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Featured researches published by Toshikazu Murakami.


Journal of the Neurological Sciences | 1979

Morphometric quantification of the cervical limb motor cells in controls and in amyotrophic lateral sclerosis

Hiroshi Tsukagoshi; Nobuo Yanagisawa; Kimio Oguchi; Kazuro Nagashima; Toshikazu Murakami

The limb motor cells of the C6 segment of the spinal cord were counted and correlated with quantified histological findings of biceps brachii muscles in controls and in cases of amyotrophic lateral sclerosis (ALS). In 12 controls the motor cells were divided into larger ones with a minimum diameter greater than 20 micron, and smaller cells. Total numbers of the larger motor cells decreased significantly in 11 of 12 cases of ALS and of the smaller cells in 4 cases. In 4 controls most of the constituents of the biceps brachii muscle were normal-sized fibers, while in ALS smaller fibers and interstitial connective tissue increased and hypertrophic fibers decreased in association with a decrease of normal-sized fibers. The correlation coefficients between total numbers of the larger or smaller motor cells and normal-sized fibers in ALS were 0.92 and 0.65 respectively, and the larger motor cells, correlating with muscular atrophy of the upper arm, were considered to be alpha motor cells. Although in ALS the larger motor cells decreased almost diffusely, there were segmental variations, similar to controls, in numbers of the motor cells per 500 micron thickness.


Human Pathology | 1998

Immunohistochemical study of p21WAF1 and p53 proteins in prostatic cancer and their prognostic significance

Hisashi Matsushima; Takeshi Sasaki; Toshitaka Goto; Yoshio Hosaka; Yukio Homma; Tadaichi Kitamura; Kazuki Kawabe; Atsuhiko Sakamoto; Toshikazu Murakami; Rikuo Machinami

Mutations of p53 tumor suppressor gene occur in a subset of aggressive prostatic carcinomas and are detectable by immunohistochemistry. However, it is uncertain whether p53 overexpression really reflects p53 gene mutation or loss of p53 function. p21WAF1, an inhibitor of cyclin-dependent kinases, is activated by wild-type p53 protein, not by mutant type. Therefore, it is possible that combined analysis of p21WAF1 and p53 proteins aids in determining the functional status of p53 immunostaining. Routinely processed prostatic tissues from 60 patients with prostatic adenocarcinomas were examined by immunohistochemistry for p21WAF1 and p53 expression. As for tissue distribution, p21WAF1 protein was expressed mostly in the luminal layers, in contrast, p53 protein was restricted to the basal layers of benign prostatic glands. In prostatic adenocarcinomas, p21WAF1 protein was more likely to be expressed in well-differentiated areas; in contrast, p53 protein was more likely in poorly differentiated areas in the tumors. The percentage of positive nuclear areas for p21WAF1 and p53 proteins in prostatic adenocarcinomas, assessed by CAS200 computerized image analyzer, were 8.6+/-10% and 16+/-14% (mean+/-SE), respectively. The survival study showed that the p53+/ p21- phenotype showed poorer prognosis than p53+/p21+. Multivariate analysis showed that p21WAF1 expression, clinical stage, and Gleason score were independent prognosticators. In conclusion, p21WAF1 immunohistochemistry is a useful method for interpretation of p53 immunohistochemical results. Combined analysis by p21WAF1 and p53 immunostaining would predict the patient survival more accurately than p53 immunostaining alone.


Diseases of The Colon & Rectum | 1998

Peutz-Jeghers syndrome manifesting complete intussusception of the appendix and associated with a focal cancer of the duodenum and a cystadenocarcinoma of the pancreas : Report of a case

Akemi Yoshikawa; Shu Kuramoto; Toshiki Mimura; Kaoru Kobayashi; Shoji Shimoyama; Hidemitsu Yasuda; Michio Kaminishi; Mitsuru Yamakawa; Takeshi Oohara; Toshikazu Murakami

The unusual occurrence of an “inside-out” appendix reported here is a case of complete intussusception of the appendix of a 45-year-old woman with Peutz-Jeghers syndrome in whom the diagnosis of intussusception was made preoperatively. At laparotomy, the lead point of intussusceptum was revealed to be a Peutz-Jeghers syndrome polyp of the appendix. There was also a cystic lesion in the pancreas, and subsequent distal pancreatectomy revealed a cystadenocarcinoma of the pancreas. Two jejunal Peutz-Jeghers syndrome polyps and two duodenal Peutz-Jeghers syndrome polyps were foundvia intraoperative endoscopies. The duodenal polyps were endoscopically removed, whereas a jejunal wedge resection was performed for the adjoining jejunal polyps. One of the two duodenal polyps possessed an adenocarcinoma focus. To our knowledge, this is the first report of complete intussusception of the appendix caused by a Peutz-Jeghers syndrome polyp.


Journal of Gastroenterology and Hepatology | 2001

A rare case of pseudomyxoma peritonei presenting an unusual inguinal hernia and splenic metastasis

Shouji Shimoyama; Shu Kuramoto; Masaki Kawahara; Kazuki Yamasaki; Hisako Endo; Toshikazu Murakami; Michio Kaminishi

Abstract Pseudomyxoma peritonei (PMP) is a rare clinical entity in which a diffuse collection of intraperitoneal gelatinous fluid is associated with gelatinous implants on the peritoneal surfaces and omentum. Hematogenic or lymphatic metastasis is extremely rare. In addition, an inguinal mass as an initial presentation is also relatively rare. This is a case report of a PMP patient who had splenic metastasis and showed an inguinal tumor as an initial presentation. A 59‐year‐old female patient, who had undergone bilateral oophorectomy because of a ruptured ovarian mucinous tumor of boderline malignancy 12 years previously, presented a presumptive diagnosis of a left inguinal irreducible hernia. Computed tomography revealed a low density mass in the pelvic cavity and in the inguinal lesion, as well as in the spleen without any diseases around the organ. The preoperative serum carcinoembryonic antigen (CEA) level was elevated. The patient underwent a resection of gelatinous tumor in the pelvic cavity, splenectomy, and appendectomy, as well as left inguinal herniorrhaphy. Histological examinations revealed a splenic metastasis of PMP originating from the ovarian low‐grade mucinous tumor. She received postoperative intraperitoneal lavage as well as chemotherapy, and has survived for over 7 years postoperatively without any evidence of recurrence, as confirmed by repeated follow‐up CT examinations and CEA determination. Splenic metastasis of PMP is extremely rare; this represents only the third reported case of its kind in the literature. Furthermore, it should be noted that an inguinal tumor can sometimes be an initial presentation of PMP.


Cancer | 1985

A case of biliary cystadenocarcinoma with recurrent jaundice. Diagnostic evaluation of computed tomography

Hiroshi Kanamori; Hiroki Kawahara; Shoei Oh; Tetsuya Mine; Hitoshi Osawa; Toshikazu Murakami; Etsuro Ogata

A 73‐year‐old male patient with biliary cystadenocarcinoma and episodes of recurrent jaundice is reported. This very rare tumor was suggested as a possible diagnosis by the computed tomographic findings showing intrahepatic cystic masses with septations and papillary projections. The diagnosis of the mucin‐producing tumor was supported by aspiration of mucinous bile with a cannule inserted endoscopically via the major duodenal papilla. The computed tomographic findings and the diagnosis were verified by pathologic studies made on the material obtained surgically. The mucinous bile is assumed to have been responsible for the recurrent jaundice.


Brain & Development | 1990

Studies on pediatric patients with absent auditory brainstem response (ABR) later components

Makiko Kaga; Toshikazu Murakami; Haruko Naitoh; Kenji Nihei

Eleven pediatric patients with only wave I or waves I and II of their ABR were clinically analyzed. The clinical diagnoses of these patients were as follows: 1) anoxic encephalopathy in two cases; 2) neonatal asphyxia in one; 3) infantile Gauchers disease in one; 4) mitochondrial encephalomyopathy in one; 5) suspected Pelizaeus-Merzbacher disease in three; 6) degenerative disease of unknown etiology in two (presumptive diagnosis were progressive supranuclear palsy and dentate-rubro-pallido-Luysian atrophy); and 7) infantile spasms with congenital malformation of the brain and bones in one. The incidence of the patients with this type of ABR abnormality was 0.67% among 1,650 of our pediatric patients whose ABRs were examined because of audiological or neurological problems. All eleven patients showed severe mental retardation. Nine of the eleven had convulsions and likewise, eight of eleven showed deterioration in mental and/or motor activities. Furthermore seven of eleven had disturbed consciousness and four of these seven were in deep coma. Other brainstem and bulbar signs and symptoms were frequently found in these patients. In our series, patients without the later components of ABR manifested marked neurological abnormalities inside and outside the brainstem.


Surgery Today | 1995

Venous hemangioma of the mesoappendix: report of a case and a brief review of the Japanese literature.

Fumika Hanatate; Youichi Mizuno; Toshikazu Murakami

We present herein the rare case of a 48-year-old man in whom an abdominal mass, revealed by celiotomy to be a solid tumor of the mesoappendix, was histologically diagnosed as having a venous hemangioma. To our knowledge, only 18 cases of mesenteric hemangioma have been reported in Japan, including the present case. However, establishing a correct diagnosis preoperatively is extremely difficult despite advanced imaging techniques. In fact, a mesenteric mass was diagnosed preoperatively in only 3 of these 18 cases. Complete excision with or without bowel resection was performed in 16 cases. Interestingly, the histological diagnosis of all the previous cases was cavernous hemangioma, confirming that this report decuments the first case of venous hemangioma of the mesentery in the Japanese literature.


Journal of the Neurological Sciences | 1990

Motor neuron disease: quantitative morphological and microdensitophotometric studies of neurons of anterior horn and ventral root of cervical spinal cord with special reference to the pathogenesis

Toshikazu Murakami

Spinal anterior horn and ventral roots from C6 of spinal cord 6 patients with motor neuron disease (MND) and those from 6 controls were studied morphologically and biochemically, using microscopic observation, morphometry and microdensitophotometry. Spinal anterior horns in MND showed various kinds of morphological changes in nerve cells, and a significant decrease in cellular, nuclear and nucleolar cross-sectional areas in normal and abnormal cells. Microdensitophotometry revealed a significant decrease in the cellular RNA content, of both large cells and small cells, and also of histologically normal appearing cells and abnormal cells. Those findings point to an abnormality of RNA synthesis which precedes the earliest light microscopic changes seen in nerve cells. The cross-sectional areas of myelinated fibers and axons of spinal ventral roots in MND cases showed a significant decrease in the numbers of both total myelinated fibers and large axons. The abnormalities in myelinated fibers and axons of spinal ventral roots in MND cases might be secondary to those in both large nerve cells and small ones of spinal anterior horns in most MND cases and/or primary in some cases.


Pathology International | 1975

Congenital muscular dystrophy associated with micropolygyria(Report of two cases)

Toshikazu Murakami; Yumiko Konishi; Masako Takamiya; Hiroshi Tsukagoshi

This is a report on two autopsy cases of congenital muscular dystrophy assoicated with micropolygyria. The first case was that of an 11‐year‐old boy and the other of a 22‐year‐old male adult. Both cases had similar clinical features, very early onset of disease, diffuse and extensive wasting of skeletal muscles including facial muscles, contracture of joints, hypotonia and mental retardation. In the familial histories of these two cases, the parents of the boy were consanguineous, and a sister of the adult case suffered from muscle weakness and mental retardation. Both of these two cases were clinically diagnosed as congenital cerebromuscular dystrophy (Fukuyamas type). Autopsy revealed marked dystrophy of generalized skeletal muscles and widespread micropolygyria of the brain in both cases. Spinal cords and peripheral nerves were free from any prominent changes. It was concluded that so‐called congenital cerebromuscular dystronphy may be caused by myogenic as well as neurogenic abnormalities during fetal period.


Muscle & Nerve | 1999

Clinicopathological study of an autopsy case with sensory-dominant polyradiculoneuropathy with antiganglioside antibodies.

Tomokazu Obi; Toshikazu Murakami; Masami Takatsu; Susumu Kusunoki; Masahiro Serizawa; Kouichi Mizoguchi; Reiko Koike; Yoshiro Nishimura

A previously reported patient presenting sensory‐dominant neuropathy with antiganglioside antibodies, bound preferentially to polysi‐ alogangliosides including GD1b, was autopsied. While axonal degeneration was predominant in the sural nerve, many demyelinated fibers were present in the spinal roots. Dorsal roots had undergone significant damage. These pathological findings were well correlated with the electrophysiological results showing decreased F‐wave conduction velocities and conduction blocks in motor nerves and decreased or absent sensory action potentials in sensory nerves, with distribution of GD1b in nerve tissues such as dorsal root ganglia and paranodal myelin in the ventral and dorsal roots.

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