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Biomedical subjects

K Mukai

Publications and source records attributed to K Mukai.

At least 253 records · Page 14Linked to original sources
PubMed1990

An immunohistochemical study of thymic epithelial tumors. III. The distribution of interdigitating reticulum cells and S-100 beta-positive small lymphocytes.

We report an immunohistochemical study of the distribution and number of interdigitating reticulum cells (IDC) and S-100 beta-positive small lymphocytes (S-100 beta + lymphocytes) in 53 thymomas and 11 thymic carcinomas. All 53 thymomas showed the presence of IDC in the tumor parenchyma. In most cases of predominantly lymphocytic and mixed-type thymoma, IDC clustered in areas, that corresponded to locations that had medullary differentiation and contained accumulated mature lymphocytes. By contrast, in most of the predominantly epithelial-type thymomas, IDC were scattered rather than forming clusters. The distribution and number of IDC were correlation with the histological type of thymoma but not with invasiveness. In thymic carcinomas, IDC were scattered in tumor nests. In 47 of the 53 thymomas (89%), infiltrating S-100 beta + lymphocytes were readily recognized. The remaining six cases without S-100 beta + lymphocytes were noninvasive thymoma. We conclude that the degree of S-100 beta + lymphocyte infiltration is correlated with the stage of thymoma and may be a marker of thymoma malignancy.

Adult↗
PubMed1990

The AMeX method: a multipurpose tissue-processing and paraffin-embedding method. II. Extraction of spooled DNA and its application to Southern blot hybridization analysis.

In our previous report, we described a new fixation and paraffin-embedding method (the AMeX method) that preserves many of the antigens that are normally destroyed by routine formalin fixation. The current study was conducted to examine the preservation of high-molecular-weight DNA in tissues processed by this method. DNA was extracted from AMeX-processed tissue sections after deparaffinization by the same method as that used to extract DNA from fresh tissues. The total amounts of DNA extracted from 10 mg each in wet weight of AMeX-processed and fresh mouse liver tissues were identical. In tissues of malignant lymphoma, the total amount of spooled DNA extracted from 50 sections, each 20 microns thick, was about 8 micrograms/mm2. The electrophoretic pattern of DNA digested with restriction endonucleases on agarose gel from AMeX-processed tissue sections did not differ from that of fresh materials. Southern blot hybridization analysis also revealed that the mobility of specific DNA fragments was identical for AMeX-processed and fresh tissues. The AMeX method was thus proved to be a versatile multipurpose tissue-processing procedure, which is expected to provide important information regarding the correlation between morphology, phenotypic expression, and gene alteration.

Blotting, Southern↗
PubMed1989

DNA cytofluorometric and nuclear morphometric analyses of lung adenocarcinoma.

The nuclear DNA content of tumor cells in imprint smears prepared from 72 surgically resected adenocarcinomas of the lung was determined prospectively by means of cytofluorometry, and its relationship to pathologic stage, degree of histologic differentiation, and nuclear atypia represented by the mean nuclear area (MNA) and standard deviation of the nuclear area (SDNA) was studied. The mean nuclear DNA content (MNDC) of poorly differentiated adenocarcinomas was significantly larger than that of well-differentiated adenocarcinomas both in Stages I + II and III + IV (P less than 0.001, each), and the MNDC of Stages III + IV was significantly larger than that of I + II in poorly differentiated adenocarcinomas (P less than 0.01). There was a tendency for histogram Patterns III and IV, in which more aneuploid cells were present than in I and II, to be more common and for the incidence of the aneuploid stem cell line to be higher in less differentiated and more advanced adenocarcinomas, although the differences were not significant statistically. Furthermore, there were significant positive correlations between MNDC and MNA (P less than 0.01) and between MNDC and SDNA (P less than 0.05). The averages of the MNA according to the histogram pattern increased significantly in the increasing order of Patterns I to IV. These results indicate that the nuclear DNA content increases in less differentiated and more advanced adenocarcinomas, and that the nuclear atypia is reflected in abnormal nuclear DNA content (DNA aneuploidy).

Adenocarcinoma↗
PubMed1989

Kinetic study of the reaction of vitamin C with vitamin E radicals (tocopheroxyls) in solution.

New stable vitamin E radicals (7-tert-butyl-5-isopropyltocopheroxyl (4), 5,7-diisopropyltocopheroxyl (5), 7-tert-butyl-5-methyltocopheroxyl (6), and 5,7-diethyltocopheroxyl (7] with two bulky alkyl substituents at ortho positions (C-5 and C-7) have been prepared, and the reaction rates of vitamin C (ascorbic acid (1) and 6-O-stearyl ascorbic acid (2] with these tocopheroxyl radicals in benzene/ethanol/water (2:1:0.1, v/v) solution have been determined spectrophotometrically, using a stopped-flow technique. The second-order rate constants, k2, obtained vary in the order of 10(3), and decrease dramatically in the order 7 greater than 6 greater than 5 greater than 4, as the size of two ortho-alkyl groups in tocopheroxyl increases. The result suggests that the effect of steric hindrance on the reaction rate is considerable. These reaction rates were compared with those of vitamin C with alpha-tocopheroxyl reported by Packer et al. (Nature 278 (1979) 737-738) and Scarpa et al. (Biochim. Biophys. Acta 801 (1984) 215-219).

Ascorbic Acid↗
PubMed1989

An atypical heme-binding structure of cytochrome c1 of Euglena gracilis mitochondrial complex III.

Complex III was purified from submitochondrial particles prepared from Euglena gracilis. The purified complex consisted of 10 subunits and lost antimycin sensitivity. The Euglena complex III showed an atypical difference absorption spectrum for cytochrome c1 with its alpha-band maximum at 561 nm. The pyridine ferrohemochrome prepared from covalently bound heme in the Euglena complex III had an alpha-peak at 553 nm. This wavelength is the same as that of pyridine ferrohemochrome prepared from Euglena mitochondrial cytochrome c (c-558), the heme of which is linked to only a single cysteine residue through a thioether bond. Cytochrome c1 which was a heme-stained subunit with a molecular mass of 32.5 kDa was isolated from the purified complex III and its N-terminal sequence of 46 amino acids was determined. On the basis of apparent homologies to cytochromes c1 from other sources, this sequence included the heme-binding region. However, the amino acid at position 36, corresponding to the first cysteine involved in heme linkage in other cytochromes c1, was phenylalanine. Position 39, corresponding to the second cysteine, was not identified despite the treatment for removal of the heme and carboxymethylation of the expected cysteine. The unidentified amino acid is assumed to be a derivative of cysteine to which the heme is linked through a single thioether bond. The histidine-40 corresponding to the probable fifth ligand for heme iron was conserved in Euglena cytochrome c1.

Amino Acid Sequence↗
PubMed1989

Effect of propylgallate on a dipalmitoylphosphatidylglycerol and calcium mixture.

Effect of propylgallate (PrG) on the thermotropic behavior of mixtures of dipalmitoylphosphatidylglycerol (DPPG) and Ca2+ was studied by means of differential scanning calorimetry (DSC). In the case of DPPG or DPPG/Ca (molar ratio, 15 : 1), the transition temperature (Tm) of the main transition and the subtransition decreased from 40 degrees C to 29 degrees C and from 29 degrees C to 20 degrees C, respectively, with an increase in the concentration of PrG. The addition of PrG to the DPPG/Ca mixture induced a shoulder on the high temperature side in the reheating scan. Neither PrG nor low concentrations of Ca2+ bind to the Lc phase of DPPG. When the molar ratio of DPPG to Ca was 1 : 1, the subtransition did not occur, that is, only the main transition (Tm = 90 degrees C) appeared. The Tm of the main transition was slightly affected by PrG. On the addition of PrG, another metastable endothermic transition peak (Tm = 78 degrees C) appeared. It is concluded that Ca2+ and PrG inhibit each other's binding.

Calcium↗
PubMed1989

Molecular cloning and nucleotide sequence of a cDNA encoding Euglena gracilis cytochrome c1.

The amino acid sequence of the mature protein of Euglena gracilis cytochrome c1 was determined by sequencing of its cDNA. A cDNA expression library was constructed from Euglena poly(A)+ RNA in phage lambda gt11 and screened with an antiserum raised against cytochrome c1 polypeptide isolated from purified E. gracilis complex III. An isolated cDNA clone consisted of 872 base pairs and encoded the mature protein with 243 amino acids. The deduced amino acid sequence contained the unusual heme binding sequence-Phe-Ala-Pro-Cys-His- (Mukai, K. et al. (1989) Eur. J. Biochem. 178, 649-656) instead of the typical sequence,-Cys-X-Y-Cys-His-, commonly found in C-type cytochromes. Comparison of the sequence with those of several other cytochromes c1 revealed that Euglena cytochrome c1 conserved the residues probably ligating heme-iron, those supposed to interact with cytochrome c and regions anchoring the mitochondrial inner membrane.

Amino Acid Sequence↗
PubMed1989

Leydig cell tumor of the ovary associated with endometrial carcinoma and containing 17 beta-hydroxysteroid dehydrogenase.

A case of ovarian Leydig cell tumor associated with adenocarcinoma of the endometrium in a 66-year-old woman is described herein, the eighth such case published. Clinically, both masculinizing and feminizing symptoms were observed: an increase in facial hair growth, slight baldness, clitoromegaly, and postmenopausal genital bleeding. Three biopsies of the endometrium during a 5-month preoperative period showed atypical hyperplasia. Surgically resected material contained a Leydig cell tumor of the left ovary and focal adenocarcinoma in atypical hyperplasia of the endometrium. Serum levels of androgens and estrogens measured by radioimmunoassay decreased after removal of the tumor. Immunohistochemical studies revealed that the Leydig cell tumor contained testosterone, estrogens, and 17 beta-hydroxysteroid dehydrogenase (HSD) in the cytoplasm. This is the first report of a Leydig cell tumor in which the localization of 17 beta-HSD was demonstrated immunohistochemically.

17-Hydroxysteroid Dehydrogenases↗
PubMed1989

Histochemical and immunohistochemical evidence of glandular differentiation in thymic carcinoma.

Eighteen cases of primary thymic carcinoma were reviewed from the viewpoint of glandular differentiation. Squamous differentiation was evident in 14 cases (83%). Immunohistochemical study revealed secretory component (SC)-positive carcinoma cells in 12 cases (67%), most of which were also associated with squamous differentiation. Three of these 12 cases contained areas with a definite glandular or microcystic structure with occasional epithelial mucin, and were diagnosed as adenosquamous carcinoma. Review of patients' medical records revealed that thymic carcinomas with a glandular element were more often resectable at surgery, and had a much better prognosis than those without a glandular element. However, further study on larger number of cases is necessary to confirm this relationship. Because SC-positive epithelial cells do exist in the non-neoplastic thymus, the presence of a glandular component suggests another direction of morphological and/or functional differentiation of thymic carcinoma cells in addition to the well-known squamous differentiation.

Biomarkers, Tumor↗
PubMed1989

Nuclear DNA content by cytofluorometry of stage I adenocarcinoma of the lung in relation to postoperative recurrence.

Forty-six cases of adenocarcinoma of the lung, categorized as stage I (T1N0M0, T2N0M0) pathologically, were studied in terms of nuclear DNA content (NDC) determined by cytofluorometry. They comprised 23 cases each with and without tumor recurrence within five years postoperatively, and the NDC was compared in 23 pairs in which the tumor size and the degree of histologic differentiation were completely matched. The NDC was larger in the recurrent group than in the nonrecurrent group in terms of mean nuclear DNA content (MNDC), DNA histogram pattern, and occurrence of the aneuploid stem cell line, of which the difference in MNDC was statistically significant (p less than 0.05). When the comparison of NDC was made between the nonrecurrent and recurrent groups in the well differentiated (W/D), moderately to poorly differentiated (M.P/D), T1, and T2 subgroups, the NDC of the recurrent group was significantly larger than that of the nonrecurrent group in the W/D (MNDC, p less than 0.01 and DNA histogram pattern, p less than 0.005) and T1 subgroups (MNDC, p less than 0.05), but not in the M.P/D and T2 subgroups. The results indicate that the NDC is a good predictor of prognosis in stage I adenocarcinoma of the lung and its prognostic importance increases in more differentiated and smaller tumors, compared to less differentiated and larger tumors.

Adenocarcinoma↗
PubMed1989

Lymphocyte subsets in pulmonary venous and arterial blood of lung cancer patients.

Lymphocyte subsets in pulmonary venous blood (PVB) smears from 42 patients with lung cancer were immunocytochemically determined. In four patients, pulmonary arterial blood (PAB) smears were also studied for comparison with PVB. Seven healthy donor peripheral blood (PB) smears were used as controls. The percentage of T cells, helper/inducer T (Th) cells and B cells were significantly lower (P less than 0.01) than in normal controls but those of suppressor/cytotoxic T (Ts) cells, natural killer (NK) cells (P less than 0.01) and S100+ small lymphoid cells (P less than 0.05) were higher. This resulted in a decrease in the Th:Ts value in cancer patients (1.46 vs. 2.28 for normal controls; P less than 0.01). The Th and Ts value of PVB from patients in pathological Stages III and IV was lower than from those in Stages I and II because of the increase in Ts cells in the former (P less than 0.05). S100+ small lymphoid cells were increased in cancer patients, especially in those with adenocarcinoma. The present study demonstrates immunoregulation abnormalities in cancer bearing hosts, the results correlating well with the stage of the cancer. Determining lymphocyte subset alterations in PVB did not, however, enable us to detect the changes associated with local immune responses against cancer.

Adult↗
PubMed1989

[Multifocal gliomas in cerebral hemisphere associated with von Recklinghausen's disease: case report].

A case of intracerebral multifocal gliomas with von Recklinghausen's disease is reported. A 12-year-old boy was admitted to our hospital with an episode of convulsive attacks which were uncontrolled by anticonvulsants. CT scan and MRI revealed small well circumscribed tumors in the left frontal cortex and left parietal subcortex. Both of the tumors revealed low density in plain CT scan and low intensity in T1 weighted MRI. The vascularity of these tumors was poor in cerebral angiography. In other words these tumors were of a similar nature. The histology of the frontal tumor, which was totally removed surgically, showed typical pilocytic astrocytoma. The other tumor in the left parietal subcortex must also be included in the category of low grade glioma. In the sixth month after the operation, we could find neither recurrence of the frontal glioma nor enlargement of the parietal tumor, on CT and MRI findings. Immunohistochemically, the outer portion of the Rosenthal fiber in this tumor was positive for GFAP and S-100 protein, but the inner portion was negative, because the GFAP and S-100 protein there had degenerated. The cytoplasm of this tumor's cell was abundant with mitochondria and Golgi's bodies compared to the fibrillary astrocytoma. This case may be the first case of multifocal gliomas in the same cerebral hemisphere. We suggest that multifocal gliomas grow naturally, and over the years, tumors combine with each other and finally constitute a large type diffuse glioma.

Astrocytoma↗
PubMed1989

Non-Hodgkin's lymphoma of the pleural cavity developing from long-standing pyothorax. Summary of clinical and pathological findings in thirty-seven cases.

Our previous study suggested a close relation between a preceding chronic tuberculous pyothorax and the development of non-Hodgkin's lymphoma (NHL) in the pleural cavity. To confirm this further, 37 cases were collected from Japanese hospitals, and their clinical and pathological findings summarized. The age at first admission for lymphoma of patients ranged from 46 to 81 (mean 63) years, the male to female ratio being 5.2:1. All patients were admitted after a 22-55 (mean 33) year history of pyothorax resulting from artificial pneumothorax for the treatment of pulmonary tuberculosis (29 cases) or tuberculous pleuritis (seven cases). The most common presenting symptom was chest pain. The main tumor mass, detected by chest roentgenogram and computed tomographic scans, was situated in the pleura (28 patients), the lung near the pleura (five patients) and the pleura and lung (four patients). The diagnosis of pleural NHL was made by biopsy for 31 of the patients and at autopsy for the other six. Histologically 30 (81%) of the 37 cases were of the diffuse large cell type, and of these the immunoblastic type was the most common (22 cases). Immunological and immunohistologic studies revealed a B-cell nature of the proliferating cells in all but one tumor. Thirty-two patients received chemotherapy and/or radiotherapy. Twenty-seven patients died between one and 144 (median eight) months of diagnosis. Autopsies carried out in 23 cases revealed the disease to have been localized to the thorax in 11 patients. These findings indicated that malignant B-cell lymphoma arose as a monoclonal growth from a pool of proliferating polyclonal B lymphocytes in tissues affected by the chronic tuberculous pyothorax.

Aged↗
PubMed1989

A rare case of asynchronous bilateral B-cell lymphoma of the breast.

We report an asynchronous bilateral malignant lymphoma of the breast, in a 56-year-old woman, presenting unusual clinical signs and histological features. The patient, who had a family history of breast cancer, had undergone a standard right radical mastectomy four years previously for a non-epithelial malignant tumor. At that time, the tumor was thought to be a stromal sarcoma, because some of the neoplastic cells were elongated or vacuolated. The patient recently became aware of a rapidly growing tumor of the left nipple without erosion or pain. This tumor underwent biopsy, and the histological examination showed a non-Hodgkin's lymphoma of diffuse mixed type. Staging procedures demonstrated no sign of generalized disease. Following a modified left radical mastectomy for optimal local control and accurate staging, adjuvant chemotherapy consisting of vincristine, cyclophosphamide, prednisolone and doxorubicin was initiated. Immunohistochemical staining for PAN-B and leucocyte common antigen revealed both tumors to be malignant lymphomas of B-cell type, and the first lymphoma of the right breast was thought to be showing 'signet ring' cell change. Since the two tumors were morphologically quite different from each other, it was suggested that they were asynchronous bilateral primary malignant lymphomas; however, the possibility remains that the recent left breast tumor is a recurrence of the malignant lymphoma of the right breast. The patient is currently disease-free, 10 months after surgery.

B-Lymphocytes↗
PubMed1989

[Left ventricular performance before and after left ventriculotomy and removal of a left ventricular aneurysm].

The effects of left ventriculotomy on left ventricular performance were studied in seven patients with ventricular tachyarrhythmia (VT) and nine patients with left ventricular aneurysm (LVA). Hemodynamic and left ventriculographic findings were evaluated before and after operations. In VT the non-contracting areas, measured at end-diastole, as mean 10.8 +/- 7.1% of the left ventricular internal surface area. There was no significant fall in left ventricular ejection fractions (EF), cardiac indexes (CI) and left ventricular end-diastolic volume indexes (LVEDVI) after left ventriculotomy. In LVA, the non-contracting areas decreased from 31.0 +/- 7.4% to 13.7 +/- 13.5% (p less than 0.01) in association with a reflex decrease in LVEDVI from 117 +/- 31.8 ml/m2 to 90.4 +/- 24.7 ml/m2 (p less than 0.05). EF increased from 40.8 +/- 7.00% to 54.6 +/- 10.7% (p less than 0.01). There was no significant change in CI and left ventricular stroke volume index after left ventricular aneurysmectomy. The observations indicate that left ventriculotomy of limited size is an acceptable and a safety approach to the ventricular tachyarrhythmias and another cardiac operations.

Adolescent↗