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Biomedical subjects

Y Takasaki

Publications and source records attributed to Y Takasaki.

At least 19 recordsLinked to original sources
PubMed1992

Cell proliferation in childhood acute leukemia. Comparison of Ki-67 and proliferating cell nuclear antigen immunocytochemical and DNA flow cytometric analysis.

The proliferative activity of bone marrow leukemia cells was determined by DNA flow cytometric (FCM) analysis and labeling index (LI) of Ki-67 monoclonal antibodies and proliferating cell nuclear antigen (PCNA) autoantibodies in 73 children with acute leukemia. LI of Ki-67 varied greatly from patient to patient (range, 0.4% to 42.2%; mean, 18.8%) and differed significantly between acute lymphoblastic leukemia (ALL) and acute nonlymphoblastic leukemia (ANLL). In ALL, the Ki-67 LI showed a positive correlation with the S-phase fraction (SPF) determined by DNA FCM analysis, whereas, in ANLL, there was a discrepancy between the Ki-67 LI and SPF. In contrast, LI of PCNA varied less among the patients (range, 57.2% to 100%; mean, 90.3%), and the value was always higher than that of the Ki-67 LI in individual patients. A significant relationship between PCNA LI and the percentage of blast cells was found in peripheral blood leukocytes from patients with leukemia. These results suggest that the Ki-67 LI reflects differences in the proliferative activity depending on the subtype of the disease and that the PCNA LI is useful as a marker of proliferating cells.

Blast Crisis↗
PubMed1992

Detection and quantification of anti-Ki antibodies by enzyme-linked immunosorbent assay using recombinant Ki antigen.

OBJECTIVE: To establish an enzyme-linked immunosorbent assay (ELISA) for detecting anti-Ki antibody, using a bovine recombinant Ki antigen, and studying its specificity. METHODS: Sera from 220 patients with various connective tissue diseases were screened, and a prospective study of fluctuations in anti-Ki antibody and clinical course of a woman with systemic lupus erythematosus (SLE) was analyzed, by ELISA: RESULTS: Anti-Ki antibodies were present in 18.9% of patients with SLE. The titer of anti-Ki antibody in the woman with SLE rose before the onset of pericarditis and pleuritis in this longitudinal study. CONCLUSION: ELISA using a recombinant Ki antigen is useful for the diagnosis of SLE, and it might be useful in estimating disease activity in patients with SLE.

Animals↗
PubMed1992

Proliferating cell nuclear antigen (PCNA/cyclin) in plant proliferating cells: immunohistochemical and quantitative analysis using autoantibody and murine monoclonal antibodies to PCNA.

Proliferating-cell nuclear antigen (PCNA), also known as cyclin, is synthesized in proliferative cells and recently was identified as DNA polymerase-delta auxiliary protein. In this paper, the association of PCNA to the proliferative cells of plants was analysed using both autoantibodies to PCNA obtained from a patient with systemic lupus erythematosus (SLE) and murine monoclonal antibodies. By immunohistochemical analysis, nuclei of cells around the growing point in soybean root tips reacted strongly with autoantibodies to PCNA in the serum from a patient with SLE. The plant PCNA in root tip cells was purified by ammonium sulfate fractionation, DEAE chromatography, and affinity chromatography. The partially purified plant PCNA was tested by immunoblotting and a 34 kD polypeptide reacted with both the human anti-PCNA autoantibody and a mouse monoclonal antibody against human PCNA (TOB 7). In addition, the purified plant PCNA reacted with both antibodies in enzyme-linked immunosorbent assay (ELISA). The binding of anti-PCNA serum to the animal PCNA was blocked by the plant PCNA in this ELISA. The association of PCNA with growing cells in plants was further confirmed by quantitative sandwich type ELISA using two murine monoclonal antibodies to PCNA, TOB7 and TO17. Those results suggested that PCNA in both plant and animal cells had the same immunological and biochemical characteristics and the plant PCNA might play an important role in cell growth, existing as it does in proliferating plant cells. The concentration of PCNA in soybean germ extract before germination was less than 5 ng ml-1 (protein concentration, 6.8 mg ml-1), but that of the root tip stem including the growing point increased to 887 ng ml-1 (protein concentration 3.8 mg ml-1) in the second day after germination.

Animals↗
PubMed1992

Induction of proliferating cell nuclear antigen (PCNA) complex formation in quiescent fibroblasts from a xeroderma pigmentosum patient.

Accumulated evidence indicates that proliferating cell nuclear antigen (PCNA) is an auxiliary protein of DNA polymerase delta and forms tight association with DNA replication sites during DNA replication or DNA repair synthesis. In this study, such PCNA complex formation was investigated by the indirect immunofluorescence method, using both normal human fibroblasts and those derived from a xeroderma pigmentosum group A (XP-A) patient. XP-A fibroblasts in both proliferating and quiescent states did not show any differences from normal fibroblasts in the properties of PCNA-staining in the untreated conditions. The PCNA complex formation was induced in quiescent normal fibroblasts by both ultraviolet light (UV)- and X-irradiation, whereas in XP-A fibroblasts it was induced by X-irradiation, but not by UV-irradiation. However, PCNA complex was induced in quiescent XP-A fibroblasts by UV-irradiation when the cells had previously incorporated 5-bromodeoxyuridine (BrdU). These observations indicate a close correlation of PCNA complex formation and unscheduled DNA synthesis (UDS). Thus, it was concluded that PCNA complex formation was commonly induced in at least three conditions to produce UDS in spite of different types of DNA damages and DNA repair mechanisms.

Bromodeoxyuridine↗
PubMed1992

Restoration of proliferating cell nuclear antigen (PCNA) complex formation in xeroderma pigmentosum group A cells following cis-diamminedichloroplatinum (II)-treatment by cell fusion with normal cells.

We examined the role of the factor deficient in xeroderma pigmentosum group A (XP-A) cells in the formation of proliferating cell nuclear antigen (PCNA) complex with DNA in the DNA repair process in human fibroblasts following cis-diamminedichloroplatinum (CDDP)-treatment. Immunofluorescence staining after methanol fixation was used to detect the PCNA complex formation. When quiescent normal cells were PCNA-stained at 3 h after 100 microM CDDP treatment for 1 h, almost all nuclei of the cells showed a punctuated staining pattern. On the other hand, nuclei of XP-A cells were not stained. These results were the same with the findings following 10J/m2 of ultraviolet light (UV)-irradiation. The quantitative analysis of the PCNA immunofluorescence intensity of normal cells revealed that the mean intensity was increased by 4.8 times by the CDDP-treatment and 6.1 times by the UV-irradiation, compared with that of untreated cells. The intensities among nuclei ranged widely in both treatments. In contrast, the mean intensity was not increased in XP-A cells by the same treatments. However, when XP-A cells were fused with normal cells with polyethylene glycol (PEG) treatment, the nuclei of the XP-A cells showed positive PCNA-staining following CDDP-treatment or UV-irradiation in almost all cases. These results suggest that the PCNA complex formation may play a role in the DNA repair process after the step where the factor deficient in XP-A cells is involved following CDDP-treatment as well as following UV-irradiation.

Cell Division↗
PubMed1992

Proliferative activity of cutaneous melanocytic neoplasms defined by a proliferating cell nuclear antigen labelling index.

To evaluate the proliferative activity of benign, borderline and malignant cutaneous melanocytic neoplasms, 30 cases of malignant melanoma (MM) and 41 cases of naevi were studied by immunostaining using a monoclonal antibody against proliferating cell nuclear antigen (PCNA). PCNA is a nuclear antigen expressed in the late G1 and S phase and serves as a marker of proliferating cells. Invasive MM and MM in situ showed much higher PCNA positivity rates than melanocytic naevi (invasive MM, 18.0%; MM in situ, 11.3%; ordinary melanocytic naevi, 2.6%). The PCNA positivity rate did not increase significantly with the thickness of MM. Among ordinary melanocytic naevi, junctional naevi had a higher PCNA positivity rate than compound or intradermal naevi. Mean PCNA positivity rates for Spitz's naevi and sporadic dysplastic naevi were within the range for ordinary melanocytic naevi, indicating the benign nature of both types of naevus. Contrary to some previous studies, MM in situ showed high proliferative activity, indicating that cells of MM in situ are actively proliferating. This study clearly demonstrates that MM and various types of naevi can be separated according to differences in proliferative activity defined by the PCNA labeling index.

Antibodies, Monoclonal↗
PubMed1992

A case of Raynaud's disease with uterine cancer producing interleukin-6.

A case of cervical cancer of the uterine producing interleukin-6(IL-6) in a patient who suffered from Raynaud's phenomenon is described. Her serum contained anti SS-A antibody. The cancer was removed surgically. High level of IL-6 activity was detected in the culture supernatant of the resected cancer cells. After operation, Raynaud's phenomenon had improved and anti SS-A antibody had disappeared. This case shows us that IL-6 produced by malignant tumour might induce autoimmune connective tissue disease-like symptoms.

Aged↗
PubMed1992

Two types of proliferating cell nuclear antigen (PCNA) complex formation in quiescent normal and xeroderma pigmentosum group A fibroblasts following ultraviolet light (uv) irradiation.

We examined the relationship between the formation of proliferating cell nuclear antigen (PCNA) complex with DNA and nucleotide excision repair in human fibroblasts following ultraviolet light (uv) irradiation. PCNA complex formation was detected by the immunofluorescence method after methanol fixation and nucleotide excision repair activity was detected as the unscheduled DNA synthesis (UDS) by autoradiography labeled with [3H]thymidine. Quiescent normal cells showed a strong punctuated pattern of PCNA staining 5 min to 3 h and UDS 3 h after 10 J/m2 of uv irradiation, but they no longer showed PCNA staining and UDS 24 h after irradiation. In contrast, xeroderma pigmentosum group A (XP-A) cells, which lack UDS activity, did not show PCNA staining up to 30 min after irradiation; however, unexpectedly, they were stained 3 h and even 24 h after irradiation with their staining pattern being different from that in normal cells. Namely, the fluorescence spots in XP-A cells were larger in size and much smaller in number than those in normal cells. When XP-A cells were fused with normal cells with polyethylene glycol treatment, nuclei of XP-A cells showed a PCNA staining pattern similar to that of normal cells at 30 min, which was no longer detected 24 h after irradiation. These results suggest that there exist two types of PCNA complex formation, nucleotide excision repair-related and -unrelated, in human fibroblasts following uv irradiation.

Cell Fusion↗
PubMed1992

Distribution patterns and frequency of proliferating cells in cutaneous keratinocytic neoplasms. Immunohistochemical study with a monoclonal antibody (TOB7) used against proliferating cell nuclear antigen.

BACKGROUND: Almost all markers for proliferating cells need freshly frozen tissues for evaluation; therefore retrospective study is impossible. OBJECTIVE: In the present study, a murine monoclonal antibody (TOB7) against the proliferating cell nuclear antigen (PCNA) was used for the analysis of cell kinetics of cutaneous keratinocytic neoplasms. The antibody is applicable to formalin-fixed, paraffin-embedded tissues. METHODS: The frequency of PCNA-positive cells and their distribution patterns were immunohistochemically investigated in various cutaneous keratinocytic neoplasms. RESULTS: Squamous cell carcinoma and Bowen's disease showed significantly increased numbers of PCNA-positive cells when compared with other keratinocytic neoplasms. A characteristic marginal or random distribution pattern of PCNA-positive cells was observed in the lesions of each disease category. CONCLUSION: Important information on the growth dynamics of keratinocytic neoplasms was obtained in this retrospective immunohistochemical study.

Antibodies, Monoclonal↗
PubMed1992

Studies on chimeric fusion proteins of human aldolase isozymes A and B.

Several kinds of fusion proteins between human aldolases A and B were prepared by recombinant DNA technology and their enzymic properties were examined. AB chimeras, which have aldolase A at the N-terminal region and aldolase B at the C-terminal region, were scarcely obtained, while BA chimeras were abundant (Kitajima et al., (1990), J. Biol. Chem., 265, 17493-17498). All the BAB chimeras, aldolase A fragments inserted in aldolase B, showed activity assignable to aldolase B type, which imply an essential role of Tyr residue at the C-terminus of aldolase A in the binding of fructose-1,6-bisphosphate (Fru-1,6-P2). BAB chimeras also showed reactivity to effectors such as fructose-2,6-bisphosphate (Fru-2,6-P2) and pyridoxal 5-phosphate (PLP), in a similar manner to aldolase B. BAB108 has a similarity to the BA108 chimera, but acts differently from other BAB chimeras, suggesting that its structure around active site looks like that of aldolase A.

Escherichia coli↗
PubMed1992

[A case of mediastinal teratoma--differentiation from lung abscess and bronchogenic carcinoma].

A 38-year-old man was admitted with persistent productive cough and right anterior chest pain. Chest X-ray showed two large masses connected with each other, one in the right lung field and the other in the anterior mediastinum. A tentative diagnosis of either lung abscess or bronchogenic carcinoma was initially made, because of elevated serum tumor markers (SLX and SCC) and persisting refractory inflammatory sings. However, open chest drainage revealed a few fine hairs and atheromatous materials within the masses, and the diagnosis of teratoma was made. We removed these masses, and investigated the reason for the elevation of tumor markers. Staining with SLX monoclonal antibody demonstrated that the pancreatic tissue in the masses contained SLX. Although this is the first reported case of teratoma producing tumor marker (SLX), it is highly possible that tumor markers may be elevated in the majority of patients with teratoma because of the genesis of this tumor.

Adult↗
PubMed1992

Cell-cycle-associated expressions of proliferating cell nuclear antigen and Ki-67 reactive antigen of bone marrow blast cells in childhood acute leukemia.

To investigate the growth characteristics of human leukemia cells, the expression of proliferation-associated nuclear antigens was examined in relation to cell cycle phases in marrow blast cells obtained from 37 untreated children with acute leukemia. Ki-67 monoclonal antibody reactive antigen and proliferating cell nuclear antigen (PCNA) were measured by the simultaneous flow cytometric analysis of DNA and nuclear antigens. The percentage of PCNA-positive cells was always higher than that of Ki-67-positive cells in individual patients. The level of PCNA was greatly increased in G1 or early S phase, but was generally stable in S and G2 phases. Accordingly, most of the cells in the proliferative compartments (greater than 2C DNA) showed a high expression of PCNA. In contrast, expression of Ki-67 antigen varied greatly from patient to patient, and differed significantly in different subtypes of the disease. The level of Ki-67 antigen increased with the cell cycle progression, showing maximum expression in late S and G2 phases. However, in most of the patients, a distinct population of Ki-67-negative cells was found not only in G1 phase, but also in the proliferative compartments. These results appear to reflect differences in the proliferative activity of bone marrow blast cells in childhood acute leukemia.

Cell Cycle↗
PubMed1992

Reversible G1 arrest induced by dimethyl sulfoxide in human lymphoid cell lines: kinetics of the arrest and expression of the cell cycle marker proliferating cell nuclear antigen in Raji cells.

In order to elucidate further the mechanism of reversible cell cycle arrest induced by treatment of Raji cells with 1.5% dimethyl sulfoxide (DMSO), we have performed a detailed analysis of the kinetics of arrest and of reentry into the cell cycle after removal of DMSO and have correlated cell cycle progression with expression of proliferating cell nuclear antigen (PCNA). No significant effect of DMSO on cell cycle patterns, assessed by flow cytometric analysis of bromodeoxyuridine-prelabeled cells, was seen for the first 19 h of treatment. A clear reduction of entry into S phase was detected by about 25 h of treatment; essentially all cells were arrested with a G1 content of DNA after 96 h of treatment. When DMSO-arrested cells were released from the block, entry into S phase began at 12 h after release and continued in a fairly asynchronous manner for a further 12-14 h. In arrested cells, the content of PCNA was reduced to about 25% of the amount present in logarithmically growing G1 phase cells. Six h after release from DMSO, PCNA RNA transcripts were first detected by Northern blotting. The increase of PCNA protein, detected by Western blotting, was seen by 9 h after release. The kinetics of entry into the cell cycle and restoration of PCNA protein are similar to that seen in serum stimulation of quiescent cells. These results suggest that DMSO reversibly arrests proliferation of Raji cells at G0 or at an early point in G1 phase and that progression through late G1 phase and entry into S phase are correlated with synthesis of the PCNA gene product.

Antigens, Neoplasm↗
PubMed1992

[Endoscopic analysis of gastric mucosal lesions in patients with adult T-cell leukemia during chemotherapy].

Gastric mucosal lesions in 13 patients with adult T-cell leukemia (ATL) were endoscopically studied at least at 2 occasions during chemotherapy for these patients. X-ray examinations by using barium meal showed deformities in 10 patients and abnormal mucosal pattern in 11 out of 13 patients with ATL. The endoscopic examinations revealed gastric ulcers in 5 patients, erosion in 8, diffuse bleeding in 2, tumorous mucosal folds in one, and submucosal tumor in one patient. In 9 out of 12 ATL patients, pathological study revealed that ATL cells had invaded the mucosal area of the stomach. The ulcers and erosions were improved by chemotherapy in 3 out of 5 and 5 out of 8 patients, respectively, whereas the erosion was not reduced in 2 and even aggravated in one patient. Interestingly, the gastric lesions formed by ATL cell invasion were improved by the administration of anticancer agents in 5 out of 9 patients. However, these lesions reappeared together with systemic lesions of ATL.

Adult↗
PubMed1991

Induction of immunoreactive proliferating cell nuclear antigen (PCNA) in goldfish retina following intravitreal injection with tunicamycin.

Effects of a photoreceptor-specific biotoxin, tunicamycin (TM), injected intravitreally into the goldfish eye at one side, were explored on electroretinograms (ERGs) and proliferating cell nuclear antigen-immunoreactive (PCNA-ir) nuclei, representing the mitotic activity of rod precursors, in the retina at both sides. The eye-cup preparations were made for ERG recording, and the retinas were isolated and processed as cryosections or wholemounts by a routine immunohistochemical method for visinin (cones), opsin (rods), tyrosine hydroxylase (dopaminergic cells) and proliferating cell nuclear antigen (PCNA), at various intervals after intravitreal injection with TM (1.0 micrograms/eye). On some thin sections, autoradiographic study was combined following intravitreal injection with [3H]thymidine (TdR, 0.1 microCi/eye). The dose of TM used heavily destroyed cones and rods only in the treated retinas 2-15 days after injection, the photoreceptors being renewed for further 15-20 days. Approximately in parallel, ERGs were largely impaired 2-10 days after TM injection and recovered for 10-20 days. However, intravitreal TM altered the distribution and density of PCNA-ir nuclei in both treated and untreated retinas. The density of PCNA-ir nuclei reduced at first (on days 1 and 2), and then clustered and rapidly increased on days 3-5 and maintained at high levels with diffuse distribution over the whole area, particularly in the treated retinas, up to 60 days after TM injection; the maximum peak of 3.7 and 20 times the initial level was seen on day 20 in the outer nuclear layer (ONL) and inner nuclear layer (INL), respectively. PCNA-ir nuclei were found to be abundant in the ONL even after the photoreceptors and ERGs had been restored in the treated retinas on day 20, suggesting a kind of overproduction of retinal cells. The autoradiographic study provided comparable results to those obtained with PCNA immunohistochemistry. The mechanism by which damage to the treated retina causes rod precursor cells to proliferate in the untreated retina remains unresolved.

Animals↗
PubMed1991

Induction of proliferating cell nuclear antigen (PCNA)-immunoreactive cells in goldfish retina following intravitreal injection with 6-hydroxydopamine.

1. The dopaminergic neurotoxin, 6-hydroxydopamine (6-OHDA), was injected intravitreally into the eyes of juvenile (5- to 6-cm) goldfish. 2. Proliferation of rod neuroblasts caused by 6-OHDA (2 micrograms in 2 microliters saline) was detected in retinal wholemounts by immunofluorescence for proliferating cell nuclear antigen (PCNA) 3, 7, 14, 20, or 30 days after injection. 3. The injected dose of 6-OHDA was sufficient to cause permanent loss of dopaminergic interplexiform and serotonergic amacrine cells in the injected eye but not in the contralateral control eye. 4. 6-OHDA increased the density (mm-2) of PCNA-ir cells in the outer nuclear layer (ONL) of the injected eye to 2.65 times the initial density 20-30 days after injection, and it increased the density of PCNA-ir cells in the ONL of the contralateral, untreated eye, equally but after a delay of less than or equal to 7 days with respect to the injected eye. 5. 6-OHDA also increased the density of PCNA-ir cells in the inner nuclear layer (INL) to greater than 20 times the initial density 7 days after injection, followed by a rapid decline almost to control levels by 14 days after injection. 6. The sequence of responses to 6-OHDA, with PCNA-ir cells first scattered in the ONL and then clustered in the INL, suggests that neuroblasts from the ONL migrate to the INL to compensate for toxin-induced cell loss. 7. Double staining for 5-bromodeoxyuridine (BrUdR; a thymidine analogue) and PCNA, carried out on 7 days after intravitreal injection with 6-OHDA, showed that 77% of all PCNA-ir cells in the outer nuclear layer had been in S phase during the previous 24 hr. 8. Immunoreactivity for PCNA was found to be a valid marker for rod neuroblasts which have entered S phase within 1-2 days before sampling and was shown to be especially convenient for investigating the distribution of proliferating cells in whole mounts. 9. In controls injected unilaterally with saline or saline plus 1% dimethyl sulfoxide (DMSO), the differences in densities of PCNA-ir rod precursor nuclei 2-30 days after injection vs. day 0 (uninjected) were statistically insignificant in both injected and uninjected eyes (Negishi et al., 1991). Therefore the local effect of injecting 6-OHDA was due to 6-OHDA itself, not to mechanical damage or nonspecific actions of foreign substances.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1991

Clinical significance of IgG subclasses of Anti-Sm and U1 ribonucleoprotein antibodies in patients with systemic lupus erythematosus and mixed connective tissue disease.

IgG subclasses of anti-Sm and anti-U1 ribonucleoprotein (U1 RNP) antibodies were determined using a new clone of the anti-IgG2 antibody (HG2-56F). Although the predominance of IgG1 coincided with previous reports, IgG2 anti-Sm and U1 RNP antibodies were detected in numerous patients. IgG3 anti-Sm antibody significantly correlates with joint involvement and a high titer of anti-DNA antibody. On the other hand, IgG4 anti-U1 RNP antibody significantly correlated with esophageal dilation and muscular involvement. These results may suggest that some IgG subclasses are related to a specific clinical feature or manifestation.

Autoantibodies↗