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Dive into the research topics where Akitoshi Murakami is active.

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Featured researches published by Akitoshi Murakami.


Langenbeck's Archives of Surgery | 1989

Definition of carcinoma of the gastric cardia.

Atsunobu Misumi; Akitoshi Murakami; Kazuto Harada; K. Baba; Masanobu Akagi

ZusammenfassungDiese Untersuchung befaßt sich mit der Definition von Carcinomen der Kardia. An 182 Patienten, die weder Hiatushernien, Ulcera noch Neoplasien des Oesophagus bzw. des Magens aufwiesen, wurde die Lage des Übergangs von der Oesophagus- zur Magenmucosa (esophagogastric mucosal junction, EGJ) endoskopisch untersucht. Dann wurde die Beziehung zwischen EGJ und dem Drüsengebiet der Kardia histologisch anhand von 56 Resektaten mit intaktem EGJ und Kardiadrüsenzone untersucht. Außerdem wurde an 102 resezierten Carcinomen mit Sitz in der Nähe des gastrooesophagealen Übergangs die kürzeste Ent fernung zwischen Carcinomzentrum und EGJ und das Ausmaß der Oesophagusinfiltration bestimmt; die Proben schlossen den EGJ ein und konnten pathohistologisch beurteilt werden. Bei der radiologischen und endoskopischen Untersuchung fand sind der EGJ 0,5–1,0 cm vom His-Winkel entfernt. Die histologische Untersuchung zeigte, daß die Kardiadrüsenzone sich vom EGJ etwa 1 cm nach proximal und 2 cm nach distal erstreckt. Die meisten Tumoren des oberen Magens (87,5%), deren Zentrum innerhalb von 2 cm vom EGJ entfernt lag, infiltrierten in den Oesophagus. Ein Kardiacarcinom ist demzufolge als Läsion zu definieren, deren Zentrum innerhalb von 1 cm proximal und 2 cm distal des EGJ liegt.SummaryThis study concerns the definition of carcinoma of the gastric cardia. The topography of the esophagogastric mucosal junction (mucosal EGJ) was investigated with an endoscope in 182 patients who were free of hiatal hernias, ulcers, and neoplasms in the esophagus and stomach. The relationship between the EGJ and the cardiac gland area was then examined histologically in 56 resected specimens containing intact EGJs and cardia gland areas. Furthermore the cancerous center was determined; the shortest distance between the cancerous center and the EGJ and the amount of esophageal invasion were measured in 102 resected carcinomas located close to the junction; the carcinomas contained the EGJ and were good enough for pathohistological examination. The EGJ was located 0.5–1.0 cm proximal to the His angle (the gastric cardia) in radiological and endoscopic examinations. Histologically the cardiac gland area was found to straddle the EGJ at a range of about 1 cm proximal and 2 cm distal to the junction. Among the upper stomach carcinomas, most of the tumors (87.5%) whose center was located within 2 cm from the EGJ invaded the esophagus. In conclusion, carcinoma of the gastric cardia is defined as a lesion with its center located within 1 cm proximal and 2 cm distal to the EGJ.


Annals of Surgery | 1989

Early diagnosis of esophageal cancer: analysis of 11 cases of esophageal mucosal cancer

Atsunobu Misumi; Kazunori Harada; Akitoshi Murakami; Koichi Arima; Hiroyuki Kondo; Masanobu Akagi; Yasushi Yagi; Tsunekazu Ikeda; Yasuhiro Kobori; Hidenobu Matsukane; Kenichiro Baba

We reviewed 11 patients with esophageal mucosal carcinoma in various aspects to improve the early diagnosis of the disease. Eighteen lesions measuring 0.5 to 5.0 cm were confirmed histologically in the 11 cases. Histologically 10 of the 18 lesions were carcinomas in situ (ep cancer), and the other 8 lesions were carcinomas confined to the mucosa other than ep cancer (mm cancer); all 18 lesions were squamous cell carcinomas. Six (85.7%) of the seven mm cancers showed abnormal radiographic findings regardless of the size. Similarly these findings were noted on four of five (80%) ep carcinomas 2 cm or larger in size. All 15 lesions diagnosed before operation showed abnormal findings on conventional endoscopy regardless of the size and depth of transmural invasion. Morphologic change was observed in 9 lesions (53.3%), while 13 (86.7%) showed color change; most of the lesions (80%) were manifested as redness. Dyeing of the resected specimen with Lugol solution (Katayama Chemical Industries, Osaka, Japan) showed all 18 cancerous lesions as unstained areas. Among the 18 lesions, two lesions were unstained areas, which agreed with the areas determined histologically. An additional lesion was visible with dye endoscopy as an unstained area but it was not visible with radiography or conventional endoscopy. Dye endoscopy using Lugol solution is very important because it allows detection and evaluation of the extent of esophageal mucosal cancer.


Journal of Gastroenterology and Hepatology | 1992

Primary hypertrophic pyloric stenosis in the adult

T. Ikenaga; Ubehiko Honmyo; Sadamu Takano; Akitoshi Murakami; Kazunori Harada; Seiichi Mizumoto; Ichiro Yoshinaka; T. Hirata; Masaomi Maeda; H. Kiyohara; Atsunobu Misumi

A case is reported of a 55 year old male patient with primary hypertrophic pyloric stenosis who was subjected to distal gastrectomy. Adult hypertrophic pyloric stenosis is an uncommon condition which is usually misdiagnosed as carcinoma of the antrum. It is a benign disease resulting from hypertrophy of the circular fibres of the pyloric canal and is recognizable radiologically by narrowing and elongation of the pyloric canal and endoscopically by appearances resembling those of the cervix. This condition is probably congenital although aetiology has not been established. In the absence of symptoms, no clinical treatment is required. However, surgical intervention is advocated, when stenosis gives rise to symptoms, there is a suspicion of malignancy, or the ulceration due to the disease. Distal gastrectomy with gastroduodenostomy is the treatment of choice.


Surgery Today | 1989

Postoperative results of distal partial gastrectomy, selective vagotomy plus antrectomy, and selective proximal vagotomy for duodenal ulcers

Atsunobu Misumi; Kazunori Harada; Akitoshi Murakami; Sadamu Takano; Ubehiko Honmyo; Masaomi Maeda; Yasushi Yagi; Masanobu Akagi

We investigated the postperative results of distal partial gastrectomy, selective vagotomy plus antrectomy, and selective proximal vagotomy, to evaluate their effectiveness in the treatment of duodenal ulcers. The operative mortality of selective vagotomy plus antrectomy and selective proximal vagotomy seemed to be lower when compared to distal partial gastrectomy, although each procedure showed a sufficiently low mortality. The acid reduction rate was significantly lower after selective proximal vagotomy than after the other procedures (p<0.01). However, the rate of ulcer recurrence following selective proximal vagotomy tended to be higher compared with the other procedures. All three procedures showed good results according to Visick’s grading and postoperative symptoms occurred in about 50 per cent of all patients, no matter what the procedure. The regaining of physical ability was significantly greater following selective proximal vagotomy than following distal partial gastrectomy (p<0.05) and the capacity to work was also better after vagotomy, particularly selective vagotomy plus antrectomy (p<0.05). Thus, although distal partial gastrectomy and selective vagotomy plus antrectomy proved superior regarding the low ulcer recurrence rate and acid reduction, while selective proximal vagotomy proved superior for improving the quality of life, on the whole the three operations promise almost equivalent results.


Gastroenterologia Japonica | 1981

Solitary ulcer of the rectum: report of a case and review of the literature

Atsunobu Misumi; Yoshihisa Sera; Masakazu Matsuda; Yohei Inamori; Hidechika Kawano; Sadamu Takano; Akitoshi Murakami; Masanobu Akagi

SummaryA 13-year-old girl with Prader-Willi syndrome was admitted to our hospital with an 18-month history of anal bleeding and mucus discharge on defecation.Physical examination revealed obesity, hypogonadism, hypotonia and hypomentia. On digital examination, a nodular mass was palpated on the right wall of the amupulla recti, which was suspected to be carcinoma on a barium enema study. Proctoscopic examination revealed a large, irregular ulceration with white slough at the base, surrounded by the nodular and lumpy mucosa.The lesion was excised by the abdomino-anal pull-through method. The resected specimen showed a lesion of large, shallow, irregular ulcer, 5.0 x 2.2 cm in size. Microscopic examination revealed obliterated lamina propria by fibroblasts and muscle fibers derived from the muscularis mucosae, and misplaced cystic dilated glands in the submucosa at the margin of the ulcer. The gross and microscopic appearances are identical to those of “solitary ulcer of the rectum” described by Madigan and others, and similar to those of “colitis cystica profunda” described by Goodall and others. According to these findings, this lesion was diagnosed as solitary ulcer of the rectum.In the present report, the relationship between solitary ulcer of the rectum and colitis cystica profunda was discussed.


Digestive Endoscopy | 2001

Blood flow, acidity and atrophic changes of the gastric mucosa in Mongolian gerbils infected with Helicobacter pylori

Sebastião Mitsuji Miyazaki; Mimian Graciela Matsuda; Atsunobu Misumi; Ubehiko Honmyo; Akitoshi Murakami; Hiroshi Murata; Katsuro Sagara; Ryouichi Kurano; Hiroaki Okabe

We used a Mongolian gerbil model to evaluate the effects of long‐term Helicobacter pylori infection on blood flow, gastric acidity and atrophic change of the gastric mucosa.


Gastroenterologia Japonica | 1987

The histogenesis of dmhinduced colonic carcinoma in rats

Youhei Inamori; Atsunobu Misumi; Akitoshi Murakami; Masanobu Akagi

SummaryTwenty-one Donryu male rats of six weeks old were injected with 1,2-dimethyl-hydrazine hydrochloride (DMH), once a week, for 4 to 20 weeks, and sacrificed at intervals of two weeks since a lapse of four weeks after the commencement of the injections. The DMH induced 320 atypia lesions, from 0.03 through 20 mm in size, of grade II or higher. The rate of benign lesions was higher in the group receiving less than 20 injections than in the group of 20 injections of DMH, while in the latter group, the rates of the benign, borderline and malignant lesions were stable, suggesting that benign lesions mainly develop in the earlier period of the DMH treatment, and thereafter various grades of lesions develop at a constant rate. All the benign lesions were less than 1 mm in size, and all lesions greater than 1 mm were malignant. In addition, the size of the lesion was significantly greater when it was occupied by malignant crypts in a greater rate. These results indicate that the benign lesions become cancerous before they reach a certain size (adenoma-carcinoma sequence). Twenty-seven minute lesions (less than 1 mm) were mixed lesions of malignant and benign atypia, suggesting that the adenoma-carcinoma sequence is elicited in any size of lesion. On the other hand, there were 41 minute malignant-only lesions, which constituted 27.7% of the overall minute lesions and included three “single crypt” cancers. In addition, malignantonly lesions were smaller when compared to the malignant-dominant mixed lesions. These results indicate that about 30% of colon cancers develop de-novo.


Digestive Endoscopy | 1989

Endoscopic Diagnosis of Early Malignant Lymphoma of the Stomach

Atsunobu Misumi; Ichiro Yoshinaka; Kazunori Harada; Akitoshi Murakami; Hirofumi Kako; Ubehiko Honmyo; Shigeki Ohshima; Makio Sugiyama; Hironobu Suko; Shuji Suko

Abstract: The findings and results obtained by endoscopies and direct vision biopsies carried out in 13 patients with early primary gastric lymphoma, were compared with those of 8 patients with RLH, 28 with depressed type of early gastric carcinoma, and 10 patients with benign gastric ulcers, to deal with problems inherent to endoscopic diagnosis of early primary gastric lymphoma


Gastroenterologia Japonica | 1984

Role of antral mucosa in intestinal phase of gastric secretion in dogs

Yasushi Yagi; Atsunobu Misumi; Akitoshi Murakami

SummaryThis study was performed to investigate the mechanisms and significance of the intestinal phase of gastric secretion.With infusion of 10% liver extract into the duodenum of dogs, serum gastrin levels of the right gastroepiploic vein increased significantly (p<0.01). With infusion of the pH 7.0 liver extract, acid and pepsin outputs in non-antrectomized dogs increased significantly (p<0.01), as did serum gastrin levels (p<0.01). Post-infusion acid output in these dogs was 48±16% of tetragastrin-stimulated output. With the same infusion, antrectomized dogs showed no significant increase of acid and pepsin outputs and serum gastrin levels. Acid output and serum gastrin levels in non-antrectomized dogs that were infused with pH 2.0 liver extract did not increase significantly. The values of almost all serum amino acids in both types of dogs increased slightly, but insignificantly, with pH 7.0 liver extract.We obtained the following conclusions. The intestinal phase of gastric secretion operates by the mediation of the antral mucosa, from which gastrin is released. Although this phase has some effect, the acid-secretory ability of this phase is masked by inhibitory systems under certain physical conditions.


Digestive Endoscopy | 2001

Reversible protruded lesion regarded as idiopathic appendiceal intussusception

Ubehiko Honmyo; Shinya Shimada; Shin‐ichi Yamamoto; Shigeki Oshima; Masaomi Maeda; Ichiro Yoshinaka; Seiichi Mizumoto; Akitoshi Murakami; Atsunobu Misumi

A patient with a reversible protruded lesion regarded as idiopathic appendiceal intussusception was investigated in this study. The patient was a 78‐year‐old male, who consulted our department as a result of positive occult blood in his stool sample. There was no associated pain, nausea, vomiting, fever, chill or anorexia. He had no prior surgical history. Total colonoscopy detected a sigmoidal polyp and a protruded lesion in the caecum. The protruded lesion (about 12 mm in diameter) covered with normal mucosa was diagnosed as a benign submucosal tumor at that time. The periodic follow‐up colonoscopy showed an orifice on top of the protuberance. Further detailed observation revealed that the lesion reduced by itself, and resulted in showing a normal orifice of the appendix; however, afterwards it protruded again. These observations led to the diagnosis of the lesion as type B of Atkinsons classification in appendiceal intussusception. To our knowledge, approximately 200 cases of appendiceal intussusception have been documented in scientific reports worldwide. In Japan, only 10 cases of idiopathic appendiceal intussusception have been described. This case is considered to be important for presenting the initial stage of the complete intussusception of the appendix.

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