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Biomedical subjects

K Mukai

Publications and source records attributed to K Mukai.

At least 235 records · Page 13Linked to original sources

Primary lymphoma of the common bile duct.

Primary lymphoma of the common bile duct is an extremely rare disease. Only two detailed case reports have been published in the literature. In the present paper, a 68-year-old female with obstructive jaundice and a primary lymphoma of the common bile duct, which was resected, is described in detail because of the rarity of the lesion in the literature. The cholangiogram demonstrated stricture of the common bile duct. The findings at angiography and computed tomography were non-specific, but a hypo-echoic mass filling the lumen of the bile duct was demonstrated by ultrasonography. Subtotal resection of the common bile duct and cholecystectomy was performed as the method of choice, although the frozen section examination was not definitive. The final histological diagnosis was malignant lymphoma of the diffuse, small cleaved cell type. There was no metastasis to dissected regional lymph nodes. External irradiation was effective when recurrent tumors were found six months later. However, the patient developed generalized disease one year after resection. Although combination chemotherapy was effective this time for her lymphadenopathy, she died of pneumonia one year and four months after surgery. It can be postulated that ultrasound would be useful in diagnosing this rare entity, and that adjunctive radiotherapy after resection would be preferable to prevent progression of the disease.

Aged↗

[Postoperative percutaneous coronary angioplasty for stenosed aortocoronary vein bypass].

This paper was presented to demonstrate the efficacy of postoperative PTCA for varying degree of stenosis aortocoronary bypass with saphenous vein grafts. The following conclusions were drown. 1. The success rate of postoperative PTCA for 15 grafts showed 88.8%. 2. The rate of success for PTCA was much more effective in patients within one year after bypass operations. The authors concluded that postoperative PTCA can be done with excellent rate of success. Therefore, postoperative cine-coronary angiography should be done to evaluate the state of the graft and to decide to perform possible postoperative PTCA in order to keep long time patency rate of saphenous vein grafts.

Adult↗

[A case of intraventricular cyst associated with normal pressure hydrocephalic condition].

A case of intraventricular cyst associated with normal pressure hydrocephalic condition (NPHC) is reported. A 72 year-old female, with 2-year-history of slowly progressing dementia and gait disturbance, was admitted to our hospital on September 19, 1989. On admission, she had mild dementia, unsteadiness of gait, and at times urinary incontinence. Cerebrospinal fluid (CSF) pressure was found to be 90mmH2O by lumbar tap. Plain computed tomographic (CT) scan and T1-weighted magnetic resonance image (MRI) showed asymmetrical enlargement of the trigon and posterior horn of the right lateral ventricle. CT cisternography showed a cyst in the trigon and in the posterior horn of the right lateral ventricle. T1-weighted MRI with Gd-DTPA demonstrated no enhancement of the cyst wall, and there was superior and posteromedial displacement of the choroid plexus at the trigon of the right lateral ventricle. The patient was diagnosed as having an intraventricular cyst in the right trigon with NPHC. Ventriculo-peritoneal shunt and partial removal of the cyst were performed. Histological examination of the cyst wall revealed collagenous strands and no epithelial cells. Developmental intracranial cysts, especially arachnoid or ependymal cysts, occasionally lack an epithelial layer, so their histological diagnosis is difficult. This case was considered to be an arachnoid cyst because there was adhesion between the cyst and the choroid plexus in the right trigon, and superior, posteromedial displacement of the choroid plexus, which indicated extension of the cyst from the extracerebral to the intracerebral region. NPHC was considered to be due to disturbance of CSF circulation caused by gradual expansion of the cyst.

Aged↗

[Tumor markers--personal experience. Immunohistochemical markers for cancer diagnosis].

Immunohistochemical tumor markers have been increasingly utilized for histopathological diagnosis. Major applications include: 1) Differential diagnosis of undifferentiated tumors, 2) identification of primary site of metastatic carcinoma of unknown primary, 3) analysis of tumor differentiation, 4) functional study of functioning tumors, and 5) assessment of tumor aggressiveness. Since many antigens can be detected in routinely processed formalin-fixed tumor tissues, immunohistochemistry is a very useful tool to analyze the relationship between phenotypic characteristics and morphology. It is expected that many more immunohistochemical markers will become available for histopathological diagnosis.

Biomarkers, Tumor↗

[An evaluation of excisional biopsy for tongue carcinoma].

An evaluation of excisional biopsy for tongue carcinoma (T1, T2) as a surgical treatment was performed. Forty-seven patients who received excisional biopsy among 394 patients with tongue carcinoma (T1, T2) treated in National Cancer Center Hospital during 24 years were examined. These patients were divided into following three groups: group a) patients treated with excisional biopsy only, group b) those treated with excisional biopsy and cryosurgery, group c) those treated with excisional biopsy and radiotherapy. We examined local control rate of these groups, degree of differentiation in histopathological examination, and median cancer free surgical margin. From these we obtained following results: 1) There was no significance in local control rate among these three groups (group a 77%, group b 84%, group c 45%) 2) There were no local recurrences in the patients with cancer free margin of 5 mm or more except when the histopathology showed perineural invasion, lymphatic vessel invasion, and/or deep invasion to the muscle. 3) Even if we had cancer positive surgical margin with excisional biopsy, we could obtain high local control rate (75%) with additional cryosurgery. We conclude that excisional biopsy for tongue carcinoma (T1, T2) is a good method for primary therapy.

Adult↗

Isolation and phosphorylation of the Bacillus subtilis degS and degU gene products.

The Bacillus subtilis sacU locus consists of two genes, degS and degU, which positively regulate the synthesis of several extracellular enzymes including the neutral and alkaline proteases. Both the DegS and DegU proteins have been purified from overproducing Escherichia coli strains harboring degS or degU gene-carrying plasmids, and the following results were obtained. DegS was autophosphorylated in the presence of [gamma-32P]ATP, and transferred the phosphoryl group to DegU. The transfer reaction was rapid in contrast to the autophosphorylation reaction. The phosphoryl groups incorporated into DegS and DegU were released at their own specific rates, the latter being twice faster than the former. The linkage between DegS and the phosphoryl moiety was unstable at acidic pH, whereas reverse was the case for the linkage between DegU and its phosphoryl group, suggesting that His and Asp are involved in the formation of DegS-phosphate and DegU-phosphate, respectively. Deletion of degS resulted in the reduced expression of the exocellular alkaline protease gene, aprE. These results suggest that phosphorylation of DegS by its own kinase activity and subsequent transfer of the phosphoryl group to DegU play a role in the activation of the aprE gene.

Adenosine Triphosphate↗

Stopped-flow investigation of antioxidant activity of estrogens in solution.

A kinetic study of the reaction between estrogens (female hormone) and substituted phenoxyl radical has been performed, as a model for the reactions of estrogens with lipid peroxyl radical in biological systems. The rates of reaction of estrogens (estrone 1, estradiol 2, 2-methoxyestrone 3, 3-methoxyestrone 4, and 2-hydroxyestrone 5) with substituted phenoxyl radical in benzene have been determined spectrophotometrically, using stopped-flow technique. The second-order rate constants, k2, obtained are 84 M-1.s-1 for 1, 138 M-1.s-1 for 2, 520 M-1.s-1 for 3, less than 10(-4) M-1.s-1 for 4, and 2.6 X 10(5) M-1.s-1 for 5 at 25.0 degrees C. 2-Hydroxyestrone 5 was found to be 2.9-times more active than alpha-tocopherol, which has the highest antioxidant activity among natural tocopherols. The order of magnitude of k2 value (1 less than 2 less than 3 less than alpha-Toc less than 5) is in agreement with that of in vitro tests of their antioxidant activities, as measured by the inhibition of lipid peroxidation. Further, similar measurements have been performed for the reaction between the above estrogens 1-5 and tocopheroxyl 6 in benzene solution. It was found that the estrogens having an OH group at the aromatic ring have an ability to regenerate the tocopheroxyl 6 to tocopherol. Especially, the 2-hydroxyestrone 5 showed about three orders of magnitude higher reactivity than ascorbic acid.

Antioxidants↗

Stopped-flow kinetic study of the regeneration reaction of tocopheroxyl radical by reduced ubiquinone-10 in solution.

Kinetic study of the reaction between tocopheroxyl (vitamin E radical) and ubiquinol-10 (reduced ubiquinone, n = 10) has been performed. The rates of reaction of ubiquinol with alpha-tocopheroxyl 1 and seven kinds of alkyl substituted tocopheroxyl radicals 2-8 in solution have been determined spectrophotometrically, using a stopped-flow technique. The result shows that the rate constants decrease as the total electron-donating capacity of the alkyl substituents on the aromatic ring of tocopheroxyls increases. For the tocopheroxyls with two alkyl substituents at ortho positions (C-5 and C-7), the second-order rate constants, k1, obtained vary in the order of 10(2), and decrease predominantly, as the size of two ortho-alkyl groups (methyl, ethyl, isopropyl and tert-butyl) in tocopheroxyl increases. On the other hand, the reaction between tocopheroxyl and ubiquinone-10 (oxidized ubiquinone) has not been observed. The result indicates that ubiquinol-10 regenerates tocopherol by donating a hydrogen atom of the 1-OH and/or 4-OH group to the tocopheroxyl radical. For instance, the k1 values obtained for alpha-tocopheroxyl are 3.74 x 10(5) M-1.s-1 and 2.15 x 10(5) M-1.s-1 in benzene and ethanol solution at 25 degrees C, respectively. The above reaction rates, k1, obtained were compared with those of vitamin C with alpha-tocopheroxyl reported by Packer et al. (k2 = 1.55 x 10(6) M-1.s-1) and Scarpa et al. (k2 = 2 x 10(5) M-1.s-1), which is well known as a usual regeneration reaction of tocopheroxyl in biomembrane systems. The result suggests that ubiquinol-10 also regenerates the tocopheroxyl to tocopherol and prevents lipid peroxidation in various tissues and mitochondria.

Antioxidants↗

Spontaneous transformation and immortalization of human endothelial cells.

A new cell line from the human umbilical vein has been established and maintained for more than 5 yr (180 generations; 900 population doublings). This strain, designated ECV304, is characterized by a cobblestone monolayer growth pattern, high proliferative potential without any specific growth factor requirement, and anchorage dependency with contact inhibition. Karyotype analysis of this cell line reveals it to be of human chromosomal constitution with a high trisomic karyotype (mode 80). Ultrastructurally, endothelium-specific Weibel-Palade bodies were identified. Although one of the endothelial cell markers, Factor VIII-related antigen (VIIIR:Ag) was negative in this cell line, immunocytochemical staining for the lectin Ulex europaeus I (UEA-I), and PHM5 (anti-human endothelium as well as glomerular epithelium monoclonal antibody) was positive, and angiotensin-converting enzyme (ACE) activity was also demonstrated. In addition, ECV304 displayed negativity for alkaline and acid phosphatase and for the epithelial marker keratin. All of these findings suggest that ECV304 cells originated from umbilical vein endothelial cells by spontaneous transformation. Ultrastructurally, no viruslike particles have been detected intracellularly. Nude mouse tumorigenicity and rabbit cornea tests were both positive. This is a report on a novel case of phenotypic alteration of normal venous endothelial cells of human origin in vitro, and generation of a transformant with indefinite life spans. This line may be useful in studies of some physiologically active factors available for medical use.

Cell Division↗

Expression of ras p21 protein by thymoma.

Histopathological examination of thymomas often fails to predict their malignant potential because the morphology of invasive or metastatic thymomas does not differ significantly from that of benign, encapsulated thymomas. In order to find a marker of aggressiveness in thymomas, 21 cases (9 non-invasive, 8 invasive and 4 metastatic thymomas) were examined for expression of the ras oncogene product p21 by immunohistochemistry and immunoblot analysis. Immunohistochemical study, using a serially diluted monoclonal antibody, NCC-RAS-001, demonstrated that neoplastic thymoma cells generally contained more p21 than normal thymic epithelial cells. Immunoblot analysis using another monoclonal antibody (NCC-RAS-004) also confirmed the increased concentration of p21 in all but one of the thymomas by comparison with normal thymic tissue. One metastatic thymoma did not have a band of p21 recognized by NCC-RAS-004 and was believed to have a deletion of the epitope recognized by this antibody. In addition, another metastatic thymoma showed abnormal electrophoretic mobility of p21. The increased amount of p21 in thymomas suggests that this protein has a role in the oncogenesis or progression of thymoma. The high incidence of a p21 molecular abnormality in metastatic thymomas indicates that the abnormality of this protein could be used as a possible marker of aggressive behavior.

Antibodies, Monoclonal↗

The methanol-oxidizing system of Methylobacterium extorquens AM1 reconstituted with purified constituents.

The electron transport system (with cytochrome aa3) coupled to the oxidation of methanol in Methylobacterium extorquens AM1 (former Pseudomonas AM1) was reconstituted with highly purified constituents of the system. A mixture of 2.7 microM methanol dehydrogenase, 3.2 microM cytochrome cH, and 71 nM cytochrome c oxidase (= cytochrome aa3) consumed oxygen at a lower rate in the presence of methanol, while its activity was enhanced 3-fold by the addition of 1.4 microM cytochrome cL (74 mol of O2 consumed/mol of heme a of cytochrome c oxidase per min). Further addition of amicyanin to the above mixture did not affect the activity. Although ammonium ion greatly activated the activity of methanol dehydrogenase, the ion had little effect on the oxygen consumption activity of the above mixture. On the basis of the results obtained in the present study, an electron transport system is proposed for the oxidation of methanol in M. extorquens AM1.

Alcohol Oxidoreductases↗

Heterogeneity of proliferative activity in nodule-in-nodule lesions of small hepatocellular carcinoma.

Surgically resected small hepatocellular carcinomas showing "nodule-in-nodule" formation were analyzed in terms of cell proliferative activity. The analysis was achieved by successful immunohistochemical demonstration of proliferating cell nuclear antigen in formalin-fixed paraffin-embedded tissue sections. Eight nodules (up to 3 cm in diameter) examined were either atypical adenomatous hyperplasia or hepatocellular carcinoma of low histologic grade, containing a discrete inner nodular area composed of obvious hepatocellular carcinoma of higher histologic grade. In all cases, the proliferating cell nuclear antigen labeling index of the latter area was much higher than that of the former, which in turn was slightly higher than that of the non-cancerous liver of the patient in 6 cases. The data presented here provide supporting evidence that the successive emergence and expansion of a more rapidly proliferating subclone within a nodule result in the stepwise progression of malignancy of human hepatocellular carcinoma.

Antigens, Neoplasm↗

Detection of Epstein-Barr virus DNA in Reed-Sternberg cells of Hodgkin's disease using the polymerase chain reaction and in situ hybridization.

Thirty-one cases of Hodgkin's disease were examined for the occurrence of Epstein-Barr virus (EBV) genome by using the polymerase chain reaction (PCR) of DNA in formalin-fixed paraffin-embedded tissues and in situ hybridization technique. The cases were subdivided into 17 cases of nodular sclerosis (NS), nine cases of mixed cellularity (MC), four cases of lymphocyte predominance (LP), and one case of lymphocyte depletion (LD). EBV DNA was detected in eight cases including four cases of NS, three cases of MC and one case of LP. The sensitivity of PCR was higher than that of Southern blot hybridization of DNA from fresh frozen tissue, because Southern blot hybridization using the BamHI-W fragment of EBV detected virus DNA only in two of three cases which were positive by PCR. The results of in situ hybridization studies confirmed that EBV genome was localized within the nuclei of Reed-Sternberg (RS) cells and their mononuclear variants. Furthermore, double-labeling studies combining in situ hybridization and immunocytochemistry using CD30 (BerH2) and CD15 (LeuM1) as markers of RS cells, as well as pan B-marker (L26) and pan T-marker, CD45RO (UCHL1), were performed to demonstrate the phenotype of EBV DNA-positive cells, confirming that EBV DNA was present in RS cells but not in lymphocytes. The results of this study indicate a significant association between EBV and some cases of Hodgkin's disease.

Adult↗

Alveolar soft part sarcoma. A clinicopathologic and immunohistochemical study of 12 cases.

Twelve cases of alveolar soft part sarcoma (ASPS) were reviewed. Seven of them arose primarily in the lower extremities, three in the head and neck region, and two in other parts. ASPSs in the head and neck region occurred in children before 10 years of age, whereas ASPSs in the other regions occurred in rather older patients. Moreover, ASPSs of the head and neck were relatively small in size, and were diagnosed earlier than those in other regions. Histologically, six cases (including all the head and neck cases) contained considerable area of small and indistinct alveolar structures. Four cases showed remarkable cellular pleomorphism. Immunohistochemical demonstration of vimentin, desmin, the beta-subunit of enolase and the MM isozyme of creatine kinase, together with the absence of immunoreactive cytokeratin, supported the myogenic nature of this rare tumor. A small number of S-100 protein-positive tumor cells were also observed. Follow-up data for these cases disclosed that the tumors containing considerable area of small alveoli and uniform small tumor cells formed distant metastases at an early stage.

Adolescent↗

Transferrin receptor expression in adenocarcinoma of the lung as a histopathologic indicator of prognosis.

Immunohistochemical reactivity with OKT9 (antitransferrin receptor) monoclonal antibody was studied in 58 surgically resected adenocarcinomas of the lung. The cell surface and cytoplasm of the tumor cells were stained in 44 cases (76 percent). The expression of the transferrin receptor (TrfR) in tumor cells was compared with histopathologic prognostic factors, such as TNM factors, degree of histologic differentiation, degree of nuclear atypia, and frequency of mitotic figures. The expression of TrfR showed significant correlation with the degree of histopathologic differentiation (p less than 0.025), degree of nuclear atypia (p less than 0.025), and frequency of mitotic figures (p less than 0.001). However, there was no definite correlation with TNM factors. These results indicate that the expression of the TrfR in pulmonary adenocarcinoma corresponds to the elevated proliferative activity of the tumor cells, and that immunohistochemical reactivity with OKT9 can be used as one of the histopathologic indicators of prognosis of pulmonary adenocarcinoma.

Adenocarcinoma↗

Spinal cord glioblastoma multiforme with intracranial dissemination--case report.

A case of spinal cord glioblastoma multiforme with intracranial dissemination is reported. A 23-year-old female was admitted to a local hospital complaining of lumbago. Myelography revealed an intramedullary thoracic tumor. The tumor was partially removed through a laminectomy at Th11-L1. The histological diagnosis was glioblastoma multiforme, and focal irradiation (total 50 Gy) was given. Eight months after the operation, symptoms of increased intracranial pressure appeared. Computed tomographic (CT) scans showed marked hydrocephalus, and multiple tumors at anterior horns of bilateral lateral ventricles. A ventriculoperitoneal shunt and an Ommaya reservoir into the left lateral ventricle were emplaced. Three months later, she was transferred to our hospital. CT scans showed enhanced lesions in the fourth ventricle, anterior horn of the left lateral ventricle, septum pellucidum, and pituitary gland. Suboccipital craniectomy was performed, and the mass around the fourth ventricle was partially removed. Histological examination of the tumor specimens showed glioblastoma multiforme. Postoperatively, she received whole brain irradiation (total 50 Gy), and intrathecal injection of beta-interferon via the Ommaya reservoir. However, she died of respiratory insufficiency. It is considered that the spinal cord glioblastoma multiforme disseminated into the intracranial space.

Adult↗

CT of hilar cholangiocarcinoma: late contrast enhancement in six patients.

Hilar cholangiocarcinoma usually appears on CT scans as a low-density or isodense mass that abruptly obstructs converging dilated bile ducts. In four of six patients with histopathologically proved hilar cholangiocarcinoma who had late enhanced CT 8-15 min after dynamic CT, the lesion was seen as a high-density mass instead of the low-density lesion seen earlier on unenhanced and dynamic CT scans. The other two patients had ring enhancement with evidence of a thickened wall of the bile duct both on early and late enhanced CT scans. In the first four patients, carcinoma invaded the neighboring hepatic parenchyma and produced a mass, whereas in the last two, carcinoma was localized in the wall of the bile duct. Histopathologically, all lesions consisted of adenocarcinoma associated with a dense fibrotic tissue. As late enhanced CT shows hilar cholangiocarcinoma as a high-density mass, the exact location of the tumor and its relation to neighboring vessels can be determined, especially in relatively small tumors, and differentiation from sclerosing cholangitis is possible.

Adenoma, Bile Duct↗