Biomedical subjects

E Kudo

Publications and source records attributed to E Kudo.

At least 19 recordsLinked to original sources

PubMed1996

Detection of herpes simplex virus DNA in tear fluid of stromal herpetic keratitis patients by nested polymerase chain reaction.

The value of the polymerase chain reaction (PCR) in the diagnosis of stromal herpetic keratitis was examined using tear fluid specimens; the sensitivity of the nested PCR method in detecting the herpes simplex virus (HSV) genome was 1 plaque-forming unit/mL. PCR assay of 72 tear samples from the eyes of 15 patients with stromal herpetic keratitis detected the HSV genome in 5 (33.3%). No positive band was detected in 20 tear samples from both eyes of 10 healthy volunteers. Seven of 38 tear samples (18.4%) and 1 of 34 samples (2.9%) collected from the diseased eye and the contralateral normal eye, respectively, produced positive results; the difference in rates was statistically significant (P < 0.05). The positive rate of samples collected from the diseased eye during an active phase was 16.0% (4 of 25 samples); in the quiescent phase, 23.1% (3 of 13 samples); the difference was not significant (P = 0.45). In HSV genome-positive cases, the average number of tear collections needed to detect the HSV genome was 3.3. Results indicate that PCR assay of tear fluid provides valuable information for the diagnosis of stromal herpetic keratitis, and that repeated tear samples should be collected regardless of the phase of the phase of disease activity.

Administration, Topical↗

PubMed1995

[Determinants of task preferences when performance is indicative of individual characteristics: self-assessment motivation and self-verification motivation].

The present study was conducted to examine determinants of information-gathering behavior with regard to one's own characteristics. Four tasks with different self-congruent and incongruent diagnosticity were presented to subjects. As self-assessment theory predicted, high diagnostic tasks were preferred to low tasks. And as self-verification theory predicted, self-congruent diagnosticity had a stronger effect on task preference than self-incongruent diagnosticity. In addition, subjects who perceived the relevant characteristics important inclined to choose self-assessment behavior more than who did not. Also, subjects who were certain of their self-concept inclined to choose self-verification behavior more than who were not. These results suggest that both self-assessment and self-verification motivations play important roles in information-gathering behavior regarding one's characteristics, and strength of the motivations is determined by the importance of relevant characteristics or the certainty of self-concept.

Adult↗

PubMed1994

Transgenic expression of IL-10 in pancreatic islet A cells accelerates autoimmune insulitis and diabetes in non-obese diabetic mice.

To study the paracrine effect of IL-10 on autoimmune insulitis and diabetes, we produced IL-10 transgenic non-obese diabetic (NOD) mice (NOD-IL-10) in which murine IL-10 was expressed in pancreatic islet A cells under the control of a rat glucagon promoter without directly manipulating pancreatic islet B cells. Among 11 founder mice, four of four males and three of seven females developed diabetes by 10 weeks of age. Histological analysis of six NOD-IL-10 revealed severe insulitis and prominent ductal proliferation. NOD-IL-10 also showed spotty lymphocytic infiltration in the lung and liver in four of six founder mice. The onset of diabetes in NOD-IL-10 was remarkably earlier than that of 14 weeks of age at the earliest in female non-transgenic NOD mice. When the NOD-IL-10 mouse was backcrossed to C57BL/6 mice, none of the resulting F1, B-N2 or B-N3 generation toward C57BL/6 mice showed diabetes even at 39 weeks of age, in spite of the presence of peri-insulitis and prominent ductal proliferation, while two of four mice of the N-N2 generation toward NOD mice showed early-onset diabetes. Thus, transgenic paracrine expression of IL-10 in situ in the NOD genetic background enhances autoimmune insulitis and diabetes in their onset and severity, ignoring gender difference. Because expression of IL-10 was detected by polymerase chain reaction in pancreatic islets of non-transgenic NOD mice after 5 weeks of age, IL-10 secreted in situ is regarded to enhance cell-mediated autoimmune diabetes, in spite of established in vitro anti-Th1 activity of IL-10.

Animals↗

PubMed1994

Multiple fluorescence-based PCR-SSCP analysis.

Multiple fluorescence-based polymerase chain reaction single-strand conformation polymorphism (MF-PCR-SSCP) was developed. The target sequence was amplified by PCR using forward and reverse primers labeled with two different fluorescent dyes at their 5' ends. The amplified products were then heat-denatured, mixed with internal standard DNA markers labeled with a third fluorescent dye and applied to a temperature-controlled gel in an automated DNA sequencer, with a gel-temperature-controlling system. Mutations were detected as positional shifts of two-colored peaks in the electrophoretogram. The image data were analyzed by the computer program GENESCAN 672. The peak positions were standardized to internal DNA size markers. MF-PCR-SSCP analysis of 7 human tumor cell lines with 7 different single base mutations of the human K-ras oncogene detected all mutations even under the same electrophoresis conditions. Complete loss of heterozygosity was detected in two cell lines simultaneously. A gel temperature at 20 degrees C and polyacrylamide concentration of 10% gave the best separation. MF-PCR-SSCP is superior to the current PCR-SSCP in several ways: it does not involve radioactivity, migration patterns are standardized to internal standard DNA markers, there is a strict temperature-controlling system and the higher percentage of the gel enables better separation with resultant 100% detection of mutations most likely under one set of electrophoresis conditions.

Base Sequence↗

PubMed1993

Molecular cloning of human amidophosphoribosyltransferase.

The cDNA of human amidophosphoribosyltransferase (EC 2.4.2.14, ATase), which is the supposed regulatory allosteric enzyme of de novo purine nucleotide biosynthesis, has been cloned from human hepatoma (HepG2) cDNA library. The predicted open reading frame encodes a protein of 517 amino acids with a deduced molecular weight (Mr) of 57,398, which is consistent with the molecular mass of 56 kDa on SDS-polyacrylamide gel electrophoresis (SDS-PAGE) of the ATase subunit purified from human placenta. The derived amino acid sequence exhibits 93, 82, 41, 37, and 33% identity with the sequences of rat, chicken, Bacillus subtilis, Escherichia coli, and Saccharomyces cerevisiae ATases, respectively. Southern blot analysis suggested that the ATase gene exists as multiple copies. ATase mRNA (3.5 kb) is ubiquitously expressed in various human tissues. Comparison with rat and chicken ATases showed that two cysteine residues for an iron-sulfur cluster were conserved. Four consensus phosphorylation sites for cAMP-dependent protein kinase were found.

Amidophosphoribosyltransferase↗

PubMed1993

Development of T cells in SCID mice grafted with fetal thymus from AKR mice or F344 rats.

To examine the development of T cells within an allogeneic or xenogeneic environment, we engrafted the fetal thymus from AKR mice or F344 rats under the kidney capsule of SCID mice (mTG and rTG mice). T lymphopoiesis developed in SCID mice 2 months after transplantation, although the ratio of CD4/CD8 in both experimental groups was different from that of normal control. T cells in mTG mice did not show in vitro proliferation or cytotoxicity against either host-type C.B-17 (H-2d) or donor-type AKR (H-2k) cells, while they exerted potent activities against third-party B10 (H-2b) cells. In contrast, T cells in rTG mice exhibited proliferation against both host-type C.B-17 and donor-type F344 rat cells. Consistently, graft-vs.-host disease symptoms developed in these mice and histological examination showed impressive infiltration of lymphocytes into the skin or into the mucosal layers of the stomach. Activated state of T cells in rTG mice was also evidence by the positive expression of interleukin-2 receptor. Taken together, fetal thymus appears to contain progenitor cells which are sufficient for in vivo reconstitution of T lymphopoiesis, but species-specific environment is important for the induction of tolerance. In mTG mice, V beta 6+ T cells reactive to donor Mlsa determinants and V beta 3+ T cells reactive to host Mlsc determinants were deleted, suggesting that tolerance was regulated mainly by clonal deletion. By contrast, V beta 11+ T cells reactive to Mlsf determinants were not deleted possibly due to the lack of their ligands.

Animals↗

PubMed1992

Malignant peripheral nerve sheath tumors: an immunohistochemical study in relation to ultrastructural features.

The constituent cells in malignant peripheral nerve sheath tumors were examined by studying the expression of immunohistochemical markers for Schwann cells and perineurial cells in relation to ultrastructural features in 12 malignant peripheral nerve sheath tumors. Ultrastructural studies demonstrated mixed proliferation of Schwann cells, perineurial cells, fibroblastic cells, and primitive cells in many malignant peripheral nerve sheath tumors. Expression of S-100 protein was well correlated with Schwann cell-like differentiation of tumor cells. However, Leu-7 and epithelial membrane antigen, which have been considered to be specific to Schwann cells and perineurial cells, respectively, were common to Schwann cells, perineurial cells, and primitive cells. The common immunophenotypic expression suggests a close relationship among these cell types. The unusual expression of cytokeratin could be explained by the plasticity of intermediate filament expression.

Adult↗

PubMed1992

Epitopic heterogeneity of the CD36 antigen expressed by normal and neoplastic endothelial cells. An immunohistochemical study with a novel monoclonal antibody 8C9.

Phenotypic and functional heterogeneity of endothelial cells (ECs) is being recognized with increasing frequency. Here we report a novel murine monoclonal antibody (MoAb), named 8C9, that detects a unique epitope on the leukocyte differentiation antigen CD36 (platelet glycoprotein IV or IIIb) expressed by both normal and neoplastic ECs. In immunohistochemical and flow-cytometric studies, 8C9-immunoreactivity was detected on capillary ECs, adipocytes, monocytes, platelets and a human monocytoid cell line U-937, which are known to express the CD36 antigen. Blocking experiments using U-937 cells and studies on cryostat sections revealed that a murine MoAb OKM5, which detects the CD36 antigen, blocked the binding of 8C9 to its antigen. Immunoblot analysis showed that 8C9 bound to a 97-kDa membrane protein expressed by U-937 cells treated with phorbol ester. These results indicate that 8C9 detects the CD36 antigen. However, the findings that some OKM5-positive normal ECs in the liver, spleen and lymph nodes as well as neoplastic ECs in a cutaneous angiosarcoma did not react with 8C9, together with the fact that the CD36 antigen does not form a complex or associate with other proteins, suggest epitopic heterogeneity of the CD36 antigen expressed by these tissues.

Antibodies, Monoclonal↗

PubMed1991

Immunophenotypic heterogeneity in osteosarcomas.

Eighteen osteosarcomas were studied immunohistochemically. The tumors were classified into the following six histologic subtypes: five osteoblastic, four chondroblastic, four malignant fibrous histiocytoma-like, two telangiectatic, two low-grade central, and one giant cell-rich. Variable amounts of osteocalcin immunoreactivity were found in all tumors. Factor XIIIa-positive cells, which may be of fibrohistiocytic lineage, were present in three tumors of the malignant fibrous histiocytoma-like type, one of the telangiectatic type, one of the low-grade central type, and the tumor of the giant cell-rich type. One tumor of the osteoblastic type showed cytokeratin and epithelial membrane antigen immunoreactivities. The positive reactions for desmin in four tumors, for alpha-smooth muscle actin in 11 tumors, and for type IV collagen in one tumor seemed to indicate myofibroblastic differentiation of some tumor cells. S-100 protein-positive tumor cells were detected not only in all four tumors of the chondroblastic type, but also in three of the osteoblastic type, one of the low-grade central type, and in the tumor of the giant cell-rich type. These immunohistochemical results suggest that osteosarcomas are composed of heterogeneous cell populations, such as those of the osteoblastic, chondroblastic, myofibroblastic, and fibrohistiocytic types, and occasionally also of cells with epithelial features.

Adolescent↗

PubMed1991

Undifferentiated carcinoma of the vulva mimicking epithelioid sarcoma.

We report an undifferentiated sweat gland carcinoma of the vulva in an 80-year-old woman. The tumor, which was located in the right labium majus, resembled an epithelioid sarcoma histologically; it had a granulomatous appearance with multiple tumor nodules containing epithelioid tumor cells. The tumor also contained rhabdoid cells; a large cluster of them showed histological features indistinguishable from those of a malignant rhabdoid tumor. Immunohistochemically, the tumor cells reacted not only for epithelial markers such as cytokeratins, EMA, and CEA, which are known to be expressed by epithelioid sarcoma, but also for CA125 and with monoclonal antibodies recognizing sweat gland structures--namely, EKH5 and EKH6. For comparison, two epithelioid sarcomas and two extrarenal malignant rhabdoid tumors were also studied. Of these tumors, only one extrarenal rhabdoid tumor reacted with EKH5, and none reacted for CA125. Electron-microscopic examination of the present tumor showed the presence of discontinuous basal laminae and tonofibril-like structures as well as primitive cell junctions and interdigitating filopodia. From these findings, we conclude that the tumor was an undifferentiated sweat gland carcinoma mimicking an epithelioid sarcoma. Findings in this case support the idea of the diverse histogenesis of extrarenal malignant rhabdoid tumors and indicate that electron microscopy is important for differentiating epithelioid sarcoma from skin adnexal carcinoma.

Aged↗

PubMed1991

Atypical primitive neuroectodermal tumors. Comparative light and electron microscopic and immunohistochemical studies on peripheral neuroepitheliomas and Ewing's sarcomas.

Recently, primitive neuroectodermal tumors (PNETs) have been shown to cover a wide spectrum of small round cell sarcomas, probably including some Ewing's sarcomas (ESs) and extraskeletal Ewing's sarcomas (EESs), in addition to classical peripheral neuroepitheliomas (PNs). In studies of small cell sarcomas, we found a group of undifferentiated tumors resembling PNETs with some features of neuroectodermal differentiation, but possessing areas of relatively large, pleomorphic cells. To clarify the nature of these tumors and their relationship to PNETs, we examined the variety of histological, immunohistochemical and ultrastructural features of 11 small cell sarcomas. Five of these tumors were composed of uniform, small round cells and were classified as PNs because of the presence of definite Homer-Wright rosettes and fibrillary processes. The presence of well developed neurite-like processes containing neurosecretory granules and immunoreactivities for various neural markers suggested that these PNs showed more advanced neuronal differentiation. Two tumors, with the classical features of ES, showed no ultrastructural evidence of neuronal differentiation, although only gamma-gamma neuron-specific enolase (NSE) positivity was detected. Four undifferentiated tumors with atypical features, included in this study as an atypical PNET group, showed certain neuroectodermal characteristics, such as ganglion cell differentiation, perivascular pseudorosettes, and gamma-gamma NSE reactivity. It is concluded from this study that PNETs may include small round cell tumors showing different degrees of neuro-ectodermal differentiation and some histological variations.

Adolescent↗

PubMed1990

Cytoskeletal characteristics of myofibroblasts in benign neoplastic and reactive fibroblastic lesions.

The characteristics of the cytoskeleton of myofibroblasts were examined immunohistochemically in 10 extra-abdominal desmoid tumours, 3 palmar and 2 plantar fibromatoses and 5 nodular fasciitis; in the cultured cells of one desmoid tumour, and also ultrastructurally in 3 desmoid tumours. Polyclonal anti-desmin antibody reacted with the cells in 7 extra-abdominal desmoid tumours, 1 palmar fibromatosis, 1 plantar fibromatosis and 3 nodular fasciitis. Monoclonal antidesmin antibody reacted with cells in only 2 desmoid tumours. Desmin-positive spindle cells were scattered throughout these lesions. There were no marked ultrastructural differences between desmin-positive and desmin-negative desmoids. All specimens except one specimen of nodular fasciitis showed immunoreactivity for alpha-smooth muscle actin and vimentin. Muscle actin-positive cells were observed in all specimens. Cultured cells gave positive reactions with polyclonal desmin antibody as well as to vimentin antibodies and two preparations of actin antibodies, whereas the original tumour did not react with desmin antibody. The present studies suggested that the cytoskeleton of some myofibroblasts in both neoplastic and reactive lesions resembles that of smooth muscle cells.

Actins↗

PubMed1990

Cytoskeletal properties of alveolar soft part sarcoma.

The immunohistochemical expression of cytoskeletal proteins in alveolar soft part sarcoma (ASPS) was studied by light and electron microscopy. Of the five cases examined by the avidinbiotin-peroxidase complex method, variable numbers of immunoreactive cells for desmin were found in three, for vimentin in two, for muscle-specific actins in three, and for alpha-smooth muscle actin in four. Immunoelectron microscopic study demonstrated that desmin and vimentin were localized on whorled bundles of intermediate filaments in the perinuclear cytoplasm. In addition, a few dispersed intermediate filaments became evident in specimens treated with saponin and fixed with tannic acid. These immunohistochemical results indicate that a few tumor cells of ASPS may express some properties of the cytoskeleton of smooth muscle cells in addition to those of skeletal muscle cells. Considering the discrepancies reported in the actin isoforms demonstrated in myogenic tumors, we conclude that ASPS is probably a peculiar, primitive myogenic tumor that does not show any distinctive features of rhabdomyogenic or leiomyogenic differentiation.

Actins↗

PubMed1990

Giant cell fibroblastoma. A case report.

A case of giant cell fibroblastoma occurring in the knee of a 16-month-old girl is reported. The ill-defined subcutaneous tumor measuring 2 x 2 cm was composed of diffusely proliferating spindle-shaped tumor cells with scattered, atypical multinucleated giant cells in a myxoid or collagenous background and irregularly branching sinusoid-like tissue spaces. In addition to floret-type giant cells, a few osteoclast-like giant cells were present in a cellular area where tumor cells were focally arranged in a storiform pattern. Immunohistochemically, the tumor cells gave positive reactions for only vimentin and actin. In spite of the high recurrence rate of this type of tumor, the course of the patient after excision of the tumor has been uneventful. It is important to distinguish this rare, peculiar fibrous tumor from other soft tissue tumors including some sarcomas.

Female↗

PubMed1989

Expression of intermediate filaments in malignant fibrous histiocytomas.

The expression of intermediate filaments (IFs) in 34 malignant fibrous histiocytomas (MFHs) was studied immunohistochemically and ultrastructurally. Using the avidin-biotin-peroxidase method, positive reactions were detected as follows: for desmin in 12 tumors, for neurofilament in two tumors, for cytokeratin in one tumor, and for vimentin in 30 tumors. Desmin immunoreactivity was found in tumors of all four histologic subtypes and cytokeratin immunoreactivity was found in one tumor of the myxoid type. Because of the cross-reactivity of anti-neurofilament antibody with reactive histiocytes, the immunoreactivity for neurofilament seemed to be non-specific. Ultrastructurally, five of 13 tumors studied contained some tumor cells showing myofibroblastic or smooth muscle cell differentiation. A few tumor cells in one cytokeratin-positive tumor had tonofilaments in their cytoplasm. Desmin expression in some MFHs seemed to be due to myofibroblastic or smooth muscle cell differentiation of some tumor cells. Cytokeratin expression seemed to indicate epithelial differentiation in some MFHs. This varied expression of IFs in MFHs may reflect the heterogeneous nature of MFHs, and suggests that MFHs represent the final stages of dedifferentiation of several different types of sarcomas or, alternatively, represent forms of poorly differentiated sarcoma with the potential of developing into more differentiated sarcomas of heterogeneous origin.

Actins↗

PubMed1989

Malignant peripheral nerve sheath tumor (MPNST) showing perineurial cell differentiation.

We report a malignant peripheral nerve sheath tumor (MPNST) showing the unusual immunohistochemical feature of epithelial membrane antigen (EMA) immunoreactivity in a 52-year-old man. The tumor, located in the left paravertebral muscles, was composed of both cellular and myxoid areas. Spindle-shaped tumor cells were arranged in longitudinal cell cords, in a storiform pattern, and in whorled structures. Ultrastructurally, the tumor cells had many interdigitating cell processes, primitive cell junctions, and discontinuous external laminae. These histological and ultrastructural features were most consistent with those of an MPNST; but on immunohistochemistry, the tumor cells reacted for epithelial membrane antigen rather than for S-100 protein or Leu-7. Because EMA-immunoreactivity was recently demonstrated in perineurial cells, we concluded that the tumor was an MPNST mainly composed of tumor cells showing perineurial cell differentiation.

Cell Differentiation↗

PubMed1989

Clear cell sarcoma. An immunohistochemical and ultrastructural study.

The histogenesis of clear cell sarcoma was investigated by immunohistochemical examination of five tumors (two melanotic and three amelanotic) and electron microscopic examination of two of these tumors (one melanotic and one amelanotic). Melanin production was observed histologically in two of the tumors. The cytoplasm of cells in both types of tumor contained various numbers of melanosomes. Melanoma-specific antibody (HMB-45), anti-S-100 protein, and anti-vimentin antibodies gave positive reactions in four tumors, while all tumors showed Leu-7 immunoreactivity. No cytokeratin or epithelial membrane antigen (EMA) was detected immunohistochemically in any tumor. The immunoreactivity of this type of tumor with HMB-45 antibody strongly suggests melanocytic differentiation rather than schwannian or synovial differentiation. The reaction of the cells of one tumor with only Leu-7 indicates the existence of undifferentiated clear cell sarcoma of neuroectodermal origin that does not show definite melanocytic differentiation.

Adult↗

PubMed1989

Epithelial differentiation in synovial sarcoma. Correlation with histology and immunophenotypic expression.

The epithelial properties of the cells in six cases of synovial sarcoma, five biphasic and one monophasic, were examined. Epithelial cells formed well demarcated glandular nests with a multi- or single-layered lining, poorly defined nest-like clusters, or appeared as scattered single plump cells in a spindle-cell stroma. Keratinization was seen in multi-layered epithelia, and was suggested in single-layered epithelia from the presence of some enlarged eosinophilic cells. Immunohistochemically, epithelia lining glands showed reactivity for both low- and high-molecular-weight (MW) cytokeratins, and the reactions for both were strongest in keratinized cells. Clustered or single plump cells showed low-MW cytokeratin reactivity. All epithelial cells were negative for the largest cytokeratin (no. 1), and occasionally stained positively for vimentin. Spindle-shaped stromal cells usually stained positively for vimentin only. Type IV collagen was distributed linearly around well circumscribed epithelia, but not around poorly defined epithelia or plump cells. Epithelial membrane antigen was distributed linearly along glandular spaces and irregularly or granularly in clustered plump cells. The immunophenotypic epithelialization in synovial sarcoma was restricted, but showed considerable correlation with the histological grade of differentiation.

Adult↗