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Featured researches published by Naoto Maeda.


Journal of Gastroenterology | 1995

Hepatic failure in a case of multiple myeloma-associated amyloidosis (k-AL)

Tetsuo Yamamoto; Naoto Maeda; Hironaka Kawasaki

We report a case of kappa-AL amyloidosis which rapidly developed hepatic failure in a 79-year-old Japanese female who was admitted to our hospital because of abdominal distension and loss of appetite. Laboratory examination revealed a marked deterioration of liver function with cholestasis and monoclonal gammapathy. At the time that the diagnosis of IgG-k type multiple myeloma was made, jaundice was advanced, with continuous gastrointestinal bleeding. The patient died of hepatic failure 2 weeks after admission. Needle biopsy of the liver revealed a diffuse, massive deposition of amyloid protein.


Oncology | 1999

Prognosis for pedunculated hepatocellular carcinoma.

Yutaka Horie; Azusa Shigoku; Hisao Tanaka; Yasushi Tomie; Naoto Maeda; Ushio Hoshino; Masahiko Koda; Goshi Shiota; Tetsuo Yamamoto; Seiichi Kato; Yoshikazu Murawaki; Takeaki Suou; Hironaka Kawasaki

We retrospectively compared the outcome of 13 patients at our institution and that of 163 reported cases of pedunculated hepatocellular carcinoma (HCC) with that of conventional HCC subdivided by tumor diameter (group A: less than 2 cm; group B: 2–5 cm, group C: more than 5 cm). The survival of patients with pedunculated HCC in the 163 reported cases was no different from that of group B, but less favorable than in group A (p < 0.01) and more favorable than in group C (p < 0.01). Among the 163 patients with pedunculated HCC, the 113 cases of surgically treated patients had higher survival than the 21 patients treated with transcatheter arterial embolization (n = 16) or transcatheter arterial infusion chemotherapy (n = 5) (p < 0.01) and than 29 conservatively treated patients (p < 0.001). A total of 70 patients out of 163 (42%) died within 1 year after diagnosis. Additionally, almost all cases of pedunculated HCC showed histologically moderately or poorly differentiated characteristics according to Edmondson and Stainer’s classification or the WHO classification. These results suggest that pedunculated HCC has not a favorable prognosis if appropriate surgical resection has not been performed very early within a few months because of its rapid progressive nature.


Pathology International | 1989

Osteosarcoma with Prominent Epithelioid Features

Haruhiko Yoshida; Tokichi Yumoto; Hironobu Adachi; Takeshi Minamizaki; Naoto Maeda; K. Furuse

Osteosarcoma in the metaphysis to epiphysis of the left femur of a 17 year old male is reported. The lesion appeared osteolytic with sclerotic foci on roentgenographs, accompanied by an extensive tumor shadow in the surrounding soft tissue. While 60% of the tumor was necrotic, histological examination of the remaining viable tissue revealed that it consisted almost entirely of a sheet of epithelioid cells, separated by thin, fibrovascular septa with an alveolar‐like pattern, suggestive of metastatic carcinoma. Only a few areas were characterized by malignant osteoid tissue intermingled with the above cells, showing significant positivity for bone‐specific alkaline phosphatase and 5 nucleotidase, thus permitting a diagnosis of osteosarcoma. Autopsy findings revealed that the metastatic foci were histologically similar to those of the primary tumor. Electron microscopy revealed poor development of cytoplasmic organelles, supporting possible derivation from an osteoblastic cell lineage at an early stage. Acta Pathol Jpn 39: 439 445, 1989.


Journal of Human Genetics | 2000

Two deletion mutations in the hydroxymethylbilane synthase gene in two unrelated Japanese patients with acute intermittent porphyria

Naoto Maeda; Yutaka Horie; Kaori Adachi; Eiji Nanba; Hironaka Kawasaki; Makoto Daimon; Yoshiro Kudo; Masao Kondo

AbstractAcute intermittent porphyria (AIP) is an autosomal dominant inherited disease caused by a decreased activity of hydroxymethylbilane synthase (HMBS). Regarding the abnormalities of the HMBS gene, many different mutations have been reported worldwide; however, few families from Japan have been studied. In this work, we investigated the presence of mutations in two unrelated Japanese patients with AIP. Mutational analysis was performed using the polymerase chain reaction-single strand conformation polymorphism (SSCP) method, followed by DNA sequencing. Reliable restriction enzyme cleavage assays were also established for the pedigree analyses. Unique SSCP patterns were noted in exons 12 and 15 of the HMBS gene. Sequencing revealed different mutations in each patient: a two-base deletion of CT at nucleotide 730–731 (730delCT), and also a two-base deletion of CA at position 982–983 (982delCA). Both of the deletion mutations lead to truncated proteins with an abnormal C-terminus, which would be expected to decrease the stability and/or activity of HMBS. Using the cleavage assays, we were able to definitively identify gene carriers in the family. This study adds a novel mutation to those that have been previously reported, and emphasizes that molecular analysis would be very useful not only for the identification of asymptomatic gene carriers in the family but also for the detection of ancestral founders in porphyria families.


Digestive Endoscopy | 2010

Schistosomiasis japonica identified by laparoscopic and colonoscopic examination.

Keiko Hosho; Yuichiro Ikebuchi; Masaru Ueki; Keiko Nakamura; Kazuo Yashima; Naoto Maeda; Masahiko Koda; Yoshikazu Murawaki; Takeaki Suou; Masayuki Inoue

A 45‐year‐old Philippine woman who came from Mindanao Island was admitted to our hospital with a complaint of epigastric discomfort. Abdominal ultrasonography and computed tomography demonstrated a network pattern and linear calcification in the liver. Laparoscopic examination showed numerous yellowish, small speckles over the liver surface. The liver surface was separated into many small blocks by groove‐like depressions, demonstrating a so‐called tortoise shell pattern. Conventional colonoscopy and narrow‐band imaging showed irregular areas of yellowish mucosa, and diminished vascular network and increased irregular microvessels extending from the descending colon to the rectum. Liver biopsy showed many Schistosoma japonicum eggs in Glissons capsule and colon biopsy showed many S. japonicum eggs in the submucosal layer. These findings established a diagnosis of schistosomiasis japonica. The present case is imported schistosomiasis japonica. Even though new cases have not occurred recently in Japan, we should remain aware of schistosomiasis japonica for patients who came from foreign epidemic areas.


Hepatology Research | 1999

Solitary hepatic tuberculoma with chronic hepatitis C diagnosed by polymerase chain reaction using paraffin-embedded resected specimen

Naoto Maeda; Shinsuke Tanaka; Hironobu Andachi; Mitsuhiko Osaki; Yutaka Horie; Takeaki Suou; Hironaka Kawasaki

Abstract We report a patient with solitary hepatic tuberculoma complicated by hepatitis C, that was definitively diagnosed by polymerase chain reaction (PCR). In a 60-year-old male with chronic hepatitis C, screening ultrasonography demonstrated a liver tumor. Abdominal computed tomography demonstrated a space-occupying lesion showing various fat concentrations in the right anterior superior subsegment of the liver. Magnetic resonance imaging showed a mosaic-like signal intensity of fat in the tumor. Abdominal angiography revealed fine vascular outgrowth and a dark shadow. Under a diagnosis of hepatocellular carcinoma with fatty degeneration, subsegmentectomy was performed. Histopathologically, the tumor included granulation tissues with central necrosis consisting of epitheloid cells and Langhans’ giant cells, suggesting tuberculous granuloma. Although Ziehl–Neelsen staining did not detect acid-fast bacilli, Mycobacterium tuberculosis specific DNA was detected by PCR using paraffin-embedded sections from the resected specimen, leading to a definitive diagnosis of hepatic tuberculoma. Thereafter, the patient received antitubercular therapy, and there has been no relapse to date.


American Journal of Roentgenology | 2003

Diaphragmatic perforation and hernia after hepatic radiofrequency ablation.

Masahiko Koda; Masaru Ueki; Naoto Maeda; Yoshikazu Murawaki


Clinical Biochemistry | 2000

Three novel mutations in the protoporphyrinogen oxidase gene in Japanese patients with variegate porphyria.

Naoto Maeda; Yutaka Horie; Yuichiro Sasaki; Kaori Adachi; Eiji Nanba; Kenji Nishida; Ryuji Saigo; Masanori Nakagawa; Hironaka Kawasaki; Yoshiro Kudo; Masao Kondo


International Journal of Physical Medicine and Rehabilitation | 2013

Relationship between Dysphagia and Serum Substance P Level in Chronic Central Nervous Disease

Yoshiyuki Kishida; Naoto Maeda; Yoshikazu Murawaki


Internal Medicine | 2011

False-Positive Accumulation of Metaiodobenzylguanidine in a Case with Acute Intermittent Porphyria

Tomoko Masuda; Rie Ota; Takao Ando; Naoto Maeda; Yutaka Horie; Toshiro Yoshimura; Masakatsu Motomura; Atsushi Kawakami

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