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M Nunomura

Publications and source records attributed to M Nunomura.

At least 19 recordsLinked to original sources
PubMed2000

A marked stimulation of Fe(3+)-dependent lipid peroxidation in phospholipid liposomes under acidic conditions.

Lipid peroxidation in phosphatidylcholine liposomes induced by Fe(3+) alone, assessed by thiobarbituric acid-reactive substances (TBARS) production, was markedly enhanced as the solution pH was lowered from 7.4 to 5.5. On the other hand, at physiological pH, TBARS production by Fe(3+) was almost negligible. Results of the radical scavenger experiments with superoxide dismutase, catalase and hydroxyl radical ((&z.rad;)OH) scavengers (sodium benzoate, mannitol and dimethylthiourea), deoxyribose degradation and ESR spectrometry suggest that the stimulation of Fe(3+)-dependent lipid peroxidation under acidic conditions is involved in generation of superoxide anion (O(2)(&z.rad;-)), hydrogen peroxide (H(2)O(2)) and (&z.rad;)OH during the reaction. The stimulation of Fe(3+)-dependent TBARS production by increasing the [H(+)] completely disappeared by triphenylphosphine (TPP) treatment of the liposomes, but the reaction was reversible with either incorporation of cumen hydroperoxide (CumOOH) into the TPP-treated liposomes or the addition of CumOOH to the treated liposomes. Incubation of the CumOOH-incorporated TPP-treated liposomes with Fe(3+) at pH 5.5 also resulted in (&z.rad;)OH generation. Based on these results, a possible mechanism of stimulatory effect of Fe(3+) on lipid peroxidation under acidic conditions is discussed.

Antioxidants↗
PubMed1999

Detection of superoxide anion radical in phospholipid liposomal membrane by fluorescence quenching method using 1,3-diphenylisobenzofuran.

Utilization of a fluorescence dye, 1,3-diphenylisobenzofuran (DPBF) as a detector of superoxide anion radical (O2*-) was examined. The fluorescence intensity of DPBF incorporated in phospholipid liposomes consisting of phosphatidylcholine (PC) and phosphatidylserine (PS) is effectively quenched by incubation with xanthine/xanthine oxidase system. On the other hand, xanthine or xanthine oxidase alone did not induce quenching of the DPBF fluorescence in the liposomes. Xanthine/xanthine oxidase-induced fluorescence quenching of DPBF-labeled liposomes was almost completely protected by the addition of superoxide dismutase (SOD, 1 U/ml), but not by heat-denatured SOD (10 min boiling) at the same concentration. On the other hand, catalase (1 U/ml), and hydroxyl radical and singlet oxygen scavengers (10 mM sodium benzoate, 300 mM mannitol, 1 mM tryptophan and 1 mM sodium azide) did not protect xanthine/xanthine oxidase-induced fluorescence quenching of DPBF-labeled liposomes. The concentration dependence profiles of xanthine oxidase on the DPBF fluorescence quenching and O2*- generation showed that there is a good correlation between these parameters. Under the present experimental conditions, approximately 7 microM H(2)O(2)/30 min were produced, but the addition of H(2)O(2) (1 mM) to DPBF-labeled liposomes did not quench the dye fluorescence in the liposomes. Temperature dependence profiles of the DPBF fluorescence quenching induced by xanthine/xanthine oxidase treatment and the excimer fluorescence formation of pyrene molecules embedded in the liposomal membrane suggested that the quenching efficiency of the DPBF fluorescence is largely dependent on their lipid dynamics. Based on these results, we proposed the possibility that DPBF fluorescence quenching method is able to be used as a simple method for detecting O2*- inside the membrane lipid layer and that DPBF fluorescence quenching by O2*- is controlled by the physical state of membrane lipids.

Benzofurans↗
PubMed1999

Nerve-sparing surgery for advanced rectal cancer patients: special reference to Dukes C patients.

Several nerve-sparing operations for advanced rectal cancer that aim to preserve genitourinary function without compromising tumor clearance have been developed in Japan. The aim of this study was to evaluate the survival and local recurrence of these procedures in Dukes B and C patients. A total of 177 patients with advanced rectal cancer underwent curative nerve-sparing surgery (NSS) over the last 11 years; 52 were Dukes B patients and 54 were Dukes C. Altogether 36 had Dukes C1 and 18 had Dukes C2 tumors, 13 with lateral lymph node metastases, designated lateral LN(+). The 5-year survival rate was 92% for Dukes B, 67% for Dukes C1, and 39% for Dukes C2 patients: 11% for Dukes C2 patients with lateral LN(+). The local recurrence rate was 6% for Dukes B, 11% for Dukes C1, and 33% for Dukes C2 patients: 20% for the lateral LN(-) group and 39% for the lateral LN(+) group. Almost all of the patients undergoing NSS could micturate spontaneously, but preservation of sexual function was not as successful. Although there is no guarantee of preserving satisfactory sexual function, our NSS is an acceptable procedure for Dukes B, C1, and C2 patients without lateral lymph node metastases.

Adult↗
PubMed1999

Adult Leigh syndrome with mitochondrial DNA mutation at 8993.

Adult onset Leigh syndrome with a nucleotide (nt) 8993 mutation in mitochondrial (mt) DNA is reported. A 43-year-old woman with a 6-year-history of insulin-resistant diabetes mellitus developed muscular weakness, intractable nausea and vomiting, and anemia. These were followed vertigo, blindness, and deafness with nystagmus. Magnetic resonance imaging (MRI) revealed abnormal high intensities in the bilateral medial regions of the thalamus and periaqueductal gray matters. Autopsy disclosed well-demarcated necrotizing lesions with prominent capillaries in the areas detected by MRI, which were sufficiently diagnostic for Leigh syndrome. MtDNA analysis performed on DNAs extracted from formalin-fixed tissues including liver, heart, brain, muscle, kidney and pancreas showed a T-->G mutation at nt 8993. This is the first case of adult Leigh syndrome demonstrating on mtDNA mutations.

Adult↗
PubMed1998

Surgery for local pelvic recurrence after resection of rectal cancer.

This retrospective study evaluated outcome with regard to procedure, local control, and survival after curative surgical resection with and without preoperative radiotherapy for local pelvic recurrence. A total of 58 consecutive patients with local pelvic recurrence of rectal cancer after previous curative resection for primary tumors were reviewed. Of these, 36 underwent both initial resection and follow-up in our department; the remaining 22 had initial surgery and follow-up elsewhere. Of the 58 patients 27 underwent curative re-resection, 9 had palliative resection, and 22 were treated by conservative therapy. Among the 27 patients with curative resection 17 received preoperative radiotherapy (40 Gy) plus surgery and 10 surgery only. No patients were lost to follow-up; median follow-up time was 36.3 months. The overall rate of curative resection was 46.6%: 55.6% in our own follow-up group and 31.8% in the others. With regard to surgical procedure, abdominoperineal resection (APR) with or without sacral resection was standard following previous low anterior resection, and total pelvic exenteration (TPE) with or without sacral resection was common following APR. There was a high incidence of morbidity (71.4%) after TPE. Re-recurrence was observed in 12 (44.4%) after curative re-resection. There was local re-recurrence in 6 (22.2%). The local re-recurrence rate was 11.8% (n = 2) with radiotherapy plus surgery, and 40.0% (n = 4) with surgery alone. The estimated 5-year survival following curative re-resection was 45.6% (61.2% with radiotherapy plus surgery, 29.6% with surgery alone). Both survival and local control with radiotherapy plus surgery tended to be better than with surgery alone. Thus, in selected patients pelvic local recurrence of rectal cancer can be re-resected curably by APR or TPE (with or without sacral resection) combined with preoperative radiotherapy.

Adult↗
PubMed1998

Clinical evaluation of nerve-sparing surgery combined with preoperative radiotherapy in advanced rectal cancer patients.

BACKGROUND: Since 1984, we have studied nerve-sparing surgery (NSS) combined with preoperative radiotherapy (XRT) in patients with advanced rectal cancer to preserve the genitourinary function without compromising radicality. The present aim was to evaluate the prognosis and the postoperative genitourinary function. METHODS: A total of 167 patients with advanced rectal cancer underwent curative nerve-sparing surgery. Among them, 60 underwent the preoperative therapy using irradiation (42.6 Gy) and tegafur suppository. Survival, local recurrence, and postoperative genitourinary function were investigated in these patients. RESULTS: The 5-year survival rate was 80.9% and the local recurrence rate was 6.7% in the NSS+XRT group. Almost all of the patients receiving NSS could micturate spontaneously, but preservation of sexual function was not as successful. CONCLUSIONS: Better local control and preservation of urinary function were possible in advanced rectal cancer patients by NSS+XRT.

Adult↗
PubMed1996

Ileocolic intussusception in adult due to malignant lymphoma in the cecum with intramural metastasis.

A rare adult case of intussusception caused by malignant lymphoma of the cecum with intramural metastasis is reported. The patient was a 24-year-old man. Ileocolic intussusception was diagnosed by characteristic findings on abdominal computed tomography. Endoscopic examination revealed a massive protuberant tumor, 3 cm in diameter, and a semipedunculated polyp, 1 cm in diameter, in the cecum, which had caused the ileocolic intussusception. Endoscopic biopsy specimens failed to yield a definitive diagnosis histologically, but right hemicolectomy with lymph node dissection was performed. On histologic examination of the surgical specimens, both the tumor and the polyp were diagnosed as diffuse lymphoma of medium-sized cell type, and no lymph node involvement was found. The patient responded well to surgical and chemotherapeutic treatment, and has had no recurrence of malignant lymphoma in the 2 years since the surgical treatment. This was a very rare case of an intussusception in an adult patient due to malignant lymphoma in the cecum with intramural metastasis and without lymph node involvement.

Adult↗
PubMed1996

[Evaluation of endoscopic pirarubicin-Lipiodol emulsion injection therapy for gastric cancer].

To investigate the effect on gastric cancer and metastatic lymph node, an emulsion made of pirarubicin and lipiodol mixture was injected around the lesion of the gastric cancer using gastrointestinal endoscopy. At the site of emulsion injection and lymph node, the concentration of the THP Lipiodol emulsion was enough despite injection more than 7 days before. This targeting therapy for metastatic lymph nodes was considered effective.

Adult↗
PubMed1993

Association of Epstein-Barr virus with gastric carcinoma with lymphoid stroma.

Epstein-Barr virus (EBV) has been detected in lymphoepithelioma of nasopharynx and lymphoepitheliomalike carcinomas in various organs. To clarify the association of EBV with gastric carcinoma with lymphoid stroma, which often resembles lymphoepithelioma, the authors examined 22 such cases by polymerase chain reaction and in situ hybridization techniques. In 18 informative cases, EBV DNA was detected by polymerase chain reaction in 14 (77.8%) cases, including lymph node metastases. EBV RNA was detected within the nuclei of carcinoma cells by in situ hybridization in all cases that were positive by polymerase chain reaction. Infiltrating lymphocytes and normal epithelia adjacent to carcinoma were EBV-negative. Southern blot analysis indicated clonal proliferation of tumor cells and episomal form of EBV. These findings suggest that EBV infection occurs before transformation and may be related to oncogenesis of EBV-associated gastric carcinoma.

Adult↗
PubMed1991

[Post-traumatic syringomyelia. Report of three cases].

Three cases of post-traumatic syringomyelia are presented and the mechanism of syrinx formation is discussed. Two cases were examined radiologically. Computed tomography and magnetic resonance images (MRI) showed an expansive syrinx with adhesive arachnoiditis in the thoracic levels below the injury site and a localized syrinx on the posterolateral gray matter in the cervical levels above the injury site. These syrinxes existed below the C2 level and had no communication with the fourth ventricle. The other was an autopsy case. Postmortem examination revealed that a syrinx existed from C2 to Th6 and had no communication with the fourth ventricle or the central canal. It is concluded that small traumatic cavities in the gray matter evolve to an extensive syrinx by cerebrospinal fluid (CSF) entering via the posterior root entry zone, and adhesive arachnoiditis is an important factor in increasing the CSF which is entering. MRI was useful for the diagnosis.

Adult↗
PubMed1991

[Usefulness of MRI in the diagnosis of spontaneous hematomyelia; a case of intramedullary cavernous hemangioma].

Recent improvement of MRI has enabled us to clearly visualize intramedullary spinal lesions which previously could not be recognized by CT scan or myelography. We reported a case of hematomyelia caused by intramedullary cavernous hemangioma. In this case, MRI was very useful in efforts to recognize the lesions. With the use of MRI, we will be able to accurately ascertain the location and characteristics of intramedullary spinal lesions. The number of surgically treated cases of idiopathic hematomyelia will increase in the future.

Hemangioma, Cavernous↗
PubMed1991

[Magnetic resonance imaging of posttraumatic syringomyelia and its surgical treatment].

Posttraumatic syringomyelia is an uncommon but significant late complication of spinal cord injury. It occurs in approximately 1.1 - 3.2% of cases of spinal injuries. With the increasing availability of CT and magnetic resonance imaging (MRI), the incidence of posttraumatic syringomyelia is increasing. The purpose of this report is to show MRI of posttraumatic syringomyelia and to assess the results of surgical treatment. Materials and Methods This series included 16 cases of posttraumatic syringomyelia studied with MRI. 9 out of 16 cases showed delayed deterioration of neurological symptoms following spinal injuries. The interval between the trauma and the delayed symptoms of deterioration was from 2 years 2 months to 32 years (mean, 8 years and 5 months). There were 13 men and 3 women. The age ranged from 22 to 69 years, with a mean age of 42 years. The initial spinal cord injury was located in the lower cervical region in 4 cases, the thoracic region in 8, and the upper lumbar region in 4. All the patients were studied with resistive 0.15T system (Toshiba MRT 15 A) or a superconductive 0.5T system (Toshiba MRT 50 A) or a superconductive 1.5T system (GE Sigma or Siemens Magnetom). Six patients underwent 8 operative procedures for posttraumatic syringomyelia. Syringoperitoneal shunt was performed in 4 patients, syringosubarachnoid shunt in 3 and ventriculoperitoneal shunt in one. Results 1. MRI In all cases, the posttraumatic syringomyelia was easily diagnosed by MRI. The syrinx extended superiorly and/or inferiorly from the area of the old trauma. In 4 out of 16 cases, the syrinx extended into the medulla oblongata.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Preoperative radiotherapy in rectal carcinoma. 2. The effect of irradiation on lymph node involvement].

A total of 38 cases of advanced rectal cancer (non-radiation group; 25 cases, radiation group; 13 cases) was studied in order to clarify the effect of preoperative radiation therapy (42.6 Gy) on lymph node metastases in rectal carcinoma. In all cases, microcarbon was submucosally injected into the rectal wall the day before operation in order to increase the number of removable lymph nodes from resected specimens as many as possible. By this method, the number of lymph nodes detected per specimen increased from 40 to 60. The incidence of lymph node metastases was 38.5% in radiation group and 64.0% in non-radiation group. The mean number of lymph nodes with metastases was 8.6 in non-radiation group, however, 2.8 in radiation group. With regard to the relationship between size and number of positive lymph nodes, especially in small lymph nodes measuring less than 3 mm, the incidence of metastases was 6.4% in non-radiation group, whereas 0% in radiation group. As a result, it was evident that preoperative radiation therapy in rectal cancer would reduce the number of positive lymph nodes significantly and the effect of radiation was prominent in small lymph nodes.

Charcoal↗
PubMed1991

[Clinicopathological study on rectal cancer after sphincter-saving operation in conjunction with preoperative radiation therapy].

In an attempt to clarify the effect of preoperative radiation on rectal cancer after sphincter-saving resection, radiation group (10 cases) and non-radiation group (22 cases) were studied clinicopathologically. A rate of local recurrence was 36.4% and 10.0% in radiation and non-radiation group, respectively. In cumulative 5-year-survival, non-radiation group showed 70.7%, however, all cases were alive in radiation group. Histological examination demonstrated that such factors predictive of local recurrence as depth of invasion a2, ew (distance between tumor invasion and surgical surface) less than 2 mm, have reduced in radiation group. As a result, it was shown that irradiation had an effect of lowering local recurrences even in cases with high risk factors of local recurrence prescribed above. On the contrary, AW (distance between tumor invasion and anal stump) and frequency of lymph node metastasis had no association with local recurrence, and have not changed favorably even after irradiation. It was also thought to be important to avoid radiation colitis as carefully as possible in radiation therapy for rectal cancer.

Combined Modality Therapy↗
PubMed1990

[A case of cystic metastatic intracranial amelanotic melanoma--analysis of findings in CT and MRI].

A case of cystic intracranial metastatic amelanotic melanoma is presented. As far as we know, cyst formation in intracranial melanoma is rare, and only 15 cases of intracranial amelanotic melanoma have been reported until now. A 63-year-old man was admitted with headache and progressive visual disturbance. CT scan revealed a large low-density mass with ring-like enhancement in the left frontal lobe. Both T 1-and T 2-weighted MRI images revealed hyperintensity. A left frontotemporal craniotomy was performed. A yellowish mass was observed in the frontal lobe. The content of the cyst consisted of old hematoma, xanthochromic fluid and necrotic tissue, was evacuated and the cyst wall was totally resected. No abnormal pigmentation was noted in the cyst wall and surrounding brain tissue. The histological examination revealed amelanotic melanoma. Primary lesion was found on the left thigh later and resected. The patient died of further intracranial metastasis with repeated hemorrhage 5 months after the admission. Both CT and MRI findings of our case is atypical as an intracranial malignant melanoma. However, these are compatible with those of intracerebral hemorrhage in subacute stage. It is suggested that melanoma may make the diagnosis difficult when tumor hemorrhage modifies the images of CT or MRI.

Brain Neoplasms↗
PubMed1990

[Preoperative radiotherapy in rectal carcinoma. I. The effect of irradiation on the tumor volume].

We studied an effect of preoperative radiation upon the change of tumor volume in rectal carcinoma. As a preliminary study, tumor volume of 15 cases of rectal carcinoma with no preoperative irradiation was estimated preoperatively using the transrectal ultrasonography, and were compared with those determined by resected specimens after operation. As a result, there was a parallel relationship between the two values, and mean estimation error rate was 14.6%. Next, the same method was applied to 15 patients with rectal carcinoma who underwent preoperative radiation in order to detect the reduction rate of tumor volume after radiation therapy (42.6 Gy). As a consequence, 80% of cases exhibited the reduction rate more than 50% with an average of 61.7%. It was suggested that the determination of pre- and postoperative tumor volume would be beneficial to evaluation of preoperative radiation therapy as well as decision of the optimal dose of radiation in rectal carcinoma.

Adenocarcinoma↗
PubMed1989

[Clinical evaluation of second-look operations in colorectal cancer].

Second look operations in colorectal cancer after curative resection were undertaken for liver metastasis or local recurrence. In our 247 curative cases, 35 were operated for liver metastasis and 18 for local recurrence. In 35 cases of liver metastasis, 25 had local disease amenable to resection and one had palliative resection. Among 21 pelvic recurrences, 11 had curative re-resection and 2 had palliative resection. The survivors generally experienced relief from various clinical distress, and most of those previously employed could return to work. The actual 3-year survival rate is 51.9% in the group of resected liver metastasis, and 9 of 13 cases resected for local recurrence are alive without evidence of re-recurrence. In conclusion, selected patients with recurrence may recover and resume ordinary living with the second look operation.

Aged↗