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Biomedical subjects

Y Urano

Publications and source records attributed to Y Urano.

At least 73 records · Page 4Linked to original sources
PubMed1993

Unusual substituent effects in the hydroxylation of phenols by a Cu(2+)-ascorbic acid-O2 system, gamma-radiolysis, and microsomes.

Aromatic ring hydroxylation of phenolic compounds proceeded selectively in a Cu(2+)-ascorbic acid-O2 system. In contrast to usual oxidation systems, unusual substituent effects were observed: electron-withdrawing groups accelerate and electron-donating groups retard the hydroxylation. Hydroxyl radicals generated by gamma-radiolysis also converted phenols into catechols and hydroquinones. The close resemblance of these two systems led us to presume that the active intermediate in the Cu(2+)-ascorbic acid-O2 system is hydroxyl radical or an equivalent species. The unusual substituent effects were also observed in the hydroxylation of p-substituted phenol by microsomes, a cytochrome P-450-dependent reaction. These results imply that the Cu(2+)-ascorbic acid-O2 system is an effective biomimetic oxidation system.

Animals↗
PubMed1993

Dispersed cell culture of human sweat duct cells under serum-free conditions.

Human eccrine gland duct cells were successfully cultured using a serum-free medium, K-GM medium. Eccrine sweat ducts were isolated from dispase treated skin specimens from palms or soles. After treatment of the isolated ducts with trypsin and EDTA, dispersed cells were cultured in K-GM medium. In primary cultures, small colonies were seen 3 to 4 days after inoculation. Then the cells rapidly proliferated and formed large colonies with a paving stone-like cell arrangement. During the culture, small dome shaped areas were sometimes formed in the centers of colonies. Cultures multiplied for a maximum of 7 passages. The plating efficiencies of the 1st to 6th passage cells were about 20% to 30%. Immunocytochemically, cultured cells were positively stained with anti-carcinoembryonic antigens, K8.37 and K8.13, but not with anti-S100 protein, anti-HLA-DR, 34 beta B4, or PKK3. An electron micrograph of the cultured cells showed a multilayer of flattened cells linked by desmosomes. These results indicate that the cultured cells possessed the staining properties compatible with those of the ductal portion of eccrine sweat glands. No contamination by other mesenchymal cells, such as fibroblasts, was seen during the culture.

Antigens↗
PubMed1993

Light microscopic autoradiographical analysis of [125I]epidermal growth factor binding in basal cell epithelioma and squamous cell carcinoma of the skin.

Levels of epidermal growth factor (EGF) receptor expression were investigated in five basal cell epitheliomas (BCEs) and 10 primary lesions from squamous cell carcinoma (SCC) of the skin, using light microscopic autoradiography with [125I]EGF. All of the BCEs were clinically the pigmented type and histologically the solid type. All of them showed an EGF binding level similar to that of the basal and suprabasal layers of the normal epidermis. The SCCs included one case of Bowen's disease (SCC in situ), five of the well differentiated type, three of the moderately differentiated type and one of the poorly differentiated type. Eight of the 10 SCCs showed an EGF binding level similar to that of the normal epidermal basal and suprabasal cell layers. One of the two remaining SCCs, a moderately differentiated type, showed highly increased EGF binding. The other one, a poorly differentiated type, showed very little EGF binding in a large region consisting of poorly differentiated cells, although a small area composed of more differentiated, nest-forming cells had an EGF binding level similar to that of the basal and suprabasal cells. Metastasis was found in three of these 10 SCCs after surgery. Two of the three SCCs with metastasis showed increased or decreased EGF binding levels in primary lesions as described above; in contrast, primary lesions of the seven SCCs without metastasis had EGF binding levels similar to those of the normal epidermal basal and suprabasal cells. Abnormally increased or decreased EGF binding level in SCC of the skin may be indicative of a poor prognosis, although it is necessary to examine more SCCs to confirm this assumption.

Aged↗
PubMed1992

Immunohistological analysis of P53 expression in human skin tumors.

The p53 expression in various skin tumors was immunohistologically evaluated using two mouse monoclonal anti-p53 antibodies, PAb421 and PAb1801. The p53 expression was not detected in the normal epidermal cells. Nuclear staining suggested that the p53 expression was observed in 10 of 26 squamous cell carcinomas (SCCs) from 24 patients, in one undifferentiated carcinoma, one proliferating trichilemmal cyst, one malignant proliferating trichilemmal tumor and in one metastatic carcinoma of breast cancer. None off four cases of Bowen's disease (SCC in situ) showed nuclear staining. In the SCCs, five of 20 primary lesions, three of four recurrent lesions and both of two metastatic lesions had positive nuclei. There was one case of SCC in which a primary lesion was negative but a recurrent lesion was positive. Thus, p53 expression was more frequently observed in SCCs at more clinically advanced stages. This may suggest that p53 has some relevance to progression of SCC. Nuclear staining was not detected in any of the following cases: two cases of seborrheic keratosis, one eccrine poroma, one keratoacanthoma, 11 basal cell epitheliomas, two mammary Paget's disease, three genital Paget's disease, one sebaceous carcinoma, four malignant melanomas, six lymphomas, two leukemia cutis and two angiosarcomas.

Antibodies, Monoclonal↗
PubMed1991

Interstitial chromosomal deletion within 4q11-q13 in a human hepatoma cell line.

Southern blot analysis revealed the presence of an aberrant albumin gene as well as a normal one in a human hepatoma cell line, HuH-7. A genomic sequence carrying this altered gene was isolated and characterized. This clone contains a 3-kbp 3' segment of the albumin gene linked to a non-albumin sequence at intron 11. The non-albumin sequence is assigned to chromosome 4q12-q13 by in situ hybridization. This indicates an interstitial deletion of a chromosomal segment within 4q11-q13 because the albumin gene is mapped there. The truncated albumin gene is detected in an early passage of HuH-7 cells and has been maintained stably in cell culture.

Albumins↗
PubMed1991

Culture of human outer root sheath cells from plucked hair follicles in serum-free conditions.

We succeeded in culturing human outer root sheath cells (ORSC) in serum-free conditions without a biological feeder layer. The combination of collagen type IV substrate and modified MCDB 153 medium supplemented with bovine pituitary gland extract (K-GM medium) could support the growth of ORSC. These cells can be serially cultivated for at least 4 passages and stored in liquid nitrogen with good recovery. Thus, a large series of experiments using ORSC may be run simultaneously.

Cell Division↗
PubMed1991

Detection of burst-promoting activity in spleens of myeloproliferative sarcoma virus-infected mice using serum-free cultures.

Myeloproliferative syndrome was induced in adult DBA/2 mice by inoculation with myeloproliferative sarcoma virus (MPSV) and Friend murine leukemia virus (F-MuLV) as a helper virus. On day 26 after infection, the spleen weighed a maximum of 2.0 g (about 30 times the control weight). Assay of multipotent stem cells in vitro showed that the more enlarged spleens contained an increased number and concentration of mixed colony-forming units (CFU-mix) (at maximum, 11 times higher than the control). When the supernatant of cultured spleen cells was added to a serum-free bone marrow cell culture with or without erythropoietin (Epo) for detection of burst-promoting activity (BPA), it enhanced erythroid mixed colony (E-mix) formation only in the presence of Epo (p less than 0.05). Even when addition of Epo was delayed, it still induced a significant number of E-mix (p less than 0.05). These findings rule out a mimic effect of Epo resembling BPA and indicate the presence of BPA in the spleen. The culture supernatant also supported the proliferation of interleukin 3 (IL-3)-dependent 32Dcl cells. Therefore, although purification of the BPA substance has not yet been accomplished, BPA in the supernatant seems to depend on the presence of IL-3, which is known to be one of the factors stimulating multipotent hemopoietic stem cells. The presence of BPA- or CFU-mix-stimulating activity in the spleen after infection might be responsible for the development of panmyelosis, which is a characteristic of MPSV-induced myeloproliferative syndrome.

Animals↗
PubMed1990

Sequential study on spontaneous colony formation by bone marrow cells during butylnitrosourea-induced leukemogenesis in the rat.

The spontaneous colony (SC)-forming activity of bone marrow cells of rats during butylnitrosourea (BNU) treatment was studied sequentially in an attempt to analyze stages of leukemogenesis. Aspirated bone marrow cells from female Sprague-Dawley (SD) rats that had been given continuous access to drinking water containing 400 ppm BNU were examined at intervals of 3-5 weeks for colony formation of granulomonocytic cells with or without supplemental colony-stimulating factor (CSF). Granulocytic leukemia was first observed at week 12, and the cumulative incidence reached 80% by week 30. SCs were obtained in 56% of rats in the early stage (3 weeks) and in up to 59% of rats in the late stages (20-25 weeks). However, in the middle stages colony formation was rare, even with the addition of CSF. When adherent cells were removed from the bone marrow cells, the SC-forming activity in the early stage was almost entirely lost, whereas much of that in the late stage remained. It is possible that in the former case, overproduction of endogenous CSF by adherent cells under the influence of BNU treatment could be involved. In contrast, late stage SC formation may be associated with the generation of altered cells, including leukemic or preleukemic elements, which have increased capacity for autonomous growth. The loss of SC-forming activity in the middle stage appeared to be attributable to an extreme reduction in endogenous CSF due to marked devastation of the bone marrow. Technical improvement in adjusting more precisely the level of CSF in the culture medium is required to enable further analysis of leukemogenesis, focused on the colony-forming activity of target cells.

Animals↗
PubMed1990

Immunohistochemical demonstration of peptidylarginine deiminase in human sweat glands.

Human skin is known to contain protein-bound citrulline. This is the product of enzymatic deimination of arginine residues catalyzed by peptidylarginine deiminase. We probed frozen sections of human skin with a rabbit antiserum raised to rat skeletal muscle peptidylarginine deiminase using the avidin-biotin-peroxidase complex technique. This led us to interesting findings. No staining was observed in epidermis, inner root sheaths of hair follicles, sebaceous glands, and hair erector muscle. However, we noticed specific staining of the cytoplasm of secretory and myoepithelial cells of both eccrine and apocrine sweat glands. The procedure also stained neoplastic cells present in specimens dissected from extramammary Paget's disease. The data mean that peptidylarginine deiminase may be used as a new marker in the classification of skin neoplasms showing sweat gland differentiation. Possible localization of multiple types of peptidylarginine deiminases in human skin is discussed.

Antigens, Differentiation↗
PubMed1990

Eosinophilic polymyositis induced by tranilast.

A 38-year-old man with asthma developed eosinophilic polymyositis following the administration of Tranilast, an antiasthmatic agent. Low grade fever, erythematous rashes on the entire body, dysphagia, blood eosinophilia, elevations of serum creatine phosphokinase and myoglobin levels, and inverted T waves in the electrocardiogram were noted. A muscle biopsy showed focal degeneration of muscle fibers with an infiltrate of eosinophils and lymphocytes. A rechallenge with Tranilast resulted in erythema formation, blood eosinophilia, and elevations of some serum muscle enzymes and myoglobin levels. Tranilast was considered to be the causative agent. This is the first reported case of Tranilast-induced eosinophilic polymyositis.

Asthma↗
PubMed1990

Co-culture of human hair follicles and dermal papillae in a collagen matrix.

Human hair follicles, either alone or in combination with dermal papillae, were cultured in a collagen matrix. When plucked hair follicles were cultured alone, spike-like structures composed of outer root sheath cells started growing around the follicle and then radiated into the gel. When isolated dermal papillae were embedded close to the follicles, spikes started growing earlier and grew more rapidly than without the papillae. In cultures of excised follicles from which the dermal papilla had been removed, epithelial cells (possibly hair bulb cells) started growing out from the bulbous portion and then also formed spikes. In the presence of a papilla, the spikes elongated toward the papilla, finally reaching and surrounding it. These findings suggest that dermal papilla cells produce a factor(s) that enhances growth of follicular epithelial cells and also attracts those cells. In cultures of whole excised follicles, two major characteristic patterns of cellular growth were recognized. When the dermal papilla remained inside the bulb in contact with the hair bulb matrix, the hair matrix cells proliferated and differentiated in the normal manner, resulting in elongation of the hair shaft and follicle. But when the papilla was detached from the hair bulb matrix, epithelial cells proliferated from the bulbous portion and finally formed hair follicle-like structures. Thus, attachment of the dermal papilla to the hair bulb matrix in the bulbous portion appears to be necessary for growth of the hair and follicle in the normal manner. Our model may be useful for examining the interaction between follicular epithelial cells and dermal papillae and for studying the growth of hair and follicles in vitro.

Adult↗
PubMed1989

Arteriovenous malformation of the spinal cord. Three-dimensional reconstruction of the intramedullary abnormal vessels.

We report a case of spinal arteriovenous malformation (AVM) in which detailed morphological examination of the intramedullary vascular lesion was carried out employing serial section studies. The relationship of the malformation to parenchymal lesions was evaluated. An abnormal vessel at the spinomedullary transition, whose lamina elastica was partially interrupted, was suggestive of a shunt vessel. The location of the intramedullary abnormal vessels and foci of softening of the spinal cord almost overlapped in distribution. Three-dimensional reconstruction of the intramedullary abnormal vessels demonstrated marked elongation and tortuosity of the original vascular architecture and they ended in the extramedullary abnormal vessels with thickened wall. Thus, our study showed that the intramedullary abnormal vessels were the result of secondary changes subsequent to pressure and volume overload inflicted upon the spinal venous system through AVM. Compression by tortuous elongation of the intramedullary vessels is the apparent cause of the parenchymal softening. A traumatic factor in the aetiology of the AVM was also discussed, since the patient had had two preceding episodes of traffic accidents with cranial and lumbar injury. Trauma seemed to be significant factor as a trigger of symptoms.

Aged↗
PubMed1989

Decreased high-affinity epidermal growth factor receptors in psoriatic epidermis.

Using 125I-EGF the distribution of EGF receptors in psoriatic epidermis was autoradiographically examined. Binding sites of 125I-EGF (20 ng/ml) were mainly located at basal and suprabasal cells in normal and uninvolved psoriatic epidermis, whereas they were located at spinous cells as well as at basal and suprabasal cells in affected psoriatic epidermis. Binding of 125I-EGF (1 ng/ml), on the other hand, was observed in normal and uninvolved psoriatic epidermis but not in affected psoriatic epidermis. The majority of EGF receptors in affected psoriatic epidermis were featured by low affinity for EGF.

Autoradiography↗
PubMed1989

An autopsy study of lung cancer with special reference to the relationship between cigarette smoking and histological differentiation of adenocarcinoma and squamous cell carcinoma.

To clarify the relationship between cigarette smoking and the degree of differentiation of adenocarcinoma and squamous cell carcinoma of the lung, 207 male and 103 female cases of adenocarcinoma and 125 male and 26 female cases of squamous cell carcinoma, autopsied between 1958 and 1985, were reviewed. In males, adenocarcinoma cases increased as the degree of differentiation decreased. In females, poorly differentiated cases of adenocarcinoma and, in males, those of squamous cell carcinoma, were minimal, and the number of poorly-differentiated adenocarcinoma cases significantly less (p less than 0.005) in females than in males. The number of male smokers with adenocarcinoma increased, and that of female non-smokers decreased, as the degree of differentiation decreased. On the other hand, the number of male smokers with squamous cell carcinoma decreased and that of female non-smokers increased as the degree of differentiation decreased. The incidences of well-differentiated adenocarcinoma in female non-smokers, well-differentiated squamous cell carcinoma in male heavy smokers and poorly-differentiated squamous cell carcinoma in female non-smokers were prominent. A histopathological diagnoses of differentiated subtypes of adenocarcinoma and squamous cell carcinoma of the lung is useful and important in understanding the biological characteristics of lung cancer and also the effects of cigarette smoking.

Adenocarcinoma↗
PubMed1989

An autopsy case of myelodysplastic syndrome (MDS): diagnostic problems between MDS and the other haematopoietic disorders including acute myelofibrosis.

We report an autopsy case of myelodysplastic syndrome (MDS) in a 35-year-old male, who presented with pancytopenia and bleedings. Bone marrow specimens disclosed myelofibrosis and hypercellular marrow with more than 60% atypical erythroblasts in the bone marrow cells. Type I or type II blasts were less than 10% of the peripheral blood and bone marrow cells during the clinical course. At autopsy, infiltration by myeloid and erythroid cells and megakaryocytes was noted in the liver, spleen and lymph nodes. According to the FAB classification, this case might be classified into refractory anemia with excess of blasts (RAEB) or RAEB in transformation. However, the remarkable neoplastic proliferation of three haematopoietic cell lines also indicates acute myeloproliferative disorder such as acute myelofibrosis or acute panmyelosis.

Acute Disease↗