefore be considered when the clinical features described here are encountered, although elevation of hCG-beta is rare with tumors other than those in testis.

Biomarkers↗

Serum anti-Lewis X antibody is not elevated in patients with gastric cancer infected with Helicobacter pylori.

Lipopolysaccharides of Helicobacter pylori express Lewis X similar to that occurring in gastric mucosa. Patients infected with H. pylori produce anti-Lewis X antibodies. The aim of this study was to examine whether anti-Lewis X antibody was associated with the development of gastric cancer, particularly intestinal type cancer. Serum sample was collected from 98 patients with early gastric cancer and 98 gender- and age-matched control subjects who underwent endoscopy. Histologically, 77 cancers were of the intestinal type. Titers of anti-H. pylori and anti-Lewis X immunoglobulin G (IgG) antibodies were assayed by enzyme-linked immunosorbent assay. The mean titer of Lewis X antibody was 0.097 in patients with gastric cancer and 0.110 in matched control subjects (not significant). In 72 H. pylori-seropositive patients with intestinal type cancer and their matched H. pylori-seropositive controls, mean titer was 0.115 and 0.107, respectively (not significant). The odds ratio for the risk of gastric cancer if Lewis X antibody was high titer was 0.93 (95% CI 0.43-2.00). The odds ratio for the risk of intestinal type gastric cancer in patients with H. pylori infection if Lewis X antibody was high titer was 1.10 (95(% CI, 0.46-2.62). Anti-Lewis X antibody does not seem to be associated with the development of gastric cancer, even the intestinal type cancer.

Aged↗

Association of gastric epithelial apoptosis with the ability of Helicobacter pylori to induce a neutrophil oxidative burst.

Both polymorphonuclear cell infiltration and increased epithelial apoptosis are seen in gastric mucosa in the presence of Helicobacter pylori infection. This study examined the association between bacterial ability to stimulate an oxidative burst in neutrophils and epithelial apoptosis. Biopsy specimens were obtained from 15 patients to detect apoptotic cells by the TUNEL method. H. pylori strains isolated from corresponding stomach biopsy samples were tested for the ability to stimulate an oxidative burst in human neutrophils. Neutrophils were isolated from healthy subjects without H. pylori infection and the oxidative burst was measured by flow cytometry with dichlorofluorescein diacetate. Stimulation with H. pylori increased both the percentage of activated cells and fluorescence intensity. There was a significant positive correlation between the number of epithelial apoptotic cells and fluorescence intensity. Increased neutrophil oxidative burst stimulated by H. pylori may play a role in enhanced gastric mucosal DNA damage and consequent atrophic gastritis and gastric cancer.

Apoptosis↗

Gastric mucosal inflammation and epithelial cell turnover are associated with gastric cancer in patients with Helicobacter pylori infection.

BACKGROUND: Infection with a virulent Helicobacter pylori strain is associated with gastric mucosal damage and the increased risk of gastric cancer. AIMS: To examine the characteristics of host gastric mucosal responses in patients with gastric cancer, histological grade of gastritis, gastric epithelial apoptosis, and proliferation were studied. METHODS: Thirty two patients with early gastric cancer and 32 sex and age matched controls were studied. All subjects were infected with a virulent H pylori strain (vacA s1/m1, cagA positive genotype). Biopsy specimens were taken from the antrum and the corpus of the stomach. The grade of gastritis was assessed according to the updated Sydney system. Apoptotic cells were detected using terminal uridine deoxynucleotidyl nick end labelling, and epithelial cell proliferation was determined by means of the Ki-67 labelling index. RESULTS: In patients with gastric cancer, significantly higher grades were observed when glandular atrophy (p < 0.05) and intestinal metaplasia (p < 0.01) were present in the antrum, and when mononuclear cell infiltration was present in the corpus (p < 0.05). The numbers of apoptotic cells were increased in patients with cancer (p < 0.05) and the apoptotic index correlated significantly with the grade of glandular atrophy. Epithelial cell proliferation was more likely to be increased in mucosa where intestinal metaplasia was present. CONCLUSIONS: Infection with H pylori causes increased gastric epithelial apoptosis, resulting in more severe glandular atrophy in patients with gastric cancer. Increased damage of gastric epithelial DNA and the presence of more severe atrophic gastritis might contribute to the development of gastric cancer.

Adult↗

Synergistic disaggregation of platelets by the products of endothelial cells or their analogs.

It is known that some products of endothelial cells or their analogs can attenuate the platelet aggregation response and initiate the platelet disaggregation response. Since platelets are involved in the initiation of many clinically important occlusive vascular diseases, we hypothesized that the endothelial cell products act synergistically to disperse platelet aggregates. In this study we examined the synergistic platelet disaggregating effects among the products of endothelial cells. We used urokinase, prostaglandin I2 (PGI2), and sodium nitroprusside (SNP) (which is the chemical substitute as nitric oxide(NO)-donor) for endothelium-derived relaxing factor (EDRF). Platelet disaggregation rate was increased in a dose-dependent manner and decreased in a time-dependent manner, and the combined use of two or three agents had synergistic effects on platelet disaggregation. Furthermore, flow cytometric analysis showed decreases in the binding of fibrinogen to activated platelets by the addition of PGI2 or SNP. These data revealed that these products or their analogs could inactivate the activated platelets or aggregated platelets by detaching fibrinogen from platelets. In addition our data revealed that PGI2 and SNP can act synergistically with fibrinolytic agents. These findings suggest a potential strategy for improving the efficacy of thrombolytic therapy by a combination of these products or their substitutes.

Adenosine Diphosphate↗

Long-term prognosis of patients with ulcerative colitis in Japan.

Even though it is important in improving the quality of life to evaluate the long-term prognosis of patients with ulcerative colitis in comparison with the general population, it is unknown in detail. One hundred and seventeen cases followed-up for 10 years or more were evaluated to define the long-term prognosis of ulcerative colitis by the person-years method. The estimated number of death (E) was 14.5, and the observed number of death (O) was 20. The O/E ratio was 1.38 and confidence interval was 0.84-2.13, showing no significant difference between E and O. Evaluation of change in the O/E ratio at 5-year intervals revealed a decrease in both the males and females, with a significant difference observed between the ratios in 1960 and 1965 (each p < 0.05). Generally, the death rate was significantly higher in the patients with ulcerative clitis than in the general population between 1953 and 1965 but did not significantly differ thereafter. On the other hand, the E from malignant tumors was 3.94, and the O was 4; the O/E ratio was 1.02 and 95% confidence interval was 0.27-2.60, showing no significant difference between E and O.

Adolescent↗

Absence of Mycobacterium paratuberculosis DNA in intestinal tissues from Crohn's disease by nested polymerase chain reaction.

A role of Mycobacterium paratuberculosis in Crohn's disease has been suggested for many years. To determine whether Mycobacterium paratuberculosis has the potential to cause Crohn's disease, we investigated Crohn's disease tissues for the presence of Mycobacterium paratuberculosis, using highly sensitive nested polymerase chain reaction (PCR). DNA was extracted from samples of intestine obtained from 13 patients with Crohn's disease, 14 patients with ulcerative colitis, and 13 control patients without inflammatory bowel disease. Nested PCR was performed using primer pairs complementary to sequences in the insertion element IS900 gene of Mycobacterium paratuberculosis. No Mycobacterium paratuberclulosis-specific PCR product was detected in any of these specimens, although PCR products of the appropriate size were consistently obtained using control DNA template from Mycobacterium paratuberculosis. The results did not suggest that Mycobacterium paratuberculosis is involved in the pathogenesis of Crohn's disease.

Adolescent↗