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Biomedical subjects

E Ichikawa

Publications and source records attributed to E Ichikawa.

At least 37 records · Page 2Linked to original sources
PubMed1995

Changes in cytokeratin expression in epidermal keratinocytes during wound healing.

In order to investigate the re-epithelialization process during wound healing, the hair on the back of guinea pigs was shaved and then excisional wounds were made through the entire thickness of the skin. Histological changes were observed and changes in the expression of different cytokeratin polypeptides were examined using an immunohistochemical technique. Immunohistochemical study revealed that the proliferating and migrating keratinocytes expressed the same cytokeratins as the basal cells of normal epidermis. In addition, the entire epidermis of fairly remote areas from the edges of the wound where no thickening was observed showed a temporarily abnormal staining pattern. The suprabasal cells in the regenerating epidermis temporarily expressed cytokeratins not only specific for suprabasal cells but also specific for basal cells. The cytokeratins expressed in normal basal keratinocytes were also present in the thickened granular layers. These data indicate that the expression of cytokeratins in the epidermal keratinocytes (even in fairly remote areas from the wound edges) changes during wound healing, that the origin of the migrating keratinocytes from the remaining epidermis seems to be the basal cells in the epidermis, and that the appearance of keratohyalin granules is not related to changes in cytokeratin expression.

Animals↗
PubMed1995

Immunohistochemical localization of keratins and involucrin in solar keratosis and Bowen's disease.

The present study was conducted to determine the patterns of immunohistochemical characterization of keratin (K) and involucrin in solar keratosis and Bowen's disease in order to clarify the abnormal differentiation or maturation of the tumor cells in these precancerous epithelial dermatoses. Seventeen human anti-cytokeratin antibodies and an anti-involucrin antibody were used to examine 15 cases of solar keratosis and 18 cases of Bowen's disease. Formalin-fixed and paraffin-embedded sections were stained with these antibodies by the avidin-biotin-peroxidase technique. In solar keratosis, keratin and involucrin distribution was similar to that in normal epidermis, whereas in Bowen's disease the keratin distribution varied among individual cases. The dyskeratotic cells in Bowen's disease showed a reduction or loss of staining with these antibodies, and they were occasionally positive for keratin 19. These observations suggest that there is a difference in keratin and involucrin expression between solar keratosis and Bowen's disease and that the atypical cells of Bowen's disease exhibit a diversity of differentiation.

Aged↗
PubMed1995

Changes of cytokeratin and involucrin expression in squamous cell carcinomas of the skin during progression to malignancy.

The detection of cytokeratins in neoplastic tissues by immunohistochemical methods has numerous diagnostic and investigative applications, because cytokeratins are usually conserved in tumour cells during malignant transformation. Recently, however, it has been reported that progression to malignancy is associated with commencement of expression of low-molecular-weight cytokeratins. In the present study, 42 specimens from 35 cases of squamous cell carcinoma (SCC) of the skin were analysed by immunohistochemical techniques, using polyclonal anti-involucrin antibody and a panel of monoclonal antikeratin antibodies, in order to investigate the nature and differentiation of SCCs. The expression of cytokeratins and involucrin in well-differentiated SCCs was similar to that in normal epidermis. In contrast with well-differentiated SCCs, the expression of differentiation-specific cytokeratins and involucrin was diminished in the immature tumour cells in proportion to the malignancy of the SCCs. Some antibodies, however, stained all tumour cells, irrespective of the degree of malignancy. Furthermore, expression of simple epithelial and non-cornifying stratified squamous epithelial cytokeratins was observed in atypical tumour cells of poorly differentiated SCCs. It is of interest that similar expression was noted in many tumour cells in the lymph node metastases and in some tumour cells in the primary cutaneous lesions. Cytokeratin expression similar to that in normal epidermal keratinocytes was conserved in well-differentiated SCCs, but the expression of cytokeratins changed during progression to malignant transformation. The expression of simple epithelial or non-cornifying stratified squamous epithelial cytokeratins in cutaneous SCCs may be a marker for their capability of invasion and metastatic potential.

Antibody Specificity↗
PubMed1995

The G1/S boundary-specific enhancer of the rat cdc2 promoter.

Multiple species of G1 cyclins and cyclin-dependent kinases are induced sequentially during G1 phase, and the expression of cyclin A and cdc2 genes is subsequently induced at the G1/S boundary. To analyze the mechanism of cdc2 promoter activation, the 5'-flanking region of the rat cdc2 gene was isolated and its structural features were characterized. The highly conserved sequence between human and rat cdc2 genes is present in the basal promoter region from positions -183 to -122, which contains the E box, SpI, and E2F motifs. The expression of 5' sequential deletion derivatives of the promoter fused to luciferase cDNA in rat 3Y1 cells revealed the presence of the enhancer element. The presumed enhancer region was further analyzed by the introduction of base substitutions and by the formation of DNA-protein complexes with cell extracts prepared at various times during the G1-to-S-phase progression. These analyses revealed that the enhancer sequence, AAGTTACAAATA, located from -276 to -265, confers strong inducibility on the basal promoter at the G1/S boundary. The base substitutions introduced into the motifs of transcription factors indicated that the E2F motif is essential for the enhancer-dependent activation of the cdc2 promoter at the G1/S boundary. Electrophoretic mobility shift assays and DNase I footprinting showed that a factor which interacts with the enhancer element is induced late in G1 phase.

Animals↗
PubMed1993

Immunohistochemical localization of cytokeratins in normal eccrine glands, with monoclonal antibodies in routinely processed, formalin-fixed, paraffin-embedded sections.

BACKGROUND: Immunohistochemical detection in paraffin sections would be of value in the retrospective analysis of formalin-fixed, paraffin-embedded tissues. OBJECTIVE AND METHODS: In this study with several monoclonal antibodies directed against fixation-resistant keratin antigens, we performed immunohistochemical staining on routine paraffin-embedded sections to localize specific keratins in the eccrine sweat glands and to determine the tissue distribution of various keratins. RESULTS: We clarified the localization of specific keratins in different segments of normal eccrine glands. Immunohistochemical localization of individual cytokeratins showed different patterns in secretory and ductal portions, although cytokeratins were expressed in all segments of normal sweat glands. Different immunoreactivities were noted in the luminal and basal cells of eccrine ducts. There were also some differences in immunophenotype between the acrosyringium and the dermal ducts. CONCLUSION: These data provide information for the determination of the histogenesis and differentiation of skin tumors with eccrine differentiation.

Antibodies, Monoclonal↗
PubMed1993

Immunohistochemical analysis of keratin distribution in eccrine poroma.

Although eccrine poroma has been thought of as a neoplasm of the intradermal eccrine duct, this interpretation has not been entirely confirmed. In this study, twenty-five cases of eccrine poroma were retrieved and analyzed by immunohistochemical techniques, using various kinds of monoclonal antikeratin antibodies. Comparative immunohistochemical observations of eccrine poroma and normal eccrine glands revealed that the poroma cells expressed immunophenotypes similar to those of the basal cells of dermal eccrine ducts. Sweat-ductlike structures showed similar staining patterns to those observed in the inner cells of dermal eccrine ducts. Some cystic spaces were similar to those observed in the secretory cells of eccrine glands. Eccrine poroma is, therefore, speculated to originate via the proliferation and expansion of the basal cells of eccrine ducts, although it is very difficult to prove the histogenesis. Some tumor cells may differentiate toward inner cells of the eccrine ducts, forming ductal lumina, whereas other tumor cells differentiate toward eccrine secretory regions, forming some cystic spaces.

Adenoma, Sweat Gland↗
PubMed1991

Abnormal distribution of epidermal protein antigens in psoriatic epidermis.

The immunohistochemical distribution of the epidermal proteins filaggrin, involucrin, and cytokeratins is characteristic in normal epidermis. This distribution may change as a result of malignant transformation or abnormal differentiation. The present study was conducted to determine the patterns of reactivity of psoriatic epidermis to antibodies against various epidermal proteins and to clarify abnormal differentiation or maturation of the keratinocytes in psoriatic epidermis. Anti-human filaggrin, anti-human involucrin, and twelve kinds of anti-cytokeratin antibodies were used in this study. Cryostat or paraffin-embedded sections were stained with these antibodies by the avidin-biotin peroxidase technique. The epidermis of the noninvolved skin of patients with psoriasis vulgaris showed the distribution seen in normal skin. However, involved psoriatic skin revealed little or no reaction in the stratum corneum or in the granular layer with the anti-filaggrin antibody. Cells positively staining with anti-involucrin antibody paradoxically appeared in the lower cell layers of involved psoriatic epidermis. An anti-keratin antibody, AE1, stained suprabasal cells in involved psoriatic epidermis, although this antibody selectively stained epidermal basal cells in normal skin. The other anti-keratin antibodies, especially KL1, PKK1, and a polyclonal anti-keratin antibody, were less reactive with involved psoriatic skin than with normal skin. These observations suggest that the maturation pathway of keratinocytes in active psoriatic lesions differs qualitatively from that in normal epidermis.

Adolescent↗
PubMed1991

Monoclonal antibody OKB19, reactive with a B-lymphoid differentiation antigen (CD19), binding to basal layer keratinocytes of normal human skin.

Monoclonal antibody (moAB) OKB19 reacts with CD19 antigen, which is the broadest lineage-specific surface marker on B-lymphocytes. In frozen tissue sections, using an immunohistochemical technique, the OKB19-positive cells in the basal layer were sharply demarcated from the negative suprabasal layers. In normal hair follicles, the OKB19 reactivity was also confined to one layer of the dermal side of the outer root sheath. However, this reactivity gradually disappeared in the lower areas. The inner surface of the lumina in the eccrine duct was weakly stained with OKB19. The basal keratinocytes were also stained with OKB19 in the lesional epidermis of the various dermatoses examined in this study, when the basal keratinocytes remained unaffected. Even in the hyperproliferative state of psoriasis, the OKB19 reactivity was confined to the basal layer. Several kinds of tumor cells derived from the skin were not stained with OKB19. No labeling was seen even in the basaloid cells of basal cell carcinoma, which are morphologically similar to basal keratinocytes. B4 and Leu-12, other monoclonal antibodies reacting with CD19, did not recognize any keratinocytes in the normal human skin. MoAB OKB19, therefore, reacts with an antigen present on basal keratinocytes and provides a probe for the isolation of the basal keratinocyte subpopulation. Thus, this antibody should be useful in studies of not only B-lymphocyte differentiation, but also normal and aberrant differentiation of the epidermal keratinocytes.

Antibodies, Monoclonal↗
PubMed1990

Datura stramonium agglutinin-reactive alpha-fetoprotein isoforms in hepatocellular carcinoma and other tumors.

By means of Datura stramonium agglutinin (DSA) affinity electrophoresis, human alpha-fetoprotein (AFP) was resolved into five bands, AFP-D1, D2, D3, D4 and D5, in order of decreasing mobility. AFP-D1, which had no affinity for DSA, comprised more than 84% of the intensity of total AFP bands. The percentage of AFP-D2 increased marginally in hepatitis and liver cirrhosis with or without hepatocellular carcinoma. AFP-D3 increased characteristically in hepatocellular carcinoma and AFP-D4, which had the highest affinity for DSA, increased up to 12% in other tumors, mostly of gastrointestinal origin. AFP-D5 showed no consistent changes among the benign and malignant diseases. The assay of AFP-D3 and D4 proved useful as a highly specific marker of hepatocellular carcinoma and other tumors, respectively.

Carcinoma, Hepatocellular↗
PubMed1990

[Drug eruption due to iohexol (Omnipaque)].

Disseminated maculopapular eruption developed 5 to 6 days after the administration of Iohexol (Omnipaque) for the drip infusion pyelography in three cases. The skin tests clearly demonstrated that Iohexol was the causative factor, and other Iodinated contrast mediums and Trometamol which contained in Omnipaque as stabilizing agent were negative skin tests.

Aged↗
PubMed1989

Two-dimensional lectin affinity electrophoresis of alpha-fetoprotein: characterization of erythroagglutinating phytohemagglutinin-dependent microheterogeneity forms.

By means of two-dimensional lectin affinity electrophoresis of human alpha-fetoprotein (AFP) from different sources, AFP bands separated with erythroagglutinating phytohemagglutinin (E-PHA) were further characterized with other lectins of known oligosaccharide specificities. The results with a cord serum AFP revealed that not only AFP-P2 (E-PHA-nonreactive) but also AFP-P4 and P5 (E-PHA-reactive) had affinities for Concanavalin A (Con A) and Allomyrina dichotoma lectin (allo A), indicating that the cord serum AFP has nonbisected biantennary complex-type oligosaccharides with the terminal galactose on Man alpha 1----6 residue sialylated at the C-6, but not C-3, position. On the other hand, the results with a hepatoblastoma (HUH-6 C1-5 cell line) AFP showed that not only AFP-P5 but also AFP-P1 (E-PHA-nonreactive) and P3 (E-PHA-less reactive) had Con A-nonreactive AFP and that AFP-P1 had AFP-A1 (allo A-nonreactive) and AFP-A2 (allo A-less reactive), and AFP-P3 and P4 had AFP-A1s (allo A-nonreactive), as main components, in addition to the spots of cord serum AFP. Most of the E-PHA-dependent bands of AFP were further subdivided with Lens culinaris agglutinin (LCA-A) into LCA-A-reactive, weakly reactive and nonreactive spots. Similar results were obtained with AFP preparations from hepatocellular carcinomas and other malignancies, indicating that the bisected bi-(or tri- and tetra-) antennary sugar chains with the exposed terminal galactose of the Man alpha 1----6 arm as well as those with the C-3 sialylated galactose residues could be expressed in AFP upon malignant transformation.(ABSTRACT TRUNCATED AT 250 WORDS)

Concanavalin A↗
PubMed1989

Lectin reactivity of alpha-fetoprotein in a case of renal cell carcinoma.

The increased serum level of alpha-fetoprotein (AFP) in a case of renal cell carcinoma, a rare condition of AFP production by mesoderm-derived cells, was evaluated for its lectin reactivity by affinity electrophoresis, followed by the antibody-affinity transfer to nitrocellulose membranes for visualization of separated AFP bands. The AFP of this case was characterized by relative increases of concanavalin A-nonreactive AFP-C1 (60.4%), erythroagglutinating phytohemagglutinin-reactive AFP-P4 (37.8%) and AFP-P5 (46.3%) and Allomyrina dichotoma lectin-nonreactive AFP-A1s (66.7%), and by the total absence of lentil lectin-reactive components, AFP-L2 and AFP-L3. Thus, the lectin-reactive pattern of AFP markedly deviated not only from that of cord serum, but also from those of other malignancies and of fetal kidney cells in culture.

Carcinoma, Renal Cell↗
PubMed1986

A tetrazolium method for staining peroxidase labels in blotting assays.

A sensitive staining method of horseradish peroxidase-labeled immunoglobulins on nitrocellulose membrane was established by employing a reaction chain leading to formazan formation with phenol as a substrate of peroxidase and NADH as a hydrogen donor to reduce nitro blue tetrazolium. Higher concentrations of NADH relative to phenol were necessary to increase the intensity of staining and to ensure a wide dose-response range of color production with respect to the applied enzyme activities. By an optimized tetrazolium method in combination with antibody-affinity blotting, as low as 4 ng/ml alpha-fetoprotein was detected and 3-4-fold greater color intensities in a working assay range as compared with those of existing methods were obtained. The present technique of peroxidase staining may prove to have a wide application for the enzyme immunoassay using blotting modalities.

Immunoenzyme Techniques↗
PubMed1986

Allomyrina dichotoma lectin-nonreactive alpha-fetoprotein in hepatocellular carcinoma and other tumors: comparison with Ricinus communis agglutinin-I.

Allomyrina dichotoma lectin (allo A) with a specificity to beta-D-galactose was used to fractionate human alpha-fetoprotein (AFP) by affinity electrophoresis. AFP from cord sera and serum of a patient with fulminant hepatitis showed single bands with a high affinity for allo A. Some patients with hepatocellular carcinoma and patients with gastric cancer and yolk sac tumor had two additional AFP bands, one weakly reactive and the other nonreactive with allo A. Patterns of AFP bands obtained with Ricinus communis agglutinin-I (RCA-I) and erythroagglutinating phytohemagglutinin from Phaseolus vulgaris were entirely different from those obtained with allo A. Of the two common bands reactive with RCA-I, the weakly reactive one was relatively intense in some malignant patients and the strongly reactive one was detected in patients with extrahepatic tumors. Thus, affinity electrophoresis with those lectins provides a potentially useful adjunct for the discrimination between benign and malignant conditions with increased serum levels of AFP.

Carcinoma, Hepatocellular↗
PubMed1986

[Properties of ATP-dependent H+-transport in rat brain synaptosomes].

Properties of the ATP-dependent H+-transport system in rat brain synaptosomes were examined using the acridine orange fluorescence quenching method. ATP-dependent H+-accumulation assessed by the quenching of acridine orange fluorescence was observed with the synaptosomes treated with hypotonic solution (hypotonic shock-synaptosomes), but not with the intact synaptosomes. With hypotonic shock-synaptosomes, H+-transport was activated in the presence of Cl- or Br-. However, this transport activity was markedly reduced in the presence of Mes-, NO3-, I- or SCN-. On the other hand, H+-transport activity was less effective with cations other than K+ in the following decreasing order of potency: K+ greater than Cs+ greater than Na+ greater than Li+. The H+-transport activity was inhibited by 0.3 mM ethacrynic acid, 10 microM 4-acetamide-4'-isothiocyanostilbene-2,2'-disulfonic acid or 1 mM 4-aminopyridine to 39.2%, 36.3%, or 33.1% of the control, respectively, but was not inhibited by 1 mM ouabain, 500 microM vanadate, 10 microM picrotoxin and 100 microM gamma-aminobutyric acid. These results suggest that the ATP binding site of the synaptosomal ATP-dependent H+-transport system exists on the internal surface of synaptosomal plasma membranes and that the H+-transport system is stimulated by the presence of Cl- or Br- and by K+ movement through the K+ channel.

Adenosine Triphosphate↗