Search PubMed⌕ Search

Biomedical subjects

N Nemoto

Publications and source records attributed to N Nemoto.

At least 163 records · Page 9Linked to original sources

Immunohistochemical distribution of laminin-5 gamma2 chain and its developmental change in human embryonic and foetal tissues.

Immunohistochemical distribution of laminin gamma2 chain, a subunit of the basement membrane protein laminin-5, was examined in 19 cases of human embryos and foetuses ranging from 4 to 25 weeks of gestation. Laminin gamma2 was first detected in the basement membranes underlying ectodermal epithelial tissues, such as the skin and tooth, as early as 5-6 weeks of gestation. Between 6-7 and 12-13 weeks, laminin gamma2 was detected in the basement membranes of various endodermal epithelial tissues, such as the bronchus, oesophagus, stomach, intestines, urinary bladder, gallbladder and hepatopancreatic duct. The deposition of laminin gamma2 in basement membrane was associated with the process of morphogenesis. In the small intestine, laminin gamma2 first appeared in the basement membrane of the primitive short villi, and its level gradually increased in the villus region but decreased in the cryptic region during the maturation of the organ. In addition, non-basement membrane immunoreactivity for laminin gamma2 was detected in some mesoderm-derived tissues, such as the cartilage and skeletal and smooth muscle fibres. These results suggest a common role of laminin-5 and some specific roles of its gamma2 chain in the morphogenesis of human tissues.

Basement Membrane↗

Huge IgD plasmacytoma in the abdomen presenting coagulation necrosis.

A 65-year-old Japanese woman was diagnosed in 1996 with a pathological fracture of the left femur caused by immunoglobulin D-type myeloma (IgD myeloma). She responded well to combination chemotherapy followed by irradiation. The patient experienced renal failure and became dependent on haemodialysis. In 1999, large plasmacytomas developed in the abdomen and left humerus. The abdominal tumour appeared to induce gastroduodenal ulcers and jejunal obstruction. We initiated irradiation therapy without chemotherapy to prevent further growth of the plasmacytoma, although treatment-resistant gastroduodenal ulcers developed. Continued blood loss from the gastroduodenal ulcers resulted in a deterioration in the patient's health, which prevented successful haemodialysis. An autopsy showed that the plasmacytoma had undergone coagulation necrosis. We conclude that the use of combination chemotherapy with topical irradiation was an acceptable treatment measure against IgD plasmacytoma; irradiation without chemotherapy was the most likely cause of the coagulation necrosis seen in the plasmacytoma at autopsy.

Abdominal Neoplasms↗

p53 mutation found to be a significant prognostic indicator in distal colorectal cancer.

There has been few reports describing that the prognostic significance of p53 alteration in colorectal tumors depended on the site of origin. Therefore, in this study, we examined whether there is a valid association between the p53 alterations and the prognosis of colorectal cancer patients, especially distal colorectal cancer cases. Tumor samples were collected from 110 patients resected for colorectal cancer between 1989 and 1997. The entire coding region of the p53 gene was analyzed by automated direct sequencing. In addition, the DO-7 monoclonal antibody was used in the immunohistochemical (IHC) assessments. By the Cox univariate analyses in all tumors, Dukes' stage, lymph node metastasis, liver metastasis, p53 mutation and p53 protein overexpression were significant predictors of survival. The cases without p53 mutation showed significantly improved prognosis compared to the cases with p53 mutation (p = 0.0085). In distal tumors, Dukes' stage, liver metastasis, p53 mutation and p53 protein overexpression were significant predictors of survival. Multivariate analysis of all tumors, p53 mutation and liver metastasis were independent indicators of poor survival (p = 0.0223 for p53 mutation, p = 0.0254 for liver metastasis). Also in distal tumors, p53 mutation was an independent indicator (p = 0.0011). Furthermore, the relative risk associated with p53 mutation in distal tumors was much higher than that in all tumors (8.260 vs. 1.796). However, p53 protein overexpression was not an independent indicator of survival in all tumors as well as distal tumors (p = 0.1918 in all tumors, p = 0.0607 in distal tumors). In proximal tumors, p53 mutation was not an independent indicator (p = 0.6673). We think that p53 mutation is a very useful prognostic indicator when distal colorectal cancers are considered.

Aged↗

Relationship between fatty liver and liver metastasis in rats given injection of rat colon cancer cell line.

BACKGROUND/AIMS: In a previous study we described that colorectal cancer patients with fatty liver had few liver metastases. To clarify whether this clinical finding is correct, we studied whether rats with fatty liver had infrequent liver metastases using experimental colon cancer. METHODOLOGY: Twenty male inbred F344/DuCrj rats (CLEA JAPAN Inc.), 8 weeks of age, were used in this study. These 20 rats were divided into two groups: Fatty liver group (FL group, n = 10) and Non-fatty liver group (NFL group, n = 10). 1.0 ml of tumor-cell suspension containing 1 x 10(7) RCN-9 cells was injected just under the capsule of the spleen. All animals were sacrificed 2 weeks after tumor inoculation. RESULTS: 1) Four rats out of 10 in the FL group (40%) had at least one metastatic nodule on the surface of the liver, while there were 10 rats with metastatic nodules in the NFL group (100%) (p < 0.01). 2) The ratio of the liver metastasis area against the largest section of the left lobe of the lateral segment (RLML) was examined. The average RLML of the FL group was 0.45%, which was significantly lower than that of the NFL group (7.11%) (p < 0.0001). CONCLUSIONS: Rats with fatty liver seldom had liver metastases compared to normal rats. This means that fatty liver itself can possibly bring about situations with infrequent liver metastases.

Animals↗

A case of carcinoma associated with the remained intrapancreatic biliary tract 17 years after the primary excision of a choledochal cyst.

Although the incidence of biliary carcinoma associated with choledochal cyst is high, there are extremely rare reports about cancer development in the remaining intrapancreatic biliary tract in patients who underwent primary excision of the choledochal cyst. The authors present a case of carcinoma associated with the remnant intrapancreatic biliary tract in a 39 year-old woman, 17 years after the initial excision of a choledochal cyst with Roux-en-Y hepaticojejunostomy. Long-term follow-up may be recommended even in patients who have undergone excisional surgery for choledochal cyst, because it is possible that cancer associated with the intrapancreatic biliary tract may develop.

Adenocarcinoma↗

Fatty liver suppressed the angiogenesis in liver metastatic lesions.

BACKGROUND/AIMS: We have demonstrated that colorectal cancer with fatty liver had few liver metastases clinically as well as experimentally. In this study, to clarify why colorectal cancer with fatty liver had few liver metastases, we focused on the angiogenesis of carcinomas. METHODOLOGY: The rat colon cancer cells (RCN-9) were injected into 40 rats (the fatty liver group = FL group includes 20 rats, the non-fatty liver group = NFL group includes 20 rats). In each group, the PyNPase (pyrimidine nucleoside phosphorylase) activity in the metastatic lesion of the liver was examined using the high-performance liquid chromatographic method. In addition, the microvessel density in the metastatic lesion of the liver was assessed by Von Willebrand factor-related antigen immunostaining. RESULTS: 1) The PyNPase activity in the FL group was 33.34 +/- 6.27 (microgram FU/mg protein/hr), which was significantly lower than that of the NFL group (49.30 +/- 14.82) (P = 0.0021). 2) Microvessel density in the FL group was 1.845 +/- 0.357 (%), while that in the NFL group was 2.777 +/- 1.371 (%). The microvessel density of the FL group was significantly lower than that of the NFL group (P = 0.0365). 3) The regression coefficient between PyNPase activity and microvessel density was 0.480, which indicated a significant correlation (P = 0.0098). CONCLUSIONS: We think that, in colorectal carcinomas with fatty liver, the decreased activity of PyNPase and the decreased neovascularization in the metastatic lesion are closely related to fewer liver metastasis compared with colorectal cancer patients without fatty liver.

Animals↗