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Akihiro Munakata

Publications and source records attributed to Akihiro Munakata.

13 recordsLinked to original sources
PubMed2003

Nucleotide changes in the translated region of SCN5A from Japanese patients with Brugada syndrome and control subjects.

The mutations of the SCN5A gene have been implicated to play a pathogenetic role in Brugada syndrome, which causes ventricular fibrillation. To determine the Brugada-associated mutations in Japanese patients, facilitate pre-symptomatic diagnosis, and allow genotype-phenotype studies, we screened unrelated patients with Brugada syndrome for mutations. DNAs from 6 Japanese patients were obtained and the sequence in the translated region of SCN5A was determined. We could not find the mutations reported previously, but found 17 sites of nucleotide change, consisting of 7 synonymous and 10 non-synonymous nucleotide changes in our patients. Among them, two non-synonymous nucleotide changes (G1663A and G5227A) are specific to our patients and these changes were not found in 53 healthy controls. In 4 patients out of 6, no specific nucleotide change for Brugada syndrome could be detected. Our findings demonstrating no patient-specific change in the translated region of the SCN5A gene among two thirds of the small number of patients examined here imply that another gene other than the SCN5A may be associated with this disease, supporting previous investigations in Japan and other countries.

Adult↗
PubMed2003

Dietary fat attenuates the benefits of an elemental diet in active Crohn's disease: a randomized, controlled trial.

OBJECTIVES: Although an elemental diet has been established as the primary treatment for patients with Crohn's disease, the influence of dietary fat on the elemental diet remains unclear. We have designed the first randomized, controlled trial for elemental diets containing different fat percentages in patients with active Crohn's disease. METHODS: Each patient was randomized to receive one of three dose levels of fat in an elemental diet (Elental) for 4 weeks: 10 patients received low fat (3.06 g/day), 10 patients received medium fat (16.56 g/day) and eight patients received high fat (30.06 g/day). The additional fat was composed of long-chain fatty acids. All patients were evaluated using the International Organization of Inflammatory Bowel Disease rating, plus C-reactive protein level and erythrocyte sedimentation rate, which were measured at weekly intervals. RESULTS: Although the International Organization of Inflammatory Bowel Disease rating, C-reactive protein level and erythrocyte sedimentation rate in the low-fat group decreased, the values in the medium- and high-fat groups fluctuated during the study. The remission rate after 4 weeks in each group was 80%, 40% and 25% for patients in the low-, medium- and high-fat groups, respectively. CONCLUSIONS: When the fat consisted of long-chain triglycerides, a high amount of this fat in the elemental diet formula decreased its therapeutic effect against active Crohn's disease.

Adult↗
PubMed2002

Comparison of etiology of right-sided diverticula in Japan with that of left-sided diverticula in the West.

BACKGROUND AND AIMS: Colonic diverticula are located predominantly on the right-side in patients in Japan, in contrast to those in Europe and the United States. This study compared the etiology of right-sided diverticula in Japan with that of left-sided diverticula in the West. METHODS: A literature review was conducted from 1950 to 2001 using Medline and Index Medicus. RESULTS: Diverticula occur predominantly in the right-sided colon (over 70%) in Japanese patients, and even among Japanese who emigrate, in contrast with the diverticula in Western. Incidence (detection) rates of colon diverticula have rapidly increased in Japan since World War II with the increased dietary fiber intake. The increased detection rate over time is higher in urban areas than in rural areas, and it corresponds to the distribution of dietary fiber intake. Birth cohort analysis suggests that right-sided diverticula is affected more by environmental factors than other types. Furthermore, the significant relationship of right-sided diverticula with intraluminal pressure in Japan is similar to that of left-sided diverticula in the West, and the pathological feature of these diverticula are similar. CONCLUSION: The etiology of right-sided diverticula in Japan (and perhaps also other Mongolian peoples) is very similar to that of left-sided diverticula in the West. The location may represent a difference in morphology of the large intestine between Mongolians (including Japanese), and Westerners, rather than environmental differences.

Age Distribution↗
PubMed2002

Long-term survivors with adult acute leukemia in complete remission: complications and return to work.

For addressing, and eventually being able to predict and prevent, both disease-related complications and changes in social status in long-term acute leukemia survivors, the follow-up is the most important factor after treatment. To this end, we assessed the complications following the attainment of complete remission in adult acute leukemia patients and the changes in social status of patients surviving more than 5 years after disease onset. In our study population of 42 survivors, 24 (57.1%) suffered from various combinations of 18 types of identified complications including posttransfusion hepatitis, diabetes mellitus, and idiopathic osteonecrosis. Regarding fertility, 9 live births were recorded in this cohort, from 2 female patients and the partner of a male patient. Of these 42 long-term survivors, at the time of this report 48.5% were working full- or part-time, 9.0% were unemployed, 30.3% were homemakers, and 12.2% were retired.

Acute Disease↗
PubMed2002

Inhibitory effect of small amounts of cellulose on colonic carcinogenesis with low-dose carcinogen.

This study set out to evaluate the effects of dietary fiber on cancer development in the large bowel under in vivo experimental conditions as similar as possible to those under which this cancer develops in vivo in humans. Forty-eight Sprague-Dawley rats were divided into three groups that were fed either a nonfiber diet or a 3 g or 10 g/100 g cellulose diet in this experiment, and all groups received doses of a mild carcinogen, 1,2-dimethylhydrazine (5 mg/kg body weight) for 50 weeks. Following endoscopic observation of the large bowel, we found that the induction rates of tumor in the cellulose groups were significantly lower than that in the nonfiber diet group, both endoscopically and histologically. No differences were seen between the 3% and 10% cellulose groups in suppressing carcinogenesis. It is likely that the inhibitory effect of 3% cellulose could be confirmed only by a long-term experiment on carcinogenesis following the administration of a low dose of carcinogen.

Animals↗
PubMed2002

Microvessel morphology and vascular endothelial growth factor expression in human colonic carcinoma with or without metastasis.

We quantified microvessel morphology and vascular endothelial growth factor (VEGF) expression in human colonic carcinoma with or without metastasis. The cancerous growth and the noncancerous section of surgical specimens from 36 patients with colorectal carcinoma (14 without metastasis and 22 with metastasis) were studied. Tissue slices immunostained with CD34 were processed for microvessel counts (per mm(2)), the mean diameter of microvessels (microm), and the mean spatial direction of microvessels (degree), defined by the angle between the longitudinal axis of microvessels and the direction perpendicular to the surface of the mucosa. Tissue slices immunostained with anti-VEGF antibody were processed for total epithelial cell counts (per mm(2)), VEGF-positive cell counts (per mm(2)), and VEGF-positive ratio (%). Carcinoma without metastasis had significantly larger microvessel counts (213 +/- 77, p < 0.01), larger microvessel diameter (7.99 +/- 1.77, p < 0.05), and larger spatial direction (47.2 +/- 8.3, p < 0.01) than normal tissue (144 +/- 49 for microvessel counts; 7.03 +/- 0.90 for microvessel diameter; 39.5 +/- 6.6 for spatial direction). Compared with carcinoma without metastasis, carcinoma with metastasis had a significantly larger microvessel diameter (9.75 +/- 2.65, p < 0.03) and lower microvessel counts (180 +/- 92, p = 0.51). Carcinoma without metastasis had a significantly larger VEGF-positive cell count (1276 +/- 805, p < 0.05) and larger VEGF-positive ratio (53.6 +/- 39.3, p < 0.05) than normal tissue (571 +/- 553 for VEGF-positive cell counts; 24.6 +/- 23.2 for VEGF-positive ratio). Carcinoma with metastasis had a significantly lower total cell count (1443 +/- 237, p < 0.001) and lower VEGF-positive cell count (716 +/- 463, p < 0.05) than carcinoma without metastasis. With tumor progression, microvessel diameter significantly increased and microvessel counts decreased, which can be in part explained by VEGF expression. The microvessel diameter seems to be the dominant parameter responsible for cancer cell intravasation as the first step of metastasis.

Adenocarcinoma↗
PubMed2002

New method for the determination of fecal consistency and its optimal value in the general population.

BACKGROUND: Although fecal consistency is an important factor, there has been only one study measuring this parameter. We developed a new method to measure fecal consistency and studied the relationship between fecal consistency and other fecal factors, including water content and weight. METHODS: The new method is a modification of the method of Exton-Smith and used an even balance. Subjects in the initial trial were 26 healthy women. Subsequently, fecal consistency was measured in a representative sample of the general Japanese population, in order to evaluate the optimal value to maintain large bowel function. RESULTS: Correlations between fecal consistency and fecal water content and weight were statistically consistent, although not highly correlated with each other. The optimal mean value was around 300 cm2: 'normal' in 'subjective defecatory state', 295.5 cm2 and 305.2 cm2; 'once/day' in 'defecation frequency', 296.1 cm2 and 310.2 cm2; 'soft and plump' in 'fecal characteristics', 293.6 cm2 and 298.3 cm2, in males and females, respectively. The coefficient of variation of this method ranged from 5.2% to 6.3%. CONCLUSIONS: This method is thought to be applicable to large-scale epidemiological surveys. The optimal value of fecal consistency in the general population was evaluated at approximately 300 g/cm2.

Adult↗
PubMed2002

Cyclooxygenase-2 expression is increased in early intestinal-type gastric cancer and gastric mucosa with intestinal metaplasia.

OBJECTIVE: Cyclooxygenase-2 (COX-2) expression is increased in gastric cancer. We examined COX-2 expression in early stage gastric cancer and background mucosa to elucidate the role of COX-2 in gastric carcinogenesis. METHODS: Thirty-three early gastric cancers obtained from 30 patients infected with Helicobacter pylori were studied. Twenty-three patients had an intestinal, four patients had a diffuse, and three patients had both an intestinal and a diffuse type cancer. Expression of COX-2 protein was detected by immunohistochemistry by counting the number of positive staining cells per 100 cells. RESULTS: Mean COX-2 expression was 84.1 (SD 11.4) in 26 intestinal type cancers and was significantly higher than that in seven diffuse type cancers (23.1 +/- 9.7) (P < 0.001). In three patients who had both the intestinal and the diffuse type cancer, COX-2 expression was 92, 90 and 83 in the intestinal type cancer and only 25, 24 and 7 in the corresponding diffuse type cancer. In 18 patients who had intestinal metaplasia (15 had incomplete metaplasia), COX-2 expression was 60.2 (24.2) in the crypts with metaplasia while it was only 16.8 (10.7) in the crypts without metaplasia (P < 0.001). CONCLUSIONS: COX-2 expression may be associated with the carcinogenesis of the intestinal type gastric cancer and, speculatively, inhibition of COX-2 might have preventative effects on the intestinal type gastric cancer.

Cyclooxygenase 2↗
PubMed2002

Clinical significance of a long common channel.

BACKGROUND/AIM: It was reported that in only 19 (11%) of 173 patients was the common channel at the junction of the pancreatic and bile ducts found to be 6 mm or longer. Pancreaticobiliary maljunction (PBM) is defined as an anomaly with a markedly long common channel with the junction located outside the duodenal wall, so the action of the sphincter of Oddi does not functionally affect the junction. We defined high confluence of pancreaticobiliary ducts (HCPBD) as a length of the common channel > or = 6 mm, in which the communication between the pancreatic and bile ducts was occluded when the sphincter was contracted. This study aims at investigating the clinical significance of HCPBD. METHODS: 2,980 consecutive cases with an adequate endoscopic retrograde cholangiopancreatography were reviewed. PBM and HCPBD were diagnosed according to the above definitions. PBM was divided into two groups: with or without biliary dilatation. RESULTS: PBM and HCPBD were detected in 63 (2.1%) and 50 (1.7%) cases, respectively. Biliary dilatation was detected in 30 cases having PBM. The incidences of gallbladder carcinoma associated with PBM with or without biliary dilatation and HCPBD were 13, 67, and 12%, being significantly higher than in controls (p < 0.05, p < 0.01, and p < 0.05). Pancreatic ductal reflux was detected in 11 (85%) of 13 patients with HCPBD in whom postoperative T tube cholangiograms were performed, and acute pancreatitis occurred in 14 (24%) of the 50 patients with HCPBD. CONCLUSIONS: HCPBD may be an intermediate variant of PBM. It is necessary to pay attention to an associated gallbladder carcinoma in patients with HCPBD as well as in those with PBM.

Adolescent↗
PubMed2000

Does flexible small-diameter colonoscope reduce insertion pain during colonoscopy?

AIM:It is well known that colonoscopy can be difficult due to abdominal pain induced during colonoscope insertion, if sedative agents are not given. Recently, an extra-flexible, small-diameter colonoscope (CF-SV, Olympus Inc.Japan) was developed in order to improve safety and comfort. The aim of this study was to access the usefulness of the CF-SV.METHODS:One hundred patients undergoing sigmoidoscopy were recruited and colonoscopy was performed by one experienced colonoscopist. First, a routine type colonoscope (CF-230I) was inserted into the colon without sedation. When the patient complained of abdominal pain (even if mild), the scope was not advanced further and was withdrawn after the anatomic location of its tip was determined fluoroscopically. Then, the CF-SV was inserted until it reached the cecun or the site where abdominal pain occurred. Previous abdominal surgery and abdominal disease were considered as unfavorable factors (UF) and the relationship between abdominal pain and UF, age and gender were investigated.Furthermore, the colonic insertion pressures in 36 patients with abdominal pain were measured with a force gauge.RESULTS:Thirty-four cases (34%) felt no pain with the CF-230I and successful pancolon-oscopies to the cecum were performed. Sixty-six cases (66%) complained of abdominal pain. The procedure was painless for 47% of men and 24% of women, respectively. The CF-230I scope failed to reach the sigmoid-descending colon junctions in 59 (89.4%) of the 66 patients complaining of abdominal pain. However, CF-SV reached proximal area in 94.9% of those who failed with CF-230I. The median pressure for pain-inducing was 700g/cm(2).CONCLUSION:Unsedated patients with UF were prone to complain of pain when the standard type CF-230I scope was used. The newly developed extra-flexible CF-SV is useful for the aged and for those with UF or being prone to suffer from abdominal pain. Sedative agents may be unnecessary if this new type of colonoscope is used.

Journal Article↗
PubMed2000

Natural History of Colorectal Adenoma and the Effect of Endoscopic Polypectomy on Occurrence of Subsequent Cancer.

Colorectal cancer is thought to originate in colorectal adenoma and endoscopic polypectomy may prove prophylactic. To clarify the natural history of colorectal adenoma and the potential effects of endoscopic polypectomy, we retrospectively studied cohort patients undergoing full colonoscopies at 14 hospitals in Aomori Prefecture between January 1972 and December 1985. Subjects were divided into 3,574 non-adenoma controls and 1,020 adenoma patients, including 530 treated by polypectomy at initial examination. Subjects were followed up until the end of 1987 through record linkage with Aomori Colorectal Cancer Registry files to observe colorectal cancer occurrence. The ratio of observed number/expected number in the general population (O/E ratio) was 0.70 for the adenoma group and 0.36 for controls. The adenoma group was subdivided into polypectomy and non-polypectomy subgroups, with the O/E ratios of 0.39 for polypectomy patients and 0.75 for non-polypectomy patients. The O/E ratio in the adenoma group was about twice in controls, and this ratio in the nonpolypectomy subgroup was also about twice in thepolypectomy subgroup. The results suggest that colorectal adenoma provides a precancerous lesion that can be treated prophylactically by endoscopic polypectomy.

Journal Article↗