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Biomedical subjects

N Azumi

Publications and source records attributed to N Azumi.

At least 73 records · Page 4Linked to original sources
PubMed1986

Tumor DNA content in primary and metastatic colorectal carcinoma.

We performed this study to determine if tumor DNA content was an independent prognostic indicator in patients with primary tumors or hepatic metastases from colorectal cancer. We analyzed tumor DNA content by flow cytometry from paraffin-embedded specimens in 133 patients. In the 77 patients with primary colorectal cancer who had had "curative" resection, DNA content of the tumor was an independent prognostic indicator in predicting both relapse-free and overall survival. Logistics regression analysis demonstrated that aneuploidy, ie, tumors that exhibited a population of cells with an "abnormal" DNA content, was the single most important variable in predicting both recurrence and death from disease, even more important than stage. However, in 56 patients with hepatic metastases from colorectal cancer, the DNA content of the liver metastases bore no relationship to the patients' survival or their response to therapy. These data suggest that tumor DNA content is an important prognostic indicator in patients with primary colorectal carcinoma but does not reflect the natural history of patients with liver metastases.

Colonic Neoplasms↗
PubMed1986

Mucormycosis in diabetic ketoacidosis. Role of unbound iron binding capacity of transferrin.

Increased susceptibility to Rhizopus oryzae in diabetes was investigated using mice in which diabetic ketoacidosis was experimentally induced. All of the diabetic mice which had developed ketoacidosis died within four days after inoculation of R. oryzae and their serum UIBCs (Unbound iron binding capacity) were significantly lower than those of the normal control mice. This study suggested that the decreased serum UIBC produced by diabetic ketoacidosis enhances the growth of R. oryzae in vivo.

Animals↗
PubMed1986

Carcinogenesis in heterotopic respiratory epithelium in canine subcutaneous bronchial autografts.

Short bronchial segments obtained by pneumonectomy were implanted, 9-12 per dog, in the subcutaneous tissues of the back of seven dogs. These subcutaneous bronchial autografts (SBA) became vascularized, and they contained viable, histologically normal respiratory epithelium 4 wk after implantation. From 1-3 mo after implantation, 10% methylcholanthrene in steroid suspension medium was instilled into 21 SBAs, and 10% methylcholanthrene in a silicone polymer sustained release implant was placed in 22 SBAs. Ten SBAs were left carcinogen free as controls. SBA contents were examined cytologically at 3-mo intervals. Biopsies were done from 2-32 mo after carcinogen implantation. Progressive preneoplastic changes were noted in all five dogs which received carcinogen. Curetments of five SBAs after 14-mo exposure to methylcholanthrene yielded 10(4)-10(5) cells from each SBA; 40-70% of the cells obtained were at the same stage of atypical squamous metaplasia. At least one SBA in each dog yielded cancer cells by cytological criteria by 19-29 mo after instillation. Biopsy of a grossly abnormal SBA revealed well-differentiated epidermoid carcinoma at 32 mo. The multiple SBA method provides isolated portions of canine respiratory epithelium for the study of chemical carcinogenesis and for the production of sizable preneoplastic cell populations.

Animals↗
PubMed1986

Endobronchial carcinogenesis in dogs.

A canine model of squamous cell lung cancer has been developed through studies with 110 dogs exposed by 11 focal endobronchial regimens to chemical carcinogens: benzo(a)pyrene, nitrosomethylurea, methylcholanthrene, and dimethylbenzanthracene. A combination of nitrosomethylurea and benzo(a)pyrene caused the first invasive cancer after 5.5 years. Toxic side-effects resulted from either nitrosomethylurea or high-dose dimethylbenzanthracene given by bronchial submucosal injection and from adjuvant immunosuppression with azathioprine and corticosteroids. Four regimens in 58 dogs caused 31 cancers, including five T1-2 N0 M0 cancers, 17 metastasizing carcinomas, and nine carcinomas of lesser stages. The following regimens caused cancers: sequential benzo(a)pyrene, nitrosomethylurea, and yttrium 91; benzo(a)pyrene and topical nitrosomethylurea; low-dose dimethylbenzanthracene; high-dose methylcholanthrene. The most suitable regimen to date has been 30 mg of methylcholanthrene given by submucosal injection every 2 to 3 weeks; this produced cancers at preselected sites within 2 years of first exposure in eight of 10 dogs. The neoplastic continuum has followed a predictable, reproducible sequence that regularly began with epithelial hyperplasia. Squamous metaplasia occurred in 6 to 18 weeks; it was followed by progressive squamous atypia. The interval until invasive cancer developed varied with the regimen employed; it was about 20 months with methylcholanthrene. Serial cytologic specimens, studied by image analysis, revealed progressive increase in mean total cellular deoxyribonucleic acid content from diploid in normal cells to greater than tetraploid in cancer cells (p less than 0.01). We have recently been successful with serial passage of four canine lung cancers from four to twelve transplant generations in nude mice. There is now a predictable large animal model of squamous cell lung carcinoma at preselected site(s) that closely resembles human lung cancer. The preneoplastic period is short enough to be fiscally defensible, but long enough to permit study of the biologic changes during endobronchial carcinogenesis.

Adenocarcinoma↗
PubMed1985

Experimental candidiasis in iron overload.

In an attempt to study the influence of iron overload on deep mycotic infection, experimental candidiasis was induced in mice. One group received intravenous injections of colloidal iron (60 mg/kg weight) for three consecutive days before intravenous inoculation of Candida albicans spores (1 X 10(7). The other received the same number of Candida spores without iron overload. The animals in both groups were observed for 28 days. The Candida lesions, regardless of iron administration, were located mainly in the kidney. There was a marked difference in mortality between the two groups, i.e., 40% in the group without iron administration and 80% in the group with it. The higher mortality rate in the latter group may be explained by following reasons: increased serum iron and iron saturation (iron is essential to the growth of Candida), decreased phagocytic activity against intravenously inoculated Candida because of the saturation of the phagocytic cells by the preceding colloidal iron administration and enhanced proliferation of Candida, which tends to involve the kidney, exposed to abundant iron in the kidney due to increased excretion. The current experiment showed that excessive iron clearly promoted the proliferation of intravenously inoculated Candida in vivo.

Animals↗
PubMed1985

Islet cell isolation in experimental d,l-ethionine pancreatitis in dogs.

Bulk isolation of islets of Langerhans for biochemical studies or transplantation has generally been associated with significant or even prohibitive contamination by acinar tissue. High-purity islet preparations are associated with an extremely low yield. The acinar tissue can be ablated with d,l-ethionine, but previously, this tactic has been restricted to rodents because of toxicity problems in larger animals. A dosage regimen in dogs which reduces amylase content of the pancreas to 0.3% of normal with complete preservation of insulin content is reported. Ductal perfusion with collagenase permits the recovery of 45% of the islet cell mass as determined by extractable insulin. These islets prove functional in in vitro perifusion studies and in allografts.

Amylases↗
PubMed1985

Gastric small-cell undifferentiated carcinoma with adeno and squamous cell carcinoma components.

A unique gastric tumor is reported. A large portion of the tumor consisted of a diffuse sheet of undifferentiated cells reminiscent of a small cell undifferentiated carcinoma. The tumor cells showed a few dense core granules and a poorly developed attachment apparatus by electron microscopy. In addition, small portions of the tumor showed adenocarcinoma and squamous cell carcinoma. Another noteworthy finding was that some of the metastatic hepatic nodules consisted of relatively monotonous polygonal cells with a distinct cord-like pattern showing argentaffinity and argyrophilia which were indicative of an atypical carcinoid. This case is a rare example of a gastric tumor with differentiation towards endocrine as well as adeno and squamous cell carcinoma.

Adenocarcinoma↗
PubMed1985

Multiple primary malignant fibrous histiocytoma of the stomach and small intestine.

A case of multicentric malignant fibrous histiocytoma of the stomach and small intestine is reported. The patient was a 60-year-old man who had total gastrectomy under an impression of a gastric carcinoma. The resected stomach revealed a large polypoid mass in the antral portion at the greater curvature. Three months later, he developed ileus and an 80 cm segment of the jejunum was removed. It contained two polypoid masses identical to that seen in the stomach. The tumors showed, in addition to the characteristic light microscopic appearances, strong positivity for alpha-1-antitrypsin by an immunoperoxidase technique, indicating the diagnosis of malignant fibrous histiocytoma (MFH). Electron microscopic findings were also consistent with MFH. We believe that this is the first well-documented case of MFH arising from the stomach and small intestine, to the best of our knowledge.

Antigens↗
PubMed1984

Primary prostatic carcinoid tumor with intracytoplasmic prostatic acid phosphatase and prostate-specific antigen.

A case of prostatic carcinoid tumor with lymph node metastases is reported. The patient was a 78-year-old male who died in ventricular fibrillation. At autopsy, a 2 X 2 cm, white, irregular tumor was found in the prostate and there were several enlarged para-aortic lymph nodes. Both specimens contained a characteristic carcinoid tumor. Argyrophil stains revealed strong positivity in the primary as well as in the metastatic tumors. Electron micrographs prepared from formalin-fixed tissue demonstrated numerous membrane-bound dense-core granules. Immunoperoxidase-labeled antibodies against both prostatic acid phosphatase and prostate-specific antigen localized in the tumor cells. The ultrastructural and immunohistochemical results support differentiation of the tumor cells toward both prostatic epithelial cells and endocrine cells. We believe that this is the first reported case of a prostatic carcinoid tumor in which specific prostatic tissue markers have been demonstrated in the tumor cells.

Acid Phosphatase↗
PubMed1984

Disseminated fungal infection. A review of 20 autopsy cases.

In the study of disseminated fungal infection, in consecutive autopsy cases between 1974 and 1982, we have found this infection in 20 cases (2.55% in all autopsy cases and 16.8% of deep-seated fungal infection). Candidiasis was present in 11 cases, aspergillosis in 8 cases, and mucormycosis and cryptococcosis in 1 case each. One case showed the disseminated infection by both Candida and Aspergillus. All of the 20 cases had underlying disorders. Hematologic disorders were most frequent and were present in 15 cases. In contrast to the small yellow disseminated foci of candidiasis, the lesion by Aspergillus and Mucor were relatively larger, hemorrhagic, and necrotic. Cryptococcal lesion showed a small gelatinous appearance. All of the fungal lesion were devoid of significant inflammatory reaction. Lymphocytopenia (less than 500/mm3) was present in 13 cases out of 16 cases (not examined in the remaining 4 cases). Eight cases had long-standing indwelling intravenous catheters, including two cases in which the catheters apparently played an important role in the development of disseminated candidiasis. Ante-mortem diagnosis was established or suspected in only seven cases. Possible means of the prevention of fungal infection is also discussed.

Adolescent↗
PubMed1984

So-called nasal glioma.

Nasal glioma is heterotopic brain tissue which usually presents as a tumor around the nose of children and infants. We have encountered two cases of nasal glioma during the past nine years at Hokkaido University Hospital. One showed a tumor in the subcutis of the nasal bridge and the other a polypoid mass arising in the soft palate. Both consisted of proliferation of fibrillary spindle cells consistent with fibrillary astrocytes divided by fibrovascular septa. This was reminiscent of "gliosis" of the central nervous system. Occasional protoplasmic astrocytes were present in both and, in addition, one case showed neuronal cells and choroid plexus. The glial nature of the lesion was confirmed by the presence of glial fibrillary acidic protein demonstrated by the immunoperoxidase method. Nasal glioma is not neoplastic contrary to its name and is considered heterotopic brain tissue which was displaced during fetal development by similar pathogenetic mechanisms of sincipital and basal encephalocele, although its communication to the brain was lost.

Astrocytes↗
PubMed1984

Systemic amyloidosis associated with factor X deficiency.

An autopsy case of amyloidosis associated with factor X deficiency is reported. The patient showed a markedly decreased level of factor X (9% normal) and an extremely shortened half-life of intravenously infused factor X. Amyloid deposition was present in most of the visceral organs with special involvement of the liver and spleen. The amyloid in this case was thought to be AL protein, since it was potassium-permanganate-resistant and a small amount of Bence Jones protein was detected after dimethyl sulfoxide therapy. Electron microscopic study revealed a typical appearance of amyloid fibrils radiating from invaginated cell membrane of Kupffer cells, which may indicate rather rapid turnover of the amyloid. Rapidity and severity of amyloid deposition, especially in the liver and spleen, may play an important role in the development of the factor X deficiency associated with systemic amyloidosis.

Amyloid↗
PubMed1983

Islet recovery in chronic pancreatitis.

Chronic pancreatitis ablates a large majority of the acinar tissue which otherwise is a troublesome contaminant in preparing islet cells from higher mammals. Chronic pancreatitis was induced by dividing all pancreatic attachments to the duodenum, including major and minor ducts, in six dogs. After 10 weeks, biopsy of the pancreas showed marked acinar cell atrophy and fibrosis with preservation and even proliferation of islet cells. Intravenous glucose tolerance testing revealed only a minor decrease in K value from 3.4 +/- 1.0 to 2.1 +/- 0.4 during 10 weeks. All dogs then underwent total pancreatectomy and islet autotransplantation. The pancreas was dispersed to a cell suspension by perfusing the pancreatic ducts with collagenase until tissue integrity failed. The digested tissue was then chopped, dissociated by shaking, and filtered. The average cell yield from the pancreas was 7.6 X 10(7) cells of which greater than 95% were islet cells. Acid alcohol-extracted insulin values suggested an average 7% recovery of insulin content and essentially complete elimination of amylase content was demonstrated.

Amylases↗
PubMed1983

Clear cell sarcoma of tendons and aponeuroses: electron microscopic findings suggesting Schwann cell differentiation.

A case of clear cell sarcoma of tendons and aponeuroses arising in the elbow of a young woman is reported. Local recurrence and lymph node metastases occurred despite radiation therapy, chemotherapy, and amputation of the right arm, and the patient died of the tumor approximately ten months after the initial diagnosis. Although melanin was not observed histologically, electron microscopic studies revealed immature melanosomes. In addition, well-developed and duplicated basement membranes, and abundant intracytoplasmic microfibrils suggested melanotic Schwann cell differentiation. On sections stained immunohistochemically, S-l00 protein was present focally. The six previously reported cases of clear cell sarcoma studied electron microscopically are reviewed.

Adult↗