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N Azumi

Publications and source records attributed to N Azumi.

At least 37 records · Page 2Linked to original sources
PubMed1988

Non-small cell lung cancer in autogenous subcutaneous bronchial grafts in dogs.

The progression of preneoplasia into lung cancer can be serially studied in a new canine model that is simpler and more cost effective than previously reported methods of orthotopic endobronchial carcinogenesis. Short segments of bronchus, obtained by pneumonectomy, were placed on the back of 10 dogs in the form of subcutaneous bronchial autografts. These autografts (12 to 14 per dog) became vascularized and lined with normal respiratory epithelium. Four to 12 weeks after autograft implantation, 10% methylcholanthrene in crystalline form was put into 57 autografts and 10% methylcholanthrene in a silicone polymer sustained-release implant was placed into 54 autografts. Ten autografts without carcinogen (one per dog) served as controls. Serial samplings of each autograft during 9 to 97 weeks of carcinogen exposure showed the neoplastic progression from normal bronchial cells to invasive cancer through stages such as atypical squamous metaplasia and carcinoma in situ. To date, cancers have been histologically proved in 60 autografts; 36 were induced by implants and 24 by the crystalline form. Thirty-nine cancers were epidermoid, and the remainder were either adenocarcinomas (n = 3) or poorly differentiated spindle cell cancers (n = 18). The sustained-release implant method resulted in larger autografts with a greater tendency to progress to cancer than the crystalline carcinogens (p greater than 0.025). Therefore, the sustained-release implant is now considered the preferred method. Measurement of nuclear deoxyribonucleic acid by image analysis of nine histologic cancers demonstrated hyperploidy. Deoxyribonucleic acid from the L1 repeated sequence family was demonstrably hypomethylated in spindle cell tumors. Curettement of individual autografts yielded sheets of respiratory epithelium from which 43.5 to 409.5 micrograms of deoxyribonucleic acid was isolated. For the first time, deoxyribonucleic acid from each stage of the neoplastic progression in non-small cell lung cancer is available in adequate quantities for serial biochemical and therapeutic analysis.

Animals↗
PubMed1988

Immunophenotypic diagnosis of leiomyosarcomas and rhabdomyosarcomas with monoclonal antibodies to muscle-specific actin and desmin in formalin-fixed tissue.

Two fibrillary proteins, muscle-specific actin (MSA) and desmin, are found only in cells of smooth and skeletal muscle lineages. Among the monoclonal antibodies (MAbs) to these antigens which we have tested, we found several to be reactive in formalin-fixed, paraffin-embedded sections. This finding widened the possibility of using these MAbs in routine diagnostic surgical pathology for the immunodiagnosis of rhabdomyosarcomas (RMS) and leiomyosarcomas (LMS). We therefore conducted a comparative study of three such MAbs which are available commercially and which we applied to paraffin-embedded, formalin-fixed tissues from 15 patients with RMS and 19 patients with LMS. The case selection criteria included typical light-microscopic appearances as well as immunoreactivity with at least one of the MAbs. MSA was detected in all cases of RMS and LMS, whereas desmin was reactive in 12 of 13 RMS and 10 of the 19 LMS. (Desmin antigenicity was judged to be lost in two RMS, since the vascular smooth-muscle tissue present in the specimens failed to react with these antibodies.) In LMS, desmin tended to show focal positivity, whereas the MSA in the same specimens was diffusely positive. These results demonstrate the utility of MAbs for confirmation of the muscle lineage of LMS and RMS in formalin-fixed, paraffin-embedded tissue. The results also indicate that, with the MAbs tested, the antigenicity of MSA is preserved more consistently than that of desmin in formalin-fixed, paraffin-embedded tissue, and that MSA is a more sensitive marker for the detection of muscle differentiation than is desmin, especially in LMS.

Actins↗
PubMed1987

The cellular composition of adenoid cystic carcinoma. An immunohistochemical study.

To investigate the cellular differentiation of adenoid cystic carcinomas (ACC), a comparative immunohistochemical study of 12 normal salivary glands and eight specimens of ACC was performed. Antibodies were used against S100 protein (S), keratins (K) of various molecular weights, vimentin (V), muscle-specific actin (A), epithelial-membrane antigen, human milk fat globules, and collagen type IV. A panel of four of these antibodies (SKVA) was identified as the most helpful in characterizing cells in normal salivary glands and ACC. The immunophenotypes depended on the histologic patterns of ACC. Cells in morphologically recognizable duct structures in the cribriform and trabecular areas expressed a phenotype similar to that of the intercalated duct. Cell layers around pseudocysts and occasional cellular islands had an immunophenotype suggesting myoepithelial-cell differentiation. The most clear cut epithelial/myoepithelial bilaminar differentiation was present in areas with a trabecular pattern, in which the layers facing the stroma and the central ductal elements had SKVA phenotypes of myoepithelial and ductal differentiation, respectively. In areas with a reticular pattern, most of the cells showed ductal differentiation. Many of the cells in the cribriform and basaloid regions were immunophenotypically undifferentiated. These results indicate that ACC consists of undifferentiated cells and of cells that are differentiating toward ducts, predominantly intercalated ducts, and toward myoepithelium. These findings support previous observations by electron microscope.

Actins↗
PubMed1987

Differential susceptibility to bronchial carcinogenesis in syngeneic hamsters.

Previous studies of chemical carcinogenesis in the lung of Syrian golden hamsters have utilized outbred (nonsyngeneic) animals. Using the endobronchial sustained release implant technique, which causes focally originating cancers in outbred hamsters, we studied the course of bronchial carcinogenesis in two varieties of syngeneic Syrian golden hamsters, the LSH and the F1D strains (BIO 15.16 male X BIO 87.20 female). With either 10% benzo(a)pyrene or 10% methylcholanthrene sustained release implants the time course of epithelial transition from normal to neoplastic was the same for F1D hamsters as previously described for outbred hamsters. Using 10% benzo(a)pyrene sustained release implants the incidence of cancers as a function of time was significantly lower (P less than 0.001) in LSH hamsters as compared to outbred and F1D animals. Of 19 tumors transplanted into syngeneic F1D hamsters, 16 have been successfully propagated by serial transplantation. We conclude that (a) F1D hamsters are comparable to outbred animals in the response of their bronchial epithelium to endobronchial benzo(a)pyrene and methylcholanthrene, (b) there are significant differences in susceptibility to bronchial chemical carcinogenesis among hamster strains, thereby giving opportunity to study potential genetic control mechanisms during bronchial carcinogenesis, and (c) F1D hamsters are suitable for studies of lung cancer biology using tumor transplantation methods.

Animals↗
PubMed1987

The distribution of vimentin and keratin in epithelial and nonepithelial neoplasms. A comprehensive immunohistochemical study on formalin- and alcohol-fixed tumors.

Vimentin has been regarded as the intermediate filament characteristic of normal and neoplastic mesenchymal cells and keratins as typical of epithelial cells and the neoplasms derived from them. However, many epithelial cells in tissue culture or in effusion, as well as cells in some solid epithelial neoplasms such as renal, endometrial, ovarian, pulmonary, and thyroid adenocarcinomas, have been shown to coexpress vimentin and keratin. The recent availability of monoclonal antibodies that work reasonably well in paraffin-embedded tissue led us to carry out a comprehensive immunohistochemical study on formalin- and alcohol-fixed specimens of neoplasms in which we used monoclonal antibodies against vimentin. These results were compared with our previous study in which the same tumor tissues were investigated using antibodies against keratin. The antigenicity of vimentin was found to be preserved in all alcohol-fixed specimens and in 63% of formalin-fixed tissues. Vimentin was the sole intermediate filament present in virtually all sarcomas, meningiomas, schwannomas, and melanomas. In addition, variable percentages (10-57%) of carcinomas, neuroendocrine carcinomas, neuroblastomas, thymomas, and mesotheliomas were positive for vimentin, which, except in the neuroblastomas, was coexpressed with keratins. Among the adenocarcinomas, more than 50% of papillary carcinomas of the thyroid, as well as renal, endometrial, ovarian, and lung carcinomas, coexpressed keratins and vimentin. A distinctive paranuclear and basal localization of vimentin was observed in the cells of many of these tumors, in contrast to the predominantly apical distribution of the keratins. The authors conclude that coexpression of vimentin and keratin is more widespread than previously reported and that antibodies to vimentin, by themselves, are of limited value for the differentiation of epithelial from mesenchymal neoplasms.

Antibodies, Monoclonal↗
PubMed1987

Quantitation of human cytomegalovirus DNA in lungs from bone marrow transplant recipients with interstitial pneumonia.

DNA-DNA hybridization was compared with culture for virus and histopathology for the detection and quantitation of human cytomegalovirus (HCMV) in lungs from bone marrow transplant recipients. The hybridization assay detected 100 pg of HCMV DNA or greater than 520 plaque-forming unit equivalents. Compared with culture for virus, the hybridization assay had a sensitivity of 90.6% and a specificity of 77.8%. The quantity of HCMV DNA and the infectivity titer were directly correlated. Quantitation of HCMV DNA by hybridization was more reproducible than were infectivity titers for frozen specimens. Histopathologic examination of lung specimens detected HCMV inclusions in 60% (15 of 25) of patients with HCMV-associated interstitial pneumonia, whereas hybridization results were positive for 96% (24 of 25) of these patients. A significant inverse correlation was demonstrated between quantitative values for HCMV DNA and the duration of pneumonia.

Bone Marrow Transplantation↗
PubMed1987

Atypical and malignant neoplasms showing lipomatous differentiation. A study of 111 cases.

One-hundred-eleven cases of histopathologically atypical or malignant lipomatous lesions in the somatic soft tissue and retroperitoneum were studied. These consisted of 48 differentiated fatty neoplasms of the somatic soft tissues (DFT-S), 21 fatty neoplasms of the retroperitoneum (DFT-R), 33 myxoid liposarcomas from various sites and nine pleomorphic liposarcomas. DFT-S were defined as lipomatous lesions composed of mature fat and containing atypical stromal cells or lipoblasts. In the somatic soft tissues, this group included lesions that would be classified using published criteria as "atypical lipoma", "pleomorphic lipoma", "well-differentiated lipoma-like liposarcoma", and "sclerosing liposarcoma". All of the DFT-R met previously published criteria for "well differentiated liposarcoma" or "sclerosing liposarcoma". We found no consistent histologic differences between the DFT-S and DRT-R. No pure "round cell" liposarcomas were encountered although many myxoid liposarcomas had "round cell" areas. Follow-up data were available in 80 cases (72%) with a mean follow-up period of over 7 years. Among the DFT-S there were no uncontrollable recurrences, distant metastases, or tumor-related deaths. The depth of the neoplasm correlated with the tendency for local recurrence; no neoplasms primary in the subcutis recurred; 29% of the tumors recurred when they originated in the deep soft tissues or within the muscle. None of the recurrent tumors demonstrated "dedifferentiation." DFT-R had a recurrence rate of 67% and, although there were no distant metastases, nine patients (43%) died of tumor. Five retroperitoneal tumors dedifferentiated but did not metastasize. In light of this experience, we believe that the term "atypical lipoma" is warranted for the DFT-S and "well differentiated liposarcoma" is an appropriate label for the DFT-R. The overall mean survival for the 52 cases of liposarcoma (excluding DFT-S) was 13.6 years. The mean survival in "well differentiated liposarcoma" (11.25 years) was between that for myxoid liposarcoma (16.25 years) and that for pleomorphic liposarcoma (7 years). Six patients (29%) with myxoid liposarcoma developed local recurrences and 6 patients (29%) developed distant metastases and died. Metastasis was always associated with a round cell (or pleomorphic) component with increased numbers of mitotic figures in either the primary tumor or a local recurrence.

Adolescent↗
PubMed1986

Early stage head and neck non-Hodgkin's lymphoma. The effect of tumor burden on prognosis.

Treatment results were investigated in 113 previously untreated patients with clinical Stage I and II (Ann Arbor) non-Hodgkin's lymphoma of the head and neck. Fifty-six Waldeyer's ring, 34 other extranodal sites, and 23 cervical nodal lesions were included. The overall relapse-free survival at 5 years was 41%. Age and Ann Arbor stage influenced relapse-free survival. The results suggested that the tumor cell burden is a fundamental prognostic factor for patients with Waldeyer's ring disease and for patients with only cervical nodal disease. Abdominal relapse was most frequent, followed by generalized relapse. From 1981, patients were randomized in a clinical trial to receive either chemotherapy (cyclophosphamide, vincristine, and prednisone [CVP], five courses) or whole-abdominal irradiation (25 Gy/20 Fr) as an adjuvant therapy. Patients could not tolerate the whole-abdominal irradiation well. A significant improvement in survival has been obtained by adjuvant chemotherapy.

Adolescent↗
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↗